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Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO LER)
MONTHYEARML20154H5291998-10-0808 October 1998 Special Rept:On 980928,meteorological Monitoring Instrumentation Channel Inoperable for Period Greater than 7 Days.Caused by Vendor to Follow Std Industry Practice for Calibr of Instrumentation.Instruments Installed ML20129B8991996-10-17017 October 1996 Special Rept:On 960919-22,DG Failures Experienced.Causes Could Not Be Conclusively Determined Although Kepner Tregoe Problem Analysis Identified Several Possible Causes. Components Identified Possible Contributors Being Monitored ML20065N1171994-04-25025 April 1994 Special Rept:On 940125,unplanned Reactor Trip & ECCS Actuation & Injection Into RCS Occurred.Total Accumulated Actuation Cycles for Four High Head Injection Lines Is Three ML20064N2381994-03-25025 March 1994 Ro:On 940316,determined Recorder 1-SM-X-6706 Inoperable for Indeterminate Period of Time.Caused by Corroded Sensors. Damaged Sensors Replaced & Recorder Returned to Svc on 940317 ML20059D9891994-01-0303 January 1994 Special Rept:On 931201,02,16,18 & 29,diesel Generator Failures Occurred.Causes & Corrective Actions Listed ML20127H3161993-01-15015 January 1993 Special Rept:On 921216,discovered That Prior to Closing EDG Output Breaker,Dg Output Voltage Was Offscale High.Caused by Valid EDG Start Failure.Silicon Controlled Recifier Bank a Placed Into Svc & Bank B Will Be Repaired or Replaced ML20079K9011991-10-31031 October 1991 Suppl to 910925 Special Rept:On 910826,train a Emergency Diesel Generator Tripped During post-maint Testing.Caused by Reversed Wiring Leads in Power Relays.Design Change Issued, Rewiring Performed & Input Leads Corrected ML20085D8251991-10-11011 October 1991 Special Rept:On 910911,EDG 1B Shutdown Due to Excessive Vibration.On 910916,EDG 1B Shutdown Due to Oil Leak on Cylinder 8.On 910919,EDG 1B Shutdown Due to Loud Noises from Air Start Distributor.Distributor Shaft Reinstalled ML20083D5741991-09-25025 September 1991 Special Rept:On 910826,A Train EDG Tripped.Trip Actuated by Reverse Power Relay.Root Cause Analysis Will Be Completed by 911030.Design Change Issued & Implemented to Correct Wiring of Subj Relays & Schematic Drawings ML20083D2951991-09-24024 September 1991 Special Rept:On 910825,Train a Emergency Diesel Generator Tripped on Low Lube Oil Pressure During post-maint Testing. Caused by Large Fluctuations in Engine Revolutions Per Minute.Procedures Re Auxiliary Lube Oil Pump Revised ML20247R5721989-09-25025 September 1989 Ro:On 890902,radiation Monitor Inoperable for Period Exceeding 7 Days.Caused by Installation of Nonfuse Dependent Isolation Devices in Communication Loops of Radiation Data Mgt Sys & Need for Relocation of Monitor Due to New Design ML20245G7151989-04-17017 April 1989 Ro:On 890316,train a Emergency Diesel Generator Tripped on Low Oil Pressure During Initial Startup.Caused by Engine Lube Oil Monitoring Circuit Becoming Active Before Engine Speed Developed Sufficient Lube Oil Pressure ML20154F3231988-09-0909 September 1988 Special Rept:On 880811,fuel Oil Leak Required Engine Shutdown & on 880812,Train B Emergency Diesel Generator Tripped.Caused by Incorrect Setting of Water Jacket Temp Controller.Adjustment Knob Protected from Misadjustment ML20207C3181988-07-22022 July 1988 Special Rept:On 880224,low Lube Oil Pressure Trip Occurred. Caused by 8-wk Maint Outage Resulting in Slower than Normal Engine Acceleration During Engine Start.Development of Design Change to Relocate Coolant Pressure Switch Underway ML20238E4601986-08-28028 August 1986 Partially Withheld Secrity Event Rept:On 860824,bomb Threat Received for Plants.Bomb Search Initiated.No Suspicious Objects Found 1998-10-08
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217H2841999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Seabrook Station. with ML20212D1461999-09-17017 September 1999 SER Accepting Request to Use Proposed Alternative to Certain Weld Repair Requirements in ASME Boiling & Pressure Vessel Code ML20216F5141999-08-31031 August 1999 Rept on Status of Public Petitions Under 10CFR2.206 ML20212B8671999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Seabrook Station. with ML20210Q7581999-08-11011 August 1999 SER Approving Proposed Merger of CES & Bec,Which Will Create New Parent Company of Canal ML20210R9781999-08-0606 August 1999 ISI Exam Rept of Seabrook Station, for RFO 6,period 3 ML20210J8681999-08-0303 August 1999 SER Approving License Transfer from Montaup Electric Co to Little Bay Power Corp & Approval of Conforming Amend for Seabrook Station Unit 1 ML20210R6001999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Seabrook Station, Unit 1.With ML20210H1151999-06-30030 June 1999 Naesc Semi-Annual Fitness-for-Duty Rept for 990101-0630 ML20209H1371999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Seabrook Station, Unit 1.With ML20195G5391999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Seabrook Station, Unit 1.With ML20195C0491999-05-25025 May 1999 Offshore Intake Seal Deterrent Barrier Design ML20206E4761999-04-30030 April 1999 LER 99-S01-00:on 990408,contractor Employee Was Granted Temporary Unescorted Access to Seabrook Station Protected Area.Caused by Failure of Contractor Employee to Provide Accurate Info.Individual Access Revoked.With ML20206N1751999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Seabrook Station, Unit 1.With ML20196L2081999-04-19019 April 1999 Rev 01-07-00 to RE-21, Cycle 7 Colr ML20205K5441999-03-31031 March 1999 Decommissioning Update ML20205L8141999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Seabrook Station. with ML20205C1981999-03-24024 March 1999 Safety Evaluation Concluding That Proposed Relief Request IR-8,Rev 1,provides Acceptable Alternative to ASME Code Requirements.Recommends Authorization of Proposed Alternative Pursuant to 10CFR50.55a(a)(3)(i) ML20207F4941999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for Seabrook Station. with ML20199E6731998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for Seabrook Station, Unit 1.With ML20198P1831998-12-31031 December 1998 LER 98-S01-00:on 981214,incomplete pre-employment Screening Records Was Noted.Caused by Failure of Contractor Employee to Provide Accurate Info.Subject Contractor Employees Employment Was Terminated.With ML20202E8241998-12-31031 December 1998 Naesc Semi-Annual Fitness-for-Duty Rept for 980701-981231 ML20196F5741998-12-0202 December 1998 Safety Evaluation Concluding That Licensee Has Established Acceptable Program to Verify Periodically design-basis Capability of safety-related MOVs at Seabrook ML20198B8661998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for Seabrook Station, Unit 1.With ML20195D0311998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for Seabrook Station, Unit 1.With ML20154H5291998-10-0808 October 1998 Special Rept:On 980928,meteorological Monitoring Instrumentation Channel Inoperable for Period Greater than 7 Days.Caused by Vendor to Follow Std Industry Practice for Calibr of Instrumentation.Instruments Installed ML20154M8421998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for Seabrook Generating Station,Unit 1.With ML20151V5951998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for Seabrook Station, Unit 1.With ML20237B4501998-07-31031 July 1998 Monthly Operating Rept for July 1998 for Seabrook Station ML20236R1781998-06-30030 June 1998 Naesc Semi-Annual Fitness-for-Duty Rept for 980101-0630 ML20236M3591998-06-30030 June 1998 Monthly Operating Rept for June 1998 for Seabrook Station, Unit 1 ML20237A4871998-06-0303 June 1998 North Atlantic Seabrook Station 1998 Exercise on 980603 ML20248M2951998-05-31031 May 1998 Monthly Operating Rept for May 1998 for Seabrook Station, Unit 1 ML20247G2641998-04-30030 April 1998 Monthly Operating Rept for Apr 1998 for Seabrook Station ML20247H3171998-04-27027 April 1998 Rev 1 to Seabrook Station SGs B & C Isi,May/June 1997 ML20216F8891998-03-31031 March 1998 Monthly Operating Rept for Mar 1998 for Seabrook Station 05000443/LER-1998-002, Re Potential Safety Injection Pump Runout Conditions Identified on 980113.LER 98-002-00 Retracted1998-03-20020 March 1998 Re Potential Safety Injection Pump Runout Conditions Identified on 980113.LER 98-002-00 Retracted ML20216H9211998-03-13013 March 1998 Fitness for Duty Program Performance Data Personnel Subject to 10CFR26 ML20248L2811998-02-28028 February 1998 Monthly Operating Rept for Feb 1998 for Seabrook Station, Unit 1 ML20197A7531998-02-27027 February 1998 Safety Evaluation Accepting License Request for Relief from ASME Code,Section IX Requirements Re Inservice Insp of RHR Heat Exchanger Nozzle Welds & Reactor Vessel Closure Head Nuts ML20202G3701998-01-31031 January 1998 Monthly Operating Rept for Jan 1998 for Seabrook Station ML20198G0271997-12-31031 December 1997 Commonwealth Energy Sys 1997 Annual Rept ML20248L7711997-12-31031 December 1997 Western Massachusetts Electric 1997 Annual Rept. Supporting Info,Encl ML20198G1021997-12-31031 December 1997 Baycorp Holdings 1997 Annual Rept ML20198N7021997-12-31031 December 1997 Monthly Operating Rept for Dec 1997 for Seabrook Station, Unit 1 ML20198G0351997-12-31031 December 1997 Eastern Edison Co 1997 Annual Rept ML20198G0681997-12-31031 December 1997 Taunton Municipal Lighting Plant 1997 Annual Rept ML20248L7671997-12-31031 December 1997 North Atlantic 1997 Annual Rept ML20198F9511997-12-31031 December 1997 United Illuminating Co 1997 Annual Rept ML20236M9561997-12-31031 December 1997 Amended Public Service of New Hampshire 1997 Annual Rept 1999-09-30
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New Hampshire Ted C. Feigenbaum Yhh h Preddent and Chief Enecutive OHicer NYN-91165 October 11, 1991 United States Nuclear Regulatory Commission Washington, D.C. 20555 .
Attention: Document Control Dcsk
References:
(a) Facility Operating Lict.tse No. NPF-86, Docket No.53-443 (b) Seabrook Station Technical Specification 4.8.1.1.3
Subject:
Diesel Generator Special Report Gentlemen:
The following Diesel Generator Special Report documents six failures of Emergency Diesel Generator 1B (EDG 1B), which occurred at Scabrook Station during the period Septemiser 11-25, 1991. This report is provided pursuant to Technical Specification Surveillance Requirement 4.8.1.1.3 and Technical Specification 6.8.2. Two of these failures were determined to be valid test fa;. lures and the four rcmaining failures were determined to be non-valid test failures. The test failures were determined as valid or non-valid in accordance with the criteria of Regulatory Guide 1.108 ' Periodic Testing of Diesel Generator Units Used as Onsite Electric Power Systems at Nueh.ar Power Plants." At the time of these events, the plant was shutdown for refueling (in Mode 5) with the A train emergency diesel generator operabic.
Event # 1 - September 11.1991 at 1745 linart During the performance of 'he monthly operability surveillance, EDG 1B was shutdown after 213 minutes of run time due to escessive vibration and overheating in the air start left bank air start distributor manifold arca, it was discovered that the air start distributor lines to cylinders #3, #4, #6 and #7 had failed. The air start distributor was subscauently disassembled. Upon disassembly, it was discovered that there was evidence of rubbing between the rotor and housing mating surfaces. The acceptance eriteria of the surveillance test was met but this test was determined to be a valid failure due to the required vibration shutdown. This was the first valid failure of EDG 1B in the last 20 and last 100 valid tests.
1 Eve nt -# 2 - September 16.1991 at 0059 Hours During the performance of the 18-Month Operability and Engineered Safeguards Purr. . l and Valve Response Time Testing Surveillance, EDG 1B was intentionally shutdown after 28 ,
minutes of run time due to an oil leak on #8 cylinder. After the oil leak was repa: red, it j was determined that the oil leak was not of the magnitude that would have resulted in diesel '
generator damage or failure. As a result, it was determined that this was a non-va!id test j failure, l 9110170197 911011 PDR ADOCK 05000443 S PDR / L i
!j()
New Hampshire Yankee Division of Public Service Compon'y of New Hampshire z l
P.O. Box 300
- Telephone (603) 474 9521 1
. . , _ . - _ - _ .. -._ . _=_.- --- - -m .--
- United States Nuclear Regulatory Comtnission October M1,1991 Attention: Document Control Desk Page two Ey. cat # 31 Sententpfr 16.1901 at 0721 Ilours During the performance of the 18 Month Operability and Engineered Safeguatds Pump and Valve Response Time Testinr Surveillance, EDG 1B was shutdown after $6 minutes of run time. The diesel generator was shutdown due to the severing of two air lines on the left bank air start manifold. Upon engine shutdown, an investigation identified broken air start -distributot lines to cylinders #4, # 5, # 6 and # 7. The air bank distributor was disassembled and additional ciidence of rubbing between the rotor and housing mating surfaces was observed. Additional engine disassembly was performed to deter.nine the cause of the air start distributor inuuced failures. As a result of the shutdown of EDO -1B due to abnormal conditions that would.have resulted in er;uipment damage, it was determined that this was a valid test failure. This we.s the second valid failure of EDG IB in the last 20 and last 100 valid tests.
Event #4 ~- Scotember 10.1001 nt 055? Ilours .
During the performance of a maintenance engine run for troubleshootir.g and d u collection, EDO 1B was shutdown after 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> and 47 minutes of run time due to loud -
ncises from the air start distributor. Since this engine run was performed in the process of troubleshooting, it was determined that this was a non-valid test failure.
Event #5 - Scotember 21.1991 at 2113 If oug During'the_ performance of a maintenance engine rnn for troubleshooting and data collection, EDG 111 was shutdown after 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> and 8 minutes of run time due to 1(,ad noises from the air start distributor. Since this enginc run was performed in the process of troubleshooting, it was determined that this was a non-valld- test failure.
Event #6 - September 25.1901 at 0327 Hours During-the performance of a maintenance engine run for troubleshooting and data collection EDG IB failed to start. Starting circuit monitoring equipment, that had bec :
, _ temporarily installed for troubleshooting purposes, shorted to ground. The short to ground L
_ simulated a- failed potential -transforn.cr fuse and caused an automatie engine shutdown.
This was, the first start attempt after rebuilding the air start distributor following the failure reported in Event #5. Since this temporary mon:toring equipment is not part of the defined diesel generator unit desige and because this engine run was for troubleshooting and data collection, it = was determined that this was a non-valid test failure, t-Root Cause A number of possible root causes were identified and evaluated The most probable cause D of the test -failures was determined to be excessive vibration of -the left bank air start
- distributor. The vibration caused rubbing between the rotor and air distributor housing.
This rubbing eventually resulted in~ noisy operation and overheating of- the left air start distributor (Event #4 and #5), the severing of the left air start distrib.w air lines (Event
- 1 and #3) and leaking oil line (Event #2).
The ro_ot cause of Evect -#6 was determined to be the use of faulty test equipment which caused an unexpected short to ground. This electrical short circuiting simulated a failed potential transformer fuse causing the engine to automatically shutdown.
L i
4 United States Nuclear Regulatory Commission October 11., 1991 Attenilon: Document Control Desk Pye three Corrective Action The original air start distributo: shaft was reinstalled and the rotor aswmbly was replaced.
The severed air lines and oi! leaks were repaired. EDG IB is cu:4cntly operable and is curtently being tested on a weekly basis pursuant to Tt.chnical 5pecification Surveillance Requiremont 4.8.1.1.2.a. This test frequency will be maintained until seven consecutive failure-free demands have been perfornied and the number af failures in the last 20 valid d:mrnds has been reduced to one or less. Additianally, to enhance EDG performance, actions are be'ng taken to reduce the total Emergency Diesel Generator vibrations.
Shciuld you have ai.y questions regarding this report, please contact Mr. James M.
Peschel, Regulatory Ct 1.pliance Manager, at (603) 474-9521 extension 3772. _
Very truly 6 Irs, e
(,)/s,g #.A y Tad C. Feighan- /
TCF:JWC/jwc tc: Mr. Thomas T. Martin Regional Administrator United States Nuclear Rep latory Commission Region 1 475 Allendale Road King of Prussia, PA 19496 Mr. Gordon E. Edisua, Senior Project Manager Pioject Directorate 1 Division of Reactor Projects United States Nuclea- Regulatory Commission Washington, DC 20555 Mr. Ncel Dudley NRC Senior Resident Inspector P. O. Box 1149 Seabrook, Nil 03874 s