|
---|
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
[Table view] |
Text
ACCELERATED DISTRIBUTION DEMONSTPA.TION SYSTEM r REGULATORY INFORMATION DISTRIBUTXON SYSTEM (RXDS)
ACCESSXON NBR:9106110130 DOC.DATE: 91/06/04 NOTARXZED: NO DOCKET FACIL:50-335 St. Lucie Plant, Unit 1, Florida Power & Light Co. . 05000335 AUTH. NAME AUTHOR AFFILIATION WACHTEL,P.K. Florida Power & Light Co.
SAGER,D.A. "
Florida Power & Light Co.
RECIP.NAME RECIPIENT AFFILIATION
SUBJECT:
LER 91-003-00:on 910506,heater drain pump 1A tripped & 4 s later SG feedwater pump 1A tripped causing turbine runback., D Caused by possible grounding of heater hi-hi level switch.
Circuit breaker 27, replaced.W/910604 ltr.
DISTRIBUTION CODE: XE22T COPIES RECEIVED:LTR t ENCL SIZE:
TITLE: 50.73/50.9 Licensee Event Report (LER), Tncident Rpt, etc.
NOTES "
RECIPIENT COPIES RECIPIENT COPIES D ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-2 LA 1 1 PD2-2 PD 1 1 D NORRIS,J 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1
.AEOD/ROAB/DS P 2 i 2 NRR/DET/ECMB 9H 1 1 NRR/DET/EMEB 7E 1 1 NRR/DLPQ/LHFB10 1 1 NRR/DLPQ/LPEB10 1 1 NRR/DOEA/OEAB 1 1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1 NRR/DST/SICB8H3 1 1 NRR/DSQ A~BBD1 1 1 NRR/DST/SRXB 8E 1 1 RPG -" 2 1 1 RES/DSIR/EXB 1 1 RGR I-+~0% 1 1 EXTERNAL EG&G BRYCE ~ J ~ H 3 3 L ST LOBBY WARD 1 NRC PDR 1 1 NSIC MURPHY,G.A 1 1 NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 D
D D
NOTE TO ALL "RIDS" RECIPIENTS:
S PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOiVI Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33 ~
gf
P.O. Sox 1 8, Ft. Pierce, FL 34954-0128 FPL JQN Q4 $ 91 L-91-155 10 CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:
Re: St. Lucie Unit 1 Docket No. 50-335 Reportable Event: 91-03 Date of Event: May 6, 1991 Manual Reactor Trip Following a Turbine Runback Due to E i ment Failure The attached Licensee Event Report is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.
Very truly yours, D. A. ger Vice r sident St. Lu e Plant DAS:GRM:kw Attachment cc: Stewart D. Ebneter, Regional Administrator, USNRC Region Senior Resident Inspector, USNRC, St. Lucie Plant II DAS/PSL N441 9l061$ 01-"'0 Olr.r604' rrr aDOCV. ~>SC>O03:-:-
PDf" an FPL Group company
~ .r r 4r 8 JU
U.S. NUCLEAR REGULATORY COMMISSION APNTOITDDAWN1 $ 550050l F PL Faoalrrire of CXPSNW 40005 NRC oorrrr SQf DCTAAATTDILATIINPrll INIPOAWTD CC001T IPTN TN0 INCITAAllCNCCTACOICN te-ssf LICENSEE EVENT REPORT (LER) 5015NDT: 500 5005 ICITWAITICCANCNIDINITNCTIAT IAITXNTDTAAAICTo TIN IKCCTCS No INPCPDD NIACCINNTWTANCNIP0005 Ila IADACNIINWAATCTTY NAWNIITAWADDNIION, DC 505Nl NCI ro TIN PTTNICIXTII%DUCTION INOICCT f 0IWCI04OIINNCP NACÃACNTAN)500XCT,WANNIOTCPADC505ICL FACILITYNAME (1) DOCKET NUMBER (2) PAGE 3 St. Lucie Unit 1 050003351 0 0 4 Tl LE(4) Manual Reactor Trip Following a Turbine Runback Due to Equipment Failure EVENT DATE (5) LER NUMBER (6) REPORT DATE m OTHER FACILITIES INVOLVED(8)
DAY YEAR YEAR S AL MONTH DAY YEAR FACILITYNAMES DOCKET NUMBER(S)
N/A 0 0 5 069 1 9 1 0 0 3 0 0 0 6 0 4 9 1 N/A 05000 THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR:
OPERATING Check one or more of the followin (11)
MODE (9) 20.402(b) 20.405(c) X 50.73(a)(2)(iv) 73.71(b)
POWER 20.405(a)(1 )(i) 50.36(c)(1) 50.73(a)(2)(v) 73.71(c)
LEVEL (1o) 0 9 6 20.405(a)(1)(ii) 50.36(c)(2) 50.73(a)(2)(vii) 0 IHER (Specify in Abstract 20.405(a)(1 )(iii) 50.73(a)(2)(i) 50.73(a)(2)(viii)(A) below and in Text 20.405(a)(1)(iv) 50.73(a) (2) (ii) 50.73(a)(2)(viii)(B) NRC Form 366A) 20.405(a)(1)(v) 50.73(a) (2)(iii) 50.73(a)(2)(x)
LICENSEE CONTACT FOR THIS LER 12 NAME TELEP ONE NUMBER AREA CODE Patricia K. Wachtel, Shift Technical Advisor 4 0 7 465 -3550 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13 MANUFAC- REPORTABLE MANUFAC- REPORTABLE CAUSE SYSTEM COMPONENT TO NPRDS CAUSE SYSTEM COMPONENT TURER TO NPRDS S J L I S 0 4 0 S J P S U069 I I I SUPPLEMENTAL REPORT EXPECTED 14 EXPECTED MONTH DAY YEAR SUBMISSION YES (lfyes, complete EXPECTED SUBMISSlOfrf DATE) X NO DATE (15)
ABSTRACT (Limit to 1400 spaces.i.e. approximately fifteen single-space typewritten lines) (16)
On May 6, 1991, St. Lucie Unit 1 was in Mode 1 and holding power at 96% to complete a Nuclear Delta-T Power Calibration before resuming full power operation following a scheduled shutdown. The 1A Heater Drain Pump tripped at 0508 and, four seconds later, the 1A Steam Generator Feedwater Pump tripped causing a turbine runback. The unit was manually tripped at 0509 at the direction of the Nuclear Plant Supervisor in anticipation of an automatic reactor trip and Standard Post Trip Actions were performed. The unit was then stabilized in Mode 3, Hot Standby.
The manual reactor trip was the result of a turbine runback initiated when both the 1A Heater Drain Pump and the 1A Steam Generator Feedwater Pump tripped. An investigation revealed a possible grounding of the 5A Feedwater Heater Hi-Hi level switch which, in turn, opened Circuit Breaker 27 on the 120 VAC Vital Static Uninterruptible Power Supply. This would have caused the normal drain valves to close on several secondary Feedwater Heaters and the alternate drain valves to open. It was also found that the pressure sensing element setpoint for the 1A SGFP had drifted high from the normal value of 275 psig to 291 psig. The end result was a low suction pressure condition on the Feedwater Pump suction line and the trip of the 1A Steam Generator Feedwater Pump on low suction pressure.
The immediate Corrective Actions implemented as a result of this event include: testing and replacing Circuit Breaker 27 as a precautionary measure, cleaning and testing the 5A Feedwater Heater Hi-Hi level switch, and lowering the setpoint of the 1A Steam Generator Feedwater Pump to its normal value of 275 psig.
FPL Facsimile of NRC Form 366 (6-89)
FPL Facslmto ot NR~ earn 366
(~d, U.S. NUCLEAR REGULATORY COMMLSSION ~ cao$ Nck $ <ooaoo
$ $ eoea otaolo LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION $e oeiea
~aoouo~
EN$ $ATEO BAXNoQI IKIPQNR loOQPLYoolll1Ho ooOfNATCN CCuf CICN auasr: a$ $ aoo~ ooooeona mwcwa aooxs asrou$ $ oo ue euocu pa$ $ ua $ ooaooaooajuuan coaoaooa ooeeeeoe . Oc $ $ Ma N$ $ o ae oJpoNKÃ% fcDUclKNRoxco (
$ ~$ oouaao$ $ $ a awwnenwo aoae;vooeoemoo oo $ $ 5$ $
FACILITYNAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)
't.
YEAR EQUEN TIAL REVISIO Lucie Unit 1 NUMBER NUMBER 0500033591 0 0 3 0 0 0 2 0 4 TEXT (Ifmore spaceis required, use additional NRC Form 366A's) (17)
On May 6, 1991, St. Lucie Unit 1 was in Mode 1 and holding at 96% power to perform a Nuclear Delta-T Power Calibration prior to resuming full power operation. A unit shutdown had been performed to facilitate Control Element Assembly (CEA) (EIIS:AA) testing required every ninety days.
I While the unit was stabilized at 96% power, the board Reactor Control Operator (RCO) noted that there were amperage swings on the 1A Heater Drain Pump (HDP) (EIIS:SN) meter. At approximately 0508, the 1A Heater Drain Pump tripped and, within four seconds, the 1A Steam Generator Feedwater Pump (SGFP) (EIIS:SJ) tripped on low suction pressure which caused a turbine runback.
The board RCO immediately set up the turbine for a 10 MW/min downpower while the desk RCO and extra RCO initiated emergency boration and took manual control of the Control Element Drive Mechanism Control System (CEDMCS) ( EIIS:AA) to insert the control rods. Both Steam Generator (SG) (EIIS:AB) levels were decreasing and Pressurizer (EIIS:AB) pressure was increasing . When the Reactor Coolant System (RCS) (EIIS:AB) pressure reached 2340 psia, the Nuclear Plant Supervisor instructed the board RCO to manually trip the reactor and turbine to avoid an automatic reactor trip on High Pressurizer Pressure (setpoint, 2400 psia). Standard Post Trip Actions were performed and all safety functions were met.
During the post trip recovery, level in the 1B SG rapidly increased and a control room operator noted that the 'B'ain Feedwater Regulating Valve (MFRV) (EIIS:SJ) was approximately 70% open, whereas it should have fully shut upon the turbine trip. At 88% level in the 1B SG, the RCO closed the valve to restore SG water level to 65%. Auxiliary Feedwater Actuation Signal-1(AFAS) (EIIS:BA) occurred normally on. the 1A SG after level decreased to the AFAS setpoint of 19% while the 1B SG never reached its AFAS setpoint due to the MFRV failure. The 1A and 1C Auxiliary Feedwater Pumps (AFW) (EIIS:BA) started and supplied water to the 1A SG and the RCO placed the 15%
Feedwater Bypass Valves (EIIS:S J) in automatic. With SG level controllers in automatic and the 1B SGFP available, both SG levels then returned to 65% narrow range level.
Reactor Trip Recovery, Emergency Operating Procedure-2, was completed with two sets of satisfactory Safety Function Status Checks. Emergency boration was halted, AFAS was reset, and the unit was stabilized in Mode 3, Hot Standby.
The cause of the 1A Heater Drain Pump and the 1A Steam Generator Feedwater Pump trips can be attributed to corrosion and a possible grounding of the 5A Feedwater Heater Hi-Hi level switch (EIIS:
JB), LS-11-28A, which is powered from Circuit Breaker 27 in the 120 VAC Vital Static Uninterrup-tible Power Supply (SUPS) (EIIS: EE). Circuit Breaker 27, which supplies power to both the A & B trains of the 3, 4, and 5 Feedwater Heater Controls and the A, B, C, and D Moisture Separator Reheater Drain Collector (EIIS:SN) normal drains, was found in the tripped condition atter the plant trip. The failure of this circuit resulted in the normal drains of the 3 and 5 Feedwater Heaters to fail closed and the alternate drains of all Feedwater Heaters to fail open. The decreasing level in the shell side of the A & B Feedwater Heaters caused the HDP discharge valves to close and the FPL Facsimile of NRC Form 366 (6-89)
FPL FCCCIRT'Io of U.S. NUClEAR REGULATORY COMMISSCN APPRORO DAO NIL01000100
~
NRC Drm368 (649I fXPTRO: AOCRT LICENSEE EVENT REPORT (LER) 000aAATTO TLATXNPTR IRTPTPRC TOCTAAPLTTRTN TNC CTTAATORDCLLTCROI TRTXXCI: RLT TRT, PCRRNTT TOLARNTRIROARNTC TAATXNORTAATT TO TlC TEXT CONTINUATION TROOTXI APO ICPCRT0 ANACXLRNTOIARCR P'4000 UR NXAEARRTOAATCRP ATPRROCR. DC STOL R00 TO OR P JPTRWON TROVCOCR PIOLXCT I 01 0001 OALOTPCC OP WNAOTLRNT0000 OXXXT,TIANTNCTTPLDC TCTCL FACILITYNAME (1 ) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)
YEAR EQUENTIAL 'EVISIO St. LUCie Unit 1 NUMBER .. NUMBER 0 500 0335 9 1 0 0 3 0 0 0 3 0 4 TEXT (fimore spaceis reguf'red, use additional NRC Form 366A's) (17) suction pressure for the SGFP to decrease. The HDP tripped on either low flow or at the low level setpoint in the 4A Feedwater Heater. The resulting low suction pressure condition in the SGFP suction line caused the 1A SGFP to trip at 291 psig. Normal setpoint for the feedwater pump trip is 275 psig; a subsequent Instrumentation and Control test of the pressure sensing element indicated that its setpoint had drifted high from the normal value of 275 psig to 291 psig.
The manual reactor trip by the utility operators was in anticipation of an automatic reactor trip on High Pressurizer Pressure after the turbine runback caused by the 1A SGFP trip.
This event is reportable to the NRC under 10CFR50.73(a)(2)(iv) as any event or condition that results in a manual or automatic actuation of any Engineered Safety Feature, including the Reactor Protection System .
The plant response during this event was bounded by Section 15.2.8 of the St. Lucie Unit 1 FUSAR, "Loss of Normal Feedwater Flow." The plant response was much more conservative than that described in the FUSAR analysis for several reasons: 1) Only one Steam Generator Feedwater Pump stopped whereas the FUSAR assumes a total loss of feedwater. 2) The reactor trip was manually initiated prior to exceeding any protective setpoints. 3) RCS pressure remained below the setpoint of the Power Operated Relief Valves and the Pressurizer Code Safety Valves.
The loss of the 1A HDP and the 1A SGFP resulted in a main turbine runback and a reduction in normal feedwater flow. The turbine runback is initiated when one of the two running SGFPs trip and turbine load, as measured by the main turbine's first stage pressure, is greater than 60% or both HDPs trip and turbine load is greater than 92%. The turbine runback is not required for reactor safety; it is intended to reduce the turbine steam demand in response to the reduced feed flow and subsequent decrease in SG feedwater inventories. Had the turbine runback failed to activate following the 1A SGFP trip, the Reactor Protective System (RPS) (EIIS:JC) would have automatically tripped the reactor on Low SG level and then tripped the turbine. This would have assured sufficient SG feedwater inventories to provide an adequate heat sink for the primary system.
The Auxiliary Feedwater Actuation System functioned as required when the 1A SG level reached the AFAS setpoint of 19% and the 1A and 1C AFW pumps automatically started, initiating auxiliary feedwaterflowtothe1A SG. Operatormitigationofthe18 Main Feedwater Regulating Valve failure precluded SG level from reaching the 90% level setpoint for tripping off the remaining SGFP.
Therefore, with the SG level controllers in automatic and the 18 SGFP available, level was restored to the 65% narrow range level and the unit was stabilized in Mode 3.
The St. Lucie Training Department prepared a simulator scenario which was similar to this event. The results from that simulation were compared with the actual plant response to this event and was a validation of the root cause of this reactor trip.
FPL Facsimile of NRC Form 366 (6-89)
PPL PocoIITIle oI U.S. NUCLEAR REGULATORY COMMISSION Iff>>OTTOCa>> HOOT TOO IOI NR( carTT 666 Cfff>>W OOOOT
<6.66t LICENSEE EVENT REPORT (LER) ccoAATTO TLf>>CHfOI Icffaf>> TO ~Y WITHTIfooaofJATCH OCALCCOCH IOTACOT.'SLO IoTO fOHWII>>OOWHTITOfcfff>>O>>foffHTICSTOAATC TO TIO TEXT CONTINUATION IKCCMI If>>Icfalfo If MHAaol>>ITTHAHCH ooTL UO>>>>LCAHIH>>AAIOHT cao>>oooHwwooeTTCWI.oc IONA Ho Too>> foffoocfw onLCTcw ffcACCTI OI >>O IOIL Cf>>CC Cf IAHKKMHTAICITL>>CCT WWOOHOTTfc OC TTOOO FACILITYNAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)
YEAR EQUENTIAL REVISIO St. Lucie Unit 1
'UMBER NUMBER 0 5 0 0 0335 9 0 0 3 0 0 0 40 0 4 TEXT (Ifmore spaceis required, use additional hlRC Form 366A's) (17)
The plant response during this reactor trip was observed to be normal for the given conditions. All safety related systems functioned as designed and all safety functions were met. At no time during this event was the health and safety of the public endangered.
I T C'.
Circuit Breaker 27inthe120VAC Vital SUPSwas multi-amptestedbythe ElectricalMaintenance Department and found to be satisfactory, as was its associated fuse. As a precautionary measure, Circuit Breaker 27 was replaced, then tested for grounds, and instrumented for amperage.
- 2. The instrumentation and Controls (l8C) Department inspected all solenoids and level switches associated with Circuit Breaker 27.
- 3. The 5A Feedwater Heater Hi-Hi level switch, LS-11-28A, was cleaned and tested to be satisfactory by the I&C Department.
- 4. I8C lowered the low pressure trip setpoint for the 1A SGFP to its normal value of 275 psig.
- 5. System Engineering and Operations tested the 1B MFRV before power ascension. The cause of the valve's misoperation was due to a grounding relay, K2, failing to properly ground out the level control signal after a turbine trip. The K2 relay had dirty contacts and was replaced.
- 6. A design change is under evaluation to split the Unit 1 A and B Feedwater Heater level control circuits so they are powered by separate breakers, which is similar to the Unit 2 design.
n LIII Magnetrol Liquid Level Switch Model Number 601 MPX United Electronics Controls Pressure Switch Type J120 Model Number 9852 376 I I I The last previous manual reactor trip is described in LER¹335-90-07, "Manual Reactor Trip following leakage of DEH control fluid due to the installation of improperly sized O-Rings.H FPL Facsimile of NRC Form 366 (6-89)