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| {{#Wiki_filter:NRCForm366U.S.NUCLEARREGULATORY COMMISSION (6-1996)LICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/characters foreachblock)APPROVEOBY0MBNO.3(504)104 EXPIRES05/30/2001 ESTPAATED SVRDENPERRESPONSETOCOMPLYWITHTI43MANDATORY eIFORMATION COLLECTION REOVEST:500HRS.REPORTEDLESSONSLEARNEDAREerCORPORATED trfoTHELICENSINO PROCESSANOFEDSACKTOINDVSTRYFORWARDCOIVFAENTS REOARDINO SVRDENESTSJATETOTHEeIFORMATKNI ANORECORDSMANAGEMENT SRANCHIT%FaaxV.SNVCLEARREOIAATORY COLSJISSIOH. | | {{#Wiki_filter:NRC Form 366 U.S.NUCLEAR REGULATORY COMMISSION (6-1996)LICENSEE EVENT REPORT (LER)(See reverse for required number of digits/characters for each block)APPROVEO BY 0MB NO.3(504)104 EXPIRES 05/30/2001 ESTPAATED SVRDEN PER RESPONSE TO COMPLY WITH TI43 MANDATORY eIFORMATION COLLECTION REOVEST: 50 0 HRS.REPORTED LESSONS LEARNED ARE erCORPORATED trfo THE LICENSINO PROCESS ANO FED SACK TO INDVSTRY FORWARD COIVFAENTS REOARDINO SVRDEN ESTSJATE TO THE eIFORMATKNI ANO RECORDS MANAGEMENT SRANCH IT%Faax V.S NVCLEAR REOIAATORY COLSJISSIOH. |
| WASHNOTON. | | WASHNOTON. |
| OC20555000I, ANOTOTHEPAPERWORK REDVCTION PROJECT(3I500IDII OFFCEOFScrNAOEMENT ANDSVOOETWASHrNOTONi DC20500FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 PAOE(3)1of4TITLE(4)Victoreen Containment HighRangeRadiation MonitorsNotEnvironmentally Qualified toWithstand Post-LOCA Conditions EVENTDATE(5)LERNUMBER(6)REPORTDATE(7)OTHERFACILITIES INVOLVED(8)MONTHDAY0716YEAR1999YEARSEQUENTIAL NUMBER1999-019REVISIONNUMBER00MONTH08DAY16YEAR1999FACILITYNAMED.C.Cook-Unit2FACILITYNAMEDOCKETNUMBER05000-316 DOCKETNUMBEROPERATING MODE(9)THISREPORTISSUBMITTED PURSUANTTOTHEREQUIREMENTS OF10CFRIi:(Checkoneormor20.2201(b)20.2203(a)(2)(v) 50.73(a)(2)(i) e)(11)50.73(a)(2)(viii)
| | OC 20555000I, ANO TO THE PAPERWORK REDVCTION PROJECT (3I500IDII OFFCE OF ScrNAOEMENT AND SVOOET WASHrNOTONi DC 20500 FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKETNUMBER(2) 05000-315 PAOE (3)1 of4 TITLE (4)Victoreen Containment High Range Radiation Monitors Not Environmentally Qualified to Withstand Post-LOCA Conditions EVENT DATE (5)LER NUMBER (6)REPORT DATE (7)OTHER FACILITIES INVOLVED (8)MONTH DAY 07 16 YEAR 1999 YEAR SEQUENTIAL NUMBER 1999-019 REVISION NUMBER 00 MONTH 08 DAY 16 YEAR 1999 FACILITY NAME D.C.Cook-Unit 2 FACILITY NAME DOCKET NUMBER 05000-316 DOCKET NUMBER OPERATING MODE (9)THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR Ii: (Check one or mor 20.2201 (b)20.2203(a)(2)(v) 50.73(a)(2)(i) e)(11)50.73(a)(2)(viii) |
| POWERLEVEL(10)020.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1) 50.36(c)(2)
| | POWER LEVEL (10)0 20.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1) 50.36(c)(2) |
| LICENSEECONTACTFORTHISLER(12)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50,73(a)(2)(x) 73.71OTHERSpeo/YinAbstractbetorvornNRCForm3SSA NAMEMs.BrendaW.O'ourke,Compliance EngineerTELEPHONE NUMBER0ndrrdeAreaCode)(616)465-5901x2604COMPLETEONELINEFOREACHCOMPONENT FAILUREDESCRIBED INTHISREPORT13CAUSESYSTEMCOMPONNTMAIJUFACTUR RREPORTABLE TOEPIXCAUSESYSTEMCOMPONENT MANUFACTURER REPORTABLE TOEPIXSUPPLEMENTAL REPORTEXPECTED14YESIIYescomleteEXPECTEDSUBMISSION DATEXEXPECTEDSUBMISSION DATE15MONTHDAYYEARAbstract(Limitto1400spaces,I.e.~approximately 15single-spaced typewritten lines)(16)OnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thatthecontainment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails,"
| | LICENSEE CONTACT FOR THIS LER (12)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50,73(a)(2)(x) 73.71 OTHER Speo/Y in Abstract betorv or nNRCForm3SSA NAME Ms.Brenda W.O'ourke, Compliance Engineer TELEPHONE NUMBER 0ndrrde Area Code)(616)465-5901 x2604 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13 CAUSE SYSTEM COMPON NT MAIJUFACTUR R REPORTABLE TO EPIX CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO EPIX SUPPLEMENTAL REPORT EXPECTED 14 YES IIYes com lete EXPECTED SUBMISSION DATE X EXPECTED SUBMISSION DATE 15 MONTH DAY YEAR Abstract (Limit to 1400 spaces, I.e.~approximately 15 single-spaced typewritten lines)(16)On May 21, 1999, during an Environmental Qualification (EQ)program self-assessment, preliminary review identified that the containment high range radiation monitors (HRRM)may not be environmentally qualified to withstand the effects of a Loss of Coolant Accident (LOCA).The self-assessment found that D.C.Cook's evaluation of NRC Information Notice (IN)97-45,"Environmental Qualification Deficiency for Cables and Containment Penetration Pigtails," failed to adequately address the susceptibility of the containment HRRMs to moisture intrusion. |
| failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.
| | IN'97-45 identified that electrical signal cables and connectors found in HRRMs are sensitive to moisture exposure effects, such as from a LOCA or pipe break event.Industry events have identified that moisture intrusion into the cable jacket and connectors has resulted in erratic indication of radiation levels and loss of HRRM function.Based on continued evaluation of the EQ deficiencies, the Unit 1 and 2 HRRMs were declared inoperable on July 16, 1999.The apparent cause was inadequate design control.In response to NRC IN 89-63, a design change to the HRRM system added drainage features to several components. |
| IN'97-45identified thatelectrical signalcablesandconnectors foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors hasresultedinerraticindication ofradiation levelsandlossofHRRMfunction. | | However, the EQ requirement that the HRRM system be leaktight against possible moisture intrusion was not considered. |
| Basedoncontinued evaluation oftheEQdeficiencies, theUnit1and2HRRMsweredeclaredinoperable onJuly16,1999.Theapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.
| | A permanent solution for the susceptibility of the HRRMs to moisture intrusion will be developed to support HRRM operability in Modes 1-4.Options for the permanent solution are currently under review and the method selected will be implemented prior to Mode 4 for each unit.An evaluation of the as-built configuration for other low signal current application EQ equipment is also being performed to identify other electrical equipment that may be susceptible to moisture intrusion due to a LOCA and/or pipe break condition. |
| However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered. | | This evaluation will be completed by September 30, 1999.This condition has minimal safety significance due to the availability of alternate post-accident radiation monitoring instrumentation. |
| Apermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandthemethodselectedwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isalsobeingperformed toidentifyotherelectrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAand/orpipebreakcondition.
| | '3)'T)08240285 3)'T)08'PDR ADOCK 050003i 5 S PDR |
| Thisevaluation willbecompleted bySeptember 30,1999.Thiscondition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.
| |
| '3)'T)08240285 3)'T)08'PDRADOCK050003i5SPDR | |
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| NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEARLERNUMBER(6)SEQUENTIAL NUMBERREVISIONNUMBERPAGE(3)2of4TEXT(lfmorespaceisrequired, useadCh'tional copiesofNRCForm(366A)(17)Conditions PriortoEventUnit1wasinMode5,ColdShutdownUnit2wasinMode5,ColdShutdown1999-01900DescritionofEventOnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thattheRadiation Monitoring System's(RMS)[EIIS:IL]
| | NRC FORM 366A U.s.NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKET NUMBER(2)05000-315 YEAR LER NUMBER (6)SEQUENTIAL NUMBER REVISION NUMBER PAGE (3)2of4 TEXT (lf more space is required, use adCh'tional copies of NRC Form (366A)(17)Conditions Prior to Event Unit 1 was in Mode 5, Cold Shutdown Unit 2 was in Mode 5, Cold Shutdown 1999-019 00 Descri tion of Event On May 21, 1999, during an Environmental Qualification (EQ)program self-assessment, preliminary review identified that the Radiation Monitoring System's (RMS)[EIIS:IL]Victoreen containment high range radiation monitors (HRRM)may not be environmentally qualified to withstand the effects of a Loss of Coolant Accident (LOCA).The self-assessment found that D.C.Cook's evaluation of NRC Information Notice (IN)97-45,"Environmental Qualification Deficiency for Cables and Containment Penetration Pigtails," failed to adequately address the susceptibility of the containment HRRMs to moisture intrusion. |
| Victoreen containment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails," | | IN 97-45 identified that electrical signal cables[EIIS:CBL1] |
| failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.
| | and connectors |
| IN97-45identified thatelectrical signalcables[EIIS:CBL1]
| |
| andconnectors
| |
| [EIIS:CON] | | [EIIS:CON] |
| foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors canresultinerraticindication ofradiation levelsincontainment.
| | found in HRRMs are sensitive to moisture exposure effects, such as from a LOCA or pipe break event.Industry events have identified that moisture intrusion into the cable jacket and connectors can result in erratic indication of radiation levels in containment. |
| Inaddition, Supplement 1toIN97-45identified thatHRRMshaveexperienced significant positiveandnegativecurrentflowasaresultofinducedcurrentsinRockbestos coaxialsignalcableswhenexposedtohightemperature transient conditions.
| | In addition, Supplement 1 to IN 97-45 identified that HRRMs have experienced significant positive and negative current flow as a result of induced currents in Rockbestos coaxial signal cables when exposed to high temperature transient conditions. |
| Asaresult,thedetection functionoftheHRRMswouldbeimpacted.
| | As a result, the detection function of the HRRMs would be impacted.Recent evaluation of the HRRM EQ deficiencies identified that in response to NRC IN 89-63,"Possible Submergence of Electrical Circuits Located Above the Flood Level Because of Water Intrusion and Lack of Drainage," D.C.Cook added drainage features (e.g., weep holes and slits in sealtite flex conduit)to the HRRM electrical enclosures (conduit and junction boxes[EIIS:JBX]) |
| Recentevaluation oftheHRRMEQdeficiencies identified thatinresponsetoNRCIN89-63,"Possible Submergence ofElectrical CircuitsLocatedAbovetheFloodLevelBecauseofWaterIntrusion andLackofDrainage,"
| | in containment. |
| D.C.Cookaddeddrainagefeatures(e.g.,weepholesandslitsinsealtiteflexconduit)totheHRRMelectrical enclosures (conduitandjunctionboxes[EIIS:JBX]) | | However, this resulted in a non-leaktight HRRM configuration, potentially exposing the moisture sensitive components to LOCA conditions. |
| incontainment.
| | Based on above information, it was concluded that the Unit 1 and 2 HRRMs would not be capable of performing their intended design function.As a result, on July16, 1999, the HRRMs were declared inoperable at 1558 hours.Cause of Event The apparent cause was inadequate design control.In response to NRC IN 89-63, a design change to the HRRM system added drainage features to several components. |
| However,thisresultedinanon-leaktight HRRMconfiguration, potentially exposingthemoisturesensitive components toLOCAconditions. | | However, the EQ requirement that the HRRM system be leaktight against possible moisture intrusion was not considered. |
| Basedonaboveinformation, itwasconcluded thattheUnit1and2HRRMswouldnotbecapableofperforming theirintendeddesignfunction.
| | Subsequent opportunities to identify this condition were missed during D.C.Cook's evaluation of IN 97-45 and its supplement. |
| Asaresult,onJuly16,1999,theHRRMsweredeclaredinoperable at1558hours.CauseofEventTheapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.
| | The concerns identified in the Information Notice were determined not to be applicable to D.C.Cook because the HRRMs use Brand Rex signal cabling versus Rockbestos cabling as described in IN 97-45.Anal sis of Event This LER is being submitted in accordance with the requirements of 10CFR50.73(a)(2)(i)(B) for a condition prohibited by plant Technical Specifications. |
| However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered. | | TS 3.3.3.1 requires the containment HRRMs to be operable in Modes 1-4.UFSAR Section 11.3, states that the Radiation Monitoring System is designed to perform two basic functions: |
| Subsequent opportunities toidentifythiscondition weremissedduringD.C.Cook'sevaluation ofIN97-45anditssupplement. | | 1)warn of any radiation hazards which might develop, and 2)give early warning which might lead to a radiation hazard or plant damage.The RMS instruments are located at selected points in and around the plant to detect, compute, and record radiation levels.The components of the RMS are designed to operate during all expected environmental conditions for normal operation, and specific components are designed to operate during adverse or accident conditions. |
| Theconcernsidentified intheInformation Noticeweredetermined nottobeapplicable toD.C.CookbecausetheHRRMsuseBrandRexsignalcablingversusRockbestos cablingasdescribed inIN97-45.AnalsisofEventThisLERisbeingsubmitted inaccordance withtherequirements of10CFR50.73(a)(2)(i)(B) foracondition prohibited byplantTechnical Specifications.
| | The subject radiation monitors include the Victoreen containment high range radiation monitors (1-VRA-1310/1410 and 2-VRA-2310/2410) which provide indication of containment radiation levels during post-LOCA conditions and are utilized in assessing possible core damage.NRC FORM 366A (6-1998) |
| TS3.3.3.1requiresthecontainment HRRMstobeoperableinModes1-4.UFSARSection11.3,statesthattheRadiation Monitoring Systemisdesignedtoperformtwobasicfunctions:
| | NRC FORM 366A U.s.NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 OOCKET NUMBER(2)05000-315 YEAR 1999 LER NUMBER (6)SEQUENTIAL NUMBER 019 REVISION NUMBER 00 PAGE (3)3of4 TEXT (if more space is required, use addi(tonal copies of NRC Form (366A)(17)A typical HRRM consists of a detector, associated Brand Rex triaxial cabling, conduit, junction boxes and Amphenol connectors. |
| 1)warnofanyradiation hazardswhichmightdevelop,and2)giveearlywarningwhichmightleadtoaradiation hazardorplantdamage.TheRMSinstruments arelocatedatselectedpointsinandaroundtheplanttodetect,compute,andrecordradiation levels.Thecomponents oftheRMSaredesignedtooperateduringallexpectedenvironmental conditions fornormaloperation, andspecificcomponents aredesignedtooperateduringadverseoraccidentconditions. | | Amphenol connectors are located at the penetration pigtails and other electrical cable connections, and at a junction box located at the top of the containment penetration flood-up tubes.Each Amphenol connector is enclosed in a Raychem boot seal, with the associated detector cabling contained within a conduit system.The junction box and conduit system contain weep holes which were added in response to NRC IN 89-63.EQ testing performed by Victoreen in 1978 experienced numerous failures in attempting to qualify a connector assembly for in-containment LOCA use.The only documented successful simulated LOCA testing was for cable and connectors that were enclosed in leaktight conduits.This configuration prevents moisture intrusion into the cable and connectors during post-LOCA conditions. |
| Thesubjectradiation monitorsincludetheVictoreen containment highrangeradiation monitors(1-VRA-1310/1410 and2-VRA-2310/2410) whichprovideindication ofcontainment radiation levelsduringpost-LOCA conditions andareutilizedinassessing possiblecoredamage.NRCFORM366A(6-1998)
| | NRC IN 97-45, identified potential EQ deficiencies associated with Rockbestos coaxial cables and Amphenol connectors used in containment HRRM systems.Subsequent vendor EQ testing concluded that moisture could permeate the HRRM coaxial cable jacket during p LOCA and cause partial shorting of the monitor signal at the connectors. |
| NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1OOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)3of4TEXT(ifmorespaceisrequired, useaddi(tonal copiesofNRCForm(366A)(17)AtypicalHRRMconsistsofadetector, associated BrandRextriaxialcabling,conduit,junctionboxesandAmphenolconnectors.
| | Because of the small signal current output from the HRRMs (nominally pico-amperes), partial shorting of the signal could result in loss of HRRM function.In addition, Supplement 1 identified that HRRMs cabling is susceptible to thermally-induced currents as a result of extreme temperature transients. |
| Amphenolconnectors arelocatedatthepenetration pigtailsandotherelectrical cableconnections, andatajunctionboxlocatedatthetopofthecontainment penetration flood-uptubes.EachAmphenolconnector isenclosedinaRaychembootseal,withtheassociated detectorcablingcontained withinaconduitsystem.ThejunctionboxandconduitsystemcontainweepholeswhichwereaddedinresponsetoNRCIN89-63.EQtestingperformed byVictoreen in1978experienced numerousfailuresinattempting toqualifyaconnector assemblyforin-containment LOCAuse.Theonlydocumented successful simulated LOCAtestingwasforcableandconnectors thatwereenclosedinleaktight conduits.
| | Thermally-induced currents have been found to impact the accuracy of the HRRMs.E In 1990, drainage features were added to D.C.Cook's HRRM system in response to NRC IN 89-63.Industry concerns were identified regarding the lack of drainage holes in containment electrical enclosures that may become submerged during a LOCA event.Without the appropriate drainage, water could collect inside the enclosures and cause shorting of the electrical components contained in the enclosures. |
| Thisconfiguration preventsmoistureintrusion intothecableandconnectors duringpost-LOCA conditions.
| | Although D.C.Cook's HRRM conduit system contains weep holes, the moisture intrusion potential of the subject connectors is much more limited than that described in the Victoreen test reports and NRC IN 97-45.In these tests, the coaxial cable and sealed connectors were directly exposed to steam and spray conditions, whereas D.C.Cook's cable and sealed connectors are contained within a conduit system.Because of the additional protection given by the conduit system, the maximum amount of moisture that could potentially come in contact with the connectors is limited by the internal free air space of the conduit.During the increasing containment pressure portion of a LOCA transient, the steam would fill the conduit, displacing the air inside the conduit and result in the trapped steam condensing on the colder cable and conduit internal walls.This amount of moisture intrusion is much more limited than would occur in an open system (i.e., with no conduit enclosure). |
| NRCIN97-45,identified potential EQdeficiencies associated withRockbestos coaxialcablesandAmphenolconnectors usedincontainment HRRMsystems.Subsequent vendorEQtestingconcluded thatmoisturecouldpermeatetheHRRMcoaxialcablejacketduringpLOCAandcausepartialshortingofthemonitorsignalattheconnectors.
| | The design function of the containment HRRMs is to provide operators with post-LOCA indication of containment radiation levels which are also utilized in assessing possible core damage.Although the identified EQ deficiencies could render the HRRMs inoperable following a LOCA, alternative means of performing this monitoring function exist through other post-accident monitoring instrumentation. |
| BecauseofthesmallsignalcurrentoutputfromtheHRRMs(nominally pico-amperes),
| | This includes the post-accident monitoring system and the post-accident grab sample pallet in accordance with plant emergency procedures. |
| partialshortingofthesignalcouldresultinlossofHRRMfunction.
| | Based on the above information, the identified condition has minimal safety significance due to the availability of alternate post-accident radiation monitoring instrumentation. |
| Inaddition, Supplement 1identified thatHRRMscablingissusceptible tothermally-inducedcurrentsasaresultofextremetemperature transients.
| | Corrective Actions A permanent solution for the susceptibility of the HRRMs to moisture intrusion will be developed to support HRRM operability in Modes 1-4.Options for the permanent solution are currently under review and will be implemented prior to Mode 4 for each unit.An evaluation of the as-built configuration for other low signal current application EQ equipment is being performed to identify other additional electrical equipment that may be susceptible to moisture intrusion due to a LOCA or pipe break condition. |
| Thermally-induced currentshavebeenfoundtoimpacttheaccuracyoftheHRRMs.EIn1990,drainagefeatureswereaddedtoD.C.Cook'sHRRMsysteminresponsetoNRCIN89-63.Industryconcernswereidentified regarding thelackofdrainageholesincontainment electrical enclosures thatmaybecomesubmerged duringaLOCAevent.Withouttheappropriate | | The evaluation will include a review of the current EQ Program documentation regarding requirements for NRC FORM 366A (6-1998) |
| : drainage, watercouldcollectinsidetheenclosures andcauseshortingoftheelectrical components contained intheenclosures.
| | NRC FORM 366A U.S.NUCLEAR REGULATORY COMMISSION (6-1 998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKET NUMBER(2)05000-315 YEAR 1999 LER NUMBER (6)SEQUENTIAL NUMBER 019 REVISION NUMBER 00 PAGE (3)4 of 4 TEXT (lf more space is required, use additional copies of NRC Eorm (366A)(17)leaktight electrical enclosures. |
| AlthoughD.C.Cook'sHRRMconduitsystemcontainsweepholes,themoistureintrusion potential ofthesubjectconnectors ismuchmorelimitedthanthatdescribed intheVictoreen testreportsandNRCIN97-45.Inthesetests,thecoaxialcableandsealedconnectors weredirectlyexposedtosteamandsprayconditions, whereasD.C.Cook'scableandsealedconnectors arecontained withinaconduitsystem.Becauseoftheadditional protection givenbytheconduitsystem,themaximumamountofmoisturethatcouldpotentially comeincontactwiththeconnectors islimitedbytheinternalfreeairspaceoftheconduit.Duringtheincreasing containment pressureportionofaLOCAtransient, thesteamwouldfilltheconduit,displacing theairinsidetheconduitandresultinthetrappedsteamcondensing onthecoldercableandconduitinternalwalls.Thisamountofmoistureintrusion ismuchmorelimitedthanwouldoccurinanopensystem(i.e.,withnoconduitenclosure).
| | This evaluation will be completed by September 30, 1999.Based on results of the evaluation, appropriate corrective actions will be taken to address any identified EQ discrepancies. |
| Thedesignfunctionofthecontainment HRRMsistoprovideoperators withpost-LOCA indication ofcontainment radiation levelswhicharealsoutilizedinassessing possiblecoredamage.Althoughtheidentified EQdeficiencies couldrendertheHRRMsinoperable following aLOCA,alternative meansofperforming thismonitoring functionexistthroughotherpost-accidentmonitoring instrumentation.
| | AEP:NRC:1260GH,"Enforcement Actions 98-150, 98-151, 98-1 52 and 98-186 Reply to Notice Of Violation October 13, 1998", dated March 19, 1999, responded to identified programmatic weaknesses in the plant Design and Licensing Basis and the Training and Qualification of personnel. |
| Thisincludesthepost-accident monitoring systemandthepost-accident grabsamplepalletinaccordance withplantemergency procedures.
| | The Engineering Leadership Plan establishes a configuration management program to control plant design and a new design control process, which includes design verification, design document control, vendor technical documentation control and testing of design changes.As part of the Restart effort, an improved operating experience program is being developed. |
| Basedontheaboveinformation, theidentified condition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.
| | In addition, the Expanded System Readiness Review project teams are evaluating operating experience information to assess whether applicable industry'issues have been adequately addressed for applicability to D.C.Cook.Previous Similar Events None NRC FORM 366A (6-1998)}} |
| Corrective ActionsApermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isbeingperformed toidentifyotheradditional electrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAorpipebreakcondition. | |
| Theevaluation willincludeareviewofthecurrentEQProgramdocumentation regarding requirements forNRCFORM366A(6-1998)
| |
| NRCFORM366AU.S.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)4of4TEXT(lfmorespaceisrequired, useadditional copiesofNRCEorm(366A)(17)leaktight electrical enclosures.
| |
| Thisevaluation willbecompleted bySeptember 30,1999.Basedonresultsoftheevaluation, appropriate corrective actionswillbetakentoaddressanyidentified EQdiscrepancies.
| |
| AEP:NRC:1260GH, "Enforcement Actions98-150,98-151,98-152and98-186ReplytoNoticeOfViolation October13,1998",datedMarch19,1999,responded toidentified programmatic weaknesses intheplantDesignandLicensing BasisandtheTrainingandQualification ofpersonnel. | |
| TheEngineering Leadership Planestablishes aconfiguration management programtocontrolplantdesignandanewdesigncontrolprocess,whichincludesdesignverification, designdocumentcontrol,vendortechnical documentation controlandtestingofdesignchanges.AspartoftheRestarteffort,animprovedoperating experience programisbeingdeveloped.
| |
| Inaddition, theExpandedSystemReadiness Reviewprojectteamsareevaluating operating experience information toassesswhetherapplicable industry'issues havebeenadequately addressed forapplicability toD.C.Cook.PreviousSimilarEventsNoneNRCFORM366A(6-1998)}}
| |
LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4| ML17326A091 |
| Person / Time |
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| Site: |
Cook  |
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| Issue date: |
08/16/1999 |
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| From: |
OROURKE B W
AMERICAN ELECTRIC POWER CO., INC. |
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| To: |
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| Shared Package |
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| ML17326A090 |
List: |
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| References |
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| LER-99-019, NUDOCS 9908240285 |
| Download: ML17326A091 (5) |
|
Similar Documents at Cook |
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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17335A5641999-10-18018 October 1999
LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr
ML17335A5531999-10-0707 October 1999
LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented
ML17326A1291999-09-17017 September 1999
LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary
ML17326A1121999-08-27027 August 1999
LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed
ML17326A1011999-08-26026 August 1999
LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs
ML17326A0911999-08-16016 August 1999
LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4
ML17326A0771999-08-0404 August 1999
LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830
ML17326A0741999-07-29029 July 1999
LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves
ML17326A0661999-07-26026 July 1999
LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr
ML17326A0651999-07-22022 July 1999
LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis
ML17326A0491999-07-13013 July 1999
LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr
ML17326A0331999-07-0101 July 1999
LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written
ML17326A0151999-06-18018 June 1999
LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified
ML17325B6311999-06-0101 June 1999
LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions
ML17325B6421999-06-0101 June 1999
LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed
ML17325B6351999-05-28028 May 1999
LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions
ML17265A8231999-05-24024 May 1999
LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made
ML17325B6001999-05-20020 May 1999
LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed
ML17325B5861999-05-10010 May 1999
LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised
ML17325B5811999-05-0404 May 1999
LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared
ML17325B5771999-05-0303 May 1999
LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design
ML17325B5581999-04-16016 April 1999
LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold
ML17325B5471999-04-12012 April 1999
LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation
ML17325B5321999-04-0707 April 1999
LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate
ML17325B5161999-04-0101 April 1999
LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures
ML17325B5221999-03-29029 March 1999
LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing
ML17325B4801999-03-18018 March 1999
LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling
ML17325B4741999-03-18018 March 1999
LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed
ML17325B4571999-02-24024 February 1999
LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors
ML17335A5171999-02-11011 February 1999
LER 99-002-00:on 990112,determined That RCS Pressurizer PORVs Had Not Been Tested,Per Ts.Caused by Inadequate Scheduling Controls Allowing Personnel Error.Surveillance Procedure Was Completed & Updated LER Will Be Submitted
ML17335A5141999-02-10010 February 1999
LER 99-001-00:on 990106,noted That GE Hfa Relays Installed in EDGs May Not Meet Seismic Qualification.Caused by Operating Experience Info Incorrectly Dispositioned in 1985. Updated LER Will Be Submitted by 990405
ML17335A5011999-02-0101 February 1999
LER 98-060-00:on 981231,identified That Rt Sys Response Time Testing Did Not Comply with TS Definition.Caused by Inadequate Procedures.Corrective Actions Will Be Developed & Update to LER Will Be Submitted by 990415.With 990201 Ltr
ML17335A4951999-01-29029 January 1999
LER 98-059-00:on 981230,interim LER -single Failure in Containment Spray Sys Could Result in Containment Spray Ph Outside Design Occurred.Investigation Into Condition Continuing.Update Will Be Submitted by 990514 Ltr
ML17335A4961999-01-27027 January 1999
LER 98-057-00:on 981228,discovered That AFW Valves Were Not Tested IAW Inservice Testing Program.Caused by Failure to Recognize Design Bases Features Re Afws by Personnel. Updated LER Will Be Submittted by 990415.With 990127 Ltr
ML17335A4921999-01-19019 January 1999
LER 98-052-01:on 981128,no Analysis for NSR Sc Manual Loader for Tdafwp Could Be Found in Original Design.Cause Due to All Failure Modes Not Considered When Compressed Air Sys Originally Designed.Performed Review of Components
ML17335A4721999-01-0606 January 1999
LER 98-055-00:on 981207,potential for Condition Outside of Design Bases for Rod Control Sys Was Noted.Caused by Calibration Error Coupled with Single Rod Failure.Condition Rept Investigation Is Ongoing
ML17335A4691999-01-0606 January 1999
LER 98-056-00:on 981211,hot Leg Nozzle Gaps Resulted in Plant Being in Unanalyzed Condition.Analyses Are Being Performed by W to Resolve Problem.Updated LER Will Be Submitted by 990211.With 990106 Ltr
ML17335A4661999-01-0505 January 1999
LER 98-049-00:on 981020,emergency Boron Injection Flow Path Was Inoperable.Caused by Original Design Deficiency. Engineering Evaluation of Event Is Continuing
ML17335A4631999-01-0404 January 1999
LER 98-054-00:on 981202,discovered That at Least One MSSV Had Not Been Reset as Required by Ts.Engineering Is Continuing Review of Extent of Condition for Event.Updated LER Will Be Submitted by 990129.With 990104 Ltr
ML17335A4481998-12-30030 December 1998
LER 98-053-00:on 981130,discovered Use of Inoperable Substitute Subcooling Margin Monitor.Caused by Condition Existing Since Installation of Plant Process Computer in 1992.Updated LER Will Be Submitted.With 981230 Ltr
ML17335A4581998-12-28028 December 1998
LER 98-052-00:on 981128,turbine Driven AFW Pump Speed Controller Failure Mode Occurred.Caused Because Not All Failure Modes Were Considered When Compressed Air Sys Was Originally Designed.Verified Current Design Change Process
ML17335A4281998-12-22022 December 1998
LER 98-051-00:on 981122,reactor Trip Signal from Manual Safety Injection Not Verified as Required by TS Surveillance,Was Discovered.Maintenance Currently Evaluating Significance & Cause of Event
ML17335A4111998-12-17017 December 1998
LER 98-047-00:on 981117,potential for Increase Leakage from Reactor Coolant Pump Seals Was Identified.Util Is Working with W to Resolve Issue.Current Expectations Are to Submit Update to LER by 990215.With 981217 Ltr
ML17335A4141998-12-16016 December 1998
LER 98-058-00:on 981216,postulated High Line Break Could Result in Condition Outside Design Bases for AF Occurred. Caused by Deficiencies Associated with Administration of HELB Program.Analysis of AF Will Be Completed by 990122
ML17335A4181998-12-16016 December 1998
LER 98-050-00:on 980814,ancillary Equipment Installed in Ice Condenser Was Not Designed to Withstand Design Basis Accident/Earthquake Loads.Caused by Lack of Established Design Criteria.Developed Design Criteria
ML17335A3871998-12-11011 December 1998
LER 98-031-01:on 980610,potential Common Mode Failure of RHR Pumps Were Noted.Caused by Inaccurate Values.Accurate Miniflow Numbers Have Been Determined by Flow Testing
ML17335A3821998-12-0808 December 1998
LER 98-039-01 Re EOP Step Conflicts with Small Break LOCA Analysis.Ler 98-039-00 Has Been Canceled.With 981208 Ltr
ML17335A3781998-12-0707 December 1998
LER 98-007-00:on 981106,high Energy Line Break Effects in Auxiliary FW Sys Was Noted.Cause of Event Is Under Investigation & Will Be Completed by 990220.Updated LER Will Be Submitted by 990310.With 981207 Ltr
ML17335A3771998-12-0303 December 1998
LER 98-046-00:on 981103,determined That Afs Was Unable to Meet Design Flow Requirements During Special Test.Caused by Failure to Consider All Aspects of Sys Operation in Design of Suction Basket Strainers.Sys Will Be Redesigned
ML17335A3741998-12-0202 December 1998
LER 97-011-02:on 970822,operation Was Noted Outside Design Bases for ECCS & CSP for Switchover to Recirculation Sump Suction.Caused by Ineffective Change Mgt.Revised Procedure for Switchover 01(02) Ohp 4023.ES-1.3
1999-09-17
[Table view]
Category:RO)
MONTHYEARML17335A5641999-10-18018 October 1999
LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr
ML17335A5531999-10-0707 October 1999
LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented
ML17326A1291999-09-17017 September 1999
LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary
ML17326A1121999-08-27027 August 1999
LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed
ML17326A1011999-08-26026 August 1999
LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs
ML17326A0911999-08-16016 August 1999
LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4
ML17326A0771999-08-0404 August 1999
LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830
ML17326A0741999-07-29029 July 1999
LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves
ML17326A0661999-07-26026 July 1999
LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr
ML17326A0651999-07-22022 July 1999
LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis
ML17326A0491999-07-13013 July 1999
LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr
ML17326A0331999-07-0101 July 1999
LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written
ML17326A0151999-06-18018 June 1999
LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified
ML17325B6311999-06-0101 June 1999
LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions
ML17325B6421999-06-0101 June 1999
LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed
ML17325B6351999-05-28028 May 1999
LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions
ML17265A8231999-05-24024 May 1999
LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made
ML17325B6001999-05-20020 May 1999
LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed
ML17325B5861999-05-10010 May 1999
LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised
ML17325B5811999-05-0404 May 1999
LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared
ML17325B5771999-05-0303 May 1999
LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design
ML17325B5581999-04-16016 April 1999
LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold
ML17325B5471999-04-12012 April 1999
LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation
ML17325B5321999-04-0707 April 1999
LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate
ML17325B5161999-04-0101 April 1999
LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures
ML17325B5221999-03-29029 March 1999
LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing
ML17325B4801999-03-18018 March 1999
LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling
ML17325B4741999-03-18018 March 1999
LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed
ML17325B4571999-02-24024 February 1999
LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors
ML17335A5171999-02-11011 February 1999
LER 99-002-00:on 990112,determined That RCS Pressurizer PORVs Had Not Been Tested,Per Ts.Caused by Inadequate Scheduling Controls Allowing Personnel Error.Surveillance Procedure Was Completed & Updated LER Will Be Submitted
ML17335A5141999-02-10010 February 1999
LER 99-001-00:on 990106,noted That GE Hfa Relays Installed in EDGs May Not Meet Seismic Qualification.Caused by Operating Experience Info Incorrectly Dispositioned in 1985. Updated LER Will Be Submitted by 990405
ML17335A5011999-02-0101 February 1999
LER 98-060-00:on 981231,identified That Rt Sys Response Time Testing Did Not Comply with TS Definition.Caused by Inadequate Procedures.Corrective Actions Will Be Developed & Update to LER Will Be Submitted by 990415.With 990201 Ltr
ML17335A4951999-01-29029 January 1999
LER 98-059-00:on 981230,interim LER -single Failure in Containment Spray Sys Could Result in Containment Spray Ph Outside Design Occurred.Investigation Into Condition Continuing.Update Will Be Submitted by 990514 Ltr
ML17335A4961999-01-27027 January 1999
LER 98-057-00:on 981228,discovered That AFW Valves Were Not Tested IAW Inservice Testing Program.Caused by Failure to Recognize Design Bases Features Re Afws by Personnel. Updated LER Will Be Submittted by 990415.With 990127 Ltr
ML17335A4921999-01-19019 January 1999
LER 98-052-01:on 981128,no Analysis for NSR Sc Manual Loader for Tdafwp Could Be Found in Original Design.Cause Due to All Failure Modes Not Considered When Compressed Air Sys Originally Designed.Performed Review of Components
ML17335A4721999-01-0606 January 1999
LER 98-055-00:on 981207,potential for Condition Outside of Design Bases for Rod Control Sys Was Noted.Caused by Calibration Error Coupled with Single Rod Failure.Condition Rept Investigation Is Ongoing
ML17335A4691999-01-0606 January 1999
LER 98-056-00:on 981211,hot Leg Nozzle Gaps Resulted in Plant Being in Unanalyzed Condition.Analyses Are Being Performed by W to Resolve Problem.Updated LER Will Be Submitted by 990211.With 990106 Ltr
ML17335A4661999-01-0505 January 1999
LER 98-049-00:on 981020,emergency Boron Injection Flow Path Was Inoperable.Caused by Original Design Deficiency. Engineering Evaluation of Event Is Continuing
ML17335A4631999-01-0404 January 1999
LER 98-054-00:on 981202,discovered That at Least One MSSV Had Not Been Reset as Required by Ts.Engineering Is Continuing Review of Extent of Condition for Event.Updated LER Will Be Submitted by 990129.With 990104 Ltr
ML17335A4481998-12-30030 December 1998
LER 98-053-00:on 981130,discovered Use of Inoperable Substitute Subcooling Margin Monitor.Caused by Condition Existing Since Installation of Plant Process Computer in 1992.Updated LER Will Be Submitted.With 981230 Ltr
ML17335A4581998-12-28028 December 1998
LER 98-052-00:on 981128,turbine Driven AFW Pump Speed Controller Failure Mode Occurred.Caused Because Not All Failure Modes Were Considered When Compressed Air Sys Was Originally Designed.Verified Current Design Change Process
ML17335A4281998-12-22022 December 1998
LER 98-051-00:on 981122,reactor Trip Signal from Manual Safety Injection Not Verified as Required by TS Surveillance,Was Discovered.Maintenance Currently Evaluating Significance & Cause of Event
ML17335A4111998-12-17017 December 1998
LER 98-047-00:on 981117,potential for Increase Leakage from Reactor Coolant Pump Seals Was Identified.Util Is Working with W to Resolve Issue.Current Expectations Are to Submit Update to LER by 990215.With 981217 Ltr
ML17335A4141998-12-16016 December 1998
LER 98-058-00:on 981216,postulated High Line Break Could Result in Condition Outside Design Bases for AF Occurred. Caused by Deficiencies Associated with Administration of HELB Program.Analysis of AF Will Be Completed by 990122
ML17335A4181998-12-16016 December 1998
LER 98-050-00:on 980814,ancillary Equipment Installed in Ice Condenser Was Not Designed to Withstand Design Basis Accident/Earthquake Loads.Caused by Lack of Established Design Criteria.Developed Design Criteria
ML17335A3871998-12-11011 December 1998
LER 98-031-01:on 980610,potential Common Mode Failure of RHR Pumps Were Noted.Caused by Inaccurate Values.Accurate Miniflow Numbers Have Been Determined by Flow Testing
ML17335A3821998-12-0808 December 1998
LER 98-039-01 Re EOP Step Conflicts with Small Break LOCA Analysis.Ler 98-039-00 Has Been Canceled.With 981208 Ltr
ML17335A3781998-12-0707 December 1998
LER 98-007-00:on 981106,high Energy Line Break Effects in Auxiliary FW Sys Was Noted.Cause of Event Is Under Investigation & Will Be Completed by 990220.Updated LER Will Be Submitted by 990310.With 981207 Ltr
ML17335A3771998-12-0303 December 1998
LER 98-046-00:on 981103,determined That Afs Was Unable to Meet Design Flow Requirements During Special Test.Caused by Failure to Consider All Aspects of Sys Operation in Design of Suction Basket Strainers.Sys Will Be Redesigned
ML17335A3741998-12-0202 December 1998
LER 97-011-02:on 970822,operation Was Noted Outside Design Bases for ECCS & CSP for Switchover to Recirculation Sump Suction.Caused by Ineffective Change Mgt.Revised Procedure for Switchover 01(02) Ohp 4023.ES-1.3
1999-09-17
[Table view]
Category:TEXT-SAFETY REPORT
MONTHYEARML17335A5641999-10-18018 October 1999
LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr
ML17335A5531999-10-0707 October 1999
LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented
ML17335A5631999-09-30030 September 1999
Monthly Operating Rept for Sept 1999 for DC Cook Nuclear Plant,Unit 1.With 991012 Ltr
ML17335A5621999-09-30030 September 1999
Monthly Operating Rept for Sept 1999 for DC Cook Nuclear Plant,Unit 2.With 991012 Ltr
ML17335A5481999-09-30030 September 1999
Non-proprietary DC Cook Nuclear Plant Units 1 & 2 Mods to Containment Sys W SE (Secl 99-076,Rev 3).
ML17335A5451999-09-28028 September 1999
Rev 1 to Containment Sump Level Design Condition & Failure Effects Analysis for Potential Draindown Scenarios.
ML17326A1291999-09-17017 September 1999
LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary
ML17326A1481999-09-17017 September 1999
Independent Review of Control Rod Insertion Following Cold Leg Lbloca,Dc Cook,Units 1 & 2.
ML17326A1211999-08-31031 August 1999
Monthly Operating Rept for Aug 1999 for Cook Nuclear Plant, Unit 2.With 990915 Ltr
ML17326A1201999-08-31031 August 1999
Monthly Operating Rept for Aug 1999 for Cook Nuclear Plant, Unit 1.With 990915 Ltr
ML17326A1121999-08-27027 August 1999
LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed
ML17326A1011999-08-26026 August 1999
LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs
ML17326A0911999-08-16016 August 1999
LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4
ML17326A0771999-08-0404 August 1999
LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830
ML17335A5461999-08-0202 August 1999
Rev 0 to Evaluation of Cook Recirculation Sump Level for Reduced Pump Flow Rates.
ML17326A0871999-07-31031 July 1999
Monthly Operating Rept for July 1999 for DC Cook Nuclear Plant,Unit 1.With 990812 Ltr
ML17326A0861999-07-31031 July 1999
Monthly Operating Rept for July 1999 for DC Cook Nuclear Plant,Units 2.With 990812 Ltr
ML17326A0741999-07-29029 July 1999
LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves
ML17326A0661999-07-26026 July 1999
LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr
ML17326A0651999-07-22022 July 1999
LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis
ML17326A0491999-07-13013 July 1999
LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr
ML17326A0331999-07-0101 July 1999
LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written
ML17326A0511999-06-30030 June 1999
Monthly Operating Rept for June 1999 for DC Cook Nuclear Plant,Unit 2.With 990709 Ltr
ML17326A0501999-06-30030 June 1999
Monthly Operating Rept for June 1999 for DC Cook Nuclear Plant,Unit 1.With 990709 Ltr
ML17326A0151999-06-18018 June 1999
LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified
ML17325B6421999-06-0101 June 1999
LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed
ML17325B6311999-06-0101 June 1999
LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions
ML17326A0061999-05-31031 May 1999
Monthly Operating Rept for May 1999 for Dcp.With 990609 Ltr
ML17326A0071999-05-31031 May 1999
Monthly Operating Rept for May 1999 for DC Cook Nuclear Plant,Unit 2.With 990609 Ltr
ML17325B6351999-05-28028 May 1999
LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions
ML17265A8231999-05-24024 May 1999
LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made
ML17325B6001999-05-20020 May 1999
LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed
ML17325B5861999-05-10010 May 1999
LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised
ML17325B5811999-05-0404 May 1999
LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared
ML17325B5771999-05-0303 May 1999
LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design
ML17335A5301999-04-30030 April 1999
Monthly Operating Rept for Apr 1999 for DC Cook Nuclear Plant,Unit 1.With 990508 Ltr
ML17335A5291999-04-30030 April 1999
Monthly Operating Rept for Apr 1999 for DC Cook Nuclear Plant,Unit 2.With 990508 Ltr
ML17325B5581999-04-16016 April 1999
LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold
ML17325B5471999-04-12012 April 1999
LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation
ML17325B5321999-04-0707 April 1999
LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate
ML17325B5161999-04-0101 April 1999
LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures
ML17325B5491999-03-31031 March 1999
Monthly Operating Rept for Mar 1999 for DC Cook Nuclear Plant Unit 2.With 990408 Ltr
ML17325B5441999-03-31031 March 1999
Monthly Operating Rept for Mar 1999 for DC Cook Nuclear Plant,Unit 1.With 990408 Ltr
ML17325B5221999-03-29029 March 1999
LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing
ML17325B4801999-03-18018 March 1999
LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling
ML17325B4741999-03-18018 March 1999
LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed
ML17325B5671999-03-0202 March 1999
Summary of Unit 1 Steam Generator Layup Chemistry from 980101 to 990218.
ML17325B4631999-02-28028 February 1999
Monthly Operating Rept for Feb 1999 for DC Cook Nuclear Power Station,Unit 2.With 990308 Ltr
ML17325B4621999-02-28028 February 1999
Monthly Operating Rept for Feb 1999 for DC Cook Nuclear Plant,Unit 1.With 990308 Ltr
ML17325B4571999-02-24024 February 1999
LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors
1999-09-30
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NRC Form 366 U.S.NUCLEAR REGULATORY COMMISSION (6-1996)LICENSEE EVENT REPORT (LER)(See reverse for required number of digits/characters for each block)APPROVEO BY 0MB NO.3(504)104 EXPIRES 05/30/2001 ESTPAATED SVRDEN PER RESPONSE TO COMPLY WITH TI43 MANDATORY eIFORMATION COLLECTION REOVEST: 50 0 HRS.REPORTED LESSONS LEARNED ARE erCORPORATED trfo THE LICENSINO PROCESS ANO FED SACK TO INDVSTRY FORWARD COIVFAENTS REOARDINO SVRDEN ESTSJATE TO THE eIFORMATKNI ANO RECORDS MANAGEMENT SRANCH IT%Faax V.S NVCLEAR REOIAATORY COLSJISSIOH.
WASHNOTON.
OC 20555000I, ANO TO THE PAPERWORK REDVCTION PROJECT (3I500IDII OFFCE OF ScrNAOEMENT AND SVOOET WASHrNOTONi DC 20500 FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKETNUMBER(2) 05000-315 PAOE (3)1 of4 TITLE (4)Victoreen Containment High Range Radiation Monitors Not Environmentally Qualified to Withstand Post-LOCA Conditions EVENT DATE (5)LER NUMBER (6)REPORT DATE (7)OTHER FACILITIES INVOLVED (8)MONTH DAY 07 16 YEAR 1999 YEAR SEQUENTIAL NUMBER 1999-019 REVISION NUMBER 00 MONTH 08 DAY 16 YEAR 1999 FACILITY NAME D.C.Cook-Unit 2 FACILITY NAME DOCKET NUMBER 05000-316 DOCKET NUMBER OPERATING MODE (9)THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR Ii: (Check one or mor 20.2201 (b)20.2203(a)(2)(v) 50.73(a)(2)(i) e)(11)50.73(a)(2)(viii)
POWER LEVEL (10)0 20.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1) 50.36(c)(2)
LICENSEE CONTACT FOR THIS LER (12)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50,73(a)(2)(x) 73.71 OTHER Speo/Y in Abstract betorv or nNRCForm3SSA NAME Ms.Brenda W.O'ourke, Compliance Engineer TELEPHONE NUMBER 0ndrrde Area Code)(616)465-5901 x2604 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13 CAUSE SYSTEM COMPON NT MAIJUFACTUR R REPORTABLE TO EPIX CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO EPIX SUPPLEMENTAL REPORT EXPECTED 14 YES IIYes com lete EXPECTED SUBMISSION DATE X EXPECTED SUBMISSION DATE 15 MONTH DAY YEAR Abstract (Limit to 1400 spaces, I.e.~approximately 15 single-spaced typewritten lines)(16)On May 21, 1999, during an Environmental Qualification (EQ)program self-assessment, preliminary review identified that the containment high range radiation monitors (HRRM)may not be environmentally qualified to withstand the effects of a Loss of Coolant Accident (LOCA).The self-assessment found that D.C.Cook's evaluation of NRC Information Notice (IN)97-45,"Environmental Qualification Deficiency for Cables and Containment Penetration Pigtails," failed to adequately address the susceptibility of the containment HRRMs to moisture intrusion.
IN'97-45 identified that electrical signal cables and connectors found in HRRMs are sensitive to moisture exposure effects, such as from a LOCA or pipe break event.Industry events have identified that moisture intrusion into the cable jacket and connectors has resulted in erratic indication of radiation levels and loss of HRRM function.Based on continued evaluation of the EQ deficiencies, the Unit 1 and 2 HRRMs were declared inoperable on July 16, 1999.The apparent cause was inadequate design control.In response to NRC IN 89-63, a design change to the HRRM system added drainage features to several components.
However, the EQ requirement that the HRRM system be leaktight against possible moisture intrusion was not considered.
A permanent solution for the susceptibility of the HRRMs to moisture intrusion will be developed to support HRRM operability in Modes 1-4.Options for the permanent solution are currently under review and the method selected will be implemented prior to Mode 4 for each unit.An evaluation of the as-built configuration for other low signal current application EQ equipment is also being performed to identify other electrical equipment that may be susceptible to moisture intrusion due to a LOCA and/or pipe break condition.
This evaluation will be completed by September 30, 1999.This condition has minimal safety significance due to the availability of alternate post-accident radiation monitoring instrumentation.
'3)'T)08240285 3)'T)08'PDR ADOCK 050003i 5 S PDR
NRC FORM 366A U.s.NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKET NUMBER(2)05000-315 YEAR LER NUMBER (6)SEQUENTIAL NUMBER REVISION NUMBER PAGE (3)2of4 TEXT (lf more space is required, use adCh'tional copies of NRC Form (366A)(17)Conditions Prior to Event Unit 1 was in Mode 5, Cold Shutdown Unit 2 was in Mode 5, Cold Shutdown 1999-019 00 Descri tion of Event On May 21, 1999, during an Environmental Qualification (EQ)program self-assessment, preliminary review identified that the Radiation Monitoring System's (RMS)[EIIS:IL]Victoreen containment high range radiation monitors (HRRM)may not be environmentally qualified to withstand the effects of a Loss of Coolant Accident (LOCA).The self-assessment found that D.C.Cook's evaluation of NRC Information Notice (IN)97-45,"Environmental Qualification Deficiency for Cables and Containment Penetration Pigtails," failed to adequately address the susceptibility of the containment HRRMs to moisture intrusion.
IN 97-45 identified that electrical signal cables[EIIS:CBL1]
and connectors
[EIIS:CON]
found in HRRMs are sensitive to moisture exposure effects, such as from a LOCA or pipe break event.Industry events have identified that moisture intrusion into the cable jacket and connectors can result in erratic indication of radiation levels in containment.
In addition, Supplement 1 to IN 97-45 identified that HRRMs have experienced significant positive and negative current flow as a result of induced currents in Rockbestos coaxial signal cables when exposed to high temperature transient conditions.
As a result, the detection function of the HRRMs would be impacted.Recent evaluation of the HRRM EQ deficiencies identified that in response to NRC IN 89-63,"Possible Submergence of Electrical Circuits Located Above the Flood Level Because of Water Intrusion and Lack of Drainage," D.C.Cook added drainage features (e.g., weep holes and slits in sealtite flex conduit)to the HRRM electrical enclosures (conduit and junction boxes[EIIS:JBX])
in containment.
However, this resulted in a non-leaktight HRRM configuration, potentially exposing the moisture sensitive components to LOCA conditions.
Based on above information, it was concluded that the Unit 1 and 2 HRRMs would not be capable of performing their intended design function.As a result, on July16, 1999, the HRRMs were declared inoperable at 1558 hours0.018 days <br />0.433 hours <br />0.00258 weeks <br />5.92819e-4 months <br />.Cause of Event The apparent cause was inadequate design control.In response to NRC IN 89-63, a design change to the HRRM system added drainage features to several components.
However, the EQ requirement that the HRRM system be leaktight against possible moisture intrusion was not considered.
Subsequent opportunities to identify this condition were missed during D.C.Cook's evaluation of IN 97-45 and its supplement.
The concerns identified in the Information Notice were determined not to be applicable to D.C.Cook because the HRRMs use Brand Rex signal cabling versus Rockbestos cabling as described in IN 97-45.Anal sis of Event This LER is being submitted in accordance with the requirements of 10CFR50.73(a)(2)(i)(B) for a condition prohibited by plant Technical Specifications.
TS 3.3.3.1 requires the containment HRRMs to be operable in Modes 1-4.UFSAR Section 11.3, states that the Radiation Monitoring System is designed to perform two basic functions:
1)warn of any radiation hazards which might develop, and 2)give early warning which might lead to a radiation hazard or plant damage.The RMS instruments are located at selected points in and around the plant to detect, compute, and record radiation levels.The components of the RMS are designed to operate during all expected environmental conditions for normal operation, and specific components are designed to operate during adverse or accident conditions.
The subject radiation monitors include the Victoreen containment high range radiation monitors (1-VRA-1310/1410 and 2-VRA-2310/2410) which provide indication of containment radiation levels during post-LOCA conditions and are utilized in assessing possible core damage.NRC FORM 366A (6-1998)
NRC FORM 366A U.s.NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 OOCKET NUMBER(2)05000-315 YEAR 1999 LER NUMBER (6)SEQUENTIAL NUMBER 019 REVISION NUMBER 00 PAGE (3)3of4 TEXT (if more space is required, use addi(tonal copies of NRC Form (366A)(17)A typical HRRM consists of a detector, associated Brand Rex triaxial cabling, conduit, junction boxes and Amphenol connectors.
Amphenol connectors are located at the penetration pigtails and other electrical cable connections, and at a junction box located at the top of the containment penetration flood-up tubes.Each Amphenol connector is enclosed in a Raychem boot seal, with the associated detector cabling contained within a conduit system.The junction box and conduit system contain weep holes which were added in response to NRC IN 89-63.EQ testing performed by Victoreen in 1978 experienced numerous failures in attempting to qualify a connector assembly for in-containment LOCA use.The only documented successful simulated LOCA testing was for cable and connectors that were enclosed in leaktight conduits.This configuration prevents moisture intrusion into the cable and connectors during post-LOCA conditions.
NRC IN 97-45, identified potential EQ deficiencies associated with Rockbestos coaxial cables and Amphenol connectors used in containment HRRM systems.Subsequent vendor EQ testing concluded that moisture could permeate the HRRM coaxial cable jacket during p LOCA and cause partial shorting of the monitor signal at the connectors.
Because of the small signal current output from the HRRMs (nominally pico-amperes), partial shorting of the signal could result in loss of HRRM function.In addition, Supplement 1 identified that HRRMs cabling is susceptible to thermally-induced currents as a result of extreme temperature transients.
Thermally-induced currents have been found to impact the accuracy of the HRRMs.E In 1990, drainage features were added to D.C.Cook's HRRM system in response to NRC IN 89-63.Industry concerns were identified regarding the lack of drainage holes in containment electrical enclosures that may become submerged during a LOCA event.Without the appropriate drainage, water could collect inside the enclosures and cause shorting of the electrical components contained in the enclosures.
Although D.C.Cook's HRRM conduit system contains weep holes, the moisture intrusion potential of the subject connectors is much more limited than that described in the Victoreen test reports and NRC IN 97-45.In these tests, the coaxial cable and sealed connectors were directly exposed to steam and spray conditions, whereas D.C.Cook's cable and sealed connectors are contained within a conduit system.Because of the additional protection given by the conduit system, the maximum amount of moisture that could potentially come in contact with the connectors is limited by the internal free air space of the conduit.During the increasing containment pressure portion of a LOCA transient, the steam would fill the conduit, displacing the air inside the conduit and result in the trapped steam condensing on the colder cable and conduit internal walls.This amount of moisture intrusion is much more limited than would occur in an open system (i.e., with no conduit enclosure).
The design function of the containment HRRMs is to provide operators with post-LOCA indication of containment radiation levels which are also utilized in assessing possible core damage.Although the identified EQ deficiencies could render the HRRMs inoperable following a LOCA, alternative means of performing this monitoring function exist through other post-accident monitoring instrumentation.
This includes the post-accident monitoring system and the post-accident grab sample pallet in accordance with plant emergency procedures.
Based on the above information, the identified condition has minimal safety significance due to the availability of alternate post-accident radiation monitoring instrumentation.
Corrective Actions A permanent solution for the susceptibility of the HRRMs to moisture intrusion will be developed to support HRRM operability in Modes 1-4.Options for the permanent solution are currently under review and will be implemented prior to Mode 4 for each unit.An evaluation of the as-built configuration for other low signal current application EQ equipment is being performed to identify other additional electrical equipment that may be susceptible to moisture intrusion due to a LOCA or pipe break condition.
The evaluation will include a review of the current EQ Program documentation regarding requirements for NRC FORM 366A (6-1998)
NRC FORM 366A U.S.NUCLEAR REGULATORY COMMISSION (6-1 998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1)Cook Nuclear Plant Unit 1 DOCKET NUMBER(2)05000-315 YEAR 1999 LER NUMBER (6)SEQUENTIAL NUMBER 019 REVISION NUMBER 00 PAGE (3)4 of 4 TEXT (lf more space is required, use additional copies of NRC Eorm (366A)(17)leaktight electrical enclosures.
This evaluation will be completed by September 30, 1999.Based on results of the evaluation, appropriate corrective actions will be taken to address any identified EQ discrepancies.
AEP:NRC:1260GH,"Enforcement Actions98-150, 98-151, 98-1 52 and 98-186 Reply to Notice Of Violation October 13, 1998", dated March 19, 1999, responded to identified programmatic weaknesses in the plant Design and Licensing Basis and the Training and Qualification of personnel.
The Engineering Leadership Plan establishes a configuration management program to control plant design and a new design control process, which includes design verification, design document control, vendor technical documentation control and testing of design changes.As part of the Restart effort, an improved operating experience program is being developed.
In addition, the Expanded System Readiness Review project teams are evaluating operating experience information to assess whether applicable industry'issues have been adequately addressed for applicability to D.C.Cook.Previous Similar Events None NRC FORM 366A (6-1998)