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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20046C3131993-07-28028 July 1993 LER 93-015-00:on 930630,HPCI Sys Declared Inoperable Due to Indicated Flow During Surveillance.Caused by Foreign Matl That Plugged Portion of Restricting Orifice.Restricting Orifice Removed,Cleaned & reinstalled.W/930728 Ltr ML20046B5241993-07-26026 July 1993 LER 93-007-01:on 930317,automatic Closing of RCIC Sys Turbine Steam Supply Isolation Valves Occurred Due to High Steam Flow Signal.Increased Frequency of Valve Testing from Monthly to weekly.W/930726 Ltr ML20045F8601993-06-30030 June 1993 LER 93-014-00:on 930531,automatic Scram Occurred,Resulting from Operation of Auxiliary Transformer Differential Relay During Power Ascension.Uat Phase B & C Differential Relays Left Interchanged as Investigative aid.W/930630 Ltr ML20045E2301993-06-25025 June 1993 LER 93-013-00:on 930530,RCIC Sys Declared Inoperable & 7 Day TS 3.5.D.2 LCO Entered Due to Speed Oscillations Which Occurred After Several Minutes of steady-state Operation. Caused by Actuator Failure.Actuator replaced.W/930625 Ltr ML20045E2251993-06-25025 June 1993 LER 93-012-00:on 930529,unplanned PCIS Group I Isolation Signal Occurred While Opening MSIV During Startup,Resulting in Automatic Closing of Related Valves.Caused by Licensed Operator Error.Group 1 Isolation reset.W/930625 Ltr ML20045D6941993-06-23023 June 1993 LER 93-011-00:on 930525,determined That Initial as-found Popping Pressures of Pilot Valves for Three Target Rock Main Steam Relief Valves Out of TS Tolerance.Caused by Setpoint Drift.Valves Reworked & Reassembled by Target Rock Corp ML20045D1861993-06-18018 June 1993 LER 93-010-00:on 930519,SUT Became de-energized During Planned Calibr of Turbine/Generator Relays Lockout Test While Shut Down.Caused by Personnel Error.Discussion Conducted W/Personnel Re Attention to detail.W/930618 Ltr ML20044H0441993-06-0202 June 1993 LER 93-009-00:on 930504,circuit Breaker Did Not Close During Planned Bus Transfer Due to Loose Control Circuit Wire.Lug Replaced & Reterminated on 930505 & Post Work Testing Completed W/Satisfactory results.W/930602 Ltr ML20024G7451991-04-24024 April 1991 LER 91-005-00:on 910325,diesel Generator Inoperable,Causing Loss of Ac Power to Train B Components of Safety Sys & Actuating Portions of Primary/Secondary Containment Sys. Caused by Voltage Regulator failure.W/910424 Ltr ML20029A6721991-02-25025 February 1991 LER 91-001-00:on 910125,automatic Primary Containment Isolation Control Sys Group 5 Actuation Occurred,Resulting in Closing of RCIC Turbine Steam Supply Isolation Valves. Caused by High Flow conditions.W/910225 Ltr ML20028G9731990-09-20020 September 1990 LER 89-036-01:on 891122,determined That HPCI Sys Inoperable Due to Inoperable Gland Seal Condenser Blower Motor.Caused by age-related Wear of Motor.Blower Motor Replaced & Blower Tested W/Satisfactory results.W/900920 Ltr ML20028G9121990-09-18018 September 1990 LER 89-037-01:on 891130,primary Containment/Traversing in-core Probe Ball Valve Discovered to Be Almost Full Open. Caused by Damage to Valve Stem Due to Manual Manipulation of Stem.Ball Valve & Solenoid Actuator replaced.W/900918 Ltr ML20043G3541990-06-12012 June 1990 LER 90-008-00:on 900513,automatic Scram Resulting from Load Rejection Occurred While at Full Power,Resulting in Trip of Generator Field Breakers.Caused by Fault on Offsite 345 Kv Transmission sys.Loss-of-field Relay replaced.W/900612 Ltr ML20043F8291990-06-0606 June 1990 LER 90-007-00:on 900507,discovered That Drywell to Suppression Chamber Vacuum Breaker Surveillance Not Performed Prior to Startup in 1988.Caused by Misunderstanding of requirements.W/900606 Ltr ML20042F5911990-04-30030 April 1990 LER 90-006-00:on 900330,determined That Position of Primary Containment Sys Isolation Valve Not Recorded Daily,Per Tech Specs.Review Performed to Determine If Other Problems Existed.Plant Shut Down & Review performed.W/900430 Ltr ML20012F5751990-04-0606 April 1990 LER 90-003-00:on 900311,automatic Actuation of Main Steam Sys Group 1 Portion of Primary Containment Isolation Control Sys Occurred.Caused by False High Reactor Vessel Water Level Signal.Procedure Developed Re backfill.W/900406 Ltr ML20012E9831990-03-30030 March 1990 LER 90-002-00:on 900228,determined That Max Fraction of Limiting Power Density Not Checked Daily During Reactor Power Operation,Per Tech Spec 4.1.B.On 900323,addl Tech Spec Issue Discovered.Tech Specs changed.W/900330 Ltr ML20012C4871990-03-12012 March 1990 LER 90-001-00:on 900209,24 H Limiting Condition for Operation Entered When Two RCS Instrumentation Excess Flow Check Valves Inappropriately Verified Operable During Testing.Cause Undetermined.Two Valves replaced.W/900312 Ltr ML20005G0981990-01-0808 January 1990 LER 89-038-00:on 891208,unplanned Automatic Reactor Protection Sys Scram Signal & Reactor Scram Occurred.Caused by False Low Reactor Vessel Water Level Signal.Local Level Indicators Satisfactorily calibr.W/900108 Ltr ML20005F8481990-01-0808 January 1990 LER 89-039-00:on 891209,automatic Actuation of RHR Sys Portion of Primary Containment Isolation Control Sys Occurred.Caused by Hydrodynamic Transient That Actuated Protective High Pressure switches.W/900108 Ltr ML20005E8551989-12-30030 December 1989 LER 89-037-00:on 891130,discovered That Traversing in-core Probe Ball Valve,Mfg by Consolidated Controls,Inc,Closed,In Violation of Tech Specs.Caused by Damage to Valve Stem.Ball Valve & Actuator replaced.W/891230 Ltr ML20011D1361989-12-11011 December 1989 LER 89-035-00:on 891111,inadvertent Actuation of Portion of Secondary Containment Sys During Surveillance Testing Occurred.Caused by Location of Radiation Isolation Control Sys Channel a Logic Relay.Procedure revised.W/891211 Ltr ML20005D7421989-12-0606 December 1989 LER 89-033-00:on 891106,automatic Actuation of Group 1 Portion of Primary Containment Isolation Control Sys (PCIS) Occurred.Caused by High Reactor Vessel Water Level.Manual Valve Closed & PCIS Logic Circuitry reset.W/891206 Ltr ML19351A4581989-12-0606 December 1989 LER 89-034-00:on 891108,determined That Reactor Pressure Exceeded 150 Psig on 891107 W/O Performing Surveillance Procedure 8.5.4.4, HPCI Valve Operability Test. Caused by Personnel Error.Procedure initiated.W/891206 Ltr ML19332D1421989-11-22022 November 1989 LER 89-031-00:on 891024,closing Times for Two in-series Primary Containment Isolation Valves Exceeded Acceptance Criteria During Shutdown Testing.Cause Undetermined.Closing Time Retested W/Satisfactory results.W/891122 Ltr ML19332D6231989-11-20020 November 1989 LER 89-032-00:on 891020,pneumatic Pressure Drop for Two of Four Automatic Depressurization Sys Accumulators Discovered Greater than Max Acceptable Value.Caused by Leakage from Seat of Supply Check Valves.Seat replaced.W/891120 Ltr ML19324C3181989-11-0909 November 1989 LER 88-002-01:on 880117,full Reactor Protection Sys Scram Trip Signal Occurred During Surveillance Test,Resulting in Incomplete Actuations.Caused by Procedure Inadequacy.Logic Relay Replaced & Procedure revised.W/891109 Ltr ML19324B1131989-10-21021 October 1989 LER 89-030-00:on 890926,control Room High Efficiency Air Filtration Sys Flowrate non-conservative Due to Procedure Error.Caused by Transcription Error.Procedure Revised & Test Reperformed Using Corrected procedure.W/891021 Ltr ML19325D4681989-10-16016 October 1989 LER 89-029-00:on 890914,locked High Radiation Area Door Found to Have Been Unsecured Contrary to Tech Spec 6.13.2. Caused by Failure to Adhere to Approved Procedures. Training on Access Requirements initiated.W/891016 Ltr ML19325D1861989-10-10010 October 1989 LER 89-028-00:on 890907,HPCI Sys Declared Inoperable Because Mechanical Overspeed Trip Occurred During Surveillance Test. Caused by Failure of Ramp Generator Signal Converter Module. Module Removed & Sent to Mfg for exam.W/891010 Ltr ML17277B8221984-07-20020 July 1984 LER 82-049/01X-1:on 821102,main Steam Line Safety Valve a Set W/Nitrogen at Steam Relief Setting.Caused by Personnel Error.Valve Removed & Replaced W/Properly Set Spare Valve. Procedure revised.W/840720 Ltr ML20024C3231983-06-24024 June 1983 Updated LER 82-038/03X-1:on 820817,RCIC Steam Line High Differential Pressure Alarm Received.Caused by Air in Sensing Lines to Pressure Switches.Cross Threaded Cap Found on in-line Snubber.Snubber replaced.W/830624 Ltr ML20024C2211983-06-24024 June 1983 Updated LER 80-053/03X-1:on 800814,0907 & 14,HPCI Turbine Exhaust Line Snubber 23-3-36 Determined Inoperable.Caused by Transient Hydrodynamic Shock During Startup & Shutdown. Snubbers upgraded.W/830624 Ltr ML20024B8451983-06-24024 June 1983 LER 83-031/03L-0:on 830528,HPCI Sys Made Inoperable to Repair Steam Leak on AO 2301-31.Caused by Leaking Stem Packing.Packing Replaced.Valve Tested Satisfactorily.Sys Returned to svc.W/830624 Ltr ML20024B8321983-06-24024 June 1983 LER 83-030/03L-0:on 830527,both HPCI Area Smoke Detection Sys Alarmed in Main Control Room.Caused by Valve A02301-31 Steam Leak Causing False Indications.Valve repaired.W/830624 Ltr ML20024C3101983-06-21021 June 1983 Updated LER 79-007/03X-1:on 790212,while Performing Test 8.7.4.3,valves AO-5033A,CV-5065-10,15,16 & 17 Failed to Give Proper Position Indication When Cycled & to Close within Specified Tolerance.Cause Not stated.W/830621 Ltr ML20024A8861983-06-16016 June 1983 LER 83-027/03L-0:on 830518,during Routine Insp,Folding Fire Door Found Inoperable.Caused by Operating Cable Becoming Detached from Pulley Due to Slack.Cable Reattached & Operating Mechanism adjusted.W/830616 Ltr ML20023D1691983-05-0909 May 1983 Updated LER 82-008/01X-1:on 820331,HPCI Injection Valve MO-2301-8 Failed to Open in Required Manner.Caused by Missing Wire Jumper Intended to Bypass Motor Operator Torque Switch.Jumper Installed & Valve Tested Satisfactorily ML20023D0671983-05-0909 May 1983 LER 83-021/03L-0:on 830411,during Surveillance Test 8.7.4.3, Primary Containment Isolation Valve AO-5033B Failed to Meet 10-s Closing Time Requirements.Caused by Lubricant Infiltrating Solenoid Valve Components.Components Replaced ML20023D0181983-05-0404 May 1983 LER 83-022/03L-0:on 830413,overload on Valve Motor 1301-17 Resulted in Loss of High Pressure Core Cooling Backup Capability.Caused by Oxidation in Motor End Bell & Motor Brushes,Due to Humidity Caused by Leaking Valve Packing ML20028G1591983-01-28028 January 1983 LER 83-002/01T-0:on 830116,flow Ref off-normal Alarm Received.Average Power Range Monitor Flux Scram Trip Settings Affected.Cause Under Investigation.Flow Inputs Monitored & Amplifier B Recalibr ML20028F4121983-01-17017 January 1983 LER 83-002/01X-0:on 830116,while Clearing off-normal Alarm for Flow Comparators,Average Power Range Monitor Flux Scram Trip Settings Found in Nonconservative Direction.Caused by Drifting Proportional Amplifiers.Settings Checked Daily ML20028B0421982-11-16016 November 1982 LER 82-049/01T-0:on 821102,main Steam Line Safety Valve a Set W/Nitrogen at Steam Relief Setting of 1240 Psig, Exceeding Tech Specs.Caused by Personnel Error.Set Valve Removed,Procedure Adherence Stressed & Procedure Revised ML20027C9801982-10-20020 October 1982 LER 82-039/03L-0:on 820920,timing Tests of Three Reactor Water Cleanup Isolation Valves 1201-2,-5 & -80 Not Completed within Allowed Time.Caused by Operational Constraints Requiring Testing at Reduced Power ML20027C9941982-10-20020 October 1982 LER 82-040/03L-0:on 820920,found Reactor Protection Sys Initiation Function of Turbine Stop Valve Completed 1 Day Late.Caused by Decision to Defer Test Due to MSIV D Line Isolation.Tracking Sys Implemented to Prevent Recurrences ML20052B9141982-04-23023 April 1982 LER 82-010/03L-0:on 820326,during Review of Testing Requirements,Surveillance Test 8.I.4 Standby Liquid Control Sys Found Not Verified.Caused by Breakdown in Multidiscipline Review of Results ML20052F2071982-04-14014 April 1982 Updated LER 81-060/03X-1:on 811020,determined Potential Exists to Reduce Number of Operable APRM & IRM Instrument Channels in Rod Block Trip Sys to Below Tech Spec Min ML20050A6321982-03-19019 March 1982 Updated LER 82-055/01T-1:on 810926,during Shutdown,Yarway Level Indicators Started Oscillating.Drywell Temp Was 240 F at 81-ft W/Elevation Coolant Temp 220 F.Caused by Ineffective Drywell Cooling.Ventilation Returned to Svc ML20050A4521982-03-19019 March 1982 LER 82-006/01T-0:on 820304,while Performing Maint Re SIL 352 on Pressure Adjustment Mechanism HPCI Stop Valve,Three Broken cap-screws Found.No Cause Determined.Screws Examined, Replaced & Sys Returned to Svc ML20050A4331982-03-19019 March 1982 Updated LER 81-062/01X-1:on 811116,Wyle Labs Informed Util That Two Target Rock Safety Relief Valves Had Not Passed Setpoint Tests.Caused by Setpoint Shift Due to Changes to Designed Differential Forces from Excessive Pilot Leakage 1993-07-28
[Table view] Category:RO)
MONTHYEARML20046C3131993-07-28028 July 1993 LER 93-015-00:on 930630,HPCI Sys Declared Inoperable Due to Indicated Flow During Surveillance.Caused by Foreign Matl That Plugged Portion of Restricting Orifice.Restricting Orifice Removed,Cleaned & reinstalled.W/930728 Ltr ML20046B5241993-07-26026 July 1993 LER 93-007-01:on 930317,automatic Closing of RCIC Sys Turbine Steam Supply Isolation Valves Occurred Due to High Steam Flow Signal.Increased Frequency of Valve Testing from Monthly to weekly.W/930726 Ltr ML20045F8601993-06-30030 June 1993 LER 93-014-00:on 930531,automatic Scram Occurred,Resulting from Operation of Auxiliary Transformer Differential Relay During Power Ascension.Uat Phase B & C Differential Relays Left Interchanged as Investigative aid.W/930630 Ltr ML20045E2301993-06-25025 June 1993 LER 93-013-00:on 930530,RCIC Sys Declared Inoperable & 7 Day TS 3.5.D.2 LCO Entered Due to Speed Oscillations Which Occurred After Several Minutes of steady-state Operation. Caused by Actuator Failure.Actuator replaced.W/930625 Ltr ML20045E2251993-06-25025 June 1993 LER 93-012-00:on 930529,unplanned PCIS Group I Isolation Signal Occurred While Opening MSIV During Startup,Resulting in Automatic Closing of Related Valves.Caused by Licensed Operator Error.Group 1 Isolation reset.W/930625 Ltr ML20045D6941993-06-23023 June 1993 LER 93-011-00:on 930525,determined That Initial as-found Popping Pressures of Pilot Valves for Three Target Rock Main Steam Relief Valves Out of TS Tolerance.Caused by Setpoint Drift.Valves Reworked & Reassembled by Target Rock Corp ML20045D1861993-06-18018 June 1993 LER 93-010-00:on 930519,SUT Became de-energized During Planned Calibr of Turbine/Generator Relays Lockout Test While Shut Down.Caused by Personnel Error.Discussion Conducted W/Personnel Re Attention to detail.W/930618 Ltr ML20044H0441993-06-0202 June 1993 LER 93-009-00:on 930504,circuit Breaker Did Not Close During Planned Bus Transfer Due to Loose Control Circuit Wire.Lug Replaced & Reterminated on 930505 & Post Work Testing Completed W/Satisfactory results.W/930602 Ltr ML20024G7451991-04-24024 April 1991 LER 91-005-00:on 910325,diesel Generator Inoperable,Causing Loss of Ac Power to Train B Components of Safety Sys & Actuating Portions of Primary/Secondary Containment Sys. Caused by Voltage Regulator failure.W/910424 Ltr ML20029A6721991-02-25025 February 1991 LER 91-001-00:on 910125,automatic Primary Containment Isolation Control Sys Group 5 Actuation Occurred,Resulting in Closing of RCIC Turbine Steam Supply Isolation Valves. Caused by High Flow conditions.W/910225 Ltr ML20028G9731990-09-20020 September 1990 LER 89-036-01:on 891122,determined That HPCI Sys Inoperable Due to Inoperable Gland Seal Condenser Blower Motor.Caused by age-related Wear of Motor.Blower Motor Replaced & Blower Tested W/Satisfactory results.W/900920 Ltr ML20028G9121990-09-18018 September 1990 LER 89-037-01:on 891130,primary Containment/Traversing in-core Probe Ball Valve Discovered to Be Almost Full Open. Caused by Damage to Valve Stem Due to Manual Manipulation of Stem.Ball Valve & Solenoid Actuator replaced.W/900918 Ltr ML20043G3541990-06-12012 June 1990 LER 90-008-00:on 900513,automatic Scram Resulting from Load Rejection Occurred While at Full Power,Resulting in Trip of Generator Field Breakers.Caused by Fault on Offsite 345 Kv Transmission sys.Loss-of-field Relay replaced.W/900612 Ltr ML20043F8291990-06-0606 June 1990 LER 90-007-00:on 900507,discovered That Drywell to Suppression Chamber Vacuum Breaker Surveillance Not Performed Prior to Startup in 1988.Caused by Misunderstanding of requirements.W/900606 Ltr ML20042F5911990-04-30030 April 1990 LER 90-006-00:on 900330,determined That Position of Primary Containment Sys Isolation Valve Not Recorded Daily,Per Tech Specs.Review Performed to Determine If Other Problems Existed.Plant Shut Down & Review performed.W/900430 Ltr ML20012F5751990-04-0606 April 1990 LER 90-003-00:on 900311,automatic Actuation of Main Steam Sys Group 1 Portion of Primary Containment Isolation Control Sys Occurred.Caused by False High Reactor Vessel Water Level Signal.Procedure Developed Re backfill.W/900406 Ltr ML20012E9831990-03-30030 March 1990 LER 90-002-00:on 900228,determined That Max Fraction of Limiting Power Density Not Checked Daily During Reactor Power Operation,Per Tech Spec 4.1.B.On 900323,addl Tech Spec Issue Discovered.Tech Specs changed.W/900330 Ltr ML20012C4871990-03-12012 March 1990 LER 90-001-00:on 900209,24 H Limiting Condition for Operation Entered When Two RCS Instrumentation Excess Flow Check Valves Inappropriately Verified Operable During Testing.Cause Undetermined.Two Valves replaced.W/900312 Ltr ML20005G0981990-01-0808 January 1990 LER 89-038-00:on 891208,unplanned Automatic Reactor Protection Sys Scram Signal & Reactor Scram Occurred.Caused by False Low Reactor Vessel Water Level Signal.Local Level Indicators Satisfactorily calibr.W/900108 Ltr ML20005F8481990-01-0808 January 1990 LER 89-039-00:on 891209,automatic Actuation of RHR Sys Portion of Primary Containment Isolation Control Sys Occurred.Caused by Hydrodynamic Transient That Actuated Protective High Pressure switches.W/900108 Ltr ML20005E8551989-12-30030 December 1989 LER 89-037-00:on 891130,discovered That Traversing in-core Probe Ball Valve,Mfg by Consolidated Controls,Inc,Closed,In Violation of Tech Specs.Caused by Damage to Valve Stem.Ball Valve & Actuator replaced.W/891230 Ltr ML20011D1361989-12-11011 December 1989 LER 89-035-00:on 891111,inadvertent Actuation of Portion of Secondary Containment Sys During Surveillance Testing Occurred.Caused by Location of Radiation Isolation Control Sys Channel a Logic Relay.Procedure revised.W/891211 Ltr ML20005D7421989-12-0606 December 1989 LER 89-033-00:on 891106,automatic Actuation of Group 1 Portion of Primary Containment Isolation Control Sys (PCIS) Occurred.Caused by High Reactor Vessel Water Level.Manual Valve Closed & PCIS Logic Circuitry reset.W/891206 Ltr ML19351A4581989-12-0606 December 1989 LER 89-034-00:on 891108,determined That Reactor Pressure Exceeded 150 Psig on 891107 W/O Performing Surveillance Procedure 8.5.4.4, HPCI Valve Operability Test. Caused by Personnel Error.Procedure initiated.W/891206 Ltr ML19332D1421989-11-22022 November 1989 LER 89-031-00:on 891024,closing Times for Two in-series Primary Containment Isolation Valves Exceeded Acceptance Criteria During Shutdown Testing.Cause Undetermined.Closing Time Retested W/Satisfactory results.W/891122 Ltr ML19332D6231989-11-20020 November 1989 LER 89-032-00:on 891020,pneumatic Pressure Drop for Two of Four Automatic Depressurization Sys Accumulators Discovered Greater than Max Acceptable Value.Caused by Leakage from Seat of Supply Check Valves.Seat replaced.W/891120 Ltr ML19324C3181989-11-0909 November 1989 LER 88-002-01:on 880117,full Reactor Protection Sys Scram Trip Signal Occurred During Surveillance Test,Resulting in Incomplete Actuations.Caused by Procedure Inadequacy.Logic Relay Replaced & Procedure revised.W/891109 Ltr ML19324B1131989-10-21021 October 1989 LER 89-030-00:on 890926,control Room High Efficiency Air Filtration Sys Flowrate non-conservative Due to Procedure Error.Caused by Transcription Error.Procedure Revised & Test Reperformed Using Corrected procedure.W/891021 Ltr ML19325D4681989-10-16016 October 1989 LER 89-029-00:on 890914,locked High Radiation Area Door Found to Have Been Unsecured Contrary to Tech Spec 6.13.2. Caused by Failure to Adhere to Approved Procedures. Training on Access Requirements initiated.W/891016 Ltr ML19325D1861989-10-10010 October 1989 LER 89-028-00:on 890907,HPCI Sys Declared Inoperable Because Mechanical Overspeed Trip Occurred During Surveillance Test. Caused by Failure of Ramp Generator Signal Converter Module. Module Removed & Sent to Mfg for exam.W/891010 Ltr ML17277B8221984-07-20020 July 1984 LER 82-049/01X-1:on 821102,main Steam Line Safety Valve a Set W/Nitrogen at Steam Relief Setting.Caused by Personnel Error.Valve Removed & Replaced W/Properly Set Spare Valve. Procedure revised.W/840720 Ltr ML20024C3231983-06-24024 June 1983 Updated LER 82-038/03X-1:on 820817,RCIC Steam Line High Differential Pressure Alarm Received.Caused by Air in Sensing Lines to Pressure Switches.Cross Threaded Cap Found on in-line Snubber.Snubber replaced.W/830624 Ltr ML20024C2211983-06-24024 June 1983 Updated LER 80-053/03X-1:on 800814,0907 & 14,HPCI Turbine Exhaust Line Snubber 23-3-36 Determined Inoperable.Caused by Transient Hydrodynamic Shock During Startup & Shutdown. Snubbers upgraded.W/830624 Ltr ML20024B8451983-06-24024 June 1983 LER 83-031/03L-0:on 830528,HPCI Sys Made Inoperable to Repair Steam Leak on AO 2301-31.Caused by Leaking Stem Packing.Packing Replaced.Valve Tested Satisfactorily.Sys Returned to svc.W/830624 Ltr ML20024B8321983-06-24024 June 1983 LER 83-030/03L-0:on 830527,both HPCI Area Smoke Detection Sys Alarmed in Main Control Room.Caused by Valve A02301-31 Steam Leak Causing False Indications.Valve repaired.W/830624 Ltr ML20024C3101983-06-21021 June 1983 Updated LER 79-007/03X-1:on 790212,while Performing Test 8.7.4.3,valves AO-5033A,CV-5065-10,15,16 & 17 Failed to Give Proper Position Indication When Cycled & to Close within Specified Tolerance.Cause Not stated.W/830621 Ltr ML20024A8861983-06-16016 June 1983 LER 83-027/03L-0:on 830518,during Routine Insp,Folding Fire Door Found Inoperable.Caused by Operating Cable Becoming Detached from Pulley Due to Slack.Cable Reattached & Operating Mechanism adjusted.W/830616 Ltr ML20023D1691983-05-0909 May 1983 Updated LER 82-008/01X-1:on 820331,HPCI Injection Valve MO-2301-8 Failed to Open in Required Manner.Caused by Missing Wire Jumper Intended to Bypass Motor Operator Torque Switch.Jumper Installed & Valve Tested Satisfactorily ML20023D0671983-05-0909 May 1983 LER 83-021/03L-0:on 830411,during Surveillance Test 8.7.4.3, Primary Containment Isolation Valve AO-5033B Failed to Meet 10-s Closing Time Requirements.Caused by Lubricant Infiltrating Solenoid Valve Components.Components Replaced ML20023D0181983-05-0404 May 1983 LER 83-022/03L-0:on 830413,overload on Valve Motor 1301-17 Resulted in Loss of High Pressure Core Cooling Backup Capability.Caused by Oxidation in Motor End Bell & Motor Brushes,Due to Humidity Caused by Leaking Valve Packing ML20028G1591983-01-28028 January 1983 LER 83-002/01T-0:on 830116,flow Ref off-normal Alarm Received.Average Power Range Monitor Flux Scram Trip Settings Affected.Cause Under Investigation.Flow Inputs Monitored & Amplifier B Recalibr ML20028F4121983-01-17017 January 1983 LER 83-002/01X-0:on 830116,while Clearing off-normal Alarm for Flow Comparators,Average Power Range Monitor Flux Scram Trip Settings Found in Nonconservative Direction.Caused by Drifting Proportional Amplifiers.Settings Checked Daily ML20028B0421982-11-16016 November 1982 LER 82-049/01T-0:on 821102,main Steam Line Safety Valve a Set W/Nitrogen at Steam Relief Setting of 1240 Psig, Exceeding Tech Specs.Caused by Personnel Error.Set Valve Removed,Procedure Adherence Stressed & Procedure Revised ML20027C9801982-10-20020 October 1982 LER 82-039/03L-0:on 820920,timing Tests of Three Reactor Water Cleanup Isolation Valves 1201-2,-5 & -80 Not Completed within Allowed Time.Caused by Operational Constraints Requiring Testing at Reduced Power ML20027C9941982-10-20020 October 1982 LER 82-040/03L-0:on 820920,found Reactor Protection Sys Initiation Function of Turbine Stop Valve Completed 1 Day Late.Caused by Decision to Defer Test Due to MSIV D Line Isolation.Tracking Sys Implemented to Prevent Recurrences ML20052B9141982-04-23023 April 1982 LER 82-010/03L-0:on 820326,during Review of Testing Requirements,Surveillance Test 8.I.4 Standby Liquid Control Sys Found Not Verified.Caused by Breakdown in Multidiscipline Review of Results ML20052F2071982-04-14014 April 1982 Updated LER 81-060/03X-1:on 811020,determined Potential Exists to Reduce Number of Operable APRM & IRM Instrument Channels in Rod Block Trip Sys to Below Tech Spec Min ML20050A6321982-03-19019 March 1982 Updated LER 82-055/01T-1:on 810926,during Shutdown,Yarway Level Indicators Started Oscillating.Drywell Temp Was 240 F at 81-ft W/Elevation Coolant Temp 220 F.Caused by Ineffective Drywell Cooling.Ventilation Returned to Svc ML20050A4521982-03-19019 March 1982 LER 82-006/01T-0:on 820304,while Performing Maint Re SIL 352 on Pressure Adjustment Mechanism HPCI Stop Valve,Three Broken cap-screws Found.No Cause Determined.Screws Examined, Replaced & Sys Returned to Svc ML20050A4331982-03-19019 March 1982 Updated LER 81-062/01X-1:on 811116,Wyle Labs Informed Util That Two Target Rock Safety Relief Valves Had Not Passed Setpoint Tests.Caused by Setpoint Shift Due to Changes to Designed Differential Forces from Excessive Pilot Leakage 1993-07-28
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217E3021999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Pilgrim Nuclear Station.With ML20212C2921999-09-16016 September 1999 SER Accepting Licensee Request for Relief from ASME Code Section XI Requirements as Endorsed by 10CFR50.55a for Containment Insp for Pilgrim Nuclear Power Station ML20216F3511999-09-0808 September 1999 ISI Summary Rept for Refuel Outage 12 at Pnps ML20216E6881999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Pilgrim Nuclear Power Station.With ML20210R3401999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Pilgrim Nuclear Power Station.With ML20209C4731999-07-0707 July 1999 Addendum to SE on Proposed Transfer of Operating License & Matls License from Boston Edison Co to Entergy Nuclear Generation Co ML20209H8251999-07-0101 July 1999 Provides Commission with Evaluation of & Recommendations for Improvement in Processes Used in Staff Review & Approval of Applications for Transfer of Operating Licenses of TMI-1 & Pilgrim Station ML20209E6191999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Pilgrim Nuclear Power Station.With ML20196H2451999-06-29029 June 1999 SER Denying Licensee Proposed Alternative in Relief Request PRR-13,rev 2.Staff Determined That Proposed Alternative Provides Insufficient Info to Determine Adequacy of Scope of Implementation ML20209A8901999-06-28028 June 1999 SER Accepting Licensee Proposed Alternative to Use Code Case N-573 for Remainder of 10-year Interval Pursuant to 10CFR50.55a(a)(3)(i) ML20209B9861999-06-23023 June 1999 Rev 13A to Pilgrim Nuclear Power Station COLR for Cycle 13 ML20217N9061999-06-21021 June 1999 Rept of Changes,Tests & Experiments for Period of 970422-990621 ML20195K3431999-06-15015 June 1999 Safety Evaluation Granting Licensee Request to Use Guidance of GL 90-05 to Repair Flaws in ASME Class 3 Salt Svc Water System Piping for Plant ML20195G8231999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Pnps.With ML20207E7471999-05-27027 May 1999 Safety Evaluation Granting Request Re Reduction of IGSCC Insp of Category D Welds Due to Implementation of HWC to License DPR-35 ML20206M1971999-05-11011 May 1999 SER Accepting Request for Approval to Repair Flaws in ASME Code Class 3 Salt Svc Water Piping at Plant ML20206J6611999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Pilgrim Nuclear Power Station.With ML20205L0221999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Pilgrim Nuclear Power Station.With ML20207J5471999-03-0909 March 1999 Training Simulator,1999 4-Yr Certification Rept ML20207F9401999-03-0101 March 1999 Long Term Program Semi-Annual Rept for Pilgrim Nuclear Power Station ML20207H5451999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for Pilgrim Nuclear Power Station.With ML20196E2151998-12-31031 December 1998 1998 Annual Rept for Boston Edison & Securities & Exchange Commission Form 10-K Rept.With ML20206Q2741998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for Pilgrim Nuclear Power Station.With ML20197J3591998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for Pilgrim Nuclear Power Station.With ML20195C9951998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for Pilgrim Nuclear Power Station.With ML20154K0721998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for Pilgrim Nuclear Power Station.With ML20153D3901998-09-22022 September 1998 Safety Evaluation Granting 970707 Request to Use Guidance in GL 90-05 to Repair Flaws in ASME Class 3 Salt Svc Water Sys Piping for Pilgrim Nuclear Power Station ML20197C5011998-09-0404 September 1998 Rev 12C,Pages 4 & 5 to Pilgrim Nuclear Power Station Colr ML20197C5471998-08-31031 August 1998 Rev 12C to Pilgrim Nuclear Power Station Colr ML20151W8231998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for Pilgrim Nuclear Power Station.With ML20237E2251998-08-26026 August 1998 Suppl & Revs to SE for Amend 173 for Pigrim Nuclear Power Station ML20237A9941998-07-31031 July 1998 Monthly Operating Rept for Pilgrim Nuclear Power Station ML20236U8201998-07-13013 July 1998 Rev 12B to Pilgrim Nuclear Power Station COLR (Cycle 12) ML20236P0151998-06-30030 June 1998 Monthly Operating Rept for June 1998 for Pilgrim Nuclear Power Station ML20249A3741998-05-31031 May 1998 Monthly Operating Rept for May 1998 for Pilgrim Nuclear Power Station.W/Undated Ltr ML20247H2081998-04-30030 April 1998 Monthly Operating Rept for Apr 1998 for Pilgrim Nuclear Power Station ML20207B7601998-03-31031 March 1998 Final Rept, Pilgrim Nuclear Power Station Site-Specific Offsite Radiological Emergency Preparedenss Prompt Alert & Notification System Quality Assurance Verification, Prepared for FEMA ML20216G3911998-03-31031 March 1998 Monthly Operating Rept for Mar 1998 for Pilgrim Nuclear Power Station ML20216J3741998-03-19019 March 1998 Safety Evaluation Accepting Licensee Request to Evaluate Elevated Tailpipe Temp on Safety Relief Valve SRV 203-3B ML20248L2241998-02-28028 February 1998 Monthly Operating Rept for Feb 1998 for Pilgrim Nuclear Station ML20202G5251998-01-31031 January 1998 Monthly Operating Rept for Jan 1998 for Pilgrim Nuclear Power Station ML20236M8511997-12-31031 December 1997 1997 Annual Rept for Boston Edison & Securities & Exchange Commission Form 10-K Rept ML20198L7701997-12-31031 December 1997 Monthly Operating Rept for Dec 1997 for Pilgrim Nuclear Power Station ML20203D6101997-11-30030 November 1997 Monthly Operating Rept for Nov 1997 for Pilgrim Nuclear Power Station ML20202D5761997-11-0808 November 1997 1997 Evaluated Exercise BECO-LTR-97-111, Monthly Operating Rept for Oct 1997 for Pilgrim Nuclear Power Station1997-10-31031 October 1997 Monthly Operating Rept for Oct 1997 for Pilgrim Nuclear Power Station ML20217D6431997-10-0101 October 1997 Safety Evaluation Granting Request for Approval to Repair Flaws in Accordance W/Gl 90-05 for ASME Class 3 SSW Piping for Pilgrim ML20217H5621997-09-30030 September 1997 Monthly Operating Rept for Sept 1997 for Pilgrim Nuclear Power Station ML20216J4131997-08-31031 August 1997 Monthly Operating Rept for Aug 1997 for Pilgrim Nuclear Power Station ML20210J3321997-07-31031 July 1997 Monthly Operating Rept for Jul 1997 for Pilgrim Nuclear Power Station 1999-09-08
[Table view] |
Text
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~ 10 CFR 50.73 sosnw amow Pilgrim Nuclear Itwer Stetson r Poc6 y Hill Road l Plymouth, Massachusetts 023f,0 i
Ralph G. Bird ,
Servor Vice President - Nuclear i
Mkrch 30, 1990 !
BECo Ltr. 90 045 l I
U.S. Nuclear Regulatory Connission ;
Attn: Document Control Desk '
Harhington, D.C. 20555 t
Docket No. 50-293 License No. DPR-35 l
Dear Sir:
The enclosed Licensee Event Report (LER) 90-002-00, " Contrary to Technical Specifications, Maximum Fraction of Limiting Power Oensity Not Checked and ,
Average Power Range Monitor Rod Block Not flow Blased in Refuel and Startup",
is submitted in accordance with 10 CFR Part 50.73. .
i Please do not hesitate to contact me if there are any questions regarding this :'
report.
h G 1 BPL/bal
Enclosure:
LER 90-002-00 !
cc: Mr. William Russell :
Regional Administrator, Region I l U.S. Nuclear Regulatory Commission .
475 Allendale Rd.
King of Prussia, PA 19406 l
Sr. NRC Resident Inspector - Pilgrim Station gggff8 '
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On February 28, 1990, it was determined that the Maximum Fraction of Limiting Power Density (MFLPD) was not checked daily during reactor power operation as required by Technical Specification (T.S.) 4.1.B. T.S.1.0.H defines reactor power operation as "any operation with the mode switch in the Startup or Run position with the reactor critical and above one percent design power". For several days in February and March, 1989, the Reactor Mode Selector Switch (RMSS) was in the Startup position and reactor power ranged between one and five percent. On those days, MFLPD was not checked.
On March 23, 1990, while reviewing the MfLPD issue, an additional T.S.
compliance issue was discovered. The operability requirements of T.S. 3.2.C and Table 3.2.C-1 were not met, when the RMSS was in the Startup or Refuel position. T.S. Amendment 110 (effective December 30, 1987) changed the operability requirements for the flow biased Average Power Range Monitor (APRM) rod block from Run mode to Refuel, Startup, and Run modes. The APRM rod block is not flow biased when the RMSS is in the Refuel or Startup position.
The Technical Specifications will be changed to be compatible with plant design and equipment capabilities.
There was no potential to adversely impact the public health and safety as a l
result of these events. When the RMSS was in the Refuel or Startup position, conservative APRM scram and rod block settings were achieved by the setdown function, at 13% and 11% reactor power respectively.
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nin nl9 0' nh r.n - . - -c w =. m EVENT DESCRIPTION On February 28, 1990, it was determined that the Maximum Fraction of Limiting Power Density (MFLPD) was not checked daily during reactor power operation, as required by Technical Specification (T.S.) 4.1.B. T.S. 1.0.H defines Reactor Power Operation as any operation with the Reactor Mode Selector Switch (RMSS) in the Startup or Run position, the reactor critical and above one percent power.
For several days in February, and March, 1989, the NFLPD was not checked. On those days, the RMSS was in the Startup position and reactor power was between one and five percent. The plant was operating at or below five percent reactor power in accordance with Pilgrim's Power Ascension Program.
On March 23, 1990, while reviewing the NFLPD issue, an additional T.S.
compliance issue was discovered. The operability requirements of T.S.3.2.C and Table 3.2.C-1 were not met, when the RMSS was in the Startup or Refuel positions, since December 30, 1987. T.S. Amendment 110 (effective December 30, 1987) changed the operability requirements of the flow biased APRM rod block from Run mode to Refuel, Startup and Run mode. The APRM rod block is not flow biased when the RMSS is in the Refuel or Startup position.
PLANT CONDITIONS AT TIME OF DISCOVERY On February 28, 1990, the RMSS was in the Run position, reactor power was at l 100 percent, reactor vessel pressure was 1027 psig, and the reactor vessel l water temperature was 547 degrees Fahrenheit.
On March 23, 1990, the RMSS was in the Shutdown position, reactor power was zero percent, reactor vessel pressure was zero, and the reactor vessel water temperature was approximately 100 degrees Fahrenheit.
BACKGROUND The MFLPD is checked to determine if the flow biased APRM scram and rod block set points require adjustment. Adjustment is necessary if the fraction of Rated Power (FRP) to MFLPD ratio is less than one. If the FRP/MFLPD is less than one, the flow biased APRM scram and rod block set points are adjusted per the following equations to prevent rod motion (rod block) or to shut down (scram) the reactor.
- Flow Blased APRM Scram Setting (2 loop operation)
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S = Setting in percent of rated thermal power (1998 megawatts ;
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H Percent of drive flow to produce a rated core flow of 69 i million Ib/hr. l
- Flow Blased APRM Rod Block Setting (2 loop operation)
SRB 1 (.5BN + 50%) [ 'M D t
Hhere, l SRB = Rod block setting in percent of rated thermal power (1998 ,
megawatts thermal). ;
H - Percent of drive flow to produce a rated core flow of 69 ;
million Ib/hr. ;
In accordance with plant design and installed configuration, the APRM scram !
and rod block are flow biased when the RMS$ is in the Run position. When the l RMSS is in the Refuel or Startup position, the APRM scram and rod block are !
set down and are not flow biased as the December, 1987 T.S. change indicates.
The APRM scram is set down in accordance with T.S. 2.1.A.I.b (required i 15%) {
and is calibrated in accordance with Procedure 8.M.1-3.1 "APRM Set Down i Functional" at 13% (12.5% - 13.5%). The set down APRM rod block is calibrated i in accordance with Procedure 8.M.1-3.1 at 11% (10.5% - 11.5%). The set down APRM rod block is not addressed by the Technical Specifications. [
t MFLPD is checked daily when reactor power is 1 10 % in accordance with i Procedure 2.1.15 " Daily Surveillance Log". The P-1 program of the Process i Computer performs the MFLPD calculations. The program determines NFLPD at a :
particular fuel rod axial segment based on readings from the Local Power Range t
, Monitors (LPRMs). The P-1 program does not function below 10% reactor power.
1
, CAUSE i 1 t l The requirement to check MFLPD daily during reactor power operation (T.S.
l 4.1.B) was inconsistent with equipment capabilities and plant procedures. ;
Procedure 2.1.15 requires MFLPD to be checked daily when reactor power is .
greater than 10%. This is consistent with the capability of the P-1 program l of the Process Computer. Typically, reactor power is increased from 1% to 10%
in less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, in which case, compliance with T.S. 4.1.B was 4 achieved. In FeLruary and March, 1989, an unusual circumstance existed when reactor power ranged between 1% and 5% for several days with the RMSS in the Startup position. The plant was operating at or below 5% reactor power in accordance with Pilgrim's Power Ascension Program, i !
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l The flow biased APRM rod block operational requirements (RMS$ in Refuel, .
Startup, and Run positions) were inconsistent with the plant design and i installed configuration. The operability requirements for the flow biased i APRM rod block were revised in T.S. Amendment 110, effective December 30, !
1987. Prior to Amendment 110, operability of the flow biased APRM rod block l was only required when the RMSS was in the Run position and was consistent !
with the operability requirement for the flow biased APRM scram (T.S. l 2.1.A.l.4). l CORRECTIVE ACTIONS
- The Technical Specifications 3.2.C and 4.1.8 will be changed, so the T.S. requirements match the plant's configuration and equipment i capabilities. l
- A T.S. review is ongoing (Long Term Plan No. 468) as part of Pilgrim's involvement in the BHR Owners Group Improved Technical !
Specifications program. If other similar T.S. compliance problems i exist, this review will identify them. l e Unrelated to this event, the Compliance Division established a .
process to independently review T.S. changes for impact on operating i procedures in February, 1989.
SAFETY ONSEOUENCES/ SIGNIFICANCE ;
There were no adverse safety consequences for these situations. [
When the RMSS is in the Refuel or Startup position, the set down APRM scram i
- and rod block fJnctions are set at 13% and 11% of rated reactor power j respectively. These settings are far lower than could reasonably be achieved '
by adjusting the flow biased APRM scram and rod block setting per the !
l FRP/MFLPD ratio. In fact, adjustment of the flow biased APRM scram and rod ,
block settings has no affect on the scram or rod block function when the RMSS l is in the Refuel or Startup position, because these functions are not in i circuit. 1 l
The Intermediate Range Monitor System (IRMS) scram and rod block functions are i a backup to the set down APRM scram and rod block functions when the RMSS is l in the Refuel or Startup position. Each IRM has 10 ranges. The ranges are l ,
! selected to monitor neutron flux from slightly above 0% reactor power to 32% 1 l reactor power. The IRM scram is set at i 120 on the 125% full scale. The IRM l l rod block is set at i 108 on the 125% full scale.
l l Additional protection is provided by the Rod Horth Minimizer (RHM) function of :
the Process Computer System. The RHM can initiate a tod insert block, a rod withdrawal block and a rod select block. The RHM functions to reinforce procedural controls that limit the reactivity worth of control rods under low '
power conditions. Adherence to prescribed control rod patterns is the procedural method by which this reactivity restriction is observed.
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0l 0 0l 5 of 0l5 These situations had no potential to adversely impact the public health and safety.
REPORTABILITY The plant was operating in conditions prohibited by the Technical Specifications. The events are reportable per 10 CFR 50.73(a)(2)(1). Failure and Malfunction Report No. 90-13 was written to document the apparent T.S.
compliance problem.
SIMILARITY TO PREVIOUS EVENTS A review of t.icensee Event Reports submitted since January 1984, in accordance with 10CFR 50.73(a)(2)(1) was conducted. No similar events were identified in which a T.S. could not be met because the requirement was incorrect relative to the plent design and installed configuration.
ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) CODES Comoonents Codes Meter MTR Monitor MON Rod ROD Systems Computer System IS Incore/Excore Monitoring System IG l
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