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Carbondioxide(CO
2
)isabsorbedby land andvegetationthroughtheprocessofphotosynthesis.The
netemissionsarenegative(sequestration)andsubstantial,offsettingapproximately884MMTCO
2
E,or
approximately13%oftotalemissionsin2006.
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Thecarbonsequestrationandstorageprovidedby
land canbepreservedthoughsustainable land management practices,andcanbeenhancedby
restorationof land, suchasreforestationofcontaminated land.
Theemissionsestimateforthe land basedcarbonsinkisgivenbytheInventory.Specifically,Chapter7,
Land Use, Land UseChange,andForestry,providesanassessmentofthenetGHGfluxresultingfrom
theusesandchangesin land typesandforestsintheU.S.,includingnetemissionsfromforestland
remainingforestland,croplandremainingcropland, land convertedtocropland,grasslandremaining
grassland, land convertedtograssland,settlementsremainingsettlements,landfillyardtrimmings,and
... September2009
vehiclemilestraveledincreasedby42%,whichagainishigherthantherateofpopulationgrowthand
duelargelytotheincreaseindeveloped land.
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Despiteimprovementsmadeinvehiclefuelefficiency
sincethe1970s,GHGemissionsfromthetransportationsectorhaveincreasedinrecentyears,inpart
duetotheincreaseintotalvehicle‐milestraveled.
71
Smartgrowthapproaches—suchasreuseofproperty;infill,compact,andmixed‐usedevelopment;
andthecleanupandredevelopmentofcontaminatedproperty—reducedevelopmentpressureon
greenfields.Compact,mixed‐usedevelopmentmakesiteasierforresidentstowalk,bike,taketransit,
ordriveshorterdistances,whichhelpsreducevehicle‐milestraveledandhencetheGHGemissions
associatedwithlocaltravel.Inaddition,moresustainable land useanddevelopmentatthelocaland
statelevelsthatprioritizesenergyefficiency,reducedenergyconsumption,andreducedmaterial
consumptioninbuildingandinfrastructureconstructioncanfurtherreduceGHGemissions.
Land revitalizationpracticespromotethecleanupandreuseofcontaminated land. Byconsideringthe
impactof land management throughoutitslifecycle,theUnitedStatescanrealizesignificant
reductionsinGHGemissions.Decisionsatthelocal,state,orfederallevelrelatedtothecleanup,
restorationand/orreuseofcontaminated land (i.e., land revitalization)canalsoreduceGHGemissions.
OSWER’srolein land management isfocusedonpreventing land frombecomingcontaminatedandon
thecleanupandreuseof land thathasbeencontaminated.Throughtheseprograms,EPAcurrently
tracksmorethan488,000contaminatedorpotentiallycontaminatedsitescoveringalmost15million
acresacrossthecountry.
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ManyofthesesitesrequiresometypeofcleanupinvolvingEPAand/orits
federal,state,tribal,andlocalpartnersbeforethepropertycanbereused.Todate,EPAhashelped
makemorethan917,000acresofpreviouslycontaminated land readyforreuse.
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However,itshould
benotedthatEPAdoesnotdeterminethenewuseofEPA‐trackedsites;reusedecisionsfor
contaminated land, includingEPA‐trackedcontaminated land, aremadebyindividualpropertyowners
andinaccordancewithlocalandstate,tribal,andfederal land useregulationsandanyrequirementsof
theapplicablecleanupprogram.
EPAandotherorganizationsinvolvedwithcleaningupcontaminated land mayfindopportunitiesto
employcleanuptechniquesthatprovideanequivalentlevelofenvironmentalandhumanhealth
protectionwhileemittingloweramountsofGHGsthrough:1)optimizingremediesandtreatment
systems bothfornewandexistingremedies;2)usingalternativeenergyderivedfromcleanerand
renewableenergysources;and3)accountingforthetechnicalneedsofpotentialreuseoptionsand
incorporatingthemthroughoutthecleanupprocessestofacilitatesustainablereuseoftheproperty
andpreservationofgreenfields.
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Sequesteringcarbononthesesitesisanotherpotentialbenefitfromsomecleanupandreuse
activities—particularlyonformerminelands.Atsomesites,organicsoilamendmentscanbeusedto
remediatethesite,boostingtheamountofcarbonsequesteredinthesoilandenhancingvegetation
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REDUCINGORAVOIDINGGHGEMISSIONSTHROUGH LAND MANAGEMENT PRACTICES
Land management describeshowwemanageanduse land toprovideopenspaceandhabitat,food,
naturalresources,andplacesforpeopletolive,work,andrecreate.EPApromotesintegrated land
management strategiesthatuse land asproductivelyandsustainablyaspossiblebypromotingsmart
growth,preventingandminimizingtheoccurrenceofcontaminationandbycleaningup,reusing,and
restoringcontaminated land forbeneficialreusebycommunities.
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AsdescribedinBox7, land management hasthreekeycomponents: land protection,sustainable land
use,and land revitalization.Similartothematerials management approachesthatcanbeusedinthe
materialflow, land management approachescanbeusedtoreduceGHGemissionsbyimproving
practiceswithinoracrosseachofthesecomponents. Land protectionpracticeslimithowmuch land is
contaminatedeachyear.When land iscontaminated,itshouldbe
cleaneduptolevelsprotectiveofhumanhealthandthe
environment.
Land...