report b integrated oil sands tailings treatment technologies march 2010.pdf

Part B Report

A Screening Study

of

Oil Sand Tailings Technologies and Practices

Prepared for

Alberta Energy Research Institute AERI Contract 2008 0326

REVISION I. March 2010

By

David W. Devenny PhD P Eng P Geol The Rock Doctor March 2010

PartB:OverviewofOilSandTailings

TheRockDoctorB:ExecutiveSummaryPagei

ExecutiveSummaryPartBReport.

ThePartBReportisanoverviewofoilsandstailingspracticesandrelatedtopics.

Thereportstartswithanoverviewofregulatorymattersandthegoverningfiscalregime.Thesehaveasignificantimpactontheprojectdirection,economicsanddecisionmaking.

TheEvolutionofOilSandTailingsreviewsthehistoryoftailingspracticeandhowitresultedintodaysunfortunateinventoryofstrandedfluidtailings.Italsorecognizestheeffectofworldopiniononoilsands.FinallyitdescribesERCBDirective074thatseeksanewdirectionintailingsmanagement.

Thenextsectionprovidesastepbystepdescriptionoftailingstechnologyandpractices.Itreviewswhyfluidtailingsarecreated,containmentrequirements,dewateringrequirementsrequiredtocreatesolidtailings,andtechnologiesthatareavailabletodensifyfluidtailings.Overviewsofoilsandgeology,materialpropertiesandbehaviour,providebackgroundknowledge.

Abriefsectiononworldtailingspracticenotesthatsomeminesprefertotakeshorttermprofits,accumulatefluidtailings,anddeferreclamation.Stockpilingtailingsoftencreatesunnecessaryrisk,andmaybemoreexpensive.Deferringreclamationtransfersreclamationcoststofuturegenerations.Themainreasonforthissectionistoprofilethepoorimageofindustriesthatengageindeferralpractices.

Chapter13reviewsproceduresusedtoscreenoptionsfortailings.Traditionaleconomicanalysisofferspoorguidanceforoilsandprojects.Discounting,overthelongtimespansassociatedwithoilsandsprojects,reducesfutureobligationstoafractionoftheirrealvalue.Distortiondoesnotoccurifreclamationobligationsarebookedastheyarecreated,insteadofwhenfundsarespenttocorrectthem.Recognitioncanbeaccomplishedbydepositingfundsofequivalentvalueinanenvironmentaltrustwhentheobligationiscreated.Addedbenefitsoftheenvironmentaltrustapproachdepositsarerecognizedoperatingcosts.Thatcausesgovernmentstoshareintheexpense.Inadditiontrustdepositsoffsetanautomaticreductioninassetvalue.Finally,theapproachencouragesmanagementthatismorecompatiblewithpublicexpectations.

Informationonoilsandsprojectplans,technologies,andperformanceislimited.Greatertransparencyisneeded.

Thereviewcloseswithanoverviewofoilsandresearchpractices,andrecommendstopicsthatshouldbeexplored.

Appendicessupportthemaintext.Appendix1provideselectronicmodels.Thefirstsummarizesalllifecycleworkandtheassociatedcostdifferencesfordifferenttailingstechnologies.Thesecondoffersaneconomicmodeltoappraisethefulllifecycleofanintegratedoilsandplant.Thethirdisatailingsforecastmodel.Allmodelsallowuserstoinputtheirownvaluessotheimpactofdifferentinputcanbeobserved.Appendix4focusesonmaterialpropertiesandbehaviouranessentialpartofunderstandingtailings.

ReportB:OverviewofOilSandTailings

The Rock DoctorOverviewofOilSandTailingsPageii

TableofContents

# # Title PageB ExecutivesummarytoReportB i Tableofcontents ii

B.1 Introduction 1B.2 Regulatingoilsands B.2.1 Background 4 B.2.2 Albertaenvironmentalprotectionandenhancementact 4 B.2.3 ERCBmandate 4

B.3 Fiscaltermsforoilsands 5B.4 Evolutionoftailingsandreclamationpractices B.4.1 Earlyhistory 6 B.4.2 The1990s 6 B.4.3 Recentevents 8 B.4.4 500ducks 10 B.4.5 ERCBdirective074 11

B.5 OilSandsGeology B.5.1 Resourcebasemineablearea 12 B.5.2 BedrockGeology 12 B.5.3 LocalStructure 12 B.5.4 Originofthebitumen 14 B.5.6 SurficialGeology 14 B.5.7 Orebodycharacter 14

B.6 Miningoilsands 16B.7 Extraction 19B.8 BasictailingsfromextractiontoMFT B.8.1 Introductiontotailings 22 B.8.2 Theoilsandstailingscycle 22 B.8.3 Transportingtailings 24 B.8.4 Tailingssanddeposits 25 B.8.5 Behaviourinthetailingspond 27 B.8.6 Predictingthevolumeoftailings 28

B.9 TailingsDams B.9.1 Introductiontotailingsdams 30 B.9.2 Constructionwithoverburdeninsteadofsand 32 B.9.3 Constructingretentionfacilitiesinpit 33

B.10 ProcessestodensifyMFT B.10.1 Directtreatmentprocesses 34 B.10.2 BehaviourasMFTdensifies 35 B.10.3 Mechanicalprocesses 35 B.10.4 Naturalprocesses 37 B.10.5 MixturesCTandNST 38


The Rock DoctorOverviewofOilSandTailingsPageiii

# # TableofContents(continued) PageB.11 StoringMFTunderawatercap

B.11.1 Permanentstorageunderawatercap 42 B.11.2 Theendpitlake 44

B.12 Worldtailingspracticeandimage 45B.13 Screeningtechnologyoptions

B.13.1 Introduction 47 B.13.2 Characteristicsofoilsandprojects 47 B.13.3 Stepsusedtoscreentechnologyoptions 48 B.13.4 Characteristicsofeconomicanalysis 48 B.13.5 Resultsofscreeningstudies 50 B.13.6 Conclusionsonscreeningoptions 52 B.13.7 QualifyingEnvironmentalTrusts 53 B.13.8 Assigningvaluetofuturereclamationobligations 53

B.14 OilSandTailingsR&D B.14.1 IntroductiontotailingsR&D 54 B.14.2 IncentivefortailingsR&D 54 B.14.3 SuggestedprojectgoalsfortailingsR&D 55 B.14.4 CharacteristicsoftailingsR&D 55 B.14.5 Largescaletailingstechnologyresearch 58 B.14.6 Independentresearch 58 B.14.7 Anillustrationofdifficultyintegratingindependentresearch 59 B.14.8 Effectivenessofoilsandsresearchprograms 61

B.15 SummaryandConclusions V.15.1 Aboutprojectsandpractice 62 B.15.2 ERCBDirective074 62 B.15.3 Aboutmaterialproperties 62 B.15.4 Buildingtailingsdeposits 62 B.15.5 Howtolimitfluidtailings 63 B.15.6 Propertiesoffluidtailings 63 B.15.7 Directmethodsfordensifyingfluidtailings 63 B.15.8 PasteandMixedSoilCasesCTprocess 64 B.15.9 StoringMFTunderawatercap 64 B.15.10 EconomicscreeningofProjectOptions 64 B.15.11 FiscalTerms 65 B.15.12 ResearchandDevelopment 65 B.15.13 InsularCharacter 65

B.16 Closure 66


The Rock DoctorOverviewofOilSandTailingsPageiv

TableofContents(continued) Table# ListofTables PageTableB.1 Characteristicsofthreemineableoilsandprojects 2TableB.2 LanduseattheSyncrudeMildredLakeFacility 3TableB.3 AverageoreusedinthePartAStudy 15TableB.4 Forecastpropertiesoftailingssanddeposits 27TableB.5 Highlightsofinformationobtainedfromthetailingsforecastmodel 28TableB.6 Typicaldimensionsoftailingsdams 30TableB.7 HighlightsoftheJackpinesurfacetailingspond 30TableB.8 Additionalcostwhenoverburdenisusedtobuildtailingsdykes 32TableB.9 RelativevolumesintheCTprocess 39TableB.10 ConcernswiththeCTprocessingoption 41TableB.11 Traditionaleconomicassessmentofcostsvstimeeffectandimage 46TableB.12 Effectofrecognizingreclamationliabilitiesasincurredeffectandimage 46TableB.13 Characteristicsofmineableoilsandprojects 47TableB.14 Typicaltimelineforsiteuse 47TableB.15 Typicalstepstoscreentechnologyoptions 48TableB.16 Threeeconomicscreeningmethodsusedtoevaluatetailingsoptions 49TableB.17 Assigningacosttoreclamationobligations 53TableB.18 SuggestedprojectgoalsfortailingsR&D 55TableB.19 Typesofoilsandtailingsresearch 56TableB.20 Researchplayers,roleandsourceoffunding 56TableB.21 R&Dfunding 57TableB.22 Majortailingstechnologiesstudiedinlargescalefieldpilotprograms 58

ListofFigures

Figure# Title PageFigureB.1 HowAlbertasoilreservesrankwithworlddeposits 1FigureB.2 SatelliteviewoftheSyncrudeandSuncorBasePlants 3FigureB.3 Fiscalsharingvs.priceofoil 5FigureB.4 AerialviewSyncrudeMildredLakeSite 7FigureB.5 Proposaltocapweaktailings 9FigureB.6 MFTinventorytodate 9FigureB.7 Oilonthesurfaceofatailingspond 10FigureB.8 BedrockoftheMineableOilsandsArea 13FigureB.9 400tonminetruck 16FigureB.10 Loadinga400tonhaultruck 17FigureB.11 HowminingandtailingsworkinpitatSyncrude 18FigureB.12 Simpleextractionprocessflowsheet 19FigureB.13 ERCBbitumenextractionrecoverycurve 20FigureB.14 Theoilsandtailingscycle 23FigureB.15 Volumechangeonthepathfromoretowaste 23


The Rock DoctorOverviewofOilSandTailingsPagev

Figure# ListofFigures(continued) PageFigureB.16 PreparationofaconstructioncellatAlbianSands 25FigureB.17 Dozercompactingsandinaconstructioncell 26FigureB.18 Depositingconventionaltailings 27FigureB.19 Crosssectionofatailingsdamcentrelineconstructionmethod 31FigureB.20 Crosssectionofatailingsdamupstreamconstructionmethod 31FigureB.21 Changeindykedesignifconstructedofoverburden 32FigureB.22 Changeindesignifmaterialissolidvs.fluid 33FigureB.23 RelativevolumeofmineralsolidandwaterinMFT 34FigureB.24 Ternarydiagramforcharacterizingbehaviourofsoilslurries 40FigureB.25 Suggestedoffsettoprotectagainstlongtermgulleyerosion 43FigureB.26 Effectofdiscountfactorandtime 49

ListofAppendices

Appendix# Title Appendix1 Electronicdata,spreadsheetsandmodels 1. Workandcostsheetsforeachtechnologystudiedcontaining:

Workactivityvstime Capitalandoperatingcostvstime Reclamationactivitiesvstime Massbalances Userdefinedinputforcapitalandoperatingcosts Comparisonofunitcostforthetailingstechnologiesstudied

2. Fullprojecteconomicmodelthatconsiders Userdefinedinputfor

o Capitalconstructioncosto Productionvstimeo Incomefromproductsaleso Operatingcosts

Fiscalregimeconsideringroyalty,capitalallowances,provincialandfederalincometax

Inputforcapitalandoperatingcostforspecifictailingsoptions Treatmentofreclamationliabilities

Traditional(ignore),offsetagainstassetvalue,fundaQET. Cashflowtothedeveloper,provinceandfederalgovernment Rateofreturnfortheprojectandthedeveloper

3. TailingsforecastmodelUserinput Orecharacter Materialproperties Plantvariablesfinesdispersion,dischargedensityOutput Wastedepositssandandfluidtailsvolumes Waterlosshotwaterandoverallwaterloss


The Rock DoctorOverviewofOilSandTailingsPagevi

Appendices(continued) Appendix2 Drytailscase Appendix3 Definitions Appendix4 Materialpropertiesandbehaviour Appendix5 SuggestionsfortailingsR&D

B.1OilSandsBackground

The Rock Doctor B.1OilSandsBackground Page1

B.1IntroductionThissectionprovidesbackgroundinformationaboutAlbertasoilsands.Allinformationisfrompublicsources.

Theoilsandsareaworldclasssourceofoil.FigureB.1showshowtheresourcecompareswithotherworldsupplies.Somefactsabouttheresource

Resourcebase 1.7trillionbarrelsProvenreserves 170billionbarrelsrecoverableusingtodaystechnologyShallowmineable 35billionbarrelsProduction(2008) 1.3millionbarrelsperday Outlook 3millionbarrelsperdayby2018

FigureB.1HowAlbertasoilsandsrankwithworlddeposits.(AlbertaEnergy,2008).

Halfoftheoilsandproductioncomesfromshallowdepositsthataremined,thebitumenextractedusingahotwaterprocessandupgradedtoapipelineableproduct.

CharacteristicsofthreeoilsandprojectsaresummarisedonTable1.Theprojectsallstartedbigandaregettingbigger.Allhaveplanstoexpandtoproducehalfamillionbarrelsperdayinthenextfewyears.Syncrude,now30yearsold,expectstolastfor100years.



TableB.1Characteristicsofthreemineableoilsandsprojects.

Project/Component Suncor Syncrude AlbianSandsStartupdate 1967 1978 2002Yearsinoperation 43 32 8Configuration Integratedfacility

MineMineWastedisposalExtractionUpgradingUpgraderTankfarmUtilitiesTailingsponds

IntegratedfacilityMineMineWastedisposalExtractionUpgrading

UpgraderTankfarm

UtilitiesTailingsponds

SeparatefacilitiesAtsiteMineExtractionWastedisposal455km24dilutedbitumenand12diluentreturnline.UpgraderatScotford(nearEdmonton)

Satellite MineandextractionsatellitesnearbyRemoteInsitu

Largesatellitecontainsmine,extraction,tailings

Expandingonsite

Startupproduction 45,000bblSCO/day 105,000bblSCO/day 150,000bblSCO/dayCurrentproduction 260,000bblSCO/day 300,000bblSCO/day 150,000bblSCO/dayPlannedproduction 500,000bblSCO/day 500,000bbl/day 500,000bbl/dayExtractionprocess Hotwater

UseNaOHdispersantHotwater

UseNaOHdispersantHotwater

Originallynodispersant.NowuseNaCitrate.Thickenerforheat

recovery.Extractionefficiency% 92% 90.7%

80%

(afterasphalteneloss)Upgradingyield 84% 87.5% 100%Cokeproduction 2milliontonnes/year 2.5milliontones/year Asphaltenesarerejected

andaddedtotailingsTailings ConventionalMFT

followedbyCTConventionalMFTfollowedbyCT

Producethickenedtails.LessMFTbecausenot

usingdispersant.GreenhouseGasTonnes/m3SCO

0.6 0.85 NA

VOCemission(kg/m3) 1.73 NA NANaphthaloss NA .0043bbl/bbl NAEnergyuseGJ/m3SCO 7.4 8.1 NAWaterimportm3/m3 2.4 2.03 NAWaterrecycle% N/A 88% NACumulativedisturbanceha 13,093 21,282 NACumulativeareareclaimed

949 4,668 NA

ReclamationCertificateha

0 104 0



FigureB.1isanaerialviewofthebaseplantsforSyncrudeandSuncor.TableB.2summariseslanduseattheSyncrudebaseplant.Openpitmines,wastedumpsandtailingsfacilitiesdominatethelandscape.Thefootprintisjustundertwotownships.

TableB.2LanduseattheSyncrudeMildredLakeFacility(BasePlant) Landuse/area Ha %

Plantsiterelated 550 3%Mining Openpitspace 4,250 25% Overburdenwastedumps 1,100 6%Tailingspondsandrelatedareas 6,400 38%Miscellaneous 4,700 28%Total 17,000 100%

FigureB.2SatelliteviewofSyncrudeandSuncorbaseplants

B.2RegulatingOilSands

TheRockDoctorB.2RegulatingOilSands Page4

B.2.Regulatingoilsands B.2.1 Background OilSanddevelopmentisregulatedinAlbertabyAlbertaEnvironment(AENV),theEnergyResourcesConservationBoard(ERCB)andAlbertaSustainableResourceDevelopment(SRD).TheFederalgovernmentmanagesitsrolethroughEnvironmentCanadaandtheDepartmentofFisheriesandOceans.AENVandSRDhaveprimaryresponsibilityformanagingtheenvironment.Thatincludes,pollutionpreventionandcontrol,waterallocation,useandprotectionofpotablewater,conservationandreclamationplanning,andtheevaluationofair,water,andlandforenvironmentalperformancereporting.AENValsomanagesthefinancialassuranceprogramthatencompassesmanytypesofdevelopmentincludingoilsands.TheERCBregulatesoilsandsminingandprocessingoperations,aswellasdiscardfromthoseoperations,includingtailings.AMemorandumofUnderstanding(MOU)betweenAENV,SRDandtheERCBoutlineseachagencysresponsibilitiesandhowtheyworktogether.TheMOUaddressestailingspondsandotheraspectsofmineableoilsandsmanagement,includingwateruseandreclamation. B.2.2AlbertaEnvironmentalProtectionandEnhancementActTheAlbertaEnvironmentalProtectionandEnhancementActprovidesthemandateforAENV.(Alberta,1993).ThewritersinterpretationofsomeunderlyingprinciplescontainedoftheAct,thathaveadirectbearingonoilsandsmanagement,include:

Thepartythatdisturbslandisresponsibleforrestoringit.ThedisturberisobligedtoqualifyforaReclamationCertificatethatsignifiesthelandhasbeensatisfactorilyreclaimed.Thepublicisinvitedtoreviewandinputtodecisionsontheenvironment.Regulatorsmayrequiredeveloperstoprovidefinancialassurancethatfundswillbeavailabletoreclaimsites.Theformandamountoffinancialassuranceisattheregulatorsdiscretion.Thereistobenointergenerationaltransferofenvironmentalliabilities.

B.2.3ERCBMandateTheERCBmandateisgovernedbyTheAlbertaOilSandsConservationAct.ApprovalsforminesandplantsarerequiredbySections10and11oftheAct.Approvaltocommence,suspend,orabandonanoilsandssiteisrequiredbySection3.ApprovalforstorageofdiscardgeneratedbyamineoraplantisrequiredbySections24and48.

B.2RegulatingOilSands

TheRockDoctorB.2RegulatingOilSands Page5

In2004theERCBandtheCanadianEnvironmentalAssessmentAgencyidentifiedseverallongtermobjectivesrespectingtailingsmanagement:

tominimizeandeventuallyeliminatelongtermstorageoffluidtailingsinthereclamationlandscape;tocreateatrafficablelandscapeattheearliestopportunitytofacilitateprogressivereclamation;toeliminateorreducecontainmentoffluidtailingsinanexternaltailingsdisposalareaduringoperations;toreducestoredprocessaffectedwastewatervolumesonsite;tomaximizeintermediateprocesswaterrecyclingtoincreaseenergyefficiencyandreducefreshwaterimport;tominimizeresourcesterilizationassociatedwithtailingsponds;andtoensurethattheliabilityfortailingsismanagedthroughreclamationoftailingsponds.

InFebruary2009theERCBissuedDirective074.Itrequiresoilsandoperatorstosolidifyincreasingamountsoffluidtailingseachyear,reportonfinesmanagement,andreportontheperformanceofeachtailingsfacilityannually.

B.3FiscalTermsforOilSands

TheRockDoctorB.3FiscalTermsforOilSandsPage5

B.3.FiscalTermsOilsandprojectsarehighlytaxedsothefiscalregimeisveryimportant.IndividualcomponentsofthefiscalregimeincludeAlbertaroyalty,capitalinvestmentincentives,andfederalandprovincialincometax.AlbertaRoyaltyvarieswiththestageofaprojectandthepriceofoil.Beforepayout,AlbertaRoyaltyisapercentageofGrossincome.Afterpayout,AlbertaRoyaltyisthegreaterof:aspecifiedpercentageofnetprofit,orapercentageofgrossincome.

Payoutoccurswhencumulativeincomeexceedscumulativeexpenditures.

Afterpayout,adollarofprofitissharedaccordingtofiscalterms,asgraphedonFigureB.3.Dependingonthepriceofoil,fiscalsharingleavesthedeveloperwith$0.45to$0.56fromeachdollarofprofit.Governmentsreceivetherest.Ifmoneyisspent,thesamefiscalsharingoccurs.Thenthecosttothedeveloperofspendingonedollaris$0.45to$0.56.Throughforegoneprofits,thegovernmentspaytherest.Fiscalsharingisanimportantpartofoilsandeconomicsandmustbepartofanyeconomicassessment.

0%

10%

20%

30%

40%

50%

60%

$40.00 $60.00 $80.00 $100.00 $120.00 $140.00 $160.00

Shareof

profit

and

expen

se%

PriceofOil$/bbl

FigureB.3Fiscalsharingvs priceofoil

AlbertaRoyalty

FederalIncomeTax

AlbertaIncomeTax

Developer

AllGovernmentCombined

B4Evolutionoftailingsandreclamationprocesses

The Rock DoctorB.4Evolutionoftailingsandreclamationpractices Page6

B.4Evolutionoftailingsandreclamationpractices

B.4.1EarlyHistory

Tailingspracticehasevolved.TherewerefewenvironmentalguidelineswhenSuncorstartedoperationsin1967.Thatwas5yearsbeforeAlbertaEnvironmentexisted.

TailingswereasurprisewhenSuncorstartedoperationsin1967.AtemporarydykewasconstructedtoTarIslandintheAthabascaRivertoholdthetailingsuntilasolutioncouldbefound.Todaythedykesofthatfacilityare100mhighanditisbeingreclaimedafter42yearsofservice.

Todayapplicationsforoilsandsdevelopmentareobligedtostudythelease,identifyallpotentialadverseimpactsandshowhowtheywillmanagethem.Theyarealsoobligedtosubmitalongtermclosureplan.Attheendoftheprojectoperatorsareexpectedtoreclaimthesiteandqualifyforareclamationcertificate.TheReclamationCertificateisissuedbythegovernmentandmeansthatreclaimedlandsareacceptabletotheregulatorsandthatthedeveloperisnolongerresponsible.

B.4.2The1990s

InitiallyallofSyncrudestailingswerestoredintheMildredLakefacility.

After10yearsofoperation,SyncrudeintroducedapumparoundsystemtopreventtheMildredLakefacilityfromfilling.(Listetal,1995).ItisillustratedbyFigureB.3.Thesystemworksasfollows:

PlantwasteispumpedtotheSouthWestSandStoragefacilitywheresandisdeposited.ThintailsrunoffispumpedtotheMildredLakeSettlingBasin.

AttheMildredLakefacility,finessettleandformMFT. MatureMFTispumpedfromtheMildredLakeSettlingBasintotheBaseMineLakestorage. MFTformakingCTisrecoveredfromtheMildredLakefacilityorfromtheBaseMineLake. CTisstoredintheactiveCTtailingsrepository.

InthesameperiodSuncordevelopednewfacilitiestoholdfluidtailingsinminedoutareas.FigureB.2showshowtailingspondsdominatetheSuncorbaseplantsite.



MLSB

SWSS

BML

EIP

Baseminelake

FigureB.4AerialViewSyncrudeMildredLakeSite

SiteBoundary

SuncorBoundary

MildredLakesettlingbasin

EastInPit

Southwestsandstorage 10km

.

InSyncrudes1992applicationforprojectexpansionSyncrudeproposedto:

DecreaseMFTproductionthroughanumberofinhouseinitiatives. SolidifyMFTusingtheCTprocess. PermanentlystoreMFTthatremainsattheendofoperationsbelowawatercapinanendpit

lake.TheyproposedafullscaledemonstrationtestintheBaseMineLakecommencingin2012.Thedemonstrationwouldlastfor10to15years.

TheERCBagreedtothedemonstrationtestprovidedthefacilitywouldbereclaimedifthetestwasnotsuccessful.TheERCBnotedthattheypreferredthatfluidtailingsbereclaimedasatrafficablesolid.TheyalsonotedthattheproposaltopermanentlystoreMFTunderawatercapwasnotapproved.(Houlihanetal,2008).

SinceSyncrudeproposeditin1992,mostoilsandapplicationshaveproposedtostartwithasurfacetailingspond,andthenswitchtoCTorequivalentwhentheprojectmovesinpit.Attheendoftheproject,fluidtailingsleftoverwouldbestoredpermanentlyunderawatercap.Thelistoflookalikeapplicationsinclude:

Syncrudeapplications(Syncrude1992,2002) Suncorapplications(ERCB2003,2004) Shelloilsandapplications(AlbianSands,2002,2003) KearlLakeapplication(Kearl,2005).



Syncrudesinhouseinitiativesprogramwasimplementedandwaslargelysuccessful.Themainprograminvolvedreducingthewatercontentintheextractionplantandinthetailingsdischargesofinescaptureinthesanddepositswouldbemaximized.FinesthatarecapturedinthebeacharenotavailabletomakeMFT.SyncrudesuccessfullyoperatedsmallscaledemonstrationtestswithwateroverMFT.However,thetestsweresmallanddidnotevaluatetheeffectofgasemissionsthatstartedatalaterdate.SyncrudeevaluatedCTina5millioncubicmetredemonstrationpilotinthemid1990s.TheystartedusingCTincommercialoperationsin1999.ThatdepositisbeingpreparedforreclamationthefirsttailingspondtobereclaimedatSyncrude.(Fair,2008).

SuncorhavebeenusingCTincommercialoperationssincethe1995.(Shaw,2008).Suncorarereclaimingtheirstartuppondthathadbeeninuseforover40years.

B.4.3RecenteventsIndustryappearstofocuson:

Traditionalplantstomakefluidtailingsuntiloperationscanmoveinpit; ThensolidifyfluidtailingsusingCToranequivalenttechnology; Permanentlystoreresidualamountsoffluidtailingsunderawatercappedendpitlake.

ThatisastrongcontrasttothegoalssetoutbytheERCB(Houlihanet.Al.2008):

Minimizeandeventuallyeliminatelongtermstorageoffluidtailings.Createatrafficablelandscapeattheearliestopportunity. Eliminateorreducefluidtailingsinanexternaltailingsdisposalarea. Ensurethattheliabilityfortailingsismanagedthroughreclamation.Pilotresearchisapparentlyevaluatingothertechnologiessuchassandstacking,thickenerevaluations,cyclonetreatment,drying,freezethawtreatmentandcentrifugetreatment.(Fair,2008).Suncoraremanyoftheaboveaswellasselfcontainedmobilemine/extractionunits.GeneralinformationabouttheSyncrudeorSuncorresearchhasbeenreleasedbutlittleifanyspecificshavebeenmadepublic.Shellareresearchingthickenedtailingsoptions(Matthews,(2008)).Theystartedtheiroperationwithouttheuseofdispersingagentstoreducetailingsproduced.However,theyhavesubsequentlybeenaddingsodiumcitrate,adispersant.Shellarestillproducingthickenedtailingsandstoringitintheiroutofpitstarterpond.InthepastdecadeSyncrudeproducedabout200millioncubicmetresofMFT.TenpercentofthatwassolidifiedwithCTtreatment.(Fair,2008).



MFTstorageinterfereswithlandreclamation.Syncrudehavedisturbedovertwotownshipsoflandarea.20%hasbeenreclaimed.Suncorhaveonlyreclaimed4%oftheirdisturbedlands.Todate104hectaresintheoilsandregionhavereceivedformalreclamationcertificates.TheTotalapplication(Total,2006a,2006b)proposetostoreweakCTatdepth,coveritwithstrongerCTallofwhichwillbecoveredwithastrongsandcap.(Total2006b).FigureB.5illustratestheTotalproposal.

HighFinesCT Weakdeposit

Dyke Dyke

Strongcap

Workingsurface

LowfinesCT

Reclaimedsurface

FigureB.6Proposaltocapweaktailings

FigureB.6showsthegrowthofMFTforthewholeindustry.Todaythevolumetotals750millioncubicmetres.IfthereisnochangeinprocessesusedthevolumeisforecasttoreachIbillioncubicmetresin2014andtwobillionin2034.(Houlihanet.al.2008).

Figure B.6 Regional MFT Inventory to date



B.4.4500Ducks OilsandsdevelopmentsarelocatedonamajorflywaythatbirdsuseastheymigratetonestingsitesintheArctic.Millionsofbirdsflyovertheoilsandsdevelopmentseachspring,andreturnwiththeiryoungeachfall.Tailingspondsareincompatiblewiththisnaturalmigrationbecausebirdsthatlandonthepondsareapttobecomeoilcoveredanddie.FigureB.7showsoilonthesurfaceofaSyncrudetailingspond.

FigureB.7Oilonthesurfaceofatailingspond

Deterrentssuchasmansizedstatuesstandingonfloatsspacedatregularintervalsonthepondsurfaceareusedtokeepthebirdsfromlanding.Thestatuesaresupplementedbypropane"cannons"thatfireatregularintervalsandmimicshotgunblasts.AlbianSandsusearadarscannertodetectincomingbirdsandactivateanartificialhawktoscarebirdsaway.InApril2008,latewinterstormsdelayedinstallationoftheseasonalduckdeterrents.AflockofMallardduckslandedonaSyncrudetailingspondbeforethedeterrentswereinstalled.500+ducksperished.

Adverseworldwidepublicityfollowed.Internetsearchesrevealaplethoraofantioilsand,antiCanada,andantiU.S.A.websites,books(Nikiforuk,2008),andmagazines(Kuneig,R.,(2009),NationalGeographic).Thepublicitymayexaggerateandsupportotheragendasonenergyuseandclimatechange.However,someoftheconcernsarejustifiedandrevealanoilsandindustryoutlookthat,ifSyncrude's2006C&RPlanisamodel(Syncrude,2006),wassadlyoutofdate.Theimpactisdamagingthemarketabilityofoilsandsproducts,andCanada'simageinworldtrade.



B.4.5ERCBDirective074In2008theERCBheldmeetingswithoilsandoperatorstoshareconcernsaboutthegrowinginventoryoffluidtailingsandtodiscussnewreportingrequirements.InFebruary,2009theERCBissuedDirective074.Itrequiresoperatorstoreportonallfinesprocessedandtosolidifyincreasingpercentagesofthefinesprocessedeachyear.(20%,30%,and50%inthenextthreeyears).TheDirectivespecifiesstrengthcriteriaforthesolidifiedfines(aminimumundrainedshearstrengthof5kPainthefirstyearandaminimumof10RPaafter5years).Inaddition.Directive074requiresthatoperatorsinventorytheirtailingspondsandreportperformanceannually.HoulihanpresentedasummaryofthepublicandregulatoryconcernsabouttailingsthatwerebehindDirective074(Houlihanetal,2008).Publicconcerns:

Seepageandpotentialwatercontamination,Fugitiveemissions,Riskofatailingsdamfailure,Returnofthelandtotraditionaluse,Progressivereclamation(lackofit),Intergenerationaltransferofliability.

Regulator'sconcerns:Applicationsunderestimatethefluidtailingsvolumes,CTperformancetargetsandcommitmentsnotmet,Fluidvolumesgrowingsteadily,Nofluidtailingspondreclaimed,Neitherthepublicnorthegovernmentispreparedtoacceptcommitmentsthatarenotmetandincreasingliabilities.

Historicallythegovernmenthasencouragedindustrytoshowleadershipinoilsandsmanagement.Directive074representsanewdirection.

B.5OilSandGeology

The Rock DoctorB.5OilSandGeologyPage12

B.5OilSandGeology B.5.1ResourceBasemineablearea

TheERCBestimatesthat35billionbarrelsofbitumenisrecoverablefromthesurfacemineablearea(ERCB,(2009b)).

Formineabledevelopmentstheminimumresourcebaseisenoughtosupportaprojectfor25years.Thatamountstoover1billionbarrelsofreservesper100,000barrelsofproductionperday..

B.5.2BedrockGeology

Themineableoilsandareaisdefinedasoilsandthathasupto50metresofoverburdenovertheorezone.ItislocatednorthofFortMcMurray.FigureB.8showsthedistributionofbedrockformationsintheFortMcMurrayarea.(Alberta,2009)GraniteoftheCanadianShieldliesundertheoilsandareaafewhundredmetresbelowsurface.ThegraniteiscoveredbyPaleozoicformationsofsandstone,salt,shale,limestoneanddolomitethatdipgentlytothewest.TheMcMurrayFormationisthehostrockforbitumen.ItwasdepositedunconformablyontopofthePaleozoicformations.ItisofCretaceousage,(120millionyearsold).Depositionalenvironments,createdwhenashallowseainvadedthearea,leftcomplexlyinterlayereddepositsofsand,siltandclay.TheClearwaterformationwasdepositedontopoftheMcMurray.Itcontainsmarinedepositsthatformedinthedeepenedsea.SomelayersoftheClearwateraresandybutmostareclayshalethatcontainsconsiderableamountsofbentonite.OtherformationsfollowedsoatonetimetheMcMurraywascoveredbyonetotwokilometresofsediment.

B.5.3Localstructure

SolutionofthesaltbedswasoccurringinduringCretaceoustime,especiallyeastoftheAthabascaRiver.Solutionactivitydisruptsthecontinuityofoverlyingbeds.ThickenedsectionsoftheMcMurraydevelopedinareasthatweresubsidinginCretaceoustime.Karstfeatures,evidentonsurfacetoday,indicatethatsolutionactivityiscontinuing.(Fraser,1975).

B.5OilSandGeology


FigureB.8 BedrockoftheMineableOilSandsArea

B.5OilSandGeology


TheBitumontbasindevelopednorthofSuncorandSyncrude.ItisindicatedonFigureB.8bythecircularareaoccupiedbyClearwaterclay/shale.Theretheentireprofile,includingthegranitesurfacesubsided,indicatingthattheoriginismoredeepseatedthansolutionofsaltbeds.SubsidenceduringMcMurraytimeresultedinthickerandcoarserbedsofsand.Subsidenceafteroilenteredtheareadepressedpartsofthebitumensaturatedzone30metresbelowtheAthabascaRiver.(Isherwood,2009).

B.5.4OriginofthebitumenAtanunknowntime,conventionaloilfromtheAlbertaBasinmigratedeastwardintothearea.Itfloatedonawaterlayer,andfilledthetopoftheMcMurrayformation.Bacterialactionstrippedlightcomponentsfromtheoil,leavingheavybitumen.(McNeely,1973).Thebitumen/waterinterfacetendstobehorizontalintheSuncorarea,coincidingwiththepresentleveloftheAthabascaRiver.IntheBitumontBasinthebitumensaturatedzoneisdepressedabout30metresbelowtheAthabascaRiver.

B.5.5SurficialGeologySurficialdepositsincludePleistoceneglacialtillbothdensebasaltillandweakerablationtill.Outwashdeposits,windblownsandsandlacustrinedepositsfollowedatthecloseofthePleistoceneglaciation.Surfacedepositsincludelocalalluviumandmuskegdeposits.Continentalglaciationsmeltedfromsouthtonorth.Thenorthernsectionsblockeddrainagesolargelakesformedsouthoftheicesheet.GlacialLakeAgassizcoveredmuchofManitobaandSaskatchewan.About10,000yearsagoitdischargeddowntheClearwaterRiverandcarvedthepresentvalleyoftheAthabascaRivernorthofFortMcMurray.(Smithet.al.,1993).UpstreamfromFortMcMurraytheAthabascaRiverflowsonbedrock.DownstreamfromFortMcMurraythereisaburiedvalleybelowtheAthabascaRiver.TheburiedvalleyNorthofNorthofFortMcMurrayprobablyrepresentsapreCretaceousrivervalley(Devenny,2000).ContinuingsaltsolutionisindicatedbysaltspringsthatentertheAthabascaRiverespeciallyneartheBitumontBasin(Bauman,2008).UpstreamfromFortMcMurraytheAthabascaRiverflowsonthesurfaceofPaleozoicbedrock.DownstreamfromFortMcMurraythereisaburiedvalleybelowtheAthabascaRiver.TheburiedvalleyNorthofNorthofFortMcMurrayprobablyrepresentsapreCretaceousrivervalley(Devenny,2000).ContinuingsaltsolutionisindicatedbynaturalsaltspringsthatentertheAthabascaRiverespeciallyneartheBitumontBasin.(Bauman,2008).

B.2.6Orebodycharacter

B.5OilSandGeology


Inthemineableoilsandsarea,overburdentendstobeabout50metresthick.Theorezonealsotendstobeabout50metresthick.Oregradesarehighestinsandyzones(ashighas15%byweightbitumen)andlowestwherefinegrainedmaterialispresent.Table3.characterizesaverageoreatSyncrude.TableB.3AverageoreusedinthestudyreportedinReportA

Component Weight% Weightpercubicmetre(tonnes)

Volumeinonecubicmetre

Density/specificgravity

Bitumen 11% 0.231 0.229 1.01Water 5% 0.105 0.105 1.00Fines 16% 0.336 0.127 2.65Sand 68% 1.428 0.539 2.65Total 100% 2.100 1.000

ThefollowingdiscussiondealswithfactsaboutaverageorethatwecaninterpretfromTableB.3.

1. TheBitumendensityisveryclosetothedensityofwater.Thatchallengesseparationinextractionandisthereasonthatairbubbleassistanceisusedtofloatbitumen.Itisalsothereasonthatsolventisusedtochangethedensityofbitumeninfrothtreatment.

2. Bitumenrepresents22%ofthetotalvolumeofoilsandore.Thatsuggestsacleanporoussand.3. Theclay/waterratioislowindicatingthatinsitutheclayisnotdispersed.

Otherfactsaboutoilsandore:

4. Oilsandoreishighlyvariable,aresultofthevariabledepositionalenvironmentsofthehostreservoir.Itcontainscomplexlyinterlayeredoreandwastedepositsofsand,silt,andclay.Allprocesses,fromtheminefacethroughextractionandtailings,mustberobustandabletoaccommodatevariationsintheore.

5. Quartzandclaymineralsilmeniteandkaolinarethedominantmineralsinoilsand.6. Aquartzsurfacehasagreateraffinityforwaterthanbitumen.Asaresulteachsandgrainis

surroundedbyathinfilmofwaterthatallowseasyseparationviaagitationinhotwater.Oilsanddepositselsewhereintheworldareoftencomposedofothermineralsthatattractbitumentothesandgrainsurface.Theyrequiresolventtoextractthebitumen.

7. Bitumenparticlesreleasedinextractionreflectthesizeofthevoidspacethattheyarereleasedfrom.Insandthevoidspaceisquitelarge.Infinegrainedsoilthevoidspaceisquitefine.

8. Bitumenassociatedwithfinegraineddepositscanbedifficulttoextractbecause: Thesurfacemaybeoilwet, Bitumendropletsaretoofineforairbubblestocontactandfloatthemtosurface.

9. Thereareminorquantitiesofheavymineralsilmenite,rutileandzircon.Centrifugeactioninextractionconcentratestheheavymineralsmanyfoldsotheyarepotentialoresfortitaniumandzirconium.

10. Bitumencontainscoproductssulphur,cokeandvanadium.

B.6MiningOilSand

The Rock DoctorB.6MiningOilSandPage16

B.6MiningAllprojectsmineoverburdenandoreusinglargeshovelsand400tontrucks.Oreishauledtoadumpfacilitywhereitiscrushed,screened,slurriedwithwarmprocesswaterandpumpedtotheextractionplant.Turbulenceduringhydrotransport,breakstheoreintoindividualparticlesneededforseparationinextraction.Processaids,dispersingagentsandsmallairbubbles,areaddedbeforetheorereachesextraction.Minewaste(overburdenandinterburden)ishauledtowastedumps.Suitablewasteisalsousedtoconstructfacilitiessuchastailingsdykes.Itisusuallycompactedbydriving400tontrucksoverit.Somewastesareunsuitableforconstruction,becausetheyaretoowet,orcontainundesirablematerial(e.g.swellinganderodibleclaysoftheClearwaterFormation.)Careisrequiredtoensurethatmaterialsthataredeleterioustoextractionarekeptoutoftheoresupply.DeleteriousmaterialsincludeactiveclayfromtheClearwaterFormation.FigureB.8showsa400tontruckthatisusedinoilsandmining.FigureB.9showsashovelloadingoreontoa400tontruck.Shovelsaresizedsotheycanfillthetruckswiththreescoops.

FigureB.9400tonminetruck

ERCBInterimDirectiveID20017stipulatescutoffcriteriaformining.ProjectsareexpectedtominetoaminimumTV/BIPof12whereTVisthetotalvolumeofore,interburdenandoverburden,andBIPisthevolumeofbitumeninplace.Theminimumwastelayeris3metresthick.Thecutoffgradeis7%.

B.6MiningOilSand


Mineopeningsmustdepressurizeaquifersencounteredinandbelowtheorebody.AttheSuncorandSyncrudebaseplantsgroundwateraquifersarelimitedandtheoreseldomdipsbelowtheleveloftheAthabascaRiver.AtAlbianSandsthebasalaquiferismoreextensivebutminingactivitytendstobeabovetheleveloftheAthabascaRiver.ProjectsinandneartheBitumontBasincouldbeminingore30metresbelowthesurfaceoftheAthabascaRiver.Groundwatercontrolinthoseminescouldencounterlargequantitiesofverysalinewater.

FigureB.10Loadinga400tonhaultruck

Minedoutareasarebackfilledwithoverburdenandtailings.FigureB.11showshowtailingsandminingactivityexistsidebysideatSyncrude.Itcantake50yearstoaccommodatemining,tailingsstorage,tailingsreclamationandfinallysurfacereclamation.Therearewasteproductsthatmustbeaccommodatedinminedoutareas:

Overburdenandinterburdenwaste, MaterialrejectedatthescreenbeforeHydrotransport(cementedlayersandclaylumps), Cokeproducedinupgrading(approximately2milliontonnesperyearatbothSyncrudeand

Suncor).TheERCBrequiresthatcokebeplacedsoitwillbeaccessibletofuturegenerations.

Sulphur(usuallystoredonsitebecauseshippingcostexceedsthemarketvalue).Sulphurisalsostoredsoitwillbeaccessibleinthefuture.

B.6MiningOilSand


FigureB.11HowminingandtailingsworkinpitatSyncrude

Legend

EIP EastinPitMineSWIP SouthWestinPitmineNorthMineActiveNorthMine

B.7Extraction

The Rock DoctorB.7ExtractionPage19

B.7Extraction

FigureB.11showsasimplifiedprocessflowsheetforanoilsandextractionplant.

MiddlingsTreatment

FigureB.5SimpleExtractionProcessFlowSheet

Mixer

MineSlurry CrushScreenHydrotransport

FrothCleaningPSVDesander

FloodWater

ToTailingsToTailings

Froth

Thefirststepinextractionistoaddwatertotheincomingoreslurry.Thefirstvesselintheextractionplantcontainsrelativelystillwater.Inthatenvironmentsanddropsoutofsuspensionandissenttotailings.Bitumen,aidedbysmallattachedairbubblesfloatstothesurfacewhereitisremovedasfroth.Theremainingmixtureiscalledmiddlings.Itcontainswater,silt,clay,andsmalldropletsofbitumen,issenttothenextstageoftheextractionplantforfurtherprocessing.Afterbitumenhasbeenremovedfromthemiddlingscircuitresidualwasteisblendedwiththesandtailingsstreamandsenttotailings.Infrothtreatment,solventisaddedtodilutebitumenandtochangeitsspecificgravity.Thentheslurryiscentrifugedtoseparatethebitumenfromwaterandsolids.Residualwastecontainingwater,solids,unrecoveredbitumenandsolventlossesisdischargedasfrothtreatmenttailings.

B.7Extraction


Frothtreatmenttailingscontainthemostbitumenandsolventaswellasconcentrationsofheavymineralssuchasilmenite,rutileandmonazite.Thereissomeinterestinilmeniteandrutileaspotentialsourcesoftitanium.Monazitecontainsradioactiveelementsthataredetectablewithgeophysicalloggingtools.Blendingfrothtreatmenttailingswithregulartailingsdegradesthequalityofregulartailings.Italsowastesconcentratedilmeniteandrutile,andaddsconcentrationsofradioactivitythatinterferewithusinggeophysicaltoolstodeterminetheclaycontentofMFT.Perhapswastefromfrothtreatmentshouldbestoredseparately.

Theextractionsystemsdescribedareillustrative.Otherconfigurationsarealsoused.

ERCBInterimDirectiveID20017specifiestheminimumbitumenrecovery.Fororethatcontainsmorethan11%byweightbitumen,extractionisexpectedtorecover90%ormoreofthebitumen.Fororegradesbetween7%and11%theminimumbitumenrecoverycurveisindicatedbyFigureB.13.

30%

40%

50%

60%

70%

80%

90%

100%

6% 7% 8% 9% 10% 11% 12% 13% 14%

Minim

umRecovery%

OreGrade%

Figure6ERCBBitumenExtractionRecoveryCurve

ERCBRecoveryCriteria

Maximumore/rejectthickness3mCutoffgrade

7%TV/BIP Cutoff 12

Minimumrecoveryinextraction(Recovery=54.1X 2.5X2 202.7)whereX=feedgrade

SuncorandSyncrudeoperateintegratedplants.Theyproducebitumenthatissuitablefortheironsiteupgraderbutdoesnotmeetspecificationsforpipelinetransport.Table1indicatesthatSuncorandSyncruderecover92%and90.7%ofthebitumeninextraction.ThedifferenceprobablyreflectsslightlylowergradeoreatSyncrude.

B.7Extraction


TheAlbianSandsProjectproducesbitumenandthenshipsit455kmtotheShellupgraderinScotfordAlberta.PipelinespecificationsrequirecleanerbitumenthanSyncrudeandSuncorproduce.Thenewfrothtreatmentusedtoproducecleanbitumencausesasphaltenestoprecipitate.Theyareaddedtotailingsfromfrothtreatment.AsaresulttheoverallhydrocarbonrecoveryatAlbianSandsisprobably80%orless.

SuncorandSyncrudeaddcausticsodainextractiontofacilitatebitumenremoval.Causticsodaalsodispersesclay.Thataddstothevolumeoffluidtailingscreated.

Originally,AlbianSandsproposedtooperateextractionwithoutaddingdispersingagents.Thereason:anticipatedsuperiorperformanceintailingsdenser,rapidlysettlingtailings,andfasterwaterclarification.However,theprojectnowaddssodiumcitrate,adispersingagent,toaidbitumenextraction.

Processwaterdischargedinthewastestreamsfromextractioncontainsheat.Heatlossisreducediftheamountofwaterdischargedwithplantwasteisreduced.

Waterdischargecanbereducedbyconcentratingthesolidcontentofthedischargestreams.Thefinesstreamcanbeconcentratedtoabout30%solidsinathickener.Thesandwastestreamcanbedensifiedbycyclonestoover70%solids.Processwaterrecoveredintheplant,withitscontainedheat,isimmediatelyrecycledandreused.

Traditionalextractionproduceswastethatcanbepumped.Theupperlimitforthestrengthofpumpablewasteis100kPa.Thatis1%ofthestrengthdesiredforreclamation.

B.8BasicTailingsfromExtractiontoMFT

TheRockDoctorB.8BasicTailingsfromExtractiontoMFTPage22

B.8BasicTailingsfromextractiontoMFT

B.8.1IntroductiontoTailings

Tailingsarethewasteproductofoilsandprocessing.

Theassignmentfortailingsmanagementis:

1. Receiveallsolidandfluidwasteproducedbyextraction,2. Storeitinasafe,costeffectivemanner,3. Returnclarifiedprocesswatertotheplantforreuse,4. Reclaimwastedepositstomeetreclamationrequirementsforclosureinatimelymanner.

Theassignmentisadifficultonebecause:

Tailingswasteisreceivedasaliquidslurry. Azerodischargepolicyrequiresthatallprocessaffectedwaterberetainedonsite. Forclosure,someofthewastemustbetransformedintoastrong,selfsupportingsolid. Extractiondonotknowtheclaycontentoftheirtailingsdischarge.

B.8.2Thetailingscycle

FigureB.14showsthestepsinthepaththattransformsoretotailings.FigureB.15showstherelativevolumeofthecomponentsoftailingsalongthatpath.Stepsintailingsmanagementaredescribedbelow:

Oreismined,slurriedandpumpedtoextraction.Intransittheoreseparatesintoindividualparticles,inpreparationforbitumenextraction.Thevolumeofsolidsremainconstantfromstagetostage.Volumechangesareduetobitumenremoval,wateradditionandwaterremoval.

Inextractiontheorecomponentsareseparatedintothreestreams(coarse,finesandfroth)becauseeachrequiresdifferenttreatment.Afterbitumenhasbeenextracted,thesandandfineswastestreamsarecombinedandpumpedtothetailingsdisposalsite.Frothtreatmentwastemaybepumpeddirectlytothetailingspond.Wasteslurriessenttotailingscontainprocesswater,sand,fines,unrecoveredbitumen,andminorimpuritiesfromnaturalandmanmadesources.Whentailingsexittheplantthevolumeoftheslurryismorethantwicetheoriginalvolumeoftheore.Heatlossisassociatedwiththelargevolumeofwaterinthetailingsslurry.



MFT

NativeSoil

SolidFineTails

WaterClarificationZone

BeachSand

SandDyke Beach

Sand

SandDyke

ProductOre

BitumenWaterFinesSand

WaterfromSFT

MakeupWater

Hydrotransport

OverflowToPond

ExtractionPlant

RecycleWater

7

6

54

3

2

1FigureB.14TheOilSandsTailingsCycle

0

0.5

1

1.5

2

2.5

3

ChartTitle

Bitumen

Water

Fines

Sand

FigureB.15Volumechangeonthepathfromoretowaste



Atthewastestoragesite,theslurryisdischargedontoasanddeposit.Seventyfivepercentofthewasteaccumulatesasasolidsanddeposit.Voidspaceinthesandisfilledwithwaterandsuspendedcomponents.Thevoidspaceinthesandisalmostequaltothevolumeoffluidtailings.Surplusmaterialoverflowstothepond.

Materialenteringthetailingspondconsistsofadilutesuspensionofwater,fines,unrecoveredbitumenandsolvent,andimpurities.SectionB.A4.3inAppendixB.4describeshowsolidssettletobecomeMFT.

MosttailingsmaterialbalancesinApplicationsforacommercialdevelopmentstopattheMFTstage.FiguresB.14andB.15assumethatclosurerequiresthatMFTshouldbereclaimedassolidfinetailingsorSFT.ThefinalstepchangesMFTtoSFTwithafinesdensityof70%solidsbyweight.

Surpluswaterinthepondisavailableforreuse.WhenthefinesarestoredasMFTthevolumeavailableforrecycleis1.15cubicmetrespercubicmetreofaverageoreprocessed.ConvertingMFTtoSFTaddsanadditional0.18cubicmetresofwatertorecycle.

Dissolvedsaltsaccumulatewitheachtimewaterisreused.Thesaltscomefromconnatewaterintheore,minedepressurizationwater,andprocessaids.

Lord(Lordetal,1997).reportsMFTdensitiesof35%andeven40%atSyncrude.Thedensitiesnotedindicatethatsomeconsolidationistakingplace.TherearesubtledifferencesinMFTatSyncrudeandSuncor(McKinnonetal,1993).Theprecedingfactsdonotchangethethrustofdiscussionsinthisreport.

Tailingswaterbecomessaltierwithreuse.Implications:

Atsomepointthewaterchemistrywillcauseclaytoflocculateinextractionhaltingbitumenextraction.

Saltyprocesswatersuppressesvegetationsoadverselyaffectsreclamation. Itwillbedifficulttoassimilatetailingswaterinthesurroundingsifitistoosalty.

B.8.3Transportingtailings

Processwasteisblendedandpumpedtothetailingsdisposalsiteforseveralreasons:

Finegrainedcomponentsassistfluidtransportofsand. Blendedwastemeansthatonlyonetransportsystemisneeded. Wasteispumpedbecauseitisbelievedtobethelowestcosttransportsystem. Dischargedwasteautomaticallyflowstoitsfinalrestingplace.



Tailingsispumpedataspeedof3to5metrespersecondtokeepallsolidsinsuspension.

Theupperlimitonstrengthforpumpedslurriesisabout100kPa.Thestrengthofthepumpedmaterialwillhavetoincreasebyafactorof100toequal10kPa,thelowerlimitofstrengthdesiredforsolidreclaimabletailings.

Tosaveheat,operatorstrytokeepthedensityofthewasteslurryhigh(between50%and60%solids).Itisnotpracticaltopumpathigherdensities.

B.8.4TailingsSanddeposits

Threetypesofsanddepositsformattheendofthetailingsline.

Sandconstructioncell

Largecellsarecreatedtocollectsandforconstruction.Whenthetailingsslurryentersthebroadcell,flowvelocitydecreasesandsanddropsoutofsuspension.Dozersmaintainsmallperimeterdykesaroundthecellandcompactthenewlydepositedsandbytrackingbackandforthacrossit.Voidspaceinthesandisfilledwithprocesswaterandsuspendedmaterial.

FigureB.16isaphotoofatailingssandcellinpreparation.FigureB.17isaphotoofadozercompactingsandintheconstructioncell.(Matthews,2008).

FigureB.16PreparationofaconstructioncellatAlbianSands



FigureB.17Dozercompactingsandinaconstructioncell

Sandthatisnotusedforconstructionisdirectedtothebeach.

BeachdepositsareindicatedonFigureA.17.

FigureB.18DepositingConventionalTailings

ExtractionSand

Fines

Water

Recyclewater

MFT

Beach Beachabovewater

Beachbelowwater

Pond

MFT

Clearwater

Transition



Beachabovewater

Thetailingsdischargeisspreadoverthebeachtopreventconcentratedflow.Smallstreamsflowoverthebeach.Theydeposit,erodeandredepositsandandmaterialcapturedinthevoids.Thatmakesthedepositinthebeachabovewaterhighlyvariable,rangingfromcleansandtosandwithvoidsfilledwithcapturedmaterial.

Beachbelowwater

Conditionsinthebeachbelowwaterarequieterthantheyareabovewater.

Intheunderwaterenvironmentgentleplacementcreatesloosedepositsformthatcantrapalotoffinegrainedmaterial.Theloosedepositsarepronetoliquefaction.SubmarinelandslidesandturbidityflowsarepartofthesystemthatdeliversmaterialdowntheslopeandintoadjacentdepositsofMFT.

ThevolumeandcharacterofsanddepositsisrelativelypredictableandissummarizedbyTableB.4.Thevolumeandcharacterofthefinetailingscomponentismuchmorecomplicated,partlybecauseinformationonclayanditsactivityisnotcollected.TableB.4Forecastpropertiesoftailingssanddeposits:

Deposit PorosityN

VoidRatioe

Weight%Solids%

DryDensityt/m3

BeachSlope%

Sandcompactedinacell 0.37 0.6 82% 1.67 Sanddepositedinabeachabovewater 0.40 0.68 80% 1.59 2%Sanddepositedinabeachbelowwater 0.43 0.75 78% 1.51 4%FinesformingMFTinthepond 0.86 6.2 30% 0.37

B.8.5Behaviourinthetailingspond

Thetailingspondisalargevesselthatclarifieswaterandprovidesstorageforfinegraineddeposits.

Materialthatentersthetailingspondconsistsofwater,unrecoveredbitumen,silt,clay,dissolvedchemicals,solventlosses,andprocessaids.

Thewasteslurryenteringthetailingspondisquitedilute,withatypicalsolidcontentof5to10%.Suspendedsolidsslowlysettleleavingclearwaterbehind.Asthesolidssettle,thesuspensionbecomesdenserandparticlesinterferewitheachother.Thistransitionzoneextendstoadepthofafewmetres.Finally,whenthedensityreachesabout30%solids,repulsiveforcesbetweenclayparticlespreventfurtherdensification.ThedepositatthatstageisknownasmaturefinetailsorMFT.



AweaksoilstructureformsinMFTandrepresentsthestartofsoilstrength.Initiallythedepositisextremelyweak.ThelowstrengthinearlyMFTisindicatedbythefactthatindividualsandgrainsbreakthroughitandaccumulateatthebaseofthedeposit10sofmetresbelow.

Whensurfacewaterreachesasolidcontentof0.1%itcanberecycledtotheplant.(FineTailsFundamentalsConsortium(1995)pageIV74.)

Matsofbitumenalsoaccumulateintheponddeposits.

B.8.6Predictingthevolumeoftailings

Tailingspersonnelareresponsibleforforecastingthevolumeoftailingssostoragefacilitiescanbeconstructedandreadytostoreexpectedtailings.

Thevolumesofsanddepositsarepredictable,butthevolumeoffinetailingsisnot.ThevolumeofMFTisalargelyaresultofclay,andthewayitinteractswithwaterandthechemicalspresentinthewater.Extractionoperatorsdonotmeasuretheclaycontent.Theymeasurefinesthatcancontainfrom0%to100%claysizedmaterial.

Theaccuracyoftailingsforecastmodels,thatdonotconsidertheamountofclaypresent,ortheextentofclaydispersion,ishighlysuspect.OtherindicatorsoftheMFTvolumecanbederivedfromhistoricaldata.AtSyncrudetheaveragevolumeofMFTproducedpercubicmetreofaverageoreis0.266cubicmetres.

Atailingsforecastmodelwasdevelopedtoexploretrendsaffectingtailingsvolumes.FindingsaresummarizedinTableB.5below.AnelectroniccopyofthetailingsforecastmodelisinAppendixB.1.

TableB.5Highlightsofinformationobtainedfromthetailingsforecastmodel:

1. Oilsandextractioncreatestwotypesofwastedeposits:sanddepositsthataresolid,andfluidtailingsdepositsthatmustbecontained.Wastederivedfromaverageoreis75%sandand25%fluidtailings(MFT).

2. Foraverageorethevoidspaceinthesandisalmostequaltothevolumeoffluidtailings.3. Finescaptureinthevoidspaceofsandisimportant:

a. Finescapturedinthesanddisplacewaterandtherebyreducewaterloss.b. FinescapturedinthesandarenotavailabletomakeMFTinthepond.

4. Lowgrade(highfines)oreyieldslessbitumen,createsconsiderablymoreMFT,consumesmorewater,andresultsinhigherheatlossthanhighgradeore.

5. MethodsofreducingtheamountofMFTinclude:a. Reduceclaydispersionintheextractionprocess.



b. Increasethedensityofthewasteslurrydischargedfromtheplant.c. IncreasethedensityofMFT.

6. Heatlossisproportionaltotheamountofhotwaterdischargedfromtheplant.Itcanbereducedbydensifyingthewastedischargestream(captureandrecycleprocesswaterwiththecontainedheat).

7. WaterlossequalstheamountofwatertrappedinsandvoidsandinMFT.Watersurplustothoseneedsisavailableforrecycletotheplant.Waterlosscanbereducedbydensifyingthedischargestream(notedin6above)andbyreducingthecreationofMFT(Item5above).

8. Themodelforecaststhatmostoftheunrecoveredbitumenwillconcentrateinthepond.Bitumenfollowswatertothepond,andthewateristhenrecycled.

9. IfMFTisdensifiedtoasolidstate,the%bitumenbyweightcouldriseto11%andthevolumeto17%.Iftailingsalsoincludesasphaltenes,theabovenumberscoulddouble.ThatsuggeststhatseriousconsiderationshouldbegiventorecoveringbitumenifMFTisreprocessed.

B.9TailingsDams

The Rock DoctorB.9TailingsDamsPage30

B.9TailingsDams

B.9.1Introductiontotailingsdams

Buildingcontainmentstructurestoholdfluidwasteisanimportantpartoftailingsmanagement.

Tailingsdykesaremassivestructures.TypicaldimensionsofthetailingsfacilitiesareshowninTableB.6

TableB.6Typicaldimensionsoftailingsdykes.

Height 50to100metresCrestwidth 50+metresSideslope 1:4withgoodfoundations

1:15overpoorfoundationssuchastheClearwaterFormationFootprint 1,500hectaresandabove

Thedykesprovidespacetostoresand,sodimensionscanbequitegenerous.Atthestartofaprojectwasteisplacedonsurfaceuntilthereisroomtoplaceitinpit.TableB.7showshighlightsofthesurfacepondproposedintheShellJackpineapplication(AlbianSands,2003).TableB.7HighightsoftheJackpinesurfacetailingspond.

Designlifeofactivephase 6yearsFootprint 1,600hectaresDykeheight 50mHoldingcapacity Fluidtailings 278millionm3 Beachedsand 171millionm3 Compacteddykes 115millionm3 Total 565millionm3

Dykesareoftenconstructedofsandusingtheconstructioncellsdescribedearlier.Sandaccumulatesintheconstructioncellandiscompactedbydozers.Finegrainedmaterialremainsinsuspensionandflowstothetailingspond.

FigureB.19showsatailingsdykeconstructedusingthecentrelinemethod.FigureB.20showstheupstreammethodofdykeconstruction.

B.9TailingsDams


Centrelineofdyke

EngineeredFill

Upstream Downstream

MFT

BeachedFillWaterCap

Nativesoilfoundation

FigureB.19.CrosssectionofatailingsdykeCentreline constructionmethod

Starterdyke

EngineeredFill

BeachedFillWaterCap

MFT

Nativegroundfoundation

StableBeachFoundation

UncertainBeachFoundation

FigureB.20CrosssectionofatailingsdykeUpstreamconstructionmethod

StarterDyke

Withcentrelineconstructionallmaterialdownstreamofthecentrelineisaccumulatedinconstructioncellsandcompacted.Materialplacedonthepondsideofthecentrelineispumpedontoabeach,butisnotcompacted.Materialthatisnotusedincellconstructionisdischargedontobeaches.

Withupstreamconstructiontheexternalfaceofthedykeisconstructedofcompactedcellsand.Sandplacedonthepondsideisbeachedbutnotcompacted.Asthedykegrowshigherthecompactedfaceshiftsupstream.Eventuallythatplacesitaboveuncompactedbeachsands.Theadvantageoftheupstreammethodisalowercostandapermanentexternalfacethatisreadytobereclaimed.Thedisadvantageisapotentiallypoorfoundation.Thereisariskthatsanddepositedunderwaterwill

B.9TailingsDams


experienceliquefaction.Inaddition,thepoorfoundationmaypreventraisingthedykeabovethedesignlevelinthefuture.Dykeraisingiscommonwithoilsandtailingsponds.

B.9.2Constructingwithoverburdeninsteadofsand Sometimesoverburdenorminewaste,insteadofsand,isusedtobuilddykes.FigureB.21Indicateschangesindesignthatarerequiredwhenoverburdenissubstitutedforsand.

MFT


Compactedsanddyke

MFT

CompactedOverburdenDyke

Chimneydrain

Beachbufferzone


FigureB.21CrosssectionoftailingsdykeChangeindykedesignifthereisashortageofsand

Nobeach

Watercap

Traditionalconstructionwithtailingssand

ChangeifsandisrequiredforCT

Constructionwithoverburdenismoreexpensivethanbuildingwithsand.Activitiesthataddtothecostofconstructingearthstructureswithoverburdenvs.sandaresummarisedinTableB.8.TableB.8Additionalcostsincurredwhenoverburdenisusedtobuilddykesinsteadofsand Earthdykesaremorecomplicatedthanthosebuiltofsand(Fig.B.21). Mustinspectandidentifysuitablematerialforconstructionattheborrowsource. Mustselectivelyloadconstructionmaterialfortransport.

Transportingtheselectmaterialtotheconstructionsiteinvolves:

extrahauldistanceand transportbytruckinsteadofbypipeline

B.9TailingsDams


Placematerialwhereneeded.Compactmaterial(probablybydriving400tontrucksoverit).Withnobeachtherewillnotbeanyfinescapture.ThatcouldincreasetheMFTby30%.

Theaddedcostoftheprecedingstepscouldbeafewdollarspercubicmetreofconstructionmaterial.

B.9.3Constructingretentionfacilitiesinpit.Dykesareneededtoseparatewastestoragefrommineoperationsinpit.FigureB.11.showedhowtailingsandminingworktogetheratSyncrude(Fair,2008).Notallwasteisfluid.FigureB.22illustratesthedifferenceinapproachusedtostorefluidwastevs.materialthatisstrongenoughtobeselfsupporting.

FluidWaste

Openminearea Dyke

OpenMineArea Stackable

solidwaste

Figure B.22Showingdifferentcontainmentrequirements

ToeBerm

B.10ProcessestodensifyMFT

The Rock DoctorB.10ProcessestodensifyMFTPage34

B.10ProcessestodensifyMFTAppendixB.4describesSoilPropertiesandBehaviour.Itsupplementsinformationprovidedinthischapterandisrecommendedreading.Thenovicemaywishtoreaditbeforereadingthischapter.

B.10.1DirecttreatmentprocessesMFTisaliquidthatwillrequireconfinementandsupportuntilitbecomesaselfsupportingsolid.FigureB.23summarizesthebehaviourofasuspendedsolidasthesolidcontentchanges.

FigureB.23Relativevolumesofmineralsolidandwaterinfluidtailings

DataplottedonFigureB.23Include

1. Thesolidcontentincreasesfromlowvalueswithliquidlikepropertiesatthetopofthepagetosolidmaterialwithstrengthatthebottomofthepage.

2. Horizontalbarsacrossthepagerepresenttherelativeamountofwaterandsolidcorrespondingtothesolidorwatercontentindicated.



3. Themiddlecolumndescribesbehaviourofasettlingsolidasitprogressesfromaliquidtoasolid.

4. ThecolumnontherightdescribesmechanicalprocessesthatcanbeusedtodensifymaterialslikeMFTandindicatestherangeofeffectivenessofeach.

5. Thecolumnontheleftshowsnaturalprocessesthatdensifysuspensions.ItalsoindicatesthewatercontentofMFTandthetargetforsolidMFT.

Horizontalbarsrepresentthevoidratioofcorrespondingmaterial.Thevoidratioisdefinedasthevolumeofvoidsperunitvolumeofsolidmaterial.Thetopbarcorrespondstosuspendedsolidsenteringthetailingspond.Ithasasolidcontentof5%to10%andavoidratioof24.Thatmeans24volumesofwaterperunitvolumeofsoil.MFTisshown,withasolidcontentof30%andavoidratioof6.Thetargetmaterialforreclamationasasolidmaterialhasasolidcontentofabout30%andavoidratioofabout1.5.

B.10.2BehaviourasMFTdensifiesMiddlecolumnbehaviourThemiddlecolumndescribesthebehaviourasamaterialchangesfromadiluteslurrytoasolidstrongmaterial.Atthetopofthechartparticlesexperiencefreesettlinginwater.Thenextstateishinderedsettlingasparticlesbecomemorenumerousandinterferewitheachother.Finallyatabout30%solidssettlingstopsbecauserepulsiveforcesbetweenparticlespreventadenserpacking.30%solidscorrespondstoMFTwhereasoilskeletonandthebeginningsofstrengthdevelop.Withincreasingdensity,strengthdevelopsandthebehaviourprogressesfromliquid,toplastic,tosolidbehaviour.Theliquidlimitandplasticlimitsdefinethewatercontentbetweenthosezones.

B.10.3MechanicalprocessesThecolumnontherightofFigureB.23progressesfromgravitysettlingtomechanicalprocessesthatarelistedinorderofcapability.



ThickeneroperationsThickeneroperationusuallyinvolvesdilutiontoabout10%solidtoseparatesuspendedparticlesinalargediametertank.Aflocculentisaddedtodrawtheparticlesintoagglomeratesthatbehaveaslargerparticles.Gentlestirringbyrakesatthebaseofthethickener,sometimesaidedbysandaddition,andbytheweightofoverlyingmaterialforcingflockedmaterialtotheoutletinaconicalbaseaiddensification.Thenormalprocessingyieldsadensityofabout30%solids.Higherdensitiesarereportedbutmaybeduetotheadditionofsand.AsnotedinSection4.1ofAppendixB.4,addingsandaddstomassandtovolumebutnottostrengthatlowsandtofinesratios.Thetypicalresidencetimeinathickenerishalfanhour.IttakesafewyearstoachievethesamedensityinatailingspondTheadvantageofthethickeneristhatitrecoversprocesswater,withitscontainedheat,thatcanthenberecycledandreused.Anotheradvantageofthethickeneristhatitdensifiestheplantstailingsoutletstream.Thatenhancesfinescaptureinsanddeposits.ThecapturedfinesarenotavailabletomakeMFT.Superflocculatingagentsmayachievehigherdensitiesbutareapproachedwithcautionincasethepresenceofthesuperflocinreturnwateradverselyaffectsextraction.(Gu,2009).FilterbeltAfilterbeltisaporousbelt.Inoperationasandblanketisplacedonthebelt.Thenfinesaretreatedwithacoagulantandplacedontopofthesandblanket.Thecoagulantreleaseswaterfromthefines.Suctionappliedtothebottomofthebeltremoveswaterfromthematerialbeingtreated.Thesuctionforceisnotgreatbutitonlyhastoactonanarrowthicknessofmaterial.Filterbeltshavebeenproposed(FineTailsConsortium1995e)buthavenotbeenusedincommercialoilsandprocessing.Concerns:verylargeareasofbeltarerequiredtoprocesslargetonnagesoffines.Inaddition,bitumenfromextractioncouldeasilyclogthebelt.FilterpressAfilterpressexertsahighmechanicalforceonasmallareatocompresssolidsandforcefluidfromthem.Theyarerelativelysmallunitssohavenotbeenusedinoilsandprocessing.CentrifugetreatmentCentrifugesapplythousandsoftimestheforceofgravitytoextractfluidfrommaterial.Theoutletstreamsyieldssolidsatadensityofabout60%.Theotherstreamyieldswater,bitumen,andaminoramountoffines.



Centrifugesareusedextensivelyinoilsandfrothtreatment.TheyhavenotbeenusedcommerciallytoprocessMFT.Centrifugeshavebeensuccessfullypilotedindemonstrationplants(Fair,2008)(Loganet.al.1984).However,testingatfullscaleisneededtoproperlyevaluatethepotentialofthistechnology.BruteforceheatingThehighestlevelofmanmadedensificationinvolvesbruteforceheating.Itistooenergyintensiveandexpensivetoconsider.Theprecedingtechnologiesofferaprogressiveapproachtodewateringfines.Twocautions:

Sandadditioncanaddtodensitywithoutaffectingstrengthandneedstobeunderstood. Chemicalaidscanlowertheliquidlimit,andinturnchangesolidcontentatthetargetstrength.

B.10.4Naturalprocesses.TheleftcolumnofFigureB.23showsnaturalprocessesthatdensifyfines.SedimentationDilutesuspensionsaredensifiedbynaturalsettlementandsedimentation.Asettlingparticlepassesfromadilutesuspensionwhereitisunaffectedbyneighbours,toatransitionzonewhereotherparticleshindersettlement.Whenthedensityreaches30%solidsinterferenceandrepulsiveforcesbetweenparticleshaltfurthersedimentation.ThatmaterialisknownasmaturefinetailsorMFT.ConsolidationConsolidationprocessesaredescribedinSection6ofAppendixB.4.CurrentmethodsofplacingMFTdonotaidconsolidation.Itisnotlikelytoworkintimeunlesssupplementedbywickdrains.SuctionprocessesNaturalprocessesarecapableofexertingsuctiontodensifyadepositofMFT.Underidealconditions,suctionashighas10atmospherescanbeexertedthroughdrying,hydroponics,freezethaw,orbyaddingdryswellingclay.Applicationofsuchlargeforcesisenoughtocompressafinegrainedsoiltoadense,strongstate.Dryingtreatmentinvolvesremovingsurfacewaterandlettingtheexposedsoliddryout.Thetreatmentisasurfacephenomenonsoonlythinlayers(e.g.20cmthick)canbetreatedandrepeatedthroughthe



summer.Thesiteisslopedtofacilitatesurfacedrainage.Largeareasarerequiredtotreatlargequantities.Hydroponicsinvolveusingplantstoexertsuctiononadepositoffines.TheplantscanprocessadeeperprofileofmaterialbutarestilllimitedbythinsurfaceeffectsandtheverylimitedgrowingseasoninFortMcMurray.Whenasoilfreezeswaterisattractedtothefreezingfrontwherepureiceforms.Thesuctionexertedoverloadsandcollapsessoilstructure.Whenthematerialthaws,icemeltsandthewaterisdrainedoffbeforeitcanbereassimilatedinthesoil.Asignificantthicknessofmaterialcanbetreatedbyfreeze/thawiftheprocessesisrepeatedontopofapreviouslyfrozenlayer.Thelimitofhowmuchcanbetreatedperyearisprobablyrelatedtohowmuchcanbethawedthefollowingsummerseveralmetres.Dryswellingclaywouldliketoabsorbmoremoisture.IfblendedwithMFTitwillextractwateruntilthewatercontentofthetwomaterialsreachesastateofequilibrium.Thedryingcapabilityofthistechniqueisquitehigh,anddryswellingclaysareabundantinoverburdeninthemineableoilsandsarea.Thisprocessisnotasurfacephenomenonsocanbeappliedtoanythicknessofmaterial.Themainapplicationfordensificationbyblendingwithswellingclaymayberemovingthelastbitofwaterrequiredtomeetstrengthtargets.Theprecedinglistshowsmechanicalandnaturalprocessesthatcandensifyfines.Itisunlikelythatmechanicalprocessesalonewillbeabletoachievethedensitydesiredforsolidwaste.Naturalprocesseswillhavetobeusedasthefinishingprocess.Thesodiumadsorptionrationofmaterialproposedfortreatmentbysuctionbasedprocessesthatrelyonnaturalwaterrunoff.(seeAppendixB.4).Soilswithahighsodiumadsorptionratioarehighlyerosivesowilltendtoberemovedbyrunoffwater.ItisunlikelythattherewillbeoneSilverBullettomeetalldensificationneeds.Itismorelikelythataprogressionofprocessesshouldbeusedwitheachworkinginthezoneinwhichtheyaremosteffective.

B.10.5MixturesPasteandCT



ThissectiondescribedcombinedprocessesthatareusedtodensifyMFT

Pasteisablendofcoarseandfinegrainedtailingsmaterial.Pasteisnonsegregatingoverarangeofmixesandthatpropertyisusedtoadvantageintransportation,depositionandconsolidationoftailings.

Theuseofnonsegregatingmixesischangingtailingspractice.CTisanonsegregatingmixandisdescribedbelow.

TheCTprocesswasdevelopedattheUniversityofAlbertainthelate1980s(Caughilletal.,1993).Itmeetstheminersdreamofcreatingaproductthatcanbepumpedtothedisposalsite.AtthedisposalsiteCTreleasessurpluswaterandconsolidatestoasolidstatesuitableforreclamation.Atleastthatswhatoperatorshopewillhappen.

SomeoperatorsusevariationsofCTandcallitNonSegregatingTailsorNST.Theprocessesaresimilar.

CTiscreatedandusedasfollows:

MFTistreatedwithacoagulant(gypsum)andthenblendedwithsand. Theblendcreatesanonsegregatingmixforsandtofinesratiosovertherangeof3to6. Theresultingslurryisanonsegregatingblendthatcanbepumpedtoitsdisposalsite, Atthedisposalsiteitflowstoitsfinalrestingplace,againwithoutsegregating, Inplacethedepositslowlyreleasesexcesswater.Initiallyitreleasesexcesswater,andthen

waterreleasedbyconsolidation.

Afivemetersurchargeofsandisappliedatsurfacetoaccelerateconsolidationandtoprovidedesiredstrengthintheupperlayers.

Intime,thedepositconsolidatestoastrong,selfsupportingsolid.

TableB.9showstherelativevolumesassociatedwithCTmanufacture.

TableB.9RelativevolumesintheCTmakingprocess

Parameter Volumem3

SolidContent

Sand/finesratio

Timetoconsolidate

MFT 1.00 30%

Sand 1.27 72%

CTslurry 2.27 57% 4.5

CTdeposit 1.27 80% 4.5

Waterrelease 1.0

Estimatedtimetoconsolidate

4.0 10years



Estimatedtimetoconsolidate

5.0 5years

CTdepositsarefluidsorequirecontainmentforseveralyearsuntiltheyconsolidatetobecomesolidselfsupportingdeposits.

DespitemanyyearsofcommercialusethathasproducedtensofmillioncubicmetresofCTtheprocessisstillunderreview.Apparentlyoperatorshaveexperienceddifficultymaking,transportingandplacingonspecCT.AccordingtoHoulihanet.al.(2008),after10yearsofcommercialuse,Suncoronlyachieved20%ofplannedproductionin2005.

TheCTprocessisanimportantpartofmanycommercialapplications.However,thereisaseverelackofpublicinformationabouttheresearchbehindtheconcept,howitissupposedtowork,thetargetstrengthforprocessedmaterial,operatingperformance,whatsuccessindicatorsarebeingused,andtheprobabilityofsuccess.

AzamandScott,(2005),developedaTernaryDiagramtomapthebehaviourboundariesofanonsegregatingmix.Itisathreedimensionalplotofsand,finesandwatercomponentsillustratedonFigureB.24.



BoundariesthatcanbemappedontheTernarydiagraminclude:

Thesandmatrix, Thefinesmatrix, Wheresedimentationoccurs, D=segregatingvs.nonsegregatingmixes, Pumpablevs.nonpumpablemixes, Saturatedvs.nonsaturatedmixes.

ForCTmanufacturetheboundaryofgreatestinterestistheboundarybetweensegregatingandnonsegregatingmixes.Thatdefinesasmixofmaterialsthatcanbepumped,depositedandallowedtoconsolidate.TheTernaryDiagrammaybeanoversimplificationofmaterialproperties.Anewchartisneededwhenevertheclaycontentorclayactivitychangesinthefinesrepresented.TableB.10summarizesconcernswiththeCTprocessingoption.TableB.10ConcernswiththeCTprocessingoption

Demandexceedssandsupplyo Thedesiredsandtofinesmixis4and5.o Thesandtofinesmixoforeaveragesbetween4and5.o Anoperatingefficiencyof100%wouldberequiredtoprocessallMFT.o AsupplementalsourceofsandwillbeneededtotreatthestrandedMFTinventoryor

Requireanotherprocesstofinishthejob. CTrequirescontainmentuntilitconsolidates.Containmentisexpensive. AttemptstoassignallsandtoCTproductionarecounterproductive

o Requiresdykeconstructionwithoverburdenmuchmoreexpensiveo LosebenefitoffinescaptureinsandthatmayincreaseMFTmakeby30%o Losesafetyfeaturesthatbeachesaddtoretainingstructures.

CTperformanceafter10yearsofcommercialoperationhasnotbeendisclosed. Sulphateadditionmaybefoodforbacterialactionundesirable. Concernsthatthetreatmentisreversiblehavenotbeenansweredinpublic.

B.11StoringMFTunderawatercap

The Rock DoctorB.11StoringMFTunderawatercapPage42


B.11.1 Permanentstorageunderawatercap

In1992SyncrudeproposedtosolidifyMFTusingCTtechnologyandtopermanentlystoresurplusfluidtailingsunderawatercap.

Severalearlypapersdescribetheconceptandstudiesundertakentoconfirmitssuitability.(Nixetal,1988),(Boergeretal,1990),(MacKinnonetal,1991),(Boergeretal,1992),(Gullyetal,1993),(MacKinnonetal.,1995),Thepapersarefoundindiversepublications.Mostoftheauthorsarecloselyrelatedtoprojectsthatstandtobenefitfromthepractice.

AkeyrequirementnotedintheearlypapersisthatthereshouldbenomixingbetweentheMFTandtheoverlyingwatercap.Thepapersexploredpossiblemixingbytheactionofsurfacewaves,andthedesigndepthofthewatercapwassettoat9metrestopreventsuchmixing.Theresearchersconcludedthatgasevolutionfrombiologicalactivitywasunlikely!Inthemid1990smethaneproducingbacteriabecameactiveinSyncrudesMildredLakeBasinandvigorousbubblinghasbeenongoingsince.Limitedresearchrecognizethebacterialactivityandnotethatitcouldaffecttheviabilityofthepermanentstoragescheme.(Holowenko,2000),(Li,2008).Differentbacteriaareactive,consumingdifferentfood(naphtha(solventloss),sulphate(usedinCT),andsodiumcitrate(addedatAlbianSandstoaidextraction).Theauthorwasunabletolocatepublicationsthatshowwhygasreleasefrombacterialactionshouldnotbeaconcern.SyncrudeshowedtheviabilityofstoringMFTunderawatercapinsmallpits.Thedemonstrationpitsprecededbiologicalactivity.AfullscaletestisplannedintheSyncrudebaseminelakestartingin2012.TheexperimentwillinvolveplacingprocessaffectedwaterontopofMFTandobservingbehaviouroverthenextdecade.Furtherdetailshavenotbeendisclosed.Themostrecentpublicationontheendpitlakeconceptprovidesanupdateontheconceptandresearch(ClearwaterConsultants,2007).ThepaperquotedSyncrudereferencesextensively.Itnotesthatitmaybedecadesorlongerbeforetheendpitlakewillqualifyforareclamationcertificate.Itdidnotevenmentionbiologicalactivityorstandardsthatgovernsafelocationsforperpetualstorageoffluidwaste.Thosefactorsreallyneedtobeaddressed.OneaspectofasuggestedguidelineforsafesitesforpermanentstorageoffluidtailingsisprovidedinFigureB.25.



Sethisuggeststhatthatongoingbubblingrepresentsastateofflux.Hesuggeststhatbacteriashouldbeputintoadormantstate.(Sethi,2009).

FigB.25Suggestedoffsettoprotectagainstlongtermgullyexposure

BaseLevel 1o

Containment

Reclaimedcap

WeakTailings

Protectedzone

Vulnerablezone

Challenges:

1. Thereisnopublicdocumentationoncriteriaforasafesurfacestoragesitetoholdcontaminatedfluidinperpetuity.Twosuggestionsforsiteselection:

a. Mustnotbelocatedonasitewheregroundwatercoulddischargeatsurface.MostlocationsneartheAthabascaRiverarepotentialgroundwaterdischargesites.

2. Thesiteshouldbesafefromfutureexposurebyerodinggullies.AsuggestedsafegeometryIndicatedonFigureB.25.FluidshouldnotbestoredabovealineslopingupwardfromanadjacentstreamorfromtheAthabascaRiverbaselevel.Theinclinationoftheslopinglineshouldbesetbequalifiedprofessionals(geographers,engineeringgeologists)andtheirviewofthepotentialforlongtermgulleyerosion.Theauthorsuggeststhatinsandysoiltheexpectedslopeshouldbe1%orless.

3. Thereislimitedpublicpeerrevieweddocumentationdiscussingtheconcept,ofrecentverificationprograms,orofcontingencyplans.



4. Biologicalactivityinthefluidtailingsemitsconsiderablegascapableofmixingfluidtailingswithoverlyingwater.Littleifanypublicdisclosureoffieldperformanceandwhydevelopersconsiderthistonotbeaproblem.Canweevenpredictfutureperformanceaslongasgasemissionsareongoing?

5. Waterreleasefromconsolidationhasbeentakingplacefor40years.Ithasapparentlyincreasedbyordersofmagnitudesincethebiologicalreleaseofgasesshortenedthedrainagepathforreleaseofconsolidationwater.Thereislittleifanypublicinformationontherateoffluidemissionsfromfluidtailings.

6. In1992SyncrudeproposedtosolidifyMFTusingCT.Sincethentheyhaveonlytreated10%oftheMFTcreated.Whathappenedtotheoriginalpromise?

7. RegulatorshavenotapprovedpermanentstorageofMFTunderawatercap.Insteadtheyhaveadvocatedasolidtrafficablelandscapeinstead(Houlihanetal,2008)

8. Thereisnopublicinformationonhowfinancialassuranceisbeingprovidedtoensurethatstrandedfluidtailingswillbesatisfactorilydealtwith.ThetopicrequiresdisclosurebecausethelargestownerofSyncrudeisaTrustwithnoothersourceofincometofundreclamationobligations.

B.11.2EndpitlakeAttheendofoperationsthelastmineopeningwillbeusedasanendpitlake.Runofffromsitesurfaceandgroundwaterwillbedirectedtotheendpitlake.Accumulatedwaterwillbemonitoredforquality,priortodischarge.OperatorsalsoplantopermanentlystoreMFTinthebaseoftheendpitlake.

Itcouldbeseveraldecadesbeforethewaterintheendpitlakewillbereadyforrelease.(ClearwaterConsultants,2007).

Thereislittlepublicinformationabouttheendpitlakes.Keyconcerns:

Whenwilltheconceptbesharedwithpublicstakeholders. Whatistheexpectedquantityandqualityofwaterthatwillenterthelakes. Whatstoragecapacitywillberequiredtoholdrunoffuntilwatercanbedischarged?Creating

storagetohandledecadesofrunoffaforecastbyClearwaterConsultantscouldbeaseriouschallenge.

Arethereplanstotreatwateriftheendpitlakesdonotselfcleanse? Whatarethecontingencyplans? Howdowefundclosureoperationsandcontingencyplansthatwilltakeplacedecadesafterthe

Operationsandincomeareover.

Theendpitlakeproposalappearstobeahighriskoption.AddingMFTstoragetothebaseofthelakeaddsanunnecessarycomplication.

B.12Worldtailingspracticesandimage

The Rock DoctorB.12WorldtailingspracticesandimagePage45

B.12Worldwidetailingsmanagementpractices.

Itisinstructivetoexplorehowtheworldwideminingmanagestailings.

ThekeynoteaddressatPaste08,anannualinternationalminetailingsconference,presentsanunflatteringsummaryofcurrentinternationaltailingsmanagement.(Bogeret.al.,2008).Highlightsofthekeynoteaddressfollow:

Themineralsindustryistheworld'slargestproducerofwaste. Therehavebeensignificantimprovementsinthickeninganddewateringtailingsthatofferand

potentialsavingsinreclamationandenvironmentalmanagementcosts. However,anemphasisonexpendituredeferralpromoteslowcapitaltailingsdisposalsolutions. Tailingsstoragefacilitiesallowwastestorageforalongperiodoftimewhiledeferring

expenditureonreclamationuntiltheendofmining. Alargepartoftheindustrystillcontinuestopumplowdensitymaterialtoverylargedisposal

dams.Thedamsgetbiggerandbiggerandrepresentasignificantrisk.Theyalsorepresentasignificantcostwhenthetimecomestoreclaimthem.

Concernswithtailingsdamsincludeatendencytoleakandapotentialforcatastrophicfailure.Twostandardsgovernfinancialreportingrequirements:"USbasedFinancialAccounting

Standard143:AccountingforAssetretirementObligations(SFAS143)andtheInternationalAccountingStandard37:Provisions,ContingentliabilitiesandContingentAssets(IAS37).Bothstandardsrequirethatreclamationliabilitiesberecognizedonthebalancesheetassoonastheliabilityisincurred,andfortheamounttobediscounted.InadditionSFAS'43requirestheestimatebeincreasedbythetheoreticalcostofsettlingtheliabilitywithathirdpartyinordertoestablishamarketvaluefortheliability.

o Generallyfuturereclamationliabilitiesarecomputedasfollows:o Thefuturecostofreclamationisdeterminedbyinflatingcurrentcoststothefuturedate

whenreclamationmightoccur.o Thefuturecostisthendiscountedbacktotodaybyapplyingasignificantdiscountrate

eachyear.o Discounting,overthelongtimeframetypicalofminingventures,reducesthe

reclamationliabilitytoanegligibleamount.o Discountingisasystematicbiastowardshorttermprofitability.o Historically,industrywideenvironmentalimprovementshavebeenachievedthrough

mandatingrequirementsviaregulation."

TableB.11summarizessomesideeffectsofdiscountingoverlongperiodsoftime.

B.12Worldtailingspracticesandimage

The Rock DoctorB.12WorldtailingspracticesandimagePage46

TableB.11Effectofdiscountingoverlongperiodsoftime.

Discountingseverelyreducestheapparentcostoffuturereclamationliabilities;Discountingjustifiesdeferringreclamationandmaximizingshorttermprofits;Reducingthecostoffuturereclamationliabilities:

o Reducestheneedtosetfundsasidetomeetfutureobligations,o Reducestheneedtoverifythefeasibilityofreclamationandclosureplans,o Reducestheincentiveforresearchtofindabetterapproach,o Createsfalseshorttermprofitsthatrewardthosewhomanagethediscountdeception.

Buildinglargeinventoriesoffluidtailingscreatesriskof:o Accumulatinglargerandlargerliabilitiesthatwillhavetobedealtwithinfuture,o Increasesriskofseepageorcatastrophicfailure,o Thedeveloperbeingunabletopayforthereclamation,o Accumulatedliabilitiescauseaprematurehalttooperationsiftheyexceedfuturevalue,o Untestedreclamationplansmaynotbefeasible.

ThecurrentapproachiscontrarytotwounderlyingprinciplesoftheAPEAAct(Alberta,1993): FailuretodisclosereclamationtechnologyandplanspreventsAlbertansfromproviding

inputtoreclamationdecisions. Deferredreclamationtransfersreclamationliabilitiestofuturegenerations.

Theprecedingactionsarenotwhatthepublicexpectsofresponsiblemanagement.TableB.12summarizessideeffectsofbookingreclamationastheyoccur.TableB.12EffectofbookingreclamationliabilitiestheyoccurbyfundingaQET.

PlacingfundsofequivalentvalueinaQualifyingEnvironmentalTrust:o Recognizesreclamationliabilitiesastheyoccuro Discountingcannotreducethevalueoftheliabilityo Theproceduresetsfundsasidetopayforfuturereclamationactivities.Itdoesnottransfer

liabilitiestofuturegenerations.o Reducesthedeveloperscostofreclamation.QETfundingisanoperatingexpensethat

triggersfiscalsharing.Inthehighlytaxedoilsandsindustrythataverages50%.o Createsanincentiveforprogressivereclamationasithasbeenpaidfor.o Progressivereclamationreducesstockpiledtailingswiththeassociatedrisks.o Progressivereclamationreducestheneedforfinancialassurance.

Withthevalueoftheliabilityretained:o Thereisastrongincentivetoverifyreclamationandclosureplansandtheircosts.o Thereisanincentivetoinvestinresearchtoimprovereclamationandclosureplans.

TheprecedingactionsarecompatiblewiththeintentionsoftheAEPEAAct. Theprecedingactionsarecompatiblewithpublicexpectationsofresponsiblemanagement.

OilsandindustryoperatorscouldimprovetheirimagebyadoptingtheconceptsbehindTableB.12.

B.13Screeningtechnologyoptions

The Rock DoctorB.13ScreeningTechnologyOptions Page47

B.13.1IntroductionThissectionexploreswhatisinvolvedinscreeningtailingstechnologies.Topicsinclude:

Characteristicsofmineableoilsandprojects Typicalstepsinvolvedinscreeningtechnologyoptions Typicalapproachestoeconomicanalysisandtheimplicationstothescreeningprocess Examples Conclusionsandrecommendations AboutQualifyingEnvironmentalTrusts Assigningcoststofuturereclamationobligations

B.13.2CharacteristicsofoilsandprojectsMineableoilsandprojectshaveuniquecharacteristicsthataffecttheappropriateapproachtoeconomicscreening.TableB.13summarizessomeimportantcharacteristicsofoilsandprojects.TableB.14showsthetimelineforsiteuse.TableB.13CharacteristicsofmineableOilSandProjects Largesize, Longprojectlife(upto100years), Largereclamationliabilitieslinkedtoproduction:

- Landdisturbance,- Fluidtailings,- Closurecosts.

Longtimebetweenwhenareclamationliabilityiscreatedandwhenitisdealtwith:- Fluidtailingscurrently25to40+years,- Landreclamationcurrently30to40+years,- Closureactivities50to100years.

Complex fiscal terms that involve capital cost allowances, Alberta royalty, Alberta and Federalincometax,andfiscalsharingofprofitsandexpenditures.Afterpayout,between45%and56%ofprofitandexpensesisdirectedtogovernments,

Ahighproject rateof return isneeded to justify the initial investment and to support the fiscalterms.

TableB.14Typicaltimelineforsiteuse

Year Landuse02 Sitepreparation220 Openpitmine2030 Siteoccupiedbytailingspond



3040 Solidifytailings4050 Reclaimsurface100 Siteclosure

InformationinTables1and2wasderivedfromFair,(2008);Syncrude,(2006);andSyncrude,(2007).Itshowsthatreclamationoftailingsanddisturbed landscanbedelayedby20to50years.Italsoshowsthatclosureactivitiescanbedelayedbyupto100years.

B.13.3.Stepsusedtoscreentechnologyoptions StepsinscreeningtailingstechnologiesareoutlinedinTableB.15.

TableB.15Typicalstepstoscreentechnologyoptions.1. Establishgoalsfortheprojecte.g.

Reclaimtailingsasasolidlandscape. Qualifyforareclamationcertificatewithinafewdecadesafteroperationscease.

2. Identifycandidateoptionsthatwillachievethosegoals.3. Foreachoption:

a. Identifyplanstousetheoptionthroughdevelopment,operationsandclosure.b. Identify full lifecycle capital and operating costs associated with the above. (If we are

comparingoptionsweonlyneedtoidentifycostdifferences.)c. Conductaneconomicassessment.d. Appraisetheprobabilityofsuccess.

4. Choosetheoptionthatwillmosteconomicallymeetprojectgoals.Projectsspendconsiderableeffortexploringtheviabilityofdifferenttechnologiesandtheprobablecostvs.time.Equivalenteffortshouldbespentevaluatingtheeconomicevaluationprocessbecause itcanhaveamajoreffectontheoutcomeofscreeningstudies.

B.13.4CharacteristicsofeconomicanalysisEconomicevaluationsappraisethecashflowoverthelifeofaproject.Theyconvertfutureexpendituresto today by applying discounts. All economic evaluations apply some form of discounting to futureincomeorexpenditurestoconvertthemtopresentvalue.FigureB.26shows theeffectofdiscounting todetermine thepresentvalueof futureobligations.Theplotshowsarapiddropinvaluewithtime.Lossisgreatestwhenhighdiscountratessuchas20%or30%areappliedoverlongperiodsoftime.Theyreducethevalueoffutureobligationstonearzeroin20to30years.TraditionaleconomicevaluationoftailingsoptionswouldcombinethetrendsofFigureB.26(effectofhigh discount rates)with the trends of Table B.13 (long time spans). The combination significantly



reducesoreliminatesfutureexpenditureobligations.Thatmeansthatdecisionsaboutthesuitabilityoftailingsoptionsaremadewithoutconsiderationoffutureexpenditureobligations.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

1 11 21 31 41 51 61 71 81 91

Residu

alvalue

%

Timeinyears

FigureB.26EffectofDiscountFactorandTime

30%Discount

20%Discount

10%Discount

5%Discount

2%Discount

TableB.16liststhreeapproachestoeconomicscreeningthatwereusedtoevaluatetailingsoptionsinPartAofthisreport.TableB.16Threeeconomicscreeningmethodsusedtoevaluateoilsandtailingsoptions.

1. Comparetheundiscountedcostdifferencesvs.timeforeachoption.2. Comparetheundiscountedcostdifferencesvs.timeconsidering:

a. Costvs.timeasinmethod1above.b. Recognizethevalueofreclamationobligationsastheyarecreated.c. Deposit an amount equivalent to the reclamation liability as it is created in a Qualifying

Environmental Trust as reclamation liabilities are incurred. Funds can be withdrawn asreclamationisundertaken.

3. Finally, compare leading contenders in a project economic model that duplicates the projectfinancial environment. Themodel considers all applicable fiscal terms such as Alberta royalty,capitalcostallowances,andincometax.

Netpresentvaluecomparisons isoftenused insteadofundiscountedcosts.Netpresentvalueanalysisappliesdiscounting.AsFigureB.26showsdiscountingoverlongperiodsoftimedistortsanddiminishes.thevalueoftheparameterunderstudy.Discountingdoesnotreducefutureobligations ifmethod2.caboveisused.PlacingfundsinaQualifyingenvironmentalTrustretainsthevalueofthereclamation.



Method three is required to verify that the conclusions of simple screening test still apply to thecomplexfiscalenvironmentthatappliestooilsandsprojects.AppendixB.1 contains electronicmodels that allowuser input to evaluate technology andoperatingoptions.Modelsandspreadsheetsinclude: A spread sheet for each tailings technology studied in Report A. Information includes material

balances, siteactivity,work, capitalandoperating costsvs time foreach technology.Capitalandoperatingcostsaresuggestedbuttheusercaninputtheirownvalueforcapitalandoperatingcostsifdesired.Technologiesarerankedbycomparingtheunitcostofprocessingonecubicmetreofore.

A fullprojecteconomicmodel isprovided. Itaddresses royalty,capitalallowances,provincialandfederal income tax to represent thecomplex fiscalenvironment thatoilsandprojectsoperate in.Tailings technologiesare comparedbyentering technology specific capitalandoperatingcostsvstimeinthemodelwhileotheraspectsofthebusinessareheldconstant.Comparisonoftheoverallproject rateof return foreach technology indicateseconomicperformance. Inputparametersaresuggestedbutthemodelallowsuserstoinputtheirowndataifdesired.

Atailingsforecastmodelisprovided.Itallowsuserdefinedinputtoevaluatetheeffectofdifferentmaterialoroperatingparametersontailingsoutput.

Themodelsandspreadsheetsshowtrends.Theyareprovidedtohelptheuserunderstandtherationaleused toappraise thedifferent tailings technologies.Themodelsshouldalsohelp theuserunderstandthemanyinteractionsinvolvedinevaluatingtailingsperformance.

1.

B.13.5ResultsofscreeningstudiesScreeningtailingstechnologiesFigures A.19 and A.20 from Section A of this report are repeated below. They show the effect ofscreeningcostdifferencesusingundiscountedunitcosts.Netpresentvaluecomparisonyieldsthesametrendsifmethod2.CofTableB.16isused(fundaqualifyingenvironmentaltrust)



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FigureA.19CostDifferencesBetweenTailingsTechnologiesComparescostsforcapital,operations,relatedtoearthwork,

tailingsandheatloss.

HeatLossCosts

TailingsCosts

EarthCosts

OperatingCost

CapitalCost

BaseCase=conventionaloilsandsplantthatmakesMFTT1 ThickenerwithoutcyclonesT2 Thickenerwithcyclones

CT2 CTPlantprocessingoreandfinesderivedfrom theoreprocessedCent=inplantcentrifugecreating"solidwaste"

Figure A.19 compares undiscounted unit cost for the different tailings technologies. Environmentalcostsarenot includedbecausetraditionaleconomicanalysisdiscountsthemthetrivialamounts.Thismethodfavoursoptionsonthe leftthatpostponespending,stockpilefluidtailings,and insodoing,transferenvironmentalobligations to futuregenerations.The favoured technologiesdonotpreparetheprojectforclosure.

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FigureA.20CostDifferencesBetweenTailingsTechnologiesConsiderskeylifecyclecosts

ClosureFund

WaterTreatmentFund

MFTReclamation

LandReclamation

HeatLossCost

TailingsCost

EarthCost

OperatingCost

CapitalCost

BaseCase=conventionaloilsandsplantthatmakesMFTT1=ThickenerwithoutcyclonesT2 Thickener withcyclones

CT2 CTPlantprocessingoreandfinesderivedfromoreprocessedCent=inplantcentrifugecreatingsolidwaste



FigureA.20comparesundiscountedaverageunitcoststhatrecognizereclama

Documents

report b integrated oil sands tailings treatment technologies march 2010.pdf