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Section 2 Spring 2013 Environmental Practicum AuthorsBrian Crawford, Lauren Heidingsfelder, Ross Pringle, Greg Skupien, and Sam Woolford
Contributing ResearchersCatherine Bartenstein, Ian Calhoun, Clement Cullens, and Amble Johnson
River Basin Center | Odum School of Ecology | The University of Georgia
SewaneeUtilityDistrictConstructedWetlandsPilotProject:
Integratingecological,financial,andsocialfactorsintocommunitydecisions
Section 2 Spring 2013 Environmental Practicum Authors
BrianCrawford
LaurenHeidingsfelder
RossPringle
GregSkupien
SamWoolford
ContributingResearchers
CatherineBartenstein
IanCalhoun
ClementCullens
AmbleJohnson
EnvironmentalPracticum‐Spring2013
RiverBasinCenter
OdumSchoolofEcology|UniversityofGeorgia
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ExecutiveSummaryDuringSpringof2013,we(EnvironmentalPracticumstudentsattheUniversityofGeorgia)conductedamulti‐partprojecttoaidinthedevelopmentofapotentialwastewatertreatmentwetlandinSewanee,TN.TheSewaneeUtilityDistrict(SUD)currentlytreatsallwastewaterinthecommunityusingaLandApplicationSystem,andin2011‐2012engagedPracticumstudentstodeterminethefeasibility,designconsiderations,andcostsassociatedwithapilotprogramtoinvestigatethepossibilityoftransitioningtoaconstructedwetlandtreatmentsystem.Wehavecontinuedthiseffortbycompilingarecommendedmonitoringprogramforthepilottreatmentwetland,creatingeducationalandpublicrelationsmaterialtobeusedtodisseminateinformationaboutthewetlandproject,anddetailingopportunitiesforextractingrevenuefromtheproposedconstructedwetland.Inthisreportweoutlinemonitoringrecommendationsthatfallintothreecategories,or‘tiers,’allofwhicharerelevanttothreemonitoringgoals:1.Describeandevaluatewetlandtreatmenteffectivenessandoperation;2.Collectdataandinformationtoplanforandimprovefuturewetlandandwastewatermanagement;3.Identifycost‐effectiveopportunitiesforadvancementandcommunitypartnerships.Thefirsttierconsistsofwaterqualityandoperationalmonitoringthatweconsiderimmediatelynecessarywiththeimplementationofthewetland,duetoitsrelevancytothepermittingofapotentialexpansionofthepilotproject.Secondtiermonitoringpracticesarethoseweviewasnotimmediatelynecessary,butrelevanttowetlandfunction,suchasmonitoringofadditionalwatercharacteristics,performingadditionalsampling,andmonitoringfaunaandflora.Thirdtiermonitoringpracticesdetailpossibilitiesformonitoringpartnershipswiththirdparties,andopportunitiesforadaptivemanagementandexperimentation.Inadditiontoestablishingrecommendedmonitoringprotocols,wecreatedtwofilms,spurredbyrequestsfromtheSewaneeUtilityDistrictandtheSouthernAssociationofCollegesandSchools(SACS),tocommunicatethestatusandbenefitsofthepilotprojecttothegreaterSewaneecommunityandtoacademia.Onefilmfocusedoneducatingthegeneralpublicandotherutilitydistrictsinterestedinusingthistechnologyaboutthedesign,function,andbenefitsassociatedwithconstructedwetlandswhilealsoacknowledgingandaddressinglocalconcernsregardingthisproject.Dovetailingfromthiseffort,asecondfilmwascreatedtohighlightthecollaborationbetweentheUniversityofGeorgia,UniversityoftheSouth(Sewanee),SewaneeUtilityDistrict,andClaytonCountyWaterAuthoritythatinvolvedacademics,municipalemployees,graduates,andundergraduatestudents.
Finally,weexploredoptionsforgeneratingincomefromtheconstructedwetlandstoleveragetheproductivityandservicesthatthewetlandsalreadyprovide.Thefiveoptionsinclude
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convertingbiomassharvestedfromthewetlandtocompost,fuelpellets,biogasorcellulosicethanol,aswellassellingcarboncreditsinacarbonoffsetmarket.Ofthesefiveoptions,twostoodoutasthemostfeasiblepossibilitiesforneartermimplementation:compostandfuelpellets.Athird,biogas,isalsofeasiblebutrequiresmoreofaninitialinvestment.Thelasttwo,cellulosicethanolandsellingcarboncredits,posemorechallengesduetotechnologicalconstraintsandmarketuncertainty.However,rapidlyadvancingtechnologies,changingmarketsandnewlaworregulationsmaymakethelasttwooptionsmoreviableinthemediumterm.Anyoftheseoptionsseempreferabletosimplyburningthebiomass,whichisthewaythatmanyconstructedwetlandsarecurrentlymaintained.Itisimportanttonotethatremovalofthebiomass,whetherthroughburningorharvest,isnecessarytomaintainthefunctionofthewetlands.Otherwisetheplantsbecometoodense,flowisrestrictedandtheservicesofwastewatertreatmentaregreatlyreduced.
Acknowledgements
WewouldliketothanktwomembersoftheSewaneecommunitythatwereintegraltotheinitiationanddevelopmentofthisproject:BenBeavers,GeneralManageroftheSewaneeUtilityDistrict,forhisinterestinusingthistechnologyandallowingustheopportunitytoassistinachievinghisgoals;andProfessorDeborahMcGrath,AssociateProfessor&ChairofBiologyatTheUniversityoftheSouthinSewanee,TN,andtheundergraduatestudentsoftheHumanHealthandtheEnvironment(Biology232)classfortheircollaborationandresearchonthisproject.
Wewouldalsoliketothankthefollowingcollaborators:DonnieKiblinger,Supervisor,NaturalTreatmentSystem,ClaytonCountyWaterAuthority,forhostingusduringtripstotheClaytonCountywetlands;RobertO’Dette,AssistantManagerforMunicipalFacilitiesandStateBiosolidsCoordinator,DivisionofWaterPollutionControl,TennesseeDepartmentofEnvironmentandConservation,forprovidingexpertiseandmaterialsrelatedtotheTennesseeNPDESpermittingprocess;ProfessorLaurieFowlerforcoordinatingandsupportingtheentirebreadthofthisproject;ProfessorsMartinKnoll(Sewanee)andRonCarroll(UniversityofGeorgia)forlendingtheirtimeandexpertisetoresearchingandcommunicatingourproject;andAmbleJohnsonfortechnicalsupport,manyhoursofediting,andartisticsupervisioninthemakingofthefilms.
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TableofContentsExecutive Summary ......................................................................................................................................ii
Acknowledgements .....................................................................................................................................iii
1. Monitoring recommendations for pilot constructed treatment wetland................................................1
1.1. Current treatment system and monitoring.….................................................................................1
1.2. Scope of potential future monitoring..............................................................................................2
1.3. Tier 1 monitoring plan.....................................................................................................................3
1.3.1. Monitoring of construction practices....................................................................................3
1.3.2. Monitoring wetland maintenance and operation.................................................................4
1.3.3. Monitoring for water treatment effectiveness......................................................................5
1.3.4. UV vs. chlorine sterilization………...........................................................................................6
1.4. Tier 2 monitoring.............................................................................................................................7
1.4.1. Micro‐constituents.................................................................................................................7
1.4.2. Bacterial source.....................................................................................................................8
1.4.3. Additional sampling locations................................................................................................8
1.4.4. Fauna and Flora...................................................................................................................10
1.5. Tier 3 monitoring...........................................................................................................................11
1.5.1. Research partnerships.........................................................................................................11
1.5.2. Citizen science and public engagement...............................................................................11
1.5.3. Adaptive management and experimentation......................................................................12
2. Communications.....................................................................................................................................13
2.1. Constructed wetland education video………….....………………..................……...…............................14
2.2. Collaboration video.......................................................................................................................15
3. Possible income sources from a constructed wetland...........................................................................15
3.1. Biomass to compost......................................................................................................................17
3.2. Biomass to fuel pellets..................................................................................................................17
3.3. Biomass to biogas..........................................................................................................................18
3.4. Biomass to cellulosic ethanol........................................................................................................18
3.5. Carbon offset credits.....................................................................................................................19
3.6. Final Assessment of Income Source Options……………………………..................................................20
Appendix A: Required materials and costs for water quality monitoring...................................................22
Appendix B: Sewanee Utility District State Operating Permit....................................................................26
Appendix C: NPDES permit issued to existing constructed wetland in Lavonia, Georgia...........................38
Appendix D: NPDES permit issued to Winchester, TN wastewater treatment facility...............................55
Appendix E: Constructed wetlands permitting in Georgia and Tennessee...............................................124
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Appendix F: NPDES permit issued to Fall Creek Falls State Park wastewater treatment wetland...........128
Appendix G: Interview questions..............................................................................................................153
Appendix H: Movie treatments................................................................................................................156
Appendix I: Future marketing considerations: water reclamation case studies.......................................159
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1.MonitoringRecommendationsforPilotConstructedTreatmentWetland TheSewaneeUtilityDistrict(SUD)provideswastewatertreatmentfortheSewanee,TNcommunityinFranklinandMarionCounties,Tennessee.ThecurrentmethodoftreatmentisaLandApplicationSystem(LAS):wastewaterfromatleast678connectedfacilitiesiscollected,treatedinaseriesofthreelagoons,andsubsequentlydischargedbysprayirrigationtonearbylandplots.Thisprocessusesnaturalphysicalandbiologicalprocessesinthelagoonsandonthelandtoeffectivelytreatwastewater,butisspace‐andenergy‐intensive,anddoesnotallowfordirectreclamationoftreatedwater.SUDisinterestedinthepotentialofalteringtheirtreatmentpracticestoincludeaconstructedwetland,andeventuallytoswitchawayfromtheLAStoaconstructedwetlandtreatmentsystem,inordertomaximizeefficiencyinthetreatmentprocessandpotentiallyactaswaterstorageduringdroughtconditions.
TotestthefeasibilityofthistypeofsysteminSewanee,SUDhasproposedapilotwetlandthatwouldbeanadditiontotheircurrentsystem.Wastewaterfromthefirstexistinglagoonwouldflowthroughatwo‐cellconstructedwetland,beforeenteringthesecondlagoonandeventuallybeingappliedtothesprayfields.TheultimategoalofthepilotprojectistounderstandthepotentialforusingconstructedwetlandstotreatSUDwastewater.Tothisend,monitoringofthewetland’streatmentperformancewillbenecessaryforfuturedesignandmanagementofalargersystem,aswellastoobtainrequiredpermitsfromtheTennesseeDepartmentofEnvironmentandConservation(TDEC).Thisreportoutlinesthetype,method,andcostofpotentialfuturemonitoringpracticesthatcouldbeundertakenwiththeconstructionofthepilotwetland,andisorganizedin‘tiers’relatingtothenecessityandimmediacyrelativetothegoalsoftheproject. 1.1.CurrentTreatmentSystemandMonitoring BecausethecurrentLASdoesnotdischargewastewatertowatersoftheUnitedStates,butrathertothelandsurface,apermitisnotrequiredthroughtheNationalPollutionDischargeEliminationSystemprovisionofsection402oftheCleanWaterAct(33U.S.C.§1342).ThestateofTennesseerequiresallwastewatertreatmentfacilitiestobeapprovedandpermittedbyTDEC(T.C.A.§69‐3‐108),soSUDcurrentlyholdsaStateOperatingPermit(AppendixB)whichdictatescurrentmonitoringrequirementsfortheLAS.Thepermitrequirescontinuousflowmonitoringofboththeeffluenttothesprayirrigationplotsandinthreeconveyancesthataretheprincipaldrainsofthesprayfields.TheseflowsarereportedmonthlytoTDECasaveragedailyflows.SUDmustalsotakemonthlygrabsamplesfromtheeffluenttotestandreportBiologicalOxygenDemand(BOD),Nitratelevel,andE.coliconcentrations.Currentlythesesamplesaresenttoastateapprovedlaboratoryfortesting.Themaximumallowable
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levelsoftheseparametersplacenooperationalconstraintsontheLAS,althoughSUDmustacknowledgeandreportnon‐compliance.
Theprimarypermittedparametersthatgovernthesystemoperationareoverlandflowandpondinginthesprayfields.Ifwastewaterappliedtothelandpoolsintosurfacefeaturesthatcouldpotentially‘dischargetoanysurfaceorsubsurfacestream,’operationisprohibited.SUDmustkeeprecordstoshowpondinghasnotoccurred,orthatitisaresultofnaturaloccurrencesratherthantreatmentsystemoperation.Aspartofthis,SUDmustalsomonitorandreportprecipitationonsite.Morethan15yearsago,apreviousversionoftheOperatingPermitrequiredmuchmorecomprehensiveandfrequentwaterqualitytesting,soalaboratoryexistsatthewastewatertreatmentsitethatwasusedtomonitorwaterquality(includingBOD,nutrientlevels,andsuspendedsolids).Thelaboratoryhasbeenindisusesincethechangeinpermitrequirements.
1.2.Scopeofpotentialfuturemonitoring TheadditionofaconstructedwetlandtothecurrentLASwillnotchangethepermitrequirementsorSUD’scurrentmonitoringrequirements.Weproposeadditionalmonitoringinthepilotconstructedwetlandforanumberofreasons.TheprimarypurposeofthepilotistodeterminetheeffectivenessofusingatreatmentwetlandtotreatSUDwastewater.Inordertomeasureperformance,itwillbenecessarytomonitorthepotentialpollutantsthatareassociatedwithmunicipalwastewaterquality.Ifthepilotweretobescaledupandusedastheprincipaltreatmentmethod,waterwouldultimatelybedischargedintoasurfacepond,meaningSUDwouldneedtoobtainanNPDESpermitfromTDEC.IncompliancewiththeCleanWaterAct,thispermitwillrequiremonitoringformoreparametersandhavestricterlimitsforeffluentwaterquality.Inthisreport,thistypeofmonitoringisincludedinTier1,asweconsideritnecessarytoevaluatethefeasibilityofmovingforwardwiththefull‐scalewetlandtreatmentsystem.
ThesetreatmentwetlandswouldbeonlythesecondoftheirkindinTennessee,soTDEChaslimitedexperienceoverseeingandapprovingconstructedwetlandsforwastewatertreatment.Becauseofthis,monitoringofthewetlandpilotshouldalsoincludecharacteristicsthatwillprovideassurancesthattreatmentwetlandsareviablewastewatertreatmentsystemsingeneral.Recordingaspectsofconstruction,maintenance,operatingprocedure,andmanagementwillaidinfacilitatingthepermittingprocessandallowTDECtoevaluatethetreatmentperformancepotentialofwetlandsmorecomprehensively.WeconsidermonitoringofmanagementpracticesthataffectpermittedrequirementstobeTier1monitoring,whilerecordingotherwetlandoperationalfeaturesmaybelessimmediatelynecessary(Tiers2or3).
Beyondthesereasonsformonitoring,thereareopportunitiesforadditionalmonitoringpracticesthatwilllikelynotberequiredbyafuturepermit.Dependingonfunding,personnel,
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andinterest,monitoringofadditionalwaterqualityparameterscouldplaceSUDattheforefrontofthewastewatertreatmentfield,andasaleaderinunderstandingthebestpracticesfortreatmentwetlandoperation.TherearealsoopportunitiestopartnerwiththeUniversityoftheSouthandtheSewaneecommunityforeducation,research,citizenscience,andpublicengagement,andthesepartnershipsmaygeneratefundingforadditionalmonitoringandmakeSUDaleaderandexampleforothercommunities.WeconsidertheseadditionalmonitoringpracticesandpartnershipsinTiers2and3.
1.3.Tier1monitoringplan Webelievethetypeandfrequencyofmonitoringthatwesuggestin‘Tier1’isthemostimmediatelysensibleandpracticalsuiteofpracticestoimplement,basedonthegoalsfortheconstructedwetlandpilotproject.Todeterminewhichtypesofmonitoringthatbelonginthistier,weexaminedmultipleexistingNPDESpermitsforconstructedtreatmentwetlandsinthestateofGeorgia(AppendixC),existingNPDESpermitsforwastewatertreatmentfacilitiesinthesamewatershedasSUD(UpperElkRiver)(AppendixD),thecurrentSUDStateOperatingPermitfortheLAS,andthetemplateusedbyTDECforissuinganyNPDESpermit.WealsospokewithBenBeavers,SewaneeUtilityDistrictGeneralManager,andRobertO’Dette,AssistantManagerforMunicipalFacilitiesandStateBiosolidsCoordinator,DivisionofWaterPollutionControl,TennesseeDepartmentofEnvironmentandConservation.TheseconversationsclarifiedSUD’scurrentandfuturemonitoringcapabilities,aswellasthefutureprocessforobtainingaNPDESpermitforawetlandtreatmentsysteminSewanee.Finally,wereviewedtheEnvironmentalProtectionAgency(EPA)guidelinesfortestproceduresfortheanalysisofpollutants(40C.F.R.§136)inordertodeterminemonitoringmethodologyandcostsforthepracticesbelow.
BelowweseparateTier1monitoringpracticesintothreecategoriesbasedontypeandtiming:ConstructionPractices,MaintenanceandOperation,andWaterTreatmentEffectiveness.Generaljustificationforthetypeofmonitoringsuggested,aswellassuggestedfrequencyandmonitoringlocation,isincludedbelow.ActualmonitoringproceduresandcostscanbefoundinAppendixAattheendofthisdocument.
1.3.1.Monitoringofconstructionpractices Asstatedabove,thesewillbeonlythesecondwetlandsconstructedformunicipalwastewatertreatmentinthestateofTennessee.TheultimategoalofthispilotprojectistotesttheeffectivenessofusingconstructedwetlandsforthispurposeinSUD,withtheobjectivetodeterminethefeasibilityofmovingawayfromthecurrentsystemandtodischargetosurfacewater.Intheeventitelectstoproceed,SUDwilleventuallyneedtoprovideTDECwithcomprehensiveinformationaboutthepilotwetlandsinordertoobtainanNPDESpermit.
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BasedoninformationfromourresearchandcommunicationswithTDEC,webelievethemoreinformationavailableregardingtheconstruction,management,andmaintenanceofthewetlands,theeasierthefuturepermittingprocesswillbe.Assuch,werecommendthataccuraterecordsbemaintainedandpreservedthatpertaintothedesignandconstructionofthepilotwetlands.
WesuggestthatSUDrequiretheengineering,construction,andcontractingfirmsthatcarryouttheworkofdesigningandbuildingthewetlandswillkeeprecordssuchasdrawingsandblueprints,plantingcharts,designofmechanicalfeaturessuchasweirsandvalves,constructionmaterialsused,constructionschedule,andactionstaken,amongothers.SUDshouldobtainacopyoftheserecordsEspeciallyimportantrecordswillbedimensionsofallwetlandproperties,designandoperationofmechanicalelements,recordsoftheexcavationprocess,quantitiesofanymaterialsaddedforliningcellsorestablishingplantcover,andplantinglistsandlocations.
WealsorecommendthatSUDrequestthecontractedfirmstomaintainanaccuratedailyconstructionlogtoincludeconstructionprogressandactions,andespeciallyanydeviationsfromoriginalconstructionplans.Itisunlikelythatallaspectsoftheconstructionprocesswillconformexactlytopaperspecifications,andrecordingthesedeviationswillnotonlybehelpfulforthefuturepermittingprocess,butalsoforongoingoperationandmaintenanceofthewetlands.WedonotanticipatemonitoringduringconstructiontobeofanyadditionalcosttoSUD,asitwillbecarriedoutbythethirdpartiescontractedtodesignandbuildthewetlands.Weincludethesemonitoringpracticeshereonlytostresstheirimportance,aswellastorecommendthatSUDrequireanyfirmithirestomonitortheconstructionprocessextensivelyandtoprovideSUDwithcopiesoftheserecords.
1.3.2.Monitoringwetlandmaintenanceandoperation Monitoringofmaintenanceandoperationactivitiesintheconstructedwetlandwillbeimportantformanyofthesamereasonsasrecordingtheconstructionprocess.BecauseofthenoveltyofusingconstructedwetlandsforwastewatertreatmentinTennessee,providingTDECPollutionControlDivisionwithcomprehensiveinformationregardingtheoperationofaworkingwetlandwillaidinthefuturepermittingprocess.Asanadditionalbenefit,monitoringofthissortcouldserveasanexamplebywhichotherconstructedwetlandsinTennesseearepermittedandmanaged,aswellasinformfutureadaptivemanagementoftheSUDwetlands.
ContinuousmonitoringofwaterflowdischargedfromthewetlandswillberequiredinanyfutureNPDESpermit,butitisunclearwhetheradditionalflowmonitoringofwaterleavingthepilotwetlandswouldprovideadditionalinformationatthistime.Thiswilldependontheresidencetimeofwaterinthereceivinglagoonbeforebeingdischargedtothesprayfields.Ifthereislikelytobeasignificantdifferencebetweenflowleavingthewetlandsandeffluentto
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thesprayirrigationplots,werecommendthatdailycontinuousflowbemonitoredaswaterisdischargedtothereceivinglagoon.Thisflowestimatewillbeimportanttoinferwaterresidencetimeinthetreatmentwetlandsinordertogaugetreatmenteffectivenessrelativetothedurationofresidenceinthecells.ThisinformationwillhelpinformanyfutureexpansionofthewetlandstobesuitableforallofSUD’swastewatertreatmentresponsibilities.
Maintenanceandoperationofthewetlandisnotexpectedtobeoverlyextensiveorcost‐prohibitive,andallactivitiesundertakentomanagethehealthandfunctionofthewetlandsshouldberecordedanddated,alongwithadescriptionandduration,ifapplicable.Day‐to‐daymaintenanceactionsthatshouldberecordedinamaintenancelogformatincludeadjustmentofflow‐orwater‐level‐controlweirsduetoweatherevents,anymaintenanceofvalves,pipes,andconveyances,repairandmowingofberms,andmaintenanceofanycontinuousmonitoringtechnology.Lessfrequentactivitiesthatshouldalsobeloggedmayincludeanyre‐plantingorwetlandvegetationmanagementrequired,vegetationremoval(eitherthroughharvestorburning),drydownofoneorbothcellsfordredgingorinspection,wildlifeandpestcontrolactions,aswellasanyotheractivitiesbyoperatorstomaintainwetlandperformance.
WerealizetheserecommendationsmayaddsomeadditionaltimeandefforttothetaskofoperatingtheSUDwastewatertreatmentfacility,butbelievethattheyarejustifiedbythebenefitsprovided:communicationofcomprehensiveinformationregardingtheoperationofatreatmentwetlandtoTDECwillfacilitatefuturepermitting;thoroughrecord‐keepingofmaintenanceactivitieswillbehelpfulindiagnosinganyfutureproblemsthatariseandadaptingwetlandmanagementtomoreeffectivelytreatwastewater;andSUDoperationalexperiencecouldserveasaresourceforothercommunitiesstatewidethatplantouseconstructedwetlandsforwastewatertreatment.
1.3.3.MonitoringforWaterTreatmentEffectiveness Tomonitorforwatertreatmenteffectiveness,SUDmustutilizeTier1datacollectedfrombothinfluentandeffluent.WhilethecurrentTDECpermitmonitorsflow,biologicaloxygendemand(BOD),nitrateandE.coli,additionalmonitoringparameters,including:totalsuspendedsolids(TSS),totalnitrogen,dissolvedoxygen(DO),totalphosphorus,settleablesolids,pH,andtotalammoniaasnitrogen,willallowforcomparisontootherNPDESpermitholdingfacilities,suchasWinchester,TNSewageTreatmentPlant(WSTP).Bymonitoringtheparametersbeyondthecurrentpermit,SUDcandevelopanalogousdatacontainingBODandTSS%removal,aswellmg/Lofvariouscomponentsusefulincomparativeanalysis.Withthisdataset,effectivenessandefficiencyoftheCWcomparedtoastandardwastewatertreatmentfacilitycanbequantitativelymeasured.
Forexample,theneighboringcommunityofWinchesteroperatesatraditionalwastewatertreatmentfacility,utilizinganoxidationditchfollowedbyclarification,UVdisinfection,andstairstepaerationprocess(AppendixD).BothSewaneeandWinchesterliewithintheUpper‐
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Elkwatershed.WSTPdischargesdirectlyintotheTimsFordReservoir,neartheconfluenceofElkRiverandBoilingForkCreek(AppendixD).Similarly,SUD’ssprayfieldsarelocatedadjacenttotheopposingendofBoilingForkCreek‐apotentialsurfacewaterdischargesiteforSUD.WiththesecorrespondinghydrologicallocationswefindWSTPareasonablesiteforcomparison.Datafromthiscomparisonwillpresumablyrevealthatconstructedwetlandsareas,ifnotmore,effectiveindecontaminatingwastewaterthanstandardwastewatertreatmentfacilities.
WefurthersuggestconductingaretrospectivestudyonthedatacollectedunderthepreviousSUDOperatingPermitasmentionedinSection1.1:CurrentTreatmentSystemandMonitoring,aswellastheflow,BOD,nitrate,andE.colidatacollectedunderthecurrentSUDpermit.ThesetypesofcomparisonsareusefulindeterminingtheefficiencyoftheCWcellswithinthesystemitself.ThisdatacanbeusedtoillustratethatwaterenteringthesprayfieldsfromtheCWsystemis“cleaner”thanthewaterappliedwithouttheCWcomponent.ThusenforcingtheargumentthatCWaresufficientincleaningwastewaterwithouthavingtobuildandmaintainatraditionalwastewatertreatmentfacilityorcontinuingwiththeuseoftheLAS.Inturnthiscomparisondatawillalsobehelpfulinup‐scalingthepilotCWcellstoafullCWfacility.
UnderthecurrentSUDpermititismorecost‐efficienttosendmonthlysamplesoutforlaboratorytesting.Howeverwithourproposedmonitoringschemeutilizationoftheon‐sitelaboratorymayprovetobethemorecost‐savingmethodofdataanalysis.Withtheassumptionthattheon‐sitelaboratoryisalreadyequippedwithstandardlaboratorysupplies,suchas:glassware,pipettes,hotplate,autoclave,etc.(seeAppendixA,Table3,forcompletelist),updatingthelabwithafewkeyanalyticalinstrumentsandchemicalsuppliesmaybeadvantageousinthelongrun.Table1ofAppendixAliststheabovementionedcommonNDPESrequiredtestingparameters,alongwiththeEPAapprovedmethodoftesting,equipmentandreagentsneeded.AppendixA,Table2comparesestimatedcostsofonsitetestingtotestingperformedatthecommerciallabcurrentlyusedbySUD,ESCLabSciences. 1.3.4.UVvs.Chlorinesterilization SUDwilllikelyhavetochooseafuturedisinfectantmethodtodestroyorinactivatepathogenicviruses,bacteria,andotherorganismsifandwhenthetreatmentwetlandisregulatedbyanNPDESpermit.Chlorinationisthepracticeofmixingachlorinechemicalcompoundwitheffluentinordertokilllivingorganismspresentbyoxidizingcellularmaterial,andsubsequentde‐chlorinationofthewaterwithachemicalagentsuchassulfurdioxidetobindtoandneutralizeactivechlorine.Ultraviolet(UV)sterilizationinvolvesdirectingeffluentnearaUVlightarray,whichhastheeffectofsterilizingbacteriapresentinthewastewaterbydenaturingthegeneticmaterial(DNA)sotheycannotreproduce.ThecapitalcostsofpurchasingandinstallingaUVsystemareontheorderof10%morethanachlorinationsystem,butlongterm
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product(electricityvs.chemicals),operationandmaintenancecostscanbalanceoutthisexpense,particularlyduetothecorrosivenessofchlorinechemicals.1
Despitetheup‐frontcostdisparity,manywastewatertreatmentfacilitiesandtreatmentwetlandsemploytheUVmethod,andwerecommendSUDdoesthesameifandwhendisinfectionisrequiredforanNPDESpermit.TheadvantagesofaUVsysteminclude:avoidanceofhandlingandtransportinghazardouschemicals;inactivationofnearlyallpathogenicviruses,spores,bacteria,andprotozoa;aUVsystemoccupiesmuchlessspacethanachlorinationsystem;therearenopotentiallyharmfuleffectstohumansandwildlifethatcomeincontactwiththewater(chlorinelevelsmustbeadjustedandmonitoredforthisreason);thereisnoneedtomonitorandberesponsibleforresidualchlorinelevelsineffluent,asnoneisintroduced.Whichevermethodischosen,SUDshouldworkcloselywithTDECbeforepurchasingandinstallingasystemtoassurethatthetypeandprocedureisapprovedforpermitting.
1.4Tier2monitoring Thesecondtierofmonitoringsuggestionsprovidesanoverviewofmonitoringpracticesintheconstructedwetlandsthatweviewasnotimmediatelynecessary,butrelevanttowetlandfunctionorthefieldofwastewatertreatment.ByimplementingsomeorallofthesepracticesSUDwouldbecomealeaderininnovativewatertreatmentpractices,andpotentiallyservethefunctionofaworkingresearchstationbycollectinginformationusefultoimprovingwatertreatmenteffectiveness.Thesebenefitswillneedtobeweighedagainsttheadditionalmonetaryandpersonnelcostsimposed.1.4.1Micro‐constituents Withnewinterestandemergingtechnology,examinationofthepresenceandeffectsofpharmaceuticaldrugsinwatersourceshasbecomeanincreasinglypopularfieldofstudy.Bothhumanandenvironmentaltoxicologistsareexploringtopicssuchas:hermaphroditicaquaticwildlife,thesynergisticeffectsofmultipletrace‐levelpharmaceuticalsontheecosystemandhumanhealth,therateofdegradationforpharmaceuticalsindifferentaquatichabitats,etc.Recently,theUnitedStatesGeologicalSurvey(USGS)developedanewmethodformeasuringpharmaceuticalsinvaryingwatersources.Theyuseasolid‐phasemethodofextraction,thenanalyzethecompoundsthroughhigh‐performanceliquidchromatography‐electrosprayionizationmassspectrometry(HPLC‐ESI‐MS)todetectconcentrationsatthemicrogramlevels.2 Commonnamesandclassesofpharmaceuticalsbeingtestedinclude:caffeine,anti‐depressants,hormones‐includingbirthcontrolandmaleenhancementdrugs,antibiotics,andpainmedications.Mostpharmaceuticalsaredetectedandresultsarelistedundertheirchemical
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structurename.Inadditiontopharmaceuticals,heavymetals,PolychlorinatedBiphenyls(PCBs),endocrinedisruptors,pesticides,fertilizersandillicitdrugsarealsoareasofinterest.However,researchintotheeffectivenessofconstructedwetlandsatnaturallyremovingpharmaceuticalsandothercontaminantsisstillnotwidespread.ThusanynewCWsiteusedtotreatdomesticwastewaterofferspotentialforinvestigators,andultimatelygrantfunding.Duetotheeventualpossibilityofrecyclingwastewaterthroughascaled‐upconstructedwetlandintoadrinkingwaterreservoir,webelievethelevelmicro‐constituentremovalinthepilotwetlandisimportantinformationtomonitor.Thereisawarenessofandsupportforthiskindoftestingintheuniversitycommunity,andbecauseoftheprohibitiveequipmentcosts,partnershipwiththeUniversityoftheSouthoranotherschoolmaybetheonlywaytoaccomplishmonitoringofthiskind.Inadditiontoprovidingusefulinformationtofutureplanning,micro‐constituentmonitoringwouldlikelybringbroadsupportforthepilotprojectfromthecommunity,increaseperceivedtransparency,andpotentiallybringfundingandothercollaborativeopportunitiestoSUD.
1.4.2Bacterialsource Aproblemoftenseenwithconstructedwetlandsisfecalsourcecontaminationduetowildlifefeces.Whilethesystemmaybeclearinghumanfecalsourcecontaminationfromtheoriginalinfluent,overallreadingsmaystillbehighorevenoverthemaximumallowablebacterialcountlevel,duetopresenceofanimalsthatareattractedtothewetlands.OnewaytopinpointthesourceofbacterialcontaminationisthroughacombinedmethodofDNAtestingknownasPolymeraseChainReaction(PCR)andsequenceanalysis.Inthismethod,bacterialDNAisamplifiedtodetectablelevelsthensequencedandcomparedtoknownhuman‐specificfecalbacterium.Theabsenceofhuman‐specificDNAmarkersexcludesthefecalsourceasahumancontaminant.3 BydeterminingthesourceoffecalcontaminationtheeffectivenessoftheCWcanalsobeevaluated.Ifthefecalsourceisdeterminedtobeofhumanoriginoperationalmanagerscanseeifflowrateistoohigh,resultinginlowretentiontimesorifadditionalmaintenanceisneeded.Ifthesourceisofnon‐humanorigin,problemwildlife,oftenmuskrats,canbeidentifiedandremovedthroughvariousmethods.Inadditiontohighfecalcontaminationreadings,muskratsandotherproblemwildlifemayleadtostructuraldamageofthewetlands.
1.4.3AdditionalsamplinglocationsIncludingadditionalsamplinglocationsbeyondwetlandinfluentandeffluentwouldbeusefulforevaluatingtreatmentperformanceofindividualwetlandcells,andinformingfuturewetlandmanagement.Theproposedpilotwetlandconsistsoftwocells,inpartbecauseonegoalofthedesignistheabilitytodrydownonecellwhilemaintainingtreatmentfunctionality.One
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currentuncertaintyistheflowpathofwaterthroughthesystem,astherearetwoalternatives.Oneoptionistosplitthewaterthatisdischargedfromtheprecedinglagoonamongthetwocells,whiletheotheristodirectallwaterthroughbothcellssequentially(Figure1).Thislatteroptionwouldpresenttheopportunitytouseadditionalmonitoringtounderstandthedifferencesintreatmenteffectivenessbetweenwaterthathasonlypassedthroughonecell,versuswaterthatisdischargedfromthetreatmentwetlands.Samplingwastewaterinfluent,effluentfromthefirstcell,andeffluentfromthewetlandwouldaddonemoresamplingpointandincreasethecostsandeffortrequiredformonitoring,butthesecostsmaybemarginalasthemajorityofthelaboratoryworkwilltakeplaceregardlessofthenumberofsampling
points.
InformationregardingthedifferenceintreatmenteffectivenessofonecellandbothcellswouldbevaluableindeterminingtheareaandflowraterequiredtoeffectivelytreatallwastewatercollectedbySUD.Forinstance,ifflowthroughonecellisnoteffectiveenoughtotreatwateradequatelyforfuturedrinkingwaterstorage,thesubsequentreductionofpollutantsbyasecondcellcouldbeextrapolatedtoinferthewetlandarearequiredtodoso.Alternatively,ifeffluentfromthefirstcellhasundergoneadequatetreatment,experimentationwithflowratemanagementcouldimproveknowledgeofacceptableresidencetimesforwaterinthecells,andallowthewetlandtooperatemostefficientlyintermsofbothcostandtreatment.InformationofthisnaturewouldalsobeusefultoTDECandothercommunitiesinpermittingandplanningfuturewetlands.
Tier1samplinglocations
Potentialadditionalsamplinglocations
Figure1: SamplinglocationsforTier1recommendationsandpotentialadditionalsamplinglocationsfortwowaterflowpossibilities:(A)sequentialwetlandcellsand(B)adjacentwetlandcells
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Ifthewetlanddesignissuchthatthewaterissplitbetweenthecells,ratherthanflowingthroughinsequence,additionalsamplingcouldpotentiallystilloccuralongthewaterflowpathineachcellinordertoattempttounderstandtherelationshipbetweentreatmenteffectiveness,waterresidencetime,andwetlandarea.Whilethiswouldbeamoreapproximateapproachduetothepotentialforwatermixingwithineachcell,itmaystillbeausefultechniquetoprovideinformationforestimatingnecessarytreatmentparameters.Ineithercase,additionalsamplingfrequencywouldalsobeanexampleandaresourceforothertreatmentwetlands,communities,regulators,andresearchers. 1.4.4Faunaandflora Anadditionalmonitoringpracticethat,whilenotnecessary,mayberelevanttowetlandoperationandfunctionismonitoringofwildlifevisitingthesite.Wildlifeoftenusetreatmentwetlandsashabitat,andsometreatmentwetlandsalsofunctionasconservationareasorwildlifepreserves.4Thiscancausemanagementconcerns,especiallywhenwastefromaquaticanimals(particularlywaterfowl)increasesthenutrientloadingandbacterialcontentofthewater(seeaboveformonitoringbacterialsource).Speciessuchasmuskratandbeaveralsosometimestakeupresidenceintreatmentwetlandsandcanalterflowbybuildinglodgesorerodebanksbyburrowing.Additionally,whiletreatmentwetlandsareapotentialaidtotheconservationanimalsthatusewetlandsashabitat,littleinformationisknownregardingthechroniceffectsoftoxinsinwastewateronwildlifethatusethewetlands,especiallythosepersistentorganicpollutantsknowntobioaccumulateinanimalsathighertrophiclevels.5Finally,thereisoftenconcernaboutprovidinghabitatfornuisancespeciesanddiseasevectors,suchasmosquitoes.
Monitoringofwildlifeuseoftheconstructedwetlandswouldinformfutureadaptivemanagement,helppreventharmtowildlifeandhumans,andincreaseecologicalknowledgeofthehabitationofwildlifeinconstructedwetlands.Dependingonthetimeandpersonnelavailable,wildlifemonitoringcouldbemoreorlessintensive.Potentialrecordedinformationmightincludesimplespeciessightings,abundancesofsignificantspeciesorspeciesofmanagementconcern(geese,blackbirds,threatenedorendangeredspecies,muskrats,beavers),evaluationofmosquitopopulationsduringseasonalpeaks,locationwithinwetlandsofhighestwildlifeuse,amongotherinformation.Alongwithwildlife,monitoringofinvasiveorexoticvegetationinthewetlandwouldbeusefultoscientistsstudyingplantinvasionandtowetlandmanagersalike.
Whilefrequentmonitoringwouldlikelybeimpossibleinconjunctionwithotherresponsibilities,monthlyorquarterlysurveysmaynotbecost‐prohibitive,andmightbyundertakeninpartnershipwithstudentsorcommunitymemberstominimizecostsandbuildsupport.Informationsuchasthiscouldberecordedinalog(similartomaintenancedata)withadateanddescription,andmadeavailabletoresearchers,regulators,andothercommunities.
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Togetherwithcitizensciencedata(seeTier3),thiskindofmonitoringcouldmaketheSUDwetlandahotbedoftreatmentwetlandresearchandinnovationforwildlifemanagement.
1.5Tier3monitoring Tier3monitoringpracticesdescribepotentialmonitoringthatshouldbeconductedinpartnershipwithathirdpartyorinresponsetopreviouslycollecteddataattheSUDwetland(adaptiveorexperimentalmanagement).Thistypeofmonitoringwouldincreasethescopeofthewetlandbeyondanexemplarywastewatertreatmentfacilitytosomethingofatreatmentwetland/researchstationcombination.ThiscouldbeanopportunityforSUDandtheSewaneecommunitytobecomeleadersintreatmentwetlandresearch,aswellaseducationalandpublicengagement.MonitoringofthistypewouldlikelyrequireaconcertedeffortonthepartofSUDtoengagethelocalcommunityandmembersofrelevantscientificfields,andsoshouldbecarefullyplanned;thebenefitscouldbegreat,however,asscientificinnovation,publicawareness,andwidespreadsupportwouldallbeextremelyvaluabletotheeffectivefutureoperationofasustainabletreatmentwetland. 1.5.1ResearchpartnershipsOnewaytooffsetcostsoflaboratoryanalysisistoopenthefacilitiestoallowuniversitygraduate/facultyresearch.Neighboringuniversities,suchasUniversityoftheSouth,alongwithR1institutes,liketheUniversityofGeorgia,oftenreceivegrantmoneythatmaybeusedtosubsidizeoff‐sitetestingiftheCWsiteisbeingutilizedforsamplecollection.Asmentionedpreviously,theSUDCWsiteholdsvaluableresearchpotentialnotonlyasthesecondCWinTN,butalsoasapotentialsiteformicro‐constituenttesting,i.e.pharmaceuticals.Additionally,researchuniversitiesfrequentlypurchaseandmaintainexpensiveanalyticalequipment,suchasaHighPerformanceLiquidChromatograph,thatcanbeutilizedbyfacultyandgraduateresearchers.Someteststhatareusuallysentoff‐sitetocommerciallaboratorieshavethepotentialtobeanalyzedatareducedratebyareputableuniversitylaboratory. 1.5.2Citizenscienceandpublicengagement Citizenscienceisanameforactivitiesthatinvolvethegeneralpublicincollectingscientificdatathatcanbeusefulforanalysisanddecisionmakingbyresearchersorresourcemanagers.Often,citizensciencedataisdatathatcouldnotbegatheredbyanyonepersonorgroupofresearchersduetothetemporalorgeographicscope,orthegeographicortemporalextent.Thenumberandexpertiseofinterestedcitizensisoftenacombinationthatcanproducedatathatotherwisewouldbeimpossibletoobtainandanalyze.
Acommonexampleofpublicinvolvementindatacollectionattreatmentwetlandsinvolvesbirdobservationandbirdcounts.AnumberofwetlandsinthesoutheastUnitedStates,andatleasttwointhestateofGeorgia(inClaytonCountyandGlennville)welcomecommunity
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membersontothesitetoconductinformalbirdsurveysorforrecreationalbirdwatching.TheE.L.HuiewetlandsinClaytonCountyevenconductmoreformalizedAudubonChristmasBirdCountsofaviandiversityandabundance(partofanationalprogram)onsiteinlateDecember.Muchofthisdata,formallyorinformallycollected,ispostedoneBird,adatabaseofbirdpresenceinformationcompiledbyamateurcitizensthroughoutthecountry.Thisdatabasecanthenbesearchedandanalyzedbyanyonewhowishestousethedata.Databasesalsoexistforothertypesofwildlifethatvisitwetlands,suchasladybeetlesandbutterflies.6
Beyondpublicengagementthroughcitizenscienceanddatacollection,thereareopportunitiesforrecreationalandeducationalprogramson‐site.ThetreatmentwetlandinAugusta,GAispartofthePhinizySwampNaturePark,andallowspublicrecreationalopportunities;WealsoknowofatleastthreewetlandsinGeorgiathatconducteducationalprogrammingwithlocalschoolsandcommunitymembers:inAugusta,ClaytonCounty,andLakeland.Ofthese,thetreatmentwetlandinLakeland,GAisofsimilarsizeastheproposedwetlandinSewanee,andhostsseveralhighschoolgroupseachyear.Educationalandrecreationalprogrammingcouldbeagoodopportunitytoengagethepublicwiththeactualmonitoringprogram(forwildlife,forinstance),andanyprogrammingofthisnatureshouldberecordedforfuturereferencewiththedate,natureofthepublicengagement,numberofparticipants,andsignificantfindings.
1.5.3Adaptivemanagementandexperimentation
BasedonsomeofthemonitoringpracticesinTiers1and2,informationislikelytobegleanedconcerningbestpracticesformanagementandoperationofthetreatmentwetland.Informationregardingsequentialtreatmentperformance,necessarywaterresidencetime,seasonalandweather‐dependentnutrientandpollutantremoval,andconsequencesofcertainmaintenanceactionscouldpotentiallybeusedtoimprovetheperformanceandefficiencyofthewetland.Thispracticeofadaptivemanagementmayrequiremoredataanalysisandreflectionthanisentirelypractical,butsmallmanagementadjustmentsbasedonsimpleobservationsoftreatmentperformanceunderdifferentconditionscouldbemadefairlyeasilyandcost‐effectively.
Finally,conductingasmallamountofexperimentationwouldbeanovelapproachtooperatingatreatmentwetland,andanotheropportunitytopushSUDtotheforefrontofresearchanddatacollectionintheconstructedwetlandandwastewaterfields.AsmostconstructedwetlandsoperateunderNPDESpermits,itisgenerallydifficulttojustifymanipulatingwetlandcharacteristicssimplytoincreaseknowledgeofhowthesekindsofsystemsoperate.TheSUDpilotprojectwouldnotbeconstrainedbyanNPDESpermit,andsomaybeanidealsystemtoperformsomeexperimentationthatwouldbeusefulinordertoinformfutureSUDwetlanddesignandmanagement,aswellasincreasegeneralknowledgeofconstructedtreatmentwetlandfunction..IntheeventofapartnershipwiththeUniversityoftheSouth,theUniversityofGeorgia,oranothercollegeoruniversity,orbecauseofstrongcommunitysupport,itcouldbeinformativeandpioneeringtoconductsmallmanipulationsofvegetationcover,height,
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speciescomposition,waterlevel,orothersafealterationstotheoriginalwetlanddesignandmonitoreffectsonwaterqualityandoperationalcharacteristics.
2.Communications
AnydecisionmaderegardingthepotentialuseofconstructedwetlandstotreatwastewaterinSewanee,TNmustconsidertheecological,financial,andsocialramificationsthat,together,createcomplexityanduncertaintyaroundthe“optimal”courseofaction.Ashasbeendemonstratedinprevioussections,evidencefrompeer‐reviewedstudiesandsuccessfulexamplesofotherconstructedwetlandsreducesomeuncertaintyandlendsupporttotheecologicalandfinancialbenefitsthatthistreatmentsystemoffers.However,theperspectivesofthosemostimpactedbythedecision,includingthegeneralpublic,mayconflictandimpedethedecisionmakingprocesssurroundingwatertreatment.Therefore,awell‐designedsocialmarketingcampaignisessentialtotheoverallsuccessofthepilotprogram.Suchacampaignshouldincorporatetheuseofavarietyofmediaoutletsandclearlyandeffectivelycommunicateprojectgoalsandbenefits.Amongstotherthings,themediacampaignshouldexplainthecurrentwatercycletothecommunity,describetheproposedplanstobuildthewetlands,elucidatethemanybenefitsofconstructedwetlands,andexplaintheprotocolsandproceduresthatwillbeusedtotestthetreatedwater. Further, successfulsocialmarketingcampaignsencourageeducation to takeplaceonseverallevels.Wastewaterdischarges to surfacewaters anddrinkingwater areheavily regulated intheUnitedStates.Assuch, localandstateofficialsneed tobe informedabout thepermittingprocessandoperationrequirementsfromtheconceptionofaproject.Additionally,themediaand thegeneralpublicmustbeeducated.Themedia canbeawastewaterprogram’sbiggestchampion or worst enemy and efforts must be made to keep them properly informedthroughoutthecourseoftheproject.Educationofthegeneralpublicwarrantsspecialattentionastheywillbetheonesmostgreatlyaffectedbytheproposedtreatmentsystems.TherearemanypotentiallyeffectivemechanismsforconveyingthegoalsoftheSewaneeUtilityDistrict (SUD) and the proposed constructed wetlands systems to all three aforementionedparties.Onesuchproventechniqueistheuseofmultimediaorfilm.SpurredbyrequestsfromSUD and the Southern Association of Colleges and Schools (SACS), two films were createdduring Spring 2013. The first film focused on SUD’s development of a pilot project thatwillassess the use of constructed wetlands as a potential wastewater treatment system forSewanee.Dovetailingwiththiseffort,asecondfilmwascreatedtohighlightthecollaborationbetweentheUniversityofGeorgia,UniversityoftheSouth(Sewanee),SewaneeUtilityDistrict,andClaytonCountyUtilityDistrict that involvedacademics,municipal employees, graduates,andundergraduatestudents.
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2.1.ConstructedWetlandEducationVideoIn the spring of 2013, students of the Environmental Practicumwere commissioned by theSewanee Utility District to create a 10‐minute video describing constructed wetlands. ThisvideowillultimatelybeplacedonSUD’swebsiteandserveasa tool tomarket thewetlandsprojectandgarner thesupportofmultiple stakeholders, including localdecisionmakers, thegeneralpublic,andotherutilitydistrictsinterestedinimplementingsimilartreatmentsystems.Specifically, the film’s content was designed to educate stakeholders in and around theSewanee community about constructed wetlands and the status of SUD’s pilot project,represent and address public perceptions surrounding thewetlands, and highlight potentialbenefitsofconstructedwetlandstothecommunity.The footage for thevideowasshotbetweenFebruaryandApril2013 in locations inGeorgiaandTennessee.AninitialtriptotheClaytonCountyWetlandsinJonesboro,GeorgiawasmadeinFebruary,butinclementweatherlimitedtheamountofusablefootage.Still,thistripinitiatedcollaboration between UGA students and faculty, Sewanee students and faculty, and utilitydistrict employees. A subsequent trip was made by graduate student, Greg Skupien, andprofessor,LaurieFowler,onApril11th.Duringthisvisit,anin‐depthinterviewwasconductedwithDonnieKiblinger,NaturalTreatmentSystemsSupervisor,andfootageofthewetlandswastaken.AnadditionaltripwasmadetoSewanee,TNonMarch21stbygraduatestudentBrianCrawfordandAmble Johnson to conduct interviewswith severalmembersof theSewanee communitythat share a stake in the pilot program. In‐depth interviews were conducted with twoprofessorsand long‐timeSewaneeresidents,Dr.DeborahMcGrathandDr.MartinKnoll, andSewaneeUtilityDistrict Supervisor,BenBeavers.UGAstudentsalso took thisopportunity tomentor Sewanee undergraduates in conducting further interviews of Sewanee students,faculty, and other community members. These short face‐to‐face surveys were designed togaugelocalpeople’sknowledgeandattitudesofconstructedwetlandsystems.ThesequestionswereanelaborationofasurveyadministeredbySewaneestudents inthepreviousyear.Thequestionstothese,andallinterviews,canbefoundinAppendixE.Further,aninterviewwithDr.RonCarroll,wetlandsexpertandco‐professoroftheEnvironmentalPracticum,wasconductedinmid‐AprilonthecampusoftheUniversityofGeorgia.FilmeditingandproductionwasdonebyAmbleJohnstonoftheUniversityofGeorgia’sRiverBasinCenter.
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2.2.CollaborationVideo
During the developmental phase of the Sewanee Utility District ConstructedWetlands PilotProgram graduate students enrolled in the Environmental Practicum at the University ofGeorgiaandundergraduatesat theUniversityof theSouthhaveworkedtogethertodesignamonitoringandmarketingprotocol to facilitate implementationof the constructedwetlands.Guided by facultymembers, andworkingwith both the Sewanee andClaytonCountyUtilityDistricts,studentshaveparticipatedinatrulyuniquecollaborationeffort.
Addingtotheuniquenessofthecollaborationarethecontrastingdifferencesbetweenthetwouniversities.TheUniversityofGeorgiaisalarge,tieroneresearchuniversitylocatedinAthens,GA.ThegraduatestudentsintheEnvironmentalPracticumrepresentgraduatestudentsfromthe Odum School of Ecology, Warnell School of Forestry, School of Law, and College ofEnvironment and Design. These graduate students tend to be more myopic; focusingpredominatelyontheirownresearch.StudentsfromtheUniversityoftheSouth,asmallliberalarts university located in the townSewanee, TN, possess local knowledge of the communityandhaveabroaderworldview.
Given the nature of the collaboration, the Southern Association of Colleges and SchoolscommissionedtheUniversityofGeorgiatoproduceashort,10‐minutevideodocumentingthecollaborationbetweenthesetwodistinctuniversities.Thisvideowasmadeoverthecourseoffour months (January – April 2013). Graduate students from the University of Georgia andundergraduates from the University of the South first met on February 7th at the ClaytonCountyConstructedWetlandsinJonesboro,GA.Duringthisvisit,studentsbecameacquaintedwitheachother, learnedabouttheprocessofwastewatertreatmentandtouredthefacilities.Afterthis initialmeetingmanyundergraduatesexpressed interest inassistingwiththesocialmarketingandcommunicationaspectoftheproject.
OnMarch14,graduatestudentBrianCrawfordandexperiencedvideographerAmbleJohnsontraveled to Sewanee tomeetwith students and conduct interviews for the film. During thisvisit, undergraduateswere instructed on how to conduct interviews and how to use filmingequipment.With thisknowledge,undergraduateswere free to conduct additional interviewsduringthemonthofApril.Thisfootagewasincorporatedintothefilm.3.PossibleIncomeSourcesfromaConstructedWetlandAsmentionedpreviously,themainpurposeofthisproposedconstructedwetlandistoprovidewaterfiltrationandremovalofexcessnutrientsfrommunicipalwastewateraswellasadditionalwaterstoragecapacityintimesofdrought.Wetlandsalsoprovidecriticalhabitatforaquaticandwetlandspecies;habitatwhichhasbeenlostforcenturiesintheUnitedStates.Infact,DahlandAllordoftheUSGeologicSurveyestimatethatoverhalfofallwetlandsthatexistedintheUShavebeendestroyedsinceEuropeancolonization,withlossestotalingwellover100millionacres.7Asaresult,constructedwetlandsprovidevaluableservicestoboth
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humansandwetlandfauna.Itmaybepossibletofurtherleveragethefunctionsofaconstructedwetlandbyusingitsproductsandservicestocreateanincomesourceordisplacecoststhatcouldthensupplementtheexpensesofmaintenanceandupkeep.Fivepossiblesourcesofincomefromconstructedwetlandshavebeenidentified:biomasstocompost,biomasstofuelpellets,biomasstobiogas,biomasstocellulosicethanolandcarboncaptureforcarbonoffsetcredits.Theseoptionsvaryinbothfeasibilityandincomepotential,butalloptionscreateapositiveimpactonreducinggreenhousegases.Thefirstfouroptionsallrequiretheharvestingofbiomassfromtheconstructedwetland,sothisprocedurewillbediscussedfirst.ThebiomassofaconstructedwetlandintheSoutheastconsistsprimarilyofthecommoncattail,Typhalatifolia.Cattailsarepervasivebecausethemainbrownbarbofacattailconsistsofthousandsoftinytightlypackedseedswhichwhenreleaseddisperseviathewindandcolonizeotherareasandwetlands.Cattailsgrowquicklyandareabletotakeadvantageofthehighlevelsofnitrogenandphosphoruspresentinmunicipalwastewater.Foraconstructedwetlandtofunctionatahighlevel,itmusthavebothdeepandshallowsections,whichallowthewastewatertoflowthroughthewetland.Thisisoftenachievedbyburningthecattailswithamixtureofdieselandgasolineatvariouspointsduringtheyearsothattheplantsdonotcompletelyovertakethedeepzonesandslowtheflowofwater(DonnieKiblinger,SupervisorE.L.“Ed”HuieJr.NaturalTreatmentSystems,ClaytonCountyWaterAuthority,2/7/2013).Theremovalofthebiomassalsofostersgreatergrowthandnutrientremovalbecausetheplantsexperiencelesscrowding.Insteadofsimplyburningthisbiomass,itcouldbeputtootherusesthatcouldbenefitSUD.Tousethisbiomassinanyway,itmustfirstbeharvestedfromthewetland.Thisisachievedbytemporarilydrainingthewetlandtoallowtractorsorothertypesofharvestingequipmentaccesstotheplants.TheSewaneeconstructedwetlandisdesignedwithtwocellsforthispurpose,soonecellcanbedrainedwhiletheothercontinuestooperatenormally.Harvestersthatworkinwetlandareasusuallyemploycaterpillartracksorwide,oversized“balloon”tires.Thesetreadsortiresdistributetheweightoftheequipmentsothatthesoilisnotcompactedasamuchtoallowforbetterregrowthoncetheharvestiscompleteanditalsoensuresthattheequipmentdoesnotsinkinthesoftsoilofthewetland.8Theseharvesterscanbescaledforanysizedwetland,fromsomethingsimilartoanATVthatmightbeappropriateforthispilotproject,toalargetractorwithanintegratedtrailertocutandcollectbiomassfrommuchlargerwetlands.Ifnecessary,theharvestedcattailscanthenbebaledlikehay,alfalfaorothergrasscrops.9OnebrandofvehiclethatmaysuittheneedsofwetlandharvestingforthisproposedpilotprojectisArgo.Argomakesamphibiousutilityvehiclesthathave6or8wheelsandrubbertracksareoptionalequipmentaswell.10ArgoUTVsrangeinpricefrom$10,000to$25,000forthetopoftheline.SLEEquipmentinAntioch,TNisanArgodealerandmightbeabletoprovideadviceonwhichvehiclewouldbethebestsuitedtoharvestingwetlands.Also,purchasingausedvehiclecouldbeanoptionaswell.11Pleasenotethatthereareother
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manufacturersof6and8‐wheeledamphibiousvehiclesthoughtheArgobrandseemstobethemostwellknown.Finally,RichardGrosshansandothersattheInternationalInstituteforSustainableDevelopment(IISD)inWinnipegcouldbecontactedregardingtheirexperience,sincetheypictureanArgoUTVwithacustombuiltsicklebarmowerharvestingcattailsintheirpublishedwork.12
3.1.BiomasstocompostOncethisbiomassisharvestedthereareseveralpossibilities.Perhapsthemostviableoptionthatcouldbeimplementedsoonafterthewetlandisestablished,iscompostingthebiomass.Compostingbreaksdownthecattailsandothervegetation,releasingthenutrientstobeappliedtocropsorlandscapingontheSewaneedomain.ThisoptioncouldevenbecombinedwithcurrenteffortsbySewaneeDinningand“TeamCompost,”astudentcompostinginitiative,thatworktocompostfoodwastefromdininghalls.13Thebiomassfromtheconstructedwetlandscouldbeaddedtothisprogramtoincreasetheamountofcompostavailabletotheuniversity.Integratingthecompostingofbiomassintothecurrentprogramwouldmostlikelybethebestoptionbecausethespike,stemandleavesofcattailshaveacarbontonitrogen(C:N)ratioof15:1.14However,forcomposttobeeffective,itisrecommendedthattheC:Nratiobe25‐30:1.15Therefore,thecattailbiomassshouldbemixedwithothertypesofbiomasstoattainthecorrectC:Nratioforoptimumcompostefficiency.Sincethecompostinggroupalreadyhasexperiencewiththis,itshouldbefairlystraightforwardtointegratethecompostingofthecattails.Compostingthewetlandbiomasswouldbeanetpositiveforthereductionofgreenhousegasesbecausethecattailsabsorbcarbondioxideandthenthatcarbonisreturnedtothesoilandnottotheatmosphere.Also,usingthenutrientsofthecomposttofertilizecropsandlandscapingreducesoreliminatesneedfortheconventionalpetroleumbasedfertilizers.Finally,iftheadditionofthewetlandbiomassmeansthatthereisexcesscompostthattheuniversityisunabletouse,itcouldbesoldtointhelocalcommunity.
3.2.BiomasstofuelpelletsAnotherpossibleuseforthewetlandsbiomassisthecreationoffuelpelletsforuseinfurnacesorpelletstoves.Fuelpelletsaremadebygrindingthebiomasstoapulpandthencompressingitintosmallcylinders.Traditionally,thesepelletsaremadefromhardwoods,butothertypesofbiomassarebeingincorporatedintothesepelletsaspeoplelookformoresustainablesolutionsforheatingbuildings.16Fuelpelletsarepopularbecausetheyhaveaveryefficientburncomparedtofireplacesorwoodstoves,producinglesssmokeandreleasingmoreheatperunitoffuel.Cattailfuelpelletshaveahigherashcontentcomparedtohardwoodpellets,sooneresearcherrecommendsthatcattailbiomassbemixedwithothersourceswithlowerashcontenttoproduceahighquality,lowashpellet.17Cattailshaveaverycomparableenergydensitycomparedtohardwood,withcattailpelletsproducing16‐20megajoules(MJ)ofenergy
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perkilogram(15,164‐18,965Btu/kg)whilehardwoodpelletsproduce17‐18MJ/kg(16,112‐17,060Btu/kg).18Sewaneehasalreadyexploredtheoptionofusingfuelpelletsforheatingandtosell,however,noactionhasbeentakenasofyet(NathanWilson,SewaneeDomainManager,4/16/2013).Anotheroptionforproducingfuelpelletsmightbeapartnershipwithlumbercompaniesthataremakingthepellets.TherearetwocompaniesinTennesseethatproducepellets:HassellandHughesLumberCompanyinCollinwoodandHenryCountyHardwoodsIncorporatedinParis.Thesecompaniesmightbearesourcetolendexpertiseortheymightbeabletoincorporatethewetlandbiomassintotheirpellets.Again,thismethodofusingtheproductionofthewetlandsreducesgreenhousegasemissionsbydisplacingthefossilfuelsthatwouldhavebeenusedtoheatbuildingsheatedinsteadbyfuelpellets.
3.3.BiomasstobiogasConvertingthewetlandbiomasstobiogasisanotherwaytoleveragetheservicesoftheconstructedwetlands.Themainconstituentofbothbiogasandnaturalgasismethane,howevertheydifferbecausebiogascontainscarbondioxide,whilenaturalgasismostlyotherhydrocarbons.However,biogascanbepurifiedandusedasareplacementfornaturalgas.Biogasisproducedbyputtingorganicmaterialsintoabiodigester,wherebacteriabreakthemdownintheabsenceofoxygen.19Normallywhenorganicmatterisbrokendowninthepresenceofoxygen,carbondioxideisproduced.However,intheabsenceofoxygen,bacteriaswitchtoanaerobicrespirationandthebyproductofthatrespirationismethane.Thismethanethenrisestothetopofthebiodigesterwhereitflowsthroughapipewhereitcaneitherbeburnedimmediatelyorstored.Researchersstudyingtheanaerobicbreakdownofcattailshaveaddedcockroachgutmicroorganismtotrytoenhancetheproductionofmethane.Theseresearchersfoundthatmaximummethaneproductionwasachievedwhenthepercentofcattailswerelowrelativetootherorganicmatter.20Thus,thisisanotherexample,similartothefuelpellets,wherethemaximumbenefitfromthisstrategymaynecessitatecombiningthewetlandsbiomasswithothersourcesofbiomasstoachieveoptimalefficiencyinthebiodigester.AnotherreasonthismaybeaviableuseofthewetlandbiomassisthatSewaneeSustainabilityMasterPlanreportsthatbiogasproductionhasalreadybeenconsideredfordealingwithfoodwasteattheuniversity.21
3.4.BiomasstocellulosicethanolThefinalpossiblewaytousebiomassharvestedfromconstructedwetlands,isusingitasafeedstocktoproducecellulosicethanol.Thisiscurrentlyleastviableofthebiomassoptions,however,itmaybecomeeasierinthefutureastechnologyimproves.Cellulosicethanolisethanolproducedfromnon‐foodcrops,suchascattails,frombreakdownofthecomplexmolecule,celluloseintosimplesugars.Thosesimplesugarsarethenfermentedtoproduceethanol.22Thisethanolcanthenbeblendedwithgasolineatvariouspercentagestobeusedingasolinepoweredvehicles.Themainchallengetothisprocessisthecelluloseitself.The
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moleculeisdifficulttobreakdownbecauseitformsacrystalandiswater‐insoluble.Asaresult,manyresearchersareworkingontechniquesusingbothchemicalsandspecializedenzymestomakethedigestionofcellulosefaster.23Thoughcellulosicethanolcanbemadeinalabinsmallquantities,itisdifficulttoscaleupthoseprocessestothemillionsofgallonsnecessarytoreplacethecurrentrateofUSgasolineconsumption,approximately357milliongallonsperday.24Totrytospurgrowthinthemarket,a$1.01pergallonfederaltaxcreditwasissuedin2007aswellasmandatoryusagerequirements.25Despitetheseincentives,cellulosicethanolhasnotbeencommerciallysuccessfulatalargescalethusfar.Iftheproductionofcellulosicethanoleventuallybecomeswidespread,itwillhaveamajorimpactongreenhousegasemissionssinceitrequiresmuchlessenergyinputandproduces86%lessCO2duringitslifecyclecomparedtogasoline.26
3.5.CarbonoffsetcreditsThelastpossiblewaytouseconstructedwetlandsasanincomesourceandtoreducegreenhousegasemissionsistosellcarbonoffsetcreditforthecarbondioxidecapturedbythewetlands.However,sellingcarboncreditsforaconstructedwetlandisatenuouspropositionatbestforthetimebeing.Whilemanypublicationshavelookedatthecarbonbudgetsofnaturalwetlands,fewpublicationshavespecificallystudiedconstructedwetlandemissionsandsequestration.27Thosethathave,reportmixedresultsregardingwhetherconstructedwetlandsareacarbonsinkorsource.Evenunderthebestcircumstances,constructedwetlandshavebeenreportedtosequester8.4metrictonsofcarbonperacreperyear,whichisequivalentto30.9metrictonsofcarbondioxide.Thisvaluerepresentsdatacollectedin2001;howeverthisvaluedecreasedto23metrictonsofcarbondioxidein2002.Itwasalsoreportedthatsince2002carbonsequestrationhascontinuedtofallinthisparticularwetlandasaresultofchangesinthesoilandmicrobialcommunities.28Otherstudieshavereportedmuchlowersequestrationrates.29Inaddition,thesedatadonotincludeemissionsofmethaneandnitrousoxide,which,accordingtotheUSEPA,have21timesand300timesthewarmingimpactcomparedtocarbondioxide,respectively.30Therefore,eventhoughtheemissionsofCH4andN2Ofromconstructedwetlandsissmallcomparedtocarbondioxide,theamountofcarbonsequesteredbythewetlandswillbesomewhatcounteractedbythesenegativeemissions.
CarboncreditsaretradedinmarketsaroundtheworldandvariousregionshavetheirowntradingschemeincludingCalifornia,theNortheastandMid‐AtlanticStatesaswellasEurope.31Thesemarketsarenotfullydevelopedandoftenrelyonvoluntaryparticipation.Recently,thecarbontradingmarketinEuropesawthepriceofonemetricton(t)or1,000kgofcarbondioxide,thestandardunitforcarbontrading,fallbelow3Eurosor$US3.95fromahighof31Eurosatonin2006.32TheCaliforniacapandtradeprogramheldanauctiononFebruary2,2013forcarbonallowanceswhichsoldfor$13.62/tandseveralcompaniesoffercarbonoffsetsthatcanbepurchasedonline.33Terrapasssellscreditsfor$13.33/tandNativeEnergysellscreditsfor$15.86/t.34Interestingly,thepriceofcarbondioxidecanvarysignificantly,eventhoughitisthesamemoleculethroughouttheworld.Finally,neithertheCalifornianorthe
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Northeastcarbonmarketscertifiesconstructedwetlandsforoffsetcreditscurrently,butascarbonmarketsmaturethatmaybecomemoreofapossibility.Thisiswhycarboncreditsaretheleastfeasibleofalltheoptionsforleveragingtheservicesoftheconstructedwetlands.
3.6.FinalAssessmentofIncomeSourceOptionsInconclusion,themostviableoptionforimmediateuseoftheconstructedwetland’sservicesiscompostingtheplantmatterinconjunctionwiththecurrentcompostprogramthatisalreadyinplaceatSewanee.Thetwooptionsthatarefeasibletoaccomplish,butwouldtakemoreofaninvestmentarethefuelpelletandbiogasoptions,however,thefuelpelletoptionmightbepreferablebecauseofeaseofuse.Ifanytypeofharvestingisconsidered,itwouldbebeneficialtoreadaboutandcontacttheIISDinWinnipeg,Canadabecausetheyareonthecuttingedgeofthisfieldofresearch.35Lastly,itseemsthatneithercellulosicethanolnorcarboncreditsarecurrentlyviableoptionsbecauseofthemanychallengespreviouslymention.However,technologyandmarketsdochangequicklyandtheseoptionsmaybecomemorefeasiblein5to10years’time.
1Darby,J.,M.Heath,J.Jacangelo,F.Loge,P.Swaim,andG.Tchobanoglous.1995.ComparisonofUVIrradiationtoChlorination:GuidanceforAchievingOptimalUVPerformance.WaterEnvironmentResearchFoundation.Alexandria,Virginia.2UnitedStatesGeologicalSurvey(USGS).2013.ToxicSubstancesHydrologyProgram.toxics.usgs.gov/highlights/pharmaceuticals_method.html.Accessed4/29/2013.3Shanks,O.C.,J.W.Domingo,J.Lu,C.A.Kelty,andJ.E.Graham.2007.IdentificationofBacterialDNAMarkersfortheDetectionofHumanFecalPollutioninWater.AppliedandEnvironmentalMicrobiology73:2416‐2422.4UnitedStatesEnvironmentalProtectionAgency.1993.EPA832‐R‐92‐005:ConstructedWetlandsforWastewaterTreatmentandWildlifeHabitat.Fleming‐Singer,M.S.,andA.J.Horne.2006.Balancingwildlifeneedsandnitrateremovalinconstructedwetlands:ThecaseoftheIrvineRanchWaterDistrict'sSanJoaquinWildlifeSanctuary.EcologicalEngineering26:147‐166.Worrall,P.,K.J.Peberdy,andM.C.Millett.1997.Constructedwetlandsandnatureconservation.WaterScienceandTechnology35:205‐213.5Coogan,M.A.,andT.W.LaPoint.2008.Snailbioaccumulationoftriclocarban,triclosan,andmethyltriclosaninaNorthTexas,USA,streamaffectedbywastewatertreatmentplantrunoff.EnvironmentalToxicologyandChemistry27:1788‐1793.Kadlec,R.H.,andS.D.Wallace.2008.Treatmentwetlands.CRCPress,BocaRaton,Florida.6http://www.ebird.org.http://www.monarchwatch.org.https://legacy.mos.org/fireflywatch.http://www.lostladybug.org.Accessed4/29/2013.7Dahl,T.E.,andG.J.Allord.1996.HistoryofWetlandsintheConterminousUnitedStates.UnitedStatesGeologicSurvey.Availableonlineat:http://water.usgs.gov/nwsum/WSP2425/history.html.Accessed4/16/20138Grosshans,R.E.2012.TheNetley‐LibauNutrientBioenergyProject:Findinginnovativesolutionsforwetland,restoration,flooding,phosphorus,andbioenergy.InternationalInstituteforSustainableDevelopment,Winnepeg,Manitoba,Canada.Availableonlineat:http://www.redriverbasincommission.org/Conference/Proceedings/29th_Proceedings/Grosshans_‐RRBC_2012.pdf.Accessed4/12/20139Grosshans,R.E.2012.SeeNote8.10ArgoUTV.2013.UtilityVehicles.http://www.argoutv.com/utility/utilityhome.aspx.Accessed4/26/2013.11SLEEquipment2013.UtilityVehicles.http://sleequipment.com/categories/utility‐vehicles/argos.html.Accessed4/26/2013.12Grosshans,R.E.2012.SeeNote813SewaneeDining.2013.Sustainability.http://dining.sewanee.edu/sustainability.Accessed4/14/2013.
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14Mshandete,A.M.2009.TheanaerobicdigestionofcattailweedstoproducemethaneusingAmericancockroachgutmicroorganisms.JournalofAgriculturalandBiologicalScience4:45‐57.15Composting101.2013.ABalancingAct(Carbon‐to‐NitrogenRatios).http://www.composting101.com/c‐n‐ratio.html.Accessed4/14/2013.16DanielCiolkosz.2009.RenewableandAlternativeEnergyFactSheet:ManufacturingFuelPelletsfromBiomass.PennStateBiomassEnergyCenterandDepartmentofAgriculturalandBiologicalEngineering,UniversityPark,PA.Availableonlineat:extension.psu.edu/pubs/uc203.Accessed4/14/2013.17Austin,A.2011.Manitobaresearchersconvertcattailsintopellets.BiomassMagazine.Availableonlineat:http://biomassmagazine.com/articles/5338/manitoba‐researchers‐convert‐cattails‐into‐pellets.Accessed4/12/2013.18Austin,A.2011.Anunconventionalpelletfeedstock.PelletMillMagazine.Spring2011:37‐41.Availableonlineat:issuu.com/bbiinternational/docs/spring11_pmm?mode=a_p.Accessed4/26/2013.19U.S.DepartmentofEnergy.2013.AlternativeFuelsDataCenter.http://www.afdc.energy.gov/fuels/.Accessed4/15/2013.20Mshandete,A.M.2009.Seenote14.21OfficeofEnvironmentalStewardshipandSustainability.2013.SustainabilityMasterPlan:Draft.Sewanee:UniversityoftheSouth.Sewanee,TN.Availableonlineat:http://sei.sewanee.edu/assets/uploads/2013_01_14_Sustainability_Master_Plan_Draft_for_Public_Forum_4.pdf.Accessed4/16/2013.22U.S.DepartmentofEnergy.2013.SeeNote19.23Dadi,A.P.,C.A.Schall,andS.Varanasi.2007.Mitigationofcelluloserecalcitrancetoenzymatichydrolysisbyionicliquidpretreatment.AppliedBiochemistry&Biotechnology136:407‐421.24U.S.EnergyInformationAdministration.2012.EstimatedU.S.gasolineconsumptionlowcomparedtofive‐yearaverage.http://www.eia.gov/todayinenergy/detail.cfm?id=7510.Accessed4/14/2013.25“TheCellulosicEthanolDebacle,”TheWallStreetJournal,December,142011.Availableonlineat:http://online.wsj.com/article/SB10001424052970204012004577072470158115782.html.26U.S.DepartmentofEnergy.2013.SeeNote19.27Mandera,U.,K.Lõhmusa,S.Teitera,T.Mauringa,K.Nurka,andJ.Augustind.2008.Gaseousfluxesinthenitrogenandcarbonbudgetsofsubsurfaceflowconstructedwetlands.ScienceofTheTotalEnvironment404:343‐353.Piceka,T.,H.C.Cizkovab,andJ.Duseka.2007.Greenhousegasemissionsfromaconstructedwetland—Plantsasimportantsourcesofcarbon.EcologicalEngineering31:98‐106.Teiter,S.,andU.Mander.2005.EmissionofN2O,N2,CH4,andCO2fromconstructedwetlandsforwastewatertreatmentandfromriparianbufferzones.EcologicalEngineering25:528‐541.28Mandera,U.,K.Lõhmusa,S.Teitera,T.Mauringa,K.Nurka,andJ.Augustind,2008.SeeNote27.29Piceka,T.,H.C.Cizkovab,andJ.Duseka.2007.SeeNote27.30U.S.EnvironmentalProtectionAgency(EPA).2013.GlobalWarmingPotentialDescribesImpactofEachGas.http://www.epa.gov/climatechange/ghgemissions/gases.html.Accessed4/15/2013.31CaliforniaAirResourcesBoard(CARB).2013.Cap‐and‐Trade‐Program.http://www.arb.ca.gov/cc/capandtrade/capandtrade.htm.EuropeanCommission.2013.TheEUEmissionsTradingSystem.http://ec.europa.eu/clima/policies/ets/index_en.htm.RegionalGreenhouseGasInitiative(RGGI).2013.http://www.rggi.org/.Accessed4/16/2013.32BusinessWeek.2013.CarbonfallsmosteverafterEUparliamentrejectsfix.http://www.businessweek.com/news/2013‐04‐16/carbon‐falls‐most‐ever‐after‐eu‐parliament‐rejects‐surplus‐fix.Accessed4/16/2013.33CaliforniaAirResourcesBoard(CARB).2013.SeeNote31.34NativeEnergy.2013.HousholdCalculator.http://www.nativeenergy.com/household‐carbon‐calculator.html.Terrapass.2013.TerrapassCarbonOffsets.http://store.terrapass.com/store/c/18‐Carbon‐offsets.html.Accessed4/15/201335Grosshans,R.E.2012.SeeNote8.