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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20029D0201994-04-25025 April 1994 LER 94-007-01:on 931014,high Head Safety Injection Flow Balance Testing Found to Be Below TS Requirement.Caused by Unaccounted for Uncertainties.Cold Leg Safety Injection Leg Throttle Valve adjusted.W/940425 Ltr ML20045G9391993-07-0808 July 1993 Lr 93-017-00:on 930616,containment Hydrogen Analyzer Heat Trace Channel Calibration Not Performed on Staggered Test Basis Due to Inadequate Implementation of TS Amend.Test Procedure Satisfactorily performed.W/930708 Ltr ML20044H1591993-05-27027 May 1993 LER 93-016-00:on 930509,discovered That Containment Hydrogen Analyzer Pressure Switch PS-3 Sensing Line Disconnected in Local Panel.Caused by Personnel Error. Pressure Switch Calibr & Line reconnected.W/930527 Ltr ML20044D5711993-05-14014 May 1993 LER 93-002-00:on 930416,automatic Reactor Trip Initiated from Turbine Trip Due to Over Excitation of Main Generator. Emergency Procedure 2-E-0 Entered & Individuals Involved in Event Received Remediated training.W/930514 Ltr ML20044D2281993-05-12012 May 1993 LER 93-003-00:on 930424,manual Reactor Trip Initiated Due to Erratic Feedwater Flow Indications to SG C & Excessive Main Feedwater Regulating Valve Oscillations.Caused by Design Instabilities.Secondary Sys secured.W/930512 Ltr ML20044C9541993-05-0707 May 1993 LER 93-015-00:on 930427,discovered That Portions of Containment Pressure Channels That Input to Containment Spray hi-hi Pressure Not Tested Monthly.Caused by Personnel Error.Test Procedures changed.W/930507 Ltr ML20044C9811993-05-0606 May 1993 LER 93-014-00:on 930411,as-found Speed Setting of Steam Driven AFW Pump 1-FW-P-2 Found Below Required TS Limit. Caused by Incorrect Speed Control Setting.Pump Speed Adjusted & Maint Personnel counseled.W/930506 Ltr ML20024G6841991-04-18018 April 1991 LER 91-006-00:on 910403,discovered That Ac Offsite Power Source Surveillance Not Performed Due to Personnel Error. Surveillance Initiated Immediately & Positive Discipline Administered to supervisor.W/910418 Ltr ML20029B5601991-03-0606 March 1991 LER 91-005-00:on 910209,containment Building Penetrations Breached.Caused by Inadequate Procedural Controls.Core Mapping & Cavity Pump Down Activities Secured,Air Hose Removed & Hydrolase Hose capped.W/910306 Ltr ML20029A6471991-02-22022 February 1991 LER 91-004-00:on 910206,sealed Radioactive Source in Storage Not Leak Tested Prior to Use.Caused by Inadequate Procedures for Verifying Leak Testing of Sources.Procedures Revised.W/ 910222 Ltr ML20028H6681991-01-18018 January 1991 LER 90-009-01:on 900719,discovered That Response Time Testing of Pressurizer High Level Reactor Trip Function Not Performed in Accordance W/Tech Spec 3.3.1.1,Table 3.3-2. Caused by Personnel Error.Procedures revised.W/910118 Ltr ML20043H8321990-06-22022 June 1990 LER 90-007-00:on 900523,discovered That Two Sets of Concrete Roof Blocks on Svc Water Pump House Not in Required Safety Position.Caused by Lack of Administrative Controls.Blocks Restored to Required locations.W/900622 Ltr ML20043D5801990-06-0404 June 1990 LER 90-006-00:on 900504,casing Cooling Pump Not Put Into Alert Status & Surveillance Missed.Caused by Personnel Error.Pump 1-RS-P-3B Placed in Alert status.W/900604 Ltr ML20012E3301990-03-27027 March 1990 LER 90-003-00:on 900228,52 Valves Identified Not Included in Tech Spec Required Monthly Containment Integrity Verification Surveillance Program.Caused by Personnel Error & Inadequate Procedure.Procedure revised.W/900327 Ltr ML20012B6441990-03-0808 March 1990 LER 90-001-00:on 900215,inadvertent Partial Train a ESF Actuation of Containment Depressurization Sys Occurred. Caused by Human Error.Evaluation to Be Performed to Determine If Test Points Can Be moved.W/900308 Ltr ML20006E2371990-02-0808 February 1990 LER 90-001-00:on 900123,reactor Trip Occurred on Steam Feedwater Flow Mismatch.Caused by Failed Circuit Driver Card on Feedwater Regulating Valve.Feedwater Regulating Valve Driver Card replaced.W/900208 Ltr ML20006E3771990-02-0505 February 1990 LER 90-002-00:on 900127,fuel Bldg Ventilation Sys Not Aligned to Discharge Through Auxiliary Bldg HEPA Filter & Charcoal Adsorber Assembly During Fuel Movement.Caused by Personnel Error.Disciplinary Action taken.W/900205 Ltr ML20006A8531990-01-19019 January 1990 LER 89-019-00:on 891228,discovered That Outer Door of Containment Equipment Escape Air Lock Was Drawing in Air & Inner Door Noted as Not Being in Fully Closed Position.Cause Undetermined.Sys Enhancements Being evaluated.W/900119 Ltr ML20005F8781990-01-11011 January 1990 LER 89-018-00:on 891219,determined That Three Pressurizer Pressure Safety Injection Instrumentation Channels May Not Have Adequate Margin Between Actuation Setpoint & Bottom of Instrument span.W/900111 Ltr ML19332D5471989-11-22022 November 1989 LER 85-003-03:on 890907,determined That Situation Could Arise Where Water Level Would Rise to 264 Ft Before Next Required Surveillance Interval.Cause Not Determined.Dike to Be constructed.W/891122 Ltr ML20024B7821983-07-0606 July 1983 LER 83-048/03L-0:on 830606 & 17,intermediate Range Channels N35 & N36 High Neutron Flux Reactor Trip Setpoints Exceeded Tech Spec Requirements.Caused by Administrative Error. Setpoints reduced.W/830706 Ltr ML20024C1361983-06-30030 June 1983 LER 83-031/03L-0:on 830614,w/unit at 100% Power,Fire Door S54/5 from Emergency Switchgear Room to Cable Vault Would Not Latch.Fire Watch Posted Immediately.Caused by Misaligned Strike.Door Repaired within 1 h.W/830630 Ltr ML20024C3721983-06-30030 June 1983 LER 83-042/03L-0:on 830606,vital Bus 1-I Momentarily Deenergized While Trying to Clear Inverter Trouble Alarm. Caused by Operator Error.Bus energized.W/830630 Ltr ML20024B9891983-06-28028 June 1983 LER 83-047/03L-0:on 830530,emergency Diesel Generator 2J Tripped on High Crankcase Pressure During Surveillance Testing.Cause Not Determined.Diesel Tested Satisfactorily. W/830628 Ltr ML20024C2941983-06-23023 June 1983 LER 83-044/03L-0:on 830526,during Mode 3,one Recirculation Valve on Each of Two Casing Cooling Pumps Found Open.Caused by Procedure Inadequacy.Valves Closed Immediately.Maint Procedure Will Be revised.W/830623 Ltr ML20024C3071983-06-22022 June 1983 LER 83-034/03L-0:on 830525,during Mode 1,one Header of Control Room Bottled Air Pressurized Sys Had Lower than Required Pressure.Probably Caused by Leak from B Bank of Air Bottles.Header repressurized.W/830622 Ltr ML20024C0971983-06-22022 June 1983 LER 83-045/03L-0:on 830614,Fire Door S71-18,between Emergency Diesel Generator Room 2H & Turbine Bldg,Would Not Latch & Lock.Caused by Stuck Latch.Latch Adjusted & Lubricated.Door Designs modified.W/830622 Ltr ML20023E0951983-06-0101 June 1983 LER 83-027/03L-0:on 830505,one Header (42 Bottles) of Control Room Bottled Air Pressurized Sys Found to Have Lower than Required Pressure (2,290 Vs 2,300 Psig).Probably Caused by Leakage When Compressor malfunctioned.W/830601 Ltr ML20023E0721983-05-26026 May 1983 LER 83-029/03L-0:on 830509,following Rapid Rampdown from 100% to 4% power,I-131 Dose Equivalent Exceeded 1.0 Uci/G. Caused by Unidentified Fuel Element Defect Worsened by post-rampdown Conditions.Sampling increased.W/830526 Ltr ML20023D5371983-05-13013 May 1983 LER 83-022/03L-0:on 830412,review of ASME XI Iwv Program Identified 192 Valves Not Exercised &/Or Stroke Timed.Caused by Fragmented Implementation of Testing Program.Programs Upgraded ML20023D2491983-05-11011 May 1983 LER 83-032/03L-0:on 830412,during Mode 5,visual Insp of Hydraulic Snubber 2-WGCB-HSS-3B Revealed Damaged Reservoir W/O Fluid.Caused by Personnel Working in Area.Snubber Replaced ML20023C5371983-05-10010 May 1983 LER 83-021/03L-0:on 830411,Fire Door S-71-7 Between Svc Bldg Health Physics Area & Auxiliary Bldg Would Not Self Close.Caused by Removal of Reclosure Device for Maint of Closure Coupling.Reclosure Device Reinstalled ML20023B5931983-04-27027 April 1983 LER 83-029/03L-0:on 830402,during Mode 4,automatic Actuation of ECCS Occurred.Caused by Maint Personnel Standing on Conduit Resulting in Loss of lo-lo Pressurizer Pressure Safety Injection Block.Maint Personnel Reinstructed ML20023B5701983-04-27027 April 1983 LER 83-008/03L-0:on 830410,review Revealed That Procedure Used to Restore Boron Injection Tank Concentration Introduced Potential Unanalyzed Injection Flow Diversions. Caused by Oversight.Emergency Procedures Revised ML20028G6541983-02-0909 February 1983 LER 83-003/03L-0:on 830122,during Mode 5,RHR Flow Was Lost for 4 Minutes.Caused by Failure of 15 Kv a Inverter to Ac Vital Bus 1-III,de-energizing Auxiliary Relay for Pressure Channel P-1403.Vital Bus 1-III & RHR Flow Restored ML20028G6311983-02-0909 February 1983 LER 83-016/03L-0:on 830115 & 16,both Open & Closed Containment Isolation Valves TV-SI-200 & TV-CC-204C,train a Position Indication Lights Found Lit.Caused by Leaking Steam Generator Chemical Feed Line Vent Valve ML20028G0781983-01-31031 January 1983 LER 83-001/03L-0:on 830112,primary Grade Water Isolation Valve to Blender 1-CH-217 Remained Open Longer than Tech Spec Requirements.Caused by Personnel Error.Responsible Operator Reinstructed ML20028G0381983-01-28028 January 1983 LER 83-002/03L-0:on 830104,two of Four 2H Emergency Diesel Generator Surveillance Tests Required by Tech Spec Missed During Nov-Dec 1982.Caused by Scheduling Error.Test Frequency Increased to Meet Tech Spec Requirements ML20028G0131983-01-28028 January 1983 LER 83-011/03L-0:on 821119,individual Rod Position Indication Deviated from Group Demand Position by Greater than 12 Steps.Caused by Instrument Drift.Indicator Channel for Rods B-09 & 02 & F-06 Recalibr ML20028F3501983-01-19019 January 1983 LER 83-008/03L-0:on 830107,during Mode 3,individual Rod Position Indication Deviated from Group Demand Position by Greater than 12 Steps While Withdrawing Shutdown Bank B. Caused by Instrument Drift.Rods Recalibr ML20028E0391983-01-11011 January 1983 Updated LER 82-079/03X-1:on 821126,flow Path from Boric Acid Tanks to RCS Found Inoperable.Caused by Ruptured Diaphragm of Boric Acid Transfer Pump Suction Header Isolation Valve 1-CH-80.Valve Diaphragm Replaced ML20028E0441983-01-11011 January 1983 LER 82-085/03L-0:on 821215,w/unit at Full Power,Emergency Diesel Generator 2J Removed from Svc for 7 H to Adjust Voltage Regulator Response Time.Caused by Voltage Regulator Drift.Procedures Will Be Revised ML20028E0201983-01-11011 January 1983 LER 82-084/03L-0:on 821216,during Full Power,Input from Range Nuclear Instrument N-42 to Comparator Drawer N-50 Was in Defeat.Caused by Failure to Take N-42 Out of Defeat After Deviation Alarm Determination.Operators to Be Reinstructed ML20028E0781983-01-11011 January 1983 LER 82-078/03X-1:on 821125,w/unit in Mode 3,120-volt Ac Vital Bus 1-IV Lost Voltage.Caused by Failure of Normal Power Supply Inverter 1-VB-I-04,due to Failed Oscillator Board,Transformer & Fuse.Components Replaced ML20028D1311983-01-0505 January 1983 LER 82-083/03L-0:on 821213,emergency Diesel Generator 2J Removed from Svc.Caused by Failure of 40X Unexcitation Alarm Relay Coil.Carbon Deposits & Arcing Damage of 40/76 Relay Contact Prevented Good Contact ML20028D1571983-01-0505 January 1983 Updated LER 81-071/03X-2:on 810911,hydraulic Snubber on Main Steam Line Discovered Inoperable Due to Loss of Oil from Reservoir.Caused by Leak Due to Scored Brass Bushing on Piston Shaft.Snubber Purged & Refilled.Reach Rod Retorqued ML20028C5191982-12-31031 December 1982 LER 82-083/03L-0:on 821204,while Operating at 17% Rated Thermal Power,Turbine Control Sys Malfunctioned Causing Sudden Increase in Load,Resulting in Reactor Trip.Caused by Malfunction of Analog Converter ML20028A8651982-11-16016 November 1982 LER 82-067/03L-0:on 821019,suction to RHR Sys Pumps a & B Lost for 36 Minutes.On 821020,pump Suction Lost for 33 Minutes.Caused by Ambiguous RCS Level Indication While Water Drained to Centerline of Nozzles.Water Added ML20028A8821982-11-16016 November 1982 LER 82-060/03L-0:on 821019,station Battery I-IV Failed 18- Month Discharge Surveillance Test.Caused by Natural End of Life.Battery Replaced ML20028A9781982-11-16016 November 1982 LER 82-071/03L-0:on 821027,control Power for B Casing Cooling Pump Found de-energized.Caused by Opened Circuit Breaker Unintentionally Disturbed by Workers.Circuit Breaker Closed & Power Verified 1994-04-25
[Table view] Category:RO)
MONTHYEARML20029D0201994-04-25025 April 1994 LER 94-007-01:on 931014,high Head Safety Injection Flow Balance Testing Found to Be Below TS Requirement.Caused by Unaccounted for Uncertainties.Cold Leg Safety Injection Leg Throttle Valve adjusted.W/940425 Ltr ML20045G9391993-07-0808 July 1993 Lr 93-017-00:on 930616,containment Hydrogen Analyzer Heat Trace Channel Calibration Not Performed on Staggered Test Basis Due to Inadequate Implementation of TS Amend.Test Procedure Satisfactorily performed.W/930708 Ltr ML20044H1591993-05-27027 May 1993 LER 93-016-00:on 930509,discovered That Containment Hydrogen Analyzer Pressure Switch PS-3 Sensing Line Disconnected in Local Panel.Caused by Personnel Error. Pressure Switch Calibr & Line reconnected.W/930527 Ltr ML20044D5711993-05-14014 May 1993 LER 93-002-00:on 930416,automatic Reactor Trip Initiated from Turbine Trip Due to Over Excitation of Main Generator. Emergency Procedure 2-E-0 Entered & Individuals Involved in Event Received Remediated training.W/930514 Ltr ML20044D2281993-05-12012 May 1993 LER 93-003-00:on 930424,manual Reactor Trip Initiated Due to Erratic Feedwater Flow Indications to SG C & Excessive Main Feedwater Regulating Valve Oscillations.Caused by Design Instabilities.Secondary Sys secured.W/930512 Ltr ML20044C9541993-05-0707 May 1993 LER 93-015-00:on 930427,discovered That Portions of Containment Pressure Channels That Input to Containment Spray hi-hi Pressure Not Tested Monthly.Caused by Personnel Error.Test Procedures changed.W/930507 Ltr ML20044C9811993-05-0606 May 1993 LER 93-014-00:on 930411,as-found Speed Setting of Steam Driven AFW Pump 1-FW-P-2 Found Below Required TS Limit. Caused by Incorrect Speed Control Setting.Pump Speed Adjusted & Maint Personnel counseled.W/930506 Ltr ML20024G6841991-04-18018 April 1991 LER 91-006-00:on 910403,discovered That Ac Offsite Power Source Surveillance Not Performed Due to Personnel Error. Surveillance Initiated Immediately & Positive Discipline Administered to supervisor.W/910418 Ltr ML20029B5601991-03-0606 March 1991 LER 91-005-00:on 910209,containment Building Penetrations Breached.Caused by Inadequate Procedural Controls.Core Mapping & Cavity Pump Down Activities Secured,Air Hose Removed & Hydrolase Hose capped.W/910306 Ltr ML20029A6471991-02-22022 February 1991 LER 91-004-00:on 910206,sealed Radioactive Source in Storage Not Leak Tested Prior to Use.Caused by Inadequate Procedures for Verifying Leak Testing of Sources.Procedures Revised.W/ 910222 Ltr ML20028H6681991-01-18018 January 1991 LER 90-009-01:on 900719,discovered That Response Time Testing of Pressurizer High Level Reactor Trip Function Not Performed in Accordance W/Tech Spec 3.3.1.1,Table 3.3-2. Caused by Personnel Error.Procedures revised.W/910118 Ltr ML20043H8321990-06-22022 June 1990 LER 90-007-00:on 900523,discovered That Two Sets of Concrete Roof Blocks on Svc Water Pump House Not in Required Safety Position.Caused by Lack of Administrative Controls.Blocks Restored to Required locations.W/900622 Ltr ML20043D5801990-06-0404 June 1990 LER 90-006-00:on 900504,casing Cooling Pump Not Put Into Alert Status & Surveillance Missed.Caused by Personnel Error.Pump 1-RS-P-3B Placed in Alert status.W/900604 Ltr ML20012E3301990-03-27027 March 1990 LER 90-003-00:on 900228,52 Valves Identified Not Included in Tech Spec Required Monthly Containment Integrity Verification Surveillance Program.Caused by Personnel Error & Inadequate Procedure.Procedure revised.W/900327 Ltr ML20012B6441990-03-0808 March 1990 LER 90-001-00:on 900215,inadvertent Partial Train a ESF Actuation of Containment Depressurization Sys Occurred. Caused by Human Error.Evaluation to Be Performed to Determine If Test Points Can Be moved.W/900308 Ltr ML20006E2371990-02-0808 February 1990 LER 90-001-00:on 900123,reactor Trip Occurred on Steam Feedwater Flow Mismatch.Caused by Failed Circuit Driver Card on Feedwater Regulating Valve.Feedwater Regulating Valve Driver Card replaced.W/900208 Ltr ML20006E3771990-02-0505 February 1990 LER 90-002-00:on 900127,fuel Bldg Ventilation Sys Not Aligned to Discharge Through Auxiliary Bldg HEPA Filter & Charcoal Adsorber Assembly During Fuel Movement.Caused by Personnel Error.Disciplinary Action taken.W/900205 Ltr ML20006A8531990-01-19019 January 1990 LER 89-019-00:on 891228,discovered That Outer Door of Containment Equipment Escape Air Lock Was Drawing in Air & Inner Door Noted as Not Being in Fully Closed Position.Cause Undetermined.Sys Enhancements Being evaluated.W/900119 Ltr ML20005F8781990-01-11011 January 1990 LER 89-018-00:on 891219,determined That Three Pressurizer Pressure Safety Injection Instrumentation Channels May Not Have Adequate Margin Between Actuation Setpoint & Bottom of Instrument span.W/900111 Ltr ML19332D5471989-11-22022 November 1989 LER 85-003-03:on 890907,determined That Situation Could Arise Where Water Level Would Rise to 264 Ft Before Next Required Surveillance Interval.Cause Not Determined.Dike to Be constructed.W/891122 Ltr ML20024B7821983-07-0606 July 1983 LER 83-048/03L-0:on 830606 & 17,intermediate Range Channels N35 & N36 High Neutron Flux Reactor Trip Setpoints Exceeded Tech Spec Requirements.Caused by Administrative Error. Setpoints reduced.W/830706 Ltr ML20024C1361983-06-30030 June 1983 LER 83-031/03L-0:on 830614,w/unit at 100% Power,Fire Door S54/5 from Emergency Switchgear Room to Cable Vault Would Not Latch.Fire Watch Posted Immediately.Caused by Misaligned Strike.Door Repaired within 1 h.W/830630 Ltr ML20024C3721983-06-30030 June 1983 LER 83-042/03L-0:on 830606,vital Bus 1-I Momentarily Deenergized While Trying to Clear Inverter Trouble Alarm. Caused by Operator Error.Bus energized.W/830630 Ltr ML20024B9891983-06-28028 June 1983 LER 83-047/03L-0:on 830530,emergency Diesel Generator 2J Tripped on High Crankcase Pressure During Surveillance Testing.Cause Not Determined.Diesel Tested Satisfactorily. W/830628 Ltr ML20024C2941983-06-23023 June 1983 LER 83-044/03L-0:on 830526,during Mode 3,one Recirculation Valve on Each of Two Casing Cooling Pumps Found Open.Caused by Procedure Inadequacy.Valves Closed Immediately.Maint Procedure Will Be revised.W/830623 Ltr ML20024C3071983-06-22022 June 1983 LER 83-034/03L-0:on 830525,during Mode 1,one Header of Control Room Bottled Air Pressurized Sys Had Lower than Required Pressure.Probably Caused by Leak from B Bank of Air Bottles.Header repressurized.W/830622 Ltr ML20024C0971983-06-22022 June 1983 LER 83-045/03L-0:on 830614,Fire Door S71-18,between Emergency Diesel Generator Room 2H & Turbine Bldg,Would Not Latch & Lock.Caused by Stuck Latch.Latch Adjusted & Lubricated.Door Designs modified.W/830622 Ltr ML20023E0951983-06-0101 June 1983 LER 83-027/03L-0:on 830505,one Header (42 Bottles) of Control Room Bottled Air Pressurized Sys Found to Have Lower than Required Pressure (2,290 Vs 2,300 Psig).Probably Caused by Leakage When Compressor malfunctioned.W/830601 Ltr ML20023E0721983-05-26026 May 1983 LER 83-029/03L-0:on 830509,following Rapid Rampdown from 100% to 4% power,I-131 Dose Equivalent Exceeded 1.0 Uci/G. Caused by Unidentified Fuel Element Defect Worsened by post-rampdown Conditions.Sampling increased.W/830526 Ltr ML20023D5371983-05-13013 May 1983 LER 83-022/03L-0:on 830412,review of ASME XI Iwv Program Identified 192 Valves Not Exercised &/Or Stroke Timed.Caused by Fragmented Implementation of Testing Program.Programs Upgraded ML20023D2491983-05-11011 May 1983 LER 83-032/03L-0:on 830412,during Mode 5,visual Insp of Hydraulic Snubber 2-WGCB-HSS-3B Revealed Damaged Reservoir W/O Fluid.Caused by Personnel Working in Area.Snubber Replaced ML20023C5371983-05-10010 May 1983 LER 83-021/03L-0:on 830411,Fire Door S-71-7 Between Svc Bldg Health Physics Area & Auxiliary Bldg Would Not Self Close.Caused by Removal of Reclosure Device for Maint of Closure Coupling.Reclosure Device Reinstalled ML20023B5931983-04-27027 April 1983 LER 83-029/03L-0:on 830402,during Mode 4,automatic Actuation of ECCS Occurred.Caused by Maint Personnel Standing on Conduit Resulting in Loss of lo-lo Pressurizer Pressure Safety Injection Block.Maint Personnel Reinstructed ML20023B5701983-04-27027 April 1983 LER 83-008/03L-0:on 830410,review Revealed That Procedure Used to Restore Boron Injection Tank Concentration Introduced Potential Unanalyzed Injection Flow Diversions. Caused by Oversight.Emergency Procedures Revised ML20028G6541983-02-0909 February 1983 LER 83-003/03L-0:on 830122,during Mode 5,RHR Flow Was Lost for 4 Minutes.Caused by Failure of 15 Kv a Inverter to Ac Vital Bus 1-III,de-energizing Auxiliary Relay for Pressure Channel P-1403.Vital Bus 1-III & RHR Flow Restored ML20028G6311983-02-0909 February 1983 LER 83-016/03L-0:on 830115 & 16,both Open & Closed Containment Isolation Valves TV-SI-200 & TV-CC-204C,train a Position Indication Lights Found Lit.Caused by Leaking Steam Generator Chemical Feed Line Vent Valve ML20028G0781983-01-31031 January 1983 LER 83-001/03L-0:on 830112,primary Grade Water Isolation Valve to Blender 1-CH-217 Remained Open Longer than Tech Spec Requirements.Caused by Personnel Error.Responsible Operator Reinstructed ML20028G0381983-01-28028 January 1983 LER 83-002/03L-0:on 830104,two of Four 2H Emergency Diesel Generator Surveillance Tests Required by Tech Spec Missed During Nov-Dec 1982.Caused by Scheduling Error.Test Frequency Increased to Meet Tech Spec Requirements ML20028G0131983-01-28028 January 1983 LER 83-011/03L-0:on 821119,individual Rod Position Indication Deviated from Group Demand Position by Greater than 12 Steps.Caused by Instrument Drift.Indicator Channel for Rods B-09 & 02 & F-06 Recalibr ML20028F3501983-01-19019 January 1983 LER 83-008/03L-0:on 830107,during Mode 3,individual Rod Position Indication Deviated from Group Demand Position by Greater than 12 Steps While Withdrawing Shutdown Bank B. Caused by Instrument Drift.Rods Recalibr ML20028E0391983-01-11011 January 1983 Updated LER 82-079/03X-1:on 821126,flow Path from Boric Acid Tanks to RCS Found Inoperable.Caused by Ruptured Diaphragm of Boric Acid Transfer Pump Suction Header Isolation Valve 1-CH-80.Valve Diaphragm Replaced ML20028E0441983-01-11011 January 1983 LER 82-085/03L-0:on 821215,w/unit at Full Power,Emergency Diesel Generator 2J Removed from Svc for 7 H to Adjust Voltage Regulator Response Time.Caused by Voltage Regulator Drift.Procedures Will Be Revised ML20028E0201983-01-11011 January 1983 LER 82-084/03L-0:on 821216,during Full Power,Input from Range Nuclear Instrument N-42 to Comparator Drawer N-50 Was in Defeat.Caused by Failure to Take N-42 Out of Defeat After Deviation Alarm Determination.Operators to Be Reinstructed ML20028E0781983-01-11011 January 1983 LER 82-078/03X-1:on 821125,w/unit in Mode 3,120-volt Ac Vital Bus 1-IV Lost Voltage.Caused by Failure of Normal Power Supply Inverter 1-VB-I-04,due to Failed Oscillator Board,Transformer & Fuse.Components Replaced ML20028D1311983-01-0505 January 1983 LER 82-083/03L-0:on 821213,emergency Diesel Generator 2J Removed from Svc.Caused by Failure of 40X Unexcitation Alarm Relay Coil.Carbon Deposits & Arcing Damage of 40/76 Relay Contact Prevented Good Contact ML20028D1571983-01-0505 January 1983 Updated LER 81-071/03X-2:on 810911,hydraulic Snubber on Main Steam Line Discovered Inoperable Due to Loss of Oil from Reservoir.Caused by Leak Due to Scored Brass Bushing on Piston Shaft.Snubber Purged & Refilled.Reach Rod Retorqued ML20028C5191982-12-31031 December 1982 LER 82-083/03L-0:on 821204,while Operating at 17% Rated Thermal Power,Turbine Control Sys Malfunctioned Causing Sudden Increase in Load,Resulting in Reactor Trip.Caused by Malfunction of Analog Converter ML20028A8651982-11-16016 November 1982 LER 82-067/03L-0:on 821019,suction to RHR Sys Pumps a & B Lost for 36 Minutes.On 821020,pump Suction Lost for 33 Minutes.Caused by Ambiguous RCS Level Indication While Water Drained to Centerline of Nozzles.Water Added ML20028A8821982-11-16016 November 1982 LER 82-060/03L-0:on 821019,station Battery I-IV Failed 18- Month Discharge Surveillance Test.Caused by Natural End of Life.Battery Replaced ML20028A9781982-11-16016 November 1982 LER 82-071/03L-0:on 821027,control Power for B Casing Cooling Pump Found de-energized.Caused by Opened Circuit Breaker Unintentionally Disturbed by Workers.Circuit Breaker Closed & Power Verified 1994-04-25
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217N9281999-10-20020 October 1999 Special Rept:On 991003,PZR PORV Actuation Mitigated RCS low- Temp Overpressure Transient.Caused by a RCP Facilitating Sweeping of Entrained Air Out of RCS Loops.Operating Procedure 2-OP-5.1 Will Be Revised ML20217H3631999-10-14014 October 1999 Rev 0 to COLR for North Anna 2 Cycle 14 Pattern Su ML18152A2811999-10-12012 October 1999 Technical Basis for Elimination of Nozzle Inner Radius Insps (for Nozzles Other than Reactor Vessel),Technical Basis for ASME Section XI Code Case N-619. ML20212J9251999-10-0101 October 1999 Safety Evaluation Accepting Licensee Relief Request IWE-3 for Second 10-year ISI for Plant ML20217D6851999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for North Anna Power Station,Units 1 & 2.With ML20211N2611999-09-0808 September 1999 Safety Evaluation Concluding That Proposed Irradiation of Fuel Rods Beyond Current Lead Rod Burnup Limit & Clarification of Terminology with Respect to Reconstituted Fuel Assemblies Acceptable ML20211J2561999-08-31031 August 1999 Safety Evaluation Accepting Elimination of Augmented ISI Program for Pressurizer Spray Lines at North Anna Unit 2 ML20216E5011999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for Naps,Units 1 & 2. with ML20211J2421999-08-31031 August 1999 Safety Evaluation Supporting Removal of Augmented Insp Program on RCS Bypass Lines from Licensing Basis of North Anna,Units 1 & 2 ML20210T0791999-08-13013 August 1999 Safety Evaluation Concluding That Revised Withdrawal Schedules for North Anna Units 1 & 2 Satisfy Requirements of App H to 10CFR50 & Therefore Acceptable ML20210S1411999-07-31031 July 1999 Monthly Operating Repts for July 1999 for North Anna Power Station.With ML20210Q9931999-07-31031 July 1999 Rev 1 to COLR for North Anna Power Station,Unit 2 Cycle 13 Pattern Ud ML20209E5641999-06-30030 June 1999 Monthly Operating Repts for June 1999 for North Anna Power Stations,Units 1 & 2.With ML20195G1901999-05-31031 May 1999 Monthly Operating Rept for May 1999 for NAPS Units 1 & 2. with ML20206L4831999-05-10010 May 1999 SER Accepting Request to Delay Submitting Plant,Unit 1 Class 1 Piping ISI Program for Third Insp Interval Until 010430, to Permit Development of Risk Informed ISI Program for Class 1 Piping ML20206Q6671999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for North Anna Power Station,Units 1 & 2.With ML20205S0391999-04-21021 April 1999 SER Accepting Request for Relief IWE5,per 10CFR50.55a(a)(3) & Proposed Alternatives for IWE2,IWE4,IWE6 & IWL2 Authorized Per 10CFR50.55a(a)(3)(ii) ML20205K3041999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for North Anna Power Station,Units 1 & 2.With ML20207K5921999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for North Anna Power Station,Units 1 & 2.With ML20207E1731999-02-18018 February 1999 Informs Commission of Status of Preparations of IAEA Osart Mission to North Anna Nuclear Power Plant Early Next Year ML20205A0241998-12-31031 December 1998 Summary of Facility Changes,Tests & Experiments,Including Summary of SEs Implemented at Plant During 1998,per 10CFR50.59(b)(2).With ML20199C8781998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for North Anna Power Station,Units 1 & 2.With ML20198H9541998-12-0303 December 1998 Safety Evaluation Authorizing Proposed Alternative for Remainder of Second 10-yr Insp Interval for Plant ML20198J5561998-12-0303 December 1998 ISI Summary Rept for North Anna Power Station,Unit 1 1998 Refueling Outage Owner Rept for Inservice Insps ML20197G8551998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for North Anna Power Station,Units 1 & 2.With ML20196G1381998-11-0303 November 1998 Safety Evaluation Authorizing Rev to Relief Request NDE-32 for Remainder of Second 10-yr Insp Interval for Each Unit ML20195D0571998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for North Anna Power Station,Units 1 & 2.With ML20154L0691998-10-14014 October 1998 COLR for North Anna Power Station Unit 1 Cycle 14 Pattern Xy ML20155J6911998-10-0909 October 1998 Staff Response to Tasking Memorandum & Stakeholder Concerns ML20154H4001998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for North Anna Power Station,Units 1 & 2.With ML20151X8011998-09-10010 September 1998 Special Rept:On 980622,groundwater Level at Piezometer P-22 Was Again Noted to Be Above Max Water Level by 0.71 Feet. Increased Frequency of Piezometer Monitoring & Installed Addl Piezometers at Toe of Slope Along Southwest Section ML20151W4711998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for North Anna Power Station Units 1 & 2.With ML20237A4341998-07-31031 July 1998 Monthly Operating Repts for July 1998 for North Anna Power Station,Units 1 & 2 ML20236V1251998-07-14014 July 1998 ISI Summary Rept for Naps,Unit 2,1998 Refueling Outage Owners Rept of Isis ML20236K5531998-07-0707 July 1998 SER Accepting Request for Change in ISI Commitment on Protection Against Pipe Breaks Outside Containment ML20236M3381998-06-30030 June 1998 Monthly Operating Repts for June 1998 for North Anna Power Station,Units 1 & 2 ML20248M1011998-05-31031 May 1998 Monthly Operating Repts for May 1998 for North Anna Power Station,Units 1 & 2 ML20248C8831998-05-29029 May 1998 SER Accepting Alternatives Proposed by Licensee for Use of Code Case N-535,pursuant to 10CFRa(a)(3)(i) in ASME Section XI Inservice Insp Program ML20247K9281998-05-15015 May 1998 Special Rept:On 980428,letdown PCV Exhibited Slow Response When C RCP Was Started.Cause to Be Determined.Review of Operating Procedure Will Be Performed to Determine If Enhancements Are Necessary ML20216A8971998-05-0606 May 1998 Rev 0 to Cycle 13 Pattern Ud COLR for North Anna Unit 2 ML20247F4441998-04-30030 April 1998 Monthly Operating Repts for Apr 1998 for North Anna Power Station,Units 1 & 2 ML20217B5321998-04-20020 April 1998 Safety Evaluation Supporting Proposed Alternative to ASME Code for Surface Exam of Seal Welds on Threaded Caps for Plant Reactor Vessel Head Penetrations for part-length CRDMs ML20217H9611998-04-0707 April 1998 Special Rept:On 980216,groundwater Level at Piezometer P-22, Again Noted to Be Above Max Water Level by 0.41 Feet.Design Package for Installation of Addl Standpipe Piezometers at Toe of Slope Southeast Section,Developed ML20216B1891998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for North Anna Power Station,Units 1 & 2 ML20216E8801998-03-0606 March 1998 Safety Evaluation Authorizing Licensee Request for Relief from ASME Code Requirements,Paragraph IWA-2400(c) (Summer Edition W/Summer 1983 Addenda),For Upcoming Naps,Unit 1 Outage,Per 10CFR50.55a(a)(3)(ii) ML20216E2561998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for North Anna Power Station,Units 1 & 2 ML20199J6431998-02-0202 February 1998 Safety Evaluation Approving Request for Approval to Repair Flaws in Accordance W/Gl 90-05 for ASME Code Class 3 SW Piping for North Anna,Unit 1,as Submitted in ISI Relief Request NDE-46 on 971218 ML20202D5811998-01-31031 January 1998 Monthly Operating Repts for Jan 1998 for North Anna Power Station,Units 1 & 2 ML20198S7571998-01-15015 January 1998 Safety Evaluation Accepting Licensee Request for Approval to Repair Flaws IAW GL-90-05 for ASME Code Class 3 Svc Water Piping ML20198P1351997-12-31031 December 1997 Monthly Operating Repts for Dec 1997 for North Anna Power Station,Units 1 & 2 1999-09-08
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10 CFR 50.73 Virginia Electric and Power Company North Anna Power Station P. O. Box 402 Mineral, Virginia 23117 April 25,1994 U. S. Nuclear Regulatory Commission NAPS: MPW Document Control Desk Docket No. 50-339 Washington, D.C. 20555 License No. NPF-7
Dear Sirs:
Pursuant to North Anna Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Supplemental Licensee Event Report applicable to North Anna Unit 2.
Report No. 50-339/93-007-01 This Report has been reviewed by the Station Nuclear Safety and Operating Committee and will be forwarded to the Management Safety Review Committee for its review.
Very t uly ours, e ~
G. . ane Station Manager
Enclosure:
cc: U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W.
Suite 2900 Atlanta, Georgia 30323 R. D. McWhorter NRC Senior Resident inspector North Anna Power Station 94o5o3o273 940423
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1 IN#^uTNul"!ATREo"ETTJ"!O /uTs"A"WMME"!!s"d"0M' AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), Office Oh 4 (See reverse for required number of dgts/ characters for each block) MANAGEMENT AND BUDGET WASHINGTON.DC 20603.
FOCILITY NAME (1) DOCKET NUMHEH (2) PAGE(3)
North Anna Unit 2 05000339 1 cF 4 TITLE (4)
- HIGH HEAD SAFETY INJECTION FLOW BELOW TECHNICAL SPECIFICATION MINIMUM EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)
SEOU AL RE FACILrrY NAMES DOCKET NUMBER (S)
MONTH DAY YEAR YEAR MONTH DAY YEAR l
! 05000 DOCKET NUMBER (S) 14 007 01 04 25 94 10 93 93 05000 C7ERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 5:(Check one or more of the followina)(11)
MODE (9) 1 20.405(b) 50.73(a)(2)(iv) 73.71(b) 20.402(b) 20.405(a)(1)(i) 50.36(c)(1) 50.73(a)(2)(v) 73.71(c)
POWER Lgvyt 100 20.40s(axi)(ii) 50.36(c)(2) 50.73(a)(2)(vu) OrHER 20.405(ax1)(hi) X 50 m x2xo 50mx2xvmxA) n@a ow a%n 20.405(a)(1)(iv) 50.73(a)(2)(n 50.73(a)(2)(vm)(c) 20.405(a)(1)(v) 50.73(a)(2)(m) 50.73(a)(2)(s)
LICENSEE CONTACT FOR THIS LER (12) l NAME TELEPHONE NUMBER (inctuo Area Code)
Greg Kane, Station Manager (703) 894-2101 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) couSE SYSTEM COMPONENT MANUFACTURER R RTAB E CAUSE SYSTEM COMPONENT MANUFACTURER Af0 NPR 1
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, SUPPLEMENTAL REPORT EXPECTED (14) i l
YES EXPECTED MONTH DAY YEAR (t yes. cormiete EXPECTED SUBMISSION DATE) x NO S IN ABSTRACT (Limit 101400 spaces, i.e., apprOximately 15 Single-spaced typewritten lines) (16) l On October 14,1993, with Unit 2 in Mode 5 (Cold Shutdown), during High Head Safety injection (HHST) flow balance testing, the "as-found" cold leg branch line flow was found to be below the Technical Specifications (TS) minimum requirement. The sum of the branch line flows, excluding the highest flow rate, is required by T3 4.5.2.h to be greater than or equal to 359 gpm. However, the sum of the two l lowest measured branch flow rates was found at 356 gpm. The cold leg Safety injection throttle valves l
were adjusted so that sum of the two lowest flow rates was equal to 384 gpm.
4 On November 8,1993, concerns were identified about the flow balancing data due to instrument inaccuracies. All three charging pumps were twice declared inoperable, and TS 3.0.3 was entered. At ,
- 1402 hours0.0162 days <br />0.389 hours <br />0.00232 weeks <br />5.33461e-4 months <br /> on November 9,1993, seat injection flow was decreased to allow two charging pumps to meet
- the requirement of the TS, and TS 3.0.3 was exited. This event is reportable pursuant to 10 CFR 50.73 (a)(2)(i)(B) as a condition prohibited by Technical Specifications.
1 The primary suspected cause of the event is previously unaccounted for uncertainties in the Unit 2 HHSI flow balance measurements due tc, adverse system piping geometry's.
No significant safety consequences evolved as a result of this event because a previous analysis has
- shown that the existing HHSI branch flows are within the design basis limits. Therefore, the health and
- safety of the public were not affected.
I i
i NHG Form 366 @92)
c roeu asA gg-WW APPROVE 119-0104 8
LICENSEE EVENT REPORT (LER) $8n"gMy a ,U E EST HR OR R O ME S RE RD BUR M E H M A BA H TEXT CONTINUATION y#g^u'!. 'NUI R U 9, , s
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FACluTY NAME (1) DOCKET NUMBER m LER NUMBER (6) PAGE @
yg SEQUENTIAL REVISION North Anna Unit 2 05000 339 2 ' OF 4 93 -
007 -
01 TEXT (p more sp=:e = regned. vee eddeanal NRC Parm 364A s) (17) 1.0 Descriotion of the Event On October 14,1993, with Unit 2 in Mode 5 (Cold Shutdown), during High Head Safety injection (HHSI)
(Ells System Identifier BO) flow balance testing, the "as-found" cold leg branch line flow was found to be below the Technical Specifications (TS) minimum requirement. The sum of the branch line flows, excluding the highest flow rate, is required by TS 4.5.2.h to be greater than or equal to 359 gpm.
However, the sum of the two lowest measured branch flow rates was found at 356 gpm. The cold leg Safety injection throttle valves (Ells Component Identifier INV) were adjusted so that sum of the two lowest flow rates was equal to 384 gpm. ;
On November 8,1993, concems were identified about the flow balancing data due to instrument inaccuracies. These instruments inaccuracies were a result of the adverse system geometry's. All three charging pumps were declared inoperable at 0930 hours0.0108 days <br />0.258 hours <br />0.00154 weeks <br />3.53865e-4 months <br /> because they could not meet the requirements of TS 4.5.2.h and TS 3.0.3 was entered. Based on a preliminary Engineering calculation, the seal l injection flow rates were then adjusted to allow the HHSI flow balance to meet the TS requirement, and two of the charging pumps were declared operable at 1006 hours0.0116 days <br />0.279 hours <br />0.00166 weeks <br />3.82783e-4 months <br />. The computer HHSI System model showed that seal injection flow would have to be reduced more than predicted in the preliminary calculation to allow the HHSI flow balance to meet the TS requirements. At 1445 hours0.0167 days <br />0.401 hours <br />0.00239 weeks <br />5.498225e-4 months <br />, all three charging )
, pumps were again declared inoperable, and TS 3.0.3 was entered. NRC discretionary enforcement from l TS 4.5.2.h was requested, and a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> extension to restore two charging pumps to operable status was j received. At 1402 hours0.0162 days <br />0.389 hours <br />0.00232 weeks <br />5.33461e-4 months <br /> on November 9,1993, seal injection flow was further decreased to allow two I charging pumps to meet the requirement of the TS, and TS 3.0.3 was exited. This event is reportable pursuant to 10 CFR 50.73 (a)(2)(i)(B) as a condition prohibited by Technical Specifications.
2.0 Sionificant Safety Conseauences and imolications No significant safety consequences evolved as a result of this event because a previous analysis has l shown that the existing HHSI branch flows are within the design basis limits. Therefore, the health and l Safety of the public were not affected.
3.0 Cause of the Event 1
The Root Cause Evaluation (RCE) for this event has been completed. The primary cause is previously j unaccounted for uncertainties in the Unit 2 HHSi flow balance measurements due to adverse system I piping geometry. The HHSI system piping geometry contributes to a swirl flow to which the ultrasonic flow measurement equipment is extremely sensitive. A lack of understanding concoming the affect swirl flow has on flowmeter accuracy has, in the past, resulted in erroneous data.
The use of new technology (i.e. strap-on ultrasonic flowmeters) was based on an approved vendor's assessment that desired accuracy could be achieved. Available vendor information and vendor training of station personnel were relied upon to ensure proper application of the equipment. The vendor manual
! did not provide complete information conceming limitations of the ultrasonic flowmeters. It has been determined, depending on piping geometry that the flowmeters should be located as much as 100 pipe diameters downstream of any pipe fitting in order to remove the fluid swirl affect. In addition, multiple versus single beam transducer measurement techniques may be required to achieve the desired accuracy, it has also been determined, by in-house testing, that variation in the ultrasonic flowmeter transmit frequency has a large effect on the measured flow rate. The station procedure controlling the use of the flowmeters was generic and did not provide guidance on site specific problems which may be encountered.
NHG t orm 366A (542)
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I LICENSEE EVENT REPORT (LER) $$[!*sN"EN Re"8u'Ust '"o"d'E"o'RISnE $8PMEWS"REW RBUR TEXT CONTINUATION j#g^u$'N RE LT R CO M S , W ASH OC 50 1 0"aJMsf #i.L*1".%fs'28E"e"fei' "" "*' '
j rccurY NAME m DOCKET NUMBER G) LER NUMBER (8) PAGE (3)
, North Anna Unit 2 05000 339 3 OF 4 93 -
007 -
01 TEXT tu more space se reemM use edeem NRC Fem 364KW (17) i 3.0 Cause of the Event (continued) l In addition, the current Technical Specification requirements for acceptable HHSI flow balancing are extremely restrictive. After allowing for minor performance differences among individual HHSI pumps, and 1 the reactor coolant pump seal injection flow, there is a very narrow band of allowable flow rates. Achieving i flows with this narrow band requires very accurate flow measurement. Also, the restrictive flow band does not recognize the considerable margin to the safety analysis limits.
1 4.0 Immedinte Corrective Actions l The cold leg Safety injection throttle valves were adjusted so that the sum of the two lowest flow rates was j equal to 384 gpm.
- Loctite 290 Threadlocker@ was installed on the valve stem to yoke bushing to prevent valve stem movement.
i l The throttle valves were x-rayed and reviewed with the vendor for defects. It was determined that the i valves were intact.
i The sealinjection flow rates were adjusted to allow the HHSI flow balance to meet the TS requirement.
< NRC enforcement discretion from TS 4.5.2.h was requested and received.
1 5.0 Additional Corrective Actions An emergency TS change consistent with the NRC's enforcement discretion policy has been submitted.
! Further evaluation of the TS will be conducted to determine whether additional enhancements may be j warranted.
1 I 6.0 Actions to Prevent Recurrence
- 1 i Management has reviewed the recommendations of the completed root cause evaluation and determined I the following actions are necessary to prevent recurrence.
4
] The safety analysis will be evaluated for minimum acceptable emergency core cooling system flow rates to 1 justify a larger band of allowable flow rates.
{ A TS revision to Section 4.5.2.h has been submitted to the NRC to specify flow balance acceptance
, criteria values based on the results of the safety analysis evaluation rather than specific values. This allows 1 for fuel cycle and equipment specific considerations to be accounted for in the balancing test without
! requiring frequent TS changes.
The flow instruments for the cold leg branch lines will be replaced or supplemented with ;nstruments that measure flow more accurately.
6 j N% i Orm 366A @W) i
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"' APPftOVED 0480 NO. 3150 0104 l
. NRC FORM 366A pag;
- W"" "M "* " EXPIRES 5/31,95 LICENSEE EVENT REPORT (LER) eMl%fyE N RE" " PE EST ESgN E gP Y TH I I AMAT j
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FCCR.ITY NAME (1) 00CKEI NJW8E R @ LEA NUWRER(6) PAGE (3)
SEQUEWilAt REVISION YEAR North Anna Unit 2 05000 339 4 OF 4 93 -
007 -
01 TEXT m more space a rapnee. use seasones emc perm suA's) (17)
If continued use of strap-on ultrasonic flowmeters is anticipated for Safety Related apolications, engineering training will be administered for their use.
The station controlling procedure for strap-on ultrasonic flowmeters will be updated to incorporate findings from the RCE with regard to proper use and the limitations of this technology.
An Operating Experience entry will be made to ale,t the industry on the results of the root cause evaluation.
7.0 Similar Eventi LER 50-339/90-008-00 documents the sum of the two lowest branch flows being less than the TS minimum requirement (Unit 2). The cause of this event was instrument uncertainties and improper i methods for measuring flow.
LER 50-339/92-010-00 documents the sum of the two lowest branch flows being below the TS minimum requirement (Unit 2). The cause of this event was valve mispositioning.
LER 50-338/93 009-00 documents the sum of the two lowest branch flow lines being below the TS minimum requirement (Unit 1). The cause of this event was too narrow of a TS allowable flow rate to be consistently met with instrumentation uncertainties.
8.0 AMitbr.pl InformatiQD Unit 1 was at 100% power (Mode 1) and was not directly affected by this event. Corrective actions for Unit 2 will also be performed on Unit 1 as applicable.
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