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Surface(Placed,Cemented(Paste,Tailings,

Prepared,by,

,,Enviromin,,Inc.1,

Introduction!

Surface(placement(of( cemented0paste( tailings( is( an( innovative( and( logical( application(of( two( proven(technologies:(cemented0paste( tailings(backfill(and(surface(placement(of(paste( tailings.(This(approach(reduces( the( long0term( risks( associated(with( tailings(dams( (subaqueous( tailings( impoundments),( and(lessens(potentially(unfavorable(environmental(conditions(observed(in(traditional( tailings(facilities,(such(as(dust(and(water(quality(impacts.(((Although(this(technology(has(not(yet(been(implemented(at(the(facility(scale,(studies(of(surface(placement(of(cemented0paste(tailings(began(in(the(early(2000s.((Critics(within(the(mining(industry(claim(that(adding(cement(to(paste(tailings(in(a(surface(facility(creates(unnecessary(expense,(yet(the(benefits(of(this(tailings(management(strategy(are(increasingly(clear.(The(United(Nations(recently(published(a(rapid(response(assessment(to(mine(tailings(storage(and(recommends(that(tailings(facility( design(objectives(be( raised( to( the( level(of( “zero0failure”( (“Mine(Tailings(Storage:(Safety( is(No(Accident.”(Roche(et(al.,(2017).((

The(utilization(of(cemented0paste(tailings(in(a(surface(facility,(while(acknowledged(as(a(very(expensive(approach,(is(the(highest(level(of(tailings(safety(management(and(goes(well(beyond(the(recommendations(of(the(2017(United(Nations(report.(This(adaptation(of(proven(best(management(practices(culminates(in(an(industry0led(approach(to(responsible(resource(development.(

(

Effective(tailings(management(requires(consideration(of(operational(design(constraints,(environmental(protection,(regulatory(requirements,(short0(and(long0term(economics,(and(social(expectations,(as(well(as(closure(and(remediation(options.(Public(perception(has(recently(been(influenced(by(catastrophic(failures(of(subaqueous(tailings(facilities,(which(have(received(much(more(attention(than(their(far(more(abundant,(properly0functioning(counterparts.(As(a(result,(there(is(an(increasing(demand(for(proactive(and(innovative(design( to( prevent( such( incidents( (Bowker( and(Chambers,( 2017S( Commonwealth( of( Australia,( 2016S(Franks(et( al.,( 2011S(Roche( et( al.,( 2017S( Schoenberger,( 2016),( which( are( commonly(associated(with(mismanagement(of(operational(water(balance((Adiansyah(et(al.,(2015S(ICOLD,(2001).((

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1!This!report!was!written!as!a!part!of!ongoing!work!for!the!Black!Butte!Copper!Project.!!

Surface+Placed+Cemented+Paste+Tailings+ + +


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Although(most(surface( tailings(storage( facilities(are(safely(designed(and(operated,(maintaining(social(license(to(operate(into(the(future(requires(that(the(mining(industry(consider(improved(strategies(for(surface(tailings(placement.(Innovative(techniques(for(tailings(management(have(been(proposed((Barrera(et(al.,(2015S(Bőhm(et(al.,(2005S(Commonwealth(of(Australia,(2016S(Davies(et(al.,(2010S(Edraki(et(al.,(2014),(including(placement(of(paste(tailings(in(surface(facilities,(which(has(been(implemented(at(a(select(number(of(mines.(More( recently,(cemented0paste( tailings(have(also(been(proposed( for(surface(placement,( to(reduce(potential(flow,(reactive(surface(area,(and(dust(generation.(

Background,

Acid!rock!drainage!

Acid(rock(drainage((ARD)(is(a(common(problem(for(mining(of(sulfide0bearing(rock,(where(extraction(and(crushing(of(rocks(exposes(new(mineral(surfaces(to(oxidative(weathering(and(dissolution.(The(oxidation(of(sulfide(minerals((e.g.(pyrite)(by(oxygen(in(the(presence(of(water(releases(acid,(rust0forming(iron(and(sulfate(salts.(Once(water( is(acidic,(accelerated(weathering(of(minerals(can( lead(to(metal( release(and(accelerated( oxidation.( Some( metals( and( metalloids( can( persist( at( neutral( pH,( also( impacting(downgradient(water(quality.((

(

Tailings( is( the(material( remaining(after(ore(has(been(processed( to( remove( the( targeted(mineral,(e.g.(copper.(Tailings(are(finely0ground(to(maximize(recovery(of(the(desired(mineral,(and(therefore(have(a(high(surface(area(available(for(weathering(via( reaction(with(water(and(oxygen.(The(water(management(of(tailings(facilities(is(a(significant(aspect(of(mine(operations(that(extends(through(the(life0of0mine,(well(into(closure.(Minimizing( reactive(surface(area( reduces( reaction( rates(and( the(potential( for(ARD(and(other(water(quality(impacts.((

Tailings!Management!

Mining( technology( evolves( continuously( through( incorporation( of( advances( in( engineering( and(environmental( management.( Not( unlike( technological( advances( observed( in( vehicles( or( personal(computers,(the(21st(century(mine(is(barely(recognizable(next(to(its(counterpart(from(the(previous(century.(Although(these(advances(have(led(to(global(innovation(in(operational(design(and(management(strategies,(selection(of(tailings(technology(varies(greatly(with(site0specific(variables.(Current(tailings(management(practices(can(be(generally(categorized(by(tailings(properties(and(methods(for(containment(of(tailings.((

Tailings(are(produced(as(a(slurry.(They(can(be(thickened(to(reduce(water(content(prior(to(placement(in(three(types(of(tailings:(thickened,(paste,(and(filtered,(which(vary(in(solids(content.(Other(variables,(such(as(particle(size,(also(influence(classification((Ercikdi(et(al.,(2017).((Slurry(has(the(highest(potential(to(flow(

Schematic!of!oxidative!weathering!of!sulfide!minerals!(e.g.!pyrite)!to!generate!acid.!



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with(gravity,(but( “thickened”(tailings(can(as(well.(Conversely,( filtered( tailings(are( too(dry( to(flow,(even(under(pumping(pressure,(and(must(be(transported(mechanically(with(trucks(or(belts.(((

Paste( tailings,(defined(by( flowability(based(on(a(solids(content(which( is(unique( for(each(particle(size(distribution,(can(flow(with(the(application(of(pressure,(much(like(cake0frosting(which(only(flows(out(of(a(tube( onto( a( cake( under( pressure.( For( paste( tailings,( this( means( that( positive( pressure( pumps( and(appropriate(pipeline(designs(are(required(to(transport(the(material(for(placement.(Paste(tailings(also(do(not( segregate( (by(particle( size)(when(placed,(and(admixtures(and(binders( can(be(added( to( increase(flowability(or(strength(prior(to(placement(underground(as(backfill(or(in(surface(facilities.(

(

Binders(are(materials(added(to(paste(tailings(which(have(cementitious(properties(that(make(the(cured(cemented0paste(tailings(stronger.(Portland(cement(has(been(most(frequently(used,(because(it(has(very(good( binding( capabilities.( However,( economic( considerations,( benefits( of( circular( economy,( and( the(unique(chemistry(of(tailings(often(leads(to(use(of(a(combination(of(binders.(Other(materials(used(in(binder(mixes(include(fly(ash(from(coal0fired(power(plants,(slag(from(smelting,(clay,(as(well(as(newer,(less0tested(materials(discussed(below.(Admixtures(are(another(class(of(materials(added(to(cemented0paste(tailings(that( increase( the(utility( of( the(mixture.( For( cemented0paste( tailings,( admixtures(are( used( to( improve(flowability(for(transport.((

Current,State,of,Knowledge,

The(merit(of(adding(binders(to(tailings(in(order(to(increase(strength(of(the(cured(paste(in(backfill(is(well0established((Tariq(and(Yanful,(2013S(Ercikdi(et(al.,(2017).(Placement(of(non0cemented(paste(tailings(in(surface(impoundments(is(a(well0studied(and(increasingly(common(technology.(Each(of(these(styles(of(tailings( management( offers( distinct( benefits( that( have( been( generally( accepted,( yet( placement( of(cemented0paste(tailings(in(surface(impoundments(has(been(limited,(largely(due(to(cost.(



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A( review( of( the( current0state0of0knowledge(for(each(of(these(technologies(demonstrates(that( the( application( of( cemented( paste(tailings( in( a( surface( impoundment( is( an(innovative( and( effective( use( of( proven(technologies.( ( The( following( discussion(reviews( the( benefits( and( limits( of( the(established(technologies(as(applied(in(active(mining( operations( and( summarizes( recent(research.(

Cemented(paste,tailings,backfill,(,

Benefits!and!limitations!of!cemented5paste!tailings!backfill!!!

Cemented0paste( tailings(backfill( technology(was(used(as(early(as(1957( (Tariq(and(Yanful,(2013)(and(revolutionized(mining.(Today,(it(is(a(common(method(for(underground(tailings(placement:(as(of(2010,(at(least(100(facilities(were(reported(to(employ(paste(or(cemented0paste(backfill(techniques((Yumlu,(2010),(and(that(number(has(undoubtedly(risen.(A(range(of(materials(can(be(placed(as(fill,(including(waste(rock,(paste( tailings,( and( cemented0paste( tailings,( using( a( variety( of( binders.( Widespread( placement( of(cemented0paste(tailings(as(underground(backfill(has(well(documented(benefits,(but(also(some(limitations.(

As( a( result( of( the( broad( acceptance( of( cemented0paste( tailings( backfill( technology,( the( current(understanding(of(this(tailings(management(strategy(is(well(documented(for(active(facilities(and(has(been(thoroughly(explored(in(recent(research.(Case(studies(of(the(use(of(cemented0paste(tailings(backfill(are(available((e.g.(MEND,(2006)(and(not(repeated(here.(This(review(describes(current(goals(for( improved(application(of(this(technology(and(does(not(attempt(to(provide(an(exhaustive(summary(of(cemented0paste(tailings(backfill(research(and(applications.(

Surface(Placed(Cemented(Paste(Tailings( ( (

www.enviromininc.com( 524(Professional(Drive,(Bozeman,(MT((59718( 406F581F8261(

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www.enviromininc.com( 524(Professional(Drive,(Bozeman,(MT((59718( (406F581F8261(

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Research(on(cemented.paste(tailings(backfill(((

Current' research'on' cemented/paste' tailings'backfill' is' focused'on'optimizing'operational'use'of' this'technology,'investigating'influences'on'backfill'strength,'and'evaluating'geochemical'characteristics'and'methods.'The'technical'program'for'the'12th'International'Symposium'on'Mining'with'Backfill'(SME,'2017)'presents'an'overview'of'these'current'topics'in'backfill'research.'Specific'topics'covered'in'recent'peer/reviewed'literature'include'evaluations'of'binder'types'and'contentI'influence'of'particle'and'pore'sizes'on'strengthI'the'influence'of'temperature'on'strength'and'reactivityI'and'geochemical'studies.''

Tariq'and'Yanful'(2013)'conducted'an'extensive'peer/review'of'research'on'various'binders'used'with'paste' tailings'and'concluded' that' the'use'of'Portland'cement'as'a' sole'binder' is' both'unsuitable' for'sulfidic'tailings'and'not'cost'effective.'Rather,'the'inclusion'of'pozzolanic'material,'such'as'fly'ash'or'slag,'with' the' cement' improves' strength' and' reduces' negative' risks' of' internal' disaggregation' due' to'recrystallization'of'sulfate'minerals'(also'known'as'“sulfate'attack”).'The'benefits'of'this'binary'approach'to'binder'mixing'were'confirmed'by'Yilmaz'et'al.'(2015),'who'reported'that'cemented/paste'containing'slag'binders'performed'better,'with'respect'to'consolidation,'than'paste'with'Portland'cement'alone'or'Portland'cement'with'fly'ash.''

In'their'2013'review,'Tariq'and'Yanful'suggest'that'laboratory/based'research'into'the'use'of'innovative'materials'and'more'complicated'binder'mixes'(e.g.'with'more'than'two'components)'is'likely'to'increase,'which'will'lead'to'greater'flexibility'in'tailings'design'and'may'reduce'the'cost'associated'with'cemented/paste' tailings.' Indeed,' more' recent' publications' demonstrate' successful' use' of' innovative' binders'including'phosphogypsum'and'phosphate'tailings,'calcined'hard'kaolin,'and'superplasticizers'(Chen'et'al.,'2017I'Zheng'et'al.,'2017I'and'Mangane'et'al.,'2018,'respectively).''

Chen'et'al.'(2017)'found'that'phosphogypsum'and'phosphate'tailings,'which'are'waste'streams'from'industrial'processes'and'phosphate'mining,'were'not'suitable'binders'on'their'own,'but'worked'well'in'concert' with' Portland' cement' and' lime' addition.' Zheng' et' al.' (2017)' investigated' characteristics' of'cemented/paste'mixtures'made'with'varying'proportions'of'calcined'hard'kaolin'and'Portland'cement.'Their'research'showed'that'use'of'30%'calcined'hard'kaolin'and'70%'Portland'cement'led'to'increased'strength'over'time'and'less'expansive'formation'of'gypsum'than'with'Portland'cement'alone.'

Superplasticizers'are'chemicals'that'are'added'to'cement'mixes'to'improve'workability'(e.g.,'flowability)'under'lower'water'content,'which'is'important'for'placement'of'cemented/paste'tailings.'Mangane'et'al.'(2018)'evaluated' five'different' superplasticizers'as'admixtures' to'cemented/paste' tailings'with'mixed'binders'of'Portland'cement'and'slag.'All'five'superplasticizers'allowed'lower'water'content'and'higher'workability'without'compromising'general'strength.'However,'they'varied'in'workability'timeframe'(how'quickly' the' material' must' be' placed)' and' long' term' strength.' This' study' clearly' showed' that'polycarboxylate'performed'the'best'in'terms'of'low'water'content'and'strength,'and'allowed'use'of'lower'overall'binder'content,'which'indicates'possible'economic'benefits.'

Particle'size'plays'an'important'role'in'the'properties'of'pasted/tailings'and'their'interaction'with'binders.'Yang' et' al.' examined' feasibility' of' super/fine' tailings' for' placement' as' cemented/paste' backfill' and'demonstrated'techniques'for'optimizing'solid'content'of'superfine'cemented'paste'tailings'to'enhance'



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flow' characteristics' and' strength' at' contacts' with' non/cemented' paste' backfill.' They' demonstrated'successful'use'of'super/fine'tailings'in'subsidence'control'with'numerical'modeling'and'showed'that'their'placement'in'cemented/paste'backfill'is'feasible.''

Pore'size'and'structure'within'cemented/paste'tailings'is'intrinsically'linked'to'the'strength'of'the'material'and'under'certain'conditions,'influences'the'long'term'stability'of'the'cured'material.'Sun'et'al.'(2017)'uniquely'applied'an'X/ray'CT'scanning'technology'to'evaluate'the'evolution'of'pore'structures'during'compression' testing.'They'demonstrated' the'application'of'CT'Scanning' technology' for' this'purpose'while'defining'the'microstructural'mechanisms'that'can'lead'to'macroscopic'failure'of'cemented/paste'tailings'in'backfill.'The'authors'propose'to'account'for'diversity'in'chemical'composition'and'particle'size'in'tailings'from'different'sources,'in'future'studies.'

Mine' location'and'hydration'of' cemented/paste' tailings'during' curing' influence' the' temperatures'and'therefore' the' strength' of' these'materials.' Current' research' includes'detailed' investigations' of' curing'temperatures'and'climate'influences'on'cemented/paste'tailings'backfill.'Aldhafeeri'et'al.'(2016)'found'that' atmospheric' and' curing' temperatures' have' different' effects' on' the' reactivity' of' three' types' of'cemented/paste'tailings'with'multiple'controlled'pyrite'proportions'(5,'15,'and'45%).'These'tests'showed'lower' reactivity' in' samples' cured' at' higher' temperatures,' with' some' additional' influence' by' pyrite.'However,' in' samples' cured' at' room' temperature,' higher' ambient' temperatures' during' oxygen'consumption' testing' led'to'higher' reactivity'of' the'samples,'particularly' in'early'stages'of'curing.' In'a'complimentary'study,'Cui'and'Fall' (2016)' reported' that'higher' initial' temperatures'of'cemented/paste'tailings'influenced'various'factors'of'curing'and'thereby'increased'the'strength'of'the'backfill.''

Another'study''investigated'the'effects'of'freezing'on'cemented/paste'backfill'(Jiang'et'al.,'2017).'These'authors' conducted' a' column' experiment' with' artificial' tailings,' and' concluded' that' cemented/paste'tailings'backfill'cured'under'freezing'conditions'exhibited'high'strength,'due'to'ice'formation'within'the'matrix'of'the'cemented/paste,'However,'this'study'did'not'address'the'strength'of'this'material'if'thawed.'All'of'these'studies'investigating'temperature'were'conducted'using'Portland'cement'as'the'sole'binder.''Additional' work' is' therefore' needed' to' study' these' temperature' effects' with' increasingly' common,'complex'binder'mixes.'

Many'of' the'environmental'benefits'of'cemented/paste'tailings'backfill' result' from'alteration'of' tailings'geochemistry'following'thickening'and'binder'addition.'A'great'deal'of'research'has'been'conducted'on'this'topic.'Multiple'overview'publications'discuss'the'influence'of'sulfide'minerals'on'the'reactivity'of'the'cemented/paste'backfill'(MEND,'2006I'Alakangas'et'al.,'2013).'However,'due'to'the'high'variability'in'mineralogy'and'particle'size'distribution,'more'recent'publications'regarding'geochemistry'of'cemented/paste' tailings' backfill' tend' to' be' more' site/specific.' For' example,' Hamberg' et' al.' (2015' and' 2017)'investigated'the'influence'of'reduced'binder'content'and'reduced'water'content'on'arsenic'release''from'cemented/pastes'of'tailings'at'a'Finnish'gold'mine.'The'results'demonstrated'that,'for'these'particular'tailings,'placement'as'cemented/paste'backfill'increased'arsenic'mobility'compared'to'that'observed'in'non/cemented'tailings.'This'was'true'regardless'of'binder'content'and'water'saturation'level,'and'may'reflect'the'enhanced'mobility'of'arsenic'at'neutral'to'alkaline'pH'



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Yilmaz'et' al.' (2014a)' investigated' the'effects'of'curing' cemented/paste' tailings'under'pressure'on'a'variety'of'characteristics,'including'geochemistry,'using'three'binder'proportions'and'three'curing'times.'The''results'of'this'study'indicated'that'longer'curing'time'was'effective'at'reducing'sulfate'release'by'''the'materials'used'in'this'study.'

With' respect' to' advances' in' cemented/paste' tailings'backfill' geochemistry,' recent' research' includes'development'of' improved' testing'methods' that'can'be'more'broadly'applied' to'a'variety'of'sites.'For'example,'Moran'et'al.'(2013)'published'findings'from'a'comparative'study'and'concluded'that'application'of'ASTM'1308'diffusion'test'method'was'an'effective'tool'for'predicting'the'diffusion'of'constituents'from'saturated'cemented/paste'tailings'backfill' (i.e.'post/closure).' In'2016,'Schafer'presented'findings'from'an'evaluation'of'Leaching'Environmental'Assessment'Framework'(LEAF)'method'for'use'in'predicting'environmental' impacts'of'cemented/paste' tailings'backfill'at' the'International'Mine'Water'Association'conference' (Shafer,'2016).'Conclusions' from' this'study' included'assessment' that' the'LEAF'methods'were' suitable' for' providing' necessary' information' for' geochemical' predictions,' and' in' particular,' the'diffusion' test' method' (comparable' to' those' recommended' by' Moran' et' al.,' 2013)' was' most/representative'of'intact'cemented/paste'tailings.'

Research' focused' on' geotechnical' optimization' includes' investigation' of' strength' at' the' interface' of'cemented/paste'backfill'and'natural'rock'surfaces.'(Koupouli'et'al.,'2017)'concluded'that'roughness'of'the' rock' surface'had'a'greater' influence'on' strength' than' curing' time.' Also,' rheology' (or' flowability)'studies'of'solid'content'optimization'have'evolved'(Yin'et'al.,'2012),'allowing'development'and'testing'of''a'model'for'predicting'rheology'of'cemented'paste'backfill'(Lang'et'al.,'2015).'With'respect'to'safety,'Lu'and'Fall'(2017)'tested'a'model'using'lab'and'field'blasting'experiments'to'predict'liquefaction'of'freshly/placed'cemented/paste'backfill'during'operations.''Liquefaction'occurs'when'an'otherwise'solid'material,'usually'partially'saturated'with'water,'loses'strength'and'flows'like'a'liquid.'Their'results'showed'that'only'the'upper'portions'of'freshly'placed'backfill'exhibit'potential'for'liquefaction.'Been'et'al.'(2002)'conducted'a'study'of'the'minimum'proportion'of'cement'required'to'prevent'liquefaction'of'cemented/paste'tailings'backfill'at'the'Neves'Corvo'Mine'in'Portugal,'and'concluded'that'the'minimum'content'must'be'greater'than'1%'to'prevent'liquefaction.'

Extensive' laboratory' studies' and' anecdotal' case' studies' exist' documenting' the' implementation' of'cemented'paste' tailings'as'backfill."However," in"situ' tests'of'existing'cemented/paste' tailings'backfill,'which'confirm'and'extend'lab/scale'testing,'is'more'limited'due'to'the'relatively'recent'use'of'this'method.''Following' the' 2014' collapse'of' a' cemented/paste' tailings'backfill' at' the'Lucky' Friday'Mine' in' Idaho'(resulting'from'underhand'cut/and'fill'mining'methods),'Johnson'et'al.'(2015)'published'an'evaluation'of'strength'and'elastic'testing'methods.''This'work'was'followed/up'with'placement'of'in"situ'instrumentation'to'provide'timely'information'about'the'stability'of'the'backfill'as'operations'continue.'

Two'stopes'in'the'Cayeli'mine'in'Turkey'were'outfitted'with'in"situ'instrumentation'for'monitoring'of'stress'loads'and'temperature'in'the'backfilled'materials'and'the'barricades'(Karaoglu'and'Yilmaz,'2017).'This'in" situ' monitoring' was' conducted' using' two' tailings'materials' (clastic' and' spec)' and' varying' binder'contents.''Results'demonstrated'that'the'temperature'and'strength'of'the'cemented'paste'backfill'were'influenced'by'stope'size'and'by'the'character'of'the'original'tailings'material.'



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Another'study'by'Le'Roux'et'al.'(2005)'documented'comparisons'between'lab/scale'and'in"situ'data'from'the'Golden'Giant'Mine' in'Ontario'Canada.'This'study' identified' challenges' in'obtaining' suitable' field'samples' from' backfilled'material.' They' identified' greater' variability' in' the'properties' of' field' samples'compared'to'lab'samples'and'determined'that'lab/scale'strength'tests'were'conservative.'

Surface(placed,paste,tailings,,

Benefits(and(limitations(of(surface.placed(paste(tailings((

Paste'tailings'are' increasingly'placed'in'surface'facilities.'This'placement' is'distinct' from'conventional'subaqueous'tailings'placement,'because'the'paste'tailings'are'not'submerged'in'water,'but'are'allowed'to'weather'subaerially.'Despite'the'exposure'to'air,'the'low'permeability'of'paste'tailings'limits'oxidative'weathering.'Surface'placement'of'paste'tailings'was'patented'in'1996'(Brackebusch,'1996),'but'the'first'operational'use'did'not'occur'until'2003.'Subsequent'application'of'this'technology'has'shown'that'it'can'be'tailored'to'fit'site/specific'geotechnical'and'environmental'requirements,'and'may'offer'an'innovative'way' to' enhance' economic' efficiency' and'mine' sustainability' (Alakangas' et' al.,' 2013I' Simms,' 2017,'Williams'et'al.,'2008I'Wu'et'al.,'2011).'

These'limitations'and'benefits'are'distinct'from'those'reported'for'cemented/paste'backfill.'For'instance,'this'technology'can'be'implemented'for'open'pit'or'underground'mines.'Williams'et'al.'(2008)'point'out'that'while'seepage'from'surface/placed'paste'tailings'is'extremely'unlikely,'because'they'have'very'low'hydraulic'conductivity'by'design,'any'potential'seepage'to'groundwater'could'be'mitigated'with'the'use'of'clay'or'synthetic'liners.'

Furthermore,' surface/placed' paste' tailings' do'not' require' binder,' thereby' reducing'associated' costs.''Despite' the'benefits'of' placing'paste' tailings' in'surface' facilities,'a' few'problems'with'engineering'of'surface'paste'placement'facilities'persist.'These'include'over/topping,'erosion'of'paste'within'the'facility'(which'increases'pressure'on'dams),'and'potential'for'static'liquefaction'accompanied'by'static'or'seismic'slope'instability.'



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Active'Facility'Descriptions''

Placement)of)thickened)tailings)in)surface)facilities)is)relatively)common,)and)as)a)result)of)developing)terminology,)such) facilities)are)often) (erroneously)) listed)as)surface)paste)facilities.)Placement)of) true)paste)tailings)in)surface)facilities)has)been)documented)at)the)following)locations:))

•) Bulyanhulu,)Tanzania)•) Neves)Corvo,)Portugal))•) Myra)Falls,)B.C.,)Canada)•) New)Jersey)Mining,)Idaho,)USA)•) Cobriza,)Peru)

The)Bulyanhulu)Mine) is) an) active)gold)mine) in)Tanzania,)which)was) the) first) to) implement) surfaceJplacement)of)paste)tailings.)An)initial)report)of)surface)paste)facility)design)and)implementation)for)this)wellJstudied)facility)was)published)in)2003)(Theriault)et)al.,)2003).)The)findings)demonstrate)that)addition)of)the)paste)in)thin)lifts,)with)a)maximum)thickness)of)30)cm,)allowed)for)sufficient)desiccation)(drying))to)provide) required)geotechnical) stability.) Furthermore,) continuous) application) of) these) lifts) on) a)5Jday)deposition)cycle)prevented)oxidative)weathering)of)exposed)surfaces.))The)authors)noted)erosion)within)desiccation)cracks,)and)observed)that)when)the)paste)materials)were)physically)disturbed,)they)became)unstable)and) lost) geotechnical) and)environmental) benefits.)This) facility)has)also)been) the) subject) of)numerous)studies,)and)is)generally)considered)a)successful)facility)(Shuttleworth)et)al.,)2005R)Simms)et)al.,)2005)and)2007R)Theron)et)al.,)2005))

In)2010,)Neves)Corvo,)a)copperJzinc)mine) in)southern)Portugal)owned)by)Somnicor) (a)subsidiary)of)Lundin)Mining),)converted)their)tailings)facility)from)a)subJaqueous)to)a)subJaerial,)surface)paste)tailings)operation.)Significant)research)was)invested)in)development)and)design)for)a)successful)facility,)including)a)feasibility)study,) laboratoryJ)and)fieldJscale)testing)followed)by) implementation)of)a)pilotJscale)paste)plant)and)continuous)monitoring)of)the)active)facility)(Newman)et)al.,)2004R)Verburg)and)Oliviera,)2016).)Despite)the)highJsulfide)content)of)these)tailings,)which)indicates)potential)for)high)environmental)risk,)results) of) these) studies) demonstrate) the) reliability) of) labJ) and) fieldJscale)methods) for) predicting) the)minimized) acid) generation) potential) of) lowJpermeability) sulfidic) paste.) The) success) of) this) facility) is)described)by)Lundin)Mining,) in)plans)for) lifeJofJmine)expansions)which) involve) increasing) the)surface)tailings)facility)by)25)hectares)(Lundin,)2016)and)2017).))

In)North)America,)two)operations)using)surface)paste)placement)are)known)to)exist:)the)Myra)Falls)Mine)in)British)Columbia,)Canada)operated)by)Nyrstar)and)the)New)Jersey)Mill)in)Kellogg)Idaho,)USA)operated)by)New)Jersey)Mining)Company.)The)Myra)Falls)Mine)is)located)in)the)StrathconaJWestmin)Provincial)Park)on)Vancouver)Island,)British)Columbia,)an)environmentally)sensitive)location.)Two)tailings)disposal)facilities) (TDFs)) exist) at) this) site,) both) of) which) incorporate) unique) application) of) paste) technology)(Nyrstar,)2014R)MEND,)2017).)The)“Old)TDF”)was)originally)a)conventional)subaqueous)surface)facility)with)tailings)separated)by)particle)size)and)placed)behind)a)constructed)berm.)However,)beginning)in)2003,)a)new)cell)was)constructed)within)the)Old)TDF)for)placement)of)paste)tailings.)This)paste)placement)increased)storage)capacity)in)the)Old)TDF,)by)allowing)use)of)steeper)slopes,)but)ceased)in)2011)when)the)capacity)of)the)new)cell)was)reached.)Reclamation)plans)for)this)facility)are)currently)under)review.)



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Freed)et)al.)(2012))summarized)monitoring)and)modeling)efforts)in)support)of)closure)planning.)This)study)included)sampling)of)monitoring)locations)around)the)Old)TDF)and)modeling)of)flow)paths)using)historic)monitoring)data.)Finally,)they)present)an)overview)of)the)closure)plan,)involving)various)types)of)cover)to)prevent)infiltration)in)strategic)locations.)

The)second)surface)facility)at)the)Myra)Falls)Mine,)called)the)Lynx)TDF,)is)a)former)open)pit.)Placement)of)paste)tailings)in)this)facility)began)in)2008.)Paste)placement)was)chosen)for)this)facility)to)reduce)the)risk)of)tailings)inflow)into)connected)underground)workings.)To)further)safeguard)nearby)active)workings,)the)initial)lifts)were)placed)as)a)cemented)paste)tailings)plug.)Subsequent)lifts)of)nonJcemented)paste)tailings)were)placed)in)the)Lynx)TDF.)All)future)tailings)are)proposed)to)be)placed)as)backfill,)which)will)allow)concurrent)closure)of)surface)facilities)while)mining)continues)(Nyrstar,)2017).)

A)third)party)review)of)possible)tailings)dam)breach)scenarios)for)this)site)indicated)that)the)most)likely)mechanism)for)failure)would)be)liquefaction)of) the)pasted)tailings)as)a)result)of)seismic)activity)(BGC)Engineering,)2014).))Erosion)of)the)paste)tailings)surface)within)the)Old)TDF)was)noted,)creating)a)need)to)improve)stability)of)the)embankment)during)closure.))A)rock)layer)was)used)to)remedy)erosion)prior)to)closure.))Some)surface)erosion)was)also)noted)in)the)Lynx)TDF.)))

The)New)Jersey)Mill)is)located)in)Kellogg,)Idaho)and)is)operated)by)New)Jersey)Mining)Company.)Grant)Brackebusch) described) the) two) ore) processing) streams) for) the) paste) tailings) production) in) a) 2014)publication)(Brackebusch)2014).))The)Idaho)Department)of)Environmental)Quality)issued)the)New)Jersey)Mill)an)award)for)their)surface)paste)facility.)The)award)highlighted)the)reduction)of)risk)to)nearby)surface)water)due)to)the) lack)of)water)retention) in)facilities)onsite)(IDEQ,)2014).)Furthermore,)water) is)mostly)recycled)into)the)processing)stream)rather)than)being)placed)with)tailings)in)the)surface)facility.))

Another) documented) facility) is) the) Cobriza) Mine,) an) underground) copper) mine) in) Peru) that) began)placement)of)paste)in)a)surface)facility)in)2004.)Publically)available)information)for)this)zeroJdischarge)tailings) facility)documents) improved) the)operational)safety)and)success) in) tailings)storage) (Gonzales,)2005).))

Numerous)publications)document)placement)of)paste)tailings)in)surface)facilities)with)varying)degrees)of)uncertainty)about)the)actual)implementation.)Hohne)et)al.)(2004))documented)placement)of)paste)tailings)in)an)open)pit)at)the)former)De)Beers)Mine)in)Kimberley)South)Africa,)which)is)currently)owned)by)Petra)Diamonds) and) Ekapa)Mining.) This) report) indicates) successful) placement) of) paste) in) the) former) pit,)following)reprocessing.)However,)a)later)publication,)refers)to)these)materials)as)“highly)thickened”)leaves)uncertainty)about)whether)materials)placed)in)the)pit)were)true)paste)tailings.)The)Pajingo)Gold)Mine)in)Queensland)Australia)was) noted) as) having)a)paste)operation) for) placing)paste) in) a) former) open) pit)(Williams)et)al.,)2008),)though))more)recent)discussion)of)this)facility)has)not)been)identified.)Barrera)et)al.)(2015))also)noted)implementation)of)surfaceJplaced)thickened)and/or)paste)tailings)in)Chile,)but)details)were)not)provided)for)these)facilities.)

)

)



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Research'on'surface6placed'paste'tailings'

In)addition)to)application)of)pasted)tailings)in)the)aforementioned)facilities,)the)placement)of)paste)tailings)in) surface) facilities) has) been) extensively) investigated) for) more) than) 20) years.) The) most) recent)publications)on)surfaceJplaced)paste)tailings)generally)focused)on)flow)characteristics)and)geochemical)performance.))

Bryan)et)al.) (2010)) investigated) the) influence)of)surface)crack) formation)on)sulfide)oxidation) in)paste)tailings)and)the)influence)that)multilayer)deposition)has)on)the)drying)of) freshlyJadded)layers)of)paste)tailings.)They)concluded)that,)despite)the)increased)surface)area)available)for)oxidative)weathering)along)cracks,)no)significant)difference)in)sulfide)oxidation)was)measured.)Furthermore,)they)predicted)that)dry,)underlying)layers)of)paste)tailings)in)a)surface)impoundment)would)lessen)the)drying)of)freshlyJapplied)layers,)and)that)this)effect)could)be)prevented)by)application)of)sand)layers)as)capillary)breaks.))More)recently,)Bascetin)et)al.)(2018))evaluated)the)influence)of)crack)formation)in)a)labJscale)test)of)surface)paste)of)geochemical)parameters)within)a)broader)ongoing)research)program.)This)study)was)the)most)recent)of)many)conducted)by)this)research)group)(Bascetin)et)al.,)2013)and)2014))

Ozdemir)et)al.)(2016))presented)the)results)of)their)rheological)study)of)paste)tailings)specific)to)surface)placement)at)the)2016)SME)meeting.)Their)study)confirms)that)yield)stress)can)be)adequately)predicted)from)slump)tests,)which)are)easily)implemented)and)important)in)predicting)consistency)of)a)paste)for)pumpability.)

In)2017,)Bascetin)et)al.)(2017))published)a)comprehensive)review)of)characteristics)important)to)paste)tailings) placed) at) the) surface,) in) which) they) detail) methods) for) testing) and) predictions.) This) review)includes)details)of)investigations)using)surface)placement)of)paste)tailings.)They)conclude)that)although)surface)placement)of)paste)tailings)provides)economic)and)environmental)advantages)over)other)tailings)management)strategies,)more)information)on)geochemical)and)geotechnical)performance)at)fieldJscale)is)required)to)betterJdefine)appropriate)application)of)this)technology.))

Surface(placed,cemented(paste,tailings,,

Benefits'and'limitations'of'surface6placed'cemented6paste'tailings''

While)no)single)technology)can)address)environmental)concerns)for)tailings)management)at)all)facilities,)addition)of)binders)to)paste)placed)in)surface)facilities)could)reduce)or)eliminate)the)dominant)concerns)of)surface)placement)of)paste)tailings.)Interest)in)placement)of)cemented)paste)tailings)in)surface)facilities)has)been)documented)as)early)as)the)late)1990s)(Cincilla)et)al.,)1997),)and)the)technology)has)been)the)topic)of)research)for)more)than)15)years.)However,)it)has)only)been)partially)implemented)at)the)facility)scale)at)a)single)known)facility.)

Economics)are)the)primary)argument)against)merging)the)two)technologies)of)cementedJpaste)tailings)backfill)and)surface)placed)paste)tailings.)Critics)consider)the)added)benefits)from)binder)addition)to)paste)placed)in)surface)facilities)to)be)too)small)in)comparison)to)the)additional)cost)incurred.))

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Active'Facility'Descriptions''

The)only)documented)application)of)surface)placement)of)cementedJpaste)tailings)is)in)the)initial)lifts)of)the)Lynx)TDF)at)the)Myra)Falls)Mine.))Anecdotal)evidence)of)another)application)of)this)technology)has)been)identified)in)Spain,)but)cannot)be)confirmed.)

This)technology)was)implemented)at)the)Myra)Falls)Mine)to)form)a)foundation)for)subsequent)placement)of)paste)tailings)in)the)Lynx)TDF.))Details)are)provided)above)in)“SurfaceJPlaced)Paste)Tailings:)Active)Facility)Descriptions.”) Initial)deposition) in)the)pit)consisted)of)cemented)paste) tailings) to)eliminate)an)element)of)risk)that)could)not)be)addressed)by)paste)alone.))

Research'on'surface6placed'cemented6paste'tailings'

Researchers)at)University)of)QuebecJAbitibi)have)conducted)a)number)of)wellJdesigned)studies)into)the)various)aspects)of)placing)cemented)paste)tailings)in)surface)facilities,)some)of)which)are)described)here.))These) include) development) of) a) labJscale) method) for) testing) surface) deposition,) evaluation) of)geochemical)properties)in)response)to)binder)proportions,)and)desiccation)crack)formation)(Benzaazoua)et)al.,)2004R)Deschamps!et)al.,)2008R)Deschamps!et)al.,)2011R)Ichrak)et)al.,)2016).)Other)research)groups)have) investigated)binder) types,)climate)effects,)or)compared)the)geochemistry)of)cemented)and)nonJcemented)paste)tailings)(Dinis!et)al.,)2016R)Liu!et)al.,)2016R)Seipel)et)al.,)2017R)Verburg,)2001).))

In)2001,)Verburg)published)a)summary)of)the)proposed)benefits)of)paste)technology)which)specifically)address)the)use)of)binders)for)geotechnical)reasons)that)also)provide)environmental)benefits.)This)report)also) summarizes) labJ) and) pilotJscale) test) methods) for) predicting) geochemistry) of) surface) paste)placement)are)also)relevant)to)characterization)of)cemented)paste)placed)at)the)surface.)

Benzaazou) et) al.) (2004)) described) a) labJscale) method) that) simulated) in! situ) surface) placement) of)cementedJpaste) tailings.)Their) study) included)evaluation)of)deposition,)as)well) as)basic)geochemical)parameters.)The)outcome)of)this)study)yields)a)wellJdocumented)labJscale)design)for)testing)cementedJpaste)placement)in)facilities,)as)well)as)the)general)conclusion)that)addition)of)Portland)cement)reduced)reactivity,)despite)the)formation)of)cracks.)

In)2008,)Deschamps)et)al.)conducted)a)series)of)30Jweek)layered)column)leaching)tests)using)varying)proportions)of)Portland)cement)as)a)binder) in)sulfidic)paste) tailings.)Their)study) included)microJscale)investigation)of)porosity)and)surface)area,)as)well)as)some)geochemical)characteristics.)Overall,) they)determined)that)addition)of)modest)amounts)of)Portland)cement)was)an)effective)way)to)stabilize)sulfide)minerals)in)a)surface)placement)scenario.)Interestingly,)this)study)support)intermittent)addition)of)binder)at)modest)proportions)over)continuous)addition)of)low)proportions)of)binder.)Although)this)is)promising)research,)it)remains)to)be)seen)whether)use)of)more)complicated)binder)mixes)yields)different)results.))

Following)the)2008)column)study,)Deschamps)et)al.)(2011))published)initial)results)of)a)long)term)study)of)labJscale)surfaceJplaced)cementedJpaste)tailings,)which)were)placed)in)strategic)layers)within)layers)of)paste)tailings)using)the)test)apparatus)described)in)Benzaazou)et)al.,)2004.)The)authors)observed)that)the)pH)did)not)drop)despite)the)development)of)preferential)oxidation)paths)and)persistent)desiccation)cracking.))



15(!

!

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Ichrak'et'al.'(2016)'continued'this'study'with'addition'of'a'final'cemented<paste'layer'and'application'of'seven' wetting' and' drying' cycles.' Furthermore,' they' conducted' post<test' examinations' of' the'microstructure'within'the'layers'using'destructive'sampling'techniques.'These'results'indicate'that'drying'of'deeper'layers'of'paste'tailings'appears'to'have'been'inhibited'by'addition'of'a'final'cemented<paste'layer.'The'authors'note'that'desiccation'cracks'appeared'on'the'final'cemented<paste'layer'6'hours'after'placement.'However,' they'note'that' this' layer'was'only'4'cm'thick,'which'may'influence'the'observed'desiccation'and'crack'formation.''

Dinis'et'al.'(2016)'conducted'a'study'of' the'short<term'leachate'and'mechanical'properties'of'surface'paste'with'coal'ash' (a'pozzolanic'binder'material).'There' results' indicate'a'decrease' in'compressive'strength'as'a'result'of'coal'ash'addition.''However'curing'time,'which'has'a'strong'influence'on'strength,'was'not'documented,'so'no'conclusions'can'be'drawn'from'this'aspect'of' the'study.'The'inclusion'of'short'term'leachate'chemistries'does'indicate'that'coal'ash'reduced'weathering,'and'therefore'prevented'increases' in'electrical'conductivity' that'were'observed' in' the'tailings<only'control.'Finally,' fly'ash'was'found'to'be'a'superior'additive'to'bottom'ash,'which'has'a'lower'pH'and'also'yielded'poorer'compression'test'results.''

Liu'et'al.'(2016)'showed'that'cemented<paste'tailings'in'a'surface'facility'is'feasible'in'a'tropical'climate.'This' study' reviewed' optimum' binders' and' erosion' in' response' to' heavy' rainfall.' The' results' of' this'research'show'that'the'right'proportion'of'clay,'which'absorb'excess'moisture,'and'Portland'cement'had'sufficient'flowability'and'strength'for'surface'placement,'and'erosion'was'minimized'after'only'6'hours'of'curing.'The'authors'plan' to'continue' research'and' include'geochemical'analyses' in' future'work.'This'study'is'particularly'interesting,'because'it'addressed'erosion'with'the'application'of'binders,'which'could'be'implemented'in'any'climate'to'mitigate'erosion'from'other'surface'disturbance,'such'as'wind,'thereby'reducing'risk'of'dust'generation'or're<deposition'of'particles'against'a'dam.'

Seipel'et'al.'(2017)'conducted'a'series'of'geochemical'tests'of'high<sulfide'tailings,'showing'that'addition'of'binders'(Portland'cement'and'fly'ash)'decreased'the'reactivity'of'the'tailings.'The'results'of'this'study'demonstrated' the' influence'of' reactive' surface'area'on' the' leachate' chemistry'and'agree'with'other'research'indicating'that'consolidated'cemented<paste'tailings'are'less'reactive'than'non<cemented'paste'tailings.'

At'the'pilot<scale,'Yilmaz'et'al.'(2014b)'investigated'the'effects'of'a'cemented'layer'in'the'lower'portion'of'an'otherwise<not<cemented'paste'surface'deposition'facility.'Because'this'study'was'meant'to'address'transition'of'an'active,'traditional'tailings'impoundment'to'a'surface'paste'disposal'facility,'the'underlying'material'in'both'cells'was'tailings'slurry.'Subsequent'layers'consisted'of'paste'tailings.'They'use'two'field'cells<'one'using'cemented<paste'for'an'initial'paste'layer'followed'by'nine'non<cemented,'or'plain,'pasteQ'and'the'other'cell'consisted'of'ten'plain'paste'layers.'Specifically,'they'investigated'matric'suction'and'volumetric'water'content,'and'cracking.'This'study'was'largely'an'investigation'of'paste'(not'cemented<paste),'yet'the'results'show'that'addition'of'cement'to'at'least'some'layers'led'to'decreased'matric'suction'and' more,' yet' smaller' cracks.' These' authors' recognize' that' they' did' not' address' the' geochemical'outcomes' of' their' study' in' this' publication' and' they' propose' to' do' so' along' with' other' various'mineralogical'evaluations'of'these'field'cells.''



17(

Conclusions)

Based' on' the' current' state<of<knowledge' about' existing' facilities' and' results' of' targeted' research,'integration'of' the' two'technologies:' (1)'cemented<paste' tailings'backfill,'and' (2)'surface<placed'paste'tailings' provides' a' promising' avenue' to' reduce' environmental' liability' and' improve' social' license' to'operate.'Adoption'of'further'strategies'with'added'cost'requires'adequate'evidence'of'benefit,'which'can'only'be'obtained'as'this'technology'is'demonstrated.'Thorough'analysis'of'the'life'cycle'cost<benefit'of'cement' addition' to' paste' tailings' is' warranted.' Available' research' combined' with' extensive' in# situ'demonstration'of'cemented<paste'tailings'backfill'and'surface<placed'paste'tailings'strongly'supports'the'merging'of' these' technologies.'Certain' limitations'of' these' two'well<documented' technologies'can'be'addressed'by'their'integration.'

'Widespread' implementation' of' cemented<paste' tailings' placement' in' surface' facilities' ' is' limited' by'insufficient'long<term'evidence'of'predicted'benefits,'as'well'as'a'lack'of'defined'testing'framework'for'generating' reliable'predictions'of'performance' in'support'of'cost/benefit'analyses.'There' is'a'growing'body' of' knowledge' that' can' be' legitimately' applied' to' implementation' of' this' technology,' as' is'demonstrated'by'this' review.'Research' into'application'of'established' test'methods'shows' that'these'



18(

methods'are'useful'in'predicting'geochemistry'of'paste'and'cemented<paste'tailings'in'various'settings.'Scale<up'for'such'tests'remains'a'key'issue'(MEND,'2006Q'Moran'et'al.,'2013Q'Schafer,'2016Q'Seipel'et'al.,'2017).'The'extensive'work'conducted'at'Neves'Corvo'demonstrates'that'a'multi<scale'approach'to'testing'provides' reliable'predictions' for' facility'design'and'permitting.'Lab<scale' facility'simulations'by'researchers,' correlated'with' in# situ' ' success' at' cemented<paste' tailings' surface' facilities,' will' greatly'reduce'this'barrier'to'entry.''

Other'limitations'of'optimization'and'operational'nature'are'similar'to'those'reported'for'cemented<paste'tailings'backfill.'As'such,' these' limitations'are'already'being'addressed' (e.g.,'use'of'optimized'binder'mixes)' or' are' becoming' less<restrictive' to' due' technological' advances' (economics' of' advanced'processing' technology).' ' Use' of' alternative' binders'which'are'by<products'of' other' processes'offers'significant'efficiency'within'a'circular'economy'context.'

Operational' costs' associated' with' cemented<paste' tailings' technologies,' particularly' in' surface'applications,'are'often'cited'as'a'constraint'for'this'technology.'The'costs'of'generating'paste'tailings,'as'well' as' the' cost' of' binders,' are' quantifiable' costs' of' implementation.' In' the' case' of' backfilling' of'cemented<paste' tailings,' increased' ore' recovery' is' a' calculable' economic' benefit' that' has' generally'outweighed' the'hurdles' to' implementation,' leading' to'widespread'acceptance'of' this' technology.' It' is'more'difficult'to'appraise'components'of'mine'plans'which'influence'cost'indirectly,'such'as'smaller'mine'footprint,'reduced'duration'of'closure,'or'reduction'in'water'quality'impacts'or'long'term'water'treatment'(Boger,'2012Q'Fourie,'2012).'Nevertheless,'there'is'increasing'demand'for'incorporation'of'these'cost<saving'benefits'in'tailings'facility'selection,'making'surface'application'of'cemented<paste'tailings'a'more'viable'alternative.''

A' persistent' challenge' for' mining,' even' in' the' 21st' century,' involves' assurance' of' environmental'protection.'Although'evidence'indicates'that'binder'addition'is'an'effective'way'to'limit'reactivity,'it'cannot'be'eliminated'entirely,'particularly'in'strongly'sulfidic'materials.'In'this'case,'incorporation'of'additional,'technologically<advanced'methods'for'ensuring'environmental'protection'could'be'utilized'in'the'facility'design.'For'example,'a'benefit'of'surface'paste'application'over'backfilling'is'the'possible'use'of'liner'to'isolate'the'tailings'from'the'surrounding'environment.'To'this'end,'placement'of'cemented<paste'tailings'within'a'lined'surface'facility'appears'to'offer'the'best<available'environmental'controls.''

Surface' placement' of' cemented<paste' tailings' improves' the' physical' and' chemical' stability' of'mined'materials,' reduces' their' reactivity' by' minimizing' exposure' to' mine' water' and' minimizing' footprint,'improves'water<reuse,' and' reduces' post' closure' risk.'As' such,' this' technology'addresses' calls' from'multiple' stakeholders' for' improved' sustainable' practices' in'waste'management' (Franks'et' al.,' 2011Q'Boswell'and'Sobkowicz,'2011Q'Taguchi,'2014Q'Adiansyah'et'al.,'2015).'Likewise,'this'technology'offers'improved'potential' to'meet'the''United'Nations'call' for'zero<failure'standards' in'tailings'facility'design'(Roche'et'al.,'2017).'The'preceding'discussion'demonstrates' that' the' integration'of' two'well<studied'technologies,'in'combination'with'other'safeguards'such'as'facility'liners,'is'a'best<management'practice'that'offers'the'greatest'potential'for'a'“zero<failure”'facility.'


Surface(Place(Cemented(Paste(Tailings((

References(

Social'Demand'

1.# Bowker,#L.N.,#and#Chambers,#D.M.#2017.# In# the#Dark#Shadow#of# the#Supercycle#Tailings#Failure#Risk#&#Public#Liability#Reach#All#Time#Highs.#Environments,#v4#p75.#

2.# Franks,#D.,#Boger,#D.,#Côte,#C.,#Mulligan,#D.#2011.#Sustainable#development#principles#for#the#disposal#of#mining#and#mineral#processing#wastes.#Resources#Policy,#v36#p114S122.#

3.# Roche,# C.,# Thygesen,# K.,# Baker,# E.# (Eds.)# 2017.# Mine# Tailings# Storage:# Safety# Is# No#Accident.#A#UNEP#Rapid#Response#Assessment.#United#Nations#Environment#Programme#and#GRIDSArendal,#Nairobi#and#Arendal,#www.grida.no#

4.# Schoenberger,#E.#2016.#Environmentally#sustainable#mining:#The#case#of# tailings#storage#facilities.#Resources#Policy,#v49#p119S128.#

Tailings'Management'Strategies'

5.# Adiansyah,#J.S.,#Rosano,#M.,#Vink,#S.,#Keir,#G.#2015.#A#framework#for#a#sustainable#approach#to# mine# tailings# management:# disposal# strategies.# Journal# of# Cleaner# Production,# v108#p1050S1062.#

6.# Barrera,# S.,# Cacciuttolo,# C.,# Caldwell.,# J.# 2015.# Reassessment# of# best# available# tailings#management#practices.#In:#Proceedings#Tailings#and#Mine#Waste.#October#26S28.##

7.# Boger,#D.#2012.#Personal#perspective#on#paste#and#thickened#tailings:#a#decade#on.#Mining#Technology,#v121#p#29S36.#

8.# Bőhm,#J.,#Debreczeni,#Á.,#Faitli,#J.,#Gombkötő,#I.,#László,#T.#2005.#Sustainable#Improvement#in# Safety# of# Tailings# Facilities# TAILSAFE:# Tailings# Management# Facilities# Water#Management#and#the#Use#of#Thickened#Tailings.#A#European#Research#and#Technological#Development# Project# Contract# Number:# EVG1SCTS2002S00066�Website:#http://www.tailsafe.com/#

9.# Boswell,# J.,# and# Sobkowicz,# J.# 2011.# Duty# of# Care# Applied# to# Tailings# Operations.#Proceedings:#Tailings#and#Mine#Waste#2011.#Vancouver,#BC,#November#6S9.#

10.# Commonwealth# of# Australia.# 2016.# Tailings# Management,# Leading# Practice# Sustainable#Development#Program#for#the#Mining#Industry.#February.##

11.# Davies,#M.P,# &#Lupo,# J.#&#Martin,# T.# &#McRoberts,# E.# &#Musse,#M.#&#Ritchie,# D.# 2010.#Dewatered#Tailings#Practice#–#Trends#and#Observations.#In#proceedings#of#Tailings#and#Mine#Waste#’10,#Balkema.#

12.# Edraki,#M.,#Baumgartl,#T.,#Manlapig,#E.,#Bradshaw,#D.,#Franks,#D.,#Moran,#C.#2014.#Designing#mine#tailings#for#better#environmental,#social#and#economic#outcomes:#a#review#of#alternative#approaches.#Journal#of#Cleaner#Production,#v84#p411S420.#

13.# Fourie,#A.#2012.#Perceived#and#realized#benefits#of#paste#and#thickened#tailings#for#surface#deposition.#The#Journal# of#The#Southern#African# Institute#of#Mining#and#Metallurg,y# v112#p919S926.#

Surface+Placed+Cemented+Paste+Tailings+ + Reference+List+

!


+

14.# ICOLD#2001.#Tailings#dams#risk#of#dangerous#occurrences,#Lessons# learnt# from#practical#experiences.#Bulletin#121.#

15.# MEND,#2017.#Study#of#Tailings#Management#Technologies.#MEND#Report#2.50.1.#October#16.# Simms,#P.#2017.#2013#Colloquium#of#the#Canadian#Geotechnical#Society:#Geotechnical#and#

geoenvironmental#behaviour#of#highSdensity#tailings.#Can.#Geotech.#J.#v54#p455–468.#17.# SME,# 2017.# International# Symposium# on# Mining# with# Backfill.# Technical# Program.#

http://www.smeannualconference.com/ace/includes/themes/ace/img/2017/ISMB/Brochure_TechnicalProgram.pdf#(accessed#January#2018)#

18.# Taguchi,# G.# 2014.# Fault# tree# analysis# of# slurry# and# dewatered# tailings# managementS# a#framework.#Master’s#Thesis#in#Mining#Engineering#from#the#University#of#British#Columbia.#March.#

Cemented'Paste'Tailings'Backfill'

19.# Aldhafeeri,#Z.,#Fall,#M.,#Pokharel,#M.,#Pouramini,#Z.#2016.#Temperature#dependence#of#the#reactivity#of#cemented#paste#backfill.#Applied#Geochemistry,#v72#p10S19.#

20.# Been,#K.,#Brown,#E.,#Hepworth,#N.#2013.#Liquefaction#potential#of#paste#fill#at#Neves#Corvo#mine,#Portugal.#Mining#Technology#Transactions#of#the#Institutions#of#Mining#and#Metallurgy:#Section#A.#v111#p47S58.#

21.# Chen,#Q.,#Zhang,#Q.,#Fourie,#A.,#Xin,#C.#2017.#Utilization#of#phosphogypsum#and#phosphate#tailings#for#cemented#paste#backfill.#Journal#of#Environmental#Management,#v201#p19S27.#

22.# Cui,#L.,#Fall,#M.#2016.#Mechanical#and#thermal#properties#of#cemented#tailings#materials#at#early# ages:# Influence# of# initial# temperature,# curing# stress# and# drainage# conditions#Construction#and#Building#Materials.#v125#p553S563.#

23.# Ercikdi,# B.,# Cihangir,# F.,# Kesimal,# A.,# Deveci,# H.# 2017.# Practical# Important# of# tailings# in#cementedSpaste# backfill.# In# Paste# Tailings# Management.# Eds.# Yilmaz,# E.# and# Fall,# M.#Springer#International#Publishing,#Switzerland.#p7S32.#

24.# Hamberg,# R.,# Maurice,# C.,# Alakangas,# L.# 2017.# Lowering# the# water# saturation# level# in#cemented#paste#backfill#mixtures#–#Effect#on#the#release#of#arsenic.#Minerals#Engineering,#v112#p84S91.#

25.# Hamberg,# R.,# Maurice,# C.,# Alakangas,# L.# 2015.# The# use# of# low# binder# proportions# in#cemented#paste#backfill#–#Effects#on#AsSleaching.#Minerals#Engineering,#v78#p#74S82.#

26.# Jiang,#H.,#Fall,#M.,#Cui,#L.#2017.#Freezing#behaviour#of#cemented#paste#backfill#material#in#column#experiments.#Construction#and#Building#Materials,#v147#p837S846.#

27.# Johnson,#J.,#Seymour,#J.,#Martin,#L.,#Stepan,#M.,#Arkoosh,#A,#Emery#T.#2015.#Strength#and#elastic#properties#of#paste#backfill#at# the#Lucky#Friday#Mine,#Mullan,# Idaho.#49th#US#Rock#Mechanics#/#Geomechanics#Symposium.#San#Francisco,#CA,#28#JuneS#1#July.#

28.# Karaoglu,#K.#Yilmaz,#E.#2017.#Cemented#paste#backfill#testing#and#pressure#monitoring#and#field# testing.# In# Paste# Tailings# Management.# Eds.# Yilmaz,# E.# and# Fall,# M.# Springer#International#Publishing,#Switzerland.#p195S214.#

29.# Koupouli,#N.#Belem,#T.,#Rivard,#P.#2017.#Shear#strength#between#cemented#paste#backfill#and#natural#rock#surface#replicas.#Underground#Mining#Technology.#M#Hudyma#&#Y#Potvin#(eds).#Australian#Centre#for#Geomechanics,#Perth,#ISBN#978S0S9924810S7S0#


!


+

30.# Lang,#L.,#Song,#KSI.,#Lao,#D.,#Kwon,#TSH.#2015.#Rheological#properties#of#cemented#tailing#backfill#and#the#construction#of#a#prediction#model.#Materials,#v8#p2076S2092.#

31.# Le#Roux,#K.,#Bawden,#W.,#Grabinsky,#M.#2005.#Field#properties#of#cemented#paste#backfill#at#the#Golden#Giant#mine.#Min#Technol#Inst#Min#Metall#Trans#Sect#A#v114(2)#p65–80.#

32.# Lu,#G.,#and#Fall,#M.#2017.#Simulation#of#blast#induced#liquefaction#susceptibility#of#subsurface#fill# mass.# Geotechnical# and# Geological# Engineering# https://doi.org/10.1007/s10706S017S0423S5#

33.# Mangane,# M.B.C.,# Arganea,# R.,# Trauchessec,# R.,# Lecomte,# A.,# Benzaazoua,# M.# 2018.#Influence#of#superplasticizers#on#mechanical#properties#and#workability#of#cemented#paste#backfill.#Minerals#Engineering,#v116#p3S14.#

34.# MEND# 2006.# Paste# Backfill# Geochemistry# –# Environmental# Effects# of# Leaching# and#Weathering.#MEND#Report#10.2.#April.#

35.# Moran,# P.,# Christoffersen,# L.,# Gillow,# J.,# Hay,# M.# 2013.# Cemented# Tailings# Backfill# –# It’s#Better,#Now#Prove#It!#SME#Annual#Meeting,#Denver,#CO.#February#24#–#27#

36.# Schafer,# W.# 2016.# Geochemical# Evaluation# of# Cemented# Paste# Tailings# in# a# Flooded#Underground#Mine.#–#In:#Drebenstedt,#C.#&#Paul,#M.:#IMWA#2016#–#Mining#Meets#Water#–#Conflicts#and#Solutions.#–#p.#714#–#724r#Freiberg/Germany#(TU#Bergakademie#Freiberg).#

37.# Sun,#W.,#Hou,#K.,#Yang,#Z.,#Wen,#Y.##2017.#XSray#CT#threeSdimensional#reconstruction#and#discrete# element# analysis# of# the# cement# paste# backfill# pore# structure# under# uniaxial#compression.#Construction#and#Building#Materials#v138#p69–78.#

38.# Tariq,# A.,# and#Yanful,# E.# 2013.# A# review# of# binders# used# in# cemented# paste# tailings# for#underground#and#surface#disposal#practices.#Journal#of#Environmental#Management,#v131#p138S149.#

39.# Yang,# L.,# Qiu,# J.,# Jiang,# H.,# Hu,# S.,# Li,# H.,# Li,# S.# 2017.# Use# of# Cemented# SuperSFine#Unclassified#Tailings#Backfill#for#Control#of#Subsidence.#Minerals,#v7#p216.#

40.# Yilmaz,#E.,#Belem,#T.,#Benzaazoua,#M.#2014a.#Effects#of#curing#and#stress#conditions#on#hydromechanical,# geotechnical# and# geochemical# properties# of# cemented# paste# backfill.#Engineering#Geology,#v168#p23S37.#

41.# Yilmaz,#E.,#Belem,#T.,#Bussière,#B.,#Mbonimpa,#M.#and#Benzaazoua,#M.#2015.#Curing#time#effect# on# consolidation# behaviour# of# cemented# paste# backfill# containing# different# cement#types#and#contents.#Construction#and#Building#Materials,#vol.#75,#pp.#99S111.#

42.# Yin,#S.,#Wu,#A.,#Hu,#K.,#Wang,#Y.#and#Zhang,#Y.#2012,#The#effect#of#solid#components#on#the#rheological#and#mechanical#properties#of#cemented#paste#backfill.#Minerals#Engineering.#v35#p61S66.#

43.# Yumlu,#M.#2010.#Mining#with#paste#fill.#AusIMM#Cobar#Mining#Seminar,#6#August.#44.# Zheng,#J.,#Guo,#L.,#Zhao,#Z.#2017.#Effect#of#Calcined#Hard#Kaolin#Dosage#on#the#Strength#

Development# of# CPB#of# Fine# Tailings#with# Sulphide.# Advances# in#Materials# Science#and#Engineering.#Article#ID#8631074.#

Surface9Placed'Paste'Tailings'

45.# Alakangas,#L.,# #Dagli,#D.,#Knutsson,#S.#2013.#Literature#Review#on#Potential#Geochemical#and#Geotechnical# Effects# of# Adopting# Paste# Technology# under# Cold# Climate# Conditions.#Luleå#University#of#Technology.#


!


+

46.# Bascetin#A,#Tuylu#S,#Adiguzel#D,#Akkaya#U,#Binen#IS.#2013.#Investigation#of#suitability#of#PbSZn# mine# tailings# for# surface# paste# disposal.# 23rd# World# Mining# Congress,# Montreal,#CANADA,#11–15#August#2013,#Paper#301#

47.# Bascetin#A,#Tuylu#S,#Adiguzel#D,#Akkaya#UG#2014.#The#study#of# surface#paste#disposal#technology#for#PbSZn#mine#tailings.#In:#SME#annual#meeting,#Preprint#14–020,#Feb.#23–26,#2014,#Salt#Lake#City#

48.# Bascetin,#A.,#Tuylu,#S.,#Ozdemir,#O.,#Adiguzel,#D.,#Benzaazoua,#M.#2017a.#An#investigation#of#crack#formation#in#surface#paste#disposal#method#for#pyritic#Pb–Zn#tailings.#Int.#J.#Environ.#Sci.#Technol.#https://doi.org/10.1007/s13762S017S1380S5.#

49.# Bascetin,#A.,#Tuylu,#S.,#Adiguzel,#D.,#Ozdemir,#O.#2017.#Field#Properties#and#Performance#of#Surface#Paste#Disposal.#In#Paste#Tailings#Management.#Eds.#Yilmaz,#E.#and#Fall,#M.#Springer#International#Publishing,#Switzerland.#p145S176.#

50.# Bascetin,#A.,#Tuylu,#S.,#Ozdemir,#O.,#Adiguzel,#D.,#Benzaazoua,#M.#2018.#An#investigation#of#crack#formation#in#surface#paste#disposal#method#for#pyritic#Pb–Zn#tailings.#Int.#J.#Environ.#Sci.#Technol.#v15(2)#pp281S288.#

51.# BGC#Engineering,#2014.#Correspondence#from#BGC#Engineering#to#Ivor#McWilliams,#Nyrstar#Myra# Falls.# RE:# 2014# Independent# Review/Audit# of# Tailings# Dam# Safety# Inspection# and#Consequence#Classification:#Myra#Falls#Mine,#BC.#December#1.#

52.# Brackebusch,#F.#1996.#Mineral#processing#tailings#disposal#Patent#Number#CA2192775#C#(Expired#2006).#

53.# Brackebusch,#G.#2014.#Paste#tailings#disposal#in#the#Coeur#d’Alene#Mining#District.#Mineral#Engineering.#v66#p52–56.#

54.# Bryan,# R.,# Simms,# P.,# Verburg,# R.# 2010.# Coupling# oxidation# to# transient# drying# during#multilayer#deposition#of#thickened#gold#tailings.#Minerals#Engineering,#v23#p1101S1112.#

55.# Freed,#R.,#Marsland,#R.,#Cho,#J.,#McWilliams,#I.,#Henderson,#S.##2012.#Investigating#loadings#from# tailings#and#waste# rock# for#closure#planning#at#Nyrstar#Myra#Falls.# (Invited#Speaker)#19th#Annual#British#Columbia#MEND#Metal#Leaching#and#Acid#Rock#Drainage#Workshop.#Vancouver,#BC,#December.#

56.# Gonzales#V.#2005.#Cobriza’s#Cu#tailings#surface#stacking,#a#successful#story#in#Proceedings#Eighth#International#Seminar#on#Paste#and#Thickened#Tailings,#R.J.#Jewell#and#S.#Barrera#(eds),#Australian#Centre#for#Geomechanics,#Perth,#Australia,#p#261–274.#

57.# Hohne,#J.,#Bedell,#D.,#Fogwell,#G.#2004.#EKAPA#mining#success#story#using#the#DorrSOliver®#Eimco# Deep# Cone# Paste™# Thickener.# International# Seminar# on# Paste# and# Thickened#Tailings.#March#31S#April#2.#

58.# Idaho# DEQ.# 2014.# Pollution# Prevention# Champion.# http://newjerseymining.com/wpScontent/uploads/2017/01/newSjerseySmineSDEQSAward.pdf#(accessed#Jan#2018).#

59.# Lundin# Mining# 2016.# NevesSCorvo# Mine# Summary# Report.#http://www.lundinmining.com/i/pdf/Summary_Report_NevesSCorvo.pdf# (accessed# Dec.#2017)#

60.# Lundin# Mining# 2017.# NevesSCorvo# Zinc# Expansion# Project#http://www.lundinmining.com/i/pdf/2017S05SnevesScorvoScp.pdf#(accessed#Jan.#2018)#

61.# Newman,#P.,#Verburg,#R.,#Fordham,#M.#2004.#Field#Cell#Testing#of#SubSAerial#Paste#Disposal#of# Pyritic# Tailings.# In$Proceedings# of# the# International# Seminar# on# Paste# and# Thickened#Tailings.#Paper##6.#Cape#Town,#South#Africa,#March#31S#April#2.##


!


+

62.# Nyrstar,#2014.#Nyrstar#Myra#Falls#Operation,#Maintenance#and#Surveillance#(OMS)#Manual#for#the#Tailings#Disposal#Facilities#&#Water#Treatment#System.#November.#

63.# Nyrstar,# 2017.# Nyrstar# Myra# Falls# –# Application# to# Amend# Mine’s# Act# Permit# MS26:#Requesting#Surface#Stockpile,#Hauls,#and#Paste#Backfill#–#Revision#1.#Submitted#to#the#BC#Ministry#of#Energy,#Mines,#and#Petroleum#Resources#(EMPR).#October#10.##

64.# Ozdemir,#O.,# Bascetin,#A.,# Adiguzel,# D.,# Tuylu,#S.,# Savas,# E.# 2016.# Study#of# rheological#behavior#of#mineral#processing#tailings#in#surface#paste#technology.#In:#Proceeding#of#SME#Annual#Meeting,#Phoenix#AZ,#USA.#February#21S24.##

65.# Shuttleworth,# J.,# Thomson,# B.,# Wates,# J.# 2005.# Surface# paste# disposal# at# Bulyanhulu—practical# lessons# learned.# In:#Paper#presented#at# the#proceedings#of# the#8th# international#seminar#on#paste#and#thickened#tailings—Paste#2005,#Santiago,#Chili#

66.# Simms,#P.,#Grabinsky,#M.,#Zhan#J.#2005.#Laboratory#evaluation#of#evaporative#drying#from#surface# deposited# tailings# at# the# Bulyanhulu# gold#mine.# In:# Paper# presented# at# the# 58th#Canadian#Geotechnical#Conference,#Saskatoon,#Canada#

67.# Simms,#P.,#Grabinsky,#M.,#Zhan,#G.#2007.#Modelling#evaporation#of#paste#tailings#from#the#Bulyanhulu#mine.#Can#Geotech#J#44(12):1417–1432#

68.# Theron,#M.,#Addis,#P.,#Wates,#J.,#Martin,#V.#2005.#Bulyanhulu#mine#(Tanzania)#paste#tailings#facility:#relating#the#unsaturated#properties#of#gold#tailings#to#rate#of#rise.#In:#Proceedings#of#the#8th#international#seminar#on#paste#and#thickened#tailings—paste#2005,#Santiago,#Chili#

69.# Theriault,#J.,#Frostiak,#J.,#Welch,#D.#2003.#Surface#Disposal#of#Past#Tailings#at#the#Bulyanhulu#Gold#Mine,# Tanzania.# In:# Proc.# 2nd#Mining#and# the#Environment#Conference,#May#25S28,#Sudbury,#Ontario.#

70.# Verburg,# R.,# Oliveira,# M.# 2016.# Surface# paste# disposal# of# highSsulfide# tailings# at# Neves#Corvos#S#evaluation#of#environmental#stability#and#operational#experience.#In:#Drebenstedt,#C.# &#Paul,#M.:# IMWA#2016#–#Mining#Meets#Water# –#Conflicts# and#Solutions.# # p361S367r#Freiberg/Germany#(TU#Bergakademie#Freiberg).#

71.# Williams,#M.,#Seddon,#K.,#Fitton,#T.#2008.#Surface#disposal#of#paste#and#thickened#tailings#–#a# brief# history# and# current# confronting# issues.# Proceedings# of# the# 11th# International#Conference#on#Paste#and#Thickened#Tailings.#Perth,#Australia,#p285S294.#

72.# Wu,#ASX.,#Jiao,#HSZ.,#Wang,#HSJ.,#Yang,#SSK.,#Li,#L.,#Yan,#QSW.,#Liu,#HSJ.#2011.#Status#and#development#trends#of#paste#disposal#technology#with#ultraS#fine#unclassified#tailings#in#China.#In:# Proceedings#of# the# 14th# international# seminar# on# paste#and# thickened# tailings,#Perth,#Australia,#p477S490.#

73.# Yilmaz#E,#Benzaazoua#M,#Bussière#B,#Pouliot#S#(2014b)#Influence#of#disposal#configurations#on#hydrogeological# behaviour#of# sulphidic#paste# tailings:# a# field#experimental# study.# Int# J#Miner#Process#131:12–25#

#

Surface9Placed'Cemented9Paste'Tailings'

74.# Benzaazoua#M,#Perez#P,#Belem#T,# Fall#M.#2004.# A# laboratory# study# of# the# behaviour# of#surface#paste#disposal.#In:#Proceedings#of#the#8th#international#symposium#on#mining#with#backfill,#Beijing,#China,#September#19S21,#p180S192.#

75.# Cincilla,#W.,#Landriault,#D.,#Verburg,#R.#1997.##Application#of#Paste#Technology#to###Surface###Disposal###of###Mineral###Wastes,###in:###Proceedings###of###the###Fourth###International###Conference##


!


+

on##Tailings##and##Mine##Waste##‘97,##Fort##Collins,##Colorado,##13S16##January.#Rotterdam:#A.#A.#Balkema,#p343S356.#

76.# Deschamps,#T.,#Benzaazoua,#M.,#Bussière,#B.,#Aubertin,#M.,#Belem,#T.#2008.#Microstructural#and# geochemical# evolution# of# paste# tailings# in# surface# disposal# conditions.# Mineral#Engineering.#v21#p341S353.#

77.# Deschamps,# T.,# Benzaazoua,# M.,# Bussière,# B.,# Aubertin,# M.# 2011.# Laboratory# study# of#surface#paste#disposal#for#sulfidic#tailings:#Physical#model#testing.#Minerals#Engineering.#v24#p794S806.#

78.# Dinis,#M.L.,#Vila,#M.C.,#Fiuza,#A.,#Futuro,#A.,#Nunes,#C.#2016.#CoSdisposal#of# coal# ash# in#surface# paste# tailings#disposal# practices# –# a#gold#mining# case# study.#World#Academy#of#Science,#Engineering#and#Technology,#International#Science#Index#115,#International#Journal#of#Environmental,#Chemical,#Ecological,#Geological#and#Geophysical#Engineering.#v10#p754S760.#

79.# Ichrak,# H.,# Benzaazoua,# M.,# Maqsoud,# A.,# Bussière,# B.# 2016.# Effect# of# cementitious#amendment#on# the# hydrogeological# behavior# of# a# surface# paste# tailings’# disposal.# Innov.#Infrastruct.#Solut.#p1S19.#

80.# Liu,#Q.,# Liu,#D.,# Liu,#X.,#Gao,#F.,#Li,#S.#2016.#Research#and#application#of# surface#paste#disposal# for# claySsized# tailings# in# tropical# rainy# climate.# International# Journal# of# Mineral#Processing.#v157#p227S235.#

81.# Seipel#K.,#Sheumaker,#D.,#and#Kirk,#L.#2017.!Kinetic#Tests#of#NonSAmended#and#Cemented#Paste#Tailings#Weathering#in#Subaqueous#and#Subaerial#Settings.#–#In:#Wolkersdorfer,#C.r#Sartz,# L.r# Sillanpää,# M.# &# Häkkinen,# A.:# Mine#Water# &# Circular# Economy# vII# p830S836r#Lappeenranta,#Finland#(Lappeenranta#University#of#Technology).#

82.# Verburg,#R.#2001.#Use#of# paste# technology# for# tailings#disposal:# #potential# environmental#benefits#and# requirements# for#geochemical#characterization.# In#Proceeding#for# the,# IMWA#Symposium#Belo#Horizonte.#

#

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