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RBSUSARRevision14 11.1-1September2001CHAPTER11RADIOACTIVEWASTEMANAGEMENT11.1SOURCETERMSTheexpectedreactorcoolantandmainsteamactivitiesformthebasisforestimatingtheaveragequantityofradioactivematerial releasedtotheenvironmentandreflectnormaloperating conditions,includingoperationaloccurrences.Thesedataare presentedinTable11.1-1andarebasedonmethodswhichare consistentwithNUREG-0016,Rev.1andrepresentfailedfuel conditionscorrespondingtoanoffgasreleaserateof 50,000µCi/secat30mindelay (10).ParametersusedtodeterminetheexpectedsourcetermsarelistedinTable11.1-2.14ThedesignbasisradioactivemateriallevelsinthereactorcoolantandmainsteamarealsopresentedinTable11.1-1.These dataconservativelyrepresenttheshielding,ventilation,and radwastesystemfailureanalysesdesignbasisfissionproduct sourceterms.Designfailedfuelconditionscorrespondtoanoffgasreleaserateof100
µCi/sec/MWt,or304,000
µCi/sec,at30mindelayandaredevelopedbyscalingupfromexpectedNUREG-0016sourcetermdata.Inaddition,thedesignsource termsinTable11.1-1takeintoconsiderationplantoperation withhydrogenwaterchemistryandtheGEdesignbasisdata describedinSection11.1.1andTables11.1-3,11.1-5,11.1-6, 11.1-7,and11.1-8.Table11.1-1presentsthehigher concentrationsforagivenisotopefromeithertheadjusted NUREG-0016dataortheGEdata,andthus,representsa conservativedatasetforuseindesignbasisevaluations.The NUREG-0016datareflectsahalogen(iodineandbromine)carry-overfractionof1.5%fordeterminingthenormalwaterchemistry reactorwaterhalogenconcentrationsandaconservative applicationof4%carry-overindeterminingthehydrogenwater chemistryreactorsteamhalogenconcentrations.
1411.1.1GeneralElectricReactorCoolantandMainSteamDataGEhasevaluatedradioactivematerialsources(activationproductsandfissionproductreleasefromfuel)inoperating boilingwaterreactors(BWRs)overthepastdecade.Thesesource termsarereviewedandperiodicallyrevisedtoincorporate up-to-dateinformation.Theinformationprovidedinthissectiondefinesthedesignbasisradioactivemateriallevelsinthereactorwater,steam,andoff gas.Thevariousradioisotopeslistedhavebeengroupedas fissionproducts,coolantactivationproducts,andnoncoolant activationproducts.Thefissionproductactivitylevelsare basedonmeasurementsofBWRwaterandoffgasatseveral stationsthroughmid-1971.Emphasiswasplacedonobservations
made at KRB and Dresden RBSUSAR 11.1-2August1987Unit2.Thedesignbasisradioactivemateriallevelsdonotnecessarilyincludealltheradioisotopesobservedorpredicted theoreticallytobepresent.Theradioisotopesincludedare consideredsignificanttooneormoreofthefollowingcriteria:1.Plantequipmentdesign2.Shieldingdesign 3.Understandingofsystemoperationandperformance 4.Measurementpracticability 5.Evaluationofradioactivematerialreleasestothe environment.Forhalogens,radioisotopeswithhalf-liveslessthan3minwereomitted.Forotherfissionproductradioisotopesinreactor water,radioisotopeswithhalf-liveslessthan10minwerenot
considered.11.1.1.1FissionProducts NobleRadiogasFissionProductsThenobleradiogasfissionproductsourcetermsobservedinoperatingBWRsaregenerallycomplexmixtureswhosesourcesvary fromminisculedefectsincladdingtominutequantitiesof "tramp"uraniumonexternalcladdingsurfaces.Therelative concentrationsoramountsofnobleradiogasisotopesrelativeto theothernoblegasisotopescanbedescribedasfollows:Equilibrium:R gK 1 yRecoil:R gK 2 yThetermsintheseandsucceedingequationsaredefinedinthe nomenclaturesection.TheconstantsKandKdescribethe fractionsofthetotalfissionsthatareinvolvedineachofthe releases.Theequilibriumandrecoilmixturesarethetwo extremesofthemixturespectrumthatarephysicallypossible.
Theequilibriummixtureresultswhenasufficienttimedelay betweenthefissioneventandthetimeofreleaseofthe radiogasesfromthefueltothecoolantfortheradiogasesto approachequilibriumlevelsinthefuel.Whenthereisnodelay orimpedancebetweenthefissioneventandthereleaseofthe radiogases,therecoilmixtureisobserved.
RBSUSAR 11.1-3August1987PriortoVallecitosBoilingWaterReactorandDresdenUnit1experience,itwasassumedthatnobleradiogasleakagefromthe fuelwouldbetheequilibriummixtureofthenobleradiogases presentinthefuel.VallecitosBoilingWaterReactorandearlyDresdenUnit1experienceindicatedthattheactualmixturemostoftenobserved approachedadistributionwhichwasintermediateincharactertothetwoextremes (1).Thisintermediatedecaymixturewastermedthe"diffusion"mixture.Itmustbeemphasizedthatthisdiffusionmixtureismerelyonepossiblepointonthemixture spectrumrangingfromtheequilibriumtotherecoilmixtureand doesnothavetheabsolutemathematicalandmechanisticbasisfor thecalculationalmethodspossibleforequilibriumandrecoil mixtures.However,thisdiffusiondistributionpatternisdescribedasfollows (2):Diffusion:R gK 3 y0.5TheconstantKdescribesthefractionoftotalfissionsthatareinvolvedintherelease.Ascanbeseen,theexponentofthedecayconstant,,ismidwaybetweenthatofequilibrium,0,andrecoil,1.Thediffusionpatternvalueof0.5wasoriginallyderivedfromdiffusiontheory.AlthoughthepreviouslydescribeddiffusionmixturewasusedbyGEasabasisfordesignsince1963,thedesignbasisrelease magnitudeusedhasvariedfrom0.5Ci/secto0.1Ci/secas measuredafter30-mindecay(t=30min).(Thenobleradiogas sourcetermrateafter30-mindecayhasbeenusedasa conventionalmeasureofthedesignbasisfuelleakageratesince itisconvenientlymeasurableatexistingBWRplantsandwas consistentwiththenominaldesignbasis30-minoffgasholdup systemusedonanumberofplants.)Sinceabout1967,thedesign basisreleaseratefromthecorewasestablishedatanannual averageof0.1Ci/sec(t=30min).Theexpectedannualaverageis significantlybelowthedesignbasisannualaverage.Thisdesign valuewasselectedonthebasisofoperatingexperiencerather thanpredictiveassumptions.Severaljudgmentfactors,including thesignificanceofenvironmentalrelease,reactorwater radioisotopeconcentrations,liquidwastehandlingandeffluent disposalcriteria,buildingaircontamination,shieldingdesign, andturbineandothercomponentcontaminationaffecting maintenance,havebeenconsideredinestablishingthislevel.Althoughnobleradiogassourcetermsfromfuelabove0.1Ci/sec(t=30min)canbetoleratedforreasonable RBSUSAR 11.1-4August1987periodsoftime,longtermoperationatsuchlevelswouldbeundesirable.Continualassessmentofthisvalueismadeonthe basisofactualoperatingexperienceinBWRs (9).Whilethenobleradiogassourcetermmagnitudewasestablishedat 0.1Ci/sec(t=30min),itwasrecognizedthattheremaybeamore statisticallyapplicabledistributionforthenobleradiogas mixture.SufficientdatawereavailablefromKRBoperationsfrom 1967tomid-1971alongwithDresdenUnit2datafromoperationin 1970andseveralmonthsin1971tomoreaccuratelycharacterize thenobleradiogasmixturepatternfromanoperatingBWR.Thebasicequationforeachradioisotopeusedtoanalyzethecollecteddatais:
R g=K g ym (1-e-)(e-t)(11.1-1)WiththeexceptionofKr-85withahalf-lifeof10.74yr,thenobleradiogasfissionproductsinthefuelareessentiallyatan equilibriumconditionafteranirradiationperiodofseveral months(rateofformationisequaltorateofdecay).Therefore,theterm(1-e
-T)approaches1andcanbeneglectedwhenthereactorhasbeenoperatingatsteadystateforlongperiodsof time.Theterm(e
-T)isusedtoadjustthereleasesfromthefuel(t=0)tothedecaytimeforwhichvaluesareneeded.Historically,t=30minhasbeenused.Whendiscussinglong steady-stateoperationandleakagefromthefuel(t=0),the followingsimplifiedformofEquation11.1-1canbeusedto describetheleakageofeachnobleradiogasisotope:
R g=K g ym (11.1-2)Theconstant,K g,describesthemagnitudeoftotalleakage.Therateofnobleradiogasleakagewithrespecttoeachother(composition)isexpressedintermsofthedecayconstantterm,,andthefissionyieldfraction,y.DividingbothsidesofEquation11.1-2byyandtakingthe logarithmofbothsidesresultsinthefollowingequation:log(R g/y)=mlog()+log(K g)(11.1-3)
RBSUSARRevision14 11.1-5September2001Equation11.1-3representsastraightlinewhenlog(R g/y)isplottedversuslog();mistheslopeoftheline.ByfittingactualdatafromKRBandDresdenUnit2(usingleastsquarestechniques)thevalueofmcanbeobtained.WithradiogasleakageatKRBoverthenearly5-yrperiodvaryingfrom0.001to 0.056Ci/sec(t=30min)andwithradiogasleakageatDresdenUnit 2varyingfrom0.001to0.169Ci/sec(t=30min),theaveragevalueformof0.4withastandarddeviationof
+/-0.07wasdetermined(Fig.11.1-1).Asshowninthisfigure,variationsinmwereobservedintherangem=0.1tom=0.6.Afterestablishingthevalueofm=0.4,thevalueofK gcanbecalculatedbyselectingavalueforR g;withR g at30min=100,000
µCi/sec,K gis2.6x10 7andEquation11.1-1 becomes: R g=2.6x10 7 y0.4 (1-e-T)(e-t)(11.1-4)Thisupdatednobleradiogassourcetermmixturehasbeentermedthe"1971Mixture"todifferentiateitfromthediffusion
mixture.ThenoblegassourcetermforeachradioisotopecanbecalculatedfromEquation11.1-4.Theresultantsourcetermsarepresented inTable11.1-3asleakagefromfuel(t=0)andafter30-min decay.WhileKr-85canbecalculatedusingEquation11.1-4,the numberofconfirmingexperimentalobservationswaslimitedbythe difficultyofmeasuringverylowreleaseratesofthisisotope.
Therefore,thetableprovidesanestimatedrangeforKr-85based onactualmeasurements.RadiohalogenFissionProducts14Normaloperationalreleasestotheprimarycoolantareexpectedtobeapproximately25,000
µCi/secofthe13commonlyconsiderednoblegases,asevaluatedat30min,and100
µCi/secofI-131.Thesevaluescanbecomparedtothedesignbasevalueof 100,000Ci/secforthesummationofthesame13and700
µCi/secforI-131.Table11.1-4liststhesourcetermsreleasedtothereactorpressurevesselasaconsequenceofaPowerIsolation Event(MSIVclosureatpower),whichistheonlyanticipated operationaloccurrenceinwhichsignificantactivityisexpected tobereleased.
14Historically,theradiohalogendesignbasissourcetermwas establishedbythesameequationasthatusedfornoble radiogases.Inafashionsimilartothatusedwithgases,a RBSUSAR 11.1-6August1987simplifiedequationcanbeshowntodescribethereleaseofeachhalogenradioisotope:
R h=K h yn (11.1-5)Theconstant,K h,describesthemagnitudeofthetotalleakagefromthefuel.Therateofhalogenradioisotopereleaseswith respecttoeachother(composition)isexpressedintermsofthefissionyield,y,andthedecayconstant,.Aswasdonewiththenobleradiogases,theaveragevaluewasdeterminedforn.
Theaveragevaluefornis0.5withastandarddeviationof
+/-0.19(Fig.11.1-2).Ascanbeseenfromthisfigure,variationsinnwereobservedintherangefromn=0.1ton=0.9.Asmentioned,itappearsthattheuseofthepreviousmethodofcalculatingradiohalogenleakagefromfuelisoverly conservative.Fig.11.1-3relatesKRBandDresdenUnit2noble radiogasreleasesversusI-131leakage.WhileUnit2dataduring theperiodAugust1970toJanuary1971showarelationship betweennobleradiogasandI-131leakageunderonefuel condition,therewasnosimplerelationshipforallfuel conditionsexperienced.Also,duringthisperiod,highradiogas leakageswerenotaccompaniedbyhighradioiodineleakagefrom thefuel.ExceptforoneKRBdatumpoint,allsteady-stateI-131 leakagesobservedatKRBorDresdenUnit2wereequaltoorlessthan505µCi/sec.EvenatDresdenUnit1inMarch1965,whenseveredefectswereexperiencedinstainlesssteelcladfuel,I-131leakagesgreaterthan500
µCi/secwerenotexperienced.Fig.11.1-3showsthatthesehigherradioiodineleakagesfromthefuelwererelatedtonobleradiogassourcetermsoflessthanthe designbasisvalueof0.1Ci/sec(t=30min).Thismaybe partiallyexplainedbyinherentlimitationsduetointernalplant operationalproblemsthatcausedplantderating.Ingeneral,one wouldnotanticipatecontinuedoperationatfullpowerforany significanttimeperiodwithfuelcladdingdefectswhichwouldbe indicatedbyI-131leakagefromthefuelinexcessof 700µCi/sec.Whenhighradiohalogenleakagesareobserved,otherfissionproductswillbepresentingreateramounts.Byusingthesejudgmentfactorsandexperiencetodate,thedesignbasisradiohalogensourcetermsfromfuelwereestablishedbasedonanI-131leakageof700
µCi/sec.Thisvalue(Fig.11.1-3)isconsistentwiththeexperiencedataandthedesignbasisnobleradiogassourcetermof0.1Ci/sec(t=30min) withtheI-131designbasissource RBSUSARRevision14 11.1-7September2001termestablished,K hequals2.4x10 7,andthehalogenradioisotopereleasecanbeexpressedbythefollowingequation:
R h=2.4x10 7 y0.5 (1-e-T)(e-t)(11.1-6)ConcentrationsofradiohalogensinreactorwaterarelistedinTable11.1-5andcanbecalculatedusingthefollowingequation:
R h C h=(11.1-7)M(++)TermsusedinEquation11.1-7aredefinedinthenomenclature
section.14Althoughcarryoverofmostsolubleradioisotopesfromreactorwatertosteamisobservedtobe<0.1percent(<0.001fraction),
theobservedcarryoverforradiohalogenshasvariedfrom0.1 percenttoabout2percentonnewerplants.Theaverageof observedradiohalogencarryovermeasurementshasbeen1.2percent byweightofreactorwaterinsteamwithastandarddeviationof
+/-0.9.Fornormalwaterchemistry,inthepresentsourcetermdefinition,aradiohalogencarryoverdesignbasisof2percent(0.02fraction)isused.Hydrogenwaterchemistryhasbeenimplementedtocontrolthepotentialforstresscorrosioncrackingofvesselinternals.
Hydrogenisinjectedintothefeedwatertoreducetheradiolytic productionofoxygenandhydrogenperoxideandtopromote recombinationofresidualoxidants.UnderHWCandconditionsof lowcopperinthefeedwater,thecarry-overfractionforhalogen isotopescanbeenhancedasisreportedinReference11.1-10.
Thiswillreducetheactivitiesofiodineisotopesinthereactor waterandincreasetheiractivitiesinthesteam.Tobound operationwithandwithouthydrogeninjection,reactorwater halogenactivitiesarecalculatedfornormalwaterchemistry assuming2%carry-over.GEhasdeterminedtheNWCiodinecarry-overinthesteamattheRBStobe2.9%.AssumingthatRBSwillbehaveliketheplant withsimilarfeedwatercopperconcentrationsstudiedinReference 11.1-10,theestimatedhalogencarry-overwithhydrogeninjection isexpectedtoincreaseto3%,representinganoperationally anticipatedincreaseof3.5%fromnormaltohydrogenwater chemistryoperatingconditions.
14 RBSUSAR 11.1-7aAugust1987OtherFissionProductsTheobservationsofotherfissionproducts(andtransuranicnuclides,includingNp-239)inoperatingBWRsarenotadequately correlatedbysimpleequations.Fortheseradioisotopes,design basisconcentrationsinreactorwaterhavebeenestimated conservativelyfromexperiencedata(Table11.1-6).Carryoverof theseradioisotopesfromthereactorwatertothesteamis estimatedtobe<0.1percent(<0.001fraction).Inadditionto carryover,however,decayofnobleradiogasesinthesteam leavingthereactorresultsinproductionofnoblegasdaughter radioisotopesinthesteamandcondensatesystems.Somedaughterradioisotopes(forexample,yttriumandlanthanum)werenotlistedasbeinginreactorwater.Theirindependent leakagetothecoolantisnegligible;however,these radioisotopesmaybeobservedinsomesamplesinequilibriumor approachingequilibriumwiththeparentradioisotope.
RBSUSARRevision14 11.1-7bSeptember2001THISPAGELEFTINTENTIONALLYBLANK RBSUSAR 11.1-8August1987ExceptforNp-239,traceconcentrationsoftransuranicisotopeshavebeenobservedononlyafewsampleswhereextensiveand complexanalyseswerecarriedout.Thepredominantalphaemitter presentinreactorwaterisCm-242atanestimatedconcentrationof10-6µCi/secorlesswhichisbelowthemaximumconcentrationindrinkingwaterapplicabletocontinuoususebythegeneralpublic.Theconcentrationofalphaemittingplutonium radioisotopeismorethanoneorderofmagnitudelowerthanthat ofCm-242.Plutonium-241(abetaemitter)mayalsobepresentin concentrationscomparabletoCm-242level.
NomenclatureThefollowingnomenclaturetabledefinesthetermsusedinequationsforsourcetermcalculations:
R g=Leakagerateofanobleradiogasisotope(µCi/sec)R h=Leakagerateofahalogenradioisotope(µCi/sec)Y=Fissionyieldofaradioisotope(atoms/fission)=Decayconstantofaradioisotope(sec
-1)T=Fuelirradiationtime(sec)T=Decaytimefollowingleakagefromfuelrod(sec) m=Nobleradiogasdecayconstantexponent(dimension-less)n=Radiohalogendecayconstantexponent (dimensionless)
K g=Aconstantestablishingthelevelofnobleradiogasleakagefromfuel K h=Aconstantestablishingthelevelofradiohalogenleakagefromfuel C h=Concentrationofahalogenradioisotopeinreactor
(µCi/g)M=Massofwaterintheoperatingreactor(g)
RBSUSARRevision14 11.1-9September2001=Cleanupsystemremovalconstant(sec
-1)=Cleanupsystemflowrate(g/sec)
M(g)=Halogensteamcarryoverremovalconstant(sec
-1)Concentrationofhalogenradioisotopeinsteam(µCi/g)Steamflow=C h (µCi/g)(g/sec)
M(g)11.1.1.2ActivationProductsCoolantActivationProductsThecoolantactivationproductsarenotadequatelycorrelatedbysimpleequations.Designbasisconcentrationsinreactorwater andsteamhavebeenestimatedconservativelyfromexperience data.TheresultantconcentrationsarelistedinTable11.1-7.14Underconditionsofhydrogenwaterchemistryenhancedevolutionofnitrogentosteamisexperiencedinanon-linearfashionas reportedinEPRIReportTR-103515(Reference11.1-12).
Measurementdatafromhydrogenwaterchemistrytestsatvarious BWRplantssuggeststhatthedoserateincreaseisafunctionof feedwaterhydrogenconcentration,whichinturniscontrolledby thehydrogeninjectionrate.Theonsetofthenitrogen(N-16) activityincreaseusuallyoccursatafeedwaterhydrogen concentrationabove0.35ppm.Theriseofthemainsteam activityusuallyreachesaplateauataround1.5ppm.Forall BWRplantssurveyed,themaximumnormalizedmainsteamactivity increaseovernormalwaterchemistryconcentrationsconditionsis lessthanafactorofsix(6)withfeedwaterconcentrationsupto 2ppm.InTable11.1-7otherisotopesisnotcharacterized overwhelmingdominanceofnitrogenintheradiationsignatureof thesteam.Therefore,theconcentrationsoftheseisotopesare notassumedtobechangedinanysignificantmannerunder hydrogenwaterchemistry.Inaddition,thoughthewater concentrationsofnitrogenwilldecreasebyapproximately10-20%
underhydrogenwaterchemistry,thedecreaseisignoredforthe purposesofconservativelyboundingnormalandhydrogenwater chemistryoperatingconditions.
14NoncoolantActivationProductsTheactivationproductsformedbyactivationofimpuritiesinthe coolantorbycorrosionofirradiatedsystemmaterialsarenot adequatelycorrelatedbysimpleequations.Thedesignbasis sourcetermsofnoncoolantactivationproductshavebeenestimatedconservativelyfromexperiencedata (8).TheresultantconcentrationsarelistedinTable11.1-8.Carryoveroftheseisotopesfromthereactorwatertothesteamisestimatedtobe0.1percent(<0.001fraction).
RBSUSAR 11.1-9aAugust198711.1.1.3TritiumInaBWR,tritium,whichisavailableforreleaseinliquidandgaseouswastes,isproducedbythreeprincipalmethods.1.Activationofnaturallyoccurringdeuteriumintheprimarycoolant2.NuclearfissionofUO 2 fuel3.Neutroncapturereactionswithboronusedinreactivitycontrolrods.Thetritiumformedincontrolrods,whichmaybereleasedfroma BWRinliquidorgaseouseffluents,isbelievedtobe RBSUSARRevision14 11.1-9bSeptember2001THISPAGELEFTINTENTIONALLYBLANK RBSUSAR 11.1-10August1987negligible.Aprimesourceoftritiumisthatfromactivationofdeuteriumintheprimarycoolant.Asecondarysourceoftritium mayalsobetransferredfromfueltoprimarycoolant.The followingdiscussionislimitedtotheuncertaintiesassociated withestimatingtheamountsoftritiumgeneratedinaBWRwhich areavailableforrelease.Tritiumproducedbyactivationofdeuteriumintheprimarycoolantisavailableforreleaseinliquidorgaseouseffluents andcanbedeterminedbyusingtheequation:VR act=3.7x10 4 P Where: R act=Tritiumformationratebydeuteriumactivation(Ci/sec/MWt)=Macroscopicthermalneutroncrosssection(cm
-1)=Thermalneutronflux[neutrons/(cm 2)(sec)]V=Coolantvolumeincore(cm 3)=Tritiumradioactivedecayconstant(1.78x10-9 sec-1)P=Reactorpowerlevel(MWt)ForrecentBWRdesignsR actiscalculatedtobe:
(1.3+/-0.4)x10-4µCi/sec/MWt.Theuncertaintyindicatedisderivedfromtheestimatederrorsin selectingvaluesforthecoolantvolumeinthecore,coolant densityinthecore,abundanceofdeuteriuminlightwater(some additionaldeuteriumispresentbecauseoftheH(n,)Dreaction),thermalneutronflux,andmicroscopiccrosssectionfordeuterium.Thefractionoftritiumproducedbyfissionwhichmaytransferfromfueltothecoolantismuchmoredifficulttoestimate.
However,sincezircaloy-cladfuelrodsareusedinBWRs, essentiallyallfissionproducttritiumremainsinthefuel rods (4).
RBSUSARRevision1 7 11.1-11ThisisconfirmedbythestudymadeatDresdenUnit1in1968bytheU.S.PublicHealthService (5)(USPHS)whichsuggeststhatessentiallyallofthetritiumreleasedfromtheplantcouldbeaccountedforbythedeuteriumactivationsource.Forpurposes ofestimatingtheleakageoftritiumfromdefectivefuel,wecan maketheassumptionthatitleaksinamannersimilartothe leakageofnobleradiogases.Wecanthususetheempirical relationshipdescribedasthediffusionmixture,usedfor predictingthesourcetermofindividualnoblegasradioisotopes, asafunctionoftotalnoblegassourceterm.Theequationwhich describesthisrelationshipis:
R diff=KyWhere: R diff=Leakagerateoftheradioisotope(µCi/sec)y=Fissionyieldfraction=Radioactivedecayconstant(sec
-1)K=ConstantrelatedtototalleakagerateIfthetotalnobleradiogassourcetermis10 5µCi/secafter30-mindecay,wewouldcalculateleakagefromthefueltobeabout0.24µCi/secoftritium.ToplacethisvalueinperspectivewiththeUSPHSstudy,theobservedleakagerateofKr-85(whichhasahalf-lifesimilartothatoftritium)was0.06 to0.4timesthatcalculatedusingthediffusionmixture relationship.Thiswouldsuggestthattheactualtritiumleakageratemightrangefrom0.015to0.10
µCi/sec.SincetheannualaveragenobleradiogasleakagefromaBWRisexpectedtobelessthan0.1Ci/sec(t=30min),theannualaveragetritiumrelease ratefromthefissionsourcecanbeconservativelyestimatedat 0.12+/-0.12µCi/sec.14Fora30 9 1-MWtreactorthetotaltritiumappearancerateinreactorcoolantandreleaserateineffluentscanbeestimatedtobeabout17Ci/yr.
14Tritiumformedinthereactorisgenerallypresentastritiated oxide(HTO)andtoalesserdegreeastritiatedgas(HT).Tritiumconcentrationinthesteamformedinthereactoristhe sameasinthereactorwateratanygiventime.Thistritium
concentration is also present in RBSUSAR 11.1-12August1987condensateandfeedwater.Sinceradioactiveeffluentsgenerallyoriginatefromthereactorandpowercycleequipment,radioactive effluentsalsohavethistritiumconcentration.Condensate storagereceivestreatedwaterfromtheradioactivewastesystem andrejectswatertothecondensatesystem.Thus,allplant processwaterhasacommontritiumconcentration.OffgasesreleasedfromtheplantcontaintritiumwhichispresentasHTresultingfromreactorwaterradiolysis.In addition,watervaporpresentinventilationairduetoprocess steamleaksorevaporationfromsumps,tanks,andspillson floorsalsocontainstritium.Theremainderoftritiumleaves theplantinliquideffluents.Recombinationofradiolysisgasesintheairejectoroffgassystemformswatervaporwhichiscondensedandreturnedtothe maincondenser.Thisreducestheamountoftritiumleavingin gaseouseffluentsandresultinaslightlyhighertritium concentrationintheplantprocesswater.Reducingtheamountof liquideffluentdischargedalsoresultsinahigherprocess coolantequilibriumtritiumconcentration.Essentiallyalltritiumenteringtheprimarycoolantiseventuallyreleasedtotheenvirons,eitheraswatervaporand gastotheatmosphere,orasliquideffluenttotheplant discharge.Reductionduetoradioactivedecayisnegligibledue tothe12-yrhalf-lifeoftritium.TheUSPHSstudyatDresdenUnit1estimatedthatapproximately90percentofthetritiumreleasewasobservedinliquideffluentwiththeremaining10percentleavingasgaseouseffluent (5).Efforttoreducethevolumeofliquideffluentdischargesmaychangethisdistribution;however,fromapracticalstandpoint, thefractionoftritiumleavingasliquideffluentmayvary between60and90percentwiththeremainderleavingingaseous
effluent.11.1.2FuelFissionProductInventoryandFuelExperience 11.1.2.1FuelFissionProductInventory Fuelrodandfuelplenumradioisotopicinventory,alongwithescaperatecoefficientsandreleasefractions,arenotusedin establishingBWRdesignbasissourcetermcoolantactivities.
Fuelfissionproductinventoryinformationisusedin establishingfissionproductsourcetermsforaccidentanalysis andisthereforediscussedinChapter15.
RBSUSAR 11.1-13August198711.1.2.2FuelExperienceAdiscussionoffuelexperiencegainedforBWRfuel,includingfailureexperience,burnupexperience,andthermalconditions underwhichtheexperiencewasgained,isavailablein References2,3,and6.11.1.3ProcessLeakageSources Processleakageresultsinpotentialreleasepathsfornoblegasesandothervolatilefissionproductsviaventilation systems.Liquidfromprocessleaksareallcollectedandrouted totheliquid-solidradwastesystem.Radionuclidereleasesvia ventilationpathsareatextremelylowlevelsandhavebeen insignificantcomparedtoprocessoffgasfromoperatingBWR plants.However,becausetheimplementationofimprovedprocess offgastreatmentsystemsmakestheventilationrelease comparativelysignificant,GEhasconductedmeasurementsto identifyandqualifytheselow-levelreleasepaths.GEhas maintainedanawarenessofothermeasurementsbytheElectric PowerResearchInstituteandotherorganizationsandroutine measurementsbyutilitieswithoperatingBWRs.Leakageoffluids fromtheprocesssystemresultsinthereleaseofradionuclides intoplantbuildings.Ingeneral,thenobleradiogasesremain airborneandarereleasedtotheatmospherewithlittledelayvia thebuildingventilationexhaustducts.Theradionuclides partitionbetweenairandwater,andairborneradioiodinesmay "plateout"onmetalsurfaces,concrete,andpaint.Asignificant amountofradioiodineremainsintheairorisdesorbedfrom surfaces.Radioiodinesarefoundinventilationairasmethyl andinorganiciodineswhichareheredefinedasparticulate, elemental,andhypoiodousacidformsofiodine.Particulatesare alsopresentintheventilationexhaustair.TheairborneradiologicalreleasesfromBWRbuildingheating,ventilating,andairconditioningandthemaincondenser mechanicalvacuumpumphavebeencompiledandevaluatedin NEDO-21159,AirborneReleasesfromBWRsforEnvironmentalImpactEvaluations,March1976,LicensingTopicalReport (7).Thisreportisperiodicallyupdatedtoincorporatethemostrecentdataonairborneemissions.Theresultsoftheseevaluationsarebased ondataobtainedbyutilitypersonnelandspecialin-plant studiesofoperatingBWRplantsbyindependentorganizationsand GE.TheresultsaresummarizedinSection12.2.
RBSUSAR 11.1-14August198711.1.4RadioactiveSourcesintheLiquidRadwasteSystemTheradioactivesourcesfortheliquidradwastesystemaredescribedinSection11.2.11.1.5RadioactiveSourcesintheOffGasSystem TheradioactivesourcesfortheoffgassystemaredescribedinSection11.3.11.1.6RadioactiveSourcesforComponentFailures Theradioactivesourcesconsideredforevaluatingtheradiologicalconsequencesofcomponentfailuresaredescribedin Section15.7.
RBSUSARRevision14 11.1-15September2001References-11.11.Brutschy,F.J.AComparisionofFissionProductReleaseStudiesinLoopsandVBWR.PresentedatTripartiteConferenceonTransportofMaterialsinWaterSystems, ChalkRiver,Canada,February1961.2.Williamson,H.E.andDitmore,D.C.ExperiencewithBWRFuelThroughSeptember1971,NEDO-10505,May1972(Update).3.Elkins,R.B.ExperiencewithBWRFuelThroughSeptember1974,NEDO-20922,June1975.
- 4. Ray,J.W.TritiuminPowerReactors.Reactorand Fuel-ProcessingTechnology,12(1),p.19-26,Winter
1968-1969.5.Kahn,B.,etal.RadiologicalSurveillanceStudiesataBoilingWaterNuclearPowerReactor,BRH/DER70-1,March
1970.5. Williamson,H.E.andDitmore,D.C.CurrentStateofKnowledgeofHighPerformanceBWRZircaloyCladU0 2 Fuel,NEDO-10173,May1970.7.Marrero,T.R.AirborneReleasesFromBWRsforEnvironmentalImpactEvaluations,NEDO-21159,March1976.8.Elkins,R.B.ExperiencewithBWRFuelThroughDecember1976,NEDO-21660,July1977.9.Skarpelos,J.M.andGilbert,R.S.TechnicalDerivationofBWR1971DesignBasisRadioactiveMaterialSourceTerms,NEDO-10871,March1975.
- 10. NUREG-0016,Revision1.CalculationofReleasesofRadioactiveMaterialsinGaseousandLiquidEffluentsfrom BoilingWaterReactors(BWRs).14 11. Lin,C.C.,ChemistryBehaviorofRadioiodineinBoiling WaterReactorSystemsII:EffectsofHydrogenWater Chemistry,NuclearTechnology,Volume97,January1992.
- 12. EPRITR-103515-R1,BWRWaterChemistryGuidelines-1996Revision,December1996.
14 RBSUSARRevision10 11.2-1April199811.2LIQUIDWASTEMANAGEMENTSYSTEM11.2.1DesignBases 11.2.1.1PowerGenerationDesignBases10Theobjectiveoftheradioactiveliquidwaste(radwaste)systemistocollect,monitor,andprocessforreuseordisposalall potentiallyradioactiveliquidwastesinacontrolledmannerso thattheoperationoravailabilityisnotlimited.Theliquid wastesubsystemsaregroupedasequipmentandfloordrains, regenerativewasteandphaseseparator/backwashtank.Thesystem providesformaximumrecycleofwatertothecondensatestorage tanks.Sufficienttreatmentanddiversityoftypesofequipment isavailabletoprocessnormalplantwastetocondensatequality.
Dischargeofprocessedliquidwasteswillonlybenecessaryto ensuretheradwastesystemoperabilitytosupportplantoperating conditionsortocontroltritiumbuildupinthecondensate storagetank.Dischargeofprocessedliquidwastetothe environsisviathecoolingtowerblowdownline.Maximumrecycle ofwastewaterresultsinaradwastematerialreleasewhich conformstothe"aslowasreasonablyachievable"(ALARA) requirementsof10CFR50,AppendixI.
10Theradioactiveliquidwastesystemhasthecapacityandcapabilityofprocessingtheanticipatedquantitiesand activitiesofliquidwastesresultingfromnormaloperation.Thesystemincludestheproperselectionofequipmentandinstrumentationtoensurethattheradioactivityconcentrations resultingfromliquiddischargesfromtheplantarewithinthe limitssetforthin10CFR20.RefertoAppendix11Afordiscussionoftheliquidradwastesystemconformancetothedesignobjectivesof10CFR50, AppendixI.11.2.1.2SystemDesignBases Theliquidradwastesystemisdesignedtomaintainsafeoperatingconditionsbyminimizingradiationhazardstoplantpersonnelby applyingmeaningfuldesigntechniquestoeachsubsystem.The systemcollects,processes,stores,monitors,anddisposesofall liquidradioactivewastesreceivedfromthereactorcoolant systemorliquidswhicharepotentiallycontaminateddueto contactwithliquidsfromthereactorcoolantsystem.Equipment isselected,arranged,andshieldedtopermitoperation, inspection,andmaintenancewithpersonnelradiationexposureas lowasreasonablyachievableandwithinthelimitsasdelineated in10CFR20.
RBSUSARRevision8 11.2-2August1996Equipmentisselectedrequiringminimummaintenance.Sumps,pumps,valves,andinstrumentsarelocatedinaccessibleareas.
Tanksandprocessingequipmentwhichmaycontainsignificant quantitiesofradioactivityaretothegreatestextentpossible appropriatelyshieldedfromeachotherandfrompersonnelaccess areasandcontrolsorequipmentrequiringregularmaintenance.
Air-operatedvalvesconveyinghighlyradioactivefluidsare locatedinshieldedcompartmentsandareprovidedwith rack-mountedsolenoidoperatorsoutsidethehighradiation
fields.3Insomecasesseveralstoragetanksarelocatedinacommon shieldedarea.Sinceallregularlymaintainedequipment(pumps, valves,etc.)associatedwiththesetanksislocatedoutsidethe shieldinginaccessibleareas,noregularmaintenanceis anticipatedwithintheshieldedtankcompartments.Inallcases, excesstankcapacityisprovidedfornormaloperation.Ifan operationalproblemoccurswithinacompartment,thetankcanbe isolatedwithoutlossofunitoperatingcapability.Theliquid radwastesystemisdividedintosubsystemsthatcombinevarious sourcesofliquidwasteswithsimilarconductivityandisotopic concentrationsforappropriateprocessing.Majorflowpaths, equipment,leakageanddrainliquidsareindicatedin Fig.11.2-1athrough11.2-1k.
3Selectionoftheequipment'stypeandsizefortheradwastefacilityattheRiverBendStationwasdoneonthebasisofboth previousoperatingexperienceanddemonstratedreliabilityin otherindustrialapplications.Table11.2-1liststheequipment designdataoftheliquidradwastefacility.Surgecapacityin tankageisprovidedtocovercontingenciessuchasprocessing equipmentoutages,orabnormalevolutionsresultinginthe productionofexcessivewastevolumes.Tankvolumeprovidedis inexcessofthatrequiredwithwasteinputsintotheliquid radwastesystembasedonNUREG-0016,Rev.1,Table1-4.Surges canbeaccommodatedbyextendedoperation.Thisisdescribedin detailinSection11.2.2.Laundrymaybeprocessedintwodifferentways.Itcanbeeitherwetwashedordrycleaned,onoroffsite.11.2.1.2.1ApplicableCodesandStandardsTable11.2-2liststheapplicablecodesandstandardsforequipmentintheliquidradwastesystems.ThebasisforSafety ClassNNSandthematerialselectionsforequipmentintheliquid radwastesystemsisthecriteriaasestablishedbyRegulatory Guide1.143,asdiscussedinSection11.2.1.3.2.
RBSUSARRevision10 11.2-3April1998Theatmosphericstoragetanksarefilamentwoundfiberglassreinforcedplastictanks.Theyaredesignedtomeetorexceed NationalBureauofStandardsVoluntaryProductStandardPS15-69 andtheAmericanSocietyforTestingandMaterialsSpecification No.ASTMD3299-74.11.2.1.2.2StructuralDesign8TheradwasteequipmentarrangementispresentedinFig.1.2-29through1.2-32andisdescribedinSection3.8.4.1.8.In accordancewithRegulatoryGuide1.143andBranchTechnical PositionETSB11-1(Revision1,4/75),thebuildingis seismicallyanalyzedasdescribedinSection3.7.2.16A.The radwastebuildinglayoutprovidesdesignfeaturesconsistentwith maintainingpersonnelexposureALARA.
810Thecompartmentcontainingthewastecollectorsand,thefloordraincollectortanks,andtheregenerativewastetanksis watertighttoanelevationabovethatresultantfroma catastrophicfailureofalltankswithinthecompartment.This isaccomplishedbyprovidingwatertightsleevesforallpiping penetratingthecompartmentwallsandrestrictingpersonnel accessestolevelsabovetheresultantelevationidentified
previously.
1011.2.1.3CompliancewithDesignCriteriaandStandards11.2.1.3.1GeneralDesignCriteria(GDC)
ControlandmonitoringofradioactiveliquidreleasesinaccordancewiththerequirementsofGDC60isdescribedin Section11.2.2.5.Liquidwasteholdupcapacity,andthebasis therefor,isdescribedinSection11.2.2.MonitoringofeffluentdischargedfromtheliquidradwastesystemisdescribedinSection11.2.2.6.Theprocessandeffluent radiationmonitoringsystemsaredescribedinSection11.5.11.2.1.3.2RegulatoryGuides RegulatoryGuide1.143identifiesthequalitylevel,qualitygroupclassification(safetyclass),seismicrequirements,and materialrequirementsforequipmentandstructurescontaining radioactivewaste.Theliquidradwastesystemisinconformance withtheguideinthat:
RBS USAR Revision 24 11.2-4 1. The equipment within the system is designed in accordance with requirements identified in Table 1 of the guide.
- 2. Materials for pressure-retaining components conform to the requirements of the specification for materials in Section II of the ASME Code, except that nickel alloy steel, fiberglass-reinforced plastic (FRP) piping, High Density Polyethylene (HDPE) piping and polypropylene-lined (PPL) steel piping are used. The use of FRP piping is restricted to condensate flush connections to liquid radwaste piping and components. HDPE piping is only used to handle condensate quality water that is being discharged. PPL piping is used in the demineralizer systems because of its
improved corrosion resistance.
- 3. Foundations and walls of the radwaste building, to an elevation above that sufficient to contain the maximum
liquid inventory expected in the building, are designed to the seismic criteria described in the guide. This is
described in detail in Section 3.8. 3 4. Tanks are provided with means to monitor and alarm abnormal liquid levels. The condensate storage tank, which is located outside, is provided with an overflow piped to a
sump. The sump is provided with two pumps which discharge
to the radwaste system. An analysis has shown (Section 15.7.3.2) that the dose consequences to surrounding
or downriver population associated with a tank failure are
negligible. Therefore, the condensate storage tank is not
provided with dikes.
3 5. Indoor tanks are in compartments or areas provided with intermediate sumps designed for the handling of radioactive wastes and for having provision for discharge of the wastes
to the liquid radwaste system.
11.2.1.3.3 NUREGs
NUREG-0016, Rev. 1, provides guidance in calculational methods
associated with liquid radwaste systems. The liquid radioactive waste tankage provided is in excess of that required based on twice the single unit daily expected average input flows (Table 1-4, p 1-11 of NUREG-0016, Rev. 1). Equipment decontamination factors (DFs) used in analysis are consistent with Table 1-5 of the NUREG.
11.2.2 System Description 3 The liquid radwaste system consists of one major subsystem plus one minor subsystem as shown in Fig. 11.2-1a through 11.2-1k. A
simplified flow diagram of the liquid radwaste system is shown in Fig. 11.2-2. The collection tanks, process equipment, and sample
tank systems are located in the radwaste building.
3 RBSUSARRevision11 11.2-5October1998OverallmaterialandactivitybalancesfortheradwastesystemarelistedinTable11.2-3andthederivationbasesareprovided inSection11.2.2.6.Theisotopicconcentrationsforreleaseto theenvironsaregiveninTables11.2-4and11.2-5.All equipmentandsystemshavebeendesignedtoprocessthemaximum anticipatedwastevolumewithina24-hrperiod.10Over172,400galofusablestoragecapacityisavailableto collectandstoretheaveragepeakliquidradwasteinfluent volumesofapproximately40,280gpd,within-processinventoryat approximately10,000gal.Thedailyaverageradwastesystem inleakagemayvarybyasmuchas7200gpdwhencomparingthe summermonthstowintermonths.Thisisduetothevarious buildingunitcoolersremovingcondensationfromtheatmosphere.
Radwastetotalsysteminleakageaveragedoveranentireyearis expectedtobeapproximately36,680gpdwithalowaverageof 33,080gpdandhighaverageof40,280gpd.Storagefacilities arealsoavailabletoreceivethetreatedliquids.Thetreated liquidbulkstoragecapacityis68,800gal.Thetreatedliquid isdischargedtotheenvironmentwhennecessarytoensurethe radwastesystemoperabilitytosupportplantoperatingconditions andtocontroltritiumbuildupinthecondensatestoragetankto keepoffsitereleasesaslowasreasonablyachievable,andto controltotalplantwaterinventorywhennecessary.3Briefly,thewasteandfloordraincollectorsubsystemconsists ofthewaste,regenerantandfloordraincollectortankswhich receiveandstorethefeedtothesubsystem;theradwastefilter whichremovesinsolubleparticles;aradwastetreatmenttrain whichremovesthesolubleandcolloidalionicmaterial,andthe recoverysampletankswhichholdtheprocessedwaterfortesting beforeitisreturnedtothecondensatesystem,dischargedtothe coolingtowerblowdown,ortransferredbacktothewaste collectortankinletheaderforreprocessing.111Inadditiontotheprocessingsubsystem,asupplementarysystem isincludedintheliquidradwastefacility.Thisisthephase separator/backwashtanksystemwhichprovidesstorageandholdup offiltersludgesandspentresinsfromthereactorwatercleanup filter/demineralizers,thecondensatepolishers,theradwaste treatmentvessels,thefuelpooldemineralizers,andtheradwaste filters.Followingaperiodwhichallowsforsufficientdecayof theradionuclidesandsettlingofsolids,thecontentsofthe phaseseparator/backwashtanksmaybetransferreddirectlytoa solidwastesystemortoawastesludgetankforprocessingand thendisposalinthesolidwastesystem(refertoSection11.4).
111310 RBSUSARRevision10 11.2-6April1998Allliquidradwasteequipmentislocatedintheradwastebuilding.Majorequipmentincludedintheliquidradwastesystem islistedbelow(seeTable11.2-1forequipmentdesign
parameters):
- 2. WasteandFloorDrainCollectorSubsystema.Fourwastecollectortanksandtwopumpsb.Threefloordraincollectortanks,twopumps,andoneplate-typeoilseparatorc.Tworadwastefilters10d.Twotrainsofradwaste e.Fourrecoverysampletanksandthreepumps3f.Twochemicalregeneranttanks/chemicalwastetanksandonepump.
1032. PhaseSeparator/BackwashTankSubsystema.Twophaseseparatortanksandtwopumps b.Onebackwashtankandtwopumps11.2.2.1Summary103TheinputwastestreamstothevarioussubsystemsoftheliquidradwastesystemareidentifiedonFig.11.2-1athrough11.2-1k.
AverageflowratesarepresentedinTable11.2-3fortheprimary flowstreamsshowninthesefigures.Acompositesummaryof expectedanddesignvaluesforthewastestreamreleasetothe environmentisgiveninTables11.2-4and11.2-5,respectively.
10311.2.2.2WasteandFloorDrainCollectorSubsystem3Relativelylowconductivity(lessthan50S/cm)andvariableactivitylevelwastesarestoredinthewastecollectortanks.
Thetankinfluentsincludelowconductivitydrainsfrompiping andequipmentthatcannotbereturneddirectlytothecondenser hotwell,wastesfromthereactorcoolant,condensateand feedwatersystems,andotherassociatedauxiliaries.Influents tothetanksalsoincludedecantedliquidsfromthephase separatortanks,condensatedemineralizersresinrinsewater, condensatestoragetankoverflow,decontaminationandchemistry laboratorydrainandultrasonicresincleanerwastes.
3 RBS USAR Revision 18 11.2-7 103 Radioactive materials are removed from the input wastes by filtration (insolubles and organic removal) and ion exchange (soluble and colloidal removal). Radwaste treatment train effluent is then routed to the recovery sample tanks for transfer to the condensate storage tank, the waste
collector tank inlet header for reprocessing through the radwaste treatment
train, or the cooling tower blowdown line for discharge. Prior to discharge into the cooling tower blowdown line, this waste is checked for activity by a radiation monitor. Liquids with radioactivity levels exceeding specified limits or with unacceptable chemistry may be recycled back to the waste collector tanks for further processing. The radwaste deep bed filters are provided for removal of insolubles. Two identical, cross connecting filters are provided so that maintenance may be performed on one filter or a failure of one would not inhibit daily liquid radwaste
processing.
3The radwaste treatment train includes a three pressure (treatment) vessels with effluent retention elements in series. Depleted treatment media is flushed out of the pressure vessel with air and water and directed, via the phase separator/backwash tank subsystem (Section 11.2.2.5), to the radioactive solid waste system (Section 11.4). Four waste collector tanks are provided with a total capacity of 90,520 gallons. This volume is significantly in excess of that required to accommodate 1 day's influent to the waste and floor drain collector subsystem. However, should operational requirements dictate, the influent can be diverted to the floor drain
collector tanks. 3Mobile, portable filter/demineralizers may be used whenever necessary for special applications or temporary replacement of an installed process
train. Space is available for these portable filter/demineralizers in a spare cubicle, on elevation 117 ft of the radwaste building, provided with
curbs, floor drains, and 2-ft thick concrete walls. Valved piping connections are provided in the cubicle for bypassing the filter only, the demineralizer only, or the entire filter/demineralizer train. This
arrangement meets the intent of Regulatory Guide 1.143. Additional connections and interfaces with the radwaste system, drain system, service air system, condensate demineralizer system, and 480 VAC power are provided to support a vendor-supplied filtration system to supplement installed process trains. An area for vendor skid-mounted equipment is provided on 65 elevation of the Radwaste Building. The area is bermed to contain any spills and radiation shielding is provided where necessary.Process rates may be varied depending upon the desired results of processing (e.g. treatment of impurities or increased processed water
volume). Maximum train flow can be expected to be 100 gpm. 11Potentially high conductivity liquid wastes (50 umho/cm and greater) from the radwaste building sumps, reactor building floor drain sumps, auxiliary building floor drain sump, fuel building floor drain sumps, turbine building floor drain sumps, and shop floor drain sumps are collected in the floor drain collector tanks. Influent to the tanks also includes the waste
solidification/dewatering stream. The liquid waste is treated as necessary using either filter with either process train and then recovered, discharged, or returned to the waste collectors subsystem for reprocessing.
Section 11.2.2.6 gives the disposition guide for control of waste activity
movement.3 10 11 RBS USAR Revision 16 11.2-8 March 2003 Three floor drain collector tanks are provided with a total capacity of 64,800 gallons. This volume is significantly in excess of that required to accommodate 1 day's influent to the waste and floor drain subsystem. However, should operational requirements dictate, the influent can be diverted to the waste collector tanks. 10The floor drain collector stream can be processed through the radwaste filter(s) and treatment trains at varied rates depending on
media selection and desired results. Maximum train flow can be
expected to be 100 gpm. 11.2.2.3 Phase Separator/Backwash Tank Subsystem 16Filter sludges, slurries, and spent resins are collected, decanted, and conveyed to the radioactive solid waste system (Section 11.4) by the phase separator/backwash tank subsystem. The phase separator tank influents include filter sludges (powdered resin and crud) produced during the operation of the reactor water cleanup system filter/demineralizers. The backwash tank influent, discussed below, can also be diverted to either of the phase separator tanks and to
the waste sludge tank.
163Normally one phase separator tank is in service and one is isolated to permit the short-lived isotopes to decay prior to processing through the radioactive solid waste system. Sufficient time exists between influent batches entering the inservice phase separator for the batch to settle and the decant to be drawn off. The phase separation tank pump transfers the liquid phase to the waste collector subsystem, and the concentrated sludge and expended resin
is pumped directly to the radioactive solid waste system. The backwash tank accepts filter backwashes from the waste collector and floor drain influent strainers and filters, the spent fuel pool and suppression pool cleanup filters, spent resins from the condensate, radwaste, suppression pool cleanup and fuel pool treatment vessels. These influents can be diverted from the
backwash tank to either of the phase separator tanks via three-way valves in the backwash tank inlet header. Operation of the backwash tank is similar to the phase separator tanks in that solids are
allowed to settle between influent batches to the tank and the decant transferred to the floor drain and waste collector subsystem.
The concentrated sludge and expended media is sent directly to the
radioactive solid waste system for processing.
3 1011.2.2.4 System Operational Analysis The flow rate and the activity concentrations (fractions of primary coolant activity) shown in Table 11.2-3 were developed using a
material balance calculation and data from NUREG-0016, Rev. 1.
RBSUSARRevision10 11.2-9April199810Decontaminationfactors(DFs)oftheprocessingunitscanbeexpectedtobeasfollows(dependingonthetreatmentmedia
selected):
Equipment DF RemarksRadwastemediafilter1Forcorrosion/activationproducts(insolubles)Radwastetreatmentvessels 1.Wastecollectorstream100/1,000DFforCs,Y,Nb,Zr/DFforotherisotopes (solubles) 2.Floordraincollector
streamDFforCs,Y,Nb,Zr/
DFforotherisotopes (solubles) 1011.2.2.5InstrumentationandControl3Thepurposeoftheinstrumentationandcontrolsystemisto provideindicationsofprocessoperation,equipmentperformance systemstatus,andprovidecentralcontrolofprocessequipment.
Theradwastecontrolpanelislocatedintheauxiliarycontrol
room.3Instrumentationforthedifferentsubsystemsisdescribedseparatelyinthefollowingsections.108Inmultipletanksubsystems,e.g.,floordraincollector, recoverysample,regenerativewasteandphaseseparatortanks, theinletvalvesforeachtanksystemwiththeexceptionofthe wastecollectiontanksareinterlockedsuchthatatleastone valvemustbeopenatalltimes.Forthewastecollectiontanks, administrativecontrolsarerelieduponinlieuofaninterlock.
Thisensuresthatatleastoneofeachtypeoftankisavailable toacceptinfluents.
10811.2.2.5.1WasteandFloorDrainCollectorSubsystemControlswitchesareprovidedontheradwastecontrolpanelformanualoperation/automaticshutdownofthewasteandfloordrain collectortankpumps.Thetanklevelsareindicatedand annunciatedontheradwastecontrolpanel.Sincetwowaste collectorpumpsareprovidedforfourtanks,andtwofloordrain collectorpumpsareprovidedforthreetanks,automaticshutdown oftheoperatingpumpisobtainedbyinterlockingthelowtank levelswitchwiththetankoutletvalvepositionandthepump suctionvalveposition,suchthateitherpumpcanbeshutdownby anytanklowlevelbytheoperatorestablishingasuctionflow path.Pumphighorlowdischargepressureconditionsare annunciatedonthecontrolpanel.
RBS USAR Revision 21 11.2-10Control switches are provided for either manual or automatic operation of the pump discharge air-operated valves.1063 An automatic backflushable duplex strainer assembly is provided immediately upstream of the radwaste filter. This strainer may be backflushed when a
predetermined differential pressure is attained.
Strainer internals may be removed under administrative controls.
A polyelectrolyte (cationicpolymer) which tends to agglomerate suspended solids is provided to
maximize filter performance. Polyelectrolyte injection into the filter
influent can be set manually or operated in automatic. Excessive turbidity
or total organic carbon (suspended or dissolved oil) in the filter effluent can result in the effluent being recycled back to the waste collector tanks. A filter flow rate of 100 gpm can be maintained over the range of filter differential pressures by the use of a flow controller. Filter backwash can be automatically initiated by a high differential pressure
across the filter vessel when the filter is operated in the automatic mode.
When operated manually, the filter may be backwashed manually or automatically when the differential pressure across the filter is observed
to be high.
6Conductivity, flow, pressure, and differential pressure indication may beused to allow evaluation of media performance. The treatment vessel effluents are monitored and/or tested for depletion of the treatment media
selected.The recovery sample tanks are provided with high and low level alarms; thehigh alarm gives the operator time to make an empty tank available for receiving influent, and the low level alarm shuts down the operating
discharge pump. The pumps are operated on a remote manual basis. Pump discharge pressures are indicated on the radwaste control panel. The recovery sample tank contents can be transferred to the condensate storage
tanks; however, should it become necessary, the water can be reprocessed or
discharged via the cooling tower blowdown line, under strict administrative
controls.3A control switch is provided for manual operation of the recovery sampletank discharge valve to the cooling tower blowdown line. Interlocks
prevent the valve from being opened if a high radiation level is present.A control switch is provided for either manual or automatic operation of the recovery sample tank discharge diverting valve. In the automatic mode, the valve is opened when a high radiation level is sensed, diverting the
recovery sample tank contents back to the waste collector tank.3The recovery sample tank discharge flow rate to the cooling tower blowdown
is maintained at its set point by a flow control valve operated from the
radwaste control panel. During liquid releases the flow rate and temperature are continuously recorded. The activity level information is
maintained by the radiation monitor.
310 RBSUSARRevision10 11.2-11April1998 311.2.2.5.2PhaseSeparator/BackwashTankSubsystemEachphaseseparatortankhaslevelswitchesasfollows:
Fourpumpsuctionpathsareavailablepertank,theupperandlowerdecantconnectionsandthetankoutletconnection.The bubbler-typetankleveltransmitterhasswitchesassociatedwith eachtankconnection.Pumpoperationisinterlockedsuchthata suctionflowpathmustbeestablishedandthetanklevelmustbe abovethatsuctionpointpriortoestablishingapumpstart permissive.Afourthsuctionpath,aflushconnectionforthe pumpsuctionpiping,isalsoprovided.Thisissimilarly interlockedsuchthattheopensuctionflushvalveresultsina startpermissive.Sincetwo-phaseseparatorpumpsareprovided forthetwotanks,automaticshutdownisobtainedinasimilar mannertothatusedfortheothertank/pumpsubsystems.Anofflineturbidityanalyzerislocatedinthepumpcommondischargeheader.Thisanalyzerisprovidedtoensurethatthe turbidityofthedecantfromthetanksisacceptablefortransfer tothewastecollectortanks.Ifunacceptable,analarmwarns theoperatortoeitherterminatethetransferordivertto anotherflowpath.103Thephaseseparatortanksludgeandexpendedresincanbesentto eitherthewastesludgetankordirectlytoalinerfor
reprocessing.
3Thebackwashtankhaslevelswitchessimilartothoseprovidedforthephaseseparatortank,i.e.,forthetwodecant connectionsandthetankoutletconnection.Similarly,thepump suctionflushvalvesareinterlockedwiththepumps.Twopumps areprovidedforthebackwashtankwiththeoperatingpumpshut downautomaticallybytanklevel.Anofflineturbidityanalyzerislocatedinthepumpcommonrecirculationline.Thisanalyzerisprovidedtoensurethattheturbidityofthewaterfromthebackwashtank,ifdecanted,isacceptablefortransfertothefloordraincollectortanks.If unacceptable,analarmwarnstheoperatortoeitherterminatethe transferordiverttoanotherflowpath.Thebackwashtanksludgeandexpendedmediaishandledinamannersimilartothatforthephaseseparator.Normally, however,theentirecontentsofthebackwashtankaretransferred directlytotheradioactivesolidwastesystem.11.2.2.5.3PowerSourcesInstrumentsarepoweredfromthe120-Vinstrumentbusandreceiveoperatingairfromthe100psiginstrumentairsystem.
10Motorsandcontrolcircuitsarepoweredfromnormal480-Vac supplies.
RBS USAR Revision 18 11.2-12 11.2.2.6 Operating Procedures 10The operating procedures used for all liquid radwaste equipment are based on batch processing through the radwaste systems. This type of operation allows a time to sample and check the feed and effluent streams before and after each process step to prevent the inadvertent discharge of waste
having a radioactivity level above the control limit. 3The filters in the waste and floor drain processing subsystem are designed for operation at 100 gpm maximum. When the pressure drop across
the filter reaches a preselected level, the flow is discontinued. The
filter is then backwashed to the backwash tank. During filter
maintenance, the other filter can be used with either process train.
3The radwaste process trains are operated at varied rates depending on the desired processing results. Maximum process flow can be expected to be
100 gpm. There are three demineralizers in series composed of a cation, an anion, and a mixed bed unit. The feed is the effluent from the
radwaste filter. Each process vessel is monitored for pressure drop across the bed, conductivity of the effluent, and other key chemistry
parameters dependent upon treatment media selection. Media is selected to maximize recycle of water back to the Condensate Storage Tank and minimize offsite dose (ALARA) should a discharge of radioactive liquid water be necessary. Media is also evaluated in system compatibility.
This will ensure expected corrosion rates are essentially unchanged and system integrity is maintained. When one or more of the key chemistry
parameters is exceeded, flow is stopped and the treatment media is
replaced. This ensures maximum recycle of water to the Condensate Storage Tank as well as minimizes the dose to the general public (ALARA).
Section 11.2.2.2 contains discussion s o n the use of a portable filter/demineralizer system when necessary for special applications or
temporary replacement of an installed process train and available capability for utilizing an ultra-filtration system to supplement the current process
.Normally, all purified liquid from the waste collector tanks is sampled in the recovery sample tank and returned to the condensate system via the condensate storage tank. Periodically, purified water from the waste collector tanks is returned to its sub-system for reprocessing. On rare
occasions, this purified water source is discharged to the environment. 8No waste is discharged to the environment from the recovery sample tanks until the requirements of the Technical Requirements, 10CFR20 (for radionuclides other than dissolved and entrained noble gases), and the site NPDES permit are met. This ensures that only water of acceptable
quality is discharged from the plant.
8Liquid radwaste streams are combined to make the most effective use of the processing equipment available and to minimize the number of
processing cycles received by an individual waste batch prior to final disposition. It is intended that recycling of treated water within the
system is used as a tool to minimize radioactive liquid waste discharges.
10 RBSUSARRevision8 11.2-13August1996Condensateisusedasflushingagentwhenrequired;theuseofdemineralizedmakeupwaterisheldtoaminimumandclosely
controlled.108Theproceduralapproachtomonitorandcontrolliquidwaste effluentsiscontainedinSection11.5.Liquidwasteisreleased intothecoolingtowerblowdownlinefromtherecoverysample tanksonabatchbasis.Eachbatchisanalyzedpriortorelease forprinciplegammaemitters.Theresultantisotopicanalysisis usedtodeterminethebatchdischargeflowrateandDRMS radioactiveliquideffluentmonitoralertandalarmsetpoints.
Theseactionsensurethattheradionuclideactivitiesreleasedto theenvironmentaremaintainedbelowtheeffluentconcentration limit(ECL)specifiedin10CFR20.Detailedadministrative recordsaremaintainedforallradioactiveliquidreleases(e.g.,
totalactivity,temperature,flowrate,etc).Table11.2-5shows thatthedesignradioactivityconcentrationsindischargedliquid wastesaresignificantlybelowtheeffluentconcentrationlimit specifiedin10CFR20.
108Inadvertentdischargesofradioactiveliquidwastesareavoided by:1.Theimpositionofadministrativecontroltodeterminethemosteffectivemeansofprocessinganygivenbatch32.Automaticcontrols,indicatorlights,andalarmsattheauxiliarycontrolroomsituatedadjacenttothe radioactivewastebuilding 33.Batchprocessingcontrolsandprocedurestoensurethatknownquantitiesofactivityanddissolvedsolidsaremovedinacontrolledmannerwithinthesystem4.Adequatesizingoftanksandprocessingequipment,sothatanormalbatchcollectedoveraperiodofonedaymaybeprocessedwhileanotherisbeingreceived.Aradiationmonitorinthewastedischargepipeprovidesahigh radioactivityalarmandadischargevalvetripsignal.The radiationmonitorislocatedfarenoughupstreamofthedischarge valvetoensurevalveclosurepriortothereleaseofradioactive liquids.Liquidswithradioactivityexceedingtheradiation monitorsetpointarerecycledbacktotheradwastesystemfor furtherprocessing.Strictadministrativecontrolsareimposed onthetripsetpointofthedischargelineradiationmonitor.
Sampling,monitoring,andanalysisofthedischargetunnelwater inaccordancewithSection11.5areusedtohelpverifythe readjustmentofthesetpoint.
RBSUSARRevision9 11.2-14November199711.2.2.7PerformanceTestsTestsfortheremovalofinsolublesbyfiltrationandthereductionofconductivitybydemineralizationareconductedona periodicbasis.Theradioactivityoftheinputandoutput streamsofeachradwastetrainischeckedperiodically.Overallsystemtestsforthewasteandfloordraincollectorsubsystemarerunfortheactivityreductionfactor.11.2.3RadioactiveReleasesandDoses Table11.2-4isatabulationoftheexpectedannualactivityreleasedandconformswiththemethodandparametersgivenin NUREG-0016,Rev.1.Thedesignbasereleasefromtheliquid effluentstreaminCi/yrpernuclideisgiveninTable11.2-5and correspondstooperationwithdesignfailedfuelconditionsas discussedinSection11.1.Tritiumreleaseisanticipatedat45.6Ci/yr.
11.2.3.1ReleasePoints AllliquideffluentreleasesfromRiverBendStationaredischargedintothecoolingtowerwaterblowdownwhichis directedtotheMississippiRiver.Fig.11.2-1athrough11.2-1f showthesystemrelationshipofthereleasepointintothe dischargeline,andFig.1.2-1showsthephysicallocationsofthe dischargeoutfallandtheriver.9Thesystemsandtankswithintheplantwhichcontain radionuclides,butarenotspecificallydesignedtowithstandthe effectsofatornado,probablemaximumflood,oradesignbasis earthquake,arethereactorwatercleanupsystem,servicewater system,condensatestoragetank,andliquidradwastecollector tanks.ThereactorwatercleanupsystemislocatedinaSeismic CategoryIstructure.Theliquidradwastecollectortanksare locatedinaseismicallyanalyzedstructure.AllradioactiveliquidreleasedbyasystemortankfailurewithinaSeismicCategoryIorseismicallyanalyzedstructure exceptservicewateriscollectedbythefloordrainagesystem withinthatstructure,anditisdirectedtotheradioactive liquidwastesystemforprocessing.Asaresult,itisnot likelythatanyradioactiveliquidwillbereleasedtothe environmentduetofailureofthesesystems.Someoftheservice watertreatmentchemicalsmaybeactivatedwhenthetreatedwater passesthroughthedrywellunitcoolers.Becausetheservice watersystemisaclosed,chemicallytreatedsystem,thereisno systemblowdown.Normalservicewaterlossesaretheresultof systemleakage(e.g.,pumpsealleakage,valvepackingleakage, 9 RBSUSARRevision9 11.2-15November19979etc.).Thebulkofthesystemleakagefromcomponentslocatedwithinplantstructuresisdirectedtotheliquidradwaste system.Areasoftheplantwhereservicewaterleakageisnot directedtoradwastearethedieselgeneratorbuilding,control buildingandelectricaltunnel.Thesedrainsaredirectedtothe sewagetreatmentplant,thentotheblowdownlineviaatreated wastesump.Treatmentplanteffluentsaremonitoredviagrab samples.Normalservicewatercomponents,includingpumps, valves,andflangedconnections,whicharelocatedoutsideof plantbuildingsareequippedwithbermsorotherstructuresto containleakage.
911.2.3.2DilutionFactorsTheonlydilutionfactorusedinevaluatingreleaseofradioactiveliquideffluentsisthatprovidedbythecooling towerwaterblowdownflowof2,200gpmbeforeitisdischarged intotheriver.There,itisdilutedwiththeriverwaterwhich variesfromaminimumof5.8x10 (7)gpmtoanaverageof2.2x 10 (8)gpm.Themodeofreleaseisthattreatedradioactiveeffluentsarecollectedintherecoverysampletanks.Thefilledtankissampledandthendischarged.Thetreatedandanalyzed effluentisdilutedwith2,200gpmofcoolingtowerblowdown priortodischargingintotheMississippiRiver.The concentration(expressedinCi/cc)indicatestheactivitylevels followingdilutionwithcoolingtowerblowdown.86Duringshutdownwhenthecoolingtowerblowdownisunavailable, analternatesourceofdilutionwaterwillbeprovided.8611.2.3.3EstimatedDosesAsummaryoftheestimatedannualradiationdosesfromtheradwastesystemispresentedinAppendix11A.Asshownin Appendix11A,theestimatedannualdosesfromliquideffluents arebelowthedosecriteriasetforthin10CFR50,AppendixI,and hencebelowthedosecriteriaspecifiedin40CFR190and10CFR20.
RBSUSARRevision14 11.3-1September200111.3GASEOUSWASTEMANAGEMENTSYSTEMS11.3.1DesignBases 11.3.1.1DesignObjective Theobjectiveofthegaseouswastemanagementsystemistoprocessandcontrolthereleaseofgaseousradioactiveeffluents tothesiteenvironssoastomaintainaslowasreasonably achievable,theexposureofpersonsinunrestrictedareas,to radioactivegaseouseffluents(AppendixIto10CFR50,May5, 1975).Thisistobeaccomplishedwhilemaintainingoccupational exposureaslowasreasonablyachievableandwithoutlimiting plantoperationoravailability.11.3.1.2DesignCriteria8Thegaseouseffluenttreatmentsystemsaredesignedtolimitthedosetooffsitepersonsfromroutinestationreleasesto significantlylessthanthelimitsspecifiedin10CFR20andto operatewithintheemissionratelimitsestablishedinthe technicalrequirements.
8DesignbasissourcetermsarepresentedanddiscussedinSection11.1.Correspondingexpectedradioactivegaseouseffluentsfrom allsourcesareshowninTable11.3-1ascalculatedusingthe datashowninTable11.3-2.TheseareconsistentwithNUREG 0016,Rev.1.Theannualaverageexposureatthesiteboundaryduringnormaloperationfromgaseoussourcesisnotexpectedtoexceedthedose objectivesofAppendixIto10CFR50intermsofactualdosesto actualpersons.Theradiationdosedesignbasisforthetreated offgasistodelaythegasuntiltherequiredfractionofthe radionuclideshasdecayedandthedaughterproductsareretained bythecharcoalandtheHEPAfilters.Thegaseousradwasteequipmentisselected,arranged,andshieldedtomaintainoccupationalexposureaslowasreasonably
achievable.14Anevaluationofthesystem'scapabilitytomeetconcentrationlimitsof10CFR20whenoperatingatdesignbasisfuelleakage (304,000µCi/secat30-mindecay)isincludedinTable11.3-8.
14Section11.3.2.1.14includesdiscussionofequipmentdesignwhere apotentialforexplosionexists.
RBSUSAR 11.3-2August1987ThegaseouseffluenttreatmentsystemisdesignedtotherequirementsofGeneralDesignCriteria(GDC)asfollows:GDC60Thesystemhassufficientcapacitytoreducetheoff-gasactivitytopermissiblelevelsforreleaseduringnormaloperation, includinganticipatedoperationaloccurrences,andtomakeit unnecessarytoprovideforterminationofreleasesorlimitation ofplantoperationduetounfavorablesiteenvironmental
conditions.GDC64Continuousmonitoringofactivitylevelsinthesystemupstreamofthedelaylineprovidesadvancenoticeofanypotentially significantincreaseinreleases.Continuousmonitoringofthe systemeffluent,withautomaticisolationatactivitylevels correspondingtoadministrativereleaselimitsandannunciation atlowerlevels,alongwithcontinuousmonitoringoftheplant exhaustductrelease,provideassurancethatactivityreleasesto theenvironmentareinalleventsmaintainedwithinestablished
limits.11.3.1.3EquipmentDesignCriteria Alistoftheoffgassystemmajorequipmentitemswhichincludesmaterials,ratesprocessconditions,andnumberofunits supplied,isprovidedinTable11.3-3.Equipmentandpipingwill bedesignedandconstructedinaccordancewiththerequirements oftheapplicablecodesasgiveninTable11.3-7.ThesafetyclassesofthevarioussystemsareshowninTable3.2-1.Seismiccategorysafetyclass,qualityassurance requirements,andprincipalconstructioncodesinformationis containedinSection3.2.ThesystemisdesignedtoSafety ClassificationNNS.Thereactorbuilding,auxiliarybuilding,fuelbuilding,turbinebuilding,andradwastebuildingcontainradioactivegassources.
Thedesignbasesfortheventilationsystemsforthesethree buildingsaredescribedinSection9.4.ConservativeanalysesoftheoffgassystemarepresentedinSection15.7anddemonstratethatequipmentfailureresultsin dosesthatarewellwithintheguidelinesof10CFR100.
RBSUSARRevision10 11.3-3April199811.3.2MainCondenserSteamJetAirEjectorLow-Temp(RECHAR)
SystemTheoffgasfromthemaincondensersteamjetairejectoristreatedbymeansofasystemutilizingcatalyticrecombination andlow-temperaturecharcoaladsorption(RECHARsystem).
Descriptionsofthemajorprocesscomponentsincludingdesign temperatureandpressurearegiveninTable11.3-3andinthe followingsections.11.3.2.1SystemProcessDescription Noncondensibleradioactiveoffgasiscontinuouslyremovedfromthemaincondenserbytheairejectorduringplantoperation.Theairejectoroffgasnormallycontainsactivationgases,principallyN-16,O-19,andN-13.TheN-16andO-19haveshort half-livesandarereadilydecayed.The10-minN-13ispresent insmallamountsthatarefurtherreducedbydecay.Theairejectoroffgasalsocontainsradioactivenoblegases,includingparentsofbiologicallysignificantSr-89,Sr-90, Ba-140,andCs-137.Theconcentrationofthesenoblegases dependsontheamountoftrampuraniuminthecoolantandonthe claddingsurfaces(usuallyextremelysmall)andthenumberand sizeoffuelcladdingleaks.Amaincondenseroffgastreatmentsystemhasbeenincorporatedintheplantdesigntoreducethesegaseousradwasteemissions fromthestation.Theoffgassystemusesacatalyticrecombiner torecombineradiolyticallydissociatedhydrogenandoxygen.
Aftercooling(toapproximately130°F)tostripthecondensibles andreducethevolume,theremainingnoncondensibles(principally airwithtracesofkryptonandxenon)aredelayedinthenominal 10-minholdupsystem.Thegasiscooledto45°Fandfiltered throughaHEPAfilter.Thegasisthenpassedthrougha desiccantdryerthatreducesthedewpointtoapproximately-90°F andisthenchilledtoabout0°F.Charcoaladsorptionbeds, operatinginarefrigeratedvaultatabout0°F,selectively adsorbanddelaythexenonsandkryptonsfromthebulkcarrier gas(principallydryair).Afterthedelay,thegasisagain passedthroughaHEPAfilteranddischargedtotheenvironment throughtheplantexhaustduct.1011.3.2.1.1ProcessFlowDataTheinformationsupportingtheprocessdataispresentedinReference2.Theplantexhaustductisthesinglereleasepoint forthissystemandislocatedonthereactorbuilding.The plantexhaustductisindicatedinFig.11.3-2.
10 RBSUSARRevision12 11.3-4December199911.3.2.1.2NobleGasRadionuclideSourceTermandDecayTable11.3-1listsexpectedisotopicactivitiesatthedischargeofthesystem.Theexpectedmainsteamsourcetermdata,fromwhichtheannualaveragenoblegasactivityinputtothemaincondenseroffgas treatmentsystemisderived,isdiscussedinSection11.1andis consistentwiththemethodsgiveninNUREG-0016.Thedataused tocalculategaseousreleases,includingoffgassystem radionuclidedecay,areshowninTable11.3-2.11.3.2.1.3PipingandInstrumentationDiagram(P&ID)
TheP&IDissubmittedasFig.11.3-2.Themainprocessroutingisindicatedbyaheavyline.11.3.2.1.4RecombinerSizing1210Thebasisforresizingtherecombineristomaintainthehydrogenconcentrationbelow1percentbyvolumeonadrybasisatthe outletoftherecombiner,regardlessoftheradiolytichydrogen input(uptoitsfulldesignbasisvalue).Theexithydrogen concentrationisnormallywellbelowthe1percentmaximum allowed.Thehydrogengenerationrateofthereactorisbasedon datafromnineBWRs.
101211.3.2.1.5ProcessDesignParametersTheKrandXeholduptimeiscloselyapproximatedbythefollowingequation:
T=K D M V where:T=Holduptimeofagivengas K D=DynamicadsorptioncoefficientforthegivengasM=WeightofcharcoalV=Flowrateofthecarriergasinconsistentunits.
RBSUSAR 11.3-5August1987DynamicadsorptioncoefficientvaluesforxenonandkryptonwerereportedbyBrowning (1).GEhasperformedpilotplanttestsattheirVallecitosLaboratoryandtheresultswerereportedatthe 12thAECAirCleaningConference (3).Moisturehasadetrimentaleffectonadsorptioncoefficients.Itistopreventmoisture fromreachingthecharcoalthatthe-90°F-dewpointfully redundant,adsorbentairdriersaresupplied.Thereare redundantmoistureanalyzersthatalarmonbreakthroughofthe drierbeds;however,breakthroughisnotexpectedsincethedrier bedsareregeneratedonatimebasis.Thesystemisslightly pressurizedwhich,togetherwithverystringentleakrate requirements,preventsleakageofmoistairintothecharcoal.Carriergasistheairinleakagefromthemaincondenseraftertheradiolytichydrogenandoxygenareremovedbytherecombiner.
Theairinleakagedesignbasisisconservativelysizedat40scfm total.TheSixthEditionofHeatExchangeInstituteStandards forSteamSurfaceCondensers,ParagraphSl(c)(2)indicatesthat, withcertainconditionsofstableoperationandsuitable construction,noncondensibles(notincludingradiological decompositionproducts)shouldnotexceed6scfmforlarge
condensers (4).Dresden2,Monticello,Fukushima1,Tsuruga,andKRBhavealloperatedat6scfmorbelowafterinitialstartup.
Dilutionairisnotaddedtothesystemunlesstheairinleakage islessthan6scfm.Inthatevent,6scfmisaddedtoprovide fordilutionofresidualhydrogenfromtherecombiner.An initialbleedofoil-freeairisaddedonstartupuntilthe recombinercomesuptotemperature.Anothersourceofairisthe constant1-scfmbleedthroughthestandbyrecombinertrainto preventback-seepageofhydrogenfromtheoperatingrecombinerin theeventofitsfailure.11.3.2.1.6CharcoalAdsorbers 11.3.2.1.6.1CharcoalTemperature Thecharcoaladsorbersoperateatanominal0°Ftemperature.Thedecayheatissufficientlysmallthat,evenintheno-flow condition,thereisnosignificantlossofadsorbednoblegases duetotemperatureriseintheadsorbers.Theadsorbersare locatedinashieldedroom,andmaintainedataconstant temperaturebyaredundantvaultrefrigerationsystem.Failure oftherefrigerationsystemcausesanalarminthemaincontrol room.Decayheatproducesabout60Btu/hintheadsorber charcoalduetoaninventoryof7,300curiescorrespondingto residencetimesof46hrforKrand42daysforXe.Forno-flow conditions,conservativecalculationsusingthisheatsourceand anassumedinitialtemperatureof0°Fgiveamaximumaxial temperatureofabout90°F,whichiswellbelowtheminimum charcoalignitiontemperatureof374°F.Ifapossiblefireis detectedinthecharcoalvessels,theadsorbersareisolatedfrom offgasflowandthecharcoalbypassisused.Anitrogenpurge istheninjectedupstreamofthevaultentrance,sothatfurther combustionispreventedandthecharcoaliscooledbelowits ignitiontemperature.
RBSUSARRevision8A 11.3-6October199611.3.2.1.6.2GasChannelingintheCharcoalAdsorberChannelinginthecharcoaladsorbersispreventedbysupplyinganeffectiveflowdistributorontheinlet,havinglongcolumnsand ahighbed-to-particlediameterratioofapproximately500.
Underhillhasstatedthatchannelingorwalleffectsmayreduce efficiencyoftheholdupbedifthisratioisnotgreaterthan
12 (5).Duringtransferofthecharcoalintothecharcoaladsorbervessel,radialsizingofthecharcoalisminimizedbypouringthe charcoal(bygravityorpneumatically)overaconeorother instrumenttospreadthegranulesoverthesurface.11.3.2.1.6.3CharcoalBypassMode Avalveandspectacleflangeareprovidedtobypassthecharcoaladsorbers.Themainpurposeofthisbypassistoprotectthe charcoalduringpreoperationandstartuptestingwhengas activityiszeroorverylow.8AItmaybedesirabletousethebypassforshortperiodsduringstartupornormaloperations.Thisbypassmodewouldnotbeused fornormaloperationunlesssomeunforeseensystemmalfunction necessitatesshuttingdownthepowerplantoroperatinginthe bypassmodetoremainwithinthetechnicalrequirementlimits.
Theactivityreleaseiscontrolledbyaprocessmonitorupstream oftheplantexhaustductisolationvalvethatcausesthebypass valvetocloseonahighradiationalarm.Thisinterlockcanbe defeatedonlybyakeylockswitch.Inaddition,thereisahigh-high-highalarmonthesamemonitorthatcausestheoffgas systemtobeisolatedfromtheplantexhaustductifestablished releaselimitsareexceeded.
8A11.3.2.1.7LeakageofRadioactiveGasesLeakageofradioactivegasesfromthesystemislimitedbyweldingpipingconnectionswherepossibleandusingbellowsstem sealsorequivalentvalving.Thesystemoperatesatamaximumof 7psigduringstartupandlessthan2psigduringnormal operationsothatthedifferentialpressuretocauseleakageis
small.11.3.2.1.8HydrogenConcentration8Tolimittherecombinertemperaturedelta,hydrogenconcentrationofgasesfromtheairejectoriskeptbelow4percentby maintainingadequateprocesssteamflowfordilutionatall times.Thissteamflowrateismonitoredandalarmed,andthe steamjetairejectornoncondensiblesuctionlineisisolated whenthereisinsufficientsteam.Thehydrogenconcentration itselfismonitoredbyredundanthydrogenanalyzers.Thehigh alarm,at2percenthydrogen,indicates"off-normal"operation.
8 RBSUSAR 11.3-7August198711.3.2.1.9FieldRunPipingPipingandtubing2inandunderarefieldrouted.Thisdoesnotincludemajorprocesspipingbutdoesincludedrainlines,steam lines,andsamplelineswhichareshownonFig.11.3-2.11.3.2.1.10LiquidSeals ThereareseveralliquidsealstopreventgasescapethroughdrainsshownonFig.11.3-2.Thesesealsareprotectedagainst permanentlossofliquidbyanenlargedsectiondownstreamofthe sealthatcanholdthesealvolumeanddrainsbygravityback intotheloopafterthemomentarypressuresurgehaspassed.
Eachsealhasamanualvalvethatcanbeusedtofilltheloop.
Intheeventthataloopsealgoesdry,levelsensorsinitiate closureofanisolationvalveintheloop.Sealsarealso equippedwithsolenoidvalvesthatcloseifradioactiverelease fromthissystemexceedsestablishedlimits.11.3.2.1.11SystemPerformance NoblegasactivityreleaseisgiveninTable11.3-1inunitsof Ci/yr/unit.Iodineinputintotheoffgassystemissmallbyvirtueofitsretentioninreactorwaterandcondensate.Theiodineremaining isessentiallyremovedbyadsorptioninthecharcoal.Thisis supportedbythefactthatcharcoalfiltersremove99.9percent oftheiodinein2inofcharcoal,whereasthissystemhas approximately76ftofcharcoalintheflowpath.Particulatesareremovedwitha99.95efficiencybyaHEPAfilterasgasexitsthenominal10-minholdup.Thenoblegasdecays withintheintersticesoftheactivatedcharcoalanddaughters areentrappedthere.Thecharcoalservesasanexcellentfilter forotherparticulatesandessentiallynoparticulatesexitfrom thecharcoal.ThecharcoalisfollowedwithaHEPAfilterwhich isasafeguardagainstescapeofcharcoaldust.Particulate activitydischargedfromthissystemisessentiallyzero.11.3.2.1.12IsotopicInventory TheisotopicinventoryofeachequipmentpieceisgiveninChapter12.11.3.2.1.13PreviousExperience PerformanceofasimilarsystemoperatingatambienttemperaturesandtheresultsofexperimentaltestingperformedbyGEhavebeen submittedintheGeneralElectricCompanyproprietarytopical report,"ExperimentalandOperationalConfirmationofOffGasSystemDesignParameters (2)."Non-proprietaryportionsofthisinformationarereportedinReference3.
RBSUSAR 11.3-8August198711.3.2.1.14SingleFailuresandOperatorErrorsDesignprovisionsareincorporatedwhichprecludetheuncontrolledreleaseofradioactivitytotheenvironmentasa resultofanysingleoperatorerrororofanysingleequipment malfunctionshortofthecatastrophicequipmentfailures describedinChapter15.Ananalysisofsingleequipmentpiece malfunctionsisprovidedinTable11.3-6.Designprecautionstakentopreventuncontrolledreleasesofactivityincludethefollowing:1.Thesystemdesignseekstoeliminateignitionsourcessothatahydrogendetonationishighlyunlikelyeven intheeventofarecombinerfailure.2.Thesystempressureboundaryisdetonation-resistant,despitethemeasurestakentoavoidapossible
detonation.3.Alldischargepathstotheenvironmentaremonitored:thenormaleffluentpathbytheprocessandeffluent radiationmonitoringsystem(Section11.5);general plantareasbythearearadiationmonitoringsystem (Section12.3.4).4.Dilutionsteamflowtothesteamjetairejectorismonitoredandalarmed,andthevalvingisrequiredto besuchthatlossofdilutionsteamcannotoccur withoutcoincidentlossofmotivesteam,sothatthe processgasissufficientlydilutedifitisflowingat
all.11.3.2.1.15MaintainabilityofGaseousRadwasteSystemDesignfeatureswhichreduceoreaserequiredmaintenanceorwhichreducepersonnelexposureduringmaintenanceincludethe
following:1.Redundantcomponentsforactive,in-processequipmentpieces,excludingtheoffgascondenserandwater
separator.2.Norotatingequipmentintheradioactiveprocessstream,butlocatedwheremaintenancecanbeperformed whilethesystemisinoperation,orinnonradioactive
streams.3.Blockvalveswithairbleedpressurizationformaintenanceofthedesiccantdryerwhichisrequired duringplantoperation.4.Shieldingofnonradioactiveauxiliarysubsystemsfromtheradioactiveprocessstream.
RBSUSAR 11.3-9August1987Designfeatureswhichreduceleakageandreleasesofradioactivematerialincludethefollowing:
1.Extremelystringentleakrat erequirementsplaceduponallequipment,piping,andinstrumentsarerequired.Theserequirementsareverifiedtohavebeenmetbyperformanceofinitialserviceleaktes tsandleaktes tsofallapplicablemodificationstotheprocesssystem.Leaktestsareperformedbyacceptablemethodscapableofaccuratedetectionofleakswithinthespecifiedmaximumallowablel eakrateforthatportionofthes ystembeingtested.2.Useofweldedjointswhereverpracticable.3.Specificationofvalvetypeswithextremelylowleakratecharacteristics,i.e.,bellowsseal,doublestemseal,orequal.4.Useofloopsealswithenlargeddischargesectiontoavoidsyphoningandtobeself-refillingfollowinga pressuresurge.5.Specificationofstringentseat-leakcharacteristicsforvalvesandlinesdischargingtotheenvironment viaothersystems.11.3.2.2SystemDesignDescription11.3.2.2.1QualityClassificationandConstructionandTesting RequirementsEquipmentandpipingaredesignedandconstructedinaccordancewiththerequirementsoftheapplicablecodesasgivenin Table11.3-7andcomplywiththeweldingandmaterial requirementsandthesystemconstructionandtestingrequirements asfollows.11.3.2.2.2SeismicDesign 11.3.2.2.2.1Equipment Equipmentandcomponentsusedtocollect,process,orstoregaseousradioactivewasteareclassifiedasnonseismic.Thesupportelements,includingtheskirts,legs,andanchorbolting,forthecharcoaladsorbertanksoftheoffgassystem aredesignedasfollows:1.Thefundamentalfrequencyofthecharcoaladsorbertanks,includingthesupportelements,isgreaterthan 33Hertz.
RBSUSAR 11.3-10August1987
- 2. Thecharcoaladsorbertanksaremountedonthebasematofthebuildinghousingthetanks.3.Thecharcoaladsorbertanks,includingthesupportelements,aredesignedwithaverticalstatic coefficientof0.11gandahorizontalstatic coefficientof0.28g.4.Thestresslevelsinthesupportelementsofthecharcoaladsorbertanksdonotexceed1.33timestheallowablestresslevelspermittedbytheAISCManual ofSteelConstruction,SeventhEdition,1970.TheseseismiccriteriaareconsideredtomeettherequirementsofRegulatoryGuide1.143(formerlyBranchTechnicalPositionETSB No.11-1).FurtherdiscussionmaybefoundinReference7.11.3.2.2.2.2BuildingsHousingGaseousRadioactiveWasteProcessingSystemsTheequipmentandthecomponentsoftheoffgassystemarehousedintheoffgasareaoftheturbinebuilding.Theturbine buildingisclassifiedasnon-seismicandisdesignedand analyzedinaccordancewithseismiccriteriadescribedin Sections3.7.2.17Aand3.8.4.4.9.11.3.2.2.3QualityControl Aprogramisestablishedtoassurethatthedesign,construction,andtestingrequirementsaremet.Thefollowingareaswillbe includedintheprogram:1.DesignandProcurementDocumentControl-Proceduresareestablishedtoensurethatrequirementsare specifiedandincludedindesignandprocurement documentsandthatdeviationstherefromare
controlled.2.Inspection-Aprogramforinspectionofactivitiesaffectingqualityisestablishedandexecutedbyor fortheorganizationperformingtheactivitytoverify conformancewiththedocumentedinstructions, procedures,anddrawingsforaccomplishingthe
activity.3. Handling,Storage,andShipping-Proceduresare establishedtocontrolthehandling,storage, shipping,cleaning,andpreservationofmaterialand equipmentinaccordancewithworkandinspection instructionstopreventdamageordeterioration.
RBSUSAR 11.3-11August19874.Inspection,Test,andOperatingStatus-Proceduresareestablishedtoprovidefortheidentificationsofitemswhichhavesatisfactorilypassedrequired inspectionsandtests.5.CorrectiveAction-Proceduresareestablishedtoassurethatconditionsadversetoquality,suchas failures,malfunctions,deficiencies,deviations, defectivematerialandequipment,andnonconformances, arepromptlyidentifiedandcorrected.11.3.2.2.4WeldingAllweldingconstitutingthepressureboundaryofpressureretainingcomponentsisperformedbyqualifiedweldersemploying qualifiedweldingproceduresaccordingtoTable11.3-7.
Nonconsumableweldinsertsareprohibitedinprocesslinesunless theyaregroundoutaftertheweldiscompleted.11.3.2.2.5Materials Materialsforpressureretainingcomponentsofprocesssystemsareselectedfromthosecoveredbythematerialspecifications listedinSectionII,PartAoftheASMEBoilerandPressure VesselCode,exceptthatmalleable,wrought,orcastiron materials,orplasticpipeisnotused.Thecomponentsmeetall ofthemandatoryrequirementsofthematerialspecificationswith regardtomanufacture,examination,repair,testing, identification,andcertification.Adescriptionofthemajorprocessequipment,includingthedesigntemperatureandpressureandthematerialsof construction,isgiveninTable11.3-3.ImpacttestingofcarbonsteelcomponentsoperatingatcoldtemperaturesisinaccordancewithParagraphUG84,SectionVIII, ofASME"PressureVessel-Division1."11.3.2.2.6ConstructionofProcessSystems Pressureretainingcomponentsofprocesssystemsutilizeweldedconstructiontothemaximumpracticableextent.Processpiping systemsincludethefirstrootvalveonsampleandinstrument lines.Processlinesarenotlessthan3/4-innominalpipesize.
Sampleandinstrumentlinesarenotconsideredasportionsofthe processsystems.Flangedjointsorsuitablerapiddisconnect fittingsarenotusedexceptwheremaintenancerequirements clearlyindicatethatsuchconstructionispreferable.Screwed connectionsinwhichthreadsprovidetheonlysealarenotused.
Screwedconnectionsbackedupbysealweldingormechanical jointsareusedonlyonlinesof3/4-innominalpipesize.In lines3/4-inorgreater,butlessthan21/2-innominalpipe RBSUSAR 11.3-12August1987size,sockettypeweldsareused.Inlines21/2-innominalpipesizeandlarger,pipeweldsareofthebuttjointtype,but backingringsarenotusedinlinescarryingsludges,resins, etc.11.3.2.2.7SystemIntegrityTesting Completedprocesssystemsarepressuretestedtothemaximumpracticableextent.Pipingsystemsarehydrostaticallytestedin theirentirety,utilizingavailablevalvesortemporaryplugsat atmospherictankconnections.Hydrostatictestingofpiping systemsisperformedatapressure1.5timesthedesignpressure, butinnocaseatlessthan75psig.Thetestpressureisheld foraminimumof30minwithnoleakageindicated.Pneumatic testingmaybesubstitutedforhydrostatictestinginaccordance withtheapplicablecodes.11.3.2.2.8InstrumentationandControl Thissystemismonitoredbyflow,temperature,pressure,andhumidityinstrumentation,andbyhydrogenanalyzerstoensure correctoperationandcontrol.Table11.3-5liststheprocess parametersthatareinstrumentedtoalarminthemaincontrol room.Italsoindicateswhethertheparametersarerecordedor justindicated.Instrumentationalarmsonthestandbyrecombiner trainaredeactivatedinordertoeliminatecontinuous, operationallymeaninglessalarms,andtherebyimproveoperator responsetoimportantprocessvariablesontheoperating recombinertrain.Theoperatorisincontrolofthesystemat alltimes.Aradiationmonitoraftertheoffgascondensercontinuouslymonitorsradioactivityreleasefromthereactorandinputtothe charcoaladsorbers.Thisradiationmonitorisusedtoprovidean alarmonhighradiationintheoffgas.Aradiationmonitorisalsoprovidedattheoutletofthecharcoaladsorberstocontinuouslymonitortheratefromthe adsorberbeds.Thisradiationmonitorisusedtoisolatetheoff gassystemonhighradioactivitytopreventtreatedgasof unacceptablyhighactivityfromenteringtheplantexhaustduct.Theactivityofthegasenteringandleavingtheoffgastreatmentsystemiscontinuouslymonitored.Thus,system performanceisknowntotheoperatoratalltimes.Provisionis madeforsamplingandperiodicanalysisoftheinfluentand influentgasesforpurposesofdeterminingtheircompositions.
Thisinformationisusedincalibratingthemonitorsandin relatingthereleasetocalculatedenvironsdose.Process radiationinstrumentationisdescribedinSection11.5.2.
RBSUSAR 11.3-13August1987Environmentalmonitoringisused;however,attheestimatedlowdoselevels,itisdoubtfulthatthemeasurementscandistinguish dosesfromtheplantfromnormalvariationinbackground
radiation.11.3.2.2.9DetonationResistance Thepressureboundaryofthesystemisdesignedtobedetonationresistant.Thepressurevesselsaredesignedtowithstand 350psigstaticpressure,andpipingandvalvingaredesignedto resistdynamicpressuresencounteredinlongrunsofpipingat thedesigntemperature.Thisanalysisiscoveredina proprietaryreportsubmittedtotheNRC (6).Usingthisreport (6),adesignercanobtaintherequiredwallthicknessofaspecificequipmentdesign,whichnormallyor possiblycontainsadetonablemixtureofhydrogenandoxygen, whichisthentranslatedtothecorresponding detonation-containing,staticequipmentpressureratingbyusing anappropriatecodecalculation.Themethodassumestheabsenceofsimultaneoussecondaryeventssuchasearthquakes.Thisprocedureisthesimplestthathasbeenfoundthatdoesnotincludeadetailedandlaboriousanalysisofthegasdynamicsof thesystem.Itresultsinadesignthatsustainsthewhole envelopeoffeasibledetonations.11.3.2.2.10OperatorExposureCriteriaandControls Thissystemisnormallyoperatedfromthemaincontrolroom.Equipmentandprocessvalvescontainingradioactivefluidare placedinshieldedcellsmaintainedatapressurelessthanthat ofnormallyoccupiedareas.11.3.2.2.11EquipmentMalfunction Malfunctionanalysis,indicatingconsequencesanddesignprecautionstakentoaccommodatefailureofvariouscomponentsof thesystem,isgiveninTable11.3-6.11.3.2.2.12PreviousExperience AsystemwithsimilarequipmentisinserviceattheKRBplantinGermany.ItsperformanceisreviewedinReference2.The TsurugaandFukushimaIplantsinJapanhavesimilarrecombiners inservice.Similarsystems(ambienttemperaturecharcoal)are inserviceatDresden2and3,Pilgrim,QuadCities1and2, Nuclenor,Hatch,BrownsFerry1,2and3,andDuaneArnold.
RBSUSAR 11.3-14August198711.3.2.3OperatingProcedure11.3.2.3.1PrestartupPreparations Priortostartingthemainsteamjetairejectors(SJAE),thecharcoalvaultiscooledtonear0°F,theglycolcooleris chilledtonear35°Fandglycoliscirculatedthroughthecooler condenser,adesciccantdryerisregeneratedandvalvedin,the offgascondensercoolingwaterisvalvedin,andtherecombiner heatersareturnedon.11.3.2.3.2Startup Asthereactorispressurized,preheatersteamissuppliedandairisbledthroughthepreheaterandrecombiner.Therecombiner ispreheatedtoatleast225°Fwiththisairbleedand/orby admittingsteamtothefinalSJAE.Withtherecombiners preheated,andthedesiccantdrierandcharcoaladsorbersvalved in,theSJAEstringisstarted.Thebleedairisterminated.As thecondenserispumpeddownandthereactorpowerincreases,the recombinerinletstreamisdilutedtolessthan1percent hydrogenbyvolumebyafixedsteamsupply,andtheoffgas condenseroutletismaintainedatlessthan1percenthydrogenby
volume.11.3.2.3.3NormalOperation Afterstartup,thenoncondensiblespumpedbytheSJAEstabilize.Recombinerperformanceiscloselyfollowedbytherecorded temperatureprofileintherecombinercatalystbed.Thehydrogen effluentconcentrationismeasuredbyahydrogenanalyzer.NormaloperationisterminatedfollowinganormalreactorshutdownorascrambyterminatingsteamtotheSJAEsandthe
preheater.11.3.2.3.4PreviousExperience PreviousexperienceisreviewedinSection11.3.2.2.12.
11.3.2.4PerformanceTests Thissystemisusedonaroutinebasisanddoesnotrequirespecifictestingtoassureoperability.Monitoringequipmentis calibratedandmaintainedonaspecificscheduleandon indicationofmalfunction.11.3.2.4.1Recombiner Recombinerperformanceiscontinuouslymonitoredandrecordedbycatalystbedthermocouplesthatmonitorthebedtemperature profileandbyahydrogenanalyzerthatmeasuresthehydrogen concentrationoftheeffluent.
RBSUSAR 11.3-15August198711.3.2.4.2PrefilterTheseparticulatefiltersaretestedatthetimeoffilterinstallationorreplacementusingDOP(dioctylphthalate)aerosol todeterminewhetheraninstalledfiltermeetstheminimum in-placeefficiencyof99.95percentretention.TheDOPfromfiltertestingisnotallowedintothedesiccantortheactivatedcharcoal.Thisequipmentisisolatedduringfilter DOPtestingandisbypasseduntiltheprocesslineshavebeen purgedclearoftestmaterial.BecausetheDOPwouldhaveadetrimentaleffectonthedesiccantandcharcoal,thisfilterisnotperiodicallytested.Thisis justifiedbecausethemainfunctionofthisprefilteristo preventthelong-liveddaughtersoftheradioactivexenons generatedintheholduppipefromdepositinginthedownstream equipment,therebyminimizingcontamination.Leakagethroughthe filterhasnoeffectonenvironmentalrelease.11.3.2.4.3DesiccantGasDrier Desiccantgasdrierperformanceiscontinuouslymonitoredbyanon-streamhumidityanalyzer.11.3.2.4.4CharcoalPerformance Theabilityofthecharcoaltodelaythenoblegasescanbecontinuouslyevaluatedbycomparingactivitymeasuredand recordedbytheprocessactivitymonitorsattheexitoftheoff gascondenserandattheexitofthecharcoaladsorbers.Experiencewithboilingwaterreactorshasshownthatthecalibrationoftheoffgasandplantexhaustducteffluent monitorschangeswithisotopiccontent.Isotopiccontentcan changedependingonthepresenceorabsenceoffuelcladding leaksinthereactorandthenatureoftheleaks.Becauseof thispossiblevariation,themonitorsarecalibratedagainstgrab samplesperiodicallyandwhenevertheradiationmonitorafterthe offgascondensershowssignificantvariationinnoblegas activityindicatingasignificantchangeinplantoperations.Grabsamplepointsarelocatedupstreamanddownstreamofthefirstcharcoalbedanddownstreamofthelastcharcoalbedand canbeusedforperiodicsamplingifthemonitoringequipment indicatesdegradationofsystemdelayperformance.11.3.2.4.5PostFilter Oninstallation,replacements,andatperiodicintervalsduringoperation,theseparticulatefiltersaretestedusingaDOPsmoke testorequivalent.
RBSUSAR 11.3-16August198711.3.2.4.6PreviousExperiencePreviousexperienceisreviewedinSection11.3.2.2.12.
11.3.2.5OtherRadioactiveGasSources Radioactivegasesarepresentinthepowerplantbuildingsasaresultofprocessleakageandsteamdischarges.Theprocess leakagecreatestheradioactivegasesintheairdischarged throughtheventilationsystem.Thedesignoftheventilation systemisdescribedinSection9.4.Theradiationactivity levelsfromtheventilationsystemaretreatedinChapter12.
Thebuildingvolumesandventilationflowratesareshownin Chapter9.Thesteamdischargestothesuppressionpoolreleaseradioactivegasestotheprimarycontainment.Theactivityreleasedtothe suppressionpoolistheproductoftheactivityperunitvolume, asshowninSection11.1,andthequantityofsteamdischarged.
Thequantityofactivitywhichbecomesairbornedependsonmany factors,suchaswatertemperature,nuclidespecie,evolution rate,etc.Atabulationoftheexpectedfrequencyandthe quantityofsteamdischargedtothesuppressionpoolisprovided inTable11.3-9.11.3.3RadioactiveReleases 11.3.3.1ReleasePoints Theplantairborneradioactivereleasestotheenvironsarefromthreemonitoredroof-ventlocationsorpoints.Thesepointsare theplantexhaustduct,thefuelbuildingexhaustduct,andthe radwastebuildingexhaustduct.Theplantexhaustductisabovethereactorbuildingdomewhichisthetalleststructureinthepowerblock.Themainplant exhaustductreleasesventilationairfromthefollowingplant areasandsystems:1.Reactorbuilding2.Auxiliarybuilding 3.Turbinebuilding 4.Plantpipingandelectricaltunnels 5.Backwashreceivingtankvent 6.Samplestationvents 7.Turbineglandsealexhauststeamsystem RBSUSAR 11.3-17August19878.Offgassystem9.Mechanicalvacuumpumpexhaust.Thefuelandradwastebuildingsexhaustductsreleaseventilationairfromtheirrespectiveventilationsystems.Theseventilation systemsincludesamplestationvents,tankvents,spentfuelpool sweepgassystem,andbuildingareaventilationexhaust.11.3.3.2GlandSealSystem Thissystemisprovidedwithseparatecleansteammadefromdemineralizedcondensate.Theeffectofcleansteamutilization isnegligibleactivityreleasesfromtheturbineglandsealing
system.11.3.3.3MechanicalVacuumPump ActivityreleasesfromthemechanicalvacuumpumparepresentedinTable11.3-1.Themechanicalvacuumpumpisoperatedfor shortperiodsoftimeduringstartups.Theeffluentfromthe mechanicalvacuumpumpisroutedtotheiodinefiltrationunit beforebeingdischargedtotheenvironsthroughtheplantexhaust
duct.11.3.3.4VentilationReleases Expectedventilation,offgas,anddrywellpurgereleasesarepresentedinTable11.3-1.Theconservativeestimatedreleases fromventilationandmechanicalvacuumpumparebasedon
NUREG-0016.11.3.3.5DilutionFactors Theatmosphericdilutionfactorassociatedwithnormalplantreleasesisbasedupontheaverageannualmeteorological conditionsapplicabletothesiteaswellastheeffective releaseheightoftheeffluentdischargepathway.Thesite meteorologicalconditionsaredefinedinSection2.3.11.3.3.6EstimatedDoses Themaximumhypotheticalgammaairdoseandbetaairdoseoccurinthewestdirectionattherestrictedareaboundary.Thedoses atthislocationareestimatedtobe7.0mrad/yrgammaand6.6 mrad/yrbetaascomparedwiththeAppendixIdesignobjectivefor gammaandbetaairdosesof10.0mrad/yrand20.0mrad/yr, respectively.
RBSUSAR 11.3-18August1987AsummaryoftheestimatedannualradiationdosesispresentedinAppendix11A.AsshowninAppendix11A,theestimatedannual dosesfromgaseouseffluentsarebelowthedosecriteriaset forthin10CFR50AppendixIandhencewellbelowthedose criteriaspecifiedin40CFR190and10CFR20.11.3.3.7MainCondenserSteamJetAirEjectorLow-Temperature(RECHAR)SystemTheestimatedannualreleaseofnoblegasesduringnormaloperationisgiveninTable11.3-1.Valuesforeachnuclideare giveninCi/yr/unit.Assumptionsusedtodeterminethese releasesarelistedinTable11.3-2.
RBSUSAR 11.3-19August198711.3References1.Browning,W.E.,etal.RemovalofFissionProductGasesfromReactorOffGasStreamsbyAdsorption.(ORNL)CF59-6-47,June11,1959.2.Miller,C.W.ExperimentalandOperationalConfirmationofOffGasSystemDesignParameters.NEDO-10751,January1973.
(Proprietary)3.Siegwarth,D.P.MeasurementofDynamicAdsorptionCoefficientsforNobleGasesonActivatedCarbon.12thAEC AirCleaningConference.
4.St andardsforSteamSu rfaceCondensers,SixthEdition,HeatEx hangeInstitute,NewYork,NY,1970.5.Underhill,Dwight,etal.DesignofFissionGasHoldupSystem.ProceedingsoftheEleventhAECAirCleaning Conference,1970,p.217.6.Nesbitt,L.B.DesignBasisforNewGasSystems.NEDE-11146,July1971.(Proprietary)7.NUREG-0124(Supplement1toNUREG-75/110"SafetyEvaluationReportRelatedtothePreliminaryDesignoftheGESSAR-238 NuclearIslandStandardDesign,"USNuclearRegulatory Commission,September1976,p.3-1and3-2.
RBS USAR Revision 8 11.4-1 August 1996 11.4 RADIOACTIVE SOLID WASTE SYSTEM8 3The objective of the radioactive solid waste system is to collect, monitor, process, and packagesolid wastes for shipment offsite. Processing of waste is currently being performed by RBS personnel. Vendors may be used in the future depending on processing needs and vendor availability. Each vendor's specific system components are as described in their approved Topical Report. The solid waste system is located in the radwaste building.
3 811.4.1 Design Bases 11.4.1.1 Power Generation Design Bases3The solid waste system accepts sludges from the phase separator and backwash tanks in the liquidradwaste system. These wastes consist of spent resin beads, resin fines, and sludges in varying proportions as described in Section 11.2. The solid waste system is designed to pump wet wastes to portable skid-mounted equipment for processing. Current methods of processing include dewatering and/or solidification. Alternative processing methods may be utilized at a later date.The system also provides a means of segregating, compacting and packaging miscellaneous dryradioactive materials, e.g., paper, rags, contaminated clothing, gloves, and shoe covers, and for packaging contaminated metallic materials and incompressible solid objects such as small tools and equipment parts.The solid waste system components permanently installed within the radwaste building, and theradwaste building itself, are in conformance with Regulatory Guide 1.143, as described in Section 11.2. Portable equipment used in the processing of solid wastes is designed in accordance with
its respective approved Topical Report.Collection, processing, packaging, and storage of radioactive wastes are performed so as tomaintain any potential radiation exposure to plant personnel to as low as is reasonably achievable (ALARA) levels, in accordance with Regulatory Guide 8.8, and within the dose limits of 10CFR20. Packaging and transportation of radioactive materials are in accordance with 49CFR170-178, 10CFR30, 10CFR61, and 10CFR71; shipments are in conformance with 49CFR173 dose limits.
3 RBSUSARRevision14 11.4-2September200111.4.1.1.1ApplicableCodesandStandardsTable11.4-4liststheapplicablecodesandstandardsforequipmentinthesolidwastesystem.Thebasisforthe nonnuclearsafety(NNS)classificationandthematerial selectionsforequipmentinthesolidradwastesystemare thecriteriaasestablishedbyRegulatoryGuide1.143,as discussedinSection11.4.1.2.Theatmosphericwastesludgestoragetankisafilament-wound,fiberglass-reinforcedplastictank.Itisdesignedtomeetor exceedtheNationalBureauofStandardsVoluntaryProduct StandardPS15-69andtheAmericanSocietyforTestingand MaterialsSpecificationNo.ASTMD3299-74.11.4.1.1.2StructuralDesign14ThesolidradwasteequipmentarrangementispresentedinFig.1.2-30through1.2-32.Thestructuraldesignisdescribedin Section3.8.4.1.8.InaccordancewithRegulatoryGuide1.143and BranchTechnicalPositionETSB11-1(Revision1,April1975),the buildingisseismicallyanalyzedasdescribedinSection 3.7.2.16A.Thesolidradwastelayoutprovidesdesignfeatures consistentwithmaintainingpersonnelexposureALARA,asrequired byRegulatoryGuide8.8.
1411.4.1.2CompliancewithRegulatoryGuidesandCodeofFederalRegulationsRegulatoryGuide1.143identifiesthequalitylevel,qualitygroupclassification(safetyclass),seismicrequirements,and materialrequirementsforequipmentandstructurescontaining radioactivewastes.Thesolidwastesystemisinconformance withtheguideinthat:1.TheequipmentwithinthesystemisdesignedinaccordancewithrequirementsidentifiedinTable1oftheguide.2.Materialsforpressure-retainingcomponentsconformtotherequirementsofthespecificationformaterialsinSectionIIoftheASMECode,exceptthatnickelalloystainless steelandfiberglass-reinforcedplastic(FRP)pipingare used.TheuseofFRPpipingisrestrictedtocondensate flushconnectionstosolidwastepipingandcomponents.
Nickelalloystainlesspipingisusedinthesolidwaste systemduetoitscorrosionresistancewhentransferring acidicwastesandevaporatorbottoms.3.Foundationsandwallsoftheradwastebuilding,toanelevationabovethatsufficienttocontainthemaximumliquidinventoryexpectedinthebuilding,aredesignedto theseismiccriteriadescribedintheguide.Theyare describedinSection3.8.4.
RBS USAR Revision 11 11.4-3 October 1998Regulatory Guide 8.8 provides criteria for maintaining potential radiation exposure to plantpersonnel to ALARA levels. Design features incorporated to maintain ALARA criteria and meet the limits of 10CFR20 include:31.Totally remote operation of permanently installed wet solid waste equipment (i.e.,waste sludge tank and transfer pump) from the radwaste control panel, located in the auxiliary control room or the local panel, mounted separately from the equipment, in
the radwaste building.
32.Remote flushing of all lines containing radioactive solids.3.Minimizing lengths of piping runs.
4.Provide drip trays under pumps and control panels.
5.Waste lines and valves utilize butt weld or socket weld end connections to themaximum extent practical.11 76.Provide operator training.
7 117.Providing adequate shielding of piping and components. To the greatest extentpossible, components requiring access or maintenance are located in separate, shieldedcubicles or are otherwise provided with features to reduce personnel exposure (i.e.,
tanks are in separate shielded compartments from pumps, air-operated valves located in high radiation areas have their air sets, regulators and/or solenoid valves in low
radiation areas).8.Providing curbs to contain spills.9.Compliance with Regulatory Guide 8.10, as indicated in Section 1.8.310.Potentially contaminated exhaust air from the vendor processing equipment is routed tothe radwaste building ventilation system.CNSI, or any other vendor used, operates under and is subject to the River Bend Station plant specific Radioactive Waste Process Control Plan.
3 RBS USAR Revision 11 11.4-4 October 19983All documents, procedures, and drawings used in the fabrication, testing, operation, andmaintenance of the solid waste equipment are developed and controlled in accordance with the provisions established in the Code of Federal Regulations, Title 10CFR Part 50, Appendix B, Sections V and VI. All vendors are required to follow RBS Radiation Protection Procedures in processing radwaste in order to maintain their occupational radiation exposure ALARA. A Radiation Work Permit (RWP) is issued to the vendor's operator prior to beginning operations.
3Packaging and transportation of radioactive materials are accomplished in accordance with 49CFR, 10CFR71, Appendix E, and 10CFR61.3Depending on the specific processing method being used, one or more approved Topical Report(s) describe the specific process. Refer to the applicable Topical Report for details concerning vendor's implementation of the requirements of 10CFR Parts 20, 50, 61, and 71, and Regulatory Guides 1.143, 8.8, and 8.10.
311.4.2 System Description 11.4.2.1 General Description The solid radwaste system consists of the following:1.One waste sludge tank, complete with level detection devices and mixing and flushingequipment.2.One waste sludge pump with associated controls and instrumentation.3.One indoor, electric, overhead, single-trolley bridge crane 4.One waste compactor11 3 1Wastes consisting of spent resin beads, resin fines, filter sludges, and other processing mediafrom the liquid radwaste system are collected and mixed in the waste sludge tank or may be delivered directly to the portable processing system. If the waste is to be solidified, the solids are mixed for uniform dispersion of activity and analyzed. If the wastes are to be dewatered, a representative sample will be obtained via an Isolok sampler system or manually by the dip sampling method. Refer to the applicable Topical Report for details concerning the specific vendor's subsystem to be used for waste processing. The waste sludge system is presently being bypassed and all solid waste is being pumped to the processing unit where it is sampled and analyzed prior to shipping. This operational configuration will be continued until the waste sludge system is actually needed (i.e., waste evaporators put into service).
1 3 11 RBS USAR Revision 11 11.4-5 October 19983Note:Currently applicable License Topical Reports include CNSI-2(4313-01354-01PA), CNSI (DW-11118-01-P-A) and CNSI (RDS-25506-01-P-A).
3A physical layout drawing illustrating the solid waste packaging, storage, and shipping areas ofthe radwaste building is presented in Fig. 1.2-30 through 1.2-32. Table 11.4-1 lists annual waste volumes, specific activities, and curie content of solid waste based on the radioactive source terms discussed in Section 11.1 and operating plant data.11.4.2.2 Component Description A description of the permanent solid waste system components, including materials ofconstruction, as shown in the process flow diagram, is given in Table 11.4-3.The following is a functional description of the permanent system components:3 111.Waste Sludge Tank - This tank provides the capability for mixing various types of wastesprior to processing. An agitator provides a homogeneous waste slurry for feeding to theportable waste solidification/dewatering system. The tank is vented to the radwaste building ventilation system. An overflow from the tank is returned to the liquid radwaste
backwash tank for reprocessing.
112.Waste Sludge Pump - This pump transports the homogeneous waste slurry from the wastesludge tank to the processing equipment.
3 113.Bridge Crane - This crane is controlled locally using a hand-held radio controller. It is theprimary means of moving waste containers from the fill area to the solid waste storage area and from the waste storage area to the shipping area. The crane is also used for moving empty containers to the fill area.
114.Waste Compactor - This unit is designed to reduce the volume of compressible dryradioactive wastes. The compactor is vented through a hooded exhaust fan and filter in order to control airborne particles during dry waste compaction.
RBS USAR Revision 11 11.4-6 October 199811.4.2.3 System Operation 11.4.2.3.1 General Operation11 3Operation of the solid radwaste system is described in Section 11.4.2.1. The High IntegrityContainer/liner will be based on activity levels, volume, processing method, or vendor used.
Processing takes place in a controlled area. RBS identifies the radionuclides and the curie content
for the processed waste prior to shipping the waste.
3 1111.4.2.3.2 Instrumentation and ControlsInstrumentation and controls are provided for indication of process operation, equipmentperformance status, and remotely located control of process equipment. The main control panel for the permanent solid waste equipment is located in the auxiliary control room. Level and temperature indicators as well as high/low level alarms are provided for the waste sludge tank.
The waste sludge pump automatically shuts off when a low level is indicated in the waste sludge tank. High pressure and low flow indicators and alarms are provided for the waste sludge pump.
If high pressure or low flow is indicated, the waste sludge pump automatically recirculates the solid waste back to the waste sludge tank. Control switches for the waste sludge pump and the waste sludge tank agitator are also located on the radwaste control panel in the auxiliary control room.11 3The processing system and liner filling are monitored by closed circuit television (CCTV). Level indication and alarm, and high-high level automatic shutoff features, are incorporated into the process controls to prevent overflows from the liners containing liquids, sludges, and spent resins.
All equipment provided within the waste processing system is designed to fail in the safe position. Refer to the applicable topical report for the specific process used for a complete description of the instrumentation and controls system.
3 11 RBS USAR Revision 24 11.4-7 11.4.2.3.3 Dry Waste Disposal 11 8 The solid wa ste system also disposes of dry wastes consisting of dry filter media, contaminated clothing, small tools, rags, miscellaneous paper, glassware, wood, and equipment and miscellaneous wastes which cannot be effectively decontaminated prior to packaging. The segregation and removal of clean waste is usually performed to minimize the volume of waste to be buried. This may be performed on or off site. Temporary vendor services or Entergy facilities may be used to accomplish this. Compressible waste then may be compacted, using a compactor, into metal drums or boxes on or off site to reduce its volume.
Compressib le wastes are compacted by a compactor into 52- or 55-gallon drums to reduce their volume. The compactor exhaust is filtered to minimize airborne contamination during compaction. Noncompressible wastes are packaged manually in appropriate containers. The packaging of large waste materials and equipment that has been activated during reactor operation is handled on a case-by-case basis. Storage space for approximately 26,800 cu.
ft. Of miscellaneous dry active waste in drums and boxes is provided. This waste is stored in the radwaste building, the low level radwaste storage facility, or approved temporary storage facilities. These facilities are used to store radioactive material, compacted waste, and packaged non-compatible waste. These facilities are used to store radioactive material, compacted waste, and packaged non-compatible waste. Radiation control access barrier are used as required. Dry active wastes which cannot be packaged into drums or b oxes may be stored in a temporary dry active waste storage area of the radwaste building until transfer to one of the temporary dry active waste storage facilities. Segregation, packaging, and compacting of loose radwaste is performed prior to transfer of the waste to these facilities.
Fig. 1.2-30 through 1.2-32 show the solid waste area general arrangement.
8 11 11.4.2.3.4 Radiation Monitoring 6 3Area radiation detectors and monitors are provided as described in Section 12.3, Table 12.3-1 and Figures 12.3-6 through 12.3-9.
Area radiation detectors and monitors supporting the radioactive
solid waste system are located near: 1.Portable waste processing equipment.2.Low level compacted waste drum storage area which is in the general area on the 136' elevation of the radwaste building.These area detectors and monitors are provided to alert local personnel and the control room operator of increasing or
abnormally high radiation levels as described in Section 12.3.4.
3 6 RBS USAR Revision 11 11.4-8 October 199811.4.2.4 Postulated Accident Analysis3 11The design, fabrication, and operation of both the solid waste system and the portable wasteprocessing system are in accordance with the appropriate codes and standards to ensure the safe and reliable processing of radioactive waste. Accidents can occur which have the potential for the release of contamination to the surrounding area. In the radwaste building, the release of the contents of the regenerant evaporator is postulated, and is the maximum credible accident due to failure of any of the radwaste equipment. The radiological consequences of any solid radwaste component failure are enveloped by those based on failure of the liquid waste system as described
in Section 15.7.3.1.
11Physical features designed to control liquid spills have been incorporated into the layout of theradwaste building. The waste liner fill area is surrounded by walls on four sides and a 6-in curb on two sides to contain spills. The floor and walls to an elevation 1 ft above the floor and the curb are epoxy-coated within the spill area for ease of decontamination. The spilled liquid and decontamination liquids can be returned to the liquid waste system for reprocessing via the floor
drain lines.
311.4.2.5 Annual VolumesThe expected quantities of wet and dry waste and activities are given in Table 11.4-1. The totalactivity of the wet wastes is directly related to the activity in the liquids from each source and the decontamination factors (DF) for each process component. However, when the DF is 100 or greater, it is assumed that all the activity is transferred to the filter media or resins. It is assumed that both soluble and particulate nuclides are deposited in the demineralizers. Decay, prior to shipment, is not assumed. However, it is anticipated that, in many cases, intervals of at least 30 days will occur prior to shipment.
11.4.2.6 Packaging11 3The appropriate High Integrity Container/liner is used for package solid wastes based on activitylevels, volume, and processing method. All wastes collected in the solid radwaste system for disposal will be processed as described in Section 11.4.2.3 and shipped in accordance with regulatory and burial site requirements.
3 11 RBS USAR Revision 24 11.4-9 The expected activity levels of solid radwaste volume generated annually are given in Table 11.4-1.
11.4.2.7 Storage Facilities 8 3 Packaged p rocessed radwaste is stored in a shielded storage area in the vicinity of the liner fill area, as shown in Fig. 1.2-30. Approximately 35 filled liners can be stored in this area at one time. Filled liners are not stacked due to the height restrictions of the storage area shield walls. If additional space is required to store liners, the liners can be transferred to the low level radwaste storage facility r the height of the radwas te building storage shield walls can be increased to accommodate the stacking of liners.
The waste storage areas in the radwaste building and in the low level radwaste storage facilities can provide a combined storage capability for dewatered resins for approximately five years. Also, the combined capacity of the low level radwaste facilities and available storage in the radwaste building is approximately 26,800 cu ft of dry active waste.
This is equivalent to dry active waste storage capacity for approximately five years 11.4.2.7.1 Low Level Radwaste Storage Facility (LLRWSF)
The LLRWSF is located outside the Protected Area at plant site coordinates N15460 and E17500, see Figure 1.2-2. The facility is an 80 ft. wide by 200 ft. long by 51 ft. tall steel frame building with metal siding and designed to support a 20 ton traveling crane. The size of the facility was established based upon the total number of radioactive material containers, size of the concrete vault, and requirements for inspection aisles. The LLRWSF has the capacity to store 8 ft. x 20 ft. x 8 ft. high Sea/Land containers and 96 HICs. In general, the inspection aisles are 3 ft. wide. The facility contains twelve concrete cubicles to store HICs. Each cubicle is 16 ft. x 16 ft. x 16 ft. with 2 ft. thick concrete walls and topped with 1 ft. thick removable concrete panels. Each cubicle has the capacity to hold eight HICs, i.e. four stacked two high. The entire facility is surrounded by a 1 ft. thick by 16 ft. high concrete shield wall, except at the openings for the 3 ft. x 7 ft. personnel door and the 14 ft. x 16 ft. roll-up d oor. The LLRWSF is equipped with a natural convection ventilation system consisting of a building ridge vent, two supply fans and louvers mounted in the building walls. The system is of sufficient capacity to moderate inside temperatures for worker comfort and safety. There is no freeze protection in the facility.
The LLRWSF is provided with 480 volt electrical power to supply power for the interior and exterior lighting, the overhead traveling bridge crane, supply fans, and receptacles throughout the facility. Lightning protection is also provided and the building grounding is tied into the plant grounding system.
RBS USAR Revision 24 11.4-9a The LLRWSF is considered a storage occupancy with a fire loading classification of low hazard (NFPA-101 Section 4-2.2.2) since it is unoccupied except during the movement of radioactive material and all radioactive material is stored in noncombustible containers or within a concrete vault. In order to reduce the number of openings in the surrounding 16 ft. concrete wall for shielding purposes, only one personnel door is installed on the south end of the west wall and one roll-up door is installed in one south wall. Per NFPA 101 "Life Safety Code", Chapter 29-2.4.1, Exception No. 1, for low hazard storage occupancies only a single means of egress is required from any story or section; therefore, one exit is acceptable. Furthermore, since the LLRWSF will be unoccupied, no potable water will be required.
The LLRWSF is contained within a 6 ft. (approximately) fence to provide security as well as restricting general access to the facility.
Refer to Figure 11.4-3 for a layout of the LLRWSF. 11.4.2.7.2 Independent Spent Fuel Storage Installation (ISFSI) The ISFSI or dry fuel storage system utilized is Holtec International's HI-STORM system. As stated in Chapter 9.1.2.5, River Bend Station's ISFSI is located approximately 470 feet southwest of the Reactor Building, and 134 feet southwest of the Auxiliary Control Building. The dry fuel storage cask system has been independently reviewed and approved for use by the NRC apart from the site reactor licenses. The full description of this system is in other documents. These documents include the Holtec Certificate of Compliance (CoC), document HI-20443196, Holtec Final Safety Analysis Report (FSAR), NRC Safety Evaluation Report (SER) and the Entergy Nuclear South 10 CFR 72.212 Evaluation Report. 8 11 11 3 11.4.2.8 Shipment The packaged solid waste is transported by a licensed disposal contractor or a licensed carrier. All containers shipped are appropriately shielded to meet the Department of Transportation
radiation dose limits as described in 49CFR173. The expected annual volumes of solid radwaste to be shipped offsite are given in Table 11.4-1. The corresponding expected isotopic activity level of the solid waste is provided in
Table 11.4-2.
RBS USAR Revision 16 11.5-1 March 2003 11.5 PROCESS AND EFFLUENT RADIOLOGICAL MONITORING AND SAMPLING SYSTEMS11.5.1 Design Bases The process and effluent radiological monitoring and sampling systems are provided to allow determination of the content of radioactive material in various gaseous and liquid process and
effluent streams. The design objective and criteria are
primarily determined by the system designation of either: 1. Instrumentation systems required for safety, or 2. Instrumentation systems required for plant operation. 11.5.1.1 Design Objectives 11.5.1.1.1 Systems Required for Safety The main objective of radiation monitoring systems required for safety is to initiate appropriate manual or automatic protective action to limit the potential release of radioactive materials from the reactor vessel, primary and secondary containment, and fuel handling areas if predetermined radiation levels are exceeded in major process/effluent streams, and to protect main control room personnel throughout the course of an accident.
Additional objectives are to have these systems available under
all operating conditions including accidents. The radiation monitoring systems (RMS) provided to meet these objectives are: 1. Main steam line 162. Fuel building ventilation exhaust 3. Main control room air intakes
- 4. Containment purge isolation 1611.5.1.1.2 Systems Required for Plant Operation 8 The main objective of RMS required for plant operation is to provide operating personnel with measurement of the content of radioactive material in all potentially radioactive effluents and significantly contributing process streams. This allows
demonstration of compliance with plant normal operational
technical specifications/requirements by providing gross radiation level monitoring and collection of halogens and particulates on filters (gaseous effluents) as required by Regulatory Guide 1.21. Radiation monitoring is also provided for
major process/effluent streams to cover abnormal and accident
releases consistent with Regulatory Guide 1.97. These 8
RBS USAR Revision 16 11.5-2 March 2003 8monitors are not required to be Category I per Regulatory Guide 1.97, Table 2; however, some have upgraded capabilities in order to be available post-LOCA. Additional objectives are to initiate discharge valve isolation on the offgas or liquid
radwaste systems if predetermined release rates are exceeded and to provide for sampling at certain radiation monitor locations to
allow determination of specific radionuclide content.
8The RMS provided to meet these objectives are: 1. For gaseous effluent streams a. Radwaste building ventilation exhaust b. Main plant exhaust duct (normal range and extended range gas monitors) 2. For liquid effluent streams a. Liquid radwaste effluent 12 123. For gaseous process streams a. Offgas pretreatment
- b. Offgas post-treatment
- c. Auxiliary building ventilation
- d. Containment purge 16 e. Deleted
- f. Turbine building ventilation
g.Deleted h.Deleted i.Condensate demineralizer and offgas building ventilation
- j. Deleted k. Standby gas treatment system effluent
- l. Containment and drywell atmosphere monitoring
- m. Reactor building annulus ventilation 4. For liquid process streams
- a. Deleted 16 RBS USAR Revision 16 11.5-3 March 2003 b. Turbine plant component cooling water c.Reactor plant component cooling water 12 d.Cooling Tower blowdown line 16e. RHR heat exchanger service water effluent 12 1611.5.1.2 Design Criteria 11.5.1.2.1 Systems Required for Safety The design criteria for the safety-related radioactivity monitoring systems are that the systems: 1. Are designed to Seismic Category I criteria to withstand the effects of natural phenomena (e.g.,
earthquakes) without loss of capability to perform
their functions. 2. Perform their intended safety function in the environment resulting from normal, abnormal, and
postulated accident conditions. 3. Meet the reliability, testability, independence, and failure mode requirements of engineered safety features (ESF).4. Provide continuous outputs on main control room panels. 5. Permit checking of the operational availability of each channel during reactor operation with provision for calibration function and instrument checks. 6. Assure an extremely high probability of accomplishing their safety functions in the event of anticipated
operational occurrences. 87. Initiate prompt protective action before plant technical specification/requirements limits are
exceeded.88. Provide warning by alarm annunciation of increasing radiation levels indicative of abnormal conditions. 9. Insofar as practical, provide annunciation to indicate power failure or component malfunction. 10. Register full-scale output if radiation detection exceeds full scale.
RBS USAR Revision 16 11.5-3a March 2003 11. Have sensitivities and ranges compatible with anticipated radiation levels.
The safety-related radioactivity monitoring systems satisfy General Design Criteria (GDC) 60, 63, and 64 of 10CFR50, Appendix A. The systems meet the design requirements for Safety Class 2, Seismic Category I systems, together with the quality assurance
requirements of 10CFR50, Appendix B.
RBS USAR Revision 8 11.5-4 August 1996 11.5.1.2.2 Systems Required for Plant Operation The design criteria for operational RMS are that the systems: 1. Provide indication of radiation levels in the main control room.2. Provide warning by alarm annunciation of increasing radiation levels indicative of abnormal conditions. 3. Insofar as practical, provide annunciation to indicate power failure or component malfunction. 4. Monitor a sample representative of the bulk stream or volume.
- 5. Have provisions for calibration, function, and instrumentation checks. 86. Have sensitivities and ranges compatible with anticipated radiation levels and technical specification/requirements limits.87. Register full scale output if radiation detection exceeds full scale. Additional design criteria for the main plant exhaust duct extended range monitor and drywell and containment atmosphere monitors are
discussed in Sections 11.5.2.1.3.2.1 and 11.5.2.1.3.3. 8The monitors installed on the containment purge system, the offgas system, and the liquid radwaste treatment systems have provisions to
alarm and to initiate automatic closure of the discharge valves on
the affected treatment system before the limits specified in
technical specifications/requirements are exceeded, as required by
8The design bases conform to GDC 60, 63, and 64 of 10CFR50, Appendix A.11.5.2 System Description The process and effluent radiation monitoring system consists of a computer based digital radiation monitoring system (DRMS) and
nondigital monitors supplied as part of the reactor protection system (RPS) and offgas treatment system.
11.5.2.1Digital Radiation Monitoring System The function of the DRMS is to measure, evaluate, and report radioactivity in process streams, in liquid and gaseous effluents, and in selected plant areas, and to annunciate abnormal system
conditions. The process and effluent monitors, except as noted in Table 11.5-1, and area monitors in Table 12.3-1 constitute the DRMS.
Each monitoring channel has a RBS USAR Revision 16 11.5-5 March 2003 16microprocessor associated with the detector or sample station. The DRMS computer system continuously polls the local
microprocessors collecting and storing radiation levels, alarms and status information for these monitoring channels. This
information is available on demand for analysis of plant
conditions, trending of radiation levels, and maintenance purposes. Associated with the DRMS computers is a report processor which collects meteorological tower data. This information is combined with information from the gaseous effluent monitors to generate the gaseous release calculations
for Regulatory Guide 1.21 report generation. Monitors are provided for in the following gaseous release points:1. Main plant exhaust 2. Fuel building ventilation exhaust
3.Radwaste building ventilation exhaust 8Liquid radwaste effluent data is determined by batch sampling before release in accordance with Regulatory Guide 1.21. The isotopic analysis is used to determine the monitor setpoints.
The liquid radwaste effluent monitor terminates the release if
the technical requirements limits are exceeded.
8 16All monitoring channels have three alarm states: alert radiation, high radiation, and monitor failure. Alarms for all digital-based process monitors monitor microprocessors and are
annunciated at each DRMS CRT console. Consoles are located in the main control room, technical support center, emergency
operations facility, and radiation protection work area. System panels are provided in the main control room for safety-related effluent monitors and post-accident monitors. In the unlikely event of failure of the redundant central processors, current radiation levels, alarms, and controls for
these monitors are provided on these panels. For nonsafety-related monitors, communication interface is at the system CRT in the main control room, technical support center, emergency operation facility, and radiation protection work area.
All monitors can be communicated with at the local level by using
a portable control unit.
RBS USAR Revision 16 11.5-6 March 2003 11.5.2.1.1 DRMS Monitor Descriptions Four basic types of monitoring or sampling systems are provided as indicated in Table 11.5-1 for the DRMS process and effluent
monitoring systems; offline gas and particulate, offline gas, online steam, and offline liquid.
Offline Gas and Particulate Monitor16The typical offline gas and particulate monitor consists of an isokinetic sampling system, moving particulate filter with detector, gas sample chamber with detector, and associated pump
and valving. Connections are available for taking grab samples of the process stream, and for taking tritium samples downstream
of the filter units (effluent monitors only). Check sources that are remotely operated are provided with each detector to check the function of each channel regularly. Remote purging
capability is provided for the gas sample chamber. Detectors are
designed to obtain the nominal ranges indicated in Table 11.5-1. The isokinetic sampling systems for these monitors are designed in accordance with ANSI N13.1-1969. Flow straighteners are provided in process streams that do not meet the minimum
straight-run duct lengths specified by the standard. Sample lines from process streams in which plateout due to condensation
could be a problem have been heat traced so that particulate sampling is representative of the process stream. Plateout is
also minimized by using stainless steel for sample lines and for all surfaces of the sampler which are in contact with the sample
stream.Offline Gas MonitorThe typical offline gas monitor consists of a sampling system, fixed particulate and charcoal filters, a gas sample chamber with detector and associated pump with valving. Connections are available to facilitate taking grab samples of the process streams. All filters are removable for laboratory analysis.
Check sources and purging capabilities are provided, as described, for the offline gas and particulate monitor. Detector
type, and nominal ranges are given in Table 11.5-1.
16For post-accident monitors, multiple detectors are provided with a minimum overlap of a decade in range to cover the extended ranges indicated on gaseous channels. Sampling and collection
capability only is provided to cover the particulate channel range from 10µ to 10 uCi/cc. These monitors are also designed to perform their required function under the appropriate
environmental conditions as defined in Section 3.11.
RBS USAR 11.5-7 August 1987 Online Steam Monitor The online steam monitor consists of a detector, shielding, and a remotely operated check source. The monitor is mounted to view a steam line and shielded to obtain the sensitivities indicated in
Table 11.5-1.
Offline Liquid Monitor The typical offline liquid monitor consists of a sample chamber with detector and associated pump, piping, and valving. The detector is provided with a remotely operated check source and shielded to obtain the sensitivities indicated in Table 11.5-1. Connections for taking a grab sample from the
process stream and purging the liquid sample chamber and sample tubing are provided. Heat exchangers are provided on sampling systems for which the process stream would cause detector
failure.11.5.2.1.2 DRMS Monitoring Systems Required for Safety 11.5.2.1.2.1 Fuel Building Ventilation Exhaust One offline gas monitor and one offline gas and particulate monitor as described in Section 11.5.2.1.1 are provided for monitoring the fuel building ventilation exhaust before discharge
to the environment. These monitors function to collect data for Regulatory Guide 1.21 report generation during normal operation, and indicate airborne levels of radiation in the fuel building (Section 12.3.4).
The fuel building monitors are required for safety in the event that high airborne levels of radiation are present in the fuel
building. They divert the ventilation exhaust through the fuel
building ventilation system safety-related filter trains on a high alarm signal. The fuel building offline gas monitor has an extended range as indicated in Table 11.5-1 to cover releases throughout a design basis accident (DBA). These monitors are designed to perform their required function under all environmental conditions as defined in Section 3.11. Reliable Class 1E safety-related 120-V ac electrical power is provided to
these monitors as described in Section 8.3. 11.5.2.1.2.2 Containment Purge Isolation Monitors Redundant area monitors are provided on the containment purge system. These monitors are intended to meet the requirements of NUREG 0737 Item II.E.4.2 (Containment Isolation Dependability).
On receipt of a high radiation signal, the containment purge is isolated. Reliable safety-related Class 1E 120-V ac electrical
power is provided to these monitors as described in Section 8.3.
RBS USAR Revision 16 11.5-8 March 2003 16 11.5.2.1.2.3 Deleted 11.5.2.1.2.4 Main Control Room Air Intakes
Redundant offline gas monitors are provided at all main control room air intakes (local and remote). The main control room ventilation local intake monitors divert the intake air through safety grade filter systems on a high radiation alarm. The main control room ventilation intake monitors enable the operator to choose the least contaminated air intake throughout the course of an accident (Section 6.4) and provide an indication of airborne
radiation levels present in the main control room intake (Section 12.3.4). These monitors are also designed to perform
their required function under all environmental conditions as defined in Section 3.11. Reliable safety-related Class 1E 120-V ac electrical power is provided to these monitors as
described in Section 8.3.
11.5.2.1.2.5 Deleted 13 13 1611.5.2.1.3 DRMS Monitoring Systems Required for Plant Operations11.5.2.1.3.1 Liquid Effluent Monitors 12One monitor is provided to prohibit unidentified radioactive liquid releases from the plant: 1. Liquid radwaste effluent monitor.
12 RBSUSARRevision12 11.5-9December1999128Theliquidradwasteeffluentmonitorterminatesaliquidradwastesystemreleaseifradiationlevelsexceedthetechnical requirementlimits.Nonsafety-relatedelectricalpoweris providedtothismonitorasdescribedinSection8.3.
1211.5.2.1.3.2GaseousEffluentMonitors11.5.2.1.3.2.1MainPlantExhaustDuct Effluentfromthemainplantexhaustductismonitoredbyanextended-rangeofflinegasmonitor.Theprimaryfunctionofthis monitoristoassurethattechnicalrequirementslimitsfor releasesarenotexceeded,tocollectdataforRegulatory Guide1.21reportgeneration,andtoprovideextended-range post-accidentmonitoring.Majorprocessstreamsexhausted throughthemainplantexhaustductincludereactorbuilding ventilation,auxiliarybuildingventilation,turbinebuilding ventilation,pipingtunnelventilation,standbygastreatment systemexhaust,andoffgasbuildingventilationexhausts.
ConsistentwithRegulatoryGuide1.97,thismonitorisdesigned toperformitsrequiredfunctionunderallenvironmental conditionsasdefinedinSection3.11.Reliablesafety-related Class1E120-Vacelectricalpowerisprovidedtothismonitoras describedinSection8.3.Additionally,onenormalrangeofflinegasandparticulatemonitorisprovidedtomonitorthemainplantventilation exhaust.Thismonitorfunctionsprimarilytoassurethat technicalrequirementslimitsforreleasesarenotexceeded,and tocollectdataforRegulatoryGuide1.21reportgeneration.
Nonsafety-relatedelectricalpowerisprovidedtothismonitoras describedinSection8.3.11.5.2.1.3.2.2FuelBuildingVentilationExhaust Onenormalrangeofflinegasandparticulatemonitorisprovidedtomonitorthefuelbuildingexhaust.Themonitorfunctionsare describedinSection11.5.2.1.2.1.11.5.2.1.3.2.3RadwasteBuildingVentilationExhaust Oneofflinegasmonitorandoneofflinegasandparticulatemonitorareprovidedtomonitortheradwastebuildingventilation exhaust.Thesemonitorsfunctionprimarilytoassurethat technicalrequirementlimitsforreleasesarenotexceeded,to monitorairbornelevelsofradiationintheradwastebuilding (Section12.3.4),andtocollectdataforRegulatoryGuide1.21 reportgeneration.Gasesfromtheradwastetanksarefiltered anddischargedthroughtheradwaste buildingventilationexhaustduct.Theradwastebuildingoffline gasmonitorhasanextendedrangetocoverpost-accident monitoringrequirementsforradwastebuildingeffluents.
Nonsafety-relatedelectricalpowerisprovidedtothesemonitors asdescribedinSection8.3.
8 RBSUSAR 11.5-10August198711.5.2.1.3.3ProcessVentilationMonitorsOfflinegasandparticulatemonitorsareprovidedonthefollowingprocessventilationstreams:1.Auxiliarybuildingventilationexhaust2.Containmentpurgeexhaust(gasmonitoronly) 3.Turbinebuildingventilationexhaust(includingcondensatedemineralizerarea)4.Offgasbuildingventilationexhaust5.Standbygastreatmenteffluent(gasmonitoronly)Thefunctionoftheprecedingmonitorsistoidentifysourcesofradiationinmainplantexhaustducteffluentinaccordancewith RegulatoryGuide1.21formonitoringseparatestreamsintoa commonreleasepointforbetterresolution.Thesemonitorsalso functiontoindicateairbornelevelsofradiationinthe correspondingplantbuildings(Section12.3.4).Thecontainmentpurgeexhaustmonitorisolatesthenormalcontainmentpurgeonahighradiationalarm.Thestandbygas treatmentsystemeffluentismonitoredtoensureadequate performanceofthesystemandtoalarmifreleaselimitsare exceeded.Nonsafety-relatedelectricalpowerisprovidedto thesemonitorsasdescribedinSection8.3.11.5.2.1.3.4ContainmentandDrywellAtmosphere Offlinegasandparticulatemonitorsareprovidedtomonitorthecontainmentanddrywellairbornelevelsofactivity.Thedrywell monitorpullsasamplefromthedrywellthroughthemonitoring systemlocatedinthecontainmentandreturnsthesampleexhaust tothedrywell.Thecontainmentmonitorislocatednearthe reactorbuildingventilationunitcoolersat162ft0inofthe reactorbuilding.Theunitcoolersprovidemixedairthatis representativeofthecontainmentatmosphere.Thecontainmentanddrywellatmospheremonitorsareprovidedtoaidindetectingreactorcoolantpressureboundary(RCPB)leakage inaccordancewithRegulatoryGuide1.45.Theyaredesignedto remainfunctionalduringandaftertheseismicloadingconditions asdefinedinSection3.7.Thecontainmentatmospheremonitor alsofunctionstoindicateairborneradiationlevelsin containment(Section12.3.4)formaintainingworkers'exposure ALARA.Reliablesafety-relatedClass1E120-Vacelectrical powerisprovidedtothesemonitorsasdescribedinSection8.3.
RBS USAR Revision 16 11.5-11 March 2003 11.5.2.1.3.5 Process Liquid Monitors The following process streams are monitored by offline liquid monitors for detection of radiation levels: 1612 1. Deleted 2. Reactor plant component cooling water
- 3. Cooling tower blowdown line
- 4. RHR Heat Exchanger Service Water Effluent The reactor plant component cooling water monitors detect and alarm contamination of the circulating water in these systems.
The cooling tower blowdown line monitor detects and alarms on increase in background or contamination in circ water cooling tower blowdown. Nonsafety-related electrical power is provided
to these monitors as described in Section 8.3. An offline liquid monitor is provided to monitor the service water effluent on each of the two RHR heat exchanger trains.
These monitors function to detect and alarm contamination of the service water effluent due to leaks in the heat exchangers following a DBA or under normal operating conditions. These monitors are also designed to perform their required function under all environmental conditions as defined in section 3.11
except an HELB or MELC; however, they are not required to function after an HELB or MELC. Reliable safety-related Class 1E 120-V ac electrical power is provided to the monitors as
described in Section 8.3. 11.5.2.1.3.6 Process Gaseous Monitors The following process gaseous streams are monitored for radiation level and alarm if abnormal levels are detected:
- 1. Deleted 2. Reactor Building Annulus Ventilation 8 8 12Redundant offline gas monitors are provided on the reactor building annulus ventilation exhaust. The annulus monitors
function to indicate airborne levels of activity in the annulus area (Section 12.3.4). On a high radiation alarm signal the containment, auxiliary, and annulus ventilation exhaust is
diverted through the SGTS.
16 RBS USAR Revision 16 11.5-11a March 2003 1612These monitors are also designed to perform their required function under all environmental conditions as defined in Section 3.11. Reliable safety-related Class 1E 120-V ac electrical power is provided to these monitors as described in
Section 8.3.
1211.5.2.2 Noncomputer Based Process Radiation Monitoring Systems 11.5.2.2.1 Main Steam Line Radiation Monitoring System This system monitors the gamma radiation level exterior to the main steam lines. The normal radiation level is produced
primarily by coolant activation gases plus smaller quantities of fission gases being transported with the steam. In the event of a gross release of fission products from the core, this
monitoring system provides channel trip signals to the containment and reactor vessel isolation control systems to
initiate protective action. 8 The system consists of two redundant instrument channels. Each channel consists of a local detector (gamma-sensitive ion
chamber) and a main control room log radiation monitor. Power
for two channels (A and C) is supplied from RPS bus A.
8 16 RBS USAR Revision 16 11.5-12 March 2003 8The detectors are physically located near the main steam lines just downstream of the outboard main steam isolation valves (MSIV). The detectors are geometrically arranged so that this system is capable of detecting significant increases in radiation level with any number of main steam lines in operation.
Table 11.5-1 lists the range of the detectors. 16Additional description and isolation functions are discussed in USAR section 7.3.1.1.2.3. 811.5.2.2.2 Off Gas Pretreatment Radiation Monitoring System This system monitors radioactivity in the condenser off gas before it enters the delay pipe and after it has passed through
the off gas condenser and water separator. The monitor detects the radiation level which is attributable to the fission gases produced in the reactor and transported with steam through the
turbine to the condenser. A continuous sample is extracted from the off gas pipe via a sample line. It is then passed through a sample chamber and a
sample panel before being returned to the suction side of the steam jet air ejector (SJAE). The sample chamber is a steel pipe
which is internally polished to minimize plateout. It can be purged with room air to check detector response to background radiation by using a three-way solenoid operated valve. The valve is controlled by a switch located in the main control room.
The sample panel measures and indicates sample line flow. A sensor and converter (GM tube) is positioned adjacent to the
vertical sample chamber and is connected to a radiation monitor
in the main control room. Nonsafety-related power is supplied from the 125-V dc bus B for the radiation monitor and recorder, and from a 120-V ac local bus
for the sample and vial sampler panels.
The monitor has two trip circuits: one upscale (high) and one downscale (low). The trip outputs are used for alarm function
only. Each trip is visually displayed on the monitor and
actuates a main control room annunciator: offgas pretreat high radiation and offgas pretreat downscale. -High or low sample
line flow measured at the sample panel actuates a main control
room off gas sample high-low flow annunciator.
16 RBS USAR Revision 22 11.5-13 The radiation level output by the monitor can be directly correlated to the concentration of the noble gases by using the semiautomatic vial sampler panel to obtain a grab sample. To draw a sample, a serum bottle is inserted into a sample chamber, the
sample lines are evacuated, and a solenoid-operated sample valve is opened to allow off gas to enter the bottle. The bottle is then removed and the sample is analyzed in the counting room with a multichannel gamma pulse height analyzer to determine the
concentration of the various noble gas radionuclides. A correlation between the observed activity and the monitor reading
permits calibration of the monitor.
11.5.2.2.3 Off Gas Post-Treatment Radiation Monitoring System
This system monitors radioactivity in the off gas piping downstream of the off gas system charcoal adsorbers and upstream of the off gas system discharge valve. A continuous sample is
extracted from the off gas system piping, passed through the off
gas post-treatment sample panel for monitoring and sampling, and returned to the off gas system piping. The sample panel has a pair of filters (one for particulate collection and one for halogen collection) in parallel (with respect to flow) with two
identical continuous gross radiation detection assemblies. Each
gross radiation assembly consists of a shielded chamber, a set of GM tubes, and a check source. Two radiation monitors analyze and
visually display in the main control room the measured gross
radiation level.
The sample panel shielded chambers can be purged with room air to check detector response to background radiation by using a
three-way solenoid valve operated from the main control room. The sample panel measures and indicates sample line flow. A solenoid-operated check source for each detection assembly
operated from the main control room can be used to check
operability of the gross radiation channel.
Power is supplied from 125-V dc bus A for one radiation monitor, 125-V dc bus B for the other radiation monitors and a common two point recorder, and from a 120-V ac local bus for the sample panel. 16 Each radiation monitor has four trip circuits: three upscale (high-high-high\inop, high-high, and high), one downscale (low).
Each trip is visually displayed on the radiation monitor. The three trips actuate corresponding main control room annunciators:
off gas post-treatment high-high-high radiation\inop, off gas
post-treatment high radiation, and off gas post-treatment
downscale. The fourth trip circuit actuates an off gas post treatment high-high radiation annunciator. High or low sample flow measured at the sample panel actuates a main control room off
gas posttreat sample high-low flow annunciator.
16 RBS USAR Revision 22 11.5-14 8 11.5.2.3 Calibration, Maintenance, and Inspection
Calibration, maintenance, and inspection is performed in accordance
with the plant technical requirements.
8 11.5.2.3.1 Inspection and Tests
During reactor operation, daily checks of system operability are made by observing channel behavior. At periodic intervals during reactor operation, the detector response (of each monitor provided
with a remotely positioned check source) is recorded together with the instrument background count rate to ensure proper functioning of the monitors. Any detector whose response cannot be verified by
observation during normal operation or by using the remotely positioned check source has its response checked with a portable check source. A record is maintained showing the background
radiation level and the detector response.
The system has electronic testing and calibrating equipment which permits channel testing without relocating or dismounting channel components. An internal trip test circuit, adjustable over the full range of the readout meter, is used for testing. Each channel is tested at least semiannually prior to performing a calibration check. Verification of valve operation, ventilation diversion, or other trip functions is done at this time if it can be done without
jeopardizing the plant safety. The tests are documented.
11.5.2.3.2 Calibration 16 The continuous radiation monitor's calibration is traceable to certified National Institute of Standards and Technology and is
accurate to at least 15 percent. The source-detector geometry during primary calibration is identical to the sample-detector
geometry in actual use. Secondary standards which were counted in reproducible geometry during the primary calibration are supplied with each continuous monitor for calibration after installation.
Each continuous monitor is calibrated periodically. A calibration can also be performed by using liquid or gaseous radionuclide standards or by analyzing particulate, iodine, or gaseous grab
samples with laboratory instruments.
11.5.2.3.3 Maintenance
The channel detector, electronics, and recorder are serviced and maintained on a periodic basis or in accordance with manufacturers' recommendations to ensure reliable operations. Such maintenance
includes cleaning, and any required mechanical maintenance of the recorder in addition to the replacement or adjustment of any components required after performing a test or calibration check.
If any work is performed which would affect the calibration, a
recalibration is performed at the completion of the work.
16 RBSUSARRevision12 11.5-15December199911.5.2.4SamplingSection9.3.2discussesvariousprocessandeffluentsamplesperiodicallytakenforchemicalandradiochemicalanalysis.8Liquidprocessandeffluentsamplesareperiodicallytakenandmonitoredforradioactivity.Thoseprovisionsforsamplingnot coveredinSection9.3.2,aredescribedintheindividualsystem designsections.Samplingofthesefluidsystemsisvialocal samplingconnections.Thetechnicalrequirementsdescribe variousliquideffluentsamplingandanalysesfrequencies.
8Additionally,theprocessandeffluentradiologicalmonitoringsystemconsistsofperiodicventilationsamples.Section 11.5.2.1describestheventilationsamplesmonitoredforairborne radioactivitybytheventilationsampleparticulateandgas monitors.Inadditiontotheprogrammedsamplingofvarious ventilationsystems,theventilationsampleparticulateandgas monitors(Section11.5.2.1)areusedtolocatemanuallya specificsourceofhighairborneradioactivitywhenacontinuous radiologicalmonitorsignalsahighradioactivityalarminthe maincontrolroom.Tritiumintheplantareasisdeterminedon thebasisofarepresentativegrabsamplecollectedfromthe ventilationexhaustducts.Grabsamplesareobtainedfrom locationsindicatedinTable11.5-2.Samplesareanalyzedinthe ChemistryLaboratory.Adiscussionofthepost-accidentsampling systemdesignisprovidedinSection9.3.2.6.11.5.3EffluentMonitoringandSampling9Allpotentiallyradioactivegaseousandselectedliquideffluentdischargepathsarecontinuouslymonitoredforradiationlevelas describedinSection11.5.2.Solidwasteshippingcontainersare monitoredwithgammasensitiveportablesurveyinstruments.The followinggaseouseffluentpathsaresampledandmonitored:
91.Mainplantexhaustduct2.Radwastebuildingventilationexhaust
- 3. Fuelbuildingventilationexhaust.12Thefollowingliquideffluentpathissampledandmonitored:1.Liquidradwastesystemeffluent 12AllmonitorrangesarelistedinTable11.5-1.Anisotopicanalysisisperformedperiodicallyonsamplesobtainedfromeacheffluentreleasepathinordertoverifythe adequacyofeffluentprocessingtomeetthedischargelimitsto unrestrictedareas.
RBSUSARRevision15 11.5-16May200215Thiseffluentmonitoringandsamplingprogramisofsuchacomprehensivenatureastoprovidetheinformationforthe effluentmeasuringandreportingprogramsrequiredby 10CFR50Section36a,AppendixA,GeneralDesignCriterion 64,andAppendixIandRegulatoryGuide1.21inannual reportstotheNRC.
1511.5.4ProcessMonitoringandSampling11.5.4.1ImplementationofGeneralDesignCriterion60 Allpotentiallysignificantradioactivedischargepathsareequippedwithacontrolsystemtoisolatethedischarge automaticallyonindicationofahighradiationlevel.
Theseinclude:1.Offgaspost-treatment2.Containmentnormalpurgeexhaust 3.Annulusbuildingventilationexhaust 4.Fuelbuildingventilationexhaust 5.Liquidradwasteeffluent.TheeffluentisolationfunctionsforeachmonitoraregiveninTable11.5-1andinSection11.5.2.11.5.4.2ImplementationofGeneralDesignCriterion639Radiationlevelsinradioactiveandselectedpotentiallyradioactiveprocessstreamsaremonitoredbytheprocessand effluentmonitorsgiveninTable11.5-1.
9Airborneradioactivityinthefuelhandlingareaisdetectedbythefuelbuildingventilationexhaustmonitorswhich initiatethefuelbuildingventilationsystemonhigh radioactivity.Airborneradioactivityinthecontainmentis detectedbythecontainmentanddrywellatmospheremonitors andthecontainmentpurgemonitorwhichisolatethe containmentnormalpurgeonhighradioactivity.These monitorsarealsodescribedinSection12.3.4sincetheyare usedtomonitorin-plantairborneradioactivitytoprotect theworkers.Thearearadiationmonitorsdescribedin Section12.3.4detectabnormalradiationlevelsinthe variousplantareas.Batchreleasesaresampledandanalyzedpriortodischargeinadditiontothecontinuouseffluentmonitoring.The recirculationpumpsforliquidwastetanksarecapableof recirculatingthetankvolumestwicein8hr.
APPENDIX11A
SUMMARY
OFANNUALRADIATIONDOSES RBSUSARAPPENDIX11ALISTOFTABLES 11A-iAugust1987 TableNumberTitle 11A-1ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE ADULTGROUPFROMLIQUIDEFFLUENTS 11A-2ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE TEENGROUPFROMLIQUIDEFFLUENTS 11A-3ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE CHILDGROUPFROMLIQUIDEFFLUENTS 11A-4ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE INFANTGROUPFROMLIQUIDEFFLUENTS 11A-5ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE ADULTGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE2.0KMNWCOWPASTURE1.3KMNNW ANNUALDOSE(MREM/YR)PERUNIT) 11A-6ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE TEENGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE2.0KMNWCOWPASTURE1.3KMNNW ANNUALDOSE(MREM/YR)PERUNIT) 11A-7ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE CHILDGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE2.0KMNWCOWPASTURE1.3KMNNW ANNUALDOSE(MREM/YR)PERUNIT) 11A-8ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE INFANTGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE2.0KMNWCOWPASTURE1.3KMNNW ANNUALDOSE(MREM/YR)PERUNIT) 11A-9ANNUALDOSESTOMAXIMUMINDIVIDUALINTHE ADULTGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE1,260MNWCOWPASTURE1,260MNW ANNUALDOSE(MREM/YR)PERUNIT)
RBSUSARLISTOFTABLES(Cont) 11A-iiAugust198711A-10ANNUALDOSESTOMAXIMUMINDIVIDUALINTHETEENGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTS (RESIDENCE1,260MNWCOWPASTURE1,260MNW ANNUALDOSE(MREM/YR)PERUNIT)11A-11ANNUALDOSESTOMAXIMUMINDIVIDUALINTHECHILDGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE1,260MNWCOWPASTURE1,260MNW ANNUALDOSE(MREM/YR)PERUNIT)11A-12ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEINFANTGROUPFROMGASEOUSRADIOIODINEAND PARTICULATEEFFLUENTS (RESIDENCE1,260MNWANNUALDOSE(MREM/YR)
PERUNIT)11A-13ANNUALDOSESFROMNOBLEGASRELEASESPERUNIT11A-14COMPARISONOFMAXIMUMINDIVIDUALDOSECOMMITMENTSWITHAPPENDIXITO10CFRPART5011A-15CALCULATEDPOPULATIONDOSECOMMITMENT RBSUSARAPPENDIX11A
SUMMARY
OFANNUALRADIATIONDOSESRevision14 11A-1September200114Thevaluespresentedinthisappendixarebasedondatacurrentatthetimeofplantlicensingexceptasnoted.ThecalculatedannualradiationdosestothemaximumindividualfromliquidandgaseouspathwaysarepresentedinTables11A-1 through11A-13.Table11A-14demonstratesthatthecalculated annualradiationdosesarebelowthedesignobjectivesof 10CFR50,AppendixI.Themaximumcalculatedorgandoseperreactorforanindividualfromgaseousreleases(particulatesandradioiodines)is 14.1mrem/yrtoaninfantthyroid.Thisrepresentsa hypotheticalsituationofaninfantwhoresidesatalocationof 2.0kmfromthesiteinthenorthwestdirectionandwhoobtains alloftheirmilkfromacowgrazing1.3kmnorth-northwestof thefacility.
14Thecalculatedexternalexposuretothetotalbodyandskinfrom immersioninnoblegasesis1.7and4.0mrem/yr,respectively.
Theserepresentanindividualresidingatalocation1,260m fromthesiteinthenorthwestdirection.Themaximum calculatedbetaandgammaairdosesfromnoblegasreleasesare 6.6and7.0mrad/yr,respectively.Thiswascalculatedatthe maximumX/Qlocationattherestrictedareaboundary976mfrom thesiteinthewestdirection.Forliquidreleases,itwasassumedthatthemaximumindividualobtainsdrinkingwaterfromtheclosestdownstreampublicwater supply-PeoplesWaterServiceCompany(RiverMile175.5)from theStation.Themaximumindividualwasassumedtoconsumefish andduckswhoseprinciplehabitatistheedgeoftheinitial mixingzone(EIMZ).Thislocationwasalsoconservativelyused incalculatingdosesfromswimmingandboating.Foodproducts obtainedfromtheindividual'sgardenwereassumedtobe irrigatedwithwatertakenfromthenearestpublicwatersupply atarateequaltotheaverageannualrainfall.Thecalculated dosesfromshoreline(recreationwereperformedforthe shoreline)locationnearesttotheEIMZ.Themaximumcalculated totalbodydoseforanindividualfromliquidpathwaysis 0.022mrem/yrintheadultagegroup,andthemaximumcalculated organdoseforanindividualfromliquidpathwaysis0.800 mrem/yrtoachild'sthyroid.Thesedoseswereprimarilydueto fishconsumption.
RBSUSAR 11A-2August1987Thecalculatedannualgaseousandliquiddosesforthepopulationresidingwithina50-miradiusofthesitearepresentedinTable 11A-15.Fortheliquideffluents,thecalculatedpopulationdose commitmentswithin50mifortotalbodyandthyroidare0.44and 0.068manrem/yr,respectively.Forthegaseouseffluents,the calculatedpopulationdosecommitmentswithin50mifromnoblegas effluentsandradioiodinesandparticulatesare1.8manrem/yrtotal bodyand4.1manrem/yrthyroid.Thesedoseswerecalculatedfora projectedpopulationintheyear2010of1,163,282peoplewithin50mi ofthesite.
TABLE11A-1ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEADULTGROUPFROMLIQUIDEFFLUENTSMaximumIndividualLiquidPathwaysAnnualDose(mrem/yr)
Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractPotablewater 4.2-05 0.01.1-054.6-052.1-043.8-053.3-053.5-05Fishconsumption 1.5-02 0.05.7-022.2-027.2-011.2-023.5-032.4-02Invrt.consumption 5.5-03 0.01.4-021.5-024.3-024.6-031.9-034.1-02Shorelinerecreation 1.3-031.5-031.3-031.3-031.3-031.3-031.3-031.3-03Freshvegetation 8.0-06 0.05.6-069.9-062.9-055.3-063.6-063.0-06Storedvegetation 6.3-05 0.04.1-057.8-052.4-054.1-052.9-052.6-05Duckconsumption 7.7-05 0.01.7-031.3-042.5-061.2-051.5-062.0-04Swimmingexposure 5.3-057.2-055.3-055.3-055.3-055.3-055.3-055.3-05Boatingexposure 1.7-042.3-041.7-041.7-041.7-041.7-041.7-041.7-04
________________________________________________TOTALDOSE 2.2-021.8-037.4-023.9-027.6-011.8-027.0-036.7-02
NOTE:4.2-05=4.2x10
-51of1August1987 TABLE11A-2ANNUALDOSESTOMAXIMUMINDIVIDUALINTHETEENGROUPFROMLIQUIDEFFLUENTSMaximumIndividualLiquidPathwaysAnnualDose(mrem/yr)
Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractPotablewater 2.8-05 0.01.0-053.6-051.8-043.9-052.4-052.5-05Fishconsumption 1.1-02 0.06.1-022.2-026.8-011.5-023.4-031.9-02Invrt.consumption 4.5-03 0.01.5-021.5-024.1-025.7-032.1-033.0-02Shorelinerecreation 7.2-038.4-037.2-037.2-037.2-037.2-037.2-037.2-03Freshvegetation 4.5-06 0.05.0-068.2-062.3-058.5-062.7-062.3-06Storedvegetation 6.4-05 0.06.8-051.2-043.0-059.3-054.0-053.2-05Duckconsumption 6.2-05 0.01.4-031.0-041.9-068.4-051.4-061.3-04Swimmingexposure 3.0-044.1-043.0-043.0-043.0-043.0-043.0-043.0-04Boatingexposure 1.7-042.3-041.7-041.7-041.7-041.7-041.7-041.7-04
________________________________________________TOTALDOSE 2.3-029.0-038.5-024.5-027.3-012.9-021.3-025.7-02
NOTE:2.8-05=2.8x10
-51of1August1987
_______________________________________TABLE11A-3ANNUALDOSESTOMAXIMUMINDIVIDUALINTHECHILDGROUPFROMLIQUIDEFFLUENTSMaximumIndividualLiquidPathwaysAnnualDose(mrem/yr)
Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractPotablewater 4.9-05 0.02.9-057.0-054.3-045.4-054.6-054.6-05Fishconsumption 7.9-03 0.07.8-022.0-027.5-011.1-022.8-039.1-03Invrt.consumption 4.2-03 0.02.0-021.3-024.7-023.7-031.9-031.6-02Shorelinerecreation 1.5-031.8-031.5-031.5-031.5-031.5-031.5-031.5-03Freshvegetation 3.8-06 0.08.7-061.0-053.4-055.0-063.1-062.5-06Storedvegetation 7.3-05 0.01.6-042.0-044.8-059.3-056.2-054.7-05Duckconsumption 5.8-05 0.01.4-037.6-051.5-065.4-068.5-074.1-05Swimmingexposure 1.9-042.5-041.9-041.9-041.9-041.9-041.9-041.9-04Boatingexposure 9.7-051.3-049.7-059.7-059.7-059.7-059.7-059.7-05
________________________________________________TOTALDOSE 1.4-022.2-031.0-013.5-028.0-011.7-026.6-032.7-02
NOTE:4.9-05=4.9x10
-51of1August1987 TABLE11A-4ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEINFANTGROUPFROMLIQUIDEFFLUENTSMaximumIndividualLiquidPathwaysAnnualDose(mrem/yr)
Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractPotablewater 4.7-05 0.03.1-057.6-056.5-045.4-054.6-054.4-05
_____________________________________________TOTALDOSE 4.7-05 0.03.1-057.6-056.5-045.4-054.6-054.4-05
NOTE:4.7-05=4.7x10
-51of1August1987 TABLE11A-5ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEADULTGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResident2.0kmNWCowPasture1.3kmNNWAnnualDose(mrem/yr)perunit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 1.7-022.0-021.7-021.7-021.7-021.7-021.7-021.7-02 Inhalation 2.0-03 0.04.0-032.4-039.1-022.6-033.2-032.4-03Freshvegetation 6.3-03 0.02.6-026.9-031.8-016.7-035.2-036.3-03Storedvegetation 3.6-02 0.01.6-013.8-023.7-023.4-023.2-023.4-02Cowmilk 4.9-02 0.0 1.7-01 5.8-02 1.2+00 4.8-02 3.4-02 3.8-02TOTALDOSE 1.1-012.0-023.8-011.2-011.5+001.1-019.1-029.8-02
NOTE:1.7-2=1.7x10
-21of1August1987 TABLE11A-6ANNUALDOSESTOMAXIMUMINDIVIDUALINTHETEENGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResident2.0kmNWCowPasture1.3kmNNWAnnualDose(mrem/yr)perunit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 1.7-022.0-021.7-021.7-021.7-021.7-021.7-021.7-02 Inhalation 2.3-03 0.05.7-032.9-031.2-013.3-034.3-032.8-03Freshvegetation 5.5-03 0.02.5-026.3-031.5-013.9-024.9-035.6-03Storedvegetation 5.9-02 0.02.7-016.5-026.2-022.6-015.5-025.6-02Cowmilk 7.8-02 0.0 3.2-01 1.9-01 1.9+00 8.7-02 6.3-02 6.6-02TOTALDOSE 1.6-012.0-026.4-011.9-012.2+004.1-011.4-011.5-01
NOTE:1.7-2=1.7x10
-21of1August1987 TABLE11A-7ANNUALDOSESTOMAXIMUMINDIVIDUALINTHECHILDGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResidence2.0kmNWCowPasture1.3kmNNWAnnualDose(mrem/yr)perUnit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 1.7-022.0-021.7-021.7-021.7-021.7-021.7-021.7-02 Inhalation 2.6-03 0.07.8-033.1-031.5-013.5-034.1-032.6-03Freshvegetation 9.4-03 0.04.5-021.1-022.2-011.0-028.8-039.2-03Storedvegetation 1.4-01 0.06.7-011.5-011.5-011.4-011.3-011.3-01Cowmilk 1.7-01 0.0 7.7-01 2.2-01 3.9+00 1.9-01 1.5-01 1.5-01TOTALDOSE 3.4-012.0-021.5+004.0-014.4+003.6-013.1-013.1-01
NOTE:1.7-2=1.7x10
-21of1August1987 RBSUSARRevision141of1September2001TABLE11A-8ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEINFANTGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTS14Residence2.0kmNWCowPasture1.3kmNNWAnnualDose(mrem/yr)PerUnit PathwayTotalBody Skin Bone Liver Thyroid(b)Kidney Lung GI-TractContaminatedground1.7-02(a)2.0-021.7-021.7-022.5-021.7-021.7-021.7-02 Inhalation 1.8-03 0.05.8-032.4-032.0-012.4-033.1-031.7-03Cowmilk 3.3-01 0.01.5+004.5-011.4+013.7-013.1-013.2-01
________________________________________________TOTALDOSE 3.5-012.0-021.5+004.7-011.4+013.9-013.3-013.4-01 14___________________________________14NOTES:(a)1.7-2=1.7x10
-2(b)Valuesshownhavebeenconservativelyadjustedtoaccountforincreaseddosesthatmayresultfromplantoperationwithhydrogenwaterchemistry.
14 TABLE11A-9ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEADULTGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResidence1,260mNWCowPasture1,260mNWAnnualDose(mrem/yr)perUnit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 5.2-026.1-025.2-025.2-025.2-025.2-025.2-025.2-02 Inhalation 4.9-03 0.09.9-035.9-032.3-016.6-037.9-036.0-03Freshvegetation 1.6-02 0.06.6-021.8-025.2-011.7-021.3-021.6-02Storedvegetation 9.3-02 0.03.9-019.8-029.4-028.5-028.0-028.4-02 Beef 3.6-02 0.0 1.7-01 3.7-02 9.1-02 3.5-02 3.3-02 6.0-02TOTALDOSE 2.0-016.1-026.9-012.1-019.9-012.0-011.9-012.2-01
NOTE:5.2-02=5.2x10
-21of1August1987 TABLE11A-10ANNUALDOSESTOMAXIMUMINDIVIDUALINTHETEENGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResidence1,260mNWCattlePasture1,260mNWAnnualDose(mrem/yr)PerUnit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 5.2-026.1-025.2-025.2-025.2-025.2-025.2-025.2-02 Inhalation 5.8-03 0.01.4-027.2-033.0-018.3-031.1-026.9-03Freshvegetation 1.4-02 0.06.2-021.6-024.3-011.2-011.2-021.4-02Storedvegetation 1.5-01 0.06.8-011.7-011.6-017.5-011.4-011.4-01 Beef 2.9-02 0.01.4-013.1-027.0-025.6-012.8-024.3-02
________________________________________________TOTALDOSE 2.5-016.1-029.5-012.8-011.0+001.5+002.4-012.6-01
NOTE:5.2-02=5.2x10
-21of1August1987 1of1 August 1987TABLE11A-11ANNUALDOSESTOMAXIMUMINDIVIDUALINTHECHILDGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResidence1,260mNWCattlePasture1,260mNWAnnualDose(mrem/yr)PerUnit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 5.2-026.1-025.2-025.2-025.2-025.2-025.2-025.2-02 Inhalation 6.4-03 0.01.9-027.8-033.8-018.7-031.0-026.5-03Freshvegetation 2.4-02 0.01.1-012.8-026.6-012.7-022.2-022.3-02Storedvegetation 3.4-01 0.01.7+003.8-013.7-013.4-013.3-013.3-01 Beef 5.3-02 0.02.6-015.6-021.2-015.4-025.2-026.0-02
________________________________________________TOTALDOSE 4.8-016.1-022.1+005.2-011.6+004.8-014.7-014.7-01
NOTE:5.2-02=5.2x10
-2 TABLE11A-12ANNUALDOSESTOMAXIMUMINDIVIDUALINTHEINFANTGROUPFROMGASEOUSRADIOIODINEANDPARTICULATEEFFLUENTSResidence1,260mNWAnnualDose(mrem/yr)PerUnit Total Pathway Body Skin Bone Liver Thyroid Kidney Lung GI-TractContaminatedground 5.2-026.1-025.2-025.2-025.2-025.2-025.2-025.2-02 Inhalation 4.5-03 0.01.4-025.9-033.5-015.9-037.7-034.3-03
________________________________________________TOTALDOSE 5.7-026.1-026.6-025.8-024.0-015.8-026.0-025.6-02
NOTE:5.2-02=5.2x10
-21of1August1987 RBSUSARTABLE11A-13ANNUALDOSESFROMNOBLEGASRELEASESPERUNIT1OF1August1987TotalBodySkinBetaAirGammaAir Dose (1)Dose (1)Dose (2)Dose (2)Pathway(mrem/yr)(mrem/yr)(mrad/yr)(mrad/yr)Submersion1.7+00 (3)4.0+006.6+007.0+00
________________________
(1)Locationofanalysisisresidence1,260mnorthwestofthesite.
(2)Locationofanalysisis976mwestofthesite(maximumX/Qlocationatrestrictedareaboundary).
(3)1.7+0=1.7x10 0
RBSUSARTABLE11A-14Revision141of1September2001COMPARISONOFMAXIMUMINDIVIDUALDOSECOMMITMENTSWITHAPPENDIXITO10CFRPART50CalculatedDoseSingleUnit RM-50-2DoseCriterion OperationDesignObjectivesNobleGasReleasesBetadoseinair6.6mrad/yr20mrad/yrGammadoseinair7.0mrad/yr10mrad/yrTotal-bodydose1.7mrem/yr5mrem/yrSkindose4.0mrem/yr15mrem/yrLiquidReleases (1)Total-bodydose0.02mrem/yr5mrem/yrOrganDose0.80mrem/yr5mrem/yrIodinesandParticulate Releases (2)14Organdose14.1mrem/yr15mrem/yr 14(1)Theradiologicaldosespresentedinthistablefortheliquidpathwaysarefortwo-unitoperation(blowdownflow=
4,400gpm).Forsingleunitoperation(blowdownflow=
2,200gpm),thedischargevelocitywouldbehalfthetwo-unit value(2.1fps)duetothereducedflowthroughtheoutfallpipe.Theconcentrationofradionuclidesintheblowdownisidenticalforone-andtwo-unitoperation.Thequantityof radionuclidesreleasedtotheriverforone-unitoperation wouldbehalfthetwo-unitvalue.Atthedownstreamlocation ofthenearestdomesticwaterintake,theradionucliderelease isdispersedthroughouttherivercrosssectionatapproximatelyequalconcentration.Riverflowisthemainfactorcausingdilutionatthispoint,andtheradionuclide concentrationsforsingleunitoperationwouldbeabouthalf thetwo-unitvalues.Attheedgeofthemixingzone,dilution isaffectedbybothriverflowanddischargecharacteristics.
Theone-unitconcentrationsattheedgeofthemixingzone willbeapproximatelyequaltothetwo-unitvalues.14 (2)Carbon-14andtritiumhavebeenaddedtothiscategory.
(b)Valuesshownhavebeenconservativelyadjustedtoaccount forincreaseddosesthatmayresultfromplantoperationwith hydrogenwaterchemistry.
14 RIVER BEND STATION UPDATED SAFETY ANALYSIS REPORTCALCULATED POPULATION DOSE COMMITMENT TABLE 11A-15REVISION 14SEPTEMBER 2001 THIS TABLE HAS BEEN DELETED