RG1.082 失水事故后长期在循环冷却的水源 2003

RegulatoryguidesareissuedtodescribeandmakeavailabletothepublicsuchinformationasmethodsacceptabletotheNRCstaffforimplementingspecificpartsoftheNRC’sregulations,techniquesusedbythestaffinevaluatingspecificproblemsorpostulatedaccidents,anddataneededbytheNRCstaffinitsreviewofapplicationsforpermitsandlicenses.Regulatoryguidesarenotsubstitutesforregulations,andcompliancewiththemisnotrequired.MethodsandsolutionsdifferentfromthosesetoutintheguideswillbeacceptableiftheyprovideabasisforthefindingsrequisitetotheissuanceorcontinuanceofapermitorlicensebytheCommission.Thisguidewasissuedafterconsiderationofcommentsreceivedfromthepublic.Commentsandsuggestionsforimprovementsintheseguidesareencouragedatalltimes,andguideswillberevised,asappropriate,toaccommodatecommentsandtoreflectnewinformationorexperience.WrittencommentsmaybesubmittedtotheRulesandDirectivesBranch,ADM,U.S.NuclearRegulatoryCommission,Washington,DC20555-0001.Regulatoryguidesareissuedintenbroaddivisions:1,PowerReactors;2,ResearchandTestReactors;3,FuelsandMaterialsFacilities;4,EnvironmentalandSiting;5,MaterialsandPlantProtection;6,Products;7,Transportation;8,OccupationalHealth;9,AntitrustandFinancialReview;and10,General.Singlecopiesofregulatoryguides(whichmaybereproduced)maybeobtainedfreeofchargebywritingtheDistributionServicesSection,U.S.NuclearRegulatoryCommission,Washington,DC20555-0001,orbyfaxto(301)415-2289,[e-mail]ideandotherrecentlyissuedguidesareavailableatNRC’shomepageat(DraftwasissuedasDG-1107)WATERSOURCESFORLONG-TERMRECIRCULATIONCOOLINGFOLLOWINGALOSS-OF-COOLANTACCIDENTA.INTRODUCTIONGeneralDesignCriterion(GDC)35,“EmergencyCoreCooling”;GDC38,“ContainmentHeatRemoval”;andGDC41,“ContainmentAtmosphereCleanup,”ofAppendixA,“GeneralDesignCriteriaforNuclearPowerPlants,”to10CFRPart50,“DomesticLicensingofProductionandUtilizationFacilities,”requirethatsystemsbeprovidedtoperformspecificfunctions,i.e.,emergencycorecooling,containmentheatremoval,andcontainmentatmospherecleanupfollowingapostulateddesignbasisaccident.PursuanttoGDC36,“InspectionofEmergencyCoreCoolingSystem”;GDC39,“InspectionofContainmentHeatRemovalSystem”;andGDC42,“InspectionofContainmentAtmosphereCleanupSystems”ofAppendixAto10CFRPart50,thesesystemsmustbedesignedtopermitappropriateperiodicinspectionofimportantcomponents.PursuanttoGDC37,“TestingofEmergencyCoreCoolingSystem”;GDC40,“TestingofContainmentHeatRemovalSystem”;andGDC43,“TestingofContainmentAtmosphereCleanupSystems”ofAppendixAto10CFRPart50,thesesystemsmustbedesignedtopermitappropriateperiodictestingtoensuretheirintegrityandoperability.Inaddition,GDC1,QualityStandardsandRecords,ofAppendixAto10CFRPart50requiresthatstructures,systems,andcom-ponentsimportanttosafetybedesigned,fabricated,erected,andtestedtoqualitystandardscommensuratewiththeimportanceofthesafetyfunctionstobeperformed.1.82-2ThisguidedescribesmethodsacceptabletotheNRCstaffforimplementingtheserequirementswithrespecttothesumpsandsuppressionpoolsperformingthefunctionsofwatersourcesforemergencycorecooling,containmentheatremoval,orcontainmentatmospherecleanup.Theguidealsoprovidesguidelinesforevaluatingtheadequacyoftheavailabilityofthesumpandsuppressionpoolforlong-termrecirculationcoolingfollowingaloss-of-coolantaccident(LOCA).Thisguideappliestolight-water-cooledreactors.AdditionalinformationisprovidedinNRCBulletin2003-01,“PotentialImpactofDebrisBlockageonEmergencySumpRecirculationatPressurized-WaterReactors”;NRCBulletin96-03,”PotentialPluggingofEmergencyCoreCoolingSuctionStrainersbyDebrisinBoilingWaterReactors”;NRCBulletin95-02,“UnexpectedCloggingofaResidualHeatRemovalPumpStrainerWhileOperatinginSuppressionPoolCoolingMode”;NRCBulletin93-02,“DebrisPluggingofEmergencyCoreCoolingSuctionStrainers”;Supplement1toNRCBulletin93-02,“DebrisPluggingofEmergencyCoreCoolingSuctionStrainers”;GenericLetter85-22,“PotentialforLossofPost-LOCARecirculationCapabilityDuetoInsulationDebrisBlockage”;andGenericLetter97-04,“AssuranceofSufficientNetPositiveSuctionHeadforEmergencyCoreCoolingandContainmentHeatRemovalPumps.”Thisregulatoryguidehasbeenrevisedtoenhancethedebrisblockageevaluationguidanceforpressurizedwaterreactors.ResearchaftertheissuanceofRevision2indicatedthatthepreviousguidancewasnotcomprehensiveenoughtoensureadequateevaluationofapressurizedwaterreactor(PWR)plant’ssusceptibilitytothedetrimentaleffectscausedbydebrisaccumulationondebrisinterceptors(e.g.,trashracksandsumpscreens).ThesectionspertainingtoPWRshavebeenchanged,andminorchangeshavebeenmadetothesectionsonboilingwaterreactors(BWRs)tomakethemconsistentwithcurrentstaffpositionsasdescribedintheSafetyEvaluationontheBoilingWaterReactorOwnersGroup’s(BWROG’s)UtilityResolutionGuide(URG)forECCSSuctionStrainerBlockage(1998).ThisregulatoryguidehasalsobeenrevisedtoincludeguidancepreviouslyprovidedinRegulatoryGuide1.1,“NetPositiveSuctionHea