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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20012C5131990-03-16016 March 1990 LER 86-029-02:on 860718,19,21 & 870508,loss of Reactor Protection Sys Power Occurred Due to Spurious Tripping of Alternate Feed EPA Breakers.Caused by Low Output Voltage of Alternate Feed Transformer.Output adjusted.W/900316 Ltr ML20006E1571990-02-0909 February 1990 LER 90-001-00:on 900117,unplanned Actuation of ESF Reactor Bldg Standby Ventilation Sys B Occurred,Causing Interlocking Relays in Control Circuits to Deenergize.Caused by Transient Voltage Dip.Procedures Re Bus Loads modified.W/900209 Ltr ML19354D8331990-01-12012 January 1990 LER 89-011-00:on 891222,unplanned Actuation of ESF Primary Containment Isolation Sys Occurred When Performing Sys Layup Implementation Package for Hpci.Caused by Inadequate Procedure.Breaker Positions changed.W/900112 Ltr ML20005F8641990-01-11011 January 1990 LER 89-010-00:on 891212,unplanned Actuation of ESF Control Room Air Conditioning Train a Occurred.Caused by Removal of Leads from Relay During Test to Prevent ESF Sys Actuations. Electrical Relay Replaced & Wiring Mod made.W/900111 Ltr ML20011D2371989-12-15015 December 1989 LER 89-009-00:on 891115,notification Received of Potential Failure Mechanism of Four 3-way Solenoid Operated Pilot Valves.Caused by Incorrect Mounting of Valves.Valves Remounted Vertically & Field Walkdown done.W/891215 Ltr ML19332C5591989-11-15015 November 1989 LER 89-008-00:on 891016,control Room Alarms Received Indicating Fire Pump Had Started & Deluge Valve Had Opened. Caused by Actuation of Manual Pull Station.Deluge Sys Restored to Normal & Personnel interviewed.W/891115 Ltr 1993-06-11
[Table view] Category:RO)
MONTHYEARML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20012C5131990-03-16016 March 1990 LER 86-029-02:on 860718,19,21 & 870508,loss of Reactor Protection Sys Power Occurred Due to Spurious Tripping of Alternate Feed EPA Breakers.Caused by Low Output Voltage of Alternate Feed Transformer.Output adjusted.W/900316 Ltr ML20006E1571990-02-0909 February 1990 LER 90-001-00:on 900117,unplanned Actuation of ESF Reactor Bldg Standby Ventilation Sys B Occurred,Causing Interlocking Relays in Control Circuits to Deenergize.Caused by Transient Voltage Dip.Procedures Re Bus Loads modified.W/900209 Ltr ML19354D8331990-01-12012 January 1990 LER 89-011-00:on 891222,unplanned Actuation of ESF Primary Containment Isolation Sys Occurred When Performing Sys Layup Implementation Package for Hpci.Caused by Inadequate Procedure.Breaker Positions changed.W/900112 Ltr ML20005F8641990-01-11011 January 1990 LER 89-010-00:on 891212,unplanned Actuation of ESF Control Room Air Conditioning Train a Occurred.Caused by Removal of Leads from Relay During Test to Prevent ESF Sys Actuations. Electrical Relay Replaced & Wiring Mod made.W/900111 Ltr ML20011D2371989-12-15015 December 1989 LER 89-009-00:on 891115,notification Received of Potential Failure Mechanism of Four 3-way Solenoid Operated Pilot Valves.Caused by Incorrect Mounting of Valves.Valves Remounted Vertically & Field Walkdown done.W/891215 Ltr ML19332C5591989-11-15015 November 1989 LER 89-008-00:on 891016,control Room Alarms Received Indicating Fire Pump Had Started & Deluge Valve Had Opened. Caused by Actuation of Manual Pull Station.Deluge Sys Restored to Normal & Personnel interviewed.W/891115 Ltr 1993-06-11
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20140G4481997-05-0101 May 1997 Part 21 Rept Re Potential Defect in Component of Dsrv & Dsr Enterprise Standby Diesel Generator Sys.Recommends That Springs Be Inspected on Periodic Basis,Such as During Refueling Outages ML20135D8011996-11-26026 November 1996 Part 21 Rept Re Two Safety Related Valves Supplied by Velan Valve Corp Were Not in Compliance W/Originally Supplied QA Documentation.Returned Valves to Velan in May 1996 & on 961120 Velan Advised That Valves Had Been Misplaced ML20080G4691995-01-26026 January 1995 Record of Telcon W/Nrc & Licensees 950126 to Clarify Position Re Dispositioning of Exempt Sources Listed in Section 6.3.3 of Shoreham Termination Survey Final Rept Dtd Oct 1994 ML20069F0001994-01-24024 January 1994 Vols 1-4 to Shoreham Decommissioning Project Termination Survey Final Rept ML20058K3841993-12-0909 December 1993 Part 21 Rept Re Potential Defect in Component of Dsrv & Dsr Enterprise Standby DG Sys,Regarding Potential Problem W/ Subcover Assembled Atop Power Head ML20057F2261993-09-30030 September 1993 Safety Evaluation Supporting Exemption Request from Requirements of 10CFR50.54(q) for License NPF-82 ML20056C7181993-07-14014 July 1993 SE Supporting Amend 10 to License NPF-82 ML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20045C8881993-06-0808 June 1993 Vols 1 & 2 to Refueling Jib Crane 1T31-CRN-008A Incident Root Cause Analysis. W/One Oversize Encl ML20044C1181993-02-28028 February 1993 Shoreham Nuclear Power Station Updated Decommissioning Plan. ML20128P6451993-02-28028 February 1993 Snps Decommissioning Project Termination Survey Final Rept for Steam Turbine Sys (N31) ML20128P7431993-02-19019 February 1993 Rev 3 to 93X027, Nuclear QA Surveillance Rept ML20127H2301993-01-15015 January 1993 Part 21 Rept Re Potential Defeat in Component of Dsrv & Dsr Enterprise Standby DG Sys.Starting Air Distributor Housing Assemblies Installed as Replacement Parts at Listed Sites ML20126B0421992-12-17017 December 1992 Final Part 21 Rept Re Potential Problem W/Steel Cylinder Heads.Initially Reported on 921125.Caused by Inadequate Cast Wall Thickness at 3/4-inch-10 Bolt Hole.Stud at Location Indicated on Encl Sketch Should Be Removed ML20125C7161992-12-0707 December 1992 Part 21 Rept Re Possibility for Malfunction of Declutching Mechanisms in SMB/SB-000 & SMB/SB/SBD-00 Actuators. Malfunction Only Occurs During Seismic Event.Balanced Levers May Be Purchased from Vendor.List of Affected Utils Encl ML20127P5861992-11-23023 November 1992 Followup to 921005 Part 21 Rept Re Potential Defect in SB/SBD-1 Housing Cover Screws.Procedure Re Replacement of SBD-1 Spring Cover Bolts Encl.All Fasteners Should Be Loosened & Removed.List of Affected Utils Encl ML20128B9641992-10-31031 October 1992 Rev 0 to Shoreham Decommissioning Project Termination Survey Plan ML20118B4391992-09-11011 September 1992 Part 21 Rept Re Degradation in Abb Type 27N Undervoltage Relays Used in Electrical Switchgear.Recommends That Users Review Applications Requiring Exposures Greater than 1E03 Rads TID W/Time Delay Function Option ML20099H5781992-07-31031 July 1992 Rev 4 to Shoreham Defueled Sar ML20114A6311992-07-28028 July 1992 Shoreham Decommissioning Plan ML20101K5791992-06-25025 June 1992 Long Island Power Authority Shoreham Decommissioning Project,Shoreham Nuclear Power Station,Technical Rept on Water Processing & Water Mgt Activities for Reactor Pressure Vessel & Wet Cutting Station ML20094L1271992-03-13013 March 1992 Amend 1 to Part 21 Rept 159 Re Potential Defect in Power Cylinder Liner.Initially Reported on 920115.Caused by Liner/ Block Fit & Localized Matl Microstructure.All Drawings & Specs Revised to Address Matl Design Requirements ML20082M5081991-08-26026 August 1991 Rev 3 to Shoreham Defueled Sar PM-91-125, Monthly Operating Rept for Jul 1991 for Shoreham Nuclear Power Station1991-07-31031 July 1991 Monthly Operating Rept for Jul 1991 for Shoreham Nuclear Power Station PM-91-112, Monthly Operating Rept for Jun 1991 for Shoreham Nuclear Power Station1991-06-30030 June 1991 Monthly Operating Rept for Jun 1991 for Shoreham Nuclear Power Station PM-91-075, Monthly Operating Rept for Apr 1991 for Shoreham Nuclear Power Station1991-04-30030 April 1991 Monthly Operating Rept for Apr 1991 for Shoreham Nuclear Power Station ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr SNRC-1806, Revised Pages 2 & 6 to Encl a of 10CFR50.59 Annual Rept for 19901991-04-15015 April 1991 Revised Pages 2 & 6 to Encl a of 10CFR50.59 Annual Rept for 1990 PM-91-058, Monthly Operating Rept for Mar 1991 for Shoreham Nuclear Power Station1991-03-31031 March 1991 Monthly Operating Rept for Mar 1991 for Shoreham Nuclear Power Station PM-91-037, Monthly Operating Rept for Feb 1991 for Shoreham Nuclear Power Station1991-02-28028 February 1991 Monthly Operating Rept for Feb 1991 for Shoreham Nuclear Power Station PM-91-016, Monthly Operating Rept for Jan 1991 for Shoreham Nuclear Power Station1991-01-31031 January 1991 Monthly Operating Rept for Jan 1991 for Shoreham Nuclear Power Station SNRC-1797, 10CFR 50.59 Annual Rept of Facility Changes,Procedure Changes,Tests & Experiments for Jan-Dec 19901990-12-31031 December 1990 10CFR 50.59 Annual Rept of Facility Changes,Procedure Changes,Tests & Experiments for Jan-Dec 1990 SNRC-1794, Shoreham Nuclear Power Station Annual Operating Rept,19901990-12-31031 December 1990 Shoreham Nuclear Power Station Annual Operating Rept,1990 SNRC-1799, Lilco 1990 Annual Rept1990-12-31031 December 1990 Lilco 1990 Annual Rept ML20069Q3901990-12-31031 December 1990 Shoreham Nuclear Power Station Decommissioning Plan. (Filed in Category P) ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20056A2001990-07-31031 July 1990 Safety Evaluation Supporting Amend 6 to License NPF-82 PM-90-097, Monthly Operating Rept for June 1990 for Shoreham Nuclear Power Station1990-06-30030 June 1990 Monthly Operating Rept for June 1990 for Shoreham Nuclear Power Station ML20055E3911990-06-25025 June 1990 Safety Evaluation Supporting Amend 5 to License NPF-82 PM-90-083, Monthly Operating Rept for May 1990 for Shoreham Nuclear Power Station1990-05-31031 May 1990 Monthly Operating Rept for May 1990 for Shoreham Nuclear Power Station 05000322/LER-1988-0151990-05-16016 May 1990 LER 88-015-02:on 880916,seismic Monitoring Instrumentation, Including Peak Acceleration Recorders,Removed from Svc for More than 30 Days Due to Corrosion on Scratch Plates.Cover Gasket Replaced & Thermal Barrier Mount to Be Installed 05000322/LER-1986-0391990-05-16016 May 1990 LER 86-039-01:on 861006,unplanned Initiation of Reactor Bldg Standby Ventilation Sys Occurred W/All Rods Inserted in Core.Caused by Faulty Design of Retaining Device.Warning Signs Attached to Valve Actuator & Valve Mod Initiated 05000322/LER-1986-0321990-05-16016 May 1990 LER 86-032-01:on 860728,RWCU Isolated on High Differential Flow Sensed by Steam Leak Detection Sys While Placing Filter Demineralizers in Operation.Cause Not Determined. Operating Procedures Revised to Monitor RWCU Sys 05000322/LER-1987-0091990-05-16016 May 1990 LER 87-009-01:on 870203,full Reactor Trip Occurred Due to Perturbation in Ref Leg.Caused by Spurious Low Level Reactor Pressure Vessel Water Level Signal.Existing Level & Pressure Transmitters Replaced W/Newer Models 05000322/LER-1987-0221990-05-16016 May 1990 LER 87-022-01:on 870604,HPCI Test Valve to Condensate Storage Tank,Globe Valve & Hpci/Rcic Test Valve to Condensate Storage Tank Failed to Close Against Sys Operating Pressure.Disc of motor-operated Valve 37 Modified 05000322/LER-1989-0051990-05-16016 May 1990 LER 89-005-01:on 890321,results of Local Leak Rate Test of Core Spray Suction Valve a Determined That Leakage,When Combined W/All Type B & C Penetration Leakages,Exceeded Tech Spec Limit.Caused by Normal Valve Degradation 05000322/LER-1989-0031990-05-16016 May 1990 LER 89-003-01:on 890310,emergency Diesel Generator (EDG) 102 Manually Shutdown During 18-month Surveillance Test Due to Failure of EDG Output Breaker.Cause Not Determined. Replacement Breaker Installed in Cubicle 102-8 05000322/LER-1985-0591990-05-16016 May 1990 LER 85-059-01:on 851219,half Reactor Trip,Full NSSS Shutoff Sys Isolation & Reactor Bldg Standby Ventilation Sys Initiation Occurred Due to Loss of Power to Reactor Protection Sys Bus B.Assembly Breaker Reset 05000322/LER-1987-0351990-05-16016 May 1990 LER 87-035-02:on 871221,880106 & 0330,high Energy Line Break Logic Isolations of RWCU & Main Steam Line Drain Valves Occurred.Caused by Problems W/Temp Monitoring Units. Grounding Scheme Changed & Transformers Rewired 05000322/LER-1988-0031990-05-16016 May 1990 LER 88-003-01:on 880322,unplanned Automatic Initiation of Reactor Bldg Standby Ventilation Sys Side a Occurred During Deenergization of Relay.Caused by Close Placement of Relay Terminals.Wiring Inside Electrical Panels Reworked 1997-05-01
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On three separate occasions, High Energy Line Break Logic Isolations l
of the Reactor Water Cleanup (RWCU) and Main Steam Line (MSL) Drain Valves (iG33*MOV-034 and 1B21*MOV-032) occurred most likely due to l high amplitude electrical noise on the Isolated Ground System (IGS). !
At the time of the events, the plant was in Operational Condition 4 l (Cold Shutdown) with theThe mode switch in Shutdown and all rods first two events occurred on December 21, inserted in the core.
1987 and January 6, 1988. An investigation discovered a grounding >
problem within the Primary Containment Monitoring Panel (PCM) where the Temperature Monitoring Units (TMU) are located. This particular l
problem was alleviated as a result of an engineering change which grounded the power supplies for the TMUs to the IGS. However, a third isolation occurred on March 30, 1988 due to a similar problem with the IGS. In all three events, operators verified the signals as false and returned the systems to their normal configurations. l Plant Management was notified of the events and the NRC was notified in accordance with 10CFR50.72. This Supplemental Report is being submitted to list the status of corrective actions taken.
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TEXT CONTINUATION ig?,yo*A!5,Wi*oja@tMQ'"Vl2'u".'OENU Si"t,V. "JJ "tRlNa'Reic?"Jan tWi g 0F MANAGE Mt NT AND SVDGtTA ASHINGTON. DC 20603
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o19 n19 0' nla tarvin, . w . - w ,- ame. inn ELAHI_AND_EYEIEti_IDENIIEICA1108 General Electric - Boiling Water Reactor Energy Industry Identification System (EIIS) codes are identified in the text as (xx).
IDENTIFICATION OF THE EVENT Electrical Noise on the Isolated Ground System (IGS) resulted in High Energy Line Break Isolation Logic (IJ) initiations.
Event Date: 12/21/87, 01/06/88, 03/30/88 Report Date: 5/16/90 l t
CQHDlIl0HS_EB10R_IQ_IEE_EYEHI Operational Condition 4 (Cold Shutdown)
Mode Switch - Shutdown RPV Pressure : O psig RPV Temperature = 112, 113, 114 degrees F POWER LEVEL - 0 ,
I i
All rods' inserted in the core !
I DESCRIPTION OF_IHE_EYEHI l On three separate occasions, High Energy Line Break Logic Isolations of the Reactor Water Clean-up (RWCU) System [CE) and Main Stean, Line
-(MSL) Drain Valves (1G33*MOV-034 and 1B21*MOV-032) occurred nost likely due to high amplitude electrical noise on the IGS. The first i two events occurred on December 21, 1987 and January 6, 1988 at 1633 :
cnd 0825 respectively. Investigation into the events at the time revealed that a grounding problem existed in the Primary Containment Monitoring Panel (1H11*PNL-PCM) where the system Temperature ,
Monitoring Units-(TMUs) (1G11*TMU-500A and 500B) are located. It was believed that the problem was due to the 24 VDC power supplies for the TMUs being grounded to the station ground, and the TMUs being grounded to the IGS. Voltage measurements of potential between the two grounds revealed that an electrical noise potential oxisted, which could have lead to the false signals being generated within the TMUs and in turn, initiate the isolations. An cngineering change was implemented which caused the 24 VDC power i supplies for the TMUs to be grounded to the IGS. This was discussed with the vendor (Rosemount) and was expected to alleviate the problem.
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ol ? nl2 m, m - . -.c , -nm On March 30,1988 at 0845, a third event occurred with identical results. In all three events, Operators verified the signals as .
false and returned the systems to their configurations prior to the '
event. Plant Management was informed of each event and the NRC was notified at 1753 on December 21, 1987, 1058 on January 6, 1988 and 1055 on March 30, 1988.
Similar ocevrrences in June of 1985 were reported via LER 85-023.
Those events were attributed to electromagnetic interferences due to work activities, but could not be repeated after testing. It is now believed that those isolations were also due to the same grounding problem.
CAUSE_DE_IHE_.EYEH.T The apparent cause of the event is that the electrical noise level on the IGS ground was and is such that periodic voltage spikes of large magnitudes trigger the misoperation of the TMUs (Rosemount Analog Trip Units), thereby causing the isolations. A contributing cause for the first two events was believed to be the grounding problem of the TMUs in the PCM panel, but this problem has since been corrected.
ANALYSIS OF THE_ EVENT These events were the unplanned actuations of an Engineered Safety Feature (ESF). There was no safety significance to the events. The high energy line break isolation logic performed as designed by initiating isolations of various systems. The improper grounding of the TMU power supply would affect only those valves that are open.
Had this event occurred under a more severe set of circumstances (5%
power), there would still be no safety significance.
CORRECTIVE ACTIONS
- 1. The grounding scheme for the TMU power supplies was changed to place the power supply and the instrument on the isolated instrument ground.
- 2. An inspection of other similar panels revealed that the grounding problem with the PCM Panel 24 VDC power supplies was an isolated case.
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- 3. Because of the sensitivity of the Analog Trip Units to plant fault currents, a modification to their grounding circuits was prepared which will provide a " cleaner" isolated ground path.
- 4. To further reduce noise and voltage transients on the Instrument Grounding System, modifications were prepared to rewire the neutrals for two transformers such that they would be connected to the Station Ground instead of the Instrument Ground System. Also a modification was prepared to connect the Instrument Ground System buried ground rod to the Station Ground Network, i
Implementation of the above modifications has been deferred indefinitely due to the New York State - LILCO Shoreham Settlement :
Agreement. l, ADDITIONAL _lNFORMAI1QB
- a. Manufacturer and_medel_ number _nLiailed_comnonent_Lal N/A
- b. LEB_ numbers _of_nrexious similar_. events85-023 teaC ,orm ansa (6401
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05000322/LER-1987-009 | LER 87-009-01:on 870203,full Reactor Trip Occurred Due to Perturbation in Ref Leg.Caused by Spurious Low Level Reactor Pressure Vessel Water Level Signal.Existing Level & Pressure Transmitters Replaced W/Newer Models | | 05000322/LER-1987-012 | LER 87-012-01:on 870504,uplanned Actuation of ESF Occurred. Caused by Technician Loosing Footing & Accidently Hitting Outside Cover of Level Switch.Permanent Ladders & Platforms Installed at Head Tank Level Switches | | 05000322/LER-1987-014, Forwards LER 87-014 & Rev 1 to LER 86-029 | Forwards LER 87-014 & Rev 1 to LER 86-029 | | 05000322/LER-1987-022 | LER 87-022-01:on 870604,HPCI Test Valve to Condensate Storage Tank,Globe Valve & Hpci/Rcic Test Valve to Condensate Storage Tank Failed to Close Against Sys Operating Pressure.Disc of motor-operated Valve 37 Modified | | 05000322/LER-1987-035 | LER 87-035-02:on 871221,880106 & 0330,high Energy Line Break Logic Isolations of RWCU & Main Steam Line Drain Valves Occurred.Caused by Problems W/Temp Monitoring Units. Grounding Scheme Changed & Transformers Rewired | |
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