1Bruce Kobelski and Sean PorseU.S. Environmental Protection AgencyOffice of Ground Water and Drinking WaterWashington, D.C.Geologic Sequestration of Carbon DioxideCurrent GS Rule Development and ResearchScience Advisory Board Engineering CommitteeAugust 16, 20102OutlineUIC Program BackgroundWhat is Geologic Sequestration?Proposed GS Rule and ScheduleLBNL Research in Support of GS RuleUIC GS Guidance3UIC Program BackgroundThe 1974 Safe Drinking Water Act (Reauthorized in 1996)Minimum federal regulations forprotection of Underground Sourcesof Drinking Water (USDWs)USDW defined:Any aquifer or portion of an aquifer that contains water that is less than10,000 PPM total dissolved solids or contains a volume of water suchthat it is a present, or viable future, source for a Public Water SupplySystemUIC Program regulates underground injection ofallfluids–liquid, gas, or slurryDesignation as a commodity does not change SDWA applicabilitySome natural gas (hydrocarbon) storage, oil & gas production, andsome hydraulic fracturing fluids exemptedExisting UIC program provides a regulatory framework(baseline) for the Geologic Sequestration of CO24UIC Well Classes (Proposed)5What is GeologicSequestration?Courtesy of CO2CRCCCS ProcessTarget Formations6EPA’s GS Rule DevelopmentCollaborative EffortIn 2004 EPA’s Offices of Water andAir and Radiation started working inearnest on CCS and GS:Clarify and address issues acrossEPA statutes (SDWA, CAA, etc.) andProgram Offices (OW, OAR, ORD, OSWER)Coordinate technical and cost analyses for proposed regulation: 2007Workgroup of ~48 members includedDOE and 4 States (Texas, Arkansas,Alabama and Ohio)EPA closely collaborated with theDepartment of Energy (CCS Lead)EPA also coordinated with:Department of TransportationBureau of Land ManagementUnited States Geological SurveyStates, NGOs, ElectricPower Industry, Oil and Gas, Trade Groups7Special Considerations for GSLarge VolumesBuoyancyViscosity (Mobility)CorrosivityIEPA’s Proposed GS Rule:Approach to RulemakingUIC Program ElementsSite CharacterizationArea Of ReviewWell ConstructionWell OperationSite MonitoringWell Plugging and PostInjection Site CarePublic ParticipationFinancial ResponsibilitySite ClosureDevelop new WellClass for GS –Class VI8EPA’s GS RulemakingScheduleLate 2010/Early 2011Final UIC Rule for GS of CO2Post-rule publicationImplementation of UIC Rule for GS of CO2CompletedTechnical Workshops & Data CollectionDecember 2007/February 2008Stakeholder MeetingsAugust 31, 2009Notice of Data AvailabilityJuly 15, 2008Administrator’s Signature of Proposed RuleTimeframeActivity9Lawrence Berkeley NationalLaboratory ResearchLawrence Berkeley National Laboratory Researchin Support of Rule EffortInitial work on CO2Injection started in 2005; focusedon GS technology and analogsIn 2007 LBNL began an effort to model ground waterquality changes related to the mobilization of traceelementsAlso modeled basin-scale hydrologic impacts of CO2storage (both projects relate to potential risks posed toUSDWs from large-scale CO2injection)10Lawrence Berkeley NationalLaboratory ResearchModeled Ground Water Quality Changes Relatedto the Mobilization of Trace ElementsIdentity naturally occurring minerals that could act as asource of trace elements in ground water if they were tocome into contact with CO2Indirectly substantiated through an evaluation of morethan 38,000 water quality analyses from the USGS’National Water Information System (NWIS)Results of this modeling obtained for typical aquifersunder reducing conditions indicate that certain elementscould potentially exceed Federal drinking waterstandards at elevated CO2concentrations11Lawrence Berkeley NationalLaboratory ResearchAqueousConcentrationsat ElevatedCO2Concentrations(initial pH =7.6, reducingconditions,calcitesaturation)12Lawrence Berkeley NationalLaboratory ResearchModeled Ground Water Quality Changes Related to theMobilization of Trace ElementsLBNL used the reactive-transport model TOUGHREACT to studyand predict the transport of CO2within a shallow aquifer andmodel potential geochemicaleffects in the subsurfaceResults suggest the potential for mobilization of arsenic and lead tobe enhanced within certain ground watersThe MCL for arsenic was exceeded in only a few simulationscenarios, while the lead concentrations remained below the ALunder all scenariosIt is important to emphasize thatthese studies looked at potentialconsequences of CO2leakage into the USDW, not the likelihood ofsuch leakage occurring13Lawrence Berkeley NationalLaboratory ResearchModeled Basin-Scale HydrologicImpacts of CO2StorageLBNL studied a hypothetical, futurescenario of GS in a sedimentary basin asan illustrative example to demonstratethe potential for basin-scale hydrologicimpacts of CO2 storageThe model assumed a scenario where20 independent GS projects eachinjected 5 million tonnes of CO2over 50 yearsModel Domain: 570 km by 550 km(354 miles by 342 miles)Birkholzer et al, 200814Lawrence Berkeley NationalLaboratory ResearchModeled Basin-Scale HydrologicImpacts of CO2StorageSimulation runs indicated thatinjection pressures did notexceed fracture pressure or themaximum value used in themodel for this basin.Results indicated that farfieldpressure changes (in bars) couldpropagate as far away as 200 kmfrom the core injection areaPredicted pressure changescould push saline water upwardinto overlying aquifers iflocalized pathways such asconductive faults existed.Birkholzer et al, 200815Lawrence Berkeley NationalLaboratory ResearchEvaluating the Consequences of CO2Intrusion intoGroundwater: Laboratory Experiments,Microspectroscopy, and Associated GeochemicalModelingAquifer water and mineralogy from select US basins will becharacterized, and controlled laboratory experiments will beconducted to assess the potential mobilization of hazardousconstituents by dissolved CO2Current Work:Characterizing sediment and mineralogy samples from aquifers belowthe Plant Daniel site in Escatawpa, MississippiSetting up laboratory experiments for well-mixed flow throughreactors to expose sediments to from these aquifers to different levelsof CO216EPA’s Proposed GS RuleAdditional Effort on Technical GuidanceEPA will eventually produce 12 Technical Guidancedocuments and/or manuals on subtopics within the GS ruledesigned to assist owners and operators as well as regulatorsThe first Technical Guidance documents and/or manuals willcover the following areas:Site characterizationArea of ReviewMonitoring and TestingWell ConstructionFinancial ResponsibilityImplementation and Class VI PrimacyPlan Development17Thank you!More information about the UIC ProgramEPA Geologic Sequestration of Carbon Dioxide Website –http://www.epa.gov/safewater/uic/wells_sequestration.htmlCode of Federal Regulations: Underground Injection ControlRegulations 40 CFR 144-148 –http://ecfr.gpoaccess.gov/cgi/t/text/textidx?sid=d6ee71a544eca89c533c825135913f13&c=ecfr&tpl=/ecfrbrowse/Title40/40cfrv22_02.tpl