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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
[Table view] |
Text
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{1 lf ., j :I VIRGINI A ELECTRIC AND PC'WER COMPANY 10 CFR 50.73. ]
l.Y ' NORTH ANN A POWER ST ATION
. 4 k1 P. O. BOX 402
, MINER AL, VIRGINI A 23117 E
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jL January 11, 1990 l I' - U. S. Nuclear Regulatory Commission Serial No. ' N-89-025 Attention: Document Control Desk NAPS /DEQ:deq .
Washington, D.C. 20555 Docket No. 50-338 License No. NPF-4 "
Dear Sirs:
! .. ? i . .
~ The Virginia Electric and Power Company hereby submits the following Licensee Event Report
- applicable to Nonh Anna Unit 1. - a Report No. LER 89-018-00 This Repon has been reviewed by the Station Nuclear and Operating Committee and will be
' forwarded to Safety Evaluation and Control for their review.
Very Truly Yours, E. Kane Station Manager 1
Enclosure:
- cx:: U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W.
Suite 2900 Atlanta, Georgia 30323 Mr. J. L. Caldwell l NRC Senior Resident Inspector j f, North Anna Power Station i 9001170347 900111 9 PDR ADOCK 0500 S e 1
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- f. FORMSEE, U.S. EUCLE A3 2 EIULATGY COMMISSION d.PPIOVED OMS NO.31604104 EXPIMS 4/30/92
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UCENSEE EVENT REPORT (LERI ESTIMATED BURDEN FER RESPONSE TO COMPLY WTH THl$
CO M NTs'Uo?Ro'i!*O f?"Ro"EN NT7dAYE t T* ""' E REC %
ULATORY M i SiON W ASHINGT N 66 AND 0
, THE PAPERWORK REDUCTION PROJECT (31600104L OFFICE OF MANAGEMENT AND 9UDOE T.WA$HINCTON.DC 20603.
PACILtTV NAMai til DOCEET Ntm00ER (25 FADE G
~ NORTH ANNA POWER STATION, UNITS 1 AND 2 0 l5 l 0 l 0 l 0 l 3 l 318 1loFl014 E' f thE tal
-UNCERTAINTY ASSOCIATED WITH HARSH ENVIRONMENT BELOW ESF TRANSMITTER RANGE EVENT DATE tll LER NUMBER (6) REPORT DATE (?) OTHER F ACILITIES INVOLVED tel MONTH DAV YEAR YEAR 8
, '7[ MONTH DAY YEAR ' ACILIT v h AMES DOCKET NUM6Ent$1 NORTH ANNA. UNTT 2 0l5]Ol0l0 l313 19
~ ~
lI2 If9 '8 19 8 l9 0l1 l8 0 l0 0 l1 1l1 9 l0 0 1 5 1 0 10 1 0 t l l THis REPORT 88 $USMITTED PURSUANT TO THE RkOUIREMENTS OF 10 CFR I (Cneca one e, niere e,,ne ,eisewisief (11)
' OPERATING MODE m - r3 20 402861 20 40tist 90 734elGHeel 73.71(b)
R 20.405teH1Hil 40.36teH1) 80.73teH2 Hut 73.71ts)
(10i 01010 30 ansion1Hul somenal 1 so 73isH2Hval
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30 4084eH1Hlel . 50.736eH211dl GC.73teH2HvuiHB) 30 406tell1Hv! S0.73teH2Hahl to 73teH211al LICEN$EE CONT ACT FOR THl3 LER 412) ,
NiME TELEPFONE NVM8tR ARE A CODE C. E. Kane, Station Manager 7 l0 l3 819 l 4 l -12 l 1 l 0l1 COMPLETE ONE LINE FOR E ACH COMPONENT F AILURE DESCRitED IN TH18 REPORT (13)
R L MA A PORTA LE Clust SYSTEM , COMPONENT "'N[g AC. O PR S CAU$t $Y ST E M COMPONENT AC-pp g 1 I I l i I I I I I f. I i 1 l.
I I I I I I I I I I I I I I IUPPLEMENT AL REPORT E xPECTED (141 MONTH DAY YEAR l i SUBMi&SION YE$ (19 yes, earnete,e LXPECTED SuGMISSION DATE) NO l l l ,
A T.. AC , ,-,, ,e ,. .e-e, a e . see,e_e.e. ,,,,e e .e-e , ee .. .ne., t,.. !
L At 1430 hours0.0166 days <br />0.397 hours <br />0.00236 weeks <br />5.44115e-4 months <br /> on December 19, 1989, with Unit 1 in cold shutdown (Mode 1 5) and Unit 2 at 100 percent power, engineering personnel determined that the three Pressurizer (Pzr) Pressure - Safety Injection (SI) instrumentation channels may not have adequate margin between the SI actuation setpoint and i the bottom of the instrument span to accomodate the errors associated with a L harsh containment environment. As a result, the Pzr low pressure SI actuation may not occur because of the potential for the transmitter to saturate below its g calibration span. Since all three channels could be affected if a harsh l containment condition exists, this event is reportable pursuant to 10CFR50.73(a)(2)(vii).
l l Failure to accomodate the errors associated with a harsh containment L environment following a small steam line bitak (SLB) inside containment is a
, result of -assuming a more conservative approach with respect to the l L environmental qualification assumptions for the transmitters. An l
engineering evaluation was performed to verify acceptable performance with the existing conditions. License Amendments wili be requested to incorporate j the respective analyses which justifies climination of the low pressure SI for ;
small SLBs into the licensing bases. I This event posed minimal safety implications because the existing SBLOCA and the existing small SLB inside containment evaluations remained valid. The health and safety of the general public were not affected at any time during this event.
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- E3ULAT(MY COMH98604 g 7e 1- 1 dCENSEE EVENT REPORT (LER) TEXT CONTINUATION nenoveo ous No mo+os EXPtRES: $/3U38 '
PActLITY esee86 (H - DOCKti NUed8FR (23 LER NUMSIR (6) PAGE13)> W
< v5aa "$7.lk ' My*.'N I iNORTH ANNA POWER' STATION,' UNITS 1 AND'2 0'l5 l0 j o l0 l 3l3 l8 -
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0 'l0 -0l2 0F 0~j4 sexi tu mee =ar e au. no un ww nc remo .nu mm 1 1.0 _ Descriotion 'of the - Event ;j At 1430- hours 'on December 19,-19'89,- with Unit l' in ' cold shutdown (Mode )
- 5)- and Unit { 2. at c 100 a percent power, engineering personnel determined that j
, the three Pressurizer (Pzr) Pressure - Safety ~ 1njection '(SI) (Ells. System i Identifieri BQ)- instrumentation channels -(Ells System Identifier ' JE, I s LComponent Identifier CHA) may not have adequate margin between the SI l' actuation setpoint and . the-' bottom of the instrument ' span to accomodate the i
. crrors associated with' a harsh containment'. environment. As a result, the Pzr. -l low pressure St actuation may not ~ occur beettuse of the potential for the .
. transmitter - to saturate below its calibration span. Since all three channels could ' be . affected :if a ; harsh containment condition exists, this event is reportable pursuant to 10CFR50.73(a)(2)(v). 1 The calibration span of the Pzr pressure SI instrumentation is between 1700 and. 2500 psig. The calibration procedure for the three Pzr low pressure 7 SI- instrument channels. specifies a setting of '1765 psig. This is consistent with . the ' Technical . Specifications which set forth a value of greater than or equal to 1765: psig with an allowable of greater than or equal to 1755 psig. The.
~ instrument ' loop ~ uncertainty is 157.7: psig (based on the limiting containment g
environmental conditions expected prior to SI actuation : following a steam
, line break ' inside containment equivalent to the UFSAR L credible steam line break). .The uncertainty of 157.7 psig subtracted from the 1765 psig setpoint
~o f the -instrument channels falls below the instrument span of 1700 psig.
Consequently, an SI may not be initiated, if a harsh containment condition ,
exists.
' Additionally, the minimum Si actuation setting of 1755 psig specified by the Technical Specifications rainus the uncertainty of 157.7 psig is equal to a value of 1597.3 psig. The safety analysis limit for the low Pzr pressure SI is 1595 psig. Since 1597.3 psig is above the safety analysis limit, full compliance with the Technical Specifications has been achieved and the safety analysis has been verified to adequately reflect the instrument uncertainties.
However, as discussed above, the current calibration span for the transmitters may not be wide enough to accomodate these uncertainties.
2.0 Significant S afety Consequences and Imolientions The small break Loss of Coolant Accident (SBLOCA) and the small steam line break (SLB) are the only two accident analyses in the current licensing li basis which rely on the low Pzr pressure SI and for which a harsh
- . containment environment would exist.
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, # :.$ UCENSEE EVENT REPORT (LER) TEXT CONTINUATION - umovro ows No. siso-oion - s; r EXPIRES: 8/T1/IB 4' , ;
PACILITY f6ft9m H) DOCSET NUMBER (23 LER NUMOtR 161 PAGE131 E.I dI," " D 'NuaN s
, NORT11 ANNA' POWER' STATION, UNITS 1 AND 2 - o l5 l0 l0 l0 l3 l3 l8 8l9 -
0 l 1l8 -
0 l0 0 l3 0F 0 'l 4 tai ta ==. . w. =w imie r assw Hn 4 Siculticant safety- Conscauences and Imnlications Cont'dc 2.0 u
, ThisL event posed min'i mal safety implications because results of 'a safety-F > evaluation; for the . Pzr low pressure Si channels ~ has determined the
, .following: .
. 1. For the SBLOCA it' has been concluded that a SI is initiated before the -
I containment = environment becomes harsh, and therefore. - the existing {
SBLOCA evaluation remains valid. 1
- 2. For. the small SLB inside containment, it was determined that a SI would X be initiated by a high : containment pressure at or before . the assumed .
SI . from, pressurizer low pressure. Additionally, even if no SI were to occur for any size SLB up to the equivalent of the credible SLB, the existing small , SLB- inside containment evaluation remains valid.
- ' ' The . health and safety ' of ' the general pub!!c were not affected at any
..l E time ' during this event.~
3.0 Cause of the Event Failure ; to accomodate the errors associated with a harsh containment !
> environment . is a result of assuming a more conservative approach - for the environmental ' qualification assumptions of the transmitters, than was used i to establish the setpoint' sed calibration span.
4.0 Immediate correctivc_ Action As an immediate corrective action, an engineering evaluation was performed to verify acceptable performance with the existing conditions.
5.0 Additional ' Corrective Action License Amendments will be requested to incorporate the respective analyses which justifies climination of the low pressure SI for small SLDs into the licensing bases. Appropriate changes will be made to the UFSAR as part of the License amendments.
Additionally, the other Engineered Safety Features (ESF) and Reactor Protection System (RPS) instrumentation setpoints stated in the Technical Specifications will be verified to assure that uncertainties have been adequately accounted for. This includes uncertainties associated with a harsh environment, i-g ,
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tents: ews FAcetlTT teAtel (18 DOCkti Nuhetth L3) LtR Nunetth tel PA06 (36
[- YEAR "" NIn"' '
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4
,gorTH ANNA POVER STATION. UNITS 1 AND 7 0 l6 l0 l0 l0 l 3l3 lg gl 9 -
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olo ol4 oF 0 l4 TEXT L aise ausse 4 messer, eser aesteepest NRC form W W (17)
' 6.0 Actions to Prevent Recurrence To prevent recurrence of similar events, the safety analysis limits for the ESF and RPS instrumentation stated in the Technical Specifications were verified to ' be within the range of the instrumentation.
7.0 Similar Events Previous events involving environmental qualification issues have t
occurred at North Anna Unit 1 on August 19,1987 (LER N1/87 018 00) and i September 11,1987 (LER N1/87 02100 and its supplement).
L h H.0 Additional Information
! f L lt has beet. recognized that the potential climination of the low '
pressure SI for small SLBs inside containment represents a change to the facility. Evaluation of this change in accordance with 10 CFR 50.59 has determined that an unreviewed safety question exists. However, the safety consequences are minimal, as described in section 2.0, and continued operation is justified. License Amendments will be requested to incorporate the respective analyses which justifies climination of the low pressure Si for small SLBs into the licensing bases. Appropriate changes will be made to the UFSAR as part of the License Amendments, l-l l-l NI POIM 346a 'c.5. CNa 19F8- 51b Afe' CN PO
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