AshGroveDurkee&PCMACTGoalsofMeeting•Durkeeplantemissions•NeedforSubcategorization–Technicalrationalefordoingso•Hgcontroltechnologies–Whatworks–Whatdoesn’t•Nextsteps– WhatadditionalinformationdoesEPAneedtomakeatechnicallyandlegallysounddecision?DurkeeHistory•Sept/Dec2006extensivemercurystacktesting•AprilandMay2007ACIpilottesting•Sept2007ODEQStakeholdersfirstmet•Dec2007ODEQissuedstakeholderreport•March2008PublicMeetingonOrder•July2008OrdersignedbyODEQ•Feb2009ConstructioninitiatedonACIsystem•April2010Completesorbenttrapinstallation•StartupACIsystembyJuly2010•Significantreductionswillbeinplace3yearsearlySourcesofMercuryatDurkee•Hgincementplantscomesfrom:–Materialsquarriedonsite•Primarilylimestone•~99%ofDurkeeHg–Fuels•~1%ofDurkeeHg–Additivesimportedfromoff‐site•e.g.,powerplantflyash(notusedbyAshGrove)•~0%atDurkee•Estimated2007emissions:2,163lbsHg•Estimated2008emissions:1,508lbsHg•About2,670poundspermilliontonsofclinkerEnhancedACIRecirculationSystemHg0outScrubberHeatExchangerHeated Area (800°F)CarbonCarbonStorageTankHg laden exhaust(266°F/412°F)CarbonClean gasCarbon/Raw Material BleedWaterWaterMAINSTACKHg CMSHg CMSACI BaghouseTankMakeupWaterMakeupcarbonInert Gas +Hg vaporHg SettlingTankInert Gas (N2) MakeupAir lockMercuryConsiderations•Hglevelsinlimestonevarywidely–Durkeemonthlyaveragelimestonerangesfrom424ppbto1,740ppb•Samplesgatheredbetween2006and2009•Hgformsvarywidely–ElementalHgcanaccountformorethanhalfoftotalHg•Hgconcentratesinsystemy = 2.089x + 135.67R2= 0.4337y = 2.2303x + 345.31R2= 0.6171-100200300400500600- 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.0Time, hours

ug/dscmElemental HgTotal HgHg CEM Data (Raw Mill On)MercuryTransformation•OxidizedHgcapturedinrawmillandre‐enterskilnascomponentofkilnfeed•Feedattopoftower(800oF)volatilizesHginprimarilyelementalform•Amountandrateofconversiontooxidizedformdeterminedbygasconditionsintower,withsubsequentrecapturebyrawmillAshGroveResearch•1monthpilotstudy•Hgcontrol(relative)MercuryTypeRaw MillOnRaw MillOff% ControlRaw MillOnElemental 209.2 354.5 40.99%Oxidized 214.6 2752.8 92.20%Total 423.9 3107.3 86.36%ug/dscm ug/dscmAshGroveCommitment•AshGrovesignedOrderwithOregonDEQinJuly2008–RequiresbyJuly2010:•Minimum75%Hgcontrol•Allreasonableeffortstoremove85%ofHg–WoulddecreaseHgemissionsto:•670lb/MMtonclinkerat75%control•400lb/MMtonclinkerat85%control–Controlsinconstruction•Willremoveabout2.8tonsofHgbeforeNESHAPHgstandardsrequireanyreduction–Assuming2007production/emissionlevelsPortlandCementMACTProposal•EPArecognizedDurkeecontrolsas“thebestcontroltechnologycurrentlyavailablesofarasisknown”–EPArecognizedthatimportinglimestoneisimpracticalforplantslikeDurkee–MeansDurkeemustrelyoncontrols–ACIwillnotreach43lb/MMtonclinker•Wouldrequire99%SRE•Basedonthepilottestresults,EERCandODEQstakeholdercommitteerecommended75%controlConstructionUnderwayonDurkeeACISystemDurkeeCarbonTrapSystem• Tectonicactivity• Createdbeltwherethereisenhancedgeothermalhistory• GeothermalactivityisbestindicationofHgWhyisOregonLimestoneDifferent?5075100125150Net U.S. Cement Supply Balance(million metric tonnes)Source: Portland Cement AssociationU.S.cementsupplyisalreadypredictedtobeunabletomeetfuturedemandevenwithoutplantclosuresGreen=DemandRed=U.S.SupplyGlobal CementManufacturing:•2.75 billion tons per year,with majority in rapidlyexpanding developingnations, primarily China and India•Worldwide demand for cement ispredicted to grow by 50to 80% in the next 20 yearsWesternU.S.demandthatcannotbemetdomesticallywillbesatisfiedbyimportsfromAsiaExistingPacificCementImportInfrastructure18Pacific Coast hasstrong populationand economicgrowth andcement supplyimbalance.None of theplanned plantmodernizations isfor Pacific coastalregion, due torole and threat ofimports.ImportedCementResultsinGreaterEmissions•EnvironstudyfoundthatcementimportedfromChinatoCaliforniahas~50%greaterCO2emissionsthandomesticcement–StudyassumedthatChineseandU.S.cementplantsareequallyefficientandequallywellcontrolled•Thesemaynotberationalassumptions–DifferenceinemissionsattributablesolelytoelectricityusageandmovingcementfromChineseplanttoU.S.portEmissionsFromCementImports•EmissionsofpollutantssuchasSO2,PM2.5andNOxalsohigherforimportedcement•ShipsbringingcementfromPacificRimcountriesburnbunkerfuelwithupto5%sulfur–Averagesulfurcontentincargoshipfuel=27,000ppm–U.S.truckscannotusedieselwithmorethan15ppmsulfur•Shipsburnfuelwithover1,800timesmoresulfurpergallonthanallowedinfuelusedbyaU.S.truck•ShipfuelhasmuchhighernitrogencontentresultinginmoreNOxemissions•SO2andNOxresultinmorePM2.5emissionsUnintendedConsequencesofNotProvidingaTechnicalOption•Durkeeplantprovides:–116directjobsinBakerCounty•Sixdifferentunionlodgesrepresenthourlyworkforce•>$9,000,000peryearpayrollandbenefits–Numerousindirectjobs•Operatingbudgetisinexcessof$40,000,000•Capitalbudgetnormallyexceeds$3,000,000annually–~$1million/yearinpropertytaxes–SubstantialcontributortolocalcausesSolution:>225ppbSubcategory•CleanAirActallowsEPAtocreatesubcategorieswithdifferentstandards:–“TheAdministratormaydistinguishamongclasses,types,andsizesofsourceswithinacategoryorsubcategoryinestablishingsuchstandards...” CleanAirAct§ 112(d)(1)–“TheconcurringopinioninBrickMACTsupportssubcategorizationinsituationsinvolvingsources’dependenceonhigh‐HAPrawmaterialstoavoidsituationswherealevelofperformanceachievedbysomesourcesprovesunachievablebyothersourcesevenafterapplicationofbesttechnologicalcontrols,viewingsuchsourcesasofadifferenttypethanothersinthesourcecategory.” EPAPreambletoProposedRule(p.21148)SubcategorizationAccordsWithCommonSense•BrickMACTdecision:“onelegitimatebasisforcreatingadditionalsubcategoriesmustbetheinterestinkeepingtherelationbetween‘achieved’ and‘achievable’ inaccordwithcommonsenseandthereasonablemeaningofthestatute.”SubcategorizationAccordsWithCleanAirAct•CongressclearlystatedthatEPAshouldnotrequiresubstitutionofminedfeedstocks insettingNESHAPstandards[Conf.Comm.Report]:“thesubstitutionofcleanerorestockswasnot,inanyevent,afeasiblebasisonwhichtosetemissionstandards...[where]metallicimpuritylevelsarevariableandunpredictablebothfromminetomineandwithinspecificoredeposits.”–ThisquotesumsuplimestonequarriesMACTisNOTIntendedtoShutDownSourcesCongress’ intentinrelationtosubcategorizationissimilarlymadeclearintheHouseReportassociatedwiththe1990Amendments.TheHouseReportstatesthat:“ TheCommitteeexpectsMACTtobemeaningful,sothatMACTwillrequiresubstantialreductionsinemissionsfromuncontrolledlevels.However,MACTisnotintendedtorequireunsafecontrolmeasures,ortodrivesourcestothebrinkofshutdown.” HouseRep.No.101‐490,Part1at328(May17,1990)(emphasisadded).Subcategorization•Subcategorizationforsourceswith>225ppblimestone•Floorbasedoncurrent,uncontrolledemissionsfromthetwoplantsinsubcategory•EPAcouldthenimposea“beyondthefloor”standard–Technologybasedlimit–Workpractices•TotalreductionsatDurkeewillbesubstantialandcouldreachashighas90%–90%control=267lb/MMtonclinkerBeyondtheFloorTechnology•ACI–BesttechnologyforaddressingmixofHgforms•WetscrubberdoesnotworkforelementalHg–Onlytechnologythatworksforaridareas•TehachapiandDurkeeinveryaridareas•AnnualrainfallinDurkeeis~8inchessowetscrubbernottechnicallyfeasibleBeyondtheFloorTechnology•ACI–Require75%minimumSRE•SREstandardappropriateforbeyondthefloortechnology–Technologymayoutperformthislevel•Toouncertaintosetstandardat85%SRE–Solution:RequireControlEnhancementActionPlan•AshGrovecommittedtoallreasonablemeasurestoreach85%controlBeyondtheFloorWorkPractices•MinimizeHgenteringsystem–RequireMercuryMinimizationPlan•IdentifyandminimizeHginoff‐sitematerials–Prohibituseofflyashinrawfeed•NotcurrentlyusedbyDurkeeDustShuttling•AshGroverecognizesbenefitsofmaximizingdustshuttling(aka,rawmealpurge)–Wastingbaghousedustnotappropriate–Shuttlingbaghousedusttofinishmillhasgreatpromise–Cannotberequiredabovelevelswhereproductproduct specificationwouldnotbemet•CreatesqualityissuesifoverusedWhataretheSpecificRestrictionstoDustShuttling?MostDOTs donotsupportASTMC1157Cements.Florida,Oregon,Washington,Idaho,andNevadadonotallowC1157cementsforDOT projects.MontanaonlyallowsC1157forroadbase.There are Four NationalCement SpecificationsPerformance Std.Portland CemePortland CemeType IP and IS Type GU cementsASTM C150 AASHTO M-85 ASTM C595 Blended ASTM C1157Insoluble Residue 0.75%, Max 0.75%, Max IP = no limit, IS = 1% No LimitLOI, limit 3.00% 3.00% IP = 5% max, IS = 3.0% No LimitLimestone Addition 5% Max 5% Max Not defined No LimitProcess Additions 5% Max 5% Max No limit, Use C465 comparisons No LimitActionItemsfromFebruary11,2009MeetingwithFDEP(Linero),CementIndustry,Consultants(Dr.GregMiller),andFDOTThefocuswastodiscusstheoptionsavailabletotheCementIndustrytolimitmercury(Hg)emittedduringtheclinkeringprocess.MeetingActionItems:•“Cementindustrytotryandutilizefilterdustbackintothecementproduct.”•“FDOTwillassistwithtestingthe‘new’ cementtoverifyingcompliancewithM‐85.TheDepartmenthasagreedthatthefilterdustisoktouseaslongasthecementcontinuestocomplywithAASHTOM‐85.”•“Oncethenewcementisavailable,theFDOTwillconductteststo verifydurabilitytestsinhopesthatthehighalkali,highHgcementisnotdeleterioustoourconcreteorreinforcingsteel.”•“DEPindicatedthatthenewrestrictionsonHgemissionshaveatargetdeploymentdateofMarch31,2009.Howeverthestandardsmaybeimplementedpriortoorafterthisintendedimplementationdate.”2005PortlandCementShipmentsInformation from USGS 2005 Minerals YearbookDustShuttling•AASHTOandASTMstandardsallowupto5%inorganicprocessingadditions•Cementmuststillmeetotherspecs–Insolubleresidue:≤0.75percent–Lossonignition:≤3.0percent–Limestoneaddition:≤5percent•BasedonCO2content–Processaddition:≤5percent•ExtensivedebateastowhatthiswilltranslatetoatanyindividualplantMercuryReductionPatents•Heidelberg’spatentapplication–German(only)patentpending(Feb2007)•TaiheiyoCementCofiledpatentapplicationfiledinJapan(Sept2004)•AshGrovefiledpatentapplicationinUS(March2008)•Status–Patentspending–Protectivefilings–Technicaldetailsaresparse–Notyetdemonstratedinlongtermpracticeandnocaptureefficienciesclaimed–EuropeanandJapanesecementstandardsaredifferentthanU.S.DustShuttlingatDurkee•Baghousedusthascalciumcarbonatesoitwilltestaslimestoneandthemaximumadditionrateis5%•At5%additionratetheinsolubleresidueis1.22%–BHdusthas20%silicaandaIRofabout18%–Maximumdustis2.14%toachieve0.70IR•BHdustis35%LOIsoadding4%wouldraiseacementwith1%LOIto2.5%LOI•InsolubleresiduelimitsBHdustadditionto2.14%DurkeeBaghouseDustConcentrationDuringPilotTestDurkee’s MaximumAdditionRate•Clinkerproduced– 900,000tons•Clinkershippedtogrindingoperation– 300,000tons•CementproducedatDurkeewithclinkerandgypsum–630,000tons•Dustshuttledat2.14%– 13,482tonsor2.0tph whentherawmillisrunning.•Potentialmercuryreductionis404poundsor15%•Thisleaves2223poundslefttoreducetomeettheproposedstandardora98.1%reduction•Wecan’tbutWHATifwecouldreduceitby30%?–1819poundstoreducetomeettheproposedstandardora97.7%reductionQuestion?Howmanycontroltechnologiesinstalledonacementplantcanachieve98%controloveramonthlyrollingaveragingperiod?DustShuttling•Degreeofbenefitsnotclear–Lehighbelievesitcouldreach30%SREatUnionBridgeplant•UnionBridgebaghousedustaverages25ppmHgduringrawmilldownconditions•ResultofhighrelativepercentageofoxidizedHg?•UnionBridgeshowshigherHgconcentrationinbaghousedustthanotherLehighplants(Frome‐mailTimMatztoKeithBarnett)DustShuttling•TehachapidatasuggestingUnionBridgecontrolefficiencyisnottransferrable–Tehachapi:VastmajorityofHgiselementalandbaghousedustHgconcentrationstypically<10ppm–TehachapiHgconcentrationinrawfeedis400%ofUnionBridge–TehachapiHgconcentrationinbaghousedustis40%ofUnionBridge(Frome‐mailTimMatztoKeithBarnett)DustShuttlingConclusions•Dustshuttlingclearlyholdsgreatpromise•Degreeofbenefitvarieswithsite‐specificcharacteristics–Notallvariablesfullyunderstood•Percentageofbaghousedustthatcanbeusedinfinishmillcanbedefinedbyobjectivetests•PercentageofbaghousedustthatcanbeusedinfinishmillwillvaryplanttoplantDustShuttlingConclusions•Inlightofuncertainty,don’tlosetrackofgoal–Workpracticerequiringmaximumreductionratherthanaspecifiedemissionrate•Requireuseofdustshuttling–Uptolimitofwhatcanbeaccomplishedwithoutimpairingcement’sabilitytomeetqualitystandards•RequiredocumentationofshuttlingmaximizationOtherSuggestedTechnologies•SelectiveQuarrying•SCR•Limestonescrubbing•CKDtreatment‐Roasting????SelectiveMining•Somecommenters suggestedpossibilityofselectiveminingtoavoidHginrawfeed•ExtensiveAshGroveresearchatDurkeequarry•VariabilityinHgconcentrationthroughoutthequarry–NomeansofpredictingareasofhighconcentrationWhatCausesVariability?•Platetectonicmovementhasdisruptedoriginalpositionandcompositionofrocksthroughfolding,fracturing,igneousactivityandmetamorphism•Secondarystructuressuchasfractures,faults,andfoldscausedbyplatemovementcreatedpreferentialpathwaysforgeothermalfluidsandgasestoinfiltrateoriginalhostrock•GeothermalactivityassociatedwithmineraldepositssuchasHgDurkeeQuarryGeology•GeologicallyComplex–Limestonedepositshaveundergoneextremedeformationsincefirstdeposited•Severelyfolded,fracturedandfaulted•Multiplefaultswithsignificantstratigraphicoffsets•Lackofstratigraphic continuity–QuarryisinanareaofanactivehydrothermalventMain Limestone QuarryQuarryBenchFaces‐NelsonMarbleBench 1Bench 2Bench 3Typically 45’ ThickMercuryDistributioninQuarry•Benchblastsfrom2006‐2009havebeencorrelatedtoHgdistribution–Unpredictabledistributionacrossbenches–Unpredictabledistributionwithinindividualshots(3895’ map)–2006‐2009benchblastmapexhibitscheckerboarddistributionofHgconcentrationsMercury Distribution With Blast Layouts●Tremendous Hg variationwithin just a few feet●Not predictable so cannotbe mined aroundSelectiveMiningConclusions•Hgconcentrationsnotpredictable–Rangefrom424ppbto1,740ppb•NotpracticaltominearoundHgasithasnoidentifiablepockets•Lowestvaluefoundinquarryisstilloutofrangeofotherplants•DCCircuitpreviouslystatedoreswitchingisnota“predictableandconsistentcontrolstrategy” [CopperSmelterMACTdecision]AdditionalControlOptionsRaisedinComments•Serialwetscrubber–Sameissueasprimarywetscrubber:Nowater–WetscrubberdoesnotworkontheelementalHgwhichisthechallengeforACI•CEM&stacktestdatashowhighlevelsofelementalHg•OxidationTechniques–SCR•WeknowofnoevidenceitenhancesHgconversiontooxidizedformanybetterthanACI–EERCtriedseveralexoticcarbonsatDurkeeFullscaleACITestatDurkeeShowCaptureRateofOxidizedandElementalareSimilarAGCC Du May 10, 20070500100015002000250030003500400045005000 0 : 0 0 0:45 2 : 5 5 3 : 4 0 4 : 3 0 5: 1 5 6:00 6 : 4 5 7 : 3 5 8 : 2 0 9:05 9 : 5 7 10:42 11:27 12 : 2 0 1 3 : 0 5 1 3 : 5 0 14:3 5 15:2 5 16:10 16 : 5 5 17:40 1 8 : 3 0 1 9 : 1 5 2 0:00 21 : 2 5 22:10 22: 5 5Time hh:mm

TOTAL Hg ug/Nm3 @ 7% O2080160240320400480560640720800 ELEMENTAL Hg ug/Nm3 @ 7% O2 RM StatusTotalAve TotalElementalAve Ele.RM StatusAve Elemental Hg: 266 ug RM DownAve Elemental Hg: 90 ug with PAC = 66% reductionAve Total Hg: 2715 ug RM DownAve Total Hg: 1129 ug with PAC = 58% reductionRaw Mill OffPAC Injection OnAdditionalControlOptionsRaisedinCommentsMercuryRoasterThe information contained or referenced in this presentation is confidential and proprietary toFLSmidth and is protected by copyright or trade secret laws.Mercury RoasterBaghousedustQuenchQuenchSorbentTo stackTofinishmillCleanDustto siloCalciumchlorideHeat source(bypass,Cooler, HGG)Keypoints•WillnotcontrolbetterthanDurkeesystembecausewetreattheentiregasstream•IncreasesheatconsumptionandCO2emissions•MaybegoodwhensmallerreductionsarerequiredBestBeyondtheFloorPackage•>225ppbsubcategorymustinstallACI–75%minimumSRE–ImplementControlEnhancementActionPlantomaximizebenefitsofACI•Requireallreasonablemeasurestomaximizeperformance•RecurringassessmentofwhetherSREexceeds85%–Dutytoreassessinjectionratesandotherreasonablemeasures•Ensurescontinuousimprovementeffortstoreach85%BestBeyondtheFloorPackage•ReduceHgenteringcyclefromoffsitematerials–RequireMercuryMinimizationPlan•Prohibituseofflyashinrawfeed•EvaluateandminimizeHginotherimportedmaterials•Requiredustshuttlinguptomaximumlevelachievablewithoutimpactingproductquality–Requiresitespecificevaluation:•Documentmaximizationofshuttling•DocumentoptimaltimingofdustbleedBestBeyondtheFloorPackage•Couldresultin90%+SRE–Untiloptimizedatindividualplant,notclearwhatcombinationcanachieve–ThisapproachputsemphasisonoptimumpossibleHgreduction–If90%isachieved,Durkeewouldbe~267lbHg/milliontonclinker•Hugereduction•IncrementaladditionalreductionsunlikelyBestBeyondtheFloorPackage•ThisapproachenablesAshGroveto:–CommenceHgcontrol3yearsearlierthanfederalMACTstandards•About2.8tonsadditionalmercuryremoved–Employ“thebestcontroltechnologycurrentlyavailablesofarasisknown”–EmploytheonlycontroltechnologyknowntobeeffectiveonallformsofHg–KeepjobsintheU.S.–AvoidemissionsassociatedwithimportedcementConclusions•Proposedresolutionensures:–Protectionofenvironment–CompliancewithCleanAirAct–Protectionofjobsandcommunity•Avoidsoffshoring jobstocountry’swithpoorercontrols•IfplantssuchasDurkee&Tehachapiclose,theWesternU.S.willmeetcementdemandthroughimports•WhatisEPAthinkingonapproach?•WhatadditioninformationdoesEPAneed?•NextstepsQuestions?