F.RECc,?Wednesday,July6,2005PartIIIEnvironmentalProtectionAgency40CFRPart51RegionalHazeRegulationsandGuidelinesforBestAvailableRetrofitTechnology(BART)Determinations;FinalRule39156FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsrequirements,Sulfuroxides,Volatileorganiccompounds.Dated:June15,2005.StephenL.Johnson,Administrator.•Forthereasonssetforthinthepreamble,part51ofchapterIoftitle40oftheCodeofFederalRegulationsisamendedasfollows:PART51—REQUIREMENTSFORPREPARATION,ADOPTION,ANDSUBMITrALOFIMPLEMENTATIONPLANS•1.Theauthoritycitationforpart51continuestoreadasfollows:Authority:23U.S.C.101;42U.S.C.7410—7671q.•2.Section51.302isamendedbyrevisingparagraph(c)(4)(iii)toreadasfollows:§51.302Implementationcontrolstrategiesforreasonablyattributablevisibilityimpairment.*****(c)***(4)***(iii)BARTmustbedeterminedforfossil-fuelfiredgeneratingplantshavingatotalgeneratingcapacityinexcessof750megawattspursuantto“GuidelinesforDeterminingBestAvailableRetrofitTechnologyforCoal-firedPowerPlantsandOtherExistingStationaryFacilities”(1980),whichisincorporatedbyreference,exclusiveofappendixEtotheGuidelines,exceptthatoptionsmorestringentthanNSPSmustbeconsidered.EstablishingaBARTemissionlimitationequivalenttotheNSPSlevelofcontrolisnotasufficientbasistoavoidtheanalysisofcontroloptionsrequiredbytheguidelines.ThisdocumentisEPApublicationNo.450/3—80—009bandhasbeenapprovedforincorporationbyreferencebytheDirectoroftheFederalRegisterinaccordancewith5U.S.C.552(a)and1CFRpart51.ItisforsalefromtheU.S.DepartmentofCommerce,NationalTechnicalInformationService,5285PortRoyalRoad,Springfield,Virginia22161.ItisalsoavailableforinspectionfromtheNationalArchivesandRecordsAdministration(NARA).ForinformationontheavailabilityofthismaterialatNARA,call202—741—6030,orgoto:http://www.orchives.gov/federoLregister/index.html.•3,Section51.308isamendedbyrevisingparagraph(Nremovingandreservingparagraph(c),revisingparagraphs(e)(1)(ii),(e)(3),and(e)(4),andaddingparagaphs(e)(5)and(6)toreadasfollows:§51.308Regionalhazeprogramrequirements.*****(b)Whenarethefirstimplementationplansdueundertheregionalhazeprogram?Exceptasprovidedin§51.309(c),eachStateidentifiedin§51.300(b)(3)mustsubmit,fortheentireState,animplementationplanforregionalhazemeetingtherequirementsofparagraphs(d)and(e)ofthissectionnolaterthanDecember17,2007.(c)(Reservedl*****(e)***(i)***(ii)AdeterminationofBARTforeachBART-eligiblesourceintheStatethatemitsanyairpollutantwhichmayreasonablybeanticipatedtocauseorcontributetoanyimpairmentofvisibilityinanymandatoryClassIFederalarea.AllsuchsourcesaresubjecttoBART.(A)ThedeterminationofBARTmustbebasedonananalysisofthebestsystemofcontinuousemissioncontroltechnologyavailableandassociatedemissionreductionsachievableforeachBART-eligiblesourcethatissubjecttoBARTwithintheState.Inthisanalysis,theStatemusttakeintoconsiderationthetechnologyavailable,thecostsofcompliance,theenergyandnonairqualityenvironmentalimpactsofcompliance,anypollutioncontrolequipmentinuseatthesource,theremainingusefullifeofthesource,andthedegreeofimprovementinvisibilitywhichmayreasonablybeanticipatedtoresultfromtheuseofsuchtechnology.(B)ThedeterminationofBARTforfossil-fuelfiredpowerplantshavingatotalgeneratingcapacitygreaterthan750megawattsmustbemadepursuanttotheguidelinesinappendixYofthispart(GuidelinesforBARTDeterminationsUndertheRegionalHazeRule).(C)Exception.AStateisnotrequiredtomakeadeterminationofBARTforSO2orforNOxifaBART-eligiblesourcehasthepotentialtoemitlessthan40tonsperyearofsuchpollutant(s),orforPM10ifaBARTeligiblesourceemitslessthan15tonsperyearofsuchpollutant.*****(3)AStatewhichoptsunder40CFR51.308(e)(2)toimplementanemissionstradingprogramorotheralternativemeasureratherthantorequiresourcessubjecttoBARTtoinstall,operate,andmaintainBARTmaysatisfythefinalstepofthedemonstrationrequiredbythatsectionasfollows:IfthedistributionofemissionsisnotsubstantiallydifferentthanunderBART,andthealternativemeasureresultsingreateremissionreductions,thenthealternativemeasuremaybedeemedtoachievegreaterreasonableprogress.Ifthedistributionofemissionsissignificantlydifferent,theStatemustconductdispersionmodelingtodeterminedifferencesinvisibilitybetweenBARTandthetradingprogramforeachimpactedClassIarea,fortheworstandbest20percentofdays.Themodelingwoulddemonstrate“greaterreasonableprogress”ifbothofthefollowingtwocriteriaaremet:(i)VisibilitydoesnotdeclineinanyClassIarea,and(ii)Thereisanoverallimprovementinvisibility,determinedbycomparingtheaveragedifferencesbetweenBARTandthealternativeoverallaffectedClassIareas.(4)AStatethatoptstoparticipateintheCleanAirInterstateRulecap-andtradeandtradeprogramunderpart96AAA—EEEneednotrequireaffectedBART-eligibleEGU’stoinstall,operate,andmaintainBART.AStatethatchoosesthisoptionmayalsoincludeprovisionsforageographicenhancementtotheprogramtoaddresstherequirementunder§51.302(c)relatedtoBARTforreasonablyattributableimpairmentfromthepollutantscoveredbytheCAIRcap-andtradeprogram.(5)AfteraStatehasmettherequirementsforBARTorimplementedemissionstradingprogramorotheralternativemeasurethatachievesmorereasonableprogressthantheinstallationandoperationofBART,BART-eligiblesourceswillbesubjecttotherequirementsofparagraph(d)ofthissectioninthesamemannerasothersources.(6)AnyBART-eligiblefacilitysubjecttotherequirementunderparagraph(e)ofthissectiontoinstall,operate,andmaintainBARTmayapplytotheAdministratorforanexemptionfromthatrequirement.Anapplicationforanexemptionwillbesubjecttotherequirementsof§51.303(a)(2)—(h).*****•4.AppendixYtoPart51isaddedtoreadasfollows:AppendixYtoPart51—GuidelinesforBARTDeterminationsUndertheRegionalHazeRuleTableofContentsI.IntroductionandOverviewA.Whatisthepurposeoftheguidelines?B.WhatdoestheCAArequiregenerallyforimprovingvisibility?C.WhatistheBARTrequirementintheCAA?0.WhattypesofvisibilityproblemsdoesEPAaddressinitsregulations?FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulations39157B.WhataretheBARTrequirementsinEPA’sregionalhazeregulations?F.Whatisincludedintheguidelines?G.Whoisthetargetaudiencefortheguidelines?H.DoEPAregulationsrequiretheuseoftheseguidelines?II.HowtoIdentifyBART-eligibleSourcesA.WhatarethestepsinidentifyingBARTeligiblesources?1.Step1:IdentifyemissionunitsintheBARTcategories2.Step2:Identifythestart-updatesoftheemissionunits3.Step3:Comparethepotentialemissionstothe250ton/yrcutoff4.Finalstep:IdentifytheemissionunitsandpollutantsthatconstitutetheBARTeligiblesource.III.HowtoIdentifySources‘SubjecttoBART”IV.TheBARTDetermination:AnalysisofBARTOptionsA.WhatfactorsmustIaddressintheBARTAnalysis?B.WhatisthescopeoftheBARTreview?C.HowdoesaBARTreviewrelatetomaximumachievablecontroltechnology(MACT)standardsunderCAAsection112?D.Whatarethefivebasicstepsofacaseby-caseBARTanalysis?1.Step1:HowdoIidentifyallavailableretrofitemissioncontroltechniques?2.Step2:HowdoIdeterminewhethertheoptionsidentifiedinStep1aretechnicallyfeasible?3.Step3:HowdoIevaluatetechnicallyfeasiblealternatives?4.Step4:ForaBARTreview,whatimpactsamIexpectedtocalculateandreport?WhatmethodsdoesEPArecommendfortheimpactsanalyses?a.Impactanalysispart1:howdoIestimatethecostsofcontrol?b.Whatdowemeanbycosteffectiveness?c.HowdoIcalculateaveragecosteffectiveness?d.HowdoIcalculatebaselineemissions?e.HowdoIcalculateincrementalcosteffectiveness?f.WhatotherinformationshouldIprovideinthecostimpactsanalysis?g.Whatotherthingsareimportanttoconsiderinthecostimpactsanalysis?h.Impactanalysispart2:HowshouldIanalyzeandreportenergyimpacts?i.Impactanalysispart3:HowdoIanalyze“non-airqualityenvironmentalimpacts?”j.Impactanalysispart4:Whatareexamplesofnon-airqualityenvironmentalimpacts?k.HowdoItakeintoaccountaproject’s“remainingusefullife”incalculatingcontrolcosts?5.Step5:HowshouldIdeterminevisibilityimpactsintheBARTdetermination?E.HowdoIselectthe“best”alternative,usingtheresultsofSteps1through5?1.Summaryoftheimpactsanalysis2.Selectinga“best”alternative3.Inselectinga“best”alternative,shouldIconsidertheaffordabilityofcontrols?4.SO2limitsforutilityboilers5.NOxlimitsforutilityboilersV.EnforceableLimits/ComplianceDateI.introductionandOverviewA.Whotisthepurposeoftheguidelines?TheCleanAirAct(CAA),insections169Aand169B,containsrequirementsfortheprotectionofvisibilityin156scenicareasacrosstheUnitedStates.TomeettheCAA’srequirements,wepublishedregulationstoprotectagainstaparticulartypeofvisibilityimpairmentknownas“regionalhaze.”Theregionalhazeruleisfoundinthispartat40CFR51.300through51.309.Theseregulationsrequire,in40CFR51.308(e),thatcertaintypesofexistingstationarysourcesofairpollutantsinstallbestavailableretrofittechnology(BART).TheguidelinesaredesignedtohelpStatesandothers(1)identifythosesourcesthatmustcomplywiththeBARTrequirement,and(2)determinethelevelofcontroltechnologythatrepresentsBARTforeachsource.B.WhotdoestheCAArequiregenerollyforimprovingvisibility?Section169AoftheCAA,addedtotheCAAbythe1977amendments,requiresStatestoprotectandimprovevisibilityincertainscenicareasofnationalimportance.Thescenicareasprotectedbysection169Aare“themandatoryClassIFederalAreas***wherevisibilityisanimportantvalue.”Intheseguidelines,werefertotheseas“ClassIareas.”Thereare156ClassIareas,including47nationalparks(underthejurisdictionoftheDepartmentofInterior—NationalParkService),108wildernessareas(underthejurisdictionoftheDepartmentoftheInterior—FishandWildlifeServiceortheDepartmentofAgriculture—U.S.ForestService),andoneInternationalPark(underthejurisdictionoftheRoosevelt-CampobelloInternationalCommission).TheFederalAgencywithjurisdictionoveraparticularClassIareaisreferredtointheCAAastheFederalLandManager.AcompletelistoftheClassIareasiscontainedin40CFR81.401through81.437,andyoucanfindamapoftheClassIareasatthefollowingInternetsite:http://www.epo.gov/ttn/oorpg/tl/fr_notices/clossimp.gif.TheCAAestablishesanationalgoalofeliminatingman-madevisibilityimpairmentfromallClassIareas,Aspartoftheplanforachievingthisgoal,thevisibilityprotectionprovisionsintheCAAmandatethatEPAissueregulationsrequiringthatStatesadoptmeasuresintheirStateimplementationplans(SIPs),includinglong-termstrategies,toprovideforreasonableprogresstowardsthisnationalgoal.TheCAAalsorequiresStatestocoordinatewiththeFederalLandManagersastheydeveloptheirstrategiesforaddressingvisibility.C.WhotistheBARTrequirementintheCAA?1.Undersection169A(b)(2)(A)oftheCAA,StatesmustrequirecertainexistingstationarysourcestoinstallBART.TheBARTprovisionappliesto“majorstationarysources”from26identifiedsourcecategorieswhichhavethepotentialtoemit250tonsperyearormoreofanyairpollutant.TheCAArequiresonlysourceswhichwereputinplaceduringaspecific15-yeartimeintervaltobesubjecttoBART.TheBARTprovisionappliestosourcesthatexistedasofthedateofthe1977CAAamendments(thatis,August7,1977)butwhichhadnotbeeninoperationformorethan15years(thatis,notinoperationasofAugust7,1962).2.TheCAArequiresBARTreviewwhenanysourcemeetingtheabovedescription“emitsanyairpollutantwhichmayreasonablybeanticipatedtocauseorcontributetoanyimpairmentofvisibility”inanyClassIarea.InidentifyingalevelofcontrolasBART,Statesarerequiredbysection169A(g)oftheCAAtoconsider:(a)Thecostsofcompliance,(b)Theenergyandnon-airqualityenvironmentalimpactsofcompliance,(c)Anyexistingpollutioncontroltechnologyinuseatthesource,(d)Theremainingusefullifeofthesource,and(e)ThedegreeofvisibilityimprovementwhichmayreasonablybeanticipatedfromtheuseofBART.3.TheCAAfurtherrequiresStatestomakeBARTemissionlimitationspartoftheirSIPs.AswithanySIPrevision,StatesmustprovideanopportunityforpubliccommentontheBARTdeterminations,andEPA’sactiononanySIPrevisionwillbesubjecttojudicialreview.D.WhottypesofvisibilityproblemsdoesEPAoddressinitsregulotions?I.Weaddressedtheproblemofvisibilityintwophases.In1980,wepublishedregulationsaddressingwhatwetermed“reasonablyattributable”visibilityimpairment.ReasonablyattributablevisibilityimpairmentistheresultofemissionsfromoneorafewsourcesthataregenerallylocatedincloseproximitytoaspecificClassIarea.Theregulationsaddressingreasonablyattributablevisibilityimpairmentarepublishedin40CFR51.300through51.307.2.OnJuly1,1999,weamendedtheseregulationstoaddressthesecond,morecommon,typeofvisibilityimpairmentknownas“regionalhaze.”Regionalhazeistheresultofthecollectivecontributionofmanysourcesoverabroadregion.Theregionalhazeruleslightlymodified40CFR51.300through51.307,includingtheadditionofafewdefinitionsin§51.301,andaddednew§51.308and51.309.E.WhotoretheBARTrequirementsinEPA’sregionolhozeregulotions?1.IntheJuly1,1999rulemaking,weaddedaBARTrequirementforregionalhaze.WeamendedtheBARTrequirementsin2005.YouwillfindtheBARTrequirementsin40CFR51.308(e).Definitionsoftermsusedin40CFR51.308(e)(1)arefoundin40CFR51.301.2.Aswediscussindetailintheseguidelines,theregionalhazerulecodifiesandclarifiestheBARTprovisionsintheCAA.TherulerequiresthatStatesidentifyandlist“BART-eligiblesources,”thatis,thatStatesidentifyandlistthosesourcesthatfallwithinthe26sourcecategories,wereputinplaceduringthe15-yearwindowoftimefrom1962to1977,andhavepotential39158FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsemissionsgreaterthan250tonsperyear.OncetheStatehasidentifiedtheHARTeligiblesources,thenextstepistoidentifythoseHART-eligiblesourcesthatmay“emitanyairpollutantwhichmayreasonablybeanticipatedtocauseorcontributetoanyimpairmentofvisibility.”Undertherule,asourcewhichfitsthisdescriptionis“subjecttoBART.”ForeachsourcesubjecttoBART,40CFR51.308(e)(1)(ii)(A)requiresthatStatesidentifythelevelofcontrolrepresentingHARTafterconsideringthefactorssetoutinCAAsection169A(gJ,asfollows:—StatesmustidentifythebestsystemofcontinuousemissioncontroltechnologyforeachsourcesubjecttoHARTtakingintoaccountthetechnologyavailable,thecostsofcompliance,theenergyandnon-airqualityenvironmentalimpactsofcompliance,anypollutioncontrolequipmentinuseatthesource,theremainingusefullifeofthesource,andthedegreeofvisibilityimprovementthatmaybeexpectedfromavailablecontroltechnology.3.AfteraStatehasidentifiedthelevelofcontrolrepresentingBART(ifany),itmustestablishanemissionlimitrepresentingHARTandmustensurecompliancewiththatrequirementnolaterthan5yearsafterEPAapprovestheSIP.Statesmayestablishdesign,equipment,workpracticeorotheroperationalstandardswhenlimitationsonmeasurementtechnologiesmakeemissionstandardsinfeasible.F.Whatisincludedintheguidelines?1.TheguidelinesprovideaprocessformakingBARTdeterminationsthatStatescanuseinimplementingtheregionalhazeBARTrequirementsonasource-by-sourcebasis,asprovidedin40CFR51.308(e)(1).StatesmustfollowtheguidelinesinmakingHARTdeterminationsonasource-by-sourcebasisfor750megawatt(MW)powerplantsbutarenotrequiredtousetheprocessintheguidelineswhenmakingHARTdeterminationsforothertypesofsources.2.TheHARTanalysisprocess,andthecontentsoftheseguidelines,areasfollows:(a)IdentificationofallBART-eligiblesources.SectionIIoftheseguidelinesoutlinesastep-by-stepprocessforidentifyingHART-eligiblesources.(b)IdentificationofsourcessubjecttoBART.Asnotedabove,sources“subjecttoHART”arethoseHART-eligiblesourceswhich“emitapollutantwhichmayreasonablybeanticipatedtocauseorcontributetoanyimpairmentofvisibilityinanyClassIarea.”WediscussconsiderationsforidentifyingsourcessubjecttoHARTinsectionIIIoftheguidance.(c)TheBARTdeterminotionprocess.ForeachsourcesubjecttoHART,thenextstepistoconductananalysisofemissionscontrolalternatives.Thisstepincludestheidentificationofavailable,technicallyfeasibleretrofittechnologies,andforeachtechnologyidentified,ananalysisofthecostofcompliance,theenergyandnon-airqualityenvironmentalimpacts,andthedegreeofvisibilityimprovementinaffectedClassIareasresultingfromtheuseofthecontroltechnology.AspartoftheHARTanalysis,theStateshouldalsotakeintoaccounttheremainingusefullifeofthesourceandanyexistingcontroltechnologypresentatthesource.Foreachsource,theStatewilldeterminea“bestsystemofcontinuousemissionreduction”baseduponitsevaluationofthesefactors.ProceduresfortheHARTdeterminationsteparedescribedinsectionIVoftheseguidelines.(d)Emissionslimits.Statesmustestablishemissionlimits,includingadeadlineforcompliance,consistentwiththeHARTdeterminationprocessforeachsourcesubjecttoHART.ConsiderationsrelatedtotheselimitsarediscussedinsectionVoftheseguidelines.G.Whoisthetargetaudiencefortheguidelines?1.TheguidelinesarewrittenprimarilyforthebenefitofState,localandTribalagencies,anddescribeaprocessformakingtheHARTdeterminationsandestablishingtheemissionlimitationsthatmustbeincludedintheirSIPsorTribalimplementationplans(TIPs).Throughouttheguidelines,whicharewritteninaquestionandanswerformat,weaskquestions“Howdo***?andanswerwithphrases“youshould**‘,youmust***“The“you”meansaState,localorTribalagencyconductingtheanalysis.Wehaveusedthisformattomaketheguidelinessimplertounderstand,butwerecognizethatStateshavetheauthoritytorequiresourceownerstoassumepartoftheanalyticalburden,andthattherewillbedifferencesinhowthesupportinginformationiscollectedanddocumented.Wealsorecognizethatdatacollection,analysis,andruledevelopmentmaybeperformedbyRegionalPlanningOrganizations,foradoptionwithineachSIPorTIP.2.Thepreambletothe1999regionalhazerulediscussedatlengththeissueofTribalimplementationoftherequirementstosubmitaplantoaddressvisibility.Asexplainedthere,requirementsrelatedtovisibilityareamongtheprogramsforwhichTribesmaybedeterminedeligibleandreceiveauthorizationtoimplementunderthe“TribalAuthorityRule”(“TAR”)(40CFR49.1through49.11).TribesarenotsubjecttothedeadlinesforsubmittingvisibilityimplementationplansandmayuseamodularapproachtoCAAimplementation.WebelievethereareveryfewHART-eligiblesourceslocatedonTriballands.Wheresuchsourcesexist,theaffectedTribemayapplyfordelegationofimplementationauthorityforthisrule,followingtheprocesssetforthintheTAR.H.DoEPAregulationsrequiretheuseoftheseguidelines?Section169A(b)requiresustoissueguidelinesforStatestofollowinestablishingHARTemissionlimitationsforfossil-fuelfiredpowerplantshavingacapacityinexcessof750megawatts.Thisdocumentfulfillsthatrequirement,whichiscodifiedin40CFR51.308(e)(lj(ii)(H).TheguidelinesestablishanapproachtoimplementingtherequirementsoftheHARTprovisionsoftheregionalhazerule;webelievethattheseproceduresandthediscussionoftherequirementsoftheregionalhazeruleandtheCAAshouldbeusefultotheStates.Forsourcesotherthan750MWpowerplants,however,Statesretainthediscretiontoadoptapproachesthatdifferfromtheguidelines.II.HowtoIdentifyBART-EligibleSourcesThissectionprovidesguidelinesonhowtoidentifyHART-eligiblesources.AHARTeligiblesourceisanexistingstationarysourceinanyof26listedcategorieswhichmeetscriteriaforstartupdatesandpotentialemissions.A.WhatarethestepsinidentifyingBARTeligiblesources?Figure1showsthestepsforidentifyingwhetherthesourceisa“HART-eligiblesource:”Step1:IdentifytheemissionunitsintheHARTcategories,Step2:Identifythestart-updatesofthoseemissionunits,andStep3:Comparethepotentialemissionstothe250ton/yrcutoff.Figure1.HowtodeterminewhetherasourceisHART-eligible:Step1:IdentifyemissionunitsintheHARTcategoriesDoestheplantcontainemissionsunitsinoneormoreofthe26sourcecategories?-No-+Stop-4Yes4ProceedtoStep2Step2:Identifythestart-updatesoftheseemissionunitsDoanyoftheseemissionsunitsmeetthefollowingtwotests?InexistenceonAugust7,1977ANDHeganoperationafterAugust7,1962-No-eStop-,Yes-4ProceedtoStep3Step3:Comparethepotentialemissionsfromtheseemissionunitstothe250ton/yrcutoffIdentifythe“stationarysource”thatincludestheemissionunitsyouidentifiedinStep2.AddthecurrentpotentialemissionsfromalltheemissionunitsidentifiedinStepsIand2thatareincludedwithinthe“stationarysource”boundary.Arethepotentialemissionsfromtheseunits250tonsperyearormoreforanyvisibility-impairingpollutant?-No-Stop—,Yes-4Theseemissionsunitscomprisethe“HART-eligiblesource.”1.Step1:IdentifyEmissionUnitsintheHARTCategories1.TheHARTrequirementonlyappliestosourcesinspecificcategorieslistedintheCAA.TheHARTrequirementdoesnotapplytosourcesinothersourcecategories,regardlessoftheiremissions.Thelistedcategoriesare:(1)Fossil-fuelfiredsteamelectricplantsofmorethan250millionHritishthermalunits(HTU)perhourheatinput,(2)Coalcleaningplants(thermaldryers),(3)Kraftpulpmills,(4)Portlandcementplants,(5)Primaryzincsmelters,(6)Ironandsteelmillplants,(7)Primaryaluminumorereductionplants,FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulations39159(8)Primarycoppersmelters,(9)Municipalincineratorscapableofchargingmorethan250tonsofrefuseperday,(10)Hydrofluoric,sulfuric,andnitricacidplants,(II)Petroleumrefineries,(12)Limeplants,(13)Phosphaterockprocessingplants,(14)Cokeovenbatteries,(15)Sulfurrecoveryplants,(16)Carbonblackplants(furnaceprocess),(17)Primaryleadsmelters,(18)Fuelconversionplants,(19)Sinteringplants,(20)Secondarymetalproductionfacilities,(21)Chemicalprocessplants,(22)Fossil-fuelboilersofmorethan250millionBTUsperhourheatinput,(23)Petroleumstorageandtransferfacilitieswithacapacityexceeding300,000barrels,(24)Taconiteoreprocessingfacilities,(25)Classfiberprocessingplants,and(26)Charcoalproductionfacilities.2.Someplantsmayhaveemissionunitsfrommorethanonecategory,andsomeemittingequipmentmayfitintomorethanonecategory.Examplesofthissituationaresulfurrecoveryplantsatpetroleumrefineries,cokeovenbatteriesandsinteringplantsatsteelmills,andchemicalprocessplantsatrefineries.ForStep1,youidentifyalloftheemissionsunitsattheplantthatfitintooneormoreofthelistedcategories.Youdonotidentifyemissionunitsinothercategories.Example:Amineiscollocatedwithanelectricsteamgeneratingplantandacoalcleaningplant.Youwouldidentifyemissionunitsassociatedwiththeelectricsteamgeneratingplantandthecoalcleaningplant,becausetheyarelistedcategories,butnotthemine,becausecoalminingisnotalistedcategory.3.Thecategorytitlesaregenerallyclearindescribingthetypesofequipmenttobelisted.Mostofthecategorytitlesareverybroaddescriptionsthatencompassallemissionunitsassociatedwithaplantsite(forexample,“petroleumrefining”and“kraftpulpmills”).ThissamelistofcategoriesappearsinthePSDregulations.StatesandsourceownersneednotrevisitanyinterpretationsofthelistmadepreviouslyforpurposesofthePSDprogram.Weprovidethefollowingclarificationsforafewofthecategorytitles:(1)“Steamelectricplantsofmorethan250millionBTU/hrheatinput.”Becausethecategoryrefersto“plants,”weinterpretthiscategorytitletomeanthatboilercapacitiesshouldbeaggregatedtodeterminewhetherthe250millionBTU/hrthresholdisreached.Thisdefinitionincludesonlythoseplantsthatgenerateelectricityforsale.Plantsthatcogeneratesteamandelectricityalsofallwithinthedefinitionof“steamelectricplants”.Similarly,combinedcycleturbinesarealsoconsidered“steamelectricplants”becausesuchfacilitiesincorporateheatrecoverysteamgenerators.Simplecycleturbines,incontrast,arenot“steamelectricplants”becausetheseturbinestypicallydonotgeneratesteam,Example:Astationarysourceincludesasteamelectricplantwiththree100millionBTU/hrboilers.Becausetheaggregatecapacityexceeds250millionBTU/hrforthe“plant,”theseboilerswouldbeidentifiedinStep2.(2)“Fossil-fuelboilersofmorethan250millionBTU/hrheatinput.”Weinterpretthiscategorytitletocoveronlythoseboilersthatareindividuallygreaterthan250millionBTU/hr.However,anindividualboilersmallerthan250millionBTU/hrshouldbesubjecttoBARTifitisanintegralpartofaprocessdescriptionataplantthatisinadifferentBARTcategory—forexample,aboilerataKraftpulpmillthat,inadditiontoprovidingsteamormechanicalpower,usesthewasteliquorfromtheprocessasafuel.Ingeneral,iftheprocessusesanybyproductoftheboilerandtheboiler’sfunctionistoservetheprocess,thentheboilerisintegraltotheprocessandshouldbeconsideredtobepartoftheprocessdescriptiod.Also,youshouldconsideramulti-fuelboilertobea“fossil-fuelboiler”ifitburnsanyamountoffossilfuel.YoumaytakefederallyandStateenforceableoperationallimitsintoaccountindeterminingwhetheramuhi-fuelboiler’sfossilfuelcapacityexceeds250millionBtu/hr.(3)‘Petroleumstorageandtransferfacilitieswithacapacityexceeding300,000barrels.”The300,000barrelcutoffreferstototalfacility-widetankcapacityfortanksthatwereputinplacewithinthe1962—1977timeperiod,andincludesgasolineandotherpetroleum-derivedliquids.(4)“Phosphaterockprocessingplants.”Thiscategorydescriptorisbroad,andincludesalltypesofphosphaterockprocessingfacilities,includingelementalphosphorousplantsaswellasfertilizerproductionplants.(5)“Charcoalproductionfacilities.”Weinterpretthiscategorytoincludecharcoalbriquetmanufacturingandactivatedcarbonproduction.(6)“Chemicalprocessplants.”andpharmaceuticalmanufacturing.Consistentwithpastpolicy,weinterpretthecategory“chemicalprocessplants”toincludethosefacilitieswithinthe2-digitStandardIndustrialClassification(SIC)code28.Accordingly,weinterprettheterm“chemicalprocessplants”toincludepharmaceuticalmanufacturingfacilities.(7)“Secondarymetalproduction.”WeinterpretthiscategorytoincludenonferrousmetalfacilitiesincludedwithinSICcode3341,andsecondaryferrousmetalfacilitiesthatwealsoconsidertobeincludedwithinthecategory“ironandsteelmillplants.”(8)“Primaryaluminumorereduction.”Weinterpretthiscategorytoincludethosefacilitiescoveredby40CFR60.190,thenewsourceperformancestandard(NSPS)forprimaryaluminumorereductionplants.Thisdefinitionisalsoconsistentwiththedefinitionat40CFR63.840.2.Step2:IdentifytheStart-UpDatesoftheEmissionUnits1.EmissionsunitslistedunderStepIareBART-eligibleonlyiftheywere“inexistence”onAugust7,1977butwerenot“inoperation”beforeAugust7,1962.Whatdoes“inexistenceonAugust7,1977”mean?2.Theregionalhazeruledefines“inexistence”tomeanthat:“theowneroroperatorhasobtainedallnecessarypreconstructionapprovalsorpermitsrequiredbyFederal,State,orlocalairpollutionemissionsandairqualitylawsorregulationsandeitherhas(1)begun,orcausedtobegin,acontinuousprogramofphysicalon-siteconstructionofthefacilityor(2)enteredintobindingagreementsorcontractualobligations,whichcannotbecanceledormodifiedwithoutsubstantiallosstotheowneroroperator,toundertakeaprogramofconstructionofthefacilitytobecompletedinareasonabletime.”40CFR51.301.Asthisdefinitionisessentiallyidenticaltothedefinitionof“commenceconstruction”asthattermisusedinthePSDregulations,thetwotermsmeanthesamething.See40CFR51.165(a)(1)(xvi)and40CFR52.21(bj(9).Underthisdefinition,anemissionsunitcouldbe“inexistence”evenifitdidnotbeginoperatinguntilseveralyearsafter1977.Example:Theownerofasourceobtainedallnecessarypermitsinearly1977andenteredintobindingconstructionagreementsinJune1977.Actualon-siteconstructionbeganinlate1978,andconstructionwascompletedinmid-1979.ThesourcebeganoperatinginSeptember1979.Theemissionsunitwas“inexistence”asofAugust7,1977.MajorstationarysourceswhichcommencedconstructionAFTERAugust7,1977(i.e.,majorstationarysourceswhichwerenot“inexistence”onAugust7,1977)weresubjecttonewsourcereview(NSR)underthePSDprogram.Thus,theAugust7,1977“inexistence”testisessentiallythesamethingastheidentificationofemissionsunitsthatweregrandfatheredfromtheNSRreviewrequirementsofthe1977CAAamendments.3.SourcesarenotBART-eligibleiftheonlychangeattheplantduringtherelevanttimeperiodwastheadditionofpollutioncontrols.Forexample,iftheonlychangeatacoppersmelterduringthe1962through1977timeperiodwastheadditionofacidplantsforthereductionofSO2emissions,theseemissioncontrolswouldnotbythemselvestriggeraBARTreview.Whatdoes“inoperationbeforeAugust7,1962”mean?AnemissionsunitthatmeetstheAugust7,1977“inexistence”testisnotBART-eligibleifitwasinoperationbeforeAugust7,1962.“Inoperation”isdefinedas“engagedinactivityrelatedtotheprimarydesignfunctionofthesource.”ThismeansthatasourcemusthavebegunactualoperationsbyAugust7,1962tosatisfythistest.Example:Theowneroroperatorenteredintobindingagreementsin1960.Actualonsiteconstructionbeganin1961,andconstructionwascompleteinmid-1962.ThesourcebeganoperatinginSeptember1962.Theemissionsunitwasnot“inoperation”beforeAugust7,1962andisthereforesubjecttoBART.Whatisa“reconstructedsource?’1.UnderanumberofCAAprograms,anexistingsourcewhichiscompletelyor39160FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationssubstantiallyrebuiltistreatedasanewsource,Such“reconstructed”sourcesaretreatedasnewsourcesasofthetimeofthereconstruction.Consistentwiththisoverallapproachtoreconstructions,thedefinitionofDART-eligiblefacility(reflectedindetailinthedefinitionof“existingstationaryfacility”)includesconsiderationofsourcesthatwereinoperationbeforeAugust7,1962,butwerereconstructedduringtheAugust7,1962toAugust7,1977timeperiod.2.Undertheregionalhazeregulationsat40CFR51.301,areconstructionhastakenplaceif“thefixedcapitalcostofthenewcomponentexceeds50percentofthefixedcapitalcostofacomparableentirelynewsource.”Therulealsostatesthat“lalnyfinaldecisionastowhetherreconstructionhasoccurredmustbemadeinaccordancewiththeprovisionsof§560.15(0(1)through(3)ofthistitle.”“[Tjheprovisionsof§560.15(11(1)through(3)”referstothegeneralprovisionsforNewSourcePerformanceStandards(NSPS).Thus,thesamepoliciesandproceduresforidentifyingreconstructed“affectedfacilities”undertheNSPSprogrammustalsobeusedtoidentifyreconstructed“stationarysources”forpurposesoftheBARTrequirement.3.Youshouldidentifyreconstructionsonanemissionsunitbasis,ratherthanonaplantwidebasis.Thatis,youneedtoidentifyonlythereconstructedemissionunitsmeetingthe50percentcostcriterion.YoushouldincludereconstructedemissionunitsinthelistofemissionunitsyouidentifiedinStep1.Youneedconsideraspossiblereconstructionsonlythoseemissionsunitswiththepotentialtoemitmorethan250tonsperyearofanyvisibility-impairingpollutant.4.The“inoperation”and“inexistence”testsapplytoreconstructedsources.IfanemissionsunitwasreconstructedandbeganactualoperationbeforeAugust7,1962,itisnotDART-eligible.Similarly,anyemissionsunitforwbicbareconstruction“commenced”afterAugust7,1977,isnotDART-eligible.HowaremodificationstreatedundertheDARTprovision?1.TheNSPSprogramandthemajorsourceNSRprogrambothcontaintheconceptofmodifications.Ingeneral,tbeterm“modification”referstoanyphysicalchangeorchangeinthemethodofoperationofanemissionsunitthatresultsinanincreaseinemissions.2.TheDARTprovisionintheregionalhazerulecontainsnoexplicittreatmentofmodificationsorhowmodifiedemissionsunits,previouslysubjecttotherequirementtoinstallbestavailablecontroltechnology(DACTj,lowestachievableemissionrate(LAER)controls,and/orNSPSaretreatedundertherule.AstheDARTrequirementsintheCAAdonotappeartoprovideanyexemptionforsourceswhichhavebeenmodifiedsince1977,thebestinterpretationoftheCAAvisibilityprovisionsisthatasubsequentmodificationdoesnotchangeaunit’sconstructiondateforthepurposeofDARTapplicability.Accordingly,ifanemissionsunitbeganoperationbefore1962,itisnotDART-eligibleifitwasmodifiedbetween1962and1977,solongasthemodificationisnotalsoa“reconstruction.”Ontheotherhand,anemissionsunitwhichbeganoperationwithinthe1962—1977timewindow,butwasmodifiedafterAugust7,1977,isDART-eligible.Wenote,however,thatifsuchamodificationwasamajormodificationthatresultedintheinstallationofcontrols,theStatewilltakethisintoaccountduringthereviewprocessandmayfindthatthelevelofcontrolsalreadyinplaceareconsistentwithDART.3.Step3:ComparethePotentialEmissionstothe250Ton/YrCutoffTheresultofSteps1and2willbealistofemissionsunitsatagivenplantsite,includingreconstructedemissionsunits,thatarewithinoneormoreoftheDARTcategoriesandthatwereplacedintooperationwithinthe1962—1977timewindow.Thethirdstepistodeterminewhetherthetotalemissionsrepresentacurrentpotentialtoemitthatisgreaterthan250tonsperyearofanysinglevisibilityimpairingpollutant.Fugitiveemissions,totheextentquantifiable,mustbecounted.Inmostcases,youwilladdthepotentialemissionsfromallemissionunitsonthelistresultingfromStepsIand2.Inafewcases,youmayneedtodeterminewhethertheplantcontainsmorethanone“stationarysource”astheregionalhazeruledefinesthatterm,andasweexplainfurtherbelow.WhatpollutantsshouldIaddress?Visibility-impairingpollutantsincludethefollowing:(1)Sulfurdioxide(SO2),(2)Nitrogenoxides(NOx),and(3)Particulatematter.YoumayusePM10asanindicatorforparticulatematterinthisintialstep.[Notethatwedonotrecommenduseoftotalsuspendedparticulates(TSP)asinindicatorforparticulatematter.]AsemissionsofPM10includethecomponentsofPM2.5asasubset,thereisnoneedtohaveseparate250tonthresholdsforPM10andPM25;250tonsofPM1erepresentsatmost250tonsofPM2.5,andatmost250tonsofanyindividualparticulatespeciessuchaselementalcarbon,crustalmaterial,etc.However,ifyoudeterminethatasourceofparticulatematterisDART-eligible,itwillbeimportanttodistinguishbetweenthefineandcoarseparticlecomponentsofdirectparticulateemissionsintheremainderoftheDARTanalysis,includingforthepurposeofmodelingthesource’simpactonvisibility.Thisisbecausealthoughbothfineandcoarseparticulatemattercontributetovisibilityimpairment,thelong-rangetransportoffineparticlesisofparticularconcernintheformationofregionalhaze.Thus,forexample,airqualitymodelingresultsusedintheDARTdeterminationwillprovideamoreaccuratepredictionofasource’simpactonvisibilityiftheinputsintothemodelaccountfortherelativeparticlesizeofanydirectlyemittedparticulatematter(i.e.PM10vs.PM15).Youshouldexercisejudgmentindecidingwhetherthefollowingpollutantsimpairvisibilityinanarea:(4)Volatileorganiccompounds(VOCj,and(5)Ammoniaandammoniacompounds.YoushoulduseyourbestjudgmentindecidingwhetherVOCorammoniaemissionsfromasourcearelikelytohaveanimpactonvisibilityinanarea.CertaintypesofVOCemissions,forexample,aremorelikelytoformsecondaryorganicaerosolsthanothers.1Similarly,controllingammoniaemissionsinsomeareasmaynothaveasignificantimpactonvisibility.YouneednotprovideaformalshowingofanindividualdecisionthatasourceofVOCorammoniaemissionsisnotsubjecttoDARTreview.DecauseairqualitymodelingmaynotbefeasibleforindividualsourcesofVOCorammonia,youshouldalsoexerciseyourjudgementinassessingthedegreeofvisibilityimpactsduetoemissionsofVOCandemissionsofammoniaorammoniacompounds.YoushouldfullydocumentthebasisforjudgingthataVOCorammoniasourcemeritsDARTreview,includingyourassessmentofthesource’scontributiontovisibilityimpairment.Whatdoestheterm“potential”emissionsmean?Theregionalhazeruledefinespotentialtoemitasfollows:“Potentialtoemit”meansthemaximumcapacityofastationarysourcetoemitapollutantunderitsphysicalandoperationaldesign.Anyphysicaloroperationallimitationonthecapacityofthesourcetoemitapollutantincludingairpollutioncontrolequipmentandrestrictionsonhoursofoperationoronthetypeoramountofmaterialcombusted,stored,orprocessed,shallbetreatedaspartofitsdesignifthelimitationortheeffectitwouldhaveonemissionsisfederallyenforceable.Secondaryemissionsdonotcountindeterminingthepotentialtoemitofastationarysource.Thedefinitionof“potentialtoemit”meansthatasourcewhichactuallyemitslessthan250tonsperyearofavisibility-impairingpollutantisDART-eligibleifitsemissionswouldexceed250tonsperyearwhenoperatingatitsmaximumcapacitygivenitsphysicalandoperationaldesign(andconsideringallfederallyenforceableandStateenforceablepermitlimits.)Example:Asource,whileoperatingatonefourthofitscapacity,emits75tonsperyearofSO2.Ifitwereoperatingat100percentofitsmaximumcapacity,thesourcewouldemit300tonsperyear.Decauseundertheabovedefinitionsuchasourcewouldhave“potential”emissionsthatexceed250tonsperyear,thesource(ifinalistedcategoryandbuiltduringthe1962—1977timewindow)wouldbeDART-eligible.HowdoIidentifywhetheraplanthasmorethanone“stationarysource?”1.Theregionalhazerule,in40CFR51.301,definesastationarysourceasa“building,structure,facilityorinstallationwhichemitsormayemitanyairpollutant.”2‘Fineparticles:OverviewofAtmosphericChemistry,SourcesofEmissions,andAmbientMonitoringData,MemorandumtoDocketOAR2002—006,April1,2005.ZNote:Mostofthesetermsanddefinitionsarethesameforregionalhazeandtheioaovisibilityregulations.Fortheregionalhazeruleweusetheterm“DART-eligiblesource”ratherthan“existingstationaryfacility”toclarifythatonlyalimitedsubsetofexistingstationarysourcesaresub]ecttoDART.FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulations39161Therulefurtherdefines“building,structureorfacility’’as:allofthepollutant-emittingactivitieswhichbelongtothesameindustrialgrouping,arelocatedononeormorecontiguousoradjacentproperties,andareunderthecontrolofthesameperson(orpersonsundercommoncontrol).Pollutant-emittingactivitiesmustbeconsideredaspartofthesameindustrialgroupingiftheybelongtothesameMajorGroup(i.e.,whichhavethesametwo-digitcode)asdescribedintheStandardIndustrialClassificationManual,1972asamendedbythe1977Supplement(U.S.GovernmentPrintingOfficestocknumbers4101—0066and003—005—00176—0,respectively).2.Inapplyingthisdefinition,itisnecessarytodeterminewhichfacilitiesarelocatedon“contiguousoradjacentproperties.”Withinthiscontiguousandadjacentarea,itisalsonecessarytogroupthoseemissionunitsthatareunder“commoncontrol.”Wenotethattheseplantboundaryissuesand“commoncontrol”issuesareverysimilartothosealreadyaddressedinimplementationofthetitleVoperatingpermitsprogramandinNSR.3.Foremissionunitswithinthe“contiguousoradjacent”boundaryandundercommoncontrol,youmustgroupemissionunitsthatarewithinthesameindustrialgrouping(thatis,associatedwiththesame2-digitSICcode)inordertodefinethestationarysource.3FormostplantsontheBARTsourcecategorylist,therewillonlybeone2-digitSICthatappliestotheentireplant.Forexample,allemissionunitsassociatedwithkraftpulpmillsarewithinSICcode26,andchemicalprocessplantswillgenerallyincludeemissionunitsthatareallwithinSICcode28.The“2-digitSICtest”appliesinthesamewayasthetestisappliedinthemajorsourceNSRprograms.44.Forpurposesoftheregionalhazerule,youmustgroupemissionsfromallemissionunitsputinplacewithinthe1962—1977timeperiodthatarewithinthe2-digitSICcode,evenifthoseemissionunitsareindifferentcategoriesontheBARTcategorylist.Examples:Achemicalplantwhichstartedoperationswithinthe1962to1977timeperiodmanufactureshydrochloricacid(withinthecategorytitle“Hydrochloric,sulfuric,andnitricacidplants”)andvariousorganicchemicals(withinthecategorytitle“chemicalprocessplants”).AlloftheemissionunitsarewithinSICcode28and,therefore,alltheemissionunitsare3WerecognizethatweareinatransitionperiodfromtheuseoftheSICsystemtoanewsystemcalledtheNorthAmericanIndustryClassificationSystem(NAICS).ForpurposesofidentifyingBARTeligiblesources,youmayuseeither2-digitSICSortheequivalentintheNAtCSsystem.4TheconceptofsupportfacilityusedfortheNSRprogramapplieshereaswell.Supportfacilities,thatisfacilitiesthatconvey,storeorotherwiseassistintheproductionoftheprincipalproduct,mustbegroupedwithprimaryfacilitiesevenwhenthefacilitiesfallwihinseparateSICcodes.ForpurposesofBARTreviews,however,suchsupportfacilitiesIa)mustbewithinoneofthe26listedsourcecategoriesandIb)musthavebeeninexistenceasofAugust7,1977,and(c)mustnothavebeeninoperationasofAugust7,1962.consideredindeterminingBARTeligibilityoftheplant.Yousumtheemissionsoveralloftheseemissionunitstoseewhethertherearemorethan250tonsperyearofpotentialemissions.Asteelmillwhichstartedoperationswithinthe1962to1977timeperiodincludesasinteringplant,acokeovenbattery,andvariousotheremissionunits.AlloftheemissionunitsarewithinSICcode33.Yousumtheemissionsoveralloftheseemissionunitstoseewhethertherearemorethan250tonsperyearofpotentialemissions.4.FinalStep:IdentifytheEmissionsUnitsandPollutantsThatConstitutetheBARTEligibleSourceIftheemissionsfromthelistofemissionsunitsatastationarysourceexceedapotentialtoemitof250tonsperyearforanyvisibilityimpairingpollutant,thenthatcollectionofemissionsunitsisaBART-eligiblesource.Example:Astationarysourcecomprisesthefollowingtwoemissionsunits,withthefollowingpotentialemissions:EmissionsunitA200tons/yrSOa150tons/yrNOx25tons/yrPMEmissionsunitB100tons/yrSO275tons/yrNOx10tons/yrPMForthisexample,potentialemissionsofSO2are300tons/yr.whichexceedsthe250tons/yrthreshold.Accordingly,theentire“stationarysource”,thatis,emissionsunitsAandB,maybesubjecttoaBARTreviewforSO2,NOx,andPM,eventhoughthepotentialemissionsofPMandNOxateachemissionsunitarelessthan250tons/yreach.Example:Thetotalpotentialemissions,obtainedbyaddingthepotentialemissionsofallemissionunitsinalistedcategoryataplantsite,areasfollows:200tons/yrSO2150tons/yrNOx25tons/yrPMEventhoughtotalemissionsexceed250tons/yr,noindividualregulatedpollutantexceeds250tons/yrandthissourceisnotBART-eligible.CanStatesestablishdeminimislevelsofemissionsforpollutantsatBART-eligiblesources?InordertosimplifyBARTdeterminations,StatesmaychoosetoidentifydeminimislevelsofpollutantsatBART-eligiblesources(butarenotrequiredtodoso).Deminimisvaluesshouldbeidentifiedwiththepurposeofexcludingonlythoseemissionssominimalthattheyareunlikelytocontributetoregionalhaze.AnydeminimisvaluesthatyouadoptmustnotbehigherthanthePSDapplicabilitylevels:40tons/yrforSOandNOxand15tons/yrforPMie.Thesedeminimislevelsmayonlybeappliedonaplant-widebasis.III.HowtoIdentifySources“SubjecttoBART”OnceyouhavecompiledyourlistofBART-eligiblesources,youneedtodeterminewhether(1)tomakeBARTdeterminationsforallofthemor(2)toconsiderexemptingsomeofthemfromBARTbecausetheymaynotreasonablybeanticipatedtocauseorcontributetoanyvisibilityimpairmentinaClassIarea.IfyoudecidetomakeBARTdeterminationsforalltheBART-eligiblesourcesonyourlist,youshouldworkwithyourregionalplanningorganization(RPO)toshowthat,collectively,theycauseorcontributetovisibilityimpairmentinatleastoneClassIarea.YoushouldthenmakeindividualBARTdeterminationsbyapplyingthefivestatutoryfactorsdiscussedinSectionIVbelow.Ontheotherhand,youalsomaychoosetoperformaninitialexaminationtodeterminewhetheraparticularBART-eligiblesourceorgroupofsourcescausesorcontributestovisibilityimpairmentinnearbyClassIareas.Ifyouranalysis,orinformationsubmittedbythesource,showsthatanindividualsourceorgroupofsources(orcertainpollutantsfromthosesources)isnotreasonablyanticipatedtocauseorcontributetoanyvisibilityimpairmentinaClassIarea,thenyoudonotneedtomakeBARTdeterminationsforthatsourceorgroupofsources(orforcertainpollutantsfromthosesources).Insuchacase,thesourceisnot“subjecttoBART”andyoudonotneedtoapplythefivestatutoryfactorstomakeaBARTdetermination.ThissectionoftheGuidelinediscussesseveralapproachesthatyoucanusetoexemptsourcesfromtheBARTdeterminationprocess.A.WhatStepsDoIFollowToDetermineWhetheraSourceorGroupofSourcesCauseorCantributetoVisibilityImpairmentforPurposesofRAPT?1.HowDoIEstablishaThreshold?OneofthefirststepsindeterminingwhethersourcescauseorcontributetovisibilityimpairmentforpurposesofBARTistoestablishathreshold(measuredindeciviews)againstwhichtomeasurethevisibilityimpactofoneormoresources.Asinglesourcethatisresponsiblefora1.0deciviewchangeormoreshouldbeconsideredto“cause”visibilityimpairment;asourcethatcauseslessthana1.0deciviewchangemaystillcontributetovisibilityimpairmentendthusbesubjecttoBART.BecauseofvaryingcircumstancesaffectingdifferentClassIareas,theappropriatethresholdfordeterminingwhetherasource“contributestoanyvisibilityimpairment”forthepurposesofBARTmayreasonablydifferacrossStates.Asageneralmatter,anythresholdthatyouusefordeterminingwhetherasource“contributes”tovisibilityimpairmentshouldnotbehigherthan0.5deciviews.Insettingathresholdfor“contribution,”youshouldconsiderthenumberofemissionssourcesaffectingtheClassIareasatissueandthemagnitudeoftheindividualsources’impacts.5Ingeneral,alargernumberofsourcescausingimpactsinaClassIareamaywarrantalowercontributionthreshold.Statesremainfreetouseathresholdlowerthan0.5deciviewsiftheyconcludethattheWeexpectthetregionalplanningorganizationswilthavemodelinginformationthatidentifiessourcesaffectingvisibilityinindividualclassIareas.39162FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationslocationofalargenumberofBART-eligiblesourceswithintheStateandinproximitytoaClassIareajustifythisapproach.2.WhatPollutantsDoINeedtoConsider?YoumustlookatSO2,NOx,anddirectparticulatematter(PM)emissionsindeterminingwhethersourcescauseorcontributetovisibilityimpairment,includingbothPM10andPM25.ConsistentwiththeapproachforidentifyingyourHART-eligiblesources,youdonotneedtoconsiderlessthandeminimisemissionsofthesepollutantsfromasource.AsexplainedinsectionII,youmustuseyourbestjudgementtodeterminewhetherVOCorammoniaemissionsarelikelytohaveanimpactonvisibilityinanarea.Inaddition,althoughasexplainedinSectionII,youmayusePM10anindicatorforparticulatematterindeterminingwhetherasourceisHART-eligible,indeterminingwhetherasourcecontributestovisibilityimpairment,youshoulddistinguishbetweenthefineandcoarseparticlecomponentsofdirectparticulateemissions.Althoughbothfineandcoarseparticulatemattercontributetovisibilityimpairment,thelong-rangetransportoffineparticlesisofparticularconcernintheformationofregionalhaze.AirqualitymodelingresultsusedintheHARTdeterminationwillprovideamoreaccuratepredictionofasource’simpactonvisibilityiftheinputsintothemodelaccountfortherelativeparticlesizeofanydirectlyemittedparticulatematter(i.e.PM10vs.PM25).3.WhatKindofModelingShouldIUseToDetermineWhichSourcesandPollutantsNeedNotHeSubjecttoHART?ThissectionpresentsseveraloptionsfordeterminingthatcertainsourcesneednotbesubjecttoHART.Theseoptionsrelyondifferentmodelingand/oremissionsanalysisapproaches.Theyareprovidedforyourguidance.Youmayalsouseotherreasonableapproachesforanalyzingthevisibilityimpactsofanindividualsourceorgroupofsources.Option1:IndividuolSourceAttributionApprooch(DispersionModeling)YoucanusedispersionmodelingtodeterminethatanindividualsourcecannotreasonablybeanticipatedtocauseorcontributetovisibilityimpairmentinaClassIareaandthusisnotsubjecttoHART.Underthisoption,youcananalyzeanindividualsource’simpactonvisibilityasaresultofitsemissionsofSO2,NOxanddirectPMemissions.Dispersionmodelingcannotcurrentlybeusedtoestimatethepredictedimpactsonvisibilityfromanindividualsource’semissionsofVOCorammonia.Youmayuseamorequalitativeassessmenttodetermineonacase-by-casebasiswhichsourcesofVOCorammoniaemissionsmaybelikelytoimpairvisibilityandshouldNotethatthecontributionthresholdshouldbeusedtodeterminewhetheranindividualsourceisreasonablyanticipatedtocontributetovisibilityimpairment.Youshouldnotaggregatethevisibilityeffectsofmultiplesourcesandcomparetheircollectiveeffectsagainstyourcontrihutionthresholdbecausethiswouldinappropriatelycreatea“contributetocontribution”test.thereforebesubjecttoHARTreview,asexplainedinsectionII.A.3.above.YoucanuseCALPUFForotherappropriatemodeltopredictthevisibilityimpactsfromasinglesourceataClassIarea.CALPUFFisthebestregulatorymodelingapplicationcurrentlyavailableforpredictingasinglesource’scontributiontovisibilityimpairmentandiscurrentlytheonlyEPAapprovedmodelforuseinestimatingsinglesourcepollutantconcentrationsresultingfromthelongrangetransportofprimarypollutants.Itcanalsobeusedforsomeotherpurposes,suchasthevisibilityassessmentsaddressedintoday’srule,toaccountforthechemicaltransformationofSO2andNOx.Thereareseveralstepsformakinganindividualsourceattributionusingadispersionmodel:1.Developomodelingprotocol.Somecriticalitemstoincludeintheprotocolarethemeteorologicalandterraindatathatwillbeused,aswellasthesource-specificinformation(stackheight,temperature,exitvelocity,elevation,andemissionratesofapplicablepollutants)andreceptordatafromappropriateClassIareas.WerecommendfollowingEPA’sInteragencyWorkgrouponAirQualityModeling(IWAQM)Phose2SummoryReportondRecommendationsforModelingLongRangeTransportImpacts9forparametersettingsandmeteorologicaldatainputs.YoumayuseothersettingsfromthoseinIWAQM,butyoushouldidentifythesesettingsandexplainyourselectionofthesesettings.Oneimportantelementoftheprotocolisinestablishingthereceptorsthatwillbeusedinthemodel.ThereceptorsthatyouuseshouldbelocatedinthenearestClassIareawithsufficientdensitytoidentifythelikelyvisibilityeffectsofthesource.ForotherClassIareasinrelativelycloseproximitytoaBART-eligiblesource,youmaymodelafewstrategicreceptorstodeterminewhethereffectsatthoseareasmaybegreaterthanatthenearestClassIarea.Forexample,youmightchosetolocatereceptorsattheseareasattheclosestpointtothesource,atthehighestandlowestelevationintheClassIarea,attheIMPROVEmonitor,andattheapproximateexpectedplumereleaseheight.IfthehighestmodeledeffectsareobservedatthenearestClassIarea,youmaychoosenottoanalyzetheotherClassIareasanyfurtherasadditionalanalysesmightbeunwarranted.YoushouldbearinmindthatsomereceptorswithintherelevantClassIareamaybelessthan50kmfromthesourcewhileotherreceptorswithinthatsameClassIareamaybegreaterthan50lanfromthesame7Themodelcodeanditsdocumentationareavailableatnocostfordownloadfromhttp:/Iwww.epa.govlscram001/tt22.htm#colpuffTheGuidelineonAirQualityModels,40CFRpart51,appendixW,addressestheregulatoryapplicationofairqualitymodelsforassessingcriteriapollutantsundertheCAA,anddescribesfurthertheproceduresforusingtheCALPUFFmodel,aswellasforobtainingapprovalfortheuseofother,nonguidelinemodels.9lntemgencyWorkgrouponAirQualityModeling[IWAQM)Phase2SummaiyReportandRecommendationsforModelingLangRangeTransportImpacts,U.S.EnvironmentalProtectionAgency,EPA—454/R—98—019,Oecember1998.source.AsindicatedbytheGuidelineonAirQualityModels,40CFRpart51,appendixW,thissituationmaycallfortheuseoftwodifferentmodelingapproachesforthesameClassIareaandsource,dependingupontheState’schosenmethodformodelingsourceslessthan50km.Insituationswhereyouareassessingvisibilityimpactsforsourcereceptordistanceslessthan50km,youshoulduseexpertmodelingjudgmentindeterminingvisibilityimpacts,givingconsiderationtobothCALPUFFandotherappropriatemethods.Indevelopingyourmodelingprotocol,youmaywanttoconsultwithEPAandyourregionalplanningorganization(RPO).Upfrontconsultationwillensurethatkeytechnicalissuesareaddressedbeforeyouconductyourmodeling.2.Withtheacceptedprotocolandcamparethepredictedvisibilityimpactswithyourthresholdfor“contribution.”Youshouldcalculatedailyvisibilityvaluesforeachreceptorasthechangeindeciviewscomparedagainstnaturalvisibilityconditions.YoucanuseEPA’s“GuidanceforEstimatingNaturalVisibilityConditionsUndertheRegionalHazeRule,”EPA—454/B—03—005(September2003)inmakingthiscalculation.TodeterminewhetherasourcemayreasonablybeanticipatedtocauseorcontributetovisibilityimpairmentatClassIarea,youthencomparetheimpactspredictedbythemodelagainstthethresholdthatyouhaveselected.Theemissionsestimatesusedinthemodelsareintendedtoreflectsteady-stateoperatingconditionsduringperiodsofhighcapacityutilization.Wedonotgenerallyrecommendthatemissionsreflectingperiodsofstart-up,shutdown,andmalfunctionbeused,assuchemissionratescouldproducehigherthannormaleffectsthanwouldbetypicalofmostfacilities.WerecommendthatStatesusethe24houraverageactualemissionratefromthehighestemittingdayofthemeteorologicalperiodmodeled,unlessthisratereflectsperiodsstart-up,shutdown,ormalfunction.Inaddition,themonthlyaveragerelativehumidityisused,ratherthanthedailyaveragehumidity—anapproachthateffectivelylowersthepeakvaluesindailymodelaverages.Forthesereasons,ifyouusethemodelingapproachwerecommend,youshouldcompareyour“contribution”thresholdagainstthe98thpercentileofvalues.Ifthe98thpercentilevaluefromyourmodelingislessthanyourcontributionthreshold,thenyoumayconcludethatthesourcedoesnotcontributetovisibilityimpairmentandisnotsubjecttoBART.Option2:UseofModelPlantsTaExemptIndividualSourcesWithCommonCharacteristicsUnderthisoption,analysesofmodelplantscouldbeusedtoexemptcertainHART-eligiblesourcesthatsharespecificcharacteristics.ItmaybemostusefultousethistypeofanalysistoidentifythetypesofsmallsourcesthatdonotcauseorcontributetovisibilityimpairmentforpurposesofBART,andthusshouldnotbesubjecttoaBARTreview.DifferentClassIareasmayhavedifferentcharacteristics,however,soFederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsyoushouldusecaretoensurethatthecriteriayoudevelopareappropriatefortheapplicablecases.Incarryingoutthisapproach,youcouldusemodelinganalysesofrepresentativeplantstoreflectgroupingsofspecificsourceswithimportantcommoncharacteristics.Basedontheseanalyses,youmayfindthatcertaintypesofsourcesareclearlyanticipatedtocauseorcontributetovisibilityimpairment.YoucouldthenchoosetocategoricallyrequirethosetypesofsourcestoundergoaBARTdetermination.Conversely,youmayfindbasedonrepresentativeplantanalysesthatcertaintypesofsourcesarenotreasonablyanticipatedtocauseorcontributetovisibilityimpairment.Todothis,youmayconductyourownmodelingtoestablishemissionlevelsanddistancesfromClassIareasonwhichyoucanrelytoexemptsourceswiththosecharacteristics.Forexample,basedonyourmodelingyoumightchoosetoexemptallNOx-onlysourcesthatemitlessthanacertainamountperyearandarelocatedacertaindistancefromaClassIarea.YoucouldthenchoosetocategoricallyexemptsuchsourcesfromtheBARTdeterminationprocess.OuranalysesofvisibilityimpactsfrommodelplantsprovideausefulexampleofthetypeofanalysesthatcanbeusedtoexemptcategoriesofsourcesfromBART.1OInouranalyses,wedevelopedmodelplants(EGU5andnon-EGU5),withrepresentativeplumeandstackcharacteristics,foruseinconsideringthevisibilityimpactfromemissionsourcesofdifferentsizesandcompositionsatdistancesof50,100and200kilometersfromtwohypotheticalClassIareas(oneintheEastandoneintheWest).AstheplumeandstackcharacteristicsofthesemodelplantsweredevelopedconsideringthebroadrangeofsourceswithintheECUandnon-ECUcategories,theydonotnecessarilyrepresentanyspecificplant.However,theresultsoftheseanalysesareinstructiveinthedevelopmentofanexemptionprocessforanyClassIarea.Inpreparingouranalyses,wehavemadeanumberofassumptionsandexercisedcertainmodelingchoices;someofthesehaveatendencytolendconservatismtotheresults,overstatingthelikelyeffects,whileothersmayunderstatethelikelyeffects.Onbalance,whenallofthesefactorsareconsidered,webelievethatourexamplesreflectrealistictreatmentsofthesituationsbeingmodeled.Basedonouranalyses,webelievethataStatethathasestablished0.5deciviewsasacontributionthresholdcouldreasonablyexemptfromtheBARTreviewprocesssourcesthatemitlessthan500tonsperyearofNOxor502(orcombinedNOxand502),aslongasthesesourcesarelocatedmorethan50kilometersfromanyClassIarea;andsourcesthatemitlessthan1000tonsperyearofNOxor502(orcombinedNOxand502)thatarelocatedmorethan100kilometersfromanyClassIarea.Youdo,however,havetheoptionofshowingotherthresholdsmightalsobeappropriategivenyourspecificcircumstances.CALPUFFAnalysisinSupportoftheJune2005ChangestotheRegionalHazeRule,U.S.EnvironmentalProtectionAgency,June15,2005,DocketNo.OAR—2002—0076.Option3:GumulotiveModelingToShowThotNoSourcesinoStoteAreSublecttoBARTYoumayalsosubmittoEPAademonstrationbasedonananalysisofoverallvisibilityimpactsthatemissionsfromBARTeligiblesourcesinyourState,consideredtogether,arenotreasonablyanticipatedtocauseorcontributetoanyvisibilityimpairmentinaClassIarea,andthusnosourceshouldbesubjecttoBART.Youmaydothisonapollutantbypollutantbasisorforallvisibility-impairingpollutantstodetermineifemissionsfromthesesourcescontributetovisibilityimpairment.Forexample,emissionsofSO2fromyourBART-eligiblesourcesmayclearlycauseorcontributetovisibilityimpairmentwhiledirectemissionsofPM2.5fromthesesourcesmaynotcontributetoimpairment.Ifyoucanmakesuchademonstration,thenyoumayreasonablyconcludethatnoneofyourBARTeligiblesourcesaresubjecttoBARTforaparticularpollutantorpollutants.Asnotedabove,yourdemonstrationshouldtakeintoaccounttheinteractionsamongpollutantsandtheirresultingimpactsonvisibilitybeforemakinganypollutant-specificdeterminations.Analysesmaybeconductedusingseveralalternativemodelingapproaches.First,youmayusetheCALPUFForotherappropriatemodelasdescribedinOption1toevaluatetheimpactsofindividualsourcesondownwindClassIareas,aggregatingthoseimpactstodeterminethecollectivecontributionofallBART-eligiblesourcestovisibilityimpairment.Youmayalsouseaphotochemicalgridmodel.Asageneralmatter,thelargerthenumberofsourcesbeingmodeled,themoreappropriateitmaybetouseaphotochemicalgridmodel.However,becausesuchmodelsaresignificantlylesssensitivethandispersionmodelstothecontributionsofoneorafewsources,aswellastotheinteractionsamongsourcesthatarewidelydistributedgeographically,ifyouwishtouseagridmodel,youshouldconsultwiththeappropriateEPARegionalOfficetodevelopanappropriatemodelingprotocol.IV.TheBARTDetermination:AnalysisofBARTOptionsThissectiondescribestheprocessfortheanalysisofcontroloptionsforsourcessubjecttoBART.A.WhotfoctorsmustIoddressintheBARTreview?ThevisibilityregulationsdefineBARTasfollows:BestAvoilobleRetrofitTechnology(BART)meansanemissionlimitationbasedonthedegreeofreductionachievablethroughtheapplicationofthebestsystemofcontinuousemissionreductionforeachpollutantwhichisemittedby...[aBART-eligiblesource].Theemissionlimitationmustbeestablished,onacase-by-casebasis,takingintoconsiderationthetechnologyavailable,thecostsofcompliance,theenergyandnon-airqualityenvironmentalimpactsofcompliance,anypollutioncontrolequipmentinuseorinexistenceatthesource,theremainingusefullifeofthesource,andthe39163degreeofimprovementinvisibilitywhichmayreasonablybeanticipatedtoresultfromtheuseofsuchtechnology.TheBARTanalysisidentifiesthebestsystemofcontinuousemissionreductiontakingintoaccount:(1)Theavailableretrofitcontroloptions,(2)Anypollutioncontrolequipmentinuseatthesource(whichaffectstheavailabilityofoptionsandtheirimpacts),(3)Thecostsofcompliancewithcontroloptions,(4)Theremainingusefullifeofthefacility,(5)Theenergyandnon-airqualityenvironmentalimpactsofcontroloptions(6)Thevisibilityimpactsanalysis.B.WhotisthescopeoftheBARTreview?OnceyoudeterminethatasourceissubjecttoBARTforaparticularpollutant,thenforeachaffectedemissionunit,youmustestablishBARTforthatpollutant.TheBARTdeterminationmustaddressairpollutioncontrolmeasuresforeachemissionsunitorpollutantemittingactivitysubjecttoreview.Exompie:Plantwideemissionsfromemissionunitswithinthelistedcategoriesthatbeganoperationwithinthe“timewindow”forBARThare300tons/yrofNOx,200tons/yrof802,and150tons/yrofprimaryparticulate.EmissionsunitAemits200tons/yrofNOx,100tons/yrof802,and100tons/yrofprimaryparticulate.Otheremissionunits,unitsBthroughH,whichbeganoperatingin1966,contributelesseramountsofeachpollutant.Forthisexample,aBARTreviewisrequiredforNOx,802,andprimaryparticulate,andcontroloptionsmustbeanalyzedforunitsBthroughHaswellasunitA.C.HowdoesoBARTreviewrelotetoMoximumAchievobieControlTechnology(MACT)StondordsunderCAAsection112,ortootheremissionlimitotionsrequiredundertheCAA?ForVOCandPMsoucessubjecttoMACFstandards,StatesmaystreamlinetheanalysisbyincludingadiscussionoftheMACFcontrolsandwhetheranymajornewtechnologieshavebeendevelopedsubsequenttotheMACTstandards.WebelievethattherearemanyVOCandPMsourcesthatarewellcontrolledbecausetheyareregulatedbytheMACTstandards,whichEPAdevelopedunderCAAsection112,ForafewMACTstandards,thismayalsobetruefor802.AnysourcesubjecttoMACFstandardsmustmeetalevelthatisasstringentasthebest-controlled12percentofsourcesintheindustry.ExamplesofthesehazardousairpollutantsourceswhicheffectivelycontrolVOCandPMemissionsinclude(amongothers)secondaryleadfacilities,organicchemicalplantssubjecttothehazardousorganicNESHAP(HON),pharmaceuticalproductionfacilities,andequipmentleaksandwastewateroperationsatpetroleumrefineries.Webelievethat,inmanycases,itwillbeunlikelythatStateswillidentifyemissioncontrolsmorestringentthantheMACTstandardswithout11Thatis,emissionunitsthatwereinexistenceonAugust7,1977andwhichbeganactualoperationonorafterAugust7,1962.39164FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsidentifyingcontroloptionsthatwouldcostmanythousandsofdollarsperton.UnlesstherearenewtechnologiessubsequenttotheMACTstandardswhichwouldleadtocosteffectiveincreasesinthelevelofcontrol,youmayrelyontheMACI’standardsforpurposesofBART.WebelievethatthesamerationalealsoholdstrueforemissionsstandardsdevelopedformunicipalwasteincineratorsunderCAAsection111(d),andformanyNSR/PSDdeterminationsandNSR/PSDsettlementagreements.However,wedonotbelievethattechnologydeterminationsfromthe1970sorearly1980s,includingnewsourceperformancestandards(NSPS),shouldbeconsideredtorepresentbestcontrolforexistingsources,asbestcontrollevelsforrecentplantretrofitsaremorestringentthantheseolderlevels.WhereyouarerelyingonthesestandardstorepresentaBARTlevelofcontrol,youshouldprovidethepublicwithadiscussionofwhetheranynewtechnologieshavesubsequentlybecomeavailable.D.WhotAretheFiveBosicStepsofoCoseby-CoseBARTAnolysis?Thefivestepsare:STEP1—IdentifyAll12AvailableRetrofitControlTechnologies,STEP2—EliminateTechnicallyInfeasibleOptions,STEP3—EvaluateControlEffectivenessofRemainingControlTechnologies,STEP4—EvaluateImpactsandDocumenttheResults,andSTEP5—EvaluateVisibilityImpacts.1.STEP1:HowdoIidentifyallavailableretrofitemissioncontroltechniques?1.Availableretrofitcontroloptionsarethoseairpollutioncontroltechnologieswithapracticalpotentialforapplicationtotheemissionsunitandtheregulatedpollutantunderevaluation.Airpollutioncontroltechnologiescanincludeawidevarietyofavailablemethods,systems,andtechniquesforcontroloftheaffectedpollutant.TechnologiesrequiredasBACTorLAERareavailableforDARTpurposesandmustbeincludedascontrolalternatives.Thecontrolalternativescanincludenotonlyexistingcontrolsforthesourcecategoryinquestionbutalsotakeintoaccounttechnologytransferofcontrolsthathavebeenappliedtosimilarsourcecategoriesandgasstreams.Technologieswhichhavenotyetbeenappliedto(orpermittedfor)fullscaleoperationsneednotbeconsideredasavailable;wedonotexpectthesourceownertopurchaseorconstructaprocessorcontroldevicethathasnotalreadybeendemonstratedinpractice.2.WhereaNSPSexistsforasourcecategory(whichisthecaseformostofthecategoriesaffectedbyBART),youshouldincludealevelofcontrolequivalenttothe‘21nidentifyingall”options,youmustidentifythemoststringentoptionandareasonablesetofoptionsforanalysisthatreflectsacomprehensivelistofavailabletectmologies.Itisnotnecessarytolistallpermutationsofavailablecontrollevelsthatexistforagiventechnology—thelistiscompleteifitincludesthemaximumlevelofcontroleachtechnologyiscapableofachieving,NSPSasoneofthecontroloptions.13TheNSPSstandardsarecodifiedin40CFRpart60.WenotethattherearesituationswhereNSPSstandardsdonotrequirethemoststringentlevelofavailablecontrolforallsourceswithinacategory.Forexample,postcombustionNOxcontrols(themoststringentcontrolsforstationarygasturbines)arenotrequiredundersubpartCCoftheNSPSforStationaryGasTurbines.However,suchcontrolsmuststillbeconsideredavailabletechnologiesfortheBARTselectionprocess.3.Potentiallyapplicableretrofitcontrolalternativescanbecategorizedinthreeways.•Pollutionprevention:useofinherentlylower-emittingprocesses/practices,includingtheuseofcontroltechniques(e.g.low-NOxburners)andworkpracticesthatpreventemissionsandresultinlower“productionspecific”emissions(notethatitisnotourintenttodirectStatestoswitchfuelforms,e.g.fromcoaltogas),•Useof(andwherealreadyinplace,improvementintheperformanceof)add-oncontrols,suchasscrubbers,fabricfilters,thermaloxidizersandotherdevicesthatcontrolandreduceemissionsaftertheyareproduced,and•Combinationsofinherentlyloweremittingprocessesandadd-oncontrols.4.InthecourseoftheBARTreview,oneormoreoftheavailablecontroloptionsmaybeeliminatedfromconsiderationbecausetheyaredemonstratedtobetechnicallyinfeasibleortohaveunacceptableenergy,cost,ornon-airqualityenvironmentalimpactsonacase-by-case(orsite-specific)basis,However,attheoutset,youshouldinitiallyidentifyallcontroloptionswithpotentialapplicationtotheemissionsunitunderreview.5.WedonotconsiderDARTasarequirementtoredesignthesourcewhenconsideringavailablecontrolalternatives.Forexample,wherethesourcesubjecttoDARTisacoal-firedelectricgenerator,wedonotrequiretheBARTanalysistoconsiderbuildinganaturalgas-firedelectricturbinealthoughtheturbinemaybeinherentlylesspollutingonaperunitbasis.6.ForemissionunitssubjecttoaDARTreview,therewilloftenbecontrolmeasuresordevicesalreadyinplace.Forsuchemissionunits,itisimportanttoincludecontroloptionsthatinvolveimprovementstoexistingcontrolsandnottolimitthecontroloptionsonlytothosemeasuresthatinvolveacompletereplacementofcontroldevices.Exomple:Forapowerplantwithanexistingwetscrubber,thecurrentcontrolefficiencyis66percent.Partofthereasonfor13thEPA’s1980BARTguidelinesforreasonablyattributablevisibilityimpairment,weconcludedthatN5P5standardsgenerally,atthattime,representedthebestlevelsourceecouldinstallasDART.Inthe20yearperiodsincethisguidancewasdeveloped,therehavebeenadvancesin502controltechnologiesaswellastechnologiesforthecontrolofotherpollutants,confirmedbyanumberofrecentretrofitsatWesternpowerplants.Accordingly,EPAnolongerconcludesthattheNSPSlevelofcontrolsautomaticallyrepresents“thebestthesesourcescaninstall.”AnalysisoftheDARTfactorscouldresultintheselectionofaNSPSlevelofcontrol,butyoushouldreachthisconclusiononlyafterconsideringthefullrangeofcontroloptions.therelativelylowcontrolefficiencyisthat22percentofthegasstreambypassesthescrubber.ABARTreviewidentifiesoptionsforimprovingtheperformanceofthewetscrubberbyredesigningtheinternalcomponentsofthescrubberandbyeliminatingorreducingthepercentageofthegasstreamthatbypassesthescrubber.Fourcontroloptionsareidentified:(1)78percentcontrolbaseduponimprovedscrubberperformancewhilemaintainingthe22percentbypass,(2)83percentcontrolbaseduponimprovedscrubberperformancewhilereducingthebypassto15percent,(3)93percentcontrolbaseduponimprovingthescrubberperformancewhileeliminatingthebypassentirely,(thisoptionresultsina“wetstack”operationinwhichthegasleavingthestackissaturatedwithwater)and(4)93percentasinoption3,withtheadditionofanindirectreheatsystemtoreheatthestackgasabovethesaturationtemperature.YoumustconsidereachofthesefouroptionsinaDARTanalysisforthissource.7.Youareexpectedtoidentifypotentiallyapplicableretrofitcontroltechnologiesthatrepresentthefullrangeofdemonstratedalternatives.Examplesofgeneralinformationsourcestoconsiderinclude:•TheEPA’sCleanAirTechnologyCenter,whichincludestheRACT/BACT/LAERClearinghouse(RBLC);•StateandLocalBestAvailableControlTechnologyGuidelines—manyagencieshaveonlineinformation—forexampleSouthCoastAirQualityManagementDistrict,BayAreaAirQualityManagementDistrict,andTexasNaturalResourcesConservationCommission;•Controltechnologyvendors;•Federal/State/LocalNSRpermitsandassociatedinspection/performancetestreports;•Environmentalconsultants;•Technicaljournals,reportsandnewsletters,airpollutioncontrolseminars;and•TheEPA’sNSRbulletinboard—htfp://www.epo.gov/ttn/nsr;•DepartmentofEnergy’sCleanCoalProgram—technicalreports;•TheNOxControlTechnology“CostTool”—CleanAirMarketsDivisionWebpage—http://www.epo.gov/oirmorkets/orp/nox/controltechhtml;•Performanceofselectivecatalyticreductiononcoal-firedsteamgeneratingunits—finalreport.OAR/ARD,June1997(alsoavailableathttp://www.epo.gov/oirmorkets/orp/nox/controltechhtml);•CostestimatesforselectedapplicationsofNOxcontroltechnologiesonstationarycombustionboilers.OAR/ARDJune1997.(DocketforNOxSIPCall,A—96—56,itemII—A—03);•InvestigationofperformanceandcostofNOxcontrolsasappliedtogroup2boilers.OAR/ARD,August1996.(DocketforPhaseIINOxrule,A—95—28,itemIV—A—4);•ControllingSO2Emissions:AReviewofTechnologies.EPA—600/R--00—093,USEPA/ORD/NRMRL,October2000;and•TheOAQPSControlCostManual.Youareexpectedtocompileappropriateinformationfromtheseinformationsources.8.TheremaybesituationswhereaspecificsetofunitswithinafencelineconstitutestheFederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulations39165logicalsettowhichcontrolswouldapplyandthatsetofunitsmayormaynotallbeDART-eligible.(Forexample,someunitsinthatsetmaynothavebeenconstructedbetween1962and1977.)9.IfyoufindthataBARTsourcehascontrolsalreadyinplacewhicharethemoststringentcontrolsavailable(notethatthismeansthatallpossibleimprovementstoanycontroldeviceshavebeenmade),thenitisnotnecessarytocomprehensivelycompleteeachfollowingstepoftheBARTanalysisinthissection.AslongthesemoststringentcontrolsavailablearemadefederallyenforceableforthepurposeofimplementingBARTforthatsource,youmayskiptheremaininganalysesinthissection,includingthevisibilityanalysisinstep5.Likewise,ifasourcecommitstoaBARTdeterminationthatconsistsofthemoststringentcontrolsavailable,thenthereisnoneedtocompletetheremaininganalysesinthissection.2.STEP2;HowdoIdeterminewhethertheoptionsidentifiedinStepIaretechnicallyfeasible?InStep2,youevaluatethetechnicalfeasibilityofthecontroloptionsyouidentifiedinStep1.Youshoulddocumentademonstrationoftechnicalinfeasibilityandshouldexplain,basedonphysical,chemical,orengineeringprinciples,whytechnicaldifficultieswouldprecludethesuccessfuluseofthecontroloptionontheemissionsunitunderreview.YoumaytheneliminatesuchtechnicallyinfeasiblecontroloptionsfromfurtherconsiderationintheBARTanalysis.Ingeneral,whatdowemeanbytechnicalfeasibility?Controltechnologiesaretechnicallyfeasibleifeither(1)theyhavebeeninstalledandoperatedsuccessfullyforthetypeofsourceunderreviewundersimilarconditions,or(2)thetechnologycouldbeappliedtothesourceunderreview.Twokeyconceptsareimportantindeterminingwhetheratechnologycouldbeapplied;“availability”and“applicability.”Asexplainedinmoredetailbelow,atechnologyisconsidered“available”ifthesourceownermayobtainitthroughcommercialchannels,oritisotherwiseavailablewithinthecommonsensemeaningoftheterm.Anavailabletechnologyis“applicable”ifitcanreasonablybeinstalledandoperatedonthesourcetypeunderconsideration.Atechnologythatisavailableandapplicableistechnicallyfeasible.Whatdowemeanby“available”technology?1.Thetypicalstagesforbringingacontroltechnologyconcepttorealityasacommercialproductare;•Conceptstage;•Researchandpatenting;•Benchscaleorlaboratorytesting;•Pilotscaletesting;•Licensingandcommercialdemonstration;and•Commercialsales.2.Acontroltechniqueisconsideredavailable,withinthecontextpresentedabove,ifithasreachedthestageoflicensingandcommercialavailability.Similarly,wedonotexpectasourceownertoconductextendedtrialstolearnhowtoapplyatechnologyonatotallynewanddissimilarsourcetype.Consequently,youwouldnotconsidertechnologiesinthepilotscaletestingstagesofdevelopmentas“available”forpurposesofDARTreview.3.Commercialavailabilitybyitself,however,isnotnecessarilyasufficientbasisforconcludingatechnologytobeapplicableandthereforetechnicallyfeasible.Technicalfeasibility,asdeterminedinStep2,alsomeansacontroloptionmayreasonablybedeployedonor“applicable”tothesourcetypeunderconsideration.BecauseanewtechnologymaybecomeavailableatvariouspointsintimeduringtheBARTanalysisprocess,webelievethatguidelinesareneededonwhenatechnologymustbeconsidered.Forexample,atechnologymaybecomeavailableduringthepubliccommentperiodontheState’sruledevelopmentprocess.Likewise,itispossiblethatnewtechnologiesmaybecomeavailableafterthecloseoftheState’spubliccommentperiodandbeforesubmittaloftheSIPtoEPA,orduringEPA’sreviewprocessontheSIPsubmittal.Inordertoprovidecertaintyintheprocess,alltechnologiesshouldbeconsideredifavailablebeforethecloseoftheState’spubliccommentperiod.Youneednotconsidertechnologiesthatbecomeavailableafterthisdata.Aspartofyouranalysis,youshouldconsideranytechnologiesbroughttoyourattentioninpubliccomments.Ifyoudisagreewithpubliccommentsassertingthatthetechnologyisavailable,youshouldprovideanexplanationforthepublicrecordastothebasisforyourconclusion.Whatdowemeanby“applicable”technology?Youneedtoexercisetechnicaljudgmentindeterminingwhetheracontrolalternativeisapplicabletothesourcetypeunderconsideration.Ingeneral,acommerciallyavailablecontroloptionwillbepresumedapplicableifithasbeenusedonthesameorasimilarsourcetype.Absentashowingofthistype,youevaluatetechnicalfeasibilitybyexaminingthephysicalandchemicalcharacteristicsofthepollutant-bearinggasstream,andcomparingthemtothegasstreamcharacteristicsofthesourcetypestowhichthetechnologyhadbeenappliedpreviously.Deploymentofthecontroltechnologyonaneworexistingsourcewithsimilargasstreamcharacteristicsisgenerallyasufficientbasisforconcludingthetechnologyistechnicallyfeasiblebarringademonstrationtothecontraryasdescribedbelow.WhattypeofdemonstrationisrequiredifIconcludethatanoptionisnottechnicallyfeasible?1.WhereyouconcludethatacontroloptionidentifiedinStepIistechnicallyinfeasible,youshoulddemonstratethattheoptioniseithercommerciallyunavailable,orthatspecificcircumstancesprecludeitsapplicationtoaparticularemissionunit.Generally,suchademonstrationinvolvesanevaluationofthecharacteristicsofthepollutant-bearinggasstreamandthecapabilitiesofthetechnology.Alternatively,ademonstrationoftechnicalinfeasibilitymayinvolveashowingthatthereareunresolvabletechnicaldifficultieswithapplyingthecontroltothesource(e.g.,sizeoftheunit,locationoftheproposedsite,operatingproblemsrelatedtospecificcircumstancesofthesource,spaceconstraints,reliability,andadversesideeffectsontherestofthefacility).Wheretheresolutionoftechnicaldifficultiesismerelyamatterofincreasedcost,youshouldconsiderthetechnologytobetechnicallyfeasible.Thecostofacontrolalternativeisconsideredlaterintheprocess.2.Thedeterminationoftechnicalfeasibilityissometimesinfluencedbyrecentairqualitypermits.Insomecases,anairqualitypermitmayrequireacertainlevelofcontrol,butthelevelofcontrolinapermitisnotexpectedtobeachievedinpractice(e.g.,asourcehasreceivedapermitbuttheprojectwascanceled,oreveryoperatingsourceatthatpermittedlevelhasbeenphysicallyunabletoachievecompliancewiththelimit).Wherethisisthecase,youshouldprovidesupportingdocumentationshowingwhysuchlimitsarenottechnicallyfeasible,and,therefore,whythelevelofcontrol(butnotnecessarilythetechnology)maybeeliminatedfromfurtherconsideration.However,ifthereisapermitrequiringtheapplicationofacertaintechnologyoremissionlimittobeachievedforsuchtechnology,thisusuallyissufficientjustificationforyoutoassumethetechnicalfeasibilityofthattechnologyoremissionlimit.3.Physicalmodificationsneededtoresolvetechnicalobstaclesdonot,inandofthemselves,provideajustificationforeliminatingthecontroltechniqueonthebasisoftechnicalinfeasibility.However,youmayconsiderthecostofsuchmodificationsinestimatingcosts.This,inturn,mayformthebasisforeliminatingacontroltechnology(seelaterdiscussion).4.Vendorguaranteesmayprovideanindicationofcommercialavailabilityandthetechnicalfeasibilityofacontroltechniqueandcouldcontributetoadeterminationoftechnicalfeasibilityortechnicalinfeasibility,dependingoncircumstances.However,wedonotconsideravendorguaranteealonetobesufficientjustificationthatacontroloptionwillwork.Conversely,lackofavendorguaranteebyitselfdoesnotpresentsufficientjustificationthatacontroloptionoranemissionslimitistechnicallyinfeasible.Generally,youshouldmakedecisionsabouttechnicalfeasibilitybasedonchemical,andengineeringanalyses(asdiscussedabove),inconjunctionwithinformationaboutvendorguarantees.5.ApossibleoutcomeoftheBARTproceduresdiscussedintheseguidelinesistheevaluationofmultiplecontroltechnologyalternativeswhichresultinessentiallyequivalentemissions.Itisnotourintenttoencourageevaluationofunnecessarilylargenumbersofcontrolalternativesforeveryemissionsunit.Consequently,youshouldusejudgmentindecidingonthosealternativesforwhichyouwillconductthedetailedimpactsanalysis(Step4below).Forexample,iftwoormorecontroltechniquesresultincontrollevelsthatareessentiallyidentical,consideringtheuncertaintiesofemissionsfactorsandotherparameters39166FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationspertinenttoestimatingperformance,youmayevaluateonlythelesscostlyoftheseoptions.YoushouldnarrowthescopeoftheBARTanalysisinthiswayonlyifthereisanegligibledifferenceinemissionsandenergyandnon-airqualityenvironmentalimpactsbetweencontrolalternatives.3.STEP3:HowdoIevaluatetechnicallyfeasiblealternatives?Step3involvesevaluatingthecontroleffectivenessofallthetechnicallyfeasiblecontrolalternativesidentifiedinStep2forthepollutantandemissionsunitunderreview.Twokeyissuesinthisprocessinclude:(1)Makingsurethatyouexpressthedegreeofcontrolusingametricthatensuresan“applestoapples”comparisonofemissionsperformancelevelsamongoptions,and(2)Givingappropriatetreatmentandconsiderationofcontroltechniquesthatcanoperateoverawiderangeofemissionperformancelevels.Whataretheappropriatemetricsforcomparison?Thisissueisespeciallyimportantwhenyoucompareinherentlylower-pollutingprocessestooneanotherortoadd-oncontrols.Insuchcases,itisgenerallymosteffectivetoexpressemissionsperformanceasanaveragesteadystateemissionslevelperunitofproductproducedorprocessed.Examplesofcommonmetrics:•PoundsofSO2emissionspermillionBtuheatinput,and•PoundsofNOxemissionspertonofcementproduced.HowdoIevaluatecontroltechniqueswithawiderangeofemissionperformancelevels?1.Manycontroltechniques,includingbothadd-oncontrolsandinherentlylowerpollutingprocesses,canperformatawiderangeoflevels.Scrubbersandhighandlowefficiencyelectrostaticprecipitators(ESP5)aretwoofthemanyexamplesofsuchcontroltechniquesthatcanperformatawiderangeoflevels.Itisnotourintenttorequireanalysisofeachpossiblelevelofefficiencyforacontroltechniqueassuchananalysiswouldresultinalargenumberofoptions.Itisimportant,however,thatinanalyzingthetechnologyyoutakeintoaccountthemoststringentemissioncontrollevelthatthetechnologyiscapableofachieving.Youshouldconsiderrecentregulatorydecisionsandperformancedata(e.g.,manufacturer’sdata,engineeringestimatesandtheexperienceofothersources)whenidentifyinganemissionsperformancelevelorlevelstoevaluate.2.Inassessingthecapabilityofthecontrolalternative,latitudeexiststoconsiderspecialcircumstancespertinenttothespecificsourceunderreview,orregardingthepriorapplicationofthecontrolalternative,However,youshouldexplainthebasisforchoosingthealternatelevel(orrange)ofcontrolintheDARTanalysis.Withoutashowingofdifferencesbetweenthesourceandothersourcesthathaveachievedmorestringentemissionslimits,youshouldconcludethatthelevelbeingachievedbythoseothersourcesisrepresentativeoftheachievablelevelforthesourcebeinganalyzed.3.Youmayencountercaseswhereyoumaywishtoevaluateotherlevelsofcontrolinadditiontothemoststringentlevelforagivendevice.Whileyoumustconsiderthemoststringentlevelasoneofthecontroloptions,youmayconsiderlessstringentlevelsofcontrolasadditionaloptions.Thiswouldbeuseful,particularlyincaseswheretheselectionofadditionaloptionswouldhavewidelyvaryingcostsandotherimpacts.4.Finally,wenotethatforretrofittingexistingsourcesinaddressingDART,youshouldconsiderwaystoimprovetheperformanceofexistingcontroldevices,particularlywhenacontroldeviceisnotachievingthelevelofcontrolthatothersimilarsourcesareachievinginpracticewiththesamedevice.Forexample,youshouldconsiderrequiringthosesourceswithelectrostaticprecipitators(ESPs)performingbelowcurrentlyachievablelevelstoimprovetheirperformance.4.STEP4:ForaDARTreview,whatimpactsamIexpectedtocalculateandreport?WhatmethodsdoesEPArecommendfortheimpactsanalysis?Afteryouidentifytheavailableandtechnicallyfeasiblecontroltechnologyoptions,youareexpectedtoconductthefollowinganalyseswhenyoumakeaBARTdetermination:Impactanalysispart1:Costsofcompliance,Impactanalysispart2:Energyimpacts,andImpactanalysispart3:Non-airqualityenvironmentalimpacts.Impactanalysispart4:Remainingusefullife.Inthissection,wedescribebowtoconducteachofthesethreeanalyses.Youareresponsibleforpresentinganevaluationofeachimpactalongwithappropriatesupportinginformation.Youshoulddiscussand,wherepossible,quantifybothbeneficialandadverseimpacts.Ingeneral,theanalysisshouldfocusonthedirectimpactofthecontrolalternative.a.Impactanalysispart1:howdoIestimatethecostsofcontrol?1.Toconductacostanalysis,you:(1)Identifytheemissionsunitsbeingcontrolled,(2)Identifydesignparametersforemissioncontrols,and(3)Developcostestimatesbaseduponthosedesignparameters.2.Itisimportanttoidentifyclearlytheemissionunitsbeingcontrolled,thatis,tospecifyawell-definedareaorprocesssegmentwithintheplant.Insomecases,multipleemissionunitscanbecontrolledjointly.However,inothercases,itmaybeappropriateinthecostanalysistoconsiderwhethermultipleunitswillberequiredtoinstallseparateand/ordifferentcontroldevices.Theanalysisshouldprovideaclearsummarylistofequipmentandtheassociatedcontrolcosts.Inadequatedocumentationoftheequipmentwhoseemissionsarebeingcontrolledisapotentialcauseforconfusionincomparisonofcostsofthesamecontrolsappliedtosimilarsources.3.Youthenspecifythecontrolsystemdesignparameters.Potentialsourcesofthesedesignparametersincludeequipmentvendors,backgroundinformationdocumentsusedtosupportNSPSdevelopment,controltechniqueguidelinesdocuments,costmanualsdevelopedbyEPA,controldataintradepublications,andengineeringandperformancetestdata.Thefollowingareafewexamplesofdesignparametersfortwoexamplecontrolmeasures:ControldeviceExamplesofdesignparametersWetScrubbers..Typeofsorbentused(lime,limestone,etc.).Gaspressuredrop.Liquid/gasratio.SelectiveCata-AmmoniatoNOxmolarlyticReduction,ratio.Pressuredrop.Catalystlife.4.Thevalueselectedforthedesignparametershouldensurethatthecontroloptionwillachievethelevelofemissioncontrolbeingevaluated.Youshouldincludeinyouranalysisdocumentationofyourassumptionsregardingdesignparameters.ExamplesofsupportingreferenceswouldincludetheEPAOAQPSControlCostMonuol(seebelow)andbackgroundinformationdocumentsusedforNSPSandhazardouspollutantemissionstandards.Ifthedesignparametersyouspecifieddifferfromtypicaldesigns,youshoulddocumentthedifferencebysupplyingperformancetestdataforthecontroltechnologyinquestionappliedtothesamesourceorasimilarsource.5.Oncethecontroltechnologyalternativesandachievableemissionsperformancelevelshavebeenidentified,youthendevelopestimatesofcapitalandannualcosts.Thebasisforequipmentcostestimatesalsoshouldbedocumented,eitherwithdatasuppliedbyanequipmentvendor(i.e.,budgetestimatesorbids)orbyareferencedsource(suchastheOAQPSControlCostMonuol,FifthEdition,February1996,EPA453/B96flO1).14Inordertomaintainandimproveconsistency,costestimatesshouldbebasedontheOA4QPSControlCostMonuol,wherepossible.15TheControlCostMonuoladdressesmostcontroltechnologiesinsufficientdetailforaBARTanalysis.Thecostanalysisshouldalsotakeintoaccountanysite-specificdesignorotherconditionsidentifiedabovethataffectthecostofaparticularDARTtechnologyoption.1TheOAQPSControlCostMonuolisupdatedperiodically.Whilethiscitationreferstothelatestversionatthetimethisguidancewaswritten,youshouldusetheversionthatiscurrentasofwhenyouconductyourimpactanalysis.Thisdocumentisavailableatthetollowingwebsite:http://wsvw.epo.gov/ttn/cotc/dirl/cslch2.pdf.55Youshouldincludedocumentationformyadditionalinformationyouusedforthecostcalculations,includinganyinformationsuppliedbyvendorsthataffectsyourassumptionsregardingpurchasedequipmentcosts,equipmentlife,replacementofmajorcomponents,andanyotherelementofthecalculationthatdiffersfromtheControlCostMonuol.

# Federal Register/Vol.

70,

No. 128/Wednesday,

July

6, 2005/Rules

and Regulations

39167 b. What

do

we mean

by cost effectiveness? Cost effectiveness,

in general,

is

a criterion used

to assess

the potential

for achieving

an objective

in the most economical

way.

For purposes

of

air pollutant

analysis, “effectiveness”

is measured

in terms

of tons of pollutant

emissions

removed,

and “cost” is measured

in terms

of annualized

control costs.

We recommend

two types

ofcosteffectiveness calculations—average

cost effectiveness,

and incremental

cost effectiveness. c. How

do

I calculate

average

cost effectiveness? Average

cost effectiveness

means

the total annualized

costs

of control

divided

by annual emissions reductions

(the difference between

baseline

annual emissions

and

the estimate

of emissions

after controls),

using the following

formula: Average

cost effectiveness

(dollars

per

tonremoved)=Controloptionannualizedcastle 

# Baseline

annual emissions—Annual emissions

with Control

option Because

you calculate

costs

in (annualized) dollars

per year

($/yr)

and because

you calculate

emissions

rates

in tons

per year (tons/yr),

the result

is

an average

costeffectiveness

number

in (annualized)

dollars per

ton (s/ton)

of pollutant

removed. d. How

do

I calculate

baseline emissions?1. 

# The baseline emissions

rate should represent

a realistic depiction

of anticipated annual emissions

for

the source.

In general, for

the existing

sources

subject

to BART,

you will estimate

the anticipated

annual emissions

based

upon

actual emissions

from a baseline

period.2. 

# When

you project

that future operating parameters

(e.g., limited

hours

of operationyoucalcutateorreportannualcosts,youshouldindicatetheyearforwhichthecostsareestimated.Forexample,ifyouusetheyear2000asthebasisforcostcomparisons,youwouldreportthatanannualizedcostof$20millionwouldbe:S20million(year2000dollars).orcapacityutilization,typeoffuel,raw 

# materials

or product

mix

or type)

will differ from

past practice,

and

if this projection

has a deciding

effect

in the DART determination, then

you must

make

these parameters

orassumptionsintoenforceablelimitations.In 

# the absence

of enforceable

limitations,

youcalculatebaselineemissionsbasedupon 

# continuation

of past practice.3.Forexample,thebaselineemissions 

# calculation

for

an emergency

standby generator

may consider

the

fact

that

the source

owner

would

not operate

more

than past practice

of2 

# weeks

a year.

On

the other hand, baseline emissions

associated

with

a base-loaded

turbine

should

be based

on

its past practice

which

would indicate

a large number

of hours

of operation.

This produces a significantly

higher

level

of baseline emissions

than

in the case

of the emergency/standbyunitand 

# results

in more

costeffective

controls.

As

a consequence

of the dissimilar

baseline emissions,

DART

for

the two cases

could

be very different. e. How

do

I calculate incremental

costeffectiveness?



# 1.

In addition

to the average

cost effectiveness

of

a control

option,

you shouldalsocalculateincrementalcosteffectiveness. 

# You should consider

the incremental

cost effectiveness

in combination

with

the average cost effectiveness

when considering

whether to eliminate

a control

option.

The incremental

cost effectiveness

calculation compares

the costs

and performance

level

of a control

option

to those

of the next

most stringent

option,

as shown

in the following formula

(with respect

to cost

per emissions reduction): Incremental

Cost Effectiveness

(dollars

per incremental

ton removed)= 

# (Total annualized

costs

of control

option)— 

# (Total annualized

costs

of next control option)÷ 

# (Control

option

annual emissions)— 

# (Next control

option annual emissions)ExampleI: 

# Assume

that Option

F on Figure2 

# has total annualized

costs

of$1 

# million

to reduce

2000

tons

of

a pollutant,

and

that Option

U

on Figure2 

# has totalannualizedcostsof$500,000toreduce1000 

# tons

of the same pollutant.

The incremental cost effectiveness

of Option

F relative

to Option

U

is($1 

# million—$500,000)



# dividedby(2000tons—1000tons),or$500,000 

# divided

by1000



# tons, which

is $500/ton.Exampie2: 

# Assume

that

two control options

exist: Option1andOption2.OptionIachievesa1,000ton/yrreductionatan 

# annualized

cost

of$1,900,000.



# Thisrepresentsanaveragecostof($1,900,000/1,000tons)= 

# $1,900/ton.

Option2achieves 

# a980 

# tons/yr reduction

at

an annualized

cost of$1,500,000.



# This represents

an average

costof(51,500,000/980tons)= 

# $1,531/ton.

The incremental

cost effectiveness

of Option1relativetoOption2is($1,900,000—$1,500,000)



# divided

by(1,000tons—980 

# tons).

The adoption

of Option1insteadof 

# Option2 

# results

in

an incremental

emissionreductionof20tonsperyear



# at

an additional cost

of$400,000



# per year.

The incrementalcostofOption1,then,is$20,000perton—11 

# times

the average

cost

of$1,900



# per

ton. While$1,900



# per

ton may

still

be deemedreasonable,



# it

is useful

to consider

both

the average

and incremental

cost

in making

an overall cost-effectiveness

finding.

Of course, there

may

be other differences

between

these options,

such

as, energy

or water

use,

ornonair environmental

effects,

which

also should be considered

in selecting

a DART technology.2. 

# You should exercise

care

in deriving incremental

costs

of candidate

control options. Incremental cost-effectiveness comparisons

should

focus

on annualized

cost andemissionreductiondifferencesbetween 

# “dominant”

alternatives.

To identify dominant alternatives,

you generate

a graphical

plot

of total annualized

costs

for total emissions

reductions

for

all control alternatives

identified

in the DART analysis, and

by identifying

a “least-cost

envelope”

as shown

in Figure

2.

(A “least-cost

envelope” represents

the

set

of options

that should

be dominant

in the choice

of

a specific

option.)39168FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsi 

# IExampie:Eighttechnicallyfeasiblecontroloptionsforanalysisarelisted.ThesearerepresentedasAthroughHinFigure2.Thedominantsetofcontroloptions,B,D,F,C,andH,representtheleast-costenvelope,aswedepictbythecostcurveconnectingthem.PointsA,CandEareinferioroptions,andyoushouldnotusethemincalculatingincrementalcosteffectiveness.PointsA,CandErepresentinferiorcontrolsbecauseBwillbuymoreemissionsreductionsforlessmoneythanA;andsimilarly,DandFwillbuymorereductionsforlessmoneythanCandE,respectively.3.Incalculatingincrementalcosts,you:(1)Arraythecontroloptionsinascendingorderofannualizedtotalcosts,(2)Developagraphofthemostreasonablesmoothcurveofthecontroloptions,asshowninFigure2.Thisistoshowthe“leastcostenvelope”discussedabove;and(3)Calculatetheincrementalcosteffectivenessforeachdominantoption,whichisthedifferenceintotalannualcostsbetweenthatoptionandthenextmoststringentoption,dividedbythedifferenceinemissions,aftercontrolshavebeenapplied,betweenthosetwocontroloptions.Forexample,usingFigure2,youwouldcalculateincrementalcosteffectivenessforthedifferencebetweenoptionsBandD,optionsDandF,optionsFandC,andoptionsCandH.4.Acomparisonofincrementalcostscanalsobeusefulinevaluatingtheviabilityofaspecificcontroloptionoverarangeofefficiencies.Forexample,dependingonthecapitalandoperationalcostofacontroldevice,totalandincrementalcostmayvarysignificantly(eitherincreasingordecreasing)overtheoperationalrangeofacontroldevice.Also,thegreaterthenumberofpossiblecontroloptionsthatexist,themoreweightshouldbegiventotheincrementalcostsvs.averagecosts.Itshouldbenotedthataverageandincrementalcosteffectivenessareidenticalwhenonlyonecandidatecontroloptionisknowntoexist.5.Youshouldexercisecautionnottomisusethesetechniques.Forexample,youmaybefacedwithachoicebetweentwoavailablecontroldevicesatasource,controlAandcontrolB,wherecontrolBachievesslightlygreateremissionreductions.Theaveragecost(totalannualcost/totalannualemissionreductions)foreachmaybedeemedtobereasonable.However,theincrementalcost(totalannualcostA—a/totalannualemissionreductionsA—a)oftheadditionalemissionreductionstobeachievedbycontrolBmaybeverygreat.Insuchaninstance,itmaybeinappropriatetochoosecontrolB,basedonitshighincrementalcosts,eventhoughitsaveragecostmaybeconsideredreasonable.6.Inaddition,whenyouevaluatetheaverageorincrementalcosteffectivenessofacontrolalternative,youshouldmakereasonableandsupportableassumptionsregardingcontrolefficiencies.Anunrealisticallylowassessmentoftheemissionreductionpotentialofacertaintechnologycouldresultininflatedcosteffectivenessfigures.f.WhatotherinformationshouldIprovideinthecostimpactsanalysis?Youshouldprovidedocumentationofanyunusualcircumstancesthatexistforthesourcethatwouldleadtocost-effectivenessestimatesthatwouldexceedthatforrecentretrofits.Thisisespeciallyimportantincaseswhererecentretrofitshavecost-effectivenessvaluesthatarewithinwhathasbeenconsideredareasonablerange,butyouranalysisconcludesthatcostsforthesourcebeinganalyzedarenotconsideredreasonable.(Areasonablerangewouldbearangethatisconsistentwiththerangeofcosteffectivenessvaluesusedinothersimilarpermitdecisionsoveraperiodoftime.)Example:Inanaridregion,largeamountsofwaterareneededforascrubbingsystem.Acquiringwaterfromadistantlocationcouldgreatlyincreasethecostpertonofemissionsreducedofwetscrubbingasacontroloption.g.Whatotherthingsareimportanttoconsiderinthecostimpactsanalysis?Inthecostanalysis,youshouldtakecarenottofocusonincompleteresultsorpartialcalculations,Forexample,largecapitalcostsforacontroloptionalonewouldnotprecludeselectionofacontrolmeasureiflargeemissionsreductionsareprojected.Insuchacase,loworreasonablecosteffectivenessnumbersmayvalidatetheoptionasanappropriateBARTalternativeirrespectiveofthelargecapitalcosts.Similarly,projectswithrelativelylowcapitalcostsmaynotbecosteffectiveiftherearefewemissionsreduced.h.Impactanalysispart2:HowshouldIanalyzeandreportenergyimpacts?1.Youshouldexaminetheenergyrequirementsofthecontroltechnologyanddeterminewhethertheuseofthattechnologyresultsinenergypenaltiesorbenefits.Asourceownermay,forexample,benefitfromthecombustionofaconcentratedgasstreamrichinvolatileorganiccompounds;ontheotherhand,moreoftenextrafuelorelectricityisrequiredtopoweracontrolHDominantcontrols(B,D,F,G,H)lieonenvelope0InferiorCostsAEmissions11ItIIIIIIWICREASINGEMISSiONSREDUCTION(rons/yr)wFederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulations39169deviceorincinerateadilutegasstream.Ifsuchbenefitsorpenaltiesexist,theyshouldhequantifiedtotheextentpracticable.Becauseenergypenaltiesorbenefitscanusuallybequaotifiedintermsofadditionalcostorincometothesource,theenergyimpactsanalysiscan,inmostcases,simplybefactoredintothecostimpactsanalysis.Thefactofenergyuseinandofitselfdoesnotdisqualifyatechnology.2.Yourenergyimpactanalysisshouldconsideronlydirectenergyconsumptionandnotindirectenergyimpacts.Forexample,youcouldestimatethedirectenergyimpactsofthecontrolalternativeinunitsofenergyconsumptionatthesource(e.g.,BTU,kwh,barrelsofoil,tonsofcoal).Theenergyrequirementsofthecontroloptionsshouldheshownintermsoftotal(andincertaincases,alsoincremental)energycostspertonofpollutantremoved.Youcanthenconverttheseunitsintodollarcostsand,whereappropriate,factorthesecostsintothecontrolcostanalysis.3.Yougenerallydonotconsiderindirectenergyimpacts(suchasenergytoproducerawmaterialsforconstructionofcontrolequipment).However,ifyoudetermine,eitherindependentlyorbasedonashowingbythesourceowner,thattheindirectenergyimpactisunusualorsignificantandthattheimpactcanbewellquantified,youmayconsidertheindirectimpact.4.Theenergyimpactanalysismayalsoaddressconcernsovertheuseoflocallyscarcefuels.Thedesignationofascarcefuelmayvaryfromregiontoregion.However,ingeneral,ascarcefuelisonewhichisinshortsupplylocallyandcanbebetterusedforalternativepurposes,oronewhichmaynotbereasonablyavailabletothesourceeitheratthepresenttimeorinthenearfuture.5.Finally,theenergyimpactsanalysismayconsiderwhethertherearerelativedifferencesbetweenalternativesregardingtheuseoflocallyorregionallyavailablecoal,andwhetheragivenalternativewouldresultinsignificanteconomicdisruptionorunemployment.Forexample,wheretwooptionsareequallycosteffectiveandachieveequivalentorsimilaremissionsreductions,oneoptionmaybepreferrediftheotheralternativeresultsinsignificantdisruptionorunemployment.I.Impactanalysispart3:HowdoIanalyze“non-airqualityenvironmentalimpacts?”1.Inthenon-airqualityrelatedenvironmentalimpactsportionoftheBARTanalysis,youaddressenvironmentalimpactsotherthanairqualityduetoemissionsofthepollutantinquestion.Suchenvironmentalimpactsincludesolidorhazardouswastegenerationanddischargesofpollutedwaterfromacontroldevice.2.Youshouldidentifyanysignificantorunusualenvironmentalimpactsassociatedwithacontrolalternativethathavetbepotentialtoaffecttheselectionoreliminationofacontrolalternative.Somecontroltechnologiesmayhavepotentiallysignificantsecondaryenvironmentalimpacts.Scrubbereffluent,forexample,mayaffectwaterqualityandlanduse.Alternatively,wateravailabilitymayaffectthefeasibilityandcostsofwetscrubbers.Otherexamplesofsecondaryenvironmentalimpactscouldincludehazardouswastedischarges,suchasspentcatalystsorcontaminatedcarbon.Generally,thesetypesofenvironmentalconcernsbecomeimportantwhensensitivesite-specificreceptorsexistorwhentheincrementalemissionsreductionspotentialofthemorestringentcontrolisonlymarginallygreaterthanthenextmosteffectiveoption.However,thefactthatacontroldevicecreatesliquidandsolidwastethatmustbedisposedofdoesnotnecessarilyargueagainstselectionofthattechnologyasBART,particularlyifthecontroldevicehasbeenappliedtosimilarfacilitieselsewhereandthesolidorliquidwasteissimilartothoseotherapplications.Ontheotherhand,whereyouorthesourceownercanshowthatunusualcircumstancesattheproposedfacilitycreategreaterproblemsthanexperiencedelsewhere,thismayprovideabasisfortheeliminationofthatcontrolalternativeasBART.3.Theprocedureforconductingananalysisofnon-airqualityenvironmentalimpactsshouldbemadebasedonaconsiderationofsite-specificcircumstances.Ifyouproposetoadoptthemoststringentalternative,thenitisnotnecessarytoperformthisanalysisofenvironmentalimpactsfortheentirelistoftechnologiesyourankedinStep3.Ingeneral,theanalysisneedonlyaddressthosecontrolalternativeswithanysignificantorunusualenvironmentalimpactsthathavethepotentialtoaffecttheselectionofacontrolalternative,oreliminationofamorestringentcontrolalternative.Thus,anyimportantrelativeenvironmentalimpacts(bothpositiveandnegative)ofalternativescanbecomparedwitheachother.4.Ingeneral,theanalysisofimpactsstartswiththeidentificationandquantificationofthesolid,liquid,andgaseousdischargesfromthecontroldeviceordevicesunderreview.Initially,youshouldperformaqualitativeorsemi-quantitativescreeningtonarrowtheanalysistodischargeswithpotentialforcausingadverseenvironmentaleffects.Next,youshouldassessthemassandcompositionofanysuchdischargesandquantifythemtotheextentpossible,basedonreadilyavailableinformation.Youshouldalsoassemblepertinentinformationaboutthepublicorenvironmentalconsequencesofreleasingthesematerials.j.Impactanalysispart4:whatareexamplesofnon-airqualityenvironmentalimpacts?Thefollowingareexamplesofhowtoconductnon-airqualityenvironmentalimpacts:(1)WoterlmpoctYoushouldidentifytherelativequantitiesofwaterusedandwaterpollutantsproducedanddischargedasaresultoftheuseofeachalternativeemissioncontrolsystem.wherepossible,youshouldassesstheeffectongroundwaterandsuchlocalsurfacewaterqualityparametersasph,turbidity,dissolvedoxygen,salinity,toxicchemicallevels,temperature,andanyotherimportantconsiderations.Theanalysiscouldconsiderwhetherapplicablewaterqualitystandardswillbemetandtheavailabilityandeffectivenessofvarioustechniquestoreducepotentialadverseeffects.(2)SolidWosteDisposolImpoctYoucouldalsocomparethequalityandquantityofsolidwaste(e.g.,sludges,solids)thatmustbestoredanddisposedoforrecycledasaresultoftheapplicationofeachalternativeemissioncontrolsystem.Youshouldconsiderthecompositionandvariousothercharacteristicsofthesolidwaste(suchaspermeability,waterretention,rewateringofdriedmaterial,compressionstrength,leachabilityofdissolvedions,bulkdensity,abilitytosupportvegetationgrowthandhazardouscharacteristics)whicharesignificantwithregardtopotentialsurfacewaterpollutionortransportintoandcontaminationofsubsurfacewatersoraquifers.(3)IrreversibleorIrretrievobleCommitmentofResourcesYoumayconsidertheextenttowhichthealternativeemissioncontrolsystemsmayinvolveatrade-offbetweenshort-termenvironmentalgainsattheexpenseoflongtermenvironmentallossesandtheextenttowhichthealternativesystemsmayresultinirreversibleorirretrievablecommitmentofresources(forexample,useofscarcewaterresources).(4)OtherAdverseEnvironmentolImpoctsYoumayconsidersignificantdifferencesinnoiselevels,radiantheat,ordissipatedstaticelectricalenergyofpollutioncontrolalternatives.Otherexamplesofnon-airqualityenvironmentalimpactswouldincludehazardouswastedischargessuchasspentcatalystsorcontaminatedcarbon.k.HowdoItakeintoaccountaproject’s“remainingusefullife”incalculatingcontrolcosts?1.Youmaydecidetotreattherequirementtoconsiderthesource’s“remainingusefullife”ofthesourceforBARTdeterminationsasoneelementoftheoverallcostanalysis.The“remainingusefullife”ofasource,ifitrepresentsarelativelyshorttimeperiod,mayaffecttheannualizedcostsofretrofitcontrols.Forexample,themethodsforcalculatingannualizedcostsinEPA’sOAQPSControlCostMonuolrequiretheuseofaspecifiedtimeperiodforamortizationthatvariesbaseduponthetypeofcontrol.Iftheremainingusefullifewillclearlyexceedthistimeperiod,theremainingusefullifehasessentiallynoeffectoncontrolcostsandontheBARTdeterminationprocess.wheretheremainingusefullifeislessthanthetimeperiodforamortizingcosts,youshouldusethisshortertimeperiodinyourcostcalculations.2.Forpurposesoftheseguidelines,theremainingusefullifeisthedifferencebetween:(1)Thedatethatcontrolswillbeputinplace(capitalandotherconstructioncostsincurredbeforecontrolsareputinplacecanberolledintothefirstyear,assuggestedinEPA’sOAQPSControlCostMonuol);youareconductingtheBARTanalysis;and(2)Thedatethefacilitypermanentlystopsoperations,wherethisaffectstheBARTdetermination,thisdateshouldbeassuredbyafederally-orState-enforceablerestrictionpreventingfurtheroperation.3.werecognizethattheremaybesituationswhereasourceoperatorintendstoshutdownasourcebyagivendate,butwishestoretaintheflexibilitytocontinue39170FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsoperatingbeyondthatdateintheevent,forexample,thatmarketconditionschange.Wherethisisthecase,yourBARTanalysismayaccountforthis,butitmustmaintainconsistencywiththestatutoryrequirementtoinstallBARTwithin5years.Wherethesourcechoosesnottoacceptafederallyenforceableconditionrequiringthesourcetoshutdownbyagivendate,itisnecessarytodeterminewhetherareducedtimeperiodfortheremainingusefullifechangesthelevelofcontrolsthatwouldhavebeenrequiredasBART.IfthereducedtimeperioddoeschangethelevelofBARTcontrols,youmayidentify,andincludeaspartoftheHARTemissionlimitation,themorestringentlevelofcontrolthatwouldberequiredasHARTiftherewerenoassumptionthatreducedtheremainingusefullife.YoumayincorporateintotheHARTemissionlimitthismorestringentlevel,whichwouldserveasacontingencyshouldthesourcecontinueoperatingmorethan5yearsafterthedateEPAapprovestherelevantSIP,Thesourcewouldnotbeallowedtooperateafterthe5-yearmarkwithoutsuchcontrols.Ifasourcedoesoperateafterthe5-yearmarkwithoutHARTinplace,thesourceisconsideredtobeinviolationoftheHARTemissionslimitforeachdayofoperation.5.Step5:HowshouldIdeterminevisibilityimpactsintheHARTdetermination?Thefollowingisanapproachyoumayusetodeterminevisibilityimpacts(thedegreeofvisibilityimprovementforeachsourcesubjecttoHART)fortheHARTdetermination.OnceyouhavedeterminedthatyoursourceorsourcesaresubjecttoBART,youmustconductavisibilityimprovementdeterminationforthesource(s)aspartoftheHARTdetermination.Whenmakingthisdetermination,webelieveyouhaveflexibilityinsettingabsolutethresholds,targetlevelsofimprovement,ordominimislevelssincethedeciviewimprovementmustbeweighedamongthefivefactors,andyouarefreetodeterminetheweightandsignificancetobeassignedtoeachfactor.Forexample,a0.3deciviewimprovementmaymeritastrongerweightinginonecaseversusanother,soone“brightline”maynotheappropriate.[Notethatifsourceshaveelectedtoapplythemoststringentcontrolsavailable,consistentwiththediscussioninsectionE.step1.below,youneednotconduct,orrequirethesourcetoconduct,anairqualitymodelinganalysisforthepurposeofdeterminingitsvisibilityimpacts.)UseCALPUFF,’7orotherappropriatedispersionmodeltodeterminethevisibilityimprovementexpectedataClassIareafromthepotentialHARTcontroltechnologyappliedtothesource.Modelingshouldbeconductedfor502,NOx,anddirectPMemissions(PM15and/orPM10).Ifthesourceismakingthevisibilitydetermination,youshouldreviewandapproveordisapproveofthesource’sanalysisbeforemakingtheexpectedimprovementdetermination.Thereareseveralstepsfordeterminingthe“Themodelcodeanditsdocumentationareavailableatnocostfordownloadfromhttp://www.epa.govlscromOolltt22.hfm#calpuff.visibilityimpactsfromanindividualsourceusingadispersionmodel:•Developamodelingprotocol.Somecriticalitemstoincludeinamodelingprotocolaremeteorologicalandterraindata,aswellassource-specificinformation(stackheight,temperature,exitvelocity,elevation,andallowableandactualemissionratesofapplicablepollutants),andreceptordatafromappropriateClassIareas.WerecommendfollowingEPA’sInteragencyWorkgrouponAirQualifyModeling(IWAQM)Phase2SummaryReportandRecommendationsforModelingLongRangeTransportImpacts’5forparametersettingsandmeteorologicaldatainputs;theuseofothersettingsfromthoseinIWAQMshouldbeidentifiedandexplainedintheprotocol.Oneimportantelementoftheprotocolisinestablishingthereceptorsthatwillbeusedinthemodel.ThereceptorsthatyouuseshouldbelocatedinthenearestClassIareawithsufficientdensitytoidentifythelikelyvisibilityeffectsofthesource.ForotherClassIareasinrelativelycloseproximitytoaHART-eligiblesource,youmaymodelafewstrategicreceptorstodeterminewhethereffectsatthoseareasmaybegreaterthanatthenearestClassIarea.Forexample,youmightchosetolocatereceptorsattheseareasattheclosestpointtothesource,atthehighestandlowestelevationintheClassIarea,attheIMPROVEmonitor,andattheapproximateexpectedplumereleaseheight.IfthehighestmodeledeffectsareobservedatthenearestClassIarea,youmaychoosenottoanalyzetheotherClassIareasanyfurtherasadditionalanalysesmightbeunwarranted.YoushouldbearinmindthatsomereceptorswithintherelevantClassIareamaybelessthan50kmfromthesourcewhileotherreceptorswithinthatsameClassIareamaybegreaterthan50kmfromthesamesource.AsindicatedbytheGuidelineonAirQualifyModels,thissituationmaycallfortheuseoftwodifferentmodelingapproachesforthesameClassIareaandsource,dependingupontheState’schosenmethodformodelingsourceslessthan50km.Insituationswhereyouareassessingvisibilityimpactsforsource-receptordistanceslessthan50km,youshoulduseexpertmodelingjudgmentindeterminingvisibilityimpacts,givingconsiderationtobothCALPUFFandotherEPA-approvedmethods.Indevelopingyourmodelingprotocol,youmaywanttoconsultwithEPAandyourregionalplanningorganization(RPO).Upfrontconsultationwillensurethatkeytechnicalissuesareaddressedbeforeyouconductyourmodeling.•Foreachsource,runthemodel,atprecontrolandpost-controlemissionratesaccordingtotheacceptedmethodologyintheprotocol.Usethe24-houraverageactualemissionratefromthehighestemittingdayofthemeteorologicalperiodmodeled(fortheprecontrolscenario).Calculatethemodelresultsforeachreceptorasthechangeindeciviewscomparedagainstnaturalvisibility‘8lnferogencyWorkgrouponAirQualityModeling(IWAQM)Phase2SummaryReporfandRecommendationsforModelingLongRangeTransportImpacts,U.S.EnvironmentalProtectionAgency,EPA—454/R—98—019,Oecember1998.conditions.Post-controlemissionratesarecalculatedasapercentageofpre-controlemissionrates.Forexample,ifthe24-hrprecontrolemissionrateis100lb/hrofSO2,thenthepostcontrolrateis5lb/hrifthecontrolefficiencybeingevaluatedis95percent.Makethenetvisibilityimprovementdetermination.Assessthevisibilityimprovementbasedonthemodeledchangeinvisibilityimpactsforthepre-controlandpost-controlemissionscenarios.YouhaveflexibilitytoassessvisibilityimprovementsduetoHARTcontrolsbyoneormoremethods.Youmayconsiderthefrequency,magnitude,anddurationcomponentsofimpairment.Suggestionsformakingthedeterminationare:Useofacomparisonthreshold,asisdonefordeterminingifHART-eligiblesourcesshouldbesubjecttoaHARTdetermination.Comparisonthresholdscanbeusedinanumberofwaysinevaluatingvisibilityimprovement(e.g.thenumberofdaysorhoursthatthethresholdwasexceeded,asinglethresholdfordeterminingwhetherachangeinimpactsissignificant,orathresholdrepresentinganxpercentchangeinimprovement).•Comparethe98thpercentdaysforthepre-andpost-controlruns.Notethateachofthemodelingoptionsmaybesupplementedwithsourceapportionmentdataorsourceapportionmentmodeling.E.HowdoIselectthe“best”alternative,usingtheresultsofSteps1through5?1.SummaryoftheImpactsAnalysisFromthealternativesyouevaluatedinStep3,werecommendyoudevelopachart(orcharts)displayingforeachofthealternatives:(1)Expectedemissionrate(tonsperyear,poundsperhour);(2)Emissionsperformancelevel(e.g.,percentpollutantremoved,emissionsperunitproduct,lb/MMHtu,ppm);(3)Expectedemissionsreductions(tonsperyear);(4)Costsofcompliance—totalannualizedcosts(5),costeffectiveness(S/ton),andincrementalcosteffectiveness(S/ton),and/oranyothercost-effectivenessmeasures(suchas5/deciview);(5)Energyimpacts;(6)Non-airqualityenvironmentalimpacts;and(7)Modeledvisibilityimpacts.2.Selectinga“best”alternative1.YouhavediscretiontodeterminetheorderinwhichyoushouldevaluatecontroloptionsforHART.Whatevertheorderinwhichyouchoosetoevaluateoptions,youshouldalways(1)displaytheoptionsevaluated;(2)identifytheaverageandincrementalcostsofeachoption;(3)considertheenergyandnon-airqualityenvironmentalimpactsofeachoption;(4)considertheremainingusefullife;and(5)considerthemodeledvisibilityimpacts.Youshouldprovideajustificationforadoptingthetechnologythatyouselectasthe“best”levelofcontrol,includinganexplanationofthe

# Federal Register/Vol.

70,

No. 128/Wednesday,

July

6, 2005/Rules

and Regulations

39171 CAA factors

that

led

you

to choose

that option

over

other control

levels. 2.

In the case where

you

are conducting

a BART determination

for two regulated pollutants

on

the same source,

if the result is two different

BART technologies

that

do not work

well together,

you could

then substitute

a different technology

or combination

of technologies. 3.

In selecting

a “best” alternative,

should

I consider

the affordability

of controls? 1. Even

if the control technology

is cost effective,

there

may

be cases where

the installation

of controls

would

affect

the viability

of continued

plant operations. 2. There

may

be unusual circumstances that justify

taking

into consideration

the conditions

of the plant

and

the economic effects

of requiring

the

use

of

a given control technology.

These

effects

would include effects

on product

prices,

the market

share, and profitability

of the source.

Where

there are such unusual circumstances

that

are judged

to affect

plant operations,

you

may take

into consideration

the conditions

of the plant

and

the economic

effects

of requiring the

use

of

a control technology.

Where

these effects

are judged

to have

a severe

impact

on plant operations

you

may consider

them

in the selection

process,

but

you

may

wish

to provide

an economic

analysis

that demonstrates,

in sufficient

detail

for public review,

the specific economic

effects, parameters,

and reasoning.

(We recognize that

this review

process

must preserve

the confidentiality

of sensitive

business information).

Any analysis

may

also consider whether

other competing

plants

in the same industry

have

been required

to install

BART controls

if this information

is available. 4. Sulfur dioxide

limits

for utility

boilers You must require

750

MW power

plants

to meet specific

control

levels

for 502

of either 95 percent

control

or 0.15 lbs/MMBtu,

for each

ECU greater

than

200

MW

that

is currently uncontrolled

unless

you determine that

an alternative

control

level

is justified based

on

a careful consideration

of the statutory

factors.

Thus,

for example,

if the source demonstrates circumstances

affecting its ability

to cost-effectively

reduce

its emissions,

you should

take

that

into account in determining

whether

the presumptive levels

of control

are appropriate

for that facility.

For

a currently uncontrolled

ECU greater

than

200

MW

in size,

but located

at a power

plant smaller

than

750

MW

in size, such controls

are generally cost-effective

and

could

be used

in your BART determination considering

the

five factors specified

in CAA section 169A(g)(2).

While

these

levels

may represent

current

control capabilities,

we expect

that scrubber technology

will continue

to improve

and control

costs continue

to decline.

You should

be sure

to consider

the level

of control

that

is currently best achievable

at the time

that

you

are conducting

your BART analysis. For coal-fired

EGUs

with existing

postcombustion802 

# controls achieving

less

than 50 percent

removal efficiencies,

we recommend

that

you evaluate constructing

a new

FGD system

to meet

the same emission limits

as above

(95 percent

removal

or 0.15 lb/mmBtu),

in addition

to the evaluation

of scrubber

upgrades

discussed

below.

For

oilfired units, regardless

of size,

you should evaluate

limiting

the sulfur content

of the fuel

oil burned

to

1 percent

or less

by weight. For those BART-eligible

ECUs

with

pre existing post-combustion

SO 2 controls achieving

removal efficiencies

of

at least

50 percent,

your BART determination

should consider

cost effective

scrubber

upgrades designed

to improve

the system’s

overall

SO 2 removal efficiency.

There

are numerous scrubber enhancements

available

to upgrade the average

removal efficiencies

of

all types of existing

scrubber

systems.

We recommend that

as you evaluate

the definition

of “upgrade,”

you evaluate

options

that

not only improve

the design removal efficiency of the scrubber

vessel

itself,

but

also consider upgrades

that

can improve

the overall

802 removal efficiency

of the scrubber

system. Increasing

a scrubber

system’s reliability,

and conversely

decreasing

its downtime,

by way of optimizing

operation procedures, improving maintenance

practices,

adjusting scrubber chemistry,

and increasing

auxiliary equipment redundancy,

are

all ways

to improve

average

SO 2 removal efficiencies. We recommend

that

as you evaluate

the performance

of existing

wet scrubber systems,

you consider

some

of the following upgrades,

in

no particular

order,

as potential scrubber

upgrades

that

have

been proven

in the industry

as cost effective

means

to increase

overall

SO 2 removal

of wet systems: (a) Elimination

of Bypass

Reheat; (b) Installation

of Liquid Distribution Rings;

(c) Installation

of Perforated

Trays; (d) Use

of Organic

Acid Additives; (e) Improve

or Upgrade

Scrubber

Auxiliary System Equipment;

(I) Redesign

Spray Header

or Nozzle Configuration. We recommend

that

as you evaluate upgrade

options

for

dry scrubber

systems, you should consider

the following

cost effective upgrades,

in

no particular

order: (a) Use

of Performance

Additives; (b) Use

of more Reactive

Sorbent; (c) Increase

the Pulverization

Level

of Sorbent; (d) Engineering

redesign

of atomizer

or slurry injection

system. You should evaluate

scrubber

upgrade options

based

on

the

5 step BART analysis process. 5. Nitrogen

oxide

limits

for utility

boilers You should establish

specific numerical limits

for NOx control

for each BART determination.

For power

plants

with

a generating

capacity

in excess

of 750

MW currently

using selective

catalytic reduction (SCR)

or selective non-catalytic

reduction (S NCR)

for part

of the year,

you should presume

that

use

of those

same controls

yearround

is BART.

For other sources currently using

8CR

or SNCR

to reduce

NOx emissions during

part

of the year,

you should carefully consider

requiring

the

use

of these controls year-round

as the additional

costs

of operating

the equipment

throughout

the year would

be relatively

modest. For coal-fired

ECUs greater

than

200

MW located

at greater

than

750

MW power

plants and operating

without post-combustion controls

(i.e.

8CR

or SNCR),

we have provided presumptive

NOx limits, differentiated

by boiler

design

and

type

of coal burned.

You

may determine

that

an alternative

control

level

is appropriate

based on

a careful consideration

of the statutory factors.

For coal-fired

ECUs greater

than

200 MW located

at power

plants

750

MW

or less in size

and operating

without

postcombustion

controls,

you should likewise presume

that these

same

levels

arecosteffective.

You should

require

such utility boilers

to meet

the following

NOx emission limits,

unless

you determine

that

an alternative

control

level

is justified

based

on consideration

of the statutory

factors.

The following

NOx emission

rates

were determined

based

on

a number

of assumptions,

including

that

the ECU boiler has enough

volume

to allow

for installation and effective operation

of separated

overfire air ports.

For boilers

where

these assumptions

are incorrect,

these emission limits

may

not

be cost-effective.39172FederalRegister/Vol.70,No.128/Wednesday,July6,2005/RulesandRegulationsTABLE1.—PRESUMPTIVENOEMISSIONLIMITSFORBART-ELIGIBLECOAL-FIREDUNITS.19•NOxpresumptiveUnittypeCoaltypelimit(lb/mmbtu)20Dry-bottomwall-firedBituminous0.39Sub-bituminous0.23Lignite0.29Tangential-tiredBituminous0.28Sub-bituminous0.15Lignite0.17CellBurnersBituminous0.40Sub-bituminous0.45Dry-turbo-tiredBituminous0.32Sub-bituminous0.23Wet-bottomtangential-firedBituminous0.62MostEGUscanmeetthesepresumptiveNOxlimitsthroughtheuseofcurrentcombustioncontroltechnology,i.e.thecarefulcontrolofcombustionairandlowNOxburners.Forunitsthatcannotmeettheselimitsusingsuchtechnologies,youshouldconsiderwhetheradvancedcombustioncontroltechnologiessuchasrotatingopposedfireairshouldbeusedtomeettheselimits.BecauseoftherelativelyhighNOxemissionratesofcycloneunits,8CRismorecost-effectivethantheuseofcurrentcombustioncontroltechnologyfortheseunits.TheuseofSCRsatcycloneunitsburningbituminouscoal,sub-bituminouscoal,andligniteshouldenabletheunitstocost-effectivelymeetNOxratesof0.10lbs/mmbtu.Asaresult,weareestablishingapresumptiveNOxlimitof0.10lbs/mmbtubasedontheuseof8CRforcoal-firedcycloneunitsgreaterthan200MWlocatedat750MWpowerplants.Aswiththeotherpresumptivelimitsestablishedinthisguideline,youmaydeterminethatanalternativelevelofcontrolisappropriatebasedonyourconsiderationoftherelevantstatutoryfactors.Forothercycloneunits,youshouldreviewtheuseof8CRandconsiderwhetherthesepost-combustioncontrolsshouldberequiredasBART.Foroil-firedandgas-firedEGUslargerthan200MW,webelievethatinstallationofcurrentcombustioncontroltechnologytocontrolNOxisgenerallyhighlycost-effectiveandshouldbeconsideredinyourdeterminationofBARTforthesesources.19NoCellburners,dry-turbo-firedunits,norwetbottomtangential-firedunitsburninglignitewareidentifiedasBART-eligible,thusnopresumptivelimitwasdetermined.Similarly,nowet-bottomtangential-firedunitsburningsub-bituminouswereidentifiedasBART-eligible.2°TheselimitsreflectthedesignandtechnologicalassumptionsdiscussedinthetechnicalsupportdocumentforNOxlimitsfortheseguidelines.SeeTechnicalSupportDocumentforDARTNOrLimitsforElectricGeneratingUnitsandTechnicalSupportDocumentfarDARTNOrLimitsforElectricGeneratingUnitsExcelSpreadsheet,MemorandumtoDocketOAR2002—0076,April15,2005.ManysuchunitscanmakesignificantreductionsinNOxemissionswhicharehighlycost-effectivethroughtheapplicationofcurrentcombustioncontroltechnology,21V.EnforceableLimits/ComplianceDateTocompletetheBARTprocess,youmustestablishenforceableemissionlimitsthatreflecttheBARTrequirementsandrequirecompliancewithinagivenperiodoftime.Inparticular,youmustestablishanenforceableemissionlimitforeachsubjectemissionunitatthesourceandforeachpollutantsubjecttoreviewthatisemittedfromthesource.Inaddition,youmustrequirecompliancewiththeBARTemissionlimitationsnolaterthan5yearsafterEPAapprovesyourregionalhazeSIP.Iftechnologicaloreconomiclimitationsintheapplicationofameasurementmethodologytoaparticularemissionunitmakeaconventionalemissionslimitinfeasible,youmayinsteadprescribeadesign,equipment,workpractice,operationstandard,orcombinationofthesetypesofstandards.Youshouldconsiderallowingsourcesto“average”emissionsacrossanysetofBART-eligibleemissionunitswithinafenceline,solongastheemissionreductionsfromeachpollutantbeingcontrolledforBARTwouldbeequaltothosereductionsthatwouldbeobtainedbysimplycontrollingeachoftheBART-eligibleunitsthatconstituteBART-eligiblesource.YoushouldensurethatanyBARTrequirementsarewritteninawaythatclearlyspecifiestheindividualemissionunit(s)subjecttoBARTregulation.BecausetheBARTrequirementsthemselvesare“applicable”requirementsoftheCAA,theymustbeincludedastitleVpermitconditionsaccordingtotheproceduresestablishedin40CFRpart70or40CFRpart71.Section302(k)oftheCAArequiresemissionslimitssuchasBARTtobemetonacontinuousbasis.Althoughthisprovisiondoesnotnecessarilyrequiretheuseof215eeTechnicalSupportDocumentforBARTNOxLimitsforElectricGeneratingUnitsandTechnicalSupportDocumentforDARTNOrLimitsforElectricGenemtingUnitsExcelSpreadsheet,MemorandumtoDocketOAR2002—0076,April15,2005.continuousemissionsmonitoring(CEMs),itisimportantthatsourcesemploytechniquesthatensurecomplianceonacontinuousbasis.Monitoringrequirementsgenerallyapplicabletosources,includingthosethataresubjecttoBART,aregovernedbyotherregulations.See,e.g.,40CFRpart64(complianceassurancemonitoring);40CFR70.6(aj(3j(periodicmonitoring);40CFR70.6(c)(1)(sufficiencymonitoring).NotealsothatwhilewedonotbelievethatCEMswouldnecessarilyherequiredforallBARTsources,thevastmajorityofelectricgeneratingunitspotentiallysubjecttoBARTalreadyemployCEMtechnologyforotherprograms,suchastheacidrainprogram.Inaddition,emissionslimitsmustbeenforceableasapracticalmatter(containappropriateaveragingtimes,complianceverificationproceduresandrecordkeepingrequirements).Inlightoftheabove,thepermitmust:•Besufficienttoshowcomplianceornoncompliance(i.e.,throughmonitoringtimesofoperation,fuelinput,orotherindicesofoperatingconditionsandpractices);and•Specifyareasonableaveragingtimeconsistentwithestablishedreferencemethods,containreferencemethodsfordeterminingcompliance,andprovideforadequatereportingandrecordkeepingsothatairqualityagencypersonnelcandeterminethecompliancestatusofthesource;and•ForEGUS,specifyanaveragingtimeofa30-dayrollingaverage,andcontainadefinitionof“boileroperatingday”thatisconsistentwiththedefinitionintheproposedrevisionstotheNSPSforutilityboilersin40CFRPart60,subpartDa.22Youshouldconsideraboileroperatingdaytobeany24-hourperiodbetween12:00midnightandthefollowingmidnightduringwhichanyfueliscombustedatanytimeatthesteamgeneratingunit.Thiswouldallow30-dayrollingaverageemissionratestobecalculatedconsistentlyacrosssources.[FRDoc.05—12526Filed7—5—05;8:45am]BILLINGCODE65B0—50-P2270FR9705,February26,2005.