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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17292B7421999-07-20020 July 1999 LER 99-001-00:on 990628,ESF Signal Closed All Eight MSIVs While Plant Was Shutdown.Caused by Failure of Relay RPS-RLY-K10D.Subject Relay Was Replaced & Tested on 990630. with 990720 Ltr ML17292B4451998-10-27027 October 1998 LER 98-012-01:on 980715,failure to Comply with Requirements of TS SR 3.8.4.7 Was Noted.Caused by Inadequate Work Practices.Training Session Was Held with Personnel.With 981027 Ltr ML17284A7561998-09-0303 September 1998 LER 98-013-00:on 980805,ESF Actuations Were Noted Due to Deenergization of Vital Electrical Bus SM-8.Caused by Inadequate Direction in Troubleshooting Plan.Will Conduct Training for Engineering Personnel.With 980903 Ltr ML17284A7571998-09-0202 September 1998 LER 98-014-00:on 980807,completion of TS 3.8.1.F Required Shutdown Due to Inoperability of EDG-2 Was Noted.Caused by Degraded Voltage Regulator for DG-2.Replaced Voltage Regulator & Associated Scrs.With 980902 Ltr ML17284A7551998-09-0202 September 1998 LER 98-015-00:on 980808,discovered Reactor Coolant Pressure Boundary Leak During Shutdown Conditions.Caused by Leakage from Socket Weld (Fwb 63) on Elbow Connection.Failed Piping Connection Was Replaced.With 980902 Ltr ML17284A7311998-08-17017 August 1998 LER 98-012-00:on 980716,determined That 24-month SR 3.8.4.7 Had Not Been Fulfilled within Specified Frequency.Caused by Inadequate Work Practices.License Requested & Received Enforcement Discretion Re Battery Svc test.W/980817 Ltr ML17284A7121998-07-23023 July 1998 LER 98-006-01:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of 10CFR50,App R Calculations for High Impedance Faults.Caused by Inadequate Work Practices.Implemented Procedural Changes ML17284A6951998-07-17017 July 1998 LER 98-011-00:on 980617,ECCS Pump Room Flooding Was Noted Due to FP Sys Pipe Break.Caused by Inadequate Design of FP Sys.Detailed Review of FP Sys Design Was Conducted. W/980717 Ltr ML17284A6961998-07-15015 July 1998 LER 98-010-00:on 980615,TS Required Shutdown Due to Inoperability of TIP Sys Isolation Valve Was Noted.Caused by Improper Installation of TIP Tubing.Reattached Affected Tubing & Inspected Other TIP tubing.W/980715 Ltr ML17284A6731998-07-0101 July 1998 LER 98-009-00:on 980606,nuclear Steam Supply Shutoff Sys Group 3 & 4 Isolations During Testing Was Noted.Caused by Procedural Deficiency.Counseled Individuals Involved in preparation.W/980701 Ltr ML17284A6651998-06-24024 June 1998 LER 98-007-00:on 980530,inadvertent Full Scram & Division 1 ECCS Injection Was Noted.Caused by Failure to Meet Mgt Work Practice Expectation When Encountering Deficient Procedure. Incident Review Board Convened to Review event.W/980624 Ltr ML17284A6641998-06-24024 June 1998 LER 98-008-00:on 980531,inadvertent Full Scram During RPV Leak Testing in Mode 4 Was Noted.Caused by Change in Mgt Techniques.Revised Procedures to Take Into Account Addl Water Head in Pressure Sensing lines.W/980624 Ltr ML17284A6631998-06-19019 June 1998 LER 98-006-00:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of App R Calculations for High Impedance Fault Analysis.Caused Indeterminate. Implemented Procedural Changes Involving Operator Action ML17284A6551998-06-0404 June 1998 LER 98-005-00:on 980506,potential for Failure of RHR Sys Valve to Close on Isolation Signal Was Noted.Caused by Design Deficiency.Caution Tag Was Placed on RHR-V-40 Control Switch to Inform Plant Operators of limitation.W/980604 Ltr ML17284A6421998-06-0101 June 1998 LER 98-004-00:on 980502,determined That Primary Containment Penetration Overcurrent Protection Does Not Meet Reg Guide 1.63 Requirements.Caused by Inadequate Design Changes. Installed Addl Fuse in RHR-MO-9 circuit.W/980601 Ltr ML17292B3281998-04-0909 April 1998 LER 98-002-00:on 980311,reactor Scram & Plant Transient Occurred,Due to Failed Closed Main Steam Isolation Valve. Caused by Loss of Pneumatic Actuating Supply Pressure. Problem Evaluation Request Written for Failure of MS-V-22D ML17292B3291998-04-0909 April 1998 LER 98-003-00:on 980311,WNP-2 Experienced SCRAM Signal as Result of Low Rpv.Caused by Less than post-SCRAM Operational Strategy for Resetting SCRAM Signal in Conditions.Changes in post-SCRAM Operational Strategy implemented.W/980409 Ltr ML17292B2661998-03-0404 March 1998 LER 98-001-00:on 980203,automatic Start of HPCS EDG Was Noted.Caused by Operator Error.Operations Crew Stabilized Plant at Approximately 75% Reactor Power & Investigation of Event Was initiated.W/980304 Ltr ML17292B1111997-11-10010 November 1997 LER 97-011-00:on 971010,HPCS Battery Charger Failed.Caused by Failure of a Phase Firing Control Circuit Board Due to Aging During 7 Yrs of Use.Hpcs Sys Was Immediately Declared inoperable.W/971110 Ltr ML17292B1151997-11-0707 November 1997 LER 97-010-00:on 970906,discovered That TS SR 3.4.5.1 for Identified Portion of RCS Total Leakage Would Not Be Able to Perform within Time Limits of SR 3.0.2.Caused by Inadequate Methods.Method of Meeting SR 3.4.5.1 Established ML17292B0641997-09-24024 September 1997 LER 97-004-01:on 970327,plant Operators Manually Scrammed Reactor as Required by TS Due to Indication of Entry Into Region a of power-to-flow Map.Caused by Inadequate Attention to Detail.Established Event Evaluation teams.W/970924 Ltr ML17292B0241997-08-18018 August 1997 LER 97-009-00:on 970717,discovered Error in Recently Performed Inservice Testing procedure,OSP-TIP/IST-R701. Caused by Procedure Inadequacy.Plant Procedure OSP/TIP/IST-R701 Will Be changed.W/970818 Ltr ML17292B0291997-08-15015 August 1997 LER 97-008-00:on 970716,wire Seal Used to Lock Containment Instrument Air Pressure Control valve,CIA-PCV-2B,found Not Intact.Cause of Misadjustment of CIA-PCV-2B Unknown.Event Will Be Communicated to Plant employees.W/970815 Ltr ML17292B0201997-08-15015 August 1997 LER 97-S01-00:on 970718,failure to Take Compensatory Measure for Inoperative Microwave Security Zone Occurred. Caused by Personnel Error.Training Will Be Conducted W/ Appropriate Members of Security force.W/970815 Ltr ML17292A9481997-07-23023 July 1997 LER 97-007-00:on 970611,voluntary Rept of Automatic Start of DG-1 & DG-2 Was Experienced.Caused by Undervoltage Condition on Electrical Busses SM-7 & SM-8.Circulating Water Pump CW-P-1C Control Switch Placed in pull-to-lock.W/970723 Ltr ML17292A9201997-06-26026 June 1997 LER 97-006-00:on 970527,non-performance of Surveillance Requirement 3.6.1.3.2 for Blind Fanges,Was Noted.Caused Because Misunderstanding of Intent of Specs.Added Five Structural Assemblies for SP.W/970626 Ltr ML17292A8331997-04-28028 April 1997 LER 97-004-00:on 970327,plant Operators Manually Scrammed Reactor as Required by TS Due to Entry Into Region a of power-to-flow Map Following Planned Trip of Single Mfp. Event Evaluation teams,established.W/970428 Ltr ML17292A8311997-04-28028 April 1997 LER 97-005-00:on 970327,valid Reactor Scram Signal Received Due to Low Water Level Condition During Preparations for SRV Testing.Caused by Risks & Consequences of Decisions Not Completely Identified.Restored Water level.W/970428 Ltr ML17292A8251997-04-21021 April 1997 LER 97-003-00:on 970320,notification of Noncompliance W/Ts as TS SRs for Response Time Testing Were Not Being Met for Specified Instrumentation in Rps,Pcis & Eccs.Requested Enforcement Discretion for One Time exemption.W/970421 Ltr ML17292A7431997-03-20020 March 1997 LER 97-002-00:on 970218,determined That Rod Block Monitor (RBM) Calibr Values Were Not Set IAW Tech Specs.Caused by Calibr Procedures Inadequacies.Revised & re-performed RBM Channel Calibr procedures.W/970330 Ltr ML17292A7401997-03-13013 March 1997 LER 97-001-00:on 970211,reactor Water Cleanup Sys Blowdown Flow Isolation Setpoint Was Slightly Above TS Allowable Valve Occurred Due to Calculation Error.Lds Fss LD-FS-15 LD-FS-16 Were Declared inoperable.W/970313 Ltr ML17292A6641997-01-22022 January 1997 LER 96-009-00:on 961220,miscalculation of Instantaneous Overcurrent Relay Settings Resulted in Inoperability of safety-related Equipment.Caused by Utilization of Inappropriate Design.Testing Was completed.W/970122 Ltr ML17292A6461997-01-0606 January 1997 LER 96-008-00:on 961205,failure to Comply with TS Action Requirement for Emergency Core Cooling Sys Actuation Instrumentation Occurred Due to Unidentified Inoperability Condition.Pmr initiated.W/970106 Ltr ML17292A6371996-12-19019 December 1996 LER 96-007-00:on 961122,electrical Breakers Were Not Seismically Qualified in Test/Disconnect Position.Circuit Breaker Mfg Did Not Consider Raced Out Breaker Position During Testing.Relocated Circuit breakers.W/961217 Ltr ML17292A4121996-08-0808 August 1996 LER 96-006-00:on 960709,average Power Range Monitor Rod Block Downscale Surveillance Not Performed Prior to Entry Into Mode 1.Caused by long-standing Misinterpretation of Requirements of Tss.Procedures revised.W/960808 Ltr ML17292A3801996-07-24024 July 1996 LER 96-004-00:on 960624,plant Was Manually Scrammed by Control Room Personnel Due to Reactor Water Level Transient Experienced During Testing of Digital Feedwater Sys.Caused by Programming Error.Sys Was corrected.W/960724 Ltr ML17292A3771996-07-24024 July 1996 LER 96-005-00:on 960624,determined Missed Surveillance Test Re Channel Check of Average Power Range Monitor.Caused by Inadequate Procedures.Revised Surveillance Procedure Re When APRM Checks Must Be performed.W/960724 Ltr ML17292A3641996-07-12012 July 1996 LER 96-003-00:on 960615,required Surveillance Test Not Performed When Required by TS 3.4.1.3.Caused by Inadequate Procedures.Implementing Surveillance Procedure & Reactor Plant Startup Procedures revised.W/960712 Ltr ML17292A3361996-06-20020 June 1996 LER 96-002-00:on 960504,critical Bus SM-8 Lost Power When Supply Breaker 3-8 Tripped.Caused by Personnel Error. Operators Counselled & Procedures revised.W/960620 Ltr ML17292A2861996-05-24024 May 1996 LER 96-001-00:on 960425,inadvertent ESF Actuations Occurred Due to Tripping of Temporary Power Supply to IN-3.Caused by Personnel Error.Operations Restored to IN-3 Loads & Reset ESF actuations.W/960524 Ltr ML17291B0891995-10-19019 October 1995 LER 95-011-00:on 950919,failed to Comply W/Ts SR for RCIC Sys Due to Analysis Deficiency That Resulted in Inadequate Surveillance Test Procedure.Surveillance Procedure Revised to Correct deficiency.W/951019 Ltr ML17291A9021995-07-0707 July 1995 LER 95-010-00:on 950609,HPCS DG Declared Inoperable Due to Discovery That TS Test Method Incomplete.Caused by Inadequate Testing Procedure.Test Procedure for HPCS DG Reviewed & Special Test Procedures written.W/950707 Ltr ML17291A9031995-07-0707 July 1995 LER 95-009-00:on 950607,inadvertent MSIV Closure Occurred During Surveillance Test Due to Poor Communication Between Test Team.Determined That MSIV Closure Not Valid Because Closure Not Triggered by Plant conditions.W/950707 Ltr ML17291A8501995-06-0808 June 1995 LER 95-006-01:on 950405,reactor Scram Occurred During Surveillance Testing Due to Protective Sys Relay Failure. Replaced Failed Relay Before Plant Startup ML17291A8101995-05-12012 May 1995 LER 95-008-00:on 940125,TS Wording Lead to Potential TS Violation.Caused by Lack of Clarity in Ts.Submitted Improved TS for Plant to Provide Addl clarity.W/950512 Ltr ML17291A7841995-05-0505 May 1995 LER 95-007-00:on 950222,emergency Diesel Start Occurred Due to Voltage Transient on BPA Grid.Confirmation Was Received at 17:51 H That Disturbance Had Originated in BPA Grid ML17291A7801995-05-0404 May 1995 LER 95-006-00:on 950405,main Turbine Trip Occurred During Performance of Surveillance Test Due to Protective Sys Relay Failed.Replaced Failed Relay Before Plant startup.W/950504 Ltr ML17291A7851995-05-0303 May 1995 LER 95-005-00:on 950222,inoperable IRM Had Been Relied Upon to Meet TS Requirements During Reactor Startup.Caused by Lack of Neutron Source to Test Instrumentation. Sys Knowledge Gained Will Be incorporated.W/950503 Ltr ML17291A7071995-03-25025 March 1995 LER 95-004-00:on 950226,malfunction in Main Turbine DEH Control Sys Caused All Four High Pressure Turbine Governor Valves to Rapidly Close.Caused by Blown Fuse.Suspected Faulty Circuit Card replaced.W/950325 Ltr ML17291A7011995-03-20020 March 1995 LER 95-002-00:on 950218,automatic Reactor Scram Occurred. Caused by Erroneous Positioning of Control During Performance of Scheduled Periodic Functional Test.Control repositioned.W/950320 Ltr 1999-07-20
[Table view] Category:RO)
MONTHYEARML17292B7421999-07-20020 July 1999 LER 99-001-00:on 990628,ESF Signal Closed All Eight MSIVs While Plant Was Shutdown.Caused by Failure of Relay RPS-RLY-K10D.Subject Relay Was Replaced & Tested on 990630. with 990720 Ltr ML17292B4451998-10-27027 October 1998 LER 98-012-01:on 980715,failure to Comply with Requirements of TS SR 3.8.4.7 Was Noted.Caused by Inadequate Work Practices.Training Session Was Held with Personnel.With 981027 Ltr ML17284A7561998-09-0303 September 1998 LER 98-013-00:on 980805,ESF Actuations Were Noted Due to Deenergization of Vital Electrical Bus SM-8.Caused by Inadequate Direction in Troubleshooting Plan.Will Conduct Training for Engineering Personnel.With 980903 Ltr ML17284A7571998-09-0202 September 1998 LER 98-014-00:on 980807,completion of TS 3.8.1.F Required Shutdown Due to Inoperability of EDG-2 Was Noted.Caused by Degraded Voltage Regulator for DG-2.Replaced Voltage Regulator & Associated Scrs.With 980902 Ltr ML17284A7551998-09-0202 September 1998 LER 98-015-00:on 980808,discovered Reactor Coolant Pressure Boundary Leak During Shutdown Conditions.Caused by Leakage from Socket Weld (Fwb 63) on Elbow Connection.Failed Piping Connection Was Replaced.With 980902 Ltr ML17284A7311998-08-17017 August 1998 LER 98-012-00:on 980716,determined That 24-month SR 3.8.4.7 Had Not Been Fulfilled within Specified Frequency.Caused by Inadequate Work Practices.License Requested & Received Enforcement Discretion Re Battery Svc test.W/980817 Ltr ML17284A7121998-07-23023 July 1998 LER 98-006-01:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of 10CFR50,App R Calculations for High Impedance Faults.Caused by Inadequate Work Practices.Implemented Procedural Changes ML17284A6951998-07-17017 July 1998 LER 98-011-00:on 980617,ECCS Pump Room Flooding Was Noted Due to FP Sys Pipe Break.Caused by Inadequate Design of FP Sys.Detailed Review of FP Sys Design Was Conducted. W/980717 Ltr ML17284A6961998-07-15015 July 1998 LER 98-010-00:on 980615,TS Required Shutdown Due to Inoperability of TIP Sys Isolation Valve Was Noted.Caused by Improper Installation of TIP Tubing.Reattached Affected Tubing & Inspected Other TIP tubing.W/980715 Ltr ML17284A6731998-07-0101 July 1998 LER 98-009-00:on 980606,nuclear Steam Supply Shutoff Sys Group 3 & 4 Isolations During Testing Was Noted.Caused by Procedural Deficiency.Counseled Individuals Involved in preparation.W/980701 Ltr ML17284A6651998-06-24024 June 1998 LER 98-007-00:on 980530,inadvertent Full Scram & Division 1 ECCS Injection Was Noted.Caused by Failure to Meet Mgt Work Practice Expectation When Encountering Deficient Procedure. Incident Review Board Convened to Review event.W/980624 Ltr ML17284A6641998-06-24024 June 1998 LER 98-008-00:on 980531,inadvertent Full Scram During RPV Leak Testing in Mode 4 Was Noted.Caused by Change in Mgt Techniques.Revised Procedures to Take Into Account Addl Water Head in Pressure Sensing lines.W/980624 Ltr ML17284A6631998-06-19019 June 1998 LER 98-006-00:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of App R Calculations for High Impedance Fault Analysis.Caused Indeterminate. Implemented Procedural Changes Involving Operator Action ML17284A6551998-06-0404 June 1998 LER 98-005-00:on 980506,potential for Failure of RHR Sys Valve to Close on Isolation Signal Was Noted.Caused by Design Deficiency.Caution Tag Was Placed on RHR-V-40 Control Switch to Inform Plant Operators of limitation.W/980604 Ltr ML17284A6421998-06-0101 June 1998 LER 98-004-00:on 980502,determined That Primary Containment Penetration Overcurrent Protection Does Not Meet Reg Guide 1.63 Requirements.Caused by Inadequate Design Changes. Installed Addl Fuse in RHR-MO-9 circuit.W/980601 Ltr ML17292B3281998-04-0909 April 1998 LER 98-002-00:on 980311,reactor Scram & Plant Transient Occurred,Due to Failed Closed Main Steam Isolation Valve. Caused by Loss of Pneumatic Actuating Supply Pressure. Problem Evaluation Request Written for Failure of MS-V-22D ML17292B3291998-04-0909 April 1998 LER 98-003-00:on 980311,WNP-2 Experienced SCRAM Signal as Result of Low Rpv.Caused by Less than post-SCRAM Operational Strategy for Resetting SCRAM Signal in Conditions.Changes in post-SCRAM Operational Strategy implemented.W/980409 Ltr ML17292B2661998-03-0404 March 1998 LER 98-001-00:on 980203,automatic Start of HPCS EDG Was Noted.Caused by Operator Error.Operations Crew Stabilized Plant at Approximately 75% Reactor Power & Investigation of Event Was initiated.W/980304 Ltr ML17292B1111997-11-10010 November 1997 LER 97-011-00:on 971010,HPCS Battery Charger Failed.Caused by Failure of a Phase Firing Control Circuit Board Due to Aging During 7 Yrs of Use.Hpcs Sys Was Immediately Declared inoperable.W/971110 Ltr ML17292B1151997-11-0707 November 1997 LER 97-010-00:on 970906,discovered That TS SR 3.4.5.1 for Identified Portion of RCS Total Leakage Would Not Be Able to Perform within Time Limits of SR 3.0.2.Caused by Inadequate Methods.Method of Meeting SR 3.4.5.1 Established ML17292B0641997-09-24024 September 1997 LER 97-004-01:on 970327,plant Operators Manually Scrammed Reactor as Required by TS Due to Indication of Entry Into Region a of power-to-flow Map.Caused by Inadequate Attention to Detail.Established Event Evaluation teams.W/970924 Ltr ML17292B0241997-08-18018 August 1997 LER 97-009-00:on 970717,discovered Error in Recently Performed Inservice Testing procedure,OSP-TIP/IST-R701. Caused by Procedure Inadequacy.Plant Procedure OSP/TIP/IST-R701 Will Be changed.W/970818 Ltr ML17292B0291997-08-15015 August 1997 LER 97-008-00:on 970716,wire Seal Used to Lock Containment Instrument Air Pressure Control valve,CIA-PCV-2B,found Not Intact.Cause of Misadjustment of CIA-PCV-2B Unknown.Event Will Be Communicated to Plant employees.W/970815 Ltr ML17292B0201997-08-15015 August 1997 LER 97-S01-00:on 970718,failure to Take Compensatory Measure for Inoperative Microwave Security Zone Occurred. Caused by Personnel Error.Training Will Be Conducted W/ Appropriate Members of Security force.W/970815 Ltr ML17292A9481997-07-23023 July 1997 LER 97-007-00:on 970611,voluntary Rept of Automatic Start of DG-1 & DG-2 Was Experienced.Caused by Undervoltage Condition on Electrical Busses SM-7 & SM-8.Circulating Water Pump CW-P-1C Control Switch Placed in pull-to-lock.W/970723 Ltr ML17292A9201997-06-26026 June 1997 LER 97-006-00:on 970527,non-performance of Surveillance Requirement 3.6.1.3.2 for Blind Fanges,Was Noted.Caused Because Misunderstanding of Intent of Specs.Added Five Structural Assemblies for SP.W/970626 Ltr ML17292A8331997-04-28028 April 1997 LER 97-004-00:on 970327,plant Operators Manually Scrammed Reactor as Required by TS Due to Entry Into Region a of power-to-flow Map Following Planned Trip of Single Mfp. Event Evaluation teams,established.W/970428 Ltr ML17292A8311997-04-28028 April 1997 LER 97-005-00:on 970327,valid Reactor Scram Signal Received Due to Low Water Level Condition During Preparations for SRV Testing.Caused by Risks & Consequences of Decisions Not Completely Identified.Restored Water level.W/970428 Ltr ML17292A8251997-04-21021 April 1997 LER 97-003-00:on 970320,notification of Noncompliance W/Ts as TS SRs for Response Time Testing Were Not Being Met for Specified Instrumentation in Rps,Pcis & Eccs.Requested Enforcement Discretion for One Time exemption.W/970421 Ltr ML17292A7431997-03-20020 March 1997 LER 97-002-00:on 970218,determined That Rod Block Monitor (RBM) Calibr Values Were Not Set IAW Tech Specs.Caused by Calibr Procedures Inadequacies.Revised & re-performed RBM Channel Calibr procedures.W/970330 Ltr ML17292A7401997-03-13013 March 1997 LER 97-001-00:on 970211,reactor Water Cleanup Sys Blowdown Flow Isolation Setpoint Was Slightly Above TS Allowable Valve Occurred Due to Calculation Error.Lds Fss LD-FS-15 LD-FS-16 Were Declared inoperable.W/970313 Ltr ML17292A6641997-01-22022 January 1997 LER 96-009-00:on 961220,miscalculation of Instantaneous Overcurrent Relay Settings Resulted in Inoperability of safety-related Equipment.Caused by Utilization of Inappropriate Design.Testing Was completed.W/970122 Ltr ML17292A6461997-01-0606 January 1997 LER 96-008-00:on 961205,failure to Comply with TS Action Requirement for Emergency Core Cooling Sys Actuation Instrumentation Occurred Due to Unidentified Inoperability Condition.Pmr initiated.W/970106 Ltr ML17292A6371996-12-19019 December 1996 LER 96-007-00:on 961122,electrical Breakers Were Not Seismically Qualified in Test/Disconnect Position.Circuit Breaker Mfg Did Not Consider Raced Out Breaker Position During Testing.Relocated Circuit breakers.W/961217 Ltr ML17292A4121996-08-0808 August 1996 LER 96-006-00:on 960709,average Power Range Monitor Rod Block Downscale Surveillance Not Performed Prior to Entry Into Mode 1.Caused by long-standing Misinterpretation of Requirements of Tss.Procedures revised.W/960808 Ltr ML17292A3801996-07-24024 July 1996 LER 96-004-00:on 960624,plant Was Manually Scrammed by Control Room Personnel Due to Reactor Water Level Transient Experienced During Testing of Digital Feedwater Sys.Caused by Programming Error.Sys Was corrected.W/960724 Ltr ML17292A3771996-07-24024 July 1996 LER 96-005-00:on 960624,determined Missed Surveillance Test Re Channel Check of Average Power Range Monitor.Caused by Inadequate Procedures.Revised Surveillance Procedure Re When APRM Checks Must Be performed.W/960724 Ltr ML17292A3641996-07-12012 July 1996 LER 96-003-00:on 960615,required Surveillance Test Not Performed When Required by TS 3.4.1.3.Caused by Inadequate Procedures.Implementing Surveillance Procedure & Reactor Plant Startup Procedures revised.W/960712 Ltr ML17292A3361996-06-20020 June 1996 LER 96-002-00:on 960504,critical Bus SM-8 Lost Power When Supply Breaker 3-8 Tripped.Caused by Personnel Error. Operators Counselled & Procedures revised.W/960620 Ltr ML17292A2861996-05-24024 May 1996 LER 96-001-00:on 960425,inadvertent ESF Actuations Occurred Due to Tripping of Temporary Power Supply to IN-3.Caused by Personnel Error.Operations Restored to IN-3 Loads & Reset ESF actuations.W/960524 Ltr ML17291B0891995-10-19019 October 1995 LER 95-011-00:on 950919,failed to Comply W/Ts SR for RCIC Sys Due to Analysis Deficiency That Resulted in Inadequate Surveillance Test Procedure.Surveillance Procedure Revised to Correct deficiency.W/951019 Ltr ML17291A9021995-07-0707 July 1995 LER 95-010-00:on 950609,HPCS DG Declared Inoperable Due to Discovery That TS Test Method Incomplete.Caused by Inadequate Testing Procedure.Test Procedure for HPCS DG Reviewed & Special Test Procedures written.W/950707 Ltr ML17291A9031995-07-0707 July 1995 LER 95-009-00:on 950607,inadvertent MSIV Closure Occurred During Surveillance Test Due to Poor Communication Between Test Team.Determined That MSIV Closure Not Valid Because Closure Not Triggered by Plant conditions.W/950707 Ltr ML17291A8501995-06-0808 June 1995 LER 95-006-01:on 950405,reactor Scram Occurred During Surveillance Testing Due to Protective Sys Relay Failure. Replaced Failed Relay Before Plant Startup ML17291A8101995-05-12012 May 1995 LER 95-008-00:on 940125,TS Wording Lead to Potential TS Violation.Caused by Lack of Clarity in Ts.Submitted Improved TS for Plant to Provide Addl clarity.W/950512 Ltr ML17291A7841995-05-0505 May 1995 LER 95-007-00:on 950222,emergency Diesel Start Occurred Due to Voltage Transient on BPA Grid.Confirmation Was Received at 17:51 H That Disturbance Had Originated in BPA Grid ML17291A7801995-05-0404 May 1995 LER 95-006-00:on 950405,main Turbine Trip Occurred During Performance of Surveillance Test Due to Protective Sys Relay Failed.Replaced Failed Relay Before Plant startup.W/950504 Ltr ML17291A7851995-05-0303 May 1995 LER 95-005-00:on 950222,inoperable IRM Had Been Relied Upon to Meet TS Requirements During Reactor Startup.Caused by Lack of Neutron Source to Test Instrumentation. Sys Knowledge Gained Will Be incorporated.W/950503 Ltr ML17291A7071995-03-25025 March 1995 LER 95-004-00:on 950226,malfunction in Main Turbine DEH Control Sys Caused All Four High Pressure Turbine Governor Valves to Rapidly Close.Caused by Blown Fuse.Suspected Faulty Circuit Card replaced.W/950325 Ltr ML17291A7011995-03-20020 March 1995 LER 95-002-00:on 950218,automatic Reactor Scram Occurred. Caused by Erroneous Positioning of Control During Performance of Scheduled Periodic Functional Test.Control repositioned.W/950320 Ltr 1999-07-20
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML17284A9001999-10-31031 October 1999 Rev 0 to COLR 99-15, WNP-2 Cycle 15,COLR GO2-99-177, LER 99-S01-00:on 990903,failure to Take Compensatory Measure within Required Time Upon Failure of Isolation Zone Microwave Unit,Was Noted.Caused by Personnel Error.Provided Refresher Training on Compensatory Measures.With1999-10-0101 October 1999 LER 99-S01-00:on 990903,failure to Take Compensatory Measure within Required Time Upon Failure of Isolation Zone Microwave Unit,Was Noted.Caused by Personnel Error.Provided Refresher Training on Compensatory Measures.With ML17284A8941999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for WNP-2.With 991012 Ltr ML17284A8801999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for WNP-2.With 990910 Ltr ML17284A8691999-07-31031 July 1999 Monthly Operating Rept for July 1999 for WNP-2.With 990813 Ltr ML17292B7421999-07-20020 July 1999 LER 99-001-00:on 990628,ESF Signal Closed All Eight MSIVs While Plant Was Shutdown.Caused by Failure of Relay RPS-RLY-K10D.Subject Relay Was Replaced & Tested on 990630. with 990720 Ltr ML17292B7271999-06-30030 June 1999 Monthly Operating Rept for June 1999 for WNP-2.With 990707 Ltr ML17292B6961999-05-31031 May 1999 Monthly Operating Repts for May 1999 for WNP-2.With 990608 Ltr ML17292B6641999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for WNP-2.With 990507 Ltr ML17292B6391999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for WNP-2.With 990413 Ltr ML17292B5871999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for WNP-2.With 990311 Ltr ML17292B5571999-01-31031 January 1999 Monthly Operating Rept for Jan 1999 for WNP-2.With 990210 Ltr ML17292B5621999-01-31031 January 1999 Rev 1 to COLR 98-14, WNP-2 Cycle 14 Colr. ML17292B5341999-01-15015 January 1999 Part 21 Rept Re Incorrect Modeling of BWR Lower Plenum Vol in Bison.Defect Applies Only to Reload Fuel Assemblies Currently in Operation at WNP-2.BISON Code Model for WNP-2 Has Been Revised to Correct Error ML17292B5331999-01-15015 January 1999 Part 21 Rept Re XL-S96 CPR Correlation for SVEA-96 Fuel. Defect Applies Only to WNP-2,during Cycles 12,13 & 14 Operation.Evaluations of Defect Performed by ABB-CE ML17292B4791998-12-31031 December 1998 Washington Public Power Supply Sys 1998 Annual Rept. with 981215 Ltr ML17292B5351998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for WNP-2.With 990112 Ltr ML17292B5741998-12-31031 December 1998 WNP-2 1998 Annual Operating Rept. with 990225 Ltr ML17284A8231998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for WNP-2.With 981207 Ltr ML17284A8081998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for WNP-2.With 981110 Ltr ML17292B4451998-10-27027 October 1998 LER 98-012-01:on 980715,failure to Comply with Requirements of TS SR 3.8.4.7 Was Noted.Caused by Inadequate Work Practices.Training Session Was Held with Personnel.With 981027 Ltr ML17284A7831998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for WNP-2.With 981007 Ltr ML17284A7491998-09-10010 September 1998 WNP-2 Inservice Insp Summary Rept for Refueling Outage RF13 Spring,1998. ML17284A7561998-09-0303 September 1998 LER 98-013-00:on 980805,ESF Actuations Were Noted Due to Deenergization of Vital Electrical Bus SM-8.Caused by Inadequate Direction in Troubleshooting Plan.Will Conduct Training for Engineering Personnel.With 980903 Ltr ML17284A7571998-09-0202 September 1998 LER 98-014-00:on 980807,completion of TS 3.8.1.F Required Shutdown Due to Inoperability of EDG-2 Was Noted.Caused by Degraded Voltage Regulator for DG-2.Replaced Voltage Regulator & Associated Scrs.With 980902 Ltr ML17284A7551998-09-0202 September 1998 LER 98-015-00:on 980808,discovered Reactor Coolant Pressure Boundary Leak During Shutdown Conditions.Caused by Leakage from Socket Weld (Fwb 63) on Elbow Connection.Failed Piping Connection Was Replaced.With 980902 Ltr ML17284A7681998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for WNP-2.With 980915 Ltr ML17284A7311998-08-17017 August 1998 LER 98-012-00:on 980716,determined That 24-month SR 3.8.4.7 Had Not Been Fulfilled within Specified Frequency.Caused by Inadequate Work Practices.License Requested & Received Enforcement Discretion Re Battery Svc test.W/980817 Ltr ML17284A7261998-07-31031 July 1998 Monthly Operating Rept for July 1998 for WNP-2.W/980810 Ltr ML17284A7121998-07-23023 July 1998 LER 98-006-01:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of 10CFR50,App R Calculations for High Impedance Faults.Caused by Inadequate Work Practices.Implemented Procedural Changes ML17284A6951998-07-17017 July 1998 LER 98-011-00:on 980617,ECCS Pump Room Flooding Was Noted Due to FP Sys Pipe Break.Caused by Inadequate Design of FP Sys.Detailed Review of FP Sys Design Was Conducted. W/980717 Ltr ML17284A6961998-07-15015 July 1998 LER 98-010-00:on 980615,TS Required Shutdown Due to Inoperability of TIP Sys Isolation Valve Was Noted.Caused by Improper Installation of TIP Tubing.Reattached Affected Tubing & Inspected Other TIP tubing.W/980715 Ltr ML17284A6731998-07-0101 July 1998 LER 98-009-00:on 980606,nuclear Steam Supply Shutoff Sys Group 3 & 4 Isolations During Testing Was Noted.Caused by Procedural Deficiency.Counseled Individuals Involved in preparation.W/980701 Ltr ML17284A6751998-06-30030 June 1998 Ro:On 980617,flooding of RB Northeast Stairwell with Consequential Flooding of Two ECCS Pump Rooms.Caused by Inadequate Fire Protection Sys Design.Pumped Out Water from Affected Areas to Point Below Berm Areas of Pump Rooms ML17284A6641998-06-24024 June 1998 LER 98-008-00:on 980531,inadvertent Full Scram During RPV Leak Testing in Mode 4 Was Noted.Caused by Change in Mgt Techniques.Revised Procedures to Take Into Account Addl Water Head in Pressure Sensing lines.W/980624 Ltr ML17284A6651998-06-24024 June 1998 LER 98-007-00:on 980530,inadvertent Full Scram & Division 1 ECCS Injection Was Noted.Caused by Failure to Meet Mgt Work Practice Expectation When Encountering Deficient Procedure. Incident Review Board Convened to Review event.W/980624 Ltr ML17284A6631998-06-19019 June 1998 LER 98-006-00:on 980520,discovered Discrepancies in Low Voltage Bus Calculations During Review of App R Calculations for High Impedance Fault Analysis.Caused Indeterminate. Implemented Procedural Changes Involving Operator Action ML17284A6551998-06-0404 June 1998 LER 98-005-00:on 980506,potential for Failure of RHR Sys Valve to Close on Isolation Signal Was Noted.Caused by Design Deficiency.Caution Tag Was Placed on RHR-V-40 Control Switch to Inform Plant Operators of limitation.W/980604 Ltr ML17284A6421998-06-0101 June 1998 LER 98-004-00:on 980502,determined That Primary Containment Penetration Overcurrent Protection Does Not Meet Reg Guide 1.63 Requirements.Caused by Inadequate Design Changes. Installed Addl Fuse in RHR-MO-9 circuit.W/980601 Ltr ML17284A6491998-05-31031 May 1998 Rev 0 to COLR 98-14, WNP-2,Cycle 14 Colr. ML17292B4031998-05-31031 May 1998 Monthly Operating Rept for May 1998 for WNP-2.W/980608 Ltr ML17292B3921998-04-30030 April 1998 Monthly Operating Rept for Apr 1998 for WNP-2.W/980513 Ltr ML17292B3291998-04-0909 April 1998 LER 98-003-00:on 980311,WNP-2 Experienced SCRAM Signal as Result of Low Rpv.Caused by Less than post-SCRAM Operational Strategy for Resetting SCRAM Signal in Conditions.Changes in post-SCRAM Operational Strategy implemented.W/980409 Ltr ML17292B3281998-04-0909 April 1998 LER 98-002-00:on 980311,reactor Scram & Plant Transient Occurred,Due to Failed Closed Main Steam Isolation Valve. Caused by Loss of Pneumatic Actuating Supply Pressure. Problem Evaluation Request Written for Failure of MS-V-22D ML17292B3371998-03-31031 March 1998 Monthly Operating Rept for Mar 1998 for WNP-2.W/980409 Ltr ML17292B2641998-03-0404 March 1998 Performance Self Assessment,WNP-2. ML17292B2661998-03-0404 March 1998 LER 98-001-00:on 980203,automatic Start of HPCS EDG Was Noted.Caused by Operator Error.Operations Crew Stabilized Plant at Approximately 75% Reactor Power & Investigation of Event Was initiated.W/980304 Ltr ML17292B2911998-02-28028 February 1998 Monthly Operating Rept for Feb 1998 for WNP-2.W/980313 Ltr ML17284A7971998-02-17017 February 1998 Rev 28 to Operational QA Program Description, WPPSS-QA-004.With Proposed Rev 29 ML17292B3591998-02-12012 February 1998 WNP-2 Cycle 14 Reload Design Rept. 1999-09-30
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ACCELERATE DOCUIVIENT DISTRIBUTION SYSTEM REGULARLY INFORMATION DISTRIBUTIO YSTEM (RIDS)ACCESSION NBR:9302220096 DOC.DATE: 93/02/12 NOTARIZED:
NO DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2 Washington Public Powe 05000397 AUTH.NAME AUTHOR AFFILIATION FIESPC.L.Washington Public Power Supply System BAKER,J.W.
Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION
SUBJECT:
LER 88-031-01:on 880902,determined that due to single failure CR HVAC sys could operate in recirculation mode.Caused by lack of communication between AE design groups.CR HVAC recirculation mode of operation analyzed.W/930212 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR j ENCL j SIZE: C TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: D RECIPIENT ID CODE/NAME PD5 LA CLIFFORDPJ INTERNAL: ACNW AEOD/DOA AEOD/ROAB/DSP NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D D SPLB8D1 EG FIL 02 RGN5 FILE 01 EXTERNAL: EGGG BRYCE,J.H NRC PDR NSIC POOREPW COPIES LTTR ENCL 1 1 1 1 2 2 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 2 2 1 1 1 1 RECIPIENT ID CODE/NAME PD5 PD ACRS AEOD/DSP/TPAB NRR/DET/EMEB 7E NRR/DLPQ/LPEB10 NRR/DREP/PRPBll NRR/DST/SICB8H3 NRR/DST/SRXB 8E RES/DSIR/EIB L ST LOBBY WARD NSIC MURPHYPG.A NUDOCS FULL TXT COPIES LTTR ENCL 1 1 2 2 1 1 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 D D D D NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP VS TO REDUCE WASTEI CONTACT THE DOCVMENT CONTROL DESK, ROOM Pl-37 (EXT.504-2065)TO ELIMINATE YOVR NAME FROM DISTRIBVTION LISTS FOR DOCUMENTS YOV DONT NEEDl D S FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 31 ENCL 31 vi WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O.Box 968~3000 George Washington Way~Richland, Washington 99352 February 12, 1993 G02-93-032 Docket No.50-397 Document Control Desk U.S.Nuclear Regulatory Commission Washington, D.C.20555
SUBJECT:
NUCLEAR PLANT WNP-2, OPERATING LICENSE NPF-21 LICENSEE EVENT REPORT NO.88-031-01 Transmitted herewith is Licensee Event Report No.88-031-01 for the WNP-2 Plant.This revised report is submitted in response to the requirements of 10CFR50.73.
It provides an update of the corrective actions and an evaluation of the safety significance that was not available for the original report.Sincerely, J.W.Baker WNP-2 Plant Manager (Mail Drop 927M)JWB/CLF/my 901.24 CC: Mr.J.B.Martin, NRC-Region V Mr.R.Barr, NRC Resident Inspector (Mail Drop 901A, 2 Copies)INPO Records Center-Atlanta, GA Mr.D.L.Williams, BPA (Mail Drop 399)9302220096 930212 PDR ADOCK 05000397 S PDR LICENSEE EV T REPORT (LER)ACILITY NAME (I)Washin ton Nuclear Plant-Unit 2 DOCKET HUMB R ()PAGE (3)0 5 0 0 0 3 9 7 I DF 7 TITLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROOM HVAC TO OPERATE IN AN UNANALYZED OPERATION MODE DUE TO DESIGN EVENT DATE (5)MONTH DAY YEAR YEAR LER NUMBER SEQUENTIAL NUMBER 6)EV I SION UMBER REPORT DATE (7)YEAR DAY MONTH OTHER FACILITIES INVOLVED (8)CKET 00 FACILITY NAMES HUMBE RS(S)0 9 0 2 8 8 8 8 0 3 1 0 I 0 2 I 2 9 3 5 0 050 PERATING ODE (9)HIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 5: (Check one or more of the following)
(11)4 ONER LEVEL (10)0 0 0 20.402(b)20.405(a)(1)(i) 20.405(a)(1)(ii) 20.405(a)(1)(iii) 20.405(a)(1)(iv) 0.405(a)(1)(v) 20.405(C)50.36(c)(1) 50.36(c)(2) 50.73(a)(2)(i)
X 50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50.73(a)(2)(viii)(A) 50.73(a)(2)(viii)(B) 50.73(a)(2)(x) 77.71(b)73.73(c)THER (Specify in Abstract clew and in Text, NRC orm 366A)NAME LICENSEE CONTACT FOR THIS LER (12)C.L.Fies, Licensing Engineer TELEPHOHE NUMBER REA CODE 5 0 9 7 7-4 1 4 7 COMPLETE OHE LINE FOR EACH COMPONENT FAILURE DESCRIBED IH THIS REPORT (13)CAUSE SYSTEM COMPONENT MAHUFACTURER EPORTABLE 0 HPRDS CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPRDS 2;l,.'UPPLEMENTAL REPORT EXPECTED (14)YES (If es c iete EXPECTED SUBMISSIOH DATE)NO TAACT OOI EXPEC'TED SUBMISSION MONTH DAY YEAR ATE (15)On September 2, 1988, a Design Engineer determined that due to a single failure the Control Room Heating and Ventilation (HVAC)System could operate in the recirculation mode during emergency conditions.
This unanalyzed condition was found while performing an engineering evaluation of the safety significance of the event reported in LER 88-005-00.
During a Loss of Coolant Accident (LOCA)the normal fresh air intake for the Control Room HVAC is isolated and two remote air intake lines are opened.Each remote air intake line has two isolation valves and one valve is powered from Division 1 and the other from Division 2.A single failure (not a loss of power failure)in a power division could cause a valve in each remote air intake line to isolate.With the loss of all fresh air input the Control Room HVAC would continue to operate but in the recirculation mode.In the recirculation mode the Control Room would not remain pressurized with respect to surrounding areas, and operating post LOCA in this mode was not an analyzed condition.
Immediate corrective actions were: The motor operators for the four (two per line)remote air intake isolation valves were replaced with manual operators.
Two of the four.radiation purge line isolation valves motor operators were electrically disconnected.
Both isolation valves in the remote intake lines were locked open to assure that a single failure could not result in recirculation mode operation.
The Control Room Emergency Filtration System was started and the Control Room HVAC System is operating in the pressurization mode.
LICENSEE EVENT REPOR ER)TEXT CONTINUATION AGILITY NAME (1)Washington Nuclear Plant-Unit 2 DOCKET NUMBER (2)LER NUMBER (8)ear umber ev.No.AGE (3)8 3 1 1 2 OF 7 TiTLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROON HVAC TO OPERATE IN AN UNANALYZED OPERATION NODE DUE TO DESIGN Ab tract nt'd The cause of this event was the Plant Architect/Engineer (AE)did not provide a Control Room HVAC System design which protected the system against all possible single failures.The root cause of this event is a lack of communication between AE design groups.Further corrective actions were taken: The Control Room HVAC recirculation mode of operation was analyzed.Technical Specification Amendment No.74 was received allowing Control Room HVAC operation with the revised configuration.
A letter was sent to Burns&Roe Inc.providing notification of a potential 10CFR Part 21 condition.
PI n Con i ion Power Level-0%Plant Mode-4 (Cold Shutdown)Event De ri ti n On September 2, 1988, a Design Engineer determined that, due to single failures, the Control Room Heating and Ventilation (HVAC)System could operate during emergency conditions in the recirculation mode, which is an unanalyzed condition.
This unanalyzed condition was discovered while performing an engineering evaluation committed to in LER 88-005-00 to evaluate the potential effects of minor Control Room HVAC system changes on system bypass flow.The following brief description of the Control Room HVAC System (before modification) for normal operation and emergency operation during a Loss of Coolant Accident (LOCA)is presented to aid in understanding the event and the changes made to the system.Figure 1 is a partial diagram of the Control Room HVAC System prior to the event.The Control Room HVAC System consists of two redundant systems for both normal and emergency operation.
During normal operation, 1000 cfm of fresh air from the normal roof intake Radwaste Building is mixed with 20,000 cfm of recirculated air (through fan 51A or 51B).Seven hundred and fifty (750)cfm is exhausted from the control room through fan 51 and the remaining 250 cfm pressurizes the control room and is exfiltrated.
Also during normal operation, the remote air intake isolation valves (51A and B and 52A and B)are closed and the radiation monitor purge line valves (51D and E and 52D and E)are open with radiation monitor purge line fans 53A and B operating.
During a LOCA when any of the following trip levels are reached 1)High drywell pressure ("F" signal), 2)Low low reactor water level ("A" signal)or 3)Reactor building ventilation exhaust high radiation ("Z" signal)the following actions occur: a)The normal roof intake Radwaste Building is isolated by closing valves 51C and 52C.
LICENSEE EVENT REPOR LER)TEXT CONTINUATION AGILITY NAME (1)Washington Nuclear Plant-Unit 2 I OOCKET NUMBER (2)0 5 0 0 0 3 9 7 ev.No.8 031 01 LER NUMBER (B)ear umber AGE (3)3 F 7 1TLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROOM HVAC TO OPERATE IN AN UNANALYZED OPERATION MODE, DUE TO DESIGN b)The 750 cfm control room exhaust fan (51)deenergizes.
c)The remote air intake isolation valves (51A, 51B, 52A, and 52B)open and the radiation monitor purge line isolation valves (51D, 51E, 52D and 52E)close.The remote air intake isolation valves and the radiation monitor purge line isolation valves are interlocked so when an intake line is opened the associated purge line is isolated.d)The control room emergency filtration system is automatically started and draws 1000 cfm of fresh air through the remote air intakes.This additional air, when added to the recirculated air, pressurizes the control room.The event described in LER 88-005 was for leakage around the emergency filters in excess of the technical specification allowable limit.During the engineering evaluation committed to in LER 88-005 to determine the effect of the excess leakage on control room habitability, a design engineer determined that postulated single failures could cause some combination of remote air intake line isolation valves to fail to open or to reisolate and;thus, isolate both remote air intake lines.If this condition existed during LOCA conditions, the Control Room HVAC would be running in a recirculation mode only since the normal roof intake is also isolated.In the recirculation mode the 20,000 cfm would continue to be drawn from the control room and recirculated back to the control room;however, without the fresh air input the control room would not be pressurized.
In a neutral pressure condition the inleakage to the control room would increase and this condition is not analyzed.Imm iateAci n The planned Plant Startup was delayed until the following actions were completed.
1)The motor operators were removed and manual operators were installed on the remote air intake isolation valves (51A and B and 52A and B).The valve operators were changed to manual so the isolation valves on the remote intake lines could be opened without an FAZ signal present;thereby, assuring that a single failure could not cause operation in the recirculation mode.With the remote air intake lines open, the control room emergency filtration system is started, fan 51 is deenergized, and the associated damper is closed.This put the Control Room HVAC system in the pressurization mode of operation which satisfied the action statement of Technical Specification 3.3.7.1.The current Plant configuration has both remote intakes open during normal operation.
Figure 2 shows the post event Control Room HVAC configuration.
2)Two of the radiation purge line isolation valve electro-pneumatic operator motors (52D and 51E)were electrically disconnected which causes the valves to open.This was done so that only one manual action is required to isolate a remote path and cause the associated purge path to open or vice versa.3)The 750 cfm control room exhaust fan (51)was deenergized.
4)Specific directions for Plant Operators to execute to maintain design bases in the event of a LOCA were provided in (approved) deviated Plant procedures.
Each new operations crew was provided training by Operation Managers.
LICENSEE EVENT REPOR LER)TEXT CONTINUATION AGILITY NAHE (I)Washington Nuclear Plant-Unit 2 00CKET NUHBER (2)0 5 0 0 0 3 9 7 Year LER NUHBER (8)umber ev.No.AGE (3)8 031 01 4 F 7 TITLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROOM HVAC TO OPERATE IN AN UNANALYZED OPERATION MODE DUE TO DESIGN Further Evaluati n and orrective Action A.Further Evaluation This event was reported per 10CFR50.72(b)(2)(i) on September 2, 1988 at 1702 hours0.0197 days <br />0.473 hours <br />0.00281 weeks <br />6.47611e-4 months <br />.The event is also reported per 10CFR50.73(a)(2)(ii)(A).
There were no structures, systems, or components inoperable prior to this event which contributed to the event.The cause of this event was the failure of the Plant Architect/Engineer (Burns&Roe Inc.)to provide a system design for which a single failure could not isolate both remote air intakes and cause the Control Room HVAC System to operate in the recirculation mode, or to analyze the recirculation mode of operation.
The root cause of this event is a lack of communication between the Architect/Engineer design groups.B.Further Corrective Action 1)The Control Room HVAC recirculation mode of operation was analyzed.The results are summarized under safety significance below.2)Technical Specification Amendment 74 was received allowing operation of the Control Room HVAC system in the revised configuration.
3)A letter was sent to Burns&Roe Inc., providing notification of a potential 10CFR Part 21 condition.
~Sf ii lit~i The safety significance of operation in the recirculation mode has been evaluated.
The results are documented in Technical Memorandum TM-1158, Revision 4.The calculation assumed Control Room inleakage in the range of 350 to 450 cubic feet per minute.The calculated whole body gamma dose and skin beta dose were within limits.However, the calculated thyroid dose was approximately 100 Rem which exceeds the Standard Review Plan 6.4 limit of 30 Rem.It is therefore concluded that this event has safety significance as a single failure during LOCA conditions could have resulted in Licensing Basis Document (LBD)limits being exceeded.imil r Ev n None LICENSEE EVENT REPOR ER)TEXT CONTINUATION AGILITY NAME (1)Washington Nuclear Plant-Unit 2 OOCKET NUMBER (2)0 5 0 0 0 3 9 7 LER NUMBER (8)ear'(umber ev.No.8 031 01 AGE (3)5 OF 7 ITLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROOM HVAC TO OPERATE IN AN UNANALYZED OPERATION MODE DUE TO DESIGN E~f Tex R f ren f*/~Lcm m~mm~nen Control Room Heating and Ventilation (HVAC)System Normal Fresh Air Intake (Normal Roof Intake Radwaste Building)Remote Air Intake Line, (East or West)Remote Air Intake Isolation Valves (51A and B and 52A and B)Remote Air Intake Isolation Valve Motor Operator (Electro-Pneumatic Motor Operator)Radiation Purge Line Isolation Valves (51D and E and 52D and E)Radiation Purge Line Isolation Valve Motor Operator (Electro-Pneumatic Motor Operators)
Control Room Emergency Filtration System Fan 51A or 51B 750 cfm Control Room Exhaust Fan (51)Radiation Purge Live Exhaust Fans (53A and B)VH VH VH VH VH VH VH ISV 84 ISV 84 FAN FAN FAN LICENSEE EVENT REPOR ER)TEXT CONTINUATION AGILITY HAHE (I)Washington Nuclear Plant-Unit 2 OOCKET HUHBER (2)0 5 0 0 0 3 9 7 LER HUHBER (8)ear umber ev.Ho.8 031 1 AGE (3)6 F 7 ITLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROON HVAC TO OPERATE IN AN UNANALYZED OPERATION NODE DUE TO DESIGN I RCHOTE INTAKC I I 01 I L Rc IV 11 RC AH TYPICAL , I vhLvcs I'OPQ<OJJ I FAX I I gna>>>>52B 5IB+DJV II I I Dlv I CHER G FILTER II II II II II II'~JI I I I I 0 SIKE 52C DIV ll r-M" 5ZA I FGDIV II EHER6 FILTER I I I I I I L I DIV ll 50B-I Dlv I 5<A-I~5 I A DIV Il I I I I I I I I.r" I I 5IA-I IB"I DIV I V II FAM 50B DIV II FAN 50A DIV I FAN 5IB Dlv 11 FAN 51A Dlv I CONTROL ROON VALVES CLOSC NORHAI ROOF ON HIGH-HJQI INTAKC I RADIATION ALARM RADVASTE VALVES<TYPICAL>BLDG OPEN OW I FAX 0 EHO 5IC DIV I CLOSC OM fAX RLHOTE OITAKC lz<EASTI DIV I RC J RR TYPICAL EHO EHO 0 5ID FO 52DFO DIV I Dlv 11 154 CTH~EHO EHO FO FO Dlv Il DIV'I FC>>fAIL CLOSED FO>>FAlL OPOI NC>>JCRHAl.LY CLOSED NO>>NORMALLY OPEN LO>>LOCKED OPEN LC>>LOCKED CLOSED Q>>ANNNCJATOR 14 RE>>RAD ELEMENT RR>>RAD RECORDER EHO>>ELECTRO HYDRAILIC OPERATOR HAN>>HAJIUAL OPERATOR FAH 53A'AH 53B DIV I DIV II PURGE CKJJAUST FAX>>HJQI DRYVELL PRESSUREJ LOV REACTOR VCSSEL VATER LEVELJ REACTOR BUILDIHG VOITJLATION EKHAUST HIGH RADIATIOK IJJFORHATION DRAVJNG DNLY SEPT 22.1888 954 CFH EXHAUST DEEHERGIXE ON fAX FAH 51lI'AOIQKGToN Pvouo PoYKA 43 SUPPLY SYSTEM'IEtulGL VATHlJJGTOH 993524968 TJTLC ORIGINAL VNP 2 I'ARTJAL CONTROL ROON VENTILATION SYS Figure 1 Pre-Event Control Room HVAC LICENSEE EVENT REPOR ER)TEXT CONTINUATION AGILITY NAHE (1)Washington Nuclear Plant-Unit 2 OOCKET NUHBER (2)0 5 0 0 0 3 9 7 ear LER NUHBER (8)umber ev.No.AGE (3)8 3 I I 7 F 7 ITLE (4)SINGLE FAILURE COULD CAUSE CONTROL ROOM HVAC TO OPERATE IN AN UNANALYZED OPERATION NODE DUE TO DESIGN QRE IV II RKHOTE ItNAKC et WEST>ttAH IRIRttnL Ruof It t IAKC RADVASTC tto Qtto Pf 51C DIV I~FC cLosc ott rnz Hntt HO~Etto 52C DIV II rc DIV Il ste-t FHKRG FILTER HAtl H tIAH l DIV 11)DIV I EIIERG FILTER RQIOTE It t TAKE e2 (EAST)Dlv I RR T YPI CAI.TYPICAL rnu 5th DIV I 5th-I DIV I 31 D-I)V It rnN sic DIV II DKTERN'D El lO FAN 5IA DIV I TAN 51D DIV II cottTRUL Relet DE'TERN'D slo ro Score DIV I DIV II FO523 FO 51 DIV II DIV I LEKIQl FLOV Itl LOIC~Ito FLOV IH LlttE FC>>FAIL CLOSED FO>>I'AIL OPEN IIC>>ttORHALLY CLOSED NO>>IIORHALLY OPEN LO>>LOCKED OPEN LC>>LOCKED CLOSED A,~ntotuttctntoR to RE RAD ELKHEHl'R>>
RAD RECORDER Et to>>ELECTRO IITDRAULIC OPERATOR Hntt>>HAIIUAL OPERA'TOR rntt 53n F'nN 53B DIV I DIV II" PURGE CXIIAUST rnw sl~TSO CFH EXHAUST DELIIERGIZE OH FAZ f'AZ IIIQI DRYMELL PRESSUREI LOV REACTOR VCSSEL VAILR LEVELt REACTOR DUILoltlo vEHTILATIotl ExttnusT IIIQI RADIATIUIL IttreettnttOH DRnvlHG QILY SEPt 27.19oo xtotoxotott rootle ronn b3 svpvu'vsYFw RIEIILAIIIL MASIIIIIGION 99352-0968 1ICLC pRoposKD vtlp 2 pnRtlnL cotttRUL Roott vEttllLATIUtl sts Figure 2 Post-Event Control Room HVAC