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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr ML17229A7381998-05-21021 May 1998 LER 98-006-00:on 980421,missed EDG Fuel Oil Sample Surveillance Was Noted.Caused by Personnel Error.Revised Fuel Oil Sampling Service Purchase Order & Revised Site procedure.W/980521 Ltr ML17229A7011998-04-27027 April 1998 LER 98-003-00:on 980326,discovered Containment Pressure Instrumentation Design Single Failure Vulnerability.Caused by Inadequate Design by Personnel Error.Removed RPS & ESFAS Containment Pressure Bypass Keys immediately.W/980427 Ltr ML17229A6761998-04-0202 April 1998 LER 98-005-00:on 980305,identified Two Conditions That Were Outside App R Design Bases.Caused by Design Oversight During Development of Original App R Safe SD Design.Established 30 Minute Roving Fire Watches & Provided training.W/980402 Ltr ML17229A6731998-03-26026 March 1998 LER 98-002-00:on 980224,radiation Monitor Surveillance Inadequacies Led to Operating of Facility Prohibited by Tss. Caused by Congnitive Personnel Error.Permanent Procedure Changes Were implemented.W/980326 Ltr ML17229A6551998-03-0505 March 1998 LER 98-001-00:on 980206,high/low Pressure Shutdown Cooling Interface Was Noted Outside App R Design Bases.Caused by Personnel Error.Addl Guidance Was Provided to Engineering Dept personnel.W/980305 Ltr ML17229A6281998-02-19019 February 1998 LER 98-004-00:on 980121,emergency Lighting Outside App R Design Bases Occurred.Caused by Congnitive Personnel Error During Translation of App R Section Iii.Procedures Onop 1 & 2 ONP-100.01 Were Issued for Use on 980206.W/980219 Ltr ML17229A6211998-02-0909 February 1998 LER 98-003-00:on 980110,manual Rt Due to DEH Leak at Turbine Test Block Was Noted.Caused by o-ring Extrusion.Shortened Bolts by About 0.125 & Reinstalled at Correct Torque values.W/980209 Ltr ML17229A6191998-02-0404 February 1998 LER 98-002-00:on 980105,CIS Bistable in Bypass Resulted in Condition Prohibited by Tss.Caused by Personnel Error. Radiation Monitor Was Restored to service.W/980204 Ltr ML17229A6161998-02-0303 February 1998 LER 98-001-00:on 980104,inadvertent RPS Actuation Occurred Due to Personnel Error.Caused by Procedural Inadequacies & Inadequate self-checking by Licensed Utility Personnel. Placards Have Been Placed in CRs.W/980203 Ltr ML17229A6051998-01-27027 January 1998 LER 97-010-01:on 971027,inadvertent Core Alteration Prohibited by TSs Were Noted Due to Stuck Cea.Caused by Personnel Error.Cea #24 Was Dislodged & Transferred to Spent Pool for insp.W/980127 Ltr ML17229A5501997-12-0505 December 1997 LER 97-008-00:on 971107,inadequate CR Ventilation Surveillance Resulted in Condition Prohibited by Ts.Caused by non-cognitive Personnel Error.Operating Procedure 2-1900050 Was revised.W/971205 Ltr ML17309A9091997-12-0202 December 1997 LER 97-011-00:on 971102,non-conservative RAS Set Point Resulted in Operation Prohibited by Ts.Caused by Inadequate Set Point & Instrument Loop Scaling Process.Revised ESFAS Functional Tp W/Proper Set point.W/971202 Ltr ML17229A5391997-11-26026 November 1997 LER 97-010-00:on 971027,inadvertant Core Alteration Prohibited by TS Occurred.Caused by CEA Failure to Detach from Ugs.Safety Evaluation Was Performed & Procedural Rev Made to Continue Upper Guide Structure move.W/971126 Ltr ML17229A5151997-11-0707 November 1997 LER 97-007-00:on 971008,inoperable Containment Cooling Fan Resulted in Operation of Facility Outside Design Basis. Caused by non-cognitive Personnel Error.Ccs Operation Was Revised & Issued on 971013.W/971107 Ltr ML17229A4991997-10-17017 October 1997 LER 97-009-00:on 970917,inoperable PORV Block Valve Resulted in Operation Prohibited by Tech Specs Occurred.Caused by Plant GL 89-10 Program Plan to Review Plant Manager Action Item Sys.Porv Block Valve V-1403 restored.W/971017 Ltr ML17309A9011997-08-27027 August 1997 LER 97-008-00:on 970728,mechanical Fire Penetrations Were Inoperable & Outside App R Design Bases.Caused by Seal Mfg Not Providing Formal Documentation for Installed Seals. Modified Inoperable Fire penetrations.W/970827 Ltr ML17229A4311997-07-29029 July 1997 LER 97-006-00:on 970630,discovered Inadequate Testing of Engineered Safety Features Subgroup Relays.Caused by Inadequacy in Implementing TS Requirements in Surveillance Procedures.Revised Surveillance procedures.W/970729 Ltr ML17229A4241997-07-25025 July 1997 LER 97-005-00:on 970625,discovered That Hot Shutdown Control Panel Shutdown Cooling Flow indicator,FI-3306 Inoperable. Caused by Weakness in Work Order & Procedure Used to Repair FI-3306.Section Meeting W/I&C Planners held.W/970725 Ltr ML17229A3971997-07-11011 July 1997 LER 97-004-00:on 970611,discovered Incorrect Original Cable Tray Fire Stop Assembly Installation Was Outside App R Design Basis.Caused by Personnel Error.Hourly Fire Watch Patrols Will Be posted.W/970711 Ltr ML17229A3871997-06-19019 June 1997 LER 97-003-00:on 970521,determined Required Post Maint Open Stroke Test for Valve V3245,2B2 SIT Discharge Check Valve, Had Not Been Performed.Caused by Personnel Error.Procedure revised.W/970619 Ltr ML17229A3841997-06-17017 June 1997 LER 97-002-00:on 970518,containment Sump Debris Screen Was Not IAW Design Due to Gaps in Screen Encl.Performed SER to Document Containment Sump Design requirements.W/970617 Ltr ML17229A3751997-06-0202 June 1997 LER 97-006-00:on 970501,operation Was Prohibited by TS Due to Inadequately Tested Degraded Voltage Sys.Revised Unit 1 ESFAS Surveillance Test procedure.W/970602 Ltr ML17229A3611997-05-29029 May 1997 LER 97-007-00:on 970502,reactor Coolant Pump Oil Collection Sys Was Outside App R Design Bases.Identified Leak Sites Were Repaired & Mods to RCP Oil Collection Sys to Capture Any Future Leakage from areas.W/970529 Ltr ML17229A3491997-05-21021 May 1997 LER 97-001-00:on 970423,containment Isolation Actuation Occurred.Caused by Increased Radiation Levels During Removal of Upper Guide Structure.Proper Actuation of Containment Isolation Components Was verified.W/970521 Ltr ML17229A3441997-05-13013 May 1997 LER 97-005-00:on 970419,reactor Was Shutdown Due to Reactor Coolant Pressure Boundary Leakage.Hot Cracking Was Caused by Weld Contamination.Repairs to RCPB Were Completed & 1A SDC Train Was Restored to Svc ML17229A3141997-04-30030 April 1997 LER 97-004-00:on 970402,refueling Machine Was Operating in Manner Prohibited by TS Due to Original Design of Refueling Machine Bypass Feature Conflicting W/Ts Requirements. Eliminated Overload Cut Off Limit bypass.W/970430 Ltr ML17229A2951997-03-31031 March 1997 LER 97-003-00:on 970304,automatic Rt Resulted from Loss of Electrical Power to 1A2 Rc Pump.Rcp Breaker Was Replaced & Pump Was Returned to svc.W/970331 Ltr ML17229A2721997-03-21021 March 1997 LER 97-002-00:on 970221,operation in Excess of Max Rated Thermal Power Occurred Due to Digital Data Processing Sys (Ddps) Calorimetric Error.Verified Acceptable Performance of Ddps Functions & Reviewed Software mods.W/970321 Ltr 1999-07-06
[Table view] Category:RO)
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr ML17229A7381998-05-21021 May 1998 LER 98-006-00:on 980421,missed EDG Fuel Oil Sample Surveillance Was Noted.Caused by Personnel Error.Revised Fuel Oil Sampling Service Purchase Order & Revised Site procedure.W/980521 Ltr ML17229A7011998-04-27027 April 1998 LER 98-003-00:on 980326,discovered Containment Pressure Instrumentation Design Single Failure Vulnerability.Caused by Inadequate Design by Personnel Error.Removed RPS & ESFAS Containment Pressure Bypass Keys immediately.W/980427 Ltr ML17229A6761998-04-0202 April 1998 LER 98-005-00:on 980305,identified Two Conditions That Were Outside App R Design Bases.Caused by Design Oversight During Development of Original App R Safe SD Design.Established 30 Minute Roving Fire Watches & Provided training.W/980402 Ltr ML17229A6731998-03-26026 March 1998 LER 98-002-00:on 980224,radiation Monitor Surveillance Inadequacies Led to Operating of Facility Prohibited by Tss. Caused by Congnitive Personnel Error.Permanent Procedure Changes Were implemented.W/980326 Ltr ML17229A6551998-03-0505 March 1998 LER 98-001-00:on 980206,high/low Pressure Shutdown Cooling Interface Was Noted Outside App R Design Bases.Caused by Personnel Error.Addl Guidance Was Provided to Engineering Dept personnel.W/980305 Ltr ML17229A6281998-02-19019 February 1998 LER 98-004-00:on 980121,emergency Lighting Outside App R Design Bases Occurred.Caused by Congnitive Personnel Error During Translation of App R Section Iii.Procedures Onop 1 & 2 ONP-100.01 Were Issued for Use on 980206.W/980219 Ltr ML17229A6211998-02-0909 February 1998 LER 98-003-00:on 980110,manual Rt Due to DEH Leak at Turbine Test Block Was Noted.Caused by o-ring Extrusion.Shortened Bolts by About 0.125 & Reinstalled at Correct Torque values.W/980209 Ltr ML17229A6191998-02-0404 February 1998 LER 98-002-00:on 980105,CIS Bistable in Bypass Resulted in Condition Prohibited by Tss.Caused by Personnel Error. Radiation Monitor Was Restored to service.W/980204 Ltr ML17229A6161998-02-0303 February 1998 LER 98-001-00:on 980104,inadvertent RPS Actuation Occurred Due to Personnel Error.Caused by Procedural Inadequacies & Inadequate self-checking by Licensed Utility Personnel. Placards Have Been Placed in CRs.W/980203 Ltr ML17229A6051998-01-27027 January 1998 LER 97-010-01:on 971027,inadvertent Core Alteration Prohibited by TSs Were Noted Due to Stuck Cea.Caused by Personnel Error.Cea #24 Was Dislodged & Transferred to Spent Pool for insp.W/980127 Ltr ML17229A5501997-12-0505 December 1997 LER 97-008-00:on 971107,inadequate CR Ventilation Surveillance Resulted in Condition Prohibited by Ts.Caused by non-cognitive Personnel Error.Operating Procedure 2-1900050 Was revised.W/971205 Ltr ML17309A9091997-12-0202 December 1997 LER 97-011-00:on 971102,non-conservative RAS Set Point Resulted in Operation Prohibited by Ts.Caused by Inadequate Set Point & Instrument Loop Scaling Process.Revised ESFAS Functional Tp W/Proper Set point.W/971202 Ltr ML17229A5391997-11-26026 November 1997 LER 97-010-00:on 971027,inadvertant Core Alteration Prohibited by TS Occurred.Caused by CEA Failure to Detach from Ugs.Safety Evaluation Was Performed & Procedural Rev Made to Continue Upper Guide Structure move.W/971126 Ltr ML17229A5151997-11-0707 November 1997 LER 97-007-00:on 971008,inoperable Containment Cooling Fan Resulted in Operation of Facility Outside Design Basis. Caused by non-cognitive Personnel Error.Ccs Operation Was Revised & Issued on 971013.W/971107 Ltr ML17229A4991997-10-17017 October 1997 LER 97-009-00:on 970917,inoperable PORV Block Valve Resulted in Operation Prohibited by Tech Specs Occurred.Caused by Plant GL 89-10 Program Plan to Review Plant Manager Action Item Sys.Porv Block Valve V-1403 restored.W/971017 Ltr ML17309A9011997-08-27027 August 1997 LER 97-008-00:on 970728,mechanical Fire Penetrations Were Inoperable & Outside App R Design Bases.Caused by Seal Mfg Not Providing Formal Documentation for Installed Seals. Modified Inoperable Fire penetrations.W/970827 Ltr ML17229A4311997-07-29029 July 1997 LER 97-006-00:on 970630,discovered Inadequate Testing of Engineered Safety Features Subgroup Relays.Caused by Inadequacy in Implementing TS Requirements in Surveillance Procedures.Revised Surveillance procedures.W/970729 Ltr ML17229A4241997-07-25025 July 1997 LER 97-005-00:on 970625,discovered That Hot Shutdown Control Panel Shutdown Cooling Flow indicator,FI-3306 Inoperable. Caused by Weakness in Work Order & Procedure Used to Repair FI-3306.Section Meeting W/I&C Planners held.W/970725 Ltr ML17229A3971997-07-11011 July 1997 LER 97-004-00:on 970611,discovered Incorrect Original Cable Tray Fire Stop Assembly Installation Was Outside App R Design Basis.Caused by Personnel Error.Hourly Fire Watch Patrols Will Be posted.W/970711 Ltr ML17229A3871997-06-19019 June 1997 LER 97-003-00:on 970521,determined Required Post Maint Open Stroke Test for Valve V3245,2B2 SIT Discharge Check Valve, Had Not Been Performed.Caused by Personnel Error.Procedure revised.W/970619 Ltr ML17229A3841997-06-17017 June 1997 LER 97-002-00:on 970518,containment Sump Debris Screen Was Not IAW Design Due to Gaps in Screen Encl.Performed SER to Document Containment Sump Design requirements.W/970617 Ltr ML17229A3751997-06-0202 June 1997 LER 97-006-00:on 970501,operation Was Prohibited by TS Due to Inadequately Tested Degraded Voltage Sys.Revised Unit 1 ESFAS Surveillance Test procedure.W/970602 Ltr ML17229A3611997-05-29029 May 1997 LER 97-007-00:on 970502,reactor Coolant Pump Oil Collection Sys Was Outside App R Design Bases.Identified Leak Sites Were Repaired & Mods to RCP Oil Collection Sys to Capture Any Future Leakage from areas.W/970529 Ltr ML17229A3491997-05-21021 May 1997 LER 97-001-00:on 970423,containment Isolation Actuation Occurred.Caused by Increased Radiation Levels During Removal of Upper Guide Structure.Proper Actuation of Containment Isolation Components Was verified.W/970521 Ltr ML17229A3441997-05-13013 May 1997 LER 97-005-00:on 970419,reactor Was Shutdown Due to Reactor Coolant Pressure Boundary Leakage.Hot Cracking Was Caused by Weld Contamination.Repairs to RCPB Were Completed & 1A SDC Train Was Restored to Svc ML17229A3141997-04-30030 April 1997 LER 97-004-00:on 970402,refueling Machine Was Operating in Manner Prohibited by TS Due to Original Design of Refueling Machine Bypass Feature Conflicting W/Ts Requirements. Eliminated Overload Cut Off Limit bypass.W/970430 Ltr ML17229A2951997-03-31031 March 1997 LER 97-003-00:on 970304,automatic Rt Resulted from Loss of Electrical Power to 1A2 Rc Pump.Rcp Breaker Was Replaced & Pump Was Returned to svc.W/970331 Ltr ML17229A2721997-03-21021 March 1997 LER 97-002-00:on 970221,operation in Excess of Max Rated Thermal Power Occurred Due to Digital Data Processing Sys (Ddps) Calorimetric Error.Verified Acceptable Performance of Ddps Functions & Reviewed Software mods.W/970321 Ltr 1999-07-06
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4951999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for St Lucie,Units 1 & 2.With 991014 Ltr ML17241A4741999-08-31031 August 1999 Rev 1 to PCM 99016, St Lucie Unit 1,Cycle 16 Colr. ML17241A4591999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for St Lucie,Units 1 & 2.With 990913 Ltr ML17241A4301999-07-31031 July 1999 Monthly Operating Repts for Jul 1999 for St Lucie Units 1 & 2.With 990805 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A4091999-06-30030 June 1999 Monthly Operating Repts for June 1999 for St Lucie,Units 1 & 2.With 990712 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17355A3681999-06-30030 June 1999 Revised Update to Topical QA Rept, Dtd June 1999 ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3631999-05-31031 May 1999 Monthly Operating Repts for May 1999 for St Lucie Units 1 & 2.With 990610 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17241A3331999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for St Lucie,Units 1 & 2.With 990517 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0841999-04-0707 April 1999 Rev 2 to PSL-ENG-SEMS-98-102, Engineering Evaluation of ECCS Suction Lines. ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0961999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for St Lucie,Units 1 & 2.With 990408 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229B0461999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for St Lucie,Units 1 & 2.With 990310 Ltr ML17229B0051999-01-31031 January 1999 Monthly Operating Repts for Jan 1999 for St Lucie,Units 1 & 2.With 990211 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9961999-01-14014 January 1999 SG Tube Inservice Insp Special Rept. ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9831998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for St Lucie,Units 1 & 2.With 990111 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17241A3581998-12-0909 December 1998 Changes,Tests & Experiments Made as Allowed by 10CFR50.59 for Period of 970526-981209. ML17229A9421998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for St Lucie,Units 1 & 2.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17241A4931998-11-0101 November 1998 Statement of Account for Period of 981101-990930 for Suntrust Bank,As Trustee for Florida Municipal Power Agency Nuclear Decommissioning Trust (St Lucie Project). ML17229A9051998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for St Lucie,Units 1 & 2.With 981110 Ltr ML17229A8871998-10-19019 October 1998 Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1 Which Was Machined with Improper Length.C/A Includes Insp Equipment That Will 100% Identify Short Length ML17229A8781998-10-19019 October 1998 Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1,which Was Machined with Improper Length.Insp Equipment That Will 100% Identify Short Length ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8721998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for St Lucie Units 1 & 2.With 981009 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8611998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for St Lucie,Units 1 & 2.With 980911 Ltr ML18066A2771998-08-13013 August 1998 Part 21 Rept Re Deficiency in CE Current Screening Methodology for Determining Limiting Fuel Assembly for Detailed PWR thermal-hydraulic Sa.Evaluations Were Performed for Affected Plants to Determine Effect of Deficiency ML17229A8481998-08-0707 August 1998 Rev 1 to PSL-ENG-SEFJ-98-013, St Lucie Unit 2,Cycle 10 Colr. ML17229A9461998-08-0707 August 1998 Rev 0 to PCM 98016, St Lucie Unit 2,Cycle 11 Colr. ML17229A8301998-07-31031 July 1998 Monthly Operating Repts for July 1998 for St Lucie,Units 1 & 2.W/980814 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7981998-06-30030 June 1998 Monthly Operating Repts for June 1998 for St Lucie,Units 1 & 2.W/980713 Ltr ML17229A7701998-05-31031 May 1998 Monthly Operating Repts for May 1998 for St Lucie,Units 1 & 2.W/980612 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr 1999-09-30
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CATEGORY 3y
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REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9904090149 DOC.DATE: 99/04/07 NOTARIZED: NO DOCKET FACIL:50-389 St. Lucie Plant, Unit 2, Florida Power S Light Co. 05000389 AUTH.N9ME . AUTHOR AFFILIATION MADDEN,G.R. Florida Power 6 Light Co.
STALL,J.A. Florida Power &: Light Co.
RECIP.NAME RECIPIENT AFFILIATION
SUBJECT:
LER 99-002-00:on 990311,SG ECT error causes operation with condition prohibited by TS.Caused by deficiencies in data analysis 'guideline instructions. Licensee will change data analysis guidelines for lead analysts. With 990407 ltr.
DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:
TITLE 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:
RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-3 PD 1 1 GLEAVES,W 1 1 INTERNAL: ACRS 1 1 AEOD SPD/RAB 2 2 AEOD/SPD/RRAB '
1 LE CENT 1 1 NRR/DRCH/HOHB 1 1 NRR DRCH HQMB 1 1 NRR/DRPM/PECB 1 1, NRR/DSSA/SPLB 1 1 RES/DET/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: L ST LOBBY WARD 1 1 LMITCO MARSHALL 1 1 NOAC POOREiW 1 D
1 NOAC QUEENER,DS 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 0
N NOTE TO ALL nRIDS>i RECIPIENTS PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPZES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 19 ENCL 19
Florida Power & Light Company. 6351 S. Ocean Orive, Jensen Beach, FL 34957 April 7, 1999
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FPt L-99-86 10 CFR $ 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Re: St. Lucie Unit 2 Docket No. 50-389 Reportable Event: 1999-002-00 Date of Event: March 11, 1999 SG ECT Error Causes Operation with a Condition Prohibited b Technical S eciftcations The attached Licensee Event Report 1999-002 is being submitted pursuant to the requirements of 10 CFR $ 50.73 to provide notification of the subject event.
Very truly yours, J. A. Stall Site Vice President St. Lucie Nuclear Plant JAS/EJW/GRM Attachment cc: Regional Administrator, USNRC Region II Senior Resident Inspector, USNRC, St. Lucie Nuclear Plant 9904090149 990407 PDR ADQCK 05000389 S PDR an FPL Group company
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150.0104 EXPIRES 06/30/2001 (6-1996) j Estimated burden per response to comply with lhis mandatory information collection request: 50 hrs. Reported lessons loomed are incorporated Into lhe licensing process and fed back to Industry. Fonrrard comments regarding LICENSEE EVENT REPORT (LER) burden estimate lo Ihe Records Management Bmnch (TA F33), U.S. Nuckrar Regulatory Commission, Washington, )3C 205554001 and to the Paperwrxk
~
Reduction Proioct (31500104j, Office of Management and Budget, (See reverse for required number of Washington, Dc 20503. If an fnfonnalion collection does not dispbry a currently valid OMB control number, the NRC may nol conduct or sponsor, digits/characters for each block) and a person is not required to respond lo, Ihe Information collection.
FACILITY NAME (1 I DOCKET NUMBER (2) PAGE (3)
St. Lucie Unit 2 05000389 Page 1 of 6 TITLE (4)
SG ECT Error Causes Operation with a Condition Prohibited by Technical Specifications EVENT DATE (5 LER NUMBER 6l REPORT DATE (7) OTHER FACILITIES INVOLVED (Bl SEQUENTIAL REVISION FACILITYNAME OOCKET NUMBER MONTH OAY YEAR NUMBER NUMBER MONTH DAY YEAR 03 11 1999 1999 002 - 00, 04 07 1999 FACILITYNAME OOCKE'r NUMBER OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQ UIREMENTS OF 10 CFR %t (Check one or more) (11)
MDDE (9) 20.2201(b) 20.2203(a)(2l(v) X 50.73(a)(2)(i) 50.73(s)(2)(vin)
POWER 20.2203 (sl(1) 20.2203(a) (3) (i) 50.73(a)(2)(u) 50.73(a) (2) (x)
LEVEL (10) 100 73.71 20.2203(a)(2)(i) 20.2203(a)(3)(u) 50.73(a)(2)(iii) 20.2203(a)(2)(ii) 20.2203(a)(4) 50.73(BH2)(iv) OTHER 20.2203 (sl(2) (iii) 50.36(c)(1) 50.73(a)(2)(v) Specify in Abstract below or 20.2203(a)(2)(iv) 50.36(c) (2) 50.73(a)(2)(vii) In NAC Form 366A LICENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER SneIIere Arse Cedet George R. Madden (561} 467 - 7155 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13)
REPORTABLE REPORTABLE CAUSE SYSTEM COMPONENT MANVFACTVAEA CAUSE SYSTEM COMPONENT MANUFACTURER TO EPIX TO EPIX ev Inta SUPPLEMENTAL REPORT EXPECTED (14I MONTH DAY EXPECTED YES SUBMISSION (I( Yes, complete EXPECTED SUBMISSION DATE). X No DATE (15)
ABSTRACT /limit to 1400 spaces, /.e., approximately 1 5 single.spaced typewritten lines/ (16)
During the St. Lucie Unit 2 refueling outage 11 (SL2-11} steam generator inspection in November 1998, the tube at Row 49 Line 85 in steam generator (SG} 2B was plugged due to a wear-induced indication that penetrated 47% through wall, exceeding the plugging limit of Technical Specification 4.4.5.4.a.6. Upon review of historical data, it was determined that this indication was present, but not identified during the SL2-9 and SL2-10 examinations, and that the depth of the i.ndication was essentially unchanged during this period of operation. Therefore, this tube exceeded the plugging limit, but remained in service during operating cycles 9 and 10. Detection and subsequent plugging of this tube indication resulted from improvements in the data analysis and controls implemented for the SL2-11 inspection. Lead analysts did not inform FPL that this indication was not identified during the prior examinations. The missed detection was identified during the post outage review acti.vities.
Corrective actions include: changing data analysis guidelines for lead analysts to report conditions to FPL that may indicate a repairable degradation was not reported in a prior examination; modifying data analysis guidelines for wear-induced degradation to include instructions to screen the 100 kHz differential and 100 kHz absolute channels in addition to the 400/100 kHz differenti.al mix channel, and report flaw-like indications; and including the wear indications that were identified during the SL2-11 inspections, but not reported in SL2-10 inspections, in the training and testing of data analysis personnel.
NAC FORM 366 I6.1996)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (8-1998)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME I1) DOCKET NUMBER I2) LER NUMBER I6) PAGE I3)
SEQUENTIAL REVISION NUMBER NUMBER St. Lucie Unit 2 ~ 05000389 Page 2 of 6 1999 - 002 - 00 TEXT (If more speceis required, use additionel copies of NRC Farm 366A) I17)
Event Description On March 11, 1999, a post outage review of the steam generator (SG) [EIIS:AB:SG) tube degradation trends was being prepared for the fall 1998 refueling outage (SL2-11) steam generator examination report. It was noted that a wear-induced indication in the tube at Row 49 Line 85 of SG 2B was reported as 47% through wall and did not show any evidence of growth based on comparison to the SL2-10 examination data. This tube was plugged during the SL2-ll outage. This review confirmed that this indication was present in the SL2-10 examination data, and measured approximately the same depth, but was not reported. Although the lead review team (LRT) analysts (contractors) had made this same determination during the SL2-11 examination, attention of the FPL representative. A more extensive review on March 12, 1999 it was not brought to the determined that the indication was also present in the SL2-7, SL2-8 and SL2-9 examination data and was not reported by either the primary or secondary analysts (contractor). This review showed that the indication did not exceed the limit (40%. through wall) of plant Technical Specifications until the SL2-9plugging and later examinations. In the SL2-11 examination, the indication was not reported by the primary analyst (contractor), but was identified by the secondary analyst (contractor) through the use of a computer data screening system (CDS). The CDS system uses pre-established screening parameters that are qualified to detect degradation that is known or postulated to exist in the SGs. During the SL2-11 examination, the CDS system parameters were enhanced"to screen for potential free-span cracking, which has been reported during previous 'examinations in the St. Lucie Unit 1 (original SGs), SONGS, and Calvert Cliffs SGs. The enhanced screening parameters used for free-span cracking overlapped the same region of the tube bundle in which the diagonal support wear-induced indications occur, and resulted in detection of the wear-induced indication that previously was not reported.
Cause of the Event A barrier analysis was completed to determine the causes that contributed to this event. The causes for not reporting the indication in the SL2-10 examination were determined to be; 1) deficiencies in data analysis guideline instructions, and 2) inadequate data analyst training. In addition, the data analysis guideline did not instruct lead analysts (contractor) to report conditions to FPL that may indicate that a repairable degradation was not reported in prior examinations. This would provide earlier identification of potential problems.
A review of industry qualified examination techniques provided through EPRI shows that, for wear-induced indications, screening of the 400/100Khz differential mix channel is one of several acceptable techniques. Latitude is given for the user to specify additional channels to be screened for confirmation and to provide additional instructions. This information has been shared with EPRI for their review.
With the exception of the added instructions to screen the 100Khz differential channel for free-span cracking in SL2-11, the data analysis guideline in the SL2-10 and SL2-ll examinations were identical with respect to the screening and reporting of wear-induced indications. The guideline requires that the indication appear flaw-like on the 400/100 kHz differential mix channel, or on the 100 kHz absolute channel.
A review of SL2-11 data shows this indication maintains flaw-like characteristics considered typical of wear-induced degradation on the 100Khz differential and 100Khz absolute channels, but does not maintain them in the 400/100Khz differential mix NRC FORM 388A I8.1998)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (6-I 998)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITYNAME I1) OOCKET NUMBER I2) LER NUMBER (6) PAGE I3)
SEQUENTIAL REVISION NUM8ER NUMBER St. Lucie Upit 2 05000389 Page 3 of 6 1999 - 002 - 00 TEXT fifmore spaceis required, use edditionel copies of NRC Form 366A) I17) channel. The apparent lack of flaw-like characteristics in the 400/100Khz differential mix channel may be attributable to a longer and more gradual taper associated with some diagonal support wear-induced indications. This would explain the lack of flaw-like characteristics in the 400/100Khz differential mix channel, and provide an explanation why the indication was not reported during previous examinations. The guideline does provide latitude to report indications not specifically addressed or described within the guideline (Section 15.8), yet the indication remained unreported. Xn retrospect, the guideline should require data analysis personnel to report suspected wear-induced indications channels appear flaw-like. This logic should be applied to both primary and if any of the above secondary analysis reviews.
The individual analysts (contractor) that reviewed the data for this indication had previous St. Lucie Unit 2 experience as well as similar plant experience, and are from reputable organizations. Furthermore, their performance demonstration test results do not indicate a problem with detection or reporting of wear-induced indications. Also, data analysts (contractor) are typically limited to 8-10 hour shifts to reduce fatigue. No specific examination date, vendor organization, or work shift can be identified as a significant contributor to this event. This supports the conclusion that potential inadequacies exist in the instructions provided in the data analysis guideline, and the site specific training and testing of data analysis personnel for reporting of wear-induced indications, rather than in personnel or equipment related issues.
The current guideline does not specifically prompt the lead review analysts to report conditions to FPL that may indicate that a repairable degradation was not previously reported in a prior examination. Although this would not have eliminated the fact that the indication was not reported, it did delay the evaluation of potential problems. This again appears to be an oversight in the data analysis guideline instructions.
Analysis of SG examination data is performed in accordance with written instructions and protocol that are provided in FPL data analysis guidelines. Prior to each examination, data analysis personnel (contractor) are indoctrinated, trained, and tested to demonstrate proficiency in application of guideline instructions. Data analysis personnel are also required to pass an HPRI standardized training and testing program for Qualified Data Analyst. The data analysis process at FPL incorporates independent primary and secondary analyses for all data acquired.
Secondary analysis .utilizes computer data screening (CDS) methods to provide added assurance that all indications are reported. A team of resolution analysts (contractor) dispositions differences between primary and secondary analyses. Lead review teams (LRT) (contractor) review the resolution team output for consistency in application of guideline instructions, select indications for diagnostic examinations, select in-situ testing candidates and provide final input to the tube plugging list.
In addition to routine analysis as discussed above, reviews are completed to evaluate growth trends, assess detection performance, provide data analyst feedback, and ensure that all indications reported in a prior examination are addressed in the current examination. The lead review analysts (contractor) are instructed to use historical data to evaluate current outage results. This is typically accomplished using the data segment recall (DSR) function provided in the analysis software, or by use of raw data available on optical disks or hard drives. DSR is the first course of NRC FORM 3BBA IB.1998)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (8 1998)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE I3)
NUMBER I2)
SEQUENTIAL REVISION NUMBER NUMBER St. Lucie Unit 2 05000389 Page 4 of 6 1999 002 00 TEXT (Ifmore speceis required, use edditional copies of NRC Form 366AJ (17) action since all indications reported in the prior examination should be available in this format. The alternative is the raw data on disk. The absence of a flaw history on DSR for an indication could be used to initiate further evaluations to determine if the indication was present, but not reported in the previous examination, and if it appeared to exceed the tube-plugging limit. This in turn should alert lead personnel (contractor) to inform the FPL representative.
Current screening instructions in the data analysis guideline have identified more than 500 tubes that are affected by wear-induced degradation, which is typical for the steam generator design installed at St. Lucie Unit 2. Current instructions, however, do not account for indications that lack flaw-like characteristics in the 400/100 kHz differential mix channel, but maintain flaw-like characteristics in the 100 kHz differential or 100 kHz absolute channels. A review of indications that have remained unreported in prior examinations shows that only one indication (Row 49 Line 85 in SG 2B) has exceeded the tube-plugging limit of Plant Technical Specifications during previous operation. The additional screening requirements implemented for free-span cracking appear to be effective in reporting this form of wear-induced degradation, and should be required in the analysis instructions. Zn addition, data analysis guidelines should be modified to instruct lead analyst personnel to report conditions to FPL that may indicate that repairable degradation is not being reported in prior examinations. Data analyst training and testing should also be revised to include wear-induced indications that have not been reported in prior examinations.
Analysis of the Event This event is reportable under 10 CFR 50.73(a) (2) (i) (B) as any operation or condition prohibited by the Technical Specifications (TS) . TS 3 .4 .5 states that each steam generator shall be operable. The applicable ACTION statement states that with one or more steam generators inoperable restore the inoperable steam generator to operable status prior to increasing T, above 200'F. TS Surveillance 4.4.5.0 states that each steam generator shall be demonstrated operable by performance of the inservice inspection program. TS 4.4 .5.4.a.6 Plugging Limit means the required'ugmented imperfection depth at or beyond which the tube shall be removed from service and is equal to 40% of the nominal tube wall thickness. TS 4.4.5.4.a.7 states that a tube is unserviceable if it leaks or contains a defect large enough to affect its structural integrity in the event of an operating-basis-earthquake (OBE), a loss-of-coolant-accident (LOCA), or a steam li.ne or feedwater line break.
Contrary to the above, on March 12, 1999, FPL identified that SG 2B operated throughout operating cycle 9 and 10 with the tube at Row 45 Line 85 having a 47%
through wall wear indication.
Safety Significance The steam generator tubes are described in UFSAR section 5.4.2.1.3. The tubes are designed to allow for wall thinning and the generators are designed to minimize the potential for denting. The UFSAR discusses considerations for localized corrosion leading to tube degradation, which is the predominant degradation mechanism seen in the industry.
St. Lucie Unit 2 Design Basis Document, Volume 9, discusses reactor coolant system integrity. Et also discusses the structural integrity requirements for steam generator tubes, and provides an assessment of maximum allowable tube wall NAG FOAM 366A 18 1998)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (8.1998)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (31 NUMBER (2)
SEQUENTIAL REVISION NUMBER NUMBER St. Lucie Unit 2 05000389 Page 5 of 6 1999 002 00 TEXT fifmoro space is required, uso additional copies of NRC Form 368A) (171 degradation that can sustain the loading imposed by normal operation and postulated accident conditions. This shows that a maximum allowable tube wall degradation of 63% is within the design basis for the steam generator tubing.
Mechanical wear in the Unit 2 steam generators is a result of a design flaw in the fabrication of the units. The design flaw was discovered following a primary to secondary leak at another plant and at St. Lucie Unit 2 during Cycle 2 shortly thereafter. In the tube leak event at St. Lucie 2, the leakage was limited to approximately 20 gallons per day (gpd) . Air ejector monitors readily detected it, and the unit was shutdown within a few days. The historical tube leaks at SONGS Unit 2 and St. Lucie Unit 2 occurred in a region of the tube bundle that was analyzed to be susceptible to rapid growth rates. Preventative tube plugging was completed at St. Lucie Unit 2 to remove the susceptible tubes from service ~ Therefore, it is currently unlikely that wear degradation would result in through wall penetration and primary to secondary leakage in one or two cycles of operation. Extensive inspections have been completed at each refueling outage since that time, and the rate of wear has been low.
After implementation of preventive plugging measures, it was not expected that the rate of wear-induced damage would result in a through wall penetration after one or two cycles of operation. Furthermore, the potential effects associated with a through wall penetration scenario have been shown to have no effect on safety. A design basis steam generator tube rupture (SGTR) accident, as described in Chapter 15 of the St. Lucie UFSAR, is defined as a double-ended guillotine break of a tube that results in initial primary to secondary leak rates in excess of 300 GPM. ABB/CE has performed prototypical laboratory testing to empirically determine the leak rate from tube defects that were intended to simulate wear defects, produce by tube supports.
These tests showed" that in all cases, when wear-initiated degradation is lesq than the structural limit of the tubing, primary to secondary leakage would not be expected to occur under normal operation or postulated accident conditions. Even in the majority of cases when such degradation exceeds the structural limit, a through wall penetration of this type will result in a leak rate less than one GPM, and would not suddenly leak in an uncontrolled manner. These test results have been further substantiated by the slow steady leak rates that occurred during early operation from through wall penetrations in the SONGS Unit 2 and St. Lucie Unit 2 steam generators.
Therefore,'he leak rates that could result from wear defects would be within the current Technical Specification limits of the unit and would, therefore, represent an operational concern but not a safety concern.
As a result, potential tube defects from mechanical wear are not considered as a possible initiating event of a SGTR accident but, rather, as a potential increase in the normal secondary system radionuclide inventory that is used as an initial condition for other Chapter 15 accident analyses'econdary system radionuclide inventories assumed in the UFSAR Chapter 15 safety analysis are based on one percent failed fuel and a continuous one GPM primary to secondary leak rate. As discussed above, the most severe leak rates associated with typical through wall wear penetrations are typically much less than one GPM. In addition, operation with one percent failed fuel is considered highly unlikely. Hence, actual secondary system radionuclide inventories are expected to be much less than those assumed in the accident analysis. As a result, the radiological consequences associated with postulated wear-induced tube leakage will be bounded by those accidents currently described in Chapter 15 of the UFSAR.
NRC FORM 309A (9.1998)
0 NRC FORM 3BBA U.S. NUCLEAR REGULATORY COMMISSION IB.I 990)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITYNAME (1) DOCKET NUMBER (2I LER NUMBER (6) PAGE (3)
SEQUENTIAL REVISION NUMBER NUMBER St. Lucie Unit 2 05000389 Page 6 of 6 1999 - 002 - 00 TEXT ilfmoro spece rs required, use edditionel copies of lVRC Form 3S6A) (17)
It should also be noted that operation with a continuous one GPM primary to secondary leak rate is an unrealistic assumption. The St. Lucie 2 Technical Specifications do not permit operation'f total primary to secondary leakage exceeds one GPM through if all steam generators, or leakage from any one steam generator exceeds 720 gallons per day (0.5 GPM). St Lucie performs primary system water inventory balances at least every 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, which are capable of detecting leak rates of this magnitude.
In addition, secondary system radiation monitors are capable of detecting increases in secondary system radiation that would result. from primary to secondary leaks. In either case, an orderly reactor shutdown would likely be performed before secondary system radionuclide inventories reached the levels assumed in the accident analysis.
Based on the above discussion, wear-induced degradation in the steam generators is not a safety concern.
In addition, as discussed above, maximum allowable degradation that will sustain the loading imposed by normal operation and postulated accident conditions is 63% through wall penetration. Since the degradation in Row 49 Line 85 in SG 2B was 47% through wall, it did not exceed the design basis, and structural integrity was not compromised. Therefore, the tube was not considered unserviceable as described in Plant Technical Specification Section 4.4.5.4.a.7. Based on the above discussion, the operation during cycles 9 and 10 with the degradation in the tube at Row 49 Line 85 at 47% through wall did not adversely affect the health and safety of the public.
Corrective Actions
- 1. Include instructions in data analysis guidelines for lead analyst personnel to report conditions to FPL that may indicate that repairable degradation has not been reported in prior examinations.
- 2. Modify data analysis guidelines for wear-induced degradation to include instructions to screen the 100 kHz differential and 100 kHz absolute channels in addition to the 400/100 kHz differential mix channel, and report flaw-like indications.
- 3. Include wear indications that were reported in SL2-11 inspections, but not reported in SL2-10 inspections, in the training and testing of data analysis personnel for future outages.
Failed Components Identified None Similar Events LER 389-1998-008 NRC FORM 300A (0.1990)