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Issue date | Title | Topic | |
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ML20084R517 | 20 March 1975 | AO 50-249/75-15:on 750310,during Routine Surveillance of Pressure Switch PS3-263-52A-2,setpoint Found Below Tech Spec Limits.Caused by Inherent Setpoint Drift.Switch Trip Point Reset | |
ML20084R535 | 18 March 1975 | AO 50-249/75-14:on 750310,operator Heard Air Blowing Inside Diesel Generator Which Revealed Air Receiving Tank Outlet Valves Closed & Generator Inoperable.Caused by Personnel Error.Operability Check Changed | |
ML20084R577 | 12 March 1975 | AO 50-249/75-13:on 750302,control Rod Drive Scram Times Failed to Meet Limiting Condition for Operation Per Tech Specs.Caused by Deterioration of Drive Seals.Five Questionable Drives Scheduled for Retesting | |
ML20084R586 | 7 March 1975 | AO 50-249/75-09:on 750228,during MSIV Not Full Open Scram Test,Relay 590-102B Failed to Deenergize.Apparently Caused by Faulty Limit Switch on 3-203-2A Msiv.Fuse 590-702B Removed,Placing Sys in Fail Safe Condition | |
ML20084R602 | 27 February 1975 | AO 50-249/75-08:on 750218,during Routine Calibr of Level Switch LIS 3-263-57B,setpoint Found Above Tech Spec Limit. Caused by Instrument Setpoint Drift.Switch Tested for Repeatability & Performed within Manufacturer Limits | |
ML20084R645 | 17 January 1975 | RO 50-249/75-04:on 750107,pin Hole Leak Discovered in Reactor Feed Pump 3B Min Flow Line to Condenser.Caused by Swirl Being Created by Velocity Change Through off-set Reducer.Failed Section of Pipe Isolated & Repaired | |
ML20084R723 | 9 January 1975 | AO 50-249/75-02:on 750103,concentration of Chloride Ions in Reactor Coolant Determined Above Limiting Condition for Operation,Per Tech Specs.Caused by Inoperability of Reactor Coolant Cleanup Sys.Shutdowm Immediately Initiated | |
ML20084R737 | 7 January 1975 | Telecopy Ao:On 750107,during Control Rod Pattern Alteration, Xexon Transient Experienced.Apparently Caused by Fuel Clad Failure in Lower Region of Core | |
ML20084R739 | 16 January 1975 | AO 50-249/75-01:on 750104,insp of Bergen-Paterson Shock Suppressors Revealed Eight Snubbers Low on Oil W/Two Considered Inoperable.Caused by Pinched O-rings,slight Deterioration of Seals & Scratched Cylinder | |
ML20084R768 | 6 December 1974 | AO 50-249/74-37:on 741201,during Routine Plant Insp,Pin Hole Leak Found on Min Flow Line.Caused by Erosion of Pipe from Within.Pipe Isolated & Leak Repaired Using Certified Welding Matls & Techniques | |
ML20084R788 | 6 December 1974 | AO 50-249/74-36:on 741201,small Leak Discovered on Reactor Feed Pump 3A Min Flow Line 3-3205A.Caused by Erosion of Pipe.Leaking Pipe Isolated & Repaired by Welding | |
ML20084R813 | 4 October 1974 | AO 50-249/74-47:on 740927,waste Collector Filter Pressure Switch Taps B Failed During Backwash Cycle.Lines B Bumped & Jarred During Maint on Unit A.Failed Lines Isolated | |
ML20084R840 | 22 July 1974 | AO 50-249/74-37:on 740716,torus Oxygen Concentration Above 4% After 24 H.Caused by Nitrogen Supplier Failing to Meet Delivery.Vendor Notified & Util Advised That Original Order Had Been Lost | |
ML20084R851 | 12 December 1974 | AO 50-249/74-35:on 741130,reactor Bldg Exhaust Fans 3A & B Tripped Off & Would Not Reset & Secondary Containment Blowout Panel Failed.Apparently Caused by Reactor Bldgs Becoming Overpressurized.Unit Shut Down | |
ML20084R853 | 19 November 1974 | AO 50-249/74-34:on 741109,while Placing Offgas Recombiner 3A in Svc,Air Ejector Rupture Disc 3A Failed.Caused by Detonation of Offgas Which Occurred When Recombiner Outlet Valve 3A Was Opened.Steam Jet Air Ejectors Changed | |
ML20084R866 | 9 October 1974 | AO 50-249/74-32:on 741003,high Pressure Coolant Injection High Flow Switch DPIS 3-2352 Found W/Setpoint Above Tech Spec Limit.Caused by Setpoint Drift.Switch Repaired & Reset | |
ML20084R874 | 8 October 1974 | AO 50-249/74-31:on 740928,core Height Water Level Sensors Lits 3-263-73 a & B Found W/Setpoints Above Tech Spec Limit. Apparently Caused by Trapped Air Bubbles in Sensor or Not Considering Instrument Hysteresis | |
ML20084R943 | 2 October 1974 | AO 50-249/74-29:on 740924,through-wall Crack Discovered on Torus/Drywell Purge Line.Cause Unknown.Segment Cut Out of Line Containing Crack & New Pipe Segment Welded in Place | |
ML20084R951 | 26 September 1974 | AO 50-249/74-28:on 740920,leakage Noted in Feedwater Line Pressure Tap 3-3241-12A.Caused by Crack in Weld.Pressure Tap No Longer Used | Time of Discovery |
ML20084R973 | 16 September 1974 | AO 50-249/74-28:on 740908,following Transversing in-core Probe (TIP) Scans,Ball Isolation Valve on TIP Machine 3E Failed to Close as Indicated by Light on Control Panel. Caused by Weak Closure Spring.Plant Mod Initiated | |
ML20084R999 | 3 September 1974 | AO 50-249/74-27:on 740928,following Surveillance of Core Spray Sys,Core Spray 3A Discharge Header Pressure Was Lost. Caused by Discharge Stop Check Valve 3-1402-8A Failure to Seat Properly.Valve Manually Cycled | |
ML20084S028 | 19 August 1974 | AO 50-249/74-25:on 740807,ball Isolation Valve on Transversing in-core Probe Machine B Failed to Close.Caused by Broken Wire on Solenoid Coil Actuator.Top Actuator of Valve Replaced | |
ML20084S051 | 1 August 1974 | AO 50-249/74-23 & 24:on 740726,during Insp Prior to Local Leak Rate Testing,Rubber Coated Valve Seat for AO-3-1601-21 & 22 Found Cracked.Caused by Liquid Nitrogen Reaching Both Valves.Valve AO-3-1601-21 Replaced & 22 Blank Flanged | |
ML20084S274 | 20 March 1973 | Telecopy Ao:On 730320,waste Surge in Grand Tanks Sampled & Activity Found to Be Above Tech Spec Limit.Caused by Pumping Waste Collector Water Directly to Surge Tank. Procedures Will Be Reviewed & Revised to Eliminate Problem | |
ML20084S367 | 17 January 1975 | AO 50-249/74-38:on 741031,excessive Power Peaking Observed in Lower Region of Core.Caused by Xenon Transient Combined W/Very Low Fuel Exposure at Core Bottom.Control Rod Withdrawn | Power change |
ML20084T882 | 15 June 1970 | Ao:On 700605,turbine electro-hydraulic Control Sys Transient Caused Turbine Trip & Reactor Scram,Followed by Inadvertently Opened Safety Valves.Two Safety Valves Failed to Close,Releasing Primary Coolant to Containment | |
ML20084U014 | 2 June 1970 | Ao:On 700529,piping Restraints & Supports Damaged.Caused by Displaced HPCI Steam Line Beyond Outboard Isolation Valve. HPCI Outage Time Extension Requested | |
ML20084U950 | 2 January 1975 | AO 50-265/74-29:on 741223,cracks at Welds in 4 Inch Reactor Recirculation Discharge Valve Bypass Lines Indicated.Cause Undetermined.Piping on a & B Loops to Be Completely Replaced | |
ML20084U956 | 23 December 1974 | Telecopy Ao:Three Weld Abnormalities Discovered on Welds in Bypass Piping Lines Around Recirculation Pump Discharge Valves.Plans Formulated to Replace Lines | |
ML20085E955 | 9 July 1975 | AO BFAO-50-260/759T:on 750709,broken Stem Found on second- Stage Pilot of Main Steam Release Valve 1.Break Point Just Under Lock Nut Above Actuating Piston.Site Inspector Advised | |
ML20085G186 | 24 October 1973 | Ao:On 730925,trip Setpoint of 152 Inches for HPCI Flow Switch DPIS 3-2353 Exceeded Tech Spec Limit.Caused by Locking Device Failing to Control Setpoint Drift.Switch Setpoint Changed & Calibr Frequency Increased | |
ML20085G188 | 26 October 1973 | AO BFAO-7327W:on 731016,setpoint of 1.8 Psid for Recirculation Jet Pump Riser Differential Pressure Switch PdIS-68-24 Exceeded Tech Spec Limit.Switch Recalibr,Tested & Frequency Increased to Once Every 2 Wks | |
ML20085G823 | 18 September 1973 | AO BFAO-739W:on 730908,fuse Blew in Power Supplying HPCI Inverter Power Supply.Caused by Generic Problem W/Inverter. Fuse Replaced & Manufacturer Making Changes to Inverter Model | |
ML20085J815 | 2 July 1974 | Ao:On 740623,severe Vibrations Experienced on Feedwater Sys, Resulting in Damage to Feedwater Regulation Valves & Pipe Restraints.Cause Unknown.Piping Repaired.Investigation Continuing | |
ML20085J827 | 19 June 1974 | Ao:On 740611,two Reactor High Pressure Scram Switches Found W/Setpoints Above Tech Spec Limit.Caused by Instrument Drift.Program in Progress to Precondition All Barksdale & Meletron Bourdon tube-type Switches | |
ML20085J839 | 18 June 1974 | Ao:On 740611,during Unit Startup Small Leak Detected in Line 3-3037B Which Supplies Steam to Recombiner Booster Jet B.Caused by Defective Weld.Area Rewelded | |
ML20085J848 | 18 June 1974 | Ao:On 740610,leak Discovered in Newly Installed Vibration Test Line Located on Reactor Feedwater Pump Discharge Header.Caused by Crack on Side of Nipple of Test Line.Unit Shut Down to Repair Leak | Hydrostatic |
ML20085J858 | 10 June 1974 | Ao:On 740605,HPCI Valve 3-2301-3 Failed to Open.Caused by Lack of Clearance Between Auxiliary Contact Operating Bar & Main Contact Armature Roller.Air Gap Adjusted | |
ML20085J865 | 12 June 1974 | Ao:On 740604,during Functional Test on Main Steam Line Radiation Monitor D,Trip & Alarm Did Not Function.Cause Unknown.Monitor Replaced | |
ML20085J870 | 12 June 1974 | Ao:On 740603,during Routine Surveillance of Low Pressure Trip Switches PS2389 A,B,C & D Found W/Setpoints Above Tech Spec Limit.Caused by Lack of Precycling Prior to Installation.Switches Will Be Returned to Factory | |
ML20085J880 | 31 May 1974 | Ao:On 740523,during Routine Monthly Surveillance 2/3 Core Height Water Level Sensor Lits 3-263-73A Found to Have Setpoint Above Tech Spec Limit.Caused by Setpoint Drift. Switch Reset | |
ML20085J894 | 21 June 1974 | Ao:On 740522,main Steam Line Drain Valve 3-220-2 Failed to Operate Correctly.Caused by Burned Armature Windings in Valve Motor.Motor Replaced | |
ML20085J903 | 23 May 1974 | Ao:On 740515,during Scheduled Refuel Surveillance All 16 Main Steam Line Temp Sensors Found to Operate Above Tech Spec Limit.Caused by Incorrect Calibr Technique.Corrective Action Dependent on Vendor Response to Problems | |
ML20085J922 | 21 May 1974 | Ao:On 740515,during Local Leak Rate Testing of Msivs,Valves 1B & 2B Found W/Leak Rate Above Allowable Limit.Caused by Warped Valve Seat & Hairline Cracks in Stellate Overlay on Disc.Seating Surfaces of 2B Reinstalled | |
ML20085J938 | 13 May 1974 | Ao:On 740506,during Local Leak Rate Testing of Feedwater Check valves,3-220-58B & 3-220-62B Revealed Leakage in Excess of Tech Spec Limit.Caused by O-ring Being Out of Groove.Ring Replaced | |
ML20085J951 | 6 May 1974 | Ao:On 740427,after Rejection of Water Commenced,Torus Level Indication Increased.Operator Tapped on Impulse Lines of Transmitter & Indication Returned to Actual Level. Transmitter Calibr | |
ML20085J968 | 11 June 1974 | Ao:Supplemental Info to Deviation Rept D-12-3-74-10 Re 3B Control Rod Drive Water Filter Drain Line.Normal Maint Insps & Sys Operational Tests Adequate to Prevent or Minimize Such Failures | |
ML20085J972 | 4 April 1974 | Ao:On 740402,during Normal Plant Insp,Minor Leak Found in Control Rod Drive Water Filter 3B-302-4 Drain Line.Caused by Cracked Weld Due to Fatigue Failure.Crack Repaired | |
ML20085J982 | 2 April 1974 | Telecopy Ao:On 740402,leakage Discovered on Control Rod Drive Water Filter 3B.Caused by Cracked Drain Line 3-4802B. Repair Procedure Initiated | |
ML20085J986 | 3 April 1974 | Ao:On 740325,during Refueling Surveillance,Eight of 16 Area Temp Switches for HPCI Found W/High Operating Points.Cause Not Found.Calibr Kit on Order from Manufacturer |