Evaluating Interactions of Fracturing Fluidsand Degradation Products with RadionuclidesandDegradationProductswithRadionuclidesContained in Organic-rich Solid-phase HostMaterialsZoltan SzaboU.S. Geological SurveyNORM in Produced Waters:Analogue studies characterization of bedrockAnaloguestudies,characterizationofbedrock,radionuclide occurrence, geochemistry, & wastes•CharacterizeU,Rotiramixintharacterizea,hersotopeatiosndturesheproduced waters. What isotopes account for the radioactivity?• Determine U and Ra-226 occurrence in the solid matrix of theblack shale togain understandingof the source and thepotentialg pfor mobilization• Define or design benchtop experiments and/or models to predictlikelychanges inproduced water concentrations of radionuclidesgp(U, Th ,or Ra) on the basis of leaching experiments• Is increase in rate of entry of radionuclide wastes into liquidmatrixes indicated? Can it be modeled? Does it provide deeperd di f lid i l d d iunderstanding ofsolidmaterialdegradation processes?• Weathering processes from black shales from near surfaceexposures as analogues for deeper “gas” shales?NORM in produced waters:Analogue Studies,Characterization of Bedrock,Radionuclide occurrence, Geochemical factors, andwastes• Isotopic forensics for wastes – to study processes,i t d d f i ti iprecise measurements neededofvariationsinconcentrations and isotope ratios• Characterize and monitor changes in the alreadyproduced wastes: brines, pipe scale, sludges,salts.• Design leaching/degradation experiments basedgg pon information percieved from waste monitoringand analogue studiesTools for Analysis for Monitoring Radionuclides inToolsforAnalysisforMonitoringRadionuclidesinthe Solid Matrix• Auto-Radiography• Fission-Track Radiography• Scanning electron microscopy energy dispersive x-ray(SEM/EDX)Xb ti d tit i h i•-ray absorption near edge spectroscopy - monitoring changeinspeciation/atom coordination• -microfocused X-rayFluorescence(uSXRF)microfocused X()ray absorption near edge spectroscopy (uXANES) from focusedsynchrotron beam (Brookhaven National Lab; StanfordSynchrotron Radiation Lightsource)SynchrotronRadiationLightsource)• -Organic Molecular analysis of U-organo matrixLeaching/degradation experimentsDi ib i i lid b f d f l hi•Distributionin solidsbefore andafterleaching• Ongoing Isotopic monitoring of evolving liquidswith precise measurements• Possible ongoingsolids characterization duringg gleaching experiments? (using synchrotronlightsource))• Characterize organo-U complexesFission Track Autoradioagraphy (U fission stimulated & imaged)Despite high U in zircongrain, most U is ingrain coatingsg g g gShallow black shale. In places, U distributed evenly in matrix;surprising local reconcentration found in carbonate-replacedI li i f i l & ? (SEM/EDXzones.Implicationsfor mineralogy&transport?(SEM/EDX+ autoradiograph imagesAutoradiograph: Radionuclides redistributed in oxides in fracturesAdditional findings from analouge studiesAdditionalfindingsfromanalougestudies-Radionuclides concentrated alongressure solution frontspThese zones may be enhanced zones of fluids migration-Radionuclides associate with secondary minerals,i l di it If t d illi il di l i iincluding pyrite.Iftrue,drilling spoilsdisposalis anissue(acid drainage and radionuclide mobilization issues)Design of any process study (leaching?) experimentsneeds pre-existing information of distribution in solids;unlikely that the process behavior will be the same withrespect to various modes of occurrence in the solids