PNO-V-87-025, on 870321,facility Experienced Safety Injection,Reactor Trip & Unit Trip.Caused by Coincidence of High Steam Flow & Low Steam Generator Pressure Signals Due to Closure of MSIV FCV 41.Piping & Valve Switches Inspected
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| ML20205G695 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 03/23/1987 |
| From: | Mendonca M, Narbut P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| References | |
| PNO-V-87-025, PNO-V-87-25, NUDOCS 8703310520 | |
| Download: ML20205G695 (1) | |
Similar Documents at Diablo Canyon | |
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Category:PRELIMINARY NOTIFICATION OF EVENT OR OCCURRENCE (PNO
MONTHYEARPNO-V-93-013, on 930809,during pre-announced anti-nuclear demonstration,13 Protestors Illegally Entered Plant Access Gate & Immediately Taken Into Custody by Sheriff Deputies. Demonstration Related to CP Recapture Hearings for Plant1993-08-0909 August 1993
[Table view]PNO-V-93-013:on 930809,during pre-announced anti-nuclear demonstration,13 Protestors Illegally Entered Plant Access Gate & Immediately Taken Into Custody by Sheriff Deputies. Demonstration Related to CP Recapture Hearings for Plant PNO-V-92-033, on 921019,US Geological Survey Notified California Governor Ofc of Significant Likelihood That Earthquake of Magnitude 6 Will Occur on San Andreas Fault Near Parkfield1992-10-20020 October 1992 PNO-V-92-033:on 921019,US Geological Survey Notified California Governor Ofc of Significant Likelihood That Earthquake of Magnitude 6 Will Occur on San Andreas Fault Near Parkfield PNO-V-91-003, on 910307,unit 1 Shutdown for Refueling Operations & Loss of Offsite Power.Licensee Personnel Manually Moved New Module,Still in Mast,Away from Reactor Vessel & Core1991-03-0707 March 1991 PNO-V-91-003:on 910307,unit 1 Shutdown for Refueling Operations & Loss of Offsite Power.Licensee Personnel Manually Moved New Module,Still in Mast,Away from Reactor Vessel & Core PNO-V-90-033, on 900726,observed Crack in Charging Pump Suction Header Piping Caused by Boric Acid Crystals on Elbow of Pump.Licensee Considers Piping Operable & to Be Repaired W/O Plant Shut Down.Inspector Monitoring Plant1990-07-27027 July 1990 PNO-V-90-033:on 900726,observed Crack in Charging Pump Suction Header Piping Caused by Boric Acid Crystals on Elbow of Pump.Licensee Considers Piping Operable & to Be Repaired W/O Plant Shut Down.Inspector Monitoring Plant PNO-V-88-048, on 880717,unit Manually Tripped & Natural Cooldown Commenced as Result of Ground Fault in 12 Kv non- Vital Buses.Event Investigation Team Formed to Determine Location & Cause of Ground Fault1988-07-18018 July 1988 PNO-V-88-048:on 880717,unit Manually Tripped & Natural Cooldown Commenced as Result of Ground Fault in 12 Kv non- Vital Buses.Event Investigation Team Formed to Determine Location & Cause of Ground Fault PNO-V-87-083, on 871213,reactor Tripped.Caused by Loss of Feed Water Pump 1-1.Cause of Trip Under Investigation. Variety of Maint Activities to Be Performed Before Restart1987-12-14014 December 1987 PNO-V-87-083:on 871213,reactor Tripped.Caused by Loss of Feed Water Pump 1-1.Cause of Trip Under Investigation. Variety of Maint Activities to Be Performed Before Restart PNO-V-87-082, on 871210,fire Occurred in Temporary Tool Storage Trailer in Vicinity of Unit 2 Main Generator Transformers.Caused by 120 Volt Junction Box,Possibly Overloaded from Portable Space Heater.Fire Put Out1987-12-10010 December 1987 PNO-V-87-082:on 871210,fire Occurred in Temporary Tool Storage Trailer in Vicinity of Unit 2 Main Generator Transformers.Caused by 120 Volt Junction Box,Possibly Overloaded from Portable Space Heater.Fire Put Out PNO-V-87-074, on 871110,county Inadvertently Actuated Emergency Notification Sys(Sirens).Caused by Wrong Sequence Being Entered Into Sys While Performing Weekly Silent Test. Corrective Action Under Investigation1987-11-10010 November 1987 PNO-V-87-074:on 871110,county Inadvertently Actuated Emergency Notification Sys(Sirens).Caused by Wrong Sequence Being Entered Into Sys While Performing Weekly Silent Test. Corrective Action Under Investigation PNO-V-87-073, on 871107,unit Trip Manually Initiated.Caused by Failure of motor-operated Disconnect in Main Generator 25 Kv Isophase Bus C.Repair & Unit Outage Will Take Between 2 Wks & 2 Months,Depending on Availability of Parts1987-11-0909 November 1987 PNO-V-87-073:on 871107,unit Trip Manually Initiated.Caused by Failure of motor-operated Disconnect in Main Generator 25 Kv Isophase Bus C.Repair & Unit Outage Will Take Between 2 Wks & 2 Months,Depending on Availability of Parts PNO-V-87-066, on 871006,while Performing Periodic Surveillance Testing of Control Rods at 100% Power,Rod Control Urgent Failure Alarm Received on Shutdown Bank A. Caused by Blown Fuses.Fuses Replaced & Alarm Cleared1987-10-0606 October 1987 PNO-V-87-066:on 871006,while Performing Periodic Surveillance Testing of Control Rods at 100% Power,Rod Control Urgent Failure Alarm Received on Shutdown Bank A. Caused by Blown Fuses.Fuses Replaced & Alarm Cleared PNO-V-87-053, on 870723,high Radiation Alarm Automatically Diverted Liquid Radwaste Flow to Storage Tank.Licensee Determining Root Cause.Chemical Drain Tank Properly Recirculated & Sampled Prior to Discharge Per Procedure1987-07-24024 July 1987 PNO-V-87-053:on 870723,high Radiation Alarm Automatically Diverted Liquid Radwaste Flow to Storage Tank.Licensee Determining Root Cause.Chemical Drain Tank Properly Recirculated & Sampled Prior to Discharge Per Procedure PNO-V-87-051, on 870714,reactor Trip & Safety Injection from 12% Power Occurred.Caused by turbine-generator Trip Due to High Steam Generator Water Level & Flickering High Steam Flow Bistables,Respectively.Root Causes Under Investigation1987-07-14014 July 1987 PNO-V-87-051:on 870714,reactor Trip & Safety Injection from 12% Power Occurred.Caused by turbine-generator Trip Due to High Steam Generator Water Level & Flickering High Steam Flow Bistables,Respectively.Root Causes Under Investigation ML20215F9001987-06-17017 June 1987 PNS-V-87-005:on 870617,American Protective Svc Notified Util That Security Personnel on Strike Over Monetary Benefits. Licensee Capable to Meet Security Staffing Requirements Through Use of Proprietary Security Personnel PNO-V-87-041, on 870602,engineer in Containment Noted Weepage from RHR Sys Line While RHR in Svc.Cause of Effect Undetermined.Licensee Preparing Work Orders to Isolate, Examine & Repair Weld1987-06-0303 June 1987 PNO-V-87-041:on 870602,engineer in Containment Noted Weepage from RHR Sys Line While RHR in Svc.Cause of Effect Undetermined.Licensee Preparing Work Orders to Isolate, Examine & Repair Weld ML20209D5131987-04-23023 April 1987 Updated PNO-V-87-030B:on 870421,onsite Phase of AIT Team Special Insp Into 870410 Loss of Suction to RHR Sys While in half-loop Concluded W/Meeting at Site PNO-V-87-030A, on 870415,Region V Augmented Insp Team Commenced Insp Activities Re 870410 Loss of Suction to RHR While at Half Loop.Team Expects to Stay Onsite Through 870421.Summary of Sequence of Event Encl1987-04-20020 April 1987 PNO-V-87-030A:on 870415,Region V Augmented Insp Team Commenced Insp Activities Re 870410 Loss of Suction to RHR While at Half Loop.Team Expects to Stay Onsite Through 870421.Summary of Sequence of Event Encl PNO-V-87-030, on 870410,RHR Sys Capability Lost for Approx 90 Minutes.Caused by Entrainment of Air within RHR Pumps When RCS Water Level Dropped Due to Water Leakage Through Two Valves.Augmented Insp Team Dispatched1987-04-13013 April 1987 PNO-V-87-030:on 870410,RHR Sys Capability Lost for Approx 90 Minutes.Caused by Entrainment of Air within RHR Pumps When RCS Water Level Dropped Due to Water Leakage Through Two Valves.Augmented Insp Team Dispatched PNO-V-87-028, on 870403,reactor Tripped from 12% Power During Shut Down for First Refueling Outage.Caused by Flicker of High Steam Flow Bistables Coincident w/lo-lo T Average.Investigation Continuing1987-04-0606 April 1987 PNO-V-87-028:on 870403,reactor Tripped from 12% Power During Shut Down for First Refueling Outage.Caused by Flicker of High Steam Flow Bistables Coincident w/lo-lo T Average.Investigation Continuing PNO-V-87-025, on 870321,facility Experienced Safety Injection,Reactor Trip & Unit Trip.Caused by Coincidence of High Steam Flow & Low Steam Generator Pressure Signals Due to Closure of MSIV FCV 41.Piping & Valve Switches Inspected1987-03-23023 March 1987 PNO-V-87-025:on 870321,facility Experienced Safety Injection,Reactor Trip & Unit Trip.Caused by Coincidence of High Steam Flow & Low Steam Generator Pressure Signals Due to Closure of MSIV FCV 41.Piping & Valve Switches Inspected PNO-V-87-018, on 870301,1-2 Mw/Min Shutdown Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak. Vibration,Induced by Main Generator,Caused Cracking in Welds of Stator Cooling Water Sys Which Occurred on 8702171987-03-0202 March 1987 PNO-V-87-018:on 870301,1-2 Mw/Min Shutdown Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak. Vibration,Induced by Main Generator,Caused Cracking in Welds of Stator Cooling Water Sys Which Occurred on 870217 PNO-V-87-016, on 870221,shutdown Commenced Due to Train B of Solid State Protection Sys Not Returning to Svc within 2 H. Caused by High Steam Generator Level on Generator 1-4 & Feedwater Flow Instabilities & Valve Position Problem1987-02-23023 February 1987 PNO-V-87-016:on 870221,shutdown Commenced Due to Train B of Solid State Protection Sys Not Returning to Svc within 2 H. Caused by High Steam Generator Level on Generator 1-4 & Feedwater Flow Instabilities & Valve Position Problem PNO-V-87-014, on 870217,slow Shutdown from 100% Power Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak.Caused by Cracking in Stator Water Cooling Vent Line Due to Vibration.Outage Expected to Last Approx 1 Wk1987-02-18018 February 1987 PNO-V-87-014:on 870217,slow Shutdown from 100% Power Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak.Caused by Cracking in Stator Water Cooling Vent Line Due to Vibration.Outage Expected to Last Approx 1 Wk PNO-V-87-002, on 870105,reactor Trip/Turbine Trip Occurred. Caused by Loss of Turbine Governor/Stop Valve electro- Hydraulic Sys Pressure,Attributed to Leak in Compression Fitting Connection to Steam Lead Stop Valve FCV-1451987-01-0606 January 1987 PNO-V-87-002:on 870105,reactor Trip/Turbine Trip Occurred. Caused by Loss of Turbine Governor/Stop Valve electro- Hydraulic Sys Pressure,Attributed to Leak in Compression Fitting Connection to Steam Lead Stop Valve FCV-145 PNO-V-87-001, on 870102,licensee Shut Down Plant.Caused by Fire Near High Pressure Turbine Front Bearing.Licensee Affected Repairs & Examining Bearing Area for Any Signs of Oil Leak1987-01-0505 January 1987 PNO-V-87-001:on 870102,licensee Shut Down Plant.Caused by Fire Near High Pressure Turbine Front Bearing.Licensee Affected Repairs & Examining Bearing Area for Any Signs of Oil Leak PNO-V-86-089, on 861207,plant Seismic Monitor Detected Ground Motion Which Triggered Ripplemental Seismic Monitoring Sys.Ground Motion Measured 2.9 on Richter Scale1986-12-0808 December 1986 PNO-V-86-089:on 861207,plant Seismic Monitor Detected Ground Motion Which Triggered Ripplemental Seismic Monitoring Sys.Ground Motion Measured 2.9 on Richter Scale PNO-V-86-074, on 861028,main Steam Valves Found W/Missing & Loosened Nuts That Secure Valve Disc to Hinge Arm. Deficiencies Discovered During Visual Exam as Part of Inservice Testing Exam1986-10-30030 October 1986 PNO-V-86-074:on 861028,main Steam Valves Found W/Missing & Loosened Nuts That Secure Valve Disc to Hinge Arm. Deficiencies Discovered During Visual Exam as Part of Inservice Testing Exam PNO-V-86-075, on 861029,during Followup Insp of Accumulator Drain Fittings,Pin Hole Leaks Discovered in Accumulators 2-2 & 2-4 in Nonwelded Portion of Fitting.Cause Not Stated.Leaks Repaired1986-10-30030 October 1986 PNO-V-86-075:on 861029,during Followup Insp of Accumulator Drain Fittings,Pin Hole Leaks Discovered in Accumulators 2-2 & 2-4 in Nonwelded Portion of Fitting.Cause Not Stated.Leaks Repaired PNO-V-86-073, GL Mcchain,In Custody by FBI on Parole Violation,Issued Claims of Evading Security Background Checks for 6 Yrs While Working at Listed Facilities & Knows of Falsified Weld Records.Investigation in Progress1986-10-23023 October 1986 PNO-V-86-073:GL Mcchain,In Custody by FBI on Parole Violation,Issued Claims of Evading Security Background Checks for 6 Yrs While Working at Listed Facilities & Knows of Falsified Weld Records.Investigation in Progress PNO-V-86-070, on 861004,discovered Two Snubbers on Charging Sys Mistakenly Removed.Charging Sys Required by Tech Specs for Refueling Boration Flow Path.Snubbers Reinstalled within Hour of Discovery1986-10-0606 October 1986 PNO-V-86-070:on 861004,discovered Two Snubbers on Charging Sys Mistakenly Removed.Charging Sys Required by Tech Specs for Refueling Boration Flow Path.Snubbers Reinstalled within Hour of Discovery PNO-V-86-067, on 861001,fuel Assembly in Vessel Found W/ 10-degree Tilt & Resting Askew Against Core Baffle Plate. Cause Under Investigation.Program & Special Tools Prepared to Return Assembly to Vertical Position1986-10-0101 October 1986 PNO-V-86-067:on 861001,fuel Assembly in Vessel Found W/ 10-degree Tilt & Resting Askew Against Core Baffle Plate. Cause Under Investigation.Program & Special Tools Prepared to Return Assembly to Vertical Position PNO-V-86-065, on 860918,reactor Tripped Due to Loss of Main Feedwater Pump 2-2 During Maint on Lovejoy Speed Controller Sys.Caused by Steam Flow/Feed Flow Mismatch Coincident W/Low Level on Steam Generators 2 & 4.Cause Under Investigation1986-09-18018 September 1986 PNO-V-86-065:on 860918,reactor Tripped Due to Loss of Main Feedwater Pump 2-2 During Maint on Lovejoy Speed Controller Sys.Caused by Steam Flow/Feed Flow Mismatch Coincident W/Low Level on Steam Generators 2 & 4.Cause Under Investigation PNO-V-86-062, court Decided in Favor of San Luis Obispo Mothers for Peace & Sierra Club Re Spent Fuel Pool Expansion.Util Reinstalling Old Racks & May Use Spent Fuel Pools Prior to Completion of New Hearings1986-09-12012 September 1986 PNO-V-86-062:court Decided in Favor of San Luis Obispo Mothers for Peace & Sierra Club Re Spent Fuel Pool Expansion.Util Reinstalling Old Racks & May Use Spent Fuel Pools Prior to Completion of New Hearings PNO-V-86-056, on 860829,first Refueling Outage Began.Work to Include Copper Reduction & court-ordered Replacement of New High Density Fuel Racks W/Older Low Density Fuel Racks1986-08-29029 August 1986 PNO-V-86-056:on 860829,first Refueling Outage Began.Work to Include Copper Reduction & court-ordered Replacement of New High Density Fuel Racks W/Older Low Density Fuel Racks PNO-V-86-057, reactor Trip Occurred.Caused by Loose Wire on Shunt Coil Relay That Shorted During Surveillance Testing & Opened Reactor Trip Breaker.New High Density Fuel Racks Removed & Older Low Density Racks Reinstalled1986-08-29029 August 1986 PNO-V-86-057:reactor Trip Occurred.Caused by Loose Wire on Shunt Coil Relay That Shorted During Surveillance Testing & Opened Reactor Trip Breaker.New High Density Fuel Racks Removed & Older Low Density Racks Reinstalled PNO-V-86-046, on 860721,two Seismic Events Occurred in Mammoth Lakes Area.Largest Event Measured 6.2 on Richter Scale & Second Measured 4.4.First Event Not Felt at Diablo Canyon.Second Event Triggered Teratec Recording1986-07-21021 July 1986 PNO-V-86-046:on 860721,two Seismic Events Occurred in Mammoth Lakes Area.Largest Event Measured 6.2 on Richter Scale & Second Measured 4.4.First Event Not Felt at Diablo Canyon.Second Event Triggered Teratec Recording PNO-V-86-040, on 860709,reactor Tripped Due to Low Level in Steam Generator Coincident W/Steam Flow Feed Flow Mismatch. Caused by Loss of Main Feed Pump.Pump Repaired & post-trip Review Conducted1986-07-10010 July 1986 PNO-V-86-040:on 860709,reactor Tripped Due to Low Level in Steam Generator Coincident W/Steam Flow Feed Flow Mismatch. Caused by Loss of Main Feed Pump.Pump Repaired & post-trip Review Conducted PNO-V-86-038, on 860703,facility Experienced Reactor Trip & Safety Injection Due to Momentary High Steam Flow Coincident w/lo-lo Tavg Signal from solid-state Protection Sys.On 860706,second Turbine & Reactor Trip Experienced1986-07-0707 July 1986 PNO-V-86-038:on 860703,facility Experienced Reactor Trip & Safety Injection Due to Momentary High Steam Flow Coincident w/lo-lo Tavg Signal from solid-state Protection Sys.On 860706,second Turbine & Reactor Trip Experienced PNO-V-86-027, on 860505,diesel Generator Unexpectedly Started & Loaded on Vital Bus G Undervoltage Condition.Auxiliary Feeder Breaker Tripped on Overcurrent & Startup Power Feeder Breaker Did Not Close In.Investigation Underway1986-05-0707 May 1986 PNO-V-86-027:on 860505,diesel Generator Unexpectedly Started & Loaded on Vital Bus G Undervoltage Condition.Auxiliary Feeder Breaker Tripped on Overcurrent & Startup Power Feeder Breaker Did Not Close In.Investigation Underway PNO-V-86-019, on 860418,unusual Event Declared on Initiation of Shutdown.On 860417,problems W/Computer Info from in-core Instrumentation for Quadrant Power Tilt Ratio Measurement Occurred1986-04-18018 April 1986 PNO-V-86-019:on 860418,unusual Event Declared on Initiation of Shutdown.On 860417,problems W/Computer Info from in-core Instrumentation for Quadrant Power Tilt Ratio Measurement Occurred PNO-V-86-013, on 860330,while Reducing Power Due to Indications of Condenser Tube Rupture,Operator Initiated Manual Unit Trip Resulting in Safety Injection on High Steam Flow & lo-lo Tavg.Caused by Switch Problem & Stuck Valve1986-03-31031 March 1986 PNO-V-86-013:on 860330,while Reducing Power Due to Indications of Condenser Tube Rupture,Operator Initiated Manual Unit Trip Resulting in Safety Injection on High Steam Flow & lo-lo Tavg.Caused by Switch Problem & Stuck Valve PNO-V-86-011, on 860314,during Main Turbine Testing,Safety Injection & Reactor Trip Occurred from High Steam Flow Signal.Plant Stabilized.Licensee Will Resume Operations Once Event Evaluated & Excess Boron Removed1986-03-14014 March 1986 PNO-V-86-011:on 860314,during Main Turbine Testing,Safety Injection & Reactor Trip Occurred from High Steam Flow Signal.Plant Stabilized.Licensee Will Resume Operations Once Event Evaluated & Excess Boron Removed PNO-V-86-010, on 860312,reactor Brought Critical Following Negative Rate Trip During Net Load Startup Test on 860311. Reactor Declared in Commercial Operation on 8603131986-03-13013 March 1986 PNO-V-86-010:on 860312,reactor Brought Critical Following Negative Rate Trip During Net Load Startup Test on 860311. Reactor Declared in Commercial Operation on 860313 PNO-V-86-008, on 860219,unusual Event Declared & Hot Shutdown Initiated After Boron Sample Exceeded 2,200 Ppm.Unusual Event Terminated When Primary Std for Boron Analysis Determined to Be Faulty1986-02-20020 February 1986 PNO-V-86-008:on 860219,unusual Event Declared & Hot Shutdown Initiated After Boron Sample Exceeded 2,200 Ppm.Unusual Event Terminated When Primary Std for Boron Analysis Determined to Be Faulty PNO-V-86-001, on 860102,unusual Event Declared When Reactor Tripped on lo-lo Steam Generator Level Following Feedwater Pump Trip.Caused by Reactor Coolant Pumps Tripping on Undervoltage.Pumps Restarted in 3 to 5 Minutes1986-01-0303 January 1986 PNO-V-86-001:on 860102,unusual Event Declared When Reactor Tripped on lo-lo Steam Generator Level Following Feedwater Pump Trip.Caused by Reactor Coolant Pumps Tripping on Undervoltage.Pumps Restarted in 3 to 5 Minutes PNO-V-85-091, on 851225,during Full Load Rejection Test, Reactor Tripped on lo-lo Steam Generator Level & Coolant Pumps Tripped.Caused by over-responsive Turbine Control Sys & under-responsive Steam Dump Sys.Pumps Restarted1985-12-26026 December 1985 PNO-V-85-091:on 851225,during Full Load Rejection Test, Reactor Tripped on lo-lo Steam Generator Level & Coolant Pumps Tripped.Caused by over-responsive Turbine Control Sys & under-responsive Steam Dump Sys.Pumps Restarted ML20138E1941985-12-0606 December 1985 PNS-V-85-006:on 851206,util Notified NRC of Arrest of Five Individuals,Including Three Plant Security Employees,For Use & Sale of Narcotics During 3-wk Period Ending 851205.No Evidence of Use of Narcotics at Plant Site Identified PNO-V-85-082, on 851202,low Tide Concurrent W/High Seas Caused Kelp to Be Injected Into Condenser Circulating Water Intake Structure.Control RPI Lost & Reactor Manually Tripped.Cause Under Investigation1985-12-0303 December 1985 PNO-V-85-082:on 851202,low Tide Concurrent W/High Seas Caused Kelp to Be Injected Into Condenser Circulating Water Intake Structure.Control RPI Lost & Reactor Manually Tripped.Cause Under Investigation PNO-V-85-081, on 851201,turbine & Reactor Trips Occurred. Caused by High Steam Generator Level Due to Sluggish Automatic Steam Generator Level Control Sys Response.No Safety Injection or ECCS Activated1985-12-0202 December 1985 PNO-V-85-081:on 851201,turbine & Reactor Trips Occurred. Caused by High Steam Generator Level Due to Sluggish Automatic Steam Generator Level Control Sys Response.No Safety Injection or ECCS Activated PNO-V-85-080, on 851128,oscillation of Steam Flow Resulted in Reactor Trip Due to Completion of Steam Generator Low Level Coincident W/Steam Flow/Feedwater Flow Mismatch Logic. Cause Will Be Determined Prior to Resuming Operations1985-11-29029 November 1985 PNO-V-85-080:on 851128,oscillation of Steam Flow Resulted in Reactor Trip Due to Completion of Steam Generator Low Level Coincident W/Steam Flow/Feedwater Flow Mismatch Logic. Cause Will Be Determined Prior to Resuming Operations PNO-V-85-079, on 851126,safety Injection Occurred on High Steam Flow Signal.Cause Under Investigation.Plant Stabilized & Maintaining Hot Standby Conditions.Licensee Plans to Evaluate Data & Make Appropriate Adjustments1985-11-27027 November 1985 PNO-V-85-079:on 851126,safety Injection Occurred on High Steam Flow Signal.Cause Under Investigation.Plant Stabilized & Maintaining Hot Standby Conditions.Licensee Plans to Evaluate Data & Make Appropriate Adjustments 1993-08-09 Category:TEXT-INSPECTION & AUDIT & I&E CIRCULARS MONTHYEARIR 05000275/19990121999-09-13013 September 1999
[Table view]Insp Repts 50-275/99-12 & 50-323/99-12 on 990711-0821. Noncited Violations Noted.Major Areas Inspected:Aspects of Licensee Operations,Maint,Engineering & Plant Support IR 05000275/19990071999-07-27027 July 1999 Insp Repts 50-275/99-07 & 50-323/99-07 on 990503-0714. Apparent Violations Being Considered for Escalated Enforcement Action.Major Areas Inspected:Operations & Engineering IR 05000275/19980161998-11-16016 November 1998 Insp Repts 50-275/98-16 & 50-323/98-16 on 980913-1024.No Violations Noted.Major Areas Inspected:Operations,Maint, Engineering & Plant Support IR 05000275/19980111998-07-22022 July 1998 Insp Repts 50-275/98-11 & 50-323/98-11 on 980526-28.No Violations Noted.Major Areas Inspected:Circumstances, Potential Safety Consequences & Licensee Response & Actions Taken Re Authorization of Tagout W/O Written Procedure IR 05000275/19980081998-04-17017 April 1998 Insp Repts 50-275/98-08 & 50-323/98-05 on 980202-06,23-27 & 0302-18.No Violations Noted.Major Areas Inspected: Engineering IR 05000275/19980031998-01-23023 January 1998 Insp Repts 50-275/98-03 & 50-323/98-03 on 980105-09.No Violations Noted.Major Areas Inspected:Implementation of Solid Radioactive Waste Mgt & Radioactive Matls Transportation IR 05000275/19940271994-12-21021 December 1994 Insp Repts 50-275/94-27 & 50-323/94-27 on 941016-1126. Violations Noted.Major Areas Inspected:Operational Safety Verification,Plant Maint,Surveillance Observation,Plant Support Activities & in-office Review of LERs PNO-V-93-013, on 930809,during pre-announced anti-nuclear demonstration,13 Protestors Illegally Entered Plant Access Gate & Immediately Taken Into Custody by Sheriff Deputies. Demonstration Related to CP Recapture Hearings for Plant1993-08-0909 August 1993 PNO-V-93-013:on 930809,during pre-announced anti-nuclear demonstration,13 Protestors Illegally Entered Plant Access Gate & Immediately Taken Into Custody by Sheriff Deputies. Demonstration Related to CP Recapture Hearings for Plant PNO-V-92-033, on 921019,US Geological Survey Notified California Governor Ofc of Significant Likelihood That Earthquake of Magnitude 6 Will Occur on San Andreas Fault Near Parkfield1992-10-20020 October 1992 PNO-V-92-033:on 921019,US Geological Survey Notified California Governor Ofc of Significant Likelihood That Earthquake of Magnitude 6 Will Occur on San Andreas Fault Near Parkfield PNO-V-91-003, on 910307,unit 1 Shutdown for Refueling Operations & Loss of Offsite Power.Licensee Personnel Manually Moved New Module,Still in Mast,Away from Reactor Vessel & Core1991-03-0707 March 1991 PNO-V-91-003:on 910307,unit 1 Shutdown for Refueling Operations & Loss of Offsite Power.Licensee Personnel Manually Moved New Module,Still in Mast,Away from Reactor Vessel & Core IR 05000275/19900171990-10-22022 October 1990 Partially Withheld Safeguards Insp Repts 50-275/90-17 & 50-323/90-17 on 900924-1008.Noncited Violations Noted.Major Areas Inspected:Physical Security Program PNO-V-90-033, on 900726,observed Crack in Charging Pump Suction Header Piping Caused by Boric Acid Crystals on Elbow of Pump.Licensee Considers Piping Operable & to Be Repaired W/O Plant Shut Down.Inspector Monitoring Plant1990-07-27027 July 1990 PNO-V-90-033:on 900726,observed Crack in Charging Pump Suction Header Piping Caused by Boric Acid Crystals on Elbow of Pump.Licensee Considers Piping Operable & to Be Repaired W/O Plant Shut Down.Inspector Monitoring Plant ML20055J2001990-07-13013 July 1990 Notice of Violation from Insp on 900422-0609.Violations Noted:Work Order Which Provided Instructions for Replacement of Plant Turbine Driven Auxiliary Feedwater Pump Speed Governor Not Appropriate to Circumstances ML20245E9661989-07-31031 July 1989 Partially Withheld Insp Repts 50-275/89-20 & 50-323/89-20 on 890710-18 (Ref 10CFR2.790(d) & 73.21).No Violations Noted.Noncited Violation Noted Re Compensatory Measures. Major Areas Inspected:Physical Security Program IR 05000275/19890121989-04-18018 April 1989 Insp Repts 50-275/89-12 & 50-323/89-12 on 890403-07.No Violations or Deficiencies Noted.Major Areas Inspected: Followup on Previous Insp Findings & Operational Status of Emergency Preparedness Program IR 05000275/19890031989-02-0808 February 1989 Insp Repts 50-275/89-03 & 50-323/89-03 on 890117-26.No Noncompliance Noted.Major Areas Inspected:Nonroutine Events, Followup of Open Items,Radwaste Sys & Radiological Environ Monitoring & Transportation Activities PNO-V-88-048, on 880717,unit Manually Tripped & Natural Cooldown Commenced as Result of Ground Fault in 12 Kv non- Vital Buses.Event Investigation Team Formed to Determine Location & Cause of Ground Fault1988-07-18018 July 1988 PNO-V-88-048:on 880717,unit Manually Tripped & Natural Cooldown Commenced as Result of Ground Fault in 12 Kv non- Vital Buses.Event Investigation Team Formed to Determine Location & Cause of Ground Fault ML20196D6151988-01-27027 January 1988 Exam Rept 50-275/OL-87-02 for Units 1 & 2 on 871208-17.Exam Results:Three Senior Reactor Candidates & Twelve Reactor Operator Candidates Passed Operating & Written Exams ML20234E8071987-12-21021 December 1987 Corrected Notice of Violation from Insp on 861215-19. Violation Noted:Qualification Documentation for Limitorque Motorized Valve Actuators Did Not Establish Similarity Between Installed Actuator & Actuator Tested PNO-V-87-083, on 871213,reactor Tripped.Caused by Loss of Feed Water Pump 1-1.Cause of Trip Under Investigation. Variety of Maint Activities to Be Performed Before Restart1987-12-14014 December 1987 PNO-V-87-083:on 871213,reactor Tripped.Caused by Loss of Feed Water Pump 1-1.Cause of Trip Under Investigation. Variety of Maint Activities to Be Performed Before Restart PNO-V-87-082, on 871210,fire Occurred in Temporary Tool Storage Trailer in Vicinity of Unit 2 Main Generator Transformers.Caused by 120 Volt Junction Box,Possibly Overloaded from Portable Space Heater.Fire Put Out1987-12-10010 December 1987 PNO-V-87-082:on 871210,fire Occurred in Temporary Tool Storage Trailer in Vicinity of Unit 2 Main Generator Transformers.Caused by 120 Volt Junction Box,Possibly Overloaded from Portable Space Heater.Fire Put Out IR 05000323/19870391987-11-17017 November 1987 Insp Rept 50-323/87-39 on 870805-1030.Violations Noted. Major Areas Inspected:Improperly Authorized Flame Heating of RHR Pipe on 870505 PNO-V-87-074, on 871110,county Inadvertently Actuated Emergency Notification Sys(Sirens).Caused by Wrong Sequence Being Entered Into Sys While Performing Weekly Silent Test. Corrective Action Under Investigation1987-11-10010 November 1987 PNO-V-87-074:on 871110,county Inadvertently Actuated Emergency Notification Sys(Sirens).Caused by Wrong Sequence Being Entered Into Sys While Performing Weekly Silent Test. Corrective Action Under Investigation PNO-V-87-073, on 871107,unit Trip Manually Initiated.Caused by Failure of motor-operated Disconnect in Main Generator 25 Kv Isophase Bus C.Repair & Unit Outage Will Take Between 2 Wks & 2 Months,Depending on Availability of Parts1987-11-0909 November 1987 PNO-V-87-073:on 871107,unit Trip Manually Initiated.Caused by Failure of motor-operated Disconnect in Main Generator 25 Kv Isophase Bus C.Repair & Unit Outage Will Take Between 2 Wks & 2 Months,Depending on Availability of Parts PNO-V-87-066, on 871006,while Performing Periodic Surveillance Testing of Control Rods at 100% Power,Rod Control Urgent Failure Alarm Received on Shutdown Bank A. Caused by Blown Fuses.Fuses Replaced & Alarm Cleared1987-10-0606 October 1987 PNO-V-87-066:on 871006,while Performing Periodic Surveillance Testing of Control Rods at 100% Power,Rod Control Urgent Failure Alarm Received on Shutdown Bank A. Caused by Blown Fuses.Fuses Replaced & Alarm Cleared IR 05000275/19870321987-09-0101 September 1987 Mgt Meeting Repts 50-275/87-32 & 50-323/87-32 on 870817. Major Areas Discussed:Recent Plant Events & Apparent Problem Areas That Have Developed Since Last Mgt Meeting on 870306 PNO-V-87-053, on 870723,high Radiation Alarm Automatically Diverted Liquid Radwaste Flow to Storage Tank.Licensee Determining Root Cause.Chemical Drain Tank Properly Recirculated & Sampled Prior to Discharge Per Procedure1987-07-24024 July 1987 PNO-V-87-053:on 870723,high Radiation Alarm Automatically Diverted Liquid Radwaste Flow to Storage Tank.Licensee Determining Root Cause.Chemical Drain Tank Properly Recirculated & Sampled Prior to Discharge Per Procedure PNO-V-87-051, on 870714,reactor Trip & Safety Injection from 12% Power Occurred.Caused by turbine-generator Trip Due to High Steam Generator Water Level & Flickering High Steam Flow Bistables,Respectively.Root Causes Under Investigation1987-07-14014 July 1987 PNO-V-87-051:on 870714,reactor Trip & Safety Injection from 12% Power Occurred.Caused by turbine-generator Trip Due to High Steam Generator Water Level & Flickering High Steam Flow Bistables,Respectively.Root Causes Under Investigation IR 05000275/19870221987-06-23023 June 1987 Insp Rept 50-275/87-22 on 870520-22.Major Areas Inspected: Followup on Allegation File Number RV-87-A-0094 & Followup on Regional Open Items List ML20215F9001987-06-17017 June 1987 PNS-V-87-005:on 870617,American Protective Svc Notified Util That Security Personnel on Strike Over Monetary Benefits. Licensee Capable to Meet Security Staffing Requirements Through Use of Proprietary Security Personnel PNO-V-87-041, on 870602,engineer in Containment Noted Weepage from RHR Sys Line While RHR in Svc.Cause of Effect Undetermined.Licensee Preparing Work Orders to Isolate, Examine & Repair Weld1987-06-0303 June 1987 PNO-V-87-041:on 870602,engineer in Containment Noted Weepage from RHR Sys Line While RHR in Svc.Cause of Effect Undetermined.Licensee Preparing Work Orders to Isolate, Examine & Repair Weld IR 05000275/19870181987-05-0808 May 1987 Insp Repts 50-275/87-18 & 50-323/87-17 on 870420-24.No Noncompliance or Deviations Noted.Major Areas Inspected: Nonlicensed Staff Training,Followup of Part 21 Repts,Various Vital Areas & Equipment ML20209D5131987-04-23023 April 1987 Updated PNO-V-87-030B:on 870421,onsite Phase of AIT Team Special Insp Into 870410 Loss of Suction to RHR Sys While in half-loop Concluded W/Meeting at Site PNO-V-87-030A, on 870415,Region V Augmented Insp Team Commenced Insp Activities Re 870410 Loss of Suction to RHR While at Half Loop.Team Expects to Stay Onsite Through 870421.Summary of Sequence of Event Encl1987-04-20020 April 1987 PNO-V-87-030A:on 870415,Region V Augmented Insp Team Commenced Insp Activities Re 870410 Loss of Suction to RHR While at Half Loop.Team Expects to Stay Onsite Through 870421.Summary of Sequence of Event Encl PNO-V-87-030, on 870410,RHR Sys Capability Lost for Approx 90 Minutes.Caused by Entrainment of Air within RHR Pumps When RCS Water Level Dropped Due to Water Leakage Through Two Valves.Augmented Insp Team Dispatched1987-04-13013 April 1987 PNO-V-87-030:on 870410,RHR Sys Capability Lost for Approx 90 Minutes.Caused by Entrainment of Air within RHR Pumps When RCS Water Level Dropped Due to Water Leakage Through Two Valves.Augmented Insp Team Dispatched PNO-V-87-028, on 870403,reactor Tripped from 12% Power During Shut Down for First Refueling Outage.Caused by Flicker of High Steam Flow Bistables Coincident w/lo-lo T Average.Investigation Continuing1987-04-0606 April 1987 PNO-V-87-028:on 870403,reactor Tripped from 12% Power During Shut Down for First Refueling Outage.Caused by Flicker of High Steam Flow Bistables Coincident w/lo-lo T Average.Investigation Continuing ML20215G3021987-03-26026 March 1987 Notice of Violation from Insp on 870202-13.App B Re Areas Inspected & Results Encl IR 05000275/19870011987-03-25025 March 1987 Insp Repts 50-275/87-01 & 50-323/87-01 on 870202-13. Violation Noted:Failure to Maintain Control Over Lubricants PNO-V-87-025, on 870321,facility Experienced Safety Injection,Reactor Trip & Unit Trip.Caused by Coincidence of High Steam Flow & Low Steam Generator Pressure Signals Due to Closure of MSIV FCV 41.Piping & Valve Switches Inspected1987-03-23023 March 1987 PNO-V-87-025:on 870321,facility Experienced Safety Injection,Reactor Trip & Unit Trip.Caused by Coincidence of High Steam Flow & Low Steam Generator Pressure Signals Due to Closure of MSIV FCV 41.Piping & Valve Switches Inspected IR 05000275/19860331987-03-17017 March 1987 Insp Repts 50-275/86-33 & 50-323/86-31 on 861215-19. Deficiencies Noted.Major Areas Inspected:Implementation Program for Establishing & Maintaining Environ Qualification of Electrical Equipment Important to Safety IR 05000275/19870091987-03-11011 March 1987 Insp Repts 50-275/87-09 & 50-323/87-08 on 870223-27.No Noncompliance Noted.Major Areas Inspected:Followup of IE Bulletins,Vital Areas & Equipment PNO-V-87-018, on 870301,1-2 Mw/Min Shutdown Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak. Vibration,Induced by Main Generator,Caused Cracking in Welds of Stator Cooling Water Sys Which Occurred on 8702171987-03-0202 March 1987 PNO-V-87-018:on 870301,1-2 Mw/Min Shutdown Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak. Vibration,Induced by Main Generator,Caused Cracking in Welds of Stator Cooling Water Sys Which Occurred on 870217 PNO-V-87-016, on 870221,shutdown Commenced Due to Train B of Solid State Protection Sys Not Returning to Svc within 2 H. Caused by High Steam Generator Level on Generator 1-4 & Feedwater Flow Instabilities & Valve Position Problem1987-02-23023 February 1987 PNO-V-87-016:on 870221,shutdown Commenced Due to Train B of Solid State Protection Sys Not Returning to Svc within 2 H. Caused by High Steam Generator Level on Generator 1-4 & Feedwater Flow Instabilities & Valve Position Problem IR 05000275/19870041987-02-20020 February 1987 Insp Repts 50-275/87-04 & 50-323/87-04 on 861228-870207.No Violations or Deviations Noted.Major Areas Inspected:Plant Operations,Maint & Surveillance Activities & Followup of Onsite Events,Open Items & LERs PNO-V-87-014, on 870217,slow Shutdown from 100% Power Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak.Caused by Cracking in Stator Water Cooling Vent Line Due to Vibration.Outage Expected to Last Approx 1 Wk1987-02-18018 February 1987 PNO-V-87-014:on 870217,slow Shutdown from 100% Power Initiated to Investigate & Repair Main Generator Hydrogen Coolant Leak.Caused by Cracking in Stator Water Cooling Vent Line Due to Vibration.Outage Expected to Last Approx 1 Wk IR 05000275/19870071987-02-12012 February 1987 Insp Repts 50-275/87-07 & 50-323/87-06 on 870202-06. No Items of Noncompliance or Deviations Identified.Major Areas Inspected:Design,Design Changes & Mods & Followup on IE Notices & Nonconformance Repts ML20211M1701987-02-10010 February 1987 Notice of Violation from Insp on 870112-13 IR 05000275/19870061987-02-0606 February 1987 Insp Rept 50-275/87-06 on 870112-13.Violation Noted: Notification of 870102 Emergency Plan Unusual Event Did Not Occur Until 95 Minutes After Declaration IR 05000275/19860321987-01-30030 January 1987 Insp Repts 50-275/86-32 & 50-323/86-30 on 861109-1227 & 870116.No Violations or Deviations Noted.Major Areas Inspected:Plant Operations,Maint & Surveillance Activities, Followup of Onsite Events & Allegations IR 05000275/19870031987-01-30030 January 1987 Insp Repts 50-275/87-03 & 50-323/87-03 on 870112-16.No Violations or Deviations Noted.Major Areas Inspected: Previous Insp Items,Transportation,Solid Waste,Licensee Identified Violation & Facility Tours 1999-09-13 |
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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-V-87-25 Date 03/23/87 h This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information presented is as initially received without verification or evaluation and is basically all that is known by Region V staff on this date.
FACILITY: PACIFIC GAS & ELECTRIC COMPANY Emergency Classification DIABLO CANYON UNIT 2 X Notification of Unusual Event DOCKET NO. 50-323 Alert SAN LUIS OBISP0 COUNTY, CA Site Area Emergency General Emergency Not Applicable
SUBJECT:
REACTOR TRIP AND SAFETY INJECTION On 3/21/87 at 7:43 am (PST), while at 100% power, Unit 2 experienced a safety injection, reactor trip and unit trip. The safety injection signal was caused by the coincidence high steam flow and low steam generator pressure signals. The signals were generated when a Main Steam Isolation valve FCY 41 went shut causing high steam flow and low pressure in the remaining three steam generators. All safety systems operated normally. The licensee terminated the unusual event at 8:04 am in Mode 3. There were no offsite releases as a result of the event. Licensee investigative actions included determining the cause of the isolation valve closure, walkdown inspection of the piping affected by the sudden valve closure, and radiography of the valve itself to verify internal integrity. As of 8:00 am 3/23/87, the licensee's preliminary conclusions are that the valve closure was caused by a short in the valve's closed position limit switch (POS 821). The involved electrical circuitry is such that a short in the valve position limit switch causes the solenoid valve (SV 298) to energize and open, bleeding air from the MSIV air operator, allowing the valve to go shut. Examination of the disassembled position switch shows water intrusion and corrosion in the internals. The valve, its operator and limit switches are located outdoors but the limit switch is gasketed and designed to be weather tight. The piping inspection was completed and showed no damage except for three pipe snubbers which require further testing to verify operability. The radiography of the MSIV showed no damage to valve internals.
The licensee is considering the options of going into the planned refueling outage (scheduled April 6,1987) early or returning to power and delaying the outage. The licensee is considering further investigative actions for other limit switches which might be similarly affected.
There has been regional media interest.
This information is current as of 8:00 am 3/23/87.
CONTACT: M. Mendonca, RV P. Narbut FTS 463-3720 805-595-2354 DISTRIBUTION H St. MNBB Phillips E/W Willste Air Rights Mail:
Chairman Zech ED0 NRR IE NMSS ADM:DMB Comm. Roberts PA OIA RES DOT:Trans Only Conn. Asselstine MPA AE0D Comm. Bernthal 0GC Conin. Carr Regions:
SECV INP0 NSAC ACRS Licensee:
CA (Reactor Licensees) REGION V: FORM 211 PDR Resident Inspector (Revised 3/14/83)
D 8703310520 870323 PDR ISE '](-
Q/
PND-V-87-025 PDR
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