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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML18017A9181999-10-0808 October 1999 LER 99-008-00:on 991008,CR Emergency Filtration Sys Tech Specs Occurred.Caused by Site Personnel Failed to Recognize That Blocking Open CR Emergency Filtration Sys.Procedures Revised.With 991008 Ltr ML18017A8671999-09-10010 September 1999 LER 99-007-00:on 990811,determined That Cvis ARMs High Alarm Setpoints Were Not within TS Limit.Caused by Not Having Procedure to Verify If Cvis ARM High Alarm Setpoints Were within TS Requirements.Revised Procedures.With 990910 Ltr ML18016B0481999-08-0404 August 1999 LER 99-006-01:on 981124,noted Failure to Comply with TS 4.0.4 & TS 3/4.6.3, Civs. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Was Revised ML18016A9801999-06-0404 June 1999 LER 99-006-00:on 981124,failed to Comply with TS 4.0.4 & TS 3/4.6.3, Civ. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Will Be Revised.With 990604 Ltr ML18016A9111999-04-12012 April 1999 LER 99-005-00:on 990313,plant Exceeded ESFAS TS 3.3.2,Action 21.Caused by Inadequate Procedure Rev Preparation.Licensee Revised Applicable Maint Surveillance Test Procedure (MST-10072) to Identify TS Required Actions.With 990412 Ltr ML18016A8971999-04-0808 April 1999 LER 99-004-00:on 990312,unit Trip Was Noted.Caused by Degraded Condition of SG Water Level Flow Control Valve. Replaced Positioners on All Three FW Regulating Valves.With 990408 Ltr ML18016A8261999-02-22022 February 1999 LER 99-003-00:on 990123,noted That Plant Was Outside Design Basis Due to Isolation of Fire Protection Containment Sprinkler Sys.Caused by Human Error.Restored Containment Sprinkler Sys to Operable Status.With 990222 Ltr ML18016A8111999-02-12012 February 1999 LER 99-002-00:on 990114,RT Due to Not Removing Temporary Device from Relay Following Calibration Was Noted.Caused by Human Error.Counseled Personnel Involved in Event.With 990212 Ltr ML18016A7971999-02-0505 February 1999 LER 99-001-00:on 990106,SF Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Fasteners Bending Under Specific Circumstances.Increased Water Level.With 990205 Ltr ML18016A7941999-01-29029 January 1999 LER 98-004-01:on 980313,identified Design Deficiency Re Potential Runout of Tdafwp.Caused by Inadequate Original AFW Sys Design.Operability Evaluation Was Completed on 980313 & Addl Engineering Analysis Was Performed by Vendor ML18016A7211998-11-17017 November 1998 LER 98-007-00:on 981023,turbine Control Anomaly Caused Manual Rt.Caused by Failure to Incorporate Verbal Vendor Guidance in Operating Procedures.Addl Vendor Guidance Will Be Verified & Added to Procedures.With 981117 Ltr ML18016A4841998-07-0707 July 1998 LER 97-002-01:on 970207,determined That Cold Weather Conditions Resulted in Mfiv Being Potentially Inoperable During Period 970117-20.Caused by Inadequate Design of HVAC Sys.Implemented Mods to Steam Tunnel HVAC Sys ML18016A4701998-06-30030 June 1998 LER 97-021-03:on 980210,discovered That SFP Water Level Had Not Been Verified Greater than 23 Feet Above BWR Fuel Assemblies.Caused by Misinterpretation of TS Requirements. Will Submit TS Change Request to Revise TS 3.9.1.11 ML18016A4491998-06-0808 June 1998 LER 98-006-00:on 980508,failure to Perform Insp & Preventive Maint on MCCB as Required by TS Was Noted.Caused by Inadequate Sps.Tested 9 Pressurizer Heater Bank Breakers by Cycling each.W/980608 Ltr ML18022B0551998-05-20020 May 1998 LER 98-005-00:on 980420,TS Verbatim non-compliance Was Determined.Caused by Misinterpretation of TS Requirements. Issued Memo to Reemphasize Need to Comply W/Literal Meaning of TS Requirements in Verbatim manner.W/980520 Ltr ML18016A4061998-04-30030 April 1998 LER 98-002-01:on 980121,determined Ssps (P-11 Permissive) Testing Deficiency.Caused by Inadequate Review of Initial Ts.Will Revise & Perform Surveillance Test Procedures to Verify Operability of P-11 Permissive ML18016A3841998-04-13013 April 1998 LER 98-004-00:on 980313,design Deficiency Related to Indequate Runout Protection for Turbine Driven AFW Pump Was Identified.Caused by Inadequate Original AFW Sys Design. Evaluation (ESR 98-00100) Will Be completed.W/980409 Ltr ML18016A3441998-03-12012 March 1998 LER 97-021-02:on 980210,identified Failure to Properly Test non-safety Related Pressurizer Porv.Caused by Inadequate Surveillance Test Procedures.Revised Operations Surveillance Test OST-1117 to Include Testing of Subject PORV ML18016A3291998-02-27027 February 1998 LER 98-003-00:on 980129,failure to Perform Shutdown Margin Calculation Required by TS Surveillance Requirements Occurred.Caused by Ambiguity in TS 3.1.3.1.c.Procedures revised.W/980227 Ltr ML18016A3211998-02-20020 February 1998 LER 98-002-00:on 980121,solid State Protection Sys Testing Deficiency Occurred.Caused by Inadequate Review of Initial Tech Specs.Ts Testing Frequency for P-11 Permissive Revised. W/980217 Ltr ML18016A3131998-02-0909 February 1998 LER 98-001-00:on 980109,potential Condition Outside Design Basis Related to Instrument Air Sys Leak Causing SG pre- Heater Bypass Isolation Valves to Be Inoperable Was Noted. Caused by Inadequate Design Control.Generated Jco 98-01 ML18016A2641997-12-18018 December 1997 LER 97-024-00:on 971118,SSPS Testing Deficiency Was Noted. Caused by Inadequate Testing Scheme Provided by Ssps Vendor. Revised procedure.W/971218 Ltr ML18016A2501997-11-24024 November 1997 LER 97-023-00:on 920721,RCS PIV Testing Deficiency Was Noted.Caused by Failure to Consider All Testing Variables During Initial Sp Development.Surveillance Tp OST-1506 Was Revised to Incorporate Correction factor.W/971124 Ltr ML18016A2201997-10-22022 October 1997 LER 97-021-01:on 970922,discovered That Spent Fuel Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Misinterpretation of TS Requirements.Revised Daily Surveillance Procedures ML18016A2081997-10-14014 October 1997 LER 97-016-01:on 970608,reactor Trip Occurred,Due to Personnel Error While Attempting to Adjust Power Range Nuclear Instrumentation Channel Following Performance of Calorimetric.Procedures revised.W/971014 Ltr ML18016A2111997-10-14014 October 1997 LER 96-008-02:on 960425,turbine Trip/Reactor Trip Occurred. Caused by High Resistance Connection Resulting from a Phase Switch Jaw & Blade Contacts.Failed a Phase Disconnect Switch on Breaker 52-7 Replaced ML18016A1931997-09-29029 September 1997 LER 97-022-00:on 970829,TS Required Shutdown Due to Expiration of AFW Lco.Caused by Personnel Error.Completed Repairs TDAFW Pump & Returned Plant to Svc on 970831. W/970926 Ltr ML18016A1891997-09-12012 September 1997 LER 97-020-00:on 970814,inadequate Fire Protection Provided for safety-related EDG Fuel Oil Transfer Pump Cables Resulted in Operation Outside Design Basis.Caused by Engineering Oversight.Established Fire watches.W/970912 Ltr ML18016A1881997-09-12012 September 1997 LER 97-021-00:on 970814,spent Fuel Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Misinterpretation of Ts.Directions Provided to Operations.W/970912 Ltr ML18012A8641997-08-18018 August 1997 LER 97-019-00:on 970720,turbine Trip/Reactor Trip Occurred. Caused by Three Phase Fault That Collapsed Excitation Field in Main Generator,Resulting in Generator Lockout.Exciter Rotor Assembly Was replaced.W/970818 Ltr ML18012A8581997-08-0808 August 1997 LER 96-018-01:on 960903,manual Reactor Trip Occurred Due to Loss of Normal Sw.Caused by Mechanical Failure of B Water Pump & a Normal SW to Remain Running Once Manually Started.Restored a Normal SW Pump to Svc ML18012A8551997-08-0808 August 1997 LER 96-013-02:on 961028,condition Outside of Design Basis Where RWST Had Been Aligned w/non-seismically Qualified Sys Was Identified.Caused by Failure to Reconcile Operating Procedure Lineups.Established Administrative Controls ML18012A8471997-07-31031 July 1997 LER 97-018-00:on 970701,determined That Plant Procedures Had Not Received Proper Reviews & Approvals.Caused by Failure to Comply W/Plant Administrative Procedure AP-006.Counseled Involved individuals.W/970731 Ltr ML18012A8371997-07-24024 July 1997 LER 97-S01-00:on 970405,unescorted Access Inappropriately Granted to Contract Outage Workers Was Determined.Caused by Personnel Error.Access Files for Individuals Inappropriately Granted Unescorted Access Were Placed on Access Hold ML18012A8291997-07-11011 July 1997 LER 97-017-00:on 970612,failed to Recognize Inoperable Reactor Afd Monitor.Caused by Personnel Error.Operators Involved in Event Will Be Counseled Prior to Assuming Shift duties.W/970711 Ltr ML18012A8301997-07-0808 July 1997 LER 97-016-00:on 970608,reactor Trip Occurred Due to Personnel Error in Adjusting Power Range (Pr) Nuclear Instrumentation (Ni).Issued Night Order Prohibiting Pr Ni Adjustment When Redundant Channel inoperable.W/970708 Ltr ML18012A8241997-07-0202 July 1997 LER 97-015-00:on 970602,inadequate Auxiliary Feedwater Sys Flow Control Valve Surveillance Testing Deficiency Was Identified.Caused by Failure to Recognize Impact on TS 4.7.1.2.1.Readjusted AFW FCV Actuator spring.W/970702 Ltr ML18022B0181997-06-13013 June 1997 LER 97-014-00:on 970514,SI Occurred During Ssps Surveillance Testing.Caused by Inattention to Detail During Recent Rev to Surveillance Test Procedure Being Used.Revised Deficient Surveillance procedures.W/970613 Ltr ML18012A8081997-06-0909 June 1997 LER 97-013-00:on 970508,entry Into Mode-6 Without Operable Components,Resulting in TS 3.0.4 Violation Occurred.Caused by Personnel Error.Personnel Involved counseled.W/970609 Ltr ML18012A8021997-06-0606 June 1997 LER 97-023-02:on 961114,design Deficiency Was Identified in Emergency DG Protection Circuitry.Caused by Inadequate Plant Design.Revised Surveillance Test Procedures OST-1013 & OST-1073.W/970606 Ltr ML18012A8011997-06-0404 June 1997 LER 97-012-00:on 970505,determined That Previous Auxiliary Control Panel Had Not Verified Operability of Interposing Relays.Caused by Misinterpretation of Tss.Reviewed Other Remote Shutdown Panel Transfer circuitry.W/970604 Ltr ML18012A7951997-05-29029 May 1997 LER 96-023-01:on 961114,design Deficiency in EDG Protection Circuitry Was Identified.Caused by Inadequate Original Plant Design.Surveillance Test Procedures OST-1013 & OST-1073 revised.W/970529 Ltr ML18012A7891997-05-22022 May 1997 LER 97-011-00:on 970422,inappropriate TS Interpretation Resulted in Violations of ECCS Accumulator TS & Entry Into TS 3.0.3.Caused by Procedural Inadequacy.Tsi 88-001 Cancelled 970508 & Procedures revised.W/970522 Ltr ML18012A7871997-05-19019 May 1997 LER 97-010-00:on 970418,design Deficiency Determined Re Reactor Coolant Pump Motor Oil Collection Sys.Caused by RCP Ocs Design Detail.Rcp Ocs Enclosures for Each of Three Installed RCP Motors Have Been modified.W/970519 Ltr ML18012A7761997-05-0707 May 1997 LER 97-009-00:on 970407,fuse Was Removed from CR Ventilation Isolation Signal Power Supply Circuitry Due to Personnel Error.Individuals Involved Were counseled.W/970507 Ltr ML18012A7751997-05-0505 May 1997 LER 97-008-00:on 970404,safety-related AHU Not Declared Inoperable During Maintenance on Associated Temperature Switches Resulting in Violation of Ts.Caused by Incorrect Interpretation.Operations Night Order issued.W/970505 Ltr ML18012A6291997-04-24024 April 1997 LER 97-007-00:on 970325,inoperable CCW Sys TS 3.0.3 Entry Made.Caused by Combination of Procedural Inadequacies, Improper Use of Procedure Guidance & Poor Communication. Applicable Individuals counseled.W/970423 Ltr ML18022B0151997-04-17017 April 1997 LER 97-006-00:on 970318,breach Was Identified in Thermo-Lag Fire Barrier Wall Due to Inadequate Initial Design,Poor Construction Methods & Incomplete as-built Design.Visual Insp of Thermo-Lag Barrier Walls performed.W/970417 Ltr ML18012A6041997-04-0303 April 1997 LER 97-004-00:on 970304,in-plant Spent Fuel Cask Handling Activities Conducted Outside Design Basis.Caused by Lack of Understanding of Requirements.Operations Placed on Hold Pending NRC Review & Approval of procedures.W/970331 Ltr ML18012A6031997-03-31031 March 1997 LER 97-003-00:on 970227,steam Generator Low Level Protection Circuitry Outside Design Basis Occurred.Caused by Inadequate Failure Modes & Effects Analysis Performed as-built Piping Configuration for S/G Level.Review performed.W/970331 Ltr 1999-09-10
[Table view] Category:RO)
MONTHYEARML18017A9181999-10-0808 October 1999 LER 99-008-00:on 991008,CR Emergency Filtration Sys Tech Specs Occurred.Caused by Site Personnel Failed to Recognize That Blocking Open CR Emergency Filtration Sys.Procedures Revised.With 991008 Ltr ML18017A8671999-09-10010 September 1999 LER 99-007-00:on 990811,determined That Cvis ARMs High Alarm Setpoints Were Not within TS Limit.Caused by Not Having Procedure to Verify If Cvis ARM High Alarm Setpoints Were within TS Requirements.Revised Procedures.With 990910 Ltr ML18016B0481999-08-0404 August 1999 LER 99-006-01:on 981124,noted Failure to Comply with TS 4.0.4 & TS 3/4.6.3, Civs. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Was Revised ML18016A9801999-06-0404 June 1999 LER 99-006-00:on 981124,failed to Comply with TS 4.0.4 & TS 3/4.6.3, Civ. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Will Be Revised.With 990604 Ltr ML18016A9111999-04-12012 April 1999 LER 99-005-00:on 990313,plant Exceeded ESFAS TS 3.3.2,Action 21.Caused by Inadequate Procedure Rev Preparation.Licensee Revised Applicable Maint Surveillance Test Procedure (MST-10072) to Identify TS Required Actions.With 990412 Ltr ML18016A8971999-04-0808 April 1999 LER 99-004-00:on 990312,unit Trip Was Noted.Caused by Degraded Condition of SG Water Level Flow Control Valve. Replaced Positioners on All Three FW Regulating Valves.With 990408 Ltr ML18016A8261999-02-22022 February 1999 LER 99-003-00:on 990123,noted That Plant Was Outside Design Basis Due to Isolation of Fire Protection Containment Sprinkler Sys.Caused by Human Error.Restored Containment Sprinkler Sys to Operable Status.With 990222 Ltr ML18016A8111999-02-12012 February 1999 LER 99-002-00:on 990114,RT Due to Not Removing Temporary Device from Relay Following Calibration Was Noted.Caused by Human Error.Counseled Personnel Involved in Event.With 990212 Ltr ML18016A7971999-02-0505 February 1999 LER 99-001-00:on 990106,SF Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Fasteners Bending Under Specific Circumstances.Increased Water Level.With 990205 Ltr ML18016A7941999-01-29029 January 1999 LER 98-004-01:on 980313,identified Design Deficiency Re Potential Runout of Tdafwp.Caused by Inadequate Original AFW Sys Design.Operability Evaluation Was Completed on 980313 & Addl Engineering Analysis Was Performed by Vendor ML18016A7211998-11-17017 November 1998 LER 98-007-00:on 981023,turbine Control Anomaly Caused Manual Rt.Caused by Failure to Incorporate Verbal Vendor Guidance in Operating Procedures.Addl Vendor Guidance Will Be Verified & Added to Procedures.With 981117 Ltr ML18016A4841998-07-0707 July 1998 LER 97-002-01:on 970207,determined That Cold Weather Conditions Resulted in Mfiv Being Potentially Inoperable During Period 970117-20.Caused by Inadequate Design of HVAC Sys.Implemented Mods to Steam Tunnel HVAC Sys ML18016A4701998-06-30030 June 1998 LER 97-021-03:on 980210,discovered That SFP Water Level Had Not Been Verified Greater than 23 Feet Above BWR Fuel Assemblies.Caused by Misinterpretation of TS Requirements. Will Submit TS Change Request to Revise TS 3.9.1.11 ML18016A4491998-06-0808 June 1998 LER 98-006-00:on 980508,failure to Perform Insp & Preventive Maint on MCCB as Required by TS Was Noted.Caused by Inadequate Sps.Tested 9 Pressurizer Heater Bank Breakers by Cycling each.W/980608 Ltr ML18022B0551998-05-20020 May 1998 LER 98-005-00:on 980420,TS Verbatim non-compliance Was Determined.Caused by Misinterpretation of TS Requirements. Issued Memo to Reemphasize Need to Comply W/Literal Meaning of TS Requirements in Verbatim manner.W/980520 Ltr ML18016A4061998-04-30030 April 1998 LER 98-002-01:on 980121,determined Ssps (P-11 Permissive) Testing Deficiency.Caused by Inadequate Review of Initial Ts.Will Revise & Perform Surveillance Test Procedures to Verify Operability of P-11 Permissive ML18016A3841998-04-13013 April 1998 LER 98-004-00:on 980313,design Deficiency Related to Indequate Runout Protection for Turbine Driven AFW Pump Was Identified.Caused by Inadequate Original AFW Sys Design. Evaluation (ESR 98-00100) Will Be completed.W/980409 Ltr ML18016A3441998-03-12012 March 1998 LER 97-021-02:on 980210,identified Failure to Properly Test non-safety Related Pressurizer Porv.Caused by Inadequate Surveillance Test Procedures.Revised Operations Surveillance Test OST-1117 to Include Testing of Subject PORV ML18016A3291998-02-27027 February 1998 LER 98-003-00:on 980129,failure to Perform Shutdown Margin Calculation Required by TS Surveillance Requirements Occurred.Caused by Ambiguity in TS 3.1.3.1.c.Procedures revised.W/980227 Ltr ML18016A3211998-02-20020 February 1998 LER 98-002-00:on 980121,solid State Protection Sys Testing Deficiency Occurred.Caused by Inadequate Review of Initial Tech Specs.Ts Testing Frequency for P-11 Permissive Revised. W/980217 Ltr ML18016A3131998-02-0909 February 1998 LER 98-001-00:on 980109,potential Condition Outside Design Basis Related to Instrument Air Sys Leak Causing SG pre- Heater Bypass Isolation Valves to Be Inoperable Was Noted. Caused by Inadequate Design Control.Generated Jco 98-01 ML18016A2641997-12-18018 December 1997 LER 97-024-00:on 971118,SSPS Testing Deficiency Was Noted. Caused by Inadequate Testing Scheme Provided by Ssps Vendor. Revised procedure.W/971218 Ltr ML18016A2501997-11-24024 November 1997 LER 97-023-00:on 920721,RCS PIV Testing Deficiency Was Noted.Caused by Failure to Consider All Testing Variables During Initial Sp Development.Surveillance Tp OST-1506 Was Revised to Incorporate Correction factor.W/971124 Ltr ML18016A2201997-10-22022 October 1997 LER 97-021-01:on 970922,discovered That Spent Fuel Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Misinterpretation of TS Requirements.Revised Daily Surveillance Procedures ML18016A2081997-10-14014 October 1997 LER 97-016-01:on 970608,reactor Trip Occurred,Due to Personnel Error While Attempting to Adjust Power Range Nuclear Instrumentation Channel Following Performance of Calorimetric.Procedures revised.W/971014 Ltr ML18016A2111997-10-14014 October 1997 LER 96-008-02:on 960425,turbine Trip/Reactor Trip Occurred. Caused by High Resistance Connection Resulting from a Phase Switch Jaw & Blade Contacts.Failed a Phase Disconnect Switch on Breaker 52-7 Replaced ML18016A1931997-09-29029 September 1997 LER 97-022-00:on 970829,TS Required Shutdown Due to Expiration of AFW Lco.Caused by Personnel Error.Completed Repairs TDAFW Pump & Returned Plant to Svc on 970831. W/970926 Ltr ML18016A1891997-09-12012 September 1997 LER 97-020-00:on 970814,inadequate Fire Protection Provided for safety-related EDG Fuel Oil Transfer Pump Cables Resulted in Operation Outside Design Basis.Caused by Engineering Oversight.Established Fire watches.W/970912 Ltr ML18016A1881997-09-12012 September 1997 LER 97-021-00:on 970814,spent Fuel Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Misinterpretation of Ts.Directions Provided to Operations.W/970912 Ltr ML18012A8641997-08-18018 August 1997 LER 97-019-00:on 970720,turbine Trip/Reactor Trip Occurred. Caused by Three Phase Fault That Collapsed Excitation Field in Main Generator,Resulting in Generator Lockout.Exciter Rotor Assembly Was replaced.W/970818 Ltr ML18012A8581997-08-0808 August 1997 LER 96-018-01:on 960903,manual Reactor Trip Occurred Due to Loss of Normal Sw.Caused by Mechanical Failure of B Water Pump & a Normal SW to Remain Running Once Manually Started.Restored a Normal SW Pump to Svc ML18012A8551997-08-0808 August 1997 LER 96-013-02:on 961028,condition Outside of Design Basis Where RWST Had Been Aligned w/non-seismically Qualified Sys Was Identified.Caused by Failure to Reconcile Operating Procedure Lineups.Established Administrative Controls ML18012A8471997-07-31031 July 1997 LER 97-018-00:on 970701,determined That Plant Procedures Had Not Received Proper Reviews & Approvals.Caused by Failure to Comply W/Plant Administrative Procedure AP-006.Counseled Involved individuals.W/970731 Ltr ML18012A8371997-07-24024 July 1997 LER 97-S01-00:on 970405,unescorted Access Inappropriately Granted to Contract Outage Workers Was Determined.Caused by Personnel Error.Access Files for Individuals Inappropriately Granted Unescorted Access Were Placed on Access Hold ML18012A8291997-07-11011 July 1997 LER 97-017-00:on 970612,failed to Recognize Inoperable Reactor Afd Monitor.Caused by Personnel Error.Operators Involved in Event Will Be Counseled Prior to Assuming Shift duties.W/970711 Ltr ML18012A8301997-07-0808 July 1997 LER 97-016-00:on 970608,reactor Trip Occurred Due to Personnel Error in Adjusting Power Range (Pr) Nuclear Instrumentation (Ni).Issued Night Order Prohibiting Pr Ni Adjustment When Redundant Channel inoperable.W/970708 Ltr ML18012A8241997-07-0202 July 1997 LER 97-015-00:on 970602,inadequate Auxiliary Feedwater Sys Flow Control Valve Surveillance Testing Deficiency Was Identified.Caused by Failure to Recognize Impact on TS 4.7.1.2.1.Readjusted AFW FCV Actuator spring.W/970702 Ltr ML18022B0181997-06-13013 June 1997 LER 97-014-00:on 970514,SI Occurred During Ssps Surveillance Testing.Caused by Inattention to Detail During Recent Rev to Surveillance Test Procedure Being Used.Revised Deficient Surveillance procedures.W/970613 Ltr ML18012A8081997-06-0909 June 1997 LER 97-013-00:on 970508,entry Into Mode-6 Without Operable Components,Resulting in TS 3.0.4 Violation Occurred.Caused by Personnel Error.Personnel Involved counseled.W/970609 Ltr ML18012A8021997-06-0606 June 1997 LER 97-023-02:on 961114,design Deficiency Was Identified in Emergency DG Protection Circuitry.Caused by Inadequate Plant Design.Revised Surveillance Test Procedures OST-1013 & OST-1073.W/970606 Ltr ML18012A8011997-06-0404 June 1997 LER 97-012-00:on 970505,determined That Previous Auxiliary Control Panel Had Not Verified Operability of Interposing Relays.Caused by Misinterpretation of Tss.Reviewed Other Remote Shutdown Panel Transfer circuitry.W/970604 Ltr ML18012A7951997-05-29029 May 1997 LER 96-023-01:on 961114,design Deficiency in EDG Protection Circuitry Was Identified.Caused by Inadequate Original Plant Design.Surveillance Test Procedures OST-1013 & OST-1073 revised.W/970529 Ltr ML18012A7891997-05-22022 May 1997 LER 97-011-00:on 970422,inappropriate TS Interpretation Resulted in Violations of ECCS Accumulator TS & Entry Into TS 3.0.3.Caused by Procedural Inadequacy.Tsi 88-001 Cancelled 970508 & Procedures revised.W/970522 Ltr ML18012A7871997-05-19019 May 1997 LER 97-010-00:on 970418,design Deficiency Determined Re Reactor Coolant Pump Motor Oil Collection Sys.Caused by RCP Ocs Design Detail.Rcp Ocs Enclosures for Each of Three Installed RCP Motors Have Been modified.W/970519 Ltr ML18012A7761997-05-0707 May 1997 LER 97-009-00:on 970407,fuse Was Removed from CR Ventilation Isolation Signal Power Supply Circuitry Due to Personnel Error.Individuals Involved Were counseled.W/970507 Ltr ML18012A7751997-05-0505 May 1997 LER 97-008-00:on 970404,safety-related AHU Not Declared Inoperable During Maintenance on Associated Temperature Switches Resulting in Violation of Ts.Caused by Incorrect Interpretation.Operations Night Order issued.W/970505 Ltr ML18012A6291997-04-24024 April 1997 LER 97-007-00:on 970325,inoperable CCW Sys TS 3.0.3 Entry Made.Caused by Combination of Procedural Inadequacies, Improper Use of Procedure Guidance & Poor Communication. Applicable Individuals counseled.W/970423 Ltr ML18022B0151997-04-17017 April 1997 LER 97-006-00:on 970318,breach Was Identified in Thermo-Lag Fire Barrier Wall Due to Inadequate Initial Design,Poor Construction Methods & Incomplete as-built Design.Visual Insp of Thermo-Lag Barrier Walls performed.W/970417 Ltr ML18012A6041997-04-0303 April 1997 LER 97-004-00:on 970304,in-plant Spent Fuel Cask Handling Activities Conducted Outside Design Basis.Caused by Lack of Understanding of Requirements.Operations Placed on Hold Pending NRC Review & Approval of procedures.W/970331 Ltr ML18012A6031997-03-31031 March 1997 LER 97-003-00:on 970227,steam Generator Low Level Protection Circuitry Outside Design Basis Occurred.Caused by Inadequate Failure Modes & Effects Analysis Performed as-built Piping Configuration for S/G Level.Review performed.W/970331 Ltr 1999-09-10
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML18017A9181999-10-0808 October 1999 LER 99-008-00:on 991008,CR Emergency Filtration Sys Tech Specs Occurred.Caused by Site Personnel Failed to Recognize That Blocking Open CR Emergency Filtration Sys.Procedures Revised.With 991008 Ltr ML18017A9151999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Shearon Harris Npp. with 991012 Ltr ML20217A9931999-09-30030 September 1999 NRC Regulatory Assessment & Oversight Pilot Program, Performance Indicator Data ML18017A8671999-09-10010 September 1999 LER 99-007-00:on 990811,determined That Cvis ARMs High Alarm Setpoints Were Not within TS Limit.Caused by Not Having Procedure to Verify If Cvis ARM High Alarm Setpoints Were within TS Requirements.Revised Procedures.With 990910 Ltr ML18017A8621999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Harris Nuclear Plant.With 990908 Ltr ML18016B0481999-08-0404 August 1999 LER 99-006-01:on 981124,noted Failure to Comply with TS 4.0.4 & TS 3/4.6.3, Civs. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Was Revised ML18017A8361999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Shearon Harris Nuclear Power Plant.With 990811 Ltr ML18016B0151999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Shearon Harris Npp. with 990713 Ltr ML20196H8621999-06-30030 June 1999 NRC Regulatory Assessment & Oversight Pilot Program, Performance Indicator Data, June 1999 Rept ML18016A9801999-06-0404 June 1999 LER 99-006-00:on 981124,failed to Comply with TS 4.0.4 & TS 3/4.6.3, Civ. Caused by post-maint Testing That Did Not Adequately Test Control Circuitry & Verify Isolation Time Following Maint.Procedure Will Be Revised.With 990604 Ltr ML18016A9851999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Shearon Harris Nuclear Plant,Unit 1.With 990614 Ltr ML18017A8981999-05-12012 May 1999 Technical Rept Entitled, Harris Nuclear Plant-Bacteria Detection in Water from C&D Spent Fuel Pool Cooling Lines. ML18016A9581999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Shearon Harris Nuclear Plant,Unit 1.With 990513 Ltr ML18016A9011999-04-12012 April 1999 Part 21 Rept Re Defect in Component of DSRV-16-4,Enterprise DG Sys.Caused by Potential Problem with Connecting Rod Assemblies Built Since 1986,that Have Been Converted to Use Prestressed Fasteners.Affected Rods Should Be Inspected ML18016A9111999-04-12012 April 1999 LER 99-005-00:on 990313,plant Exceeded ESFAS TS 3.3.2,Action 21.Caused by Inadequate Procedure Rev Preparation.Licensee Revised Applicable Maint Surveillance Test Procedure (MST-10072) to Identify TS Required Actions.With 990412 Ltr ML18016A8971999-04-0808 April 1999 LER 99-004-00:on 990312,unit Trip Was Noted.Caused by Degraded Condition of SG Water Level Flow Control Valve. Replaced Positioners on All Three FW Regulating Valves.With 990408 Ltr ML18016A8941999-04-0505 April 1999 Revised Pages 20-25 to App 4A of non-proprietary Version of Rev 3 to HI-971760 ML18016A9101999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Shearon Harris Nuclear Power Plant.With 990413 Ltr ML18016A8661999-03-31031 March 1999 Shnpp Operator Training Simulator,Simulator Certification Quadrennial Rept. ML18017A8931999-02-28028 February 1999 Risks & Alternative Options Associated with Spent Fuel Storage at Shearon Harris Nuclear Power Plant. ML18016A8551999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for Shearon Harris Npp. with 990312 Ltr ML18016A8261999-02-22022 February 1999 LER 99-003-00:on 990123,noted That Plant Was Outside Design Basis Due to Isolation of Fire Protection Containment Sprinkler Sys.Caused by Human Error.Restored Containment Sprinkler Sys to Operable Status.With 990222 Ltr ML18016A8531999-02-18018 February 1999 Non-proprietary Rev 3 to HI-971760, Licensing Rept for Expanding Storage Capacity in Harris SFP 'C' & 'D'. ML18016A8111999-02-12012 February 1999 LER 99-002-00:on 990114,RT Due to Not Removing Temporary Device from Relay Following Calibration Was Noted.Caused by Human Error.Counseled Personnel Involved in Event.With 990212 Ltr ML18016A7971999-02-0505 February 1999 LER 99-001-00:on 990106,SF Pool Water Level Was Not Maintained Greater than 23 Feet Above Stored BWR Fuel Assemblies.Caused by Fasteners Bending Under Specific Circumstances.Increased Water Level.With 990205 Ltr ML18022B0631999-02-0404 February 1999 Rev 0 to Nuclear NDE Manual. with 28 Oversize Uncodable Drawings of Alternative Plan Scope & 4 Oversize Codable Drawings ML20202J1161999-02-0101 February 1999 SER Accepting Relief Requests Associated with Second 10-year Interval Inservice Testing Program ML18016A8041999-01-31031 January 1999 Monthly Operating Rept for Jan 1999 for Shearon Harris Nuclear Power Plant.With 990211 Ltr ML18016A7941999-01-29029 January 1999 LER 98-004-01:on 980313,identified Design Deficiency Re Potential Runout of Tdafwp.Caused by Inadequate Original AFW Sys Design.Operability Evaluation Was Completed on 980313 & Addl Engineering Analysis Was Performed by Vendor ML18016A7801998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for Shearon Harris Npp. with 990113 Ltr ML18016A7671998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for Shnpp,Unit 1.With 981215 Ltr ML18016A9731998-11-28028 November 1998 Changes,Tests & Experiments, for Harris Nuclear Plant.Rept Provides Brief Description of Changes to Facility & Summary & of SE for Each Item That Was Implemented Under 10CFR50.59 Between 970608-981128.With 990527 Ltr ML18016A8351998-11-28028 November 1998 ISI Summary 8th Refueling Outage for Shearon Harris Power Plant,Unit 1. ML18016A7411998-11-25025 November 1998 Rev 1 to Shnpp Cycle 9 Colr. ML18016A7211998-11-17017 November 1998 LER 98-007-00:on 981023,turbine Control Anomaly Caused Manual Rt.Caused by Failure to Incorporate Verbal Vendor Guidance in Operating Procedures.Addl Vendor Guidance Will Be Verified & Added to Procedures.With 981117 Ltr ML18016A7071998-11-0303 November 1998 Rev 0 to Harris Unit 1 Cycle 9 Colr. ML18016A7201998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for Shearon Harris Nuclear Power Plant.With 981113 Ltr ML20154F8701998-10-0606 October 1998 Safety Evaluation Authorizing Proposed Alternative to Requirements of OMa-1988,Part 10,Section 4.2.2.3 for 21 Category a Reactor Coolant Sys Pressure Isolation Valves ML18016A6201998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for Harris Nuclear Power Plant.With 981012 Ltr ML18016A5971998-09-21021 September 1998 Rev 1 to Harris Unit 1 Cycle 8 Colr. ML18016A5881998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for Shnpp,Unit 1.With 980914 Ltr ML18016A5071998-07-31031 July 1998 Monthly Operating Rept for Jul 1998 for Shearon Harris Nuclear Plant.W/980811 Ltr ML18016A9431998-07-0707 July 1998 Rev 1 to QAP Manual. ML18016A4841998-07-0707 July 1998 LER 97-002-01:on 970207,determined That Cold Weather Conditions Resulted in Mfiv Being Potentially Inoperable During Period 970117-20.Caused by Inadequate Design of HVAC Sys.Implemented Mods to Steam Tunnel HVAC Sys ML18016A9371998-06-30030 June 1998 Technical Rept on Matl Identification of Spent Fuel Piping Welds at Hnp. ML18016A4861998-06-30030 June 1998 Monthly Operating Rept for June 1998 for SHNPP.W/980715 Ltr ML18016A4701998-06-30030 June 1998 LER 97-021-03:on 980210,discovered That SFP Water Level Had Not Been Verified Greater than 23 Feet Above BWR Fuel Assemblies.Caused by Misinterpretation of TS Requirements. Will Submit TS Change Request to Revise TS 3.9.1.11 ML18016A4491998-06-0808 June 1998 LER 98-006-00:on 980508,failure to Perform Insp & Preventive Maint on MCCB as Required by TS Was Noted.Caused by Inadequate Sps.Tested 9 Pressurizer Heater Bank Breakers by Cycling each.W/980608 Ltr ML18016A4521998-05-31031 May 1998 Monthly Operating Rept for May 1998 for Shearon Harris Nuclear Power Plant.W/980612 Ltr ML18016A7711998-05-26026 May 1998 Non-proprietary Rev 2 to HI-971760, Licensing Rept for Expanding Storage Capacity in Harris Spent Fuel Pools 'C' & 'D'. 1999-09-30
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CATEGORY 1 REGULATORY INFORMATION DISTRIBUTION SYSTEM
~ (RIDS)
ACCESSION NBR:9609030388 DOC.DATE: 96/08/26 NOTARIZED: NO DOCKET FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina 05000400
-AUTH. NAME AUTHOR AFFILIATION VERRILLZ,M. Carolina Power 6 Light Co.
DONAHUE,J.W. Carolina Power '& Light Co.
RECZP.NAME RECIPIENT AFFILIATION
SUBJECT:
LER 96-012-00:on 960724,SIII inverter was taken OOS for repair.W/plant in mode 1 at 100% power. Caused by faulty fer.ro-resonant transformer within inverter's.Repairs a load testing for SIZZ inverter were completed.W/960826 ltr.
DISTRIBUTION CODE: ZE22T COPIES RECEIVED:LTR ENCL SIZE:
TITLE: 50.73/50.9 'Licensee Event Report (LER), Incident Rpt, etc.
NOTES:Application for permit renewal filed. 05000400 G 0
RECIPIENT COPIES RECIPIENT COPIES ZD CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-1 PD 1 1 LE,N 1 1 INTERNAL: ACRS 1 1 AEOD S AB 2 2 AEOD/SPD/RRAB 1 1 1 1 NRR/DE/ECGB 1 1 1 1 NRR/DE/EMEB 1 1 NRR/DRCH/HHFB 1 1 NRR/DRCH/HICB 1 1 NRR/DRCH/HOLB 1 1 NRR/DRCH/HQMB 1 1 NRR/DRPM/PECB 1 1 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 D RES/DSIR/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCE,J H 2 2 NOAC MURPHY,G.A 1 1 NOAC POORE,W. 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 N
NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5D-5(EXT. 415-2083) TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 26 ENCL 26
Carolina Power 8 Light Company Harris Nuclear Plant PO 8ox )65 New Hill NC 27562 AUG 2 6 1996 U.S. Nuclear Regulatory Commission Serial: HNP-96-142 ATTN: NRC Document Control Desk 10CFR50.73 Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 96-012-00 Sir or Madam:
In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report describes a Technical Specification 3.0.3 entry that occurred on July 25, 1996.
Sincerely, J. W. Donahue Director of Site Operations Harris Plant MV Enclosure c: Mr. J. B. Brady (HNP Senior NRC Resident)
Mr. S. D. Ebneter (NRC Regional Administrator, RegionII)
Mr. N. B. Le (NRC Project Manager- NRR) 9609030388 960826 PDR ADOCK 05000400 S PDR State Road H34 New Hill NC
II I NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 (4 95) EXPIRES 04/30/96 ESt(MATEO BURDEN PER RESPONSE'O COMPLY WITH THIS MANDATORY UIFORMATIDN COllECTION REDDEST: 500 HRS, REPORTED LESSONS lEARNEO ARE LXCENSEE EVENT REPORT (LER) U(CORPDRATEO INTO THE UCENSING PROCESS ANO FEO BACK TO U(OUSTRT.
fORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE (NFORMATION ANO RECORDS MANAGEMENt BRANCH IT.6 F33L US. NUClEAR REGUUITORT COMMISSION.
(See reverse for required number of WASHU(GTON, OC 20555000). AND TO THE PAPERWORK REDUCTION PROJECT (3150.
digits/characters for each block) 0104L Off(CE OF MANAGEMEN'r AND BUDGET, WASHINGTON, OC 205(KL FACILITY NAME (I) DOCKET NUMBER (2) PAGE (3)
Harris Nuclear Plant Unit-1 50-400 1 OF 2 TITLE (4)
Technical Specification entry when transferring the SIII Instrument Bus back to the'inverter with RWST level transmitter LT-993 out of service.
EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (6)
FACIUTY NAME DOCKET NUMBER SEOUENTIAL REVISION MONTH OAY YEAR MONTH OAY YEAR NULlBER NUMBER 05000 FACILITYNAME DOCKET NUMBER 25 96 96 012 0 8 26 96 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR BI (Check one or moro) (11) iMiODE (9) 20.2201(b) 20.2203(a)(2)(v) )( 50.73(a)(2)(i) 50.73(a)(2)(viii)
POWER 20.2203(a) (1) 20.2203(a)(3)(i) 50. 73(a) (2) (ii) 50.73(a)(2)(x)
LEVEL (10) 100% 20.2203(a)(3) (ii) 50.73(a)(2)(iii) 73.71 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(4) 50.73(a)(2)(iv) OTHER 20.2203(a) (2) (iii) 50.36(c)(1) 50.73(a)(2)(v) Specify in Abstract below or in NRC Form 366A 20.2203(a)(2)(iv) 50.36(c) (2) 50.73(a) (2) (vii)
LICENSEE CONTACT FOR THIS LER (12)
TELEPHONE NUMBER (Incrude Area Code)
Michael Verrl)(i Sr. Analyst - Licensing (919) 362-2303 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
REPORTABLE REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER CAUSE SYSTEM COMPONENT MANUFACTURER TO NPROS TO NPROS ED INVT W121 JE LT ,8080 Y SUPPLEMENTAL REPORT EXPECTED (14) EXPECTED MONTH OAY YEAR YES SUBMISSION (If yes, complete EXPECTED SUBMISSION DATE). X NO DATE (15)
ABSTRACT (Limit to 1400 spaces, i.a., approximately 15 single.spaced typewritten lines) (16)
At approximately 2158 hours0.025 days <br />0.599 hours <br />0.00357 weeks <br />8.21119e-4 months <br /> on July 24, 1996, with the plant in i>lode at 100% power, the SIII Inverter was taken out of 1
service for repair and at approximately 2219, the SIII instrument bus was aligned to the alternate power supply. Technical Specifications require the instrument bus to be re-energized from its associated inverter connected to its associated DC power supply within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or commence plant shutdown. At approximately 0009 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> on July 25, 1996, Refueling Water Storage Tank (RWST) Level Transmitter LT-993 was declared inoperable due to spiking observed by control room personnel. Estimated time to restore LT-993 exceeded the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> requirement to reconnect the SIII instrument bus to the SIII Inverter. Due to these conditions, Technical Specification 3.0.3 was entered at approximately 1623 hours0.0188 days <br />0.451 hours <br />0.00268 weeks <br />6.175515e-4 months <br /> when the SIII instrument bus was de-energized for 12 minutes to transfer it back to its normal source (SIII Inverter), coincident with LT-993 being inoperable. Entry into Technical Specification 3.0.3 was required since RWST Level Transmitter LT-993 is a channel IV instrument and, during the 12 minute transfer period, channel III RWST level transmitter LT-992 was disabled by de-energizing the SIII instrument bus, thereby removing two of the four RWST level transmitters from service.
Technical Specification 3.0.3 was exited at approximately 1635 upon completion of the instrument bus power supply transfer process.
The above scenario and the need to enter Technical Specification 3.0.3 was identified, discussed in advance and evaluated by plant management and the Plant Nuclear Safety Comminee. The decision to allow a one-time, short duration Technical Specification 3.0.3 entry to transfer the SIII instrument bus to its normal power source was based on the following: (1) technical specifications allow two out of four RWST level transmitters to be bypassed for up to two hours for surveillance testing, thereby bounding the condition, and (2) transferring the SIII instrument bus back to the SIII Invcrter places the 120 Volt Engineered Safety Feature Uninteruptable AC System in its preferred, design configuration which provides the most reliable instrument bus power supply source, and (3) this evolution did not present an adverse impact to plant safety.
N )
NRC FORM 366A U.S. NUC(EAR REOU(ATORT COMMISSION (4 BQ LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACI(ITT NAME (ll OOCNET lER NUMBER (6) PACE (3)
SEOUENTIAL R(V SION TEAR NUMBER NUMBER Shearon Harris Nuclear Plant ~ Unit N1 50400 2 OF 2 96 - 012 - 00 TEXT Pr msuu spusu is suuui ssr usu uditrmml supms ul At))C Fmm 36QS (I 7)
EVENT DESCRIPTION:
At approximately 2158 hours0.025 days <br />0.599 hours <br />0.00357 weeks <br />8.21119e-4 months <br /> on July 24, 1996, with the plant in Mode 1 at 100% power, the 7.5 KVA SIII Instrument Inverter (EIIS Code: ED-INVT) was taken out of service to allow for repairs and at approximately 2219, the SIII instrument bus (1DP-1A-SIII) was aligned to the alternate AC power supply (120 Volt Power Panel 1A311-SA). The SIII Inverter had recently experienced an approximate 50% degraded output voltage condition which was caused by a faulty ferro-resonant transformer. Post maintenance load testing of the SIII Inverter, following replacement of the bad transformer, was completed at approximately 1225 hours0.0142 days <br />0.34 hours <br />0.00203 weeks <br />4.661125e-4 months <br /> on July 25, 1996. Harris Nuclear Plant Technical Specification 3.8.3.1 (Electrical Power Systems - Onsite Power Distribution) Action c requires the instrument bus to be re-energized from its associated inverter connected to its associated DC power supply within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or commence plant shutdown.
At approximately 0009 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> on July 25, 1996, Refueling Water Storage Tank (RWST) level transmitter LT-993 (EIIS Code: JE-LT) was observed to be declared inoperable due to spiking observed by control room personnel. To return LT-993 to service, the transmitter and power supply card would need to be replaced and time estimates to complete these actions indicated that the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> requirement to reconnect the SIII instrument bus to the SIII Inverter would be exceeded.
Due to these conditions, Technical Specification 3.0.3 was entered at approximately 1623 hours0.0188 days <br />0.451 hours <br />0.00268 weeks <br />6.175515e-4 months <br /> when the SIII instrument bus was de-energized for 12 minutes to transfer it back to its normal source (SIII Inverter), coincident with LT-993 being inoperable.'ntry into Technical Specification 3.0.3 was required since RWST level transmitter LT-993 is a channel IV instrument and during the 12 minute transfer period, channel III RWST level transmitter LT-992 was disabled by de-energizing the SIII instrument bus, thereby removing two of the four RWST level transmitters from service. Technical Specification 3.0.3 was exited at approximately 1635 upon completion of the instrument bus power supply transfer process.
The above scenario and the need to enter Technical Specification 3.0.3 was identified, discussed in advance and evaluated by plant management and the Plant Nuclear Safety Committee. The decision to allow a one-time, short duration Technical Specification 3.0.3 entry to transfer the SIII instrument bus to its normal power source was based on the following: (1) technical specifications allow two out of four RWST level transmitters to be bypassed for up to two hours for surveillance testing, thereby bounding the condition, and (2) transferring the SIII instrument bus back to the SIII Inverter places the 120 Volt Engineered Safety Feature (ESF) Uninteruptable AC System in its preferred, design configuration which provides the most reliable instrument bus power supply source, and (3) this evolution did not present an adverse impact to plant safety.
CAUSE:
The failure of the SIII Inverter was attributed to a faulty ferro-resonant transformer within the inverter's internal circuitry.
The cause of the RWST Level Transmitter, LT-993 was caused by either a bad power supply circuit board card or a malfunction within the level transmitter itself. The Technical Specification 3.0.3 entry was reviewed and approved in advance by plant management and the Plant Nuclear Safety Committee.
SAFETY SIGNIFICANCE:
There were no safety consequences as a result of this event. The short duration Technical Specification 3.0.3 entry to transfer the SIII instrument bus back to the SIII Inverter presented no adverse impact to plant safety based on the fact that technical specifications allow two out of four RWST level transmitters to be bypassed for up to two hours for surveillance testing, thereby bounding the condition. Transferring the SIII instrument bus back to the SIII Inverter places the 120 Volt ESF Uninteruptable AC System in its preferred, design configuration which provides the most reliable source of power to the instrument bus. This event is being reported per 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by technical specifications.
PREVIOUS SIMILAR EVENTS:
There have been no other Technical Specification 3.0.3 entries to re-align the 120 Volt ESF Uninterruptable AC System.
CORRECTIVE ACTIONS COMPLETED:
- 1. Repairs and load testing for the SIII Inverter were completed at approximately 1225 hours0.0142 days <br />0.34 hours <br />0.00203 weeks <br />4.661125e-4 months <br /> on July 25, 1996.
- 2. Replacement of the LT-993 RWST level transmitter and power supply card and subsequent post-maintenance acceptance testing were completed at approximately 2050 hours0.0237 days <br />0.569 hours <br />0.00339 weeks <br />7.80025e-4 months <br /> on July 26, 1996.
RM 3 A (4-95)
4%