Browsing by Author "Cunningham, Alfred B."
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Item Abandoned well CO2 leakage mitigation using biologically induced mineralization: Current progress and future directions(2013-02) Cunningham, Alfred B.Methods of mitigating leakage or re-plugging abandoned wells before exposure to CO2are of high potential interest to prevent leakage of CO2 injected for geologic carbon sequestration in depleted oil and gas reservoirs where large numbers of abandoned wells are often present. While CO2resistant cements and ultrafine cements are being developed, technologies that can be delivered via low viscosity fluids could have significant advantages including the ability to plug small aperture leaks such as fractures or delamination interfaces. Additionally there is the potential to plug rock formation pore space around the wellbore in particularly problematic situations. We are carrying out research on the use of microbial biofilms capable of inducing the precipitation of crystalline calcium carbonate using the process of ureolysis. This method has the potential to reduce well bore permeability, coat cement to reduce CO2–related corrosion, and lower the risk of unwanted upward CO2 migration. In this spotlight, we highlight research currently underway at the Center for Biofilm Engineering (CBE) at Montana State University (MSU) in the area of ureolytic biomineralization sealing for reducing CO2 leakage risk. This research program combines two novel core testing systems and a 3-dimensional simulation model to investigate biomineralization under both radial and axial flow conditions and at temperatures and pressures which permit CO2 to exist in the supercritical state.This combination of modeling and experimentation is ultimately aimed at developing and verifying biomineralization sealing technologies and strategies which can successfully be applied at the field scale for carbon capture and geological storage (CCGS) projects.Item Addressing wellbore integrity and thief zone permeability using microbially-induced calcium carbonate precipitation (MICP): A field demonstration(Elsevier BV, 2020-02) Kirkland, Catherine M.; Thane, Abby; Hiebert, Randy; Hyatt, Robert; Kirksey, Jim; Cunningham, Alfred B.; Gerlach, Robin; Spangler, Lee; Philips, Adrienne J.Microbially-induced calcium carbonate precipitation (MICP) is an emerging biotechnology for wellbore integrity applications including sealing defects in wellbore cement and modifying the permeability of rock formations. The goal of this field demonstration was to characterize a failed waterflood injection well and provide proof of principle that MICP can reduce permeability in the presence of oil using conventional oilfield fluid delivery methods. We compared well logs performed at the time the well was drilled with ultrasonic logs, sonic cement evaluation, and temperature logs conducted after the well failed. Analysis of these logs suggested that, rather than entering the target waterflood formation, injectate was traveling through defects in the well cement to a higher permeability sandstone layer above the target formation. Sporosarcina pasteurii cultures and urea-calcium media were delivered 2290 ft (698 m) below ground surface using a 3.75 gal (14.2 L) slickline dump bailer to promote mineralization in the undesired flow paths. By Day 6 and after 25 inoculum and 49 calcium media injections, the injectivity [gpm/psi] had decreased by approximately 70%. This demonstration shows that 1) common well logs can be used to identify scenarios where MICP can be employed to reduce system permeability, remediate leakage pathways, and improve waterflood efficiency, and 2) MICP can occur in the presence of hydrocarbons.Item Bacterial transport issues related to subsurface biobarriers(1999) Sharp, Robert R.; Gerlach, Robin; Cunningham, Alfred B.Item Bacterially induced calcium carbonate precipitation and strontium coprecipitation in a porous media flow system(2013-02) Lauchnor, Ellen G.; Schultz, Logan N.; Bugni, S.; Mitchell, Andrew C.; Cunningham, Alfred B.; Gerlach, RobinStrontium-90 is a principal radionuclide contaminant in the subsurface at several Department of Energy sites in the Western U.S., causing a threat to groundwater quality in areas such as Hanford, WA. In this work, we used laboratory-scale porous media flow cells to examine a potential remediation strategy employing coprecipitation of strontium in carbonate minerals. CaCO3 precipitation and strontium coprecipitation were induced via ureolysis by Sporosarcina pasteurii in two-dimensional porous media reactors. An injection strategy using pulsed injection of calcium mineralization medium was tested against a continuous injection strategy. The pulsed injection strategy involved periods of lowered calcite saturation index combined with short high fluid velocity flow periods of calcium mineralization medium followed by stagnation (no-flow) periods to promote homogeneous CaCO3 precipitation. By alternating the addition of mineralization and growth media the pulsed strategy promoted CaCO3 precipitation while sustaining the ureolytic culture over time. Both injection strategies achieved ureolysis with subsequent CaCO3 precipitation and strontium coprecipitation. The pulsed injection strategy precipitated 71−85% of calcium and 59% of strontium, while the continuous injection was less efficient and precipitated 61% of calcium and 56% of strontium. Over the 60-day operation of the pulsed reactors, ureolysis was continually observed, suggesting that the balance between growth and precipitation phases allowed for continued cell viability. Our results support the pulsed injection strategy as a viable option for ureolysis-induced strontium coprecipitation because it may reduce the likelihood of injection well accumulation caused by localized mineral plugging while Sr coprecipitation efficiency is maintained in field-scale applications.Item Bench-scale/field-scale interpretations: an overview(1995) Cunningham, Alfred B.Item Beyond the Surface: Non-Invasive Low-Field NMR Analysis of Microbially-Induced Calcium Carbonate Precipitation in Shale Fractures(Springer Science and Business Media LLC, 2024-07) Willett, Matthew R.; Bedey, Kayla; Crandall, Dustin; Seymour, Joseph D.; Rutqvist, Jonny; Cunningham, Alfred B.; Phillips, Adrienne J.; Kirkland, Catherine M.Microbially-induced calcium carbonate precipitation (MICP) is a biological process in which microbially-produced urease enzymes convert urea and calcium into solid calcium carbonate (CaCO3) deposits. MICP has been demonstrated to reduce permeability in shale fractures under elevated pressures, raising the possibility of applying this technology to enhance shale reservoir storage safety. For this and other applications to become a reality, non-invasive tools are needed to determine how effectively MICP seals shale fractures at subsurface temperatures. In this study, two different MICP strategies were tested on 2.54 cm diameter and 5.08 cm long shale cores with a single fracture at 60 ℃. Flow-through, pulsed-flow MICP-treatment was repeatedly applied to Marcellus shale fractures with and without sand (“proppant”) until reaching approximately four orders of magnitude reduction in apparent permeability, while a single application of polymer-based “immersion” MICP-treatment was applied to an Eagle Ford shale fracture with proppant. Low-field nuclear magnetic resonance (LF-NMR) and X-Ray computed microtomography (micro-CT) techniques were used to assess the degree of biomineralization. With the flow-through approach, these tools revealed that while CaCO3 precipitation occurred throughout the fracture, there was preferential precipitation around proppant. Without proppant, the same approach led to premature sealing at the inlet side of the core. In contrast, immersion MICP-treatment sealed off the fracture edges and showed less mineral precipitation overall. This study highlights the use of LF-NMR relaxometry in characterizing fracture sealing and can help guide NMR logging tools in subsurface remediation efforts.Item Beyond the Surface: Non-Invasive Low-Field NMR Analysis of Microbially-Induced Calcium Carbonate Precipitation in Shale Fractures(Springer Science and Business Media LLC, 2024-07) Willet, Matthew R.; Bedey, Kayla; Crandall, Dustin; Seymour, Joseph D.; Rutqvist, Jonny; Cunningham, Alfred B.; Phillips, Adrienne J.; Kirkland, Catherine M.Microbially-induced calcium carbonate precipitation (MICP) is a biological process in which microbially-produced urease enzymes convert urea and calcium into solid calcium carbonate (CaCO3) deposits. MICP has been demonstrated to reduce permeability in shale fractures under elevated pressures, raising the possibility of applying this technology to enhance shale reservoir storage safety. For this and other applications to become a reality, non-invasive tools are needed to determine how effectively MICP seals shale fractures at subsurface temperatures. In this study, two different MICP strategies were tested on 2.54 cm diameter and 5.08 cm long shale cores with a single fracture at 60 ℃. Flow-through, pulsed-flow MICP-treatment was repeatedly applied to Marcellus shale fractures with and without sand (“proppant”) until reaching approximately four orders of magnitude reduction in apparent permeability, while a single application of polymer-based “immersion” MICP-treatment was applied to an Eagle Ford shale fracture with proppant. Low-field nuclear magnetic resonance (LF-NMR) and X-Ray computed microtomography (micro-CT) techniques were used to assess the degree of biomineralization. With the flow-through approach, these tools revealed that while CaCO3 precipitation occurred throughout the fracture, there was preferential precipitation around proppant. Without proppant, the same approach led to premature sealing at the inlet side of the core. In contrast, immersion MICP-treatment sealed off the fracture edges and showed less mineral precipitation overall. This study highlights the use of LF-NMR relaxometry in characterizing fracture sealing and can help guide NMR logging tools in subsurface remediation efforts.Item Biofilm barriers to contain and degrade dissolved trichloroethylene(2004-04) Komlos, John; Cunningham, Alfred B.; Camper, Anne K.; Sharp, Robert R.Biologically produced subsurface barriers (i.e., biofilm barriers) are a viable technology for controlling contaminant migration from hazardous waste sites. Biofilm barriers are created through the injection of bacteria and selective growth medium into a series of wells downstream of a contaminant plume. Adequate substrate addition enables the bacteria to grow and form thick biofilms capable of uniform plugging of the subsurface. This technology has been successful in significantly reducing porous media permeability in bench-scale and field-scale applications. The research presented herein expands on current biofilm. barrier technology by examining the feasibility of using a biofilm barrier to not only control contaminant migration through permeability reduction, but also facilitate contaminant biodegradation. ne experimental scenario involved the creation of a dual-species biofilm matrix: one organism to reduce porous media permeability through thick biofilm formation and another organism to degrade a contaminant, in this case trichloroethylene (TCE). Porous medium column experiments demonstrated that a dual-species biofilm barrier can be created and that growth medium concentration was a very important variable in controlling simultaneous TCE degradation and permeability reduction.Item Biofilm enhanced subsurface sequestration of supercritical CO2(2009-01) Mitchell, Andrew C.; Phillips, Adrienne J.; Hiebert, Dwight Randall; Gerlach, Robin; Cunningham, Alfred B.In order to develop subsurface CO2 storage as a viable engineered mechanism to reduce the emission of CO2 into the atmosphere, any potential leakage of injected supercritical CO2 (SC-CO2) from the deep subsurface to the atmosphere must be reduced. Here, we investigate the utility of biofilms, which are microorganism assemblages firmly attached to a surface, as a means of reducing the permeability of deep subsurface porous geological matrices under high pressure and in the presence of SC-CO2, using a unique high pressure (8.9 MPa), moderate temperature (32 °C) flow reactor containing 40 millidarcy Berea sandstone cores. The flow reactor containing the sandstone core was inoculated with the biofilm forming organism Shewanella fridgidimarina. Electron microscopy of the rock core revealed substantial biofilm growth and accumulation under high-pressure conditions in the rock pore space which caused >95% reduction in core permeability. Permeability increased only slightly in response to SC-CO2 challenges of up to 71 h and starvation for up to 363 h in length. Viable population assays of microorganisms in the effluent indicated survival of the cells following SC-CO2 challenges and starvation, although S. fridgidimarina was succeeded by Bacillus mojavensis and Citrobacter sp. which were native in the core. These observations suggest that engineered biofilm barriers may be used to enhance the geologic sequestration of atmospheric CO2.Item Biofilm process in porous media - practical applications(1997) Cunningham, Alfred B.; Warwood, B. K.; Sturman, Paul J.; Horrigan, K.; James, Garth A.; Costerton, J. William; Hiebert, Dwight RandallItem Biofilm structure and influence on biofouling under laminar and turbulent flows(1999) Stoodley, Paul; Boyle, John D.; Cunningham, Alfred B.; Dodds, I.; Lappin-Scott, H. M.; Lewandowski, ZbigniewItem Biofilms in porous media(2000) Bouwer, Edward J.; Rijnaarts, Huub H. M.; Cunningham, Alfred B.; Gerlach, RobinItem Biogeochemical elimination of chromium (VI) contaminated water(2002-01) Nyman, Jennifer L.; Caccavo, Frank; Cunningham, Alfred B.; Gerlach, RobinFerrous iron [Fe(II)] reductively transforms heavy metals in contaminated groundwater, and the bacterial reduction of indigenous ferric iron [Fe(II)] has been proposed as a means of establishing redox reactive barriers in the subsurface. The reduction of Fe(III) to Fe(II) can be accomplished by stimulation of microbially produced Fe(II) can chemically react with contaminants such as Cr(VI) to form insoluble Cr(III) precipitates. The DMRB Shewanella algae BrY reduced highly soluble Cr(VI) to insoluble Cr(III). Once the chemical Cr(VI) reduction capacity of the Fe(II)/Fe(III) couple in the experimental systems was exhausted, the addition of S. algae BrY allowed for the repeated reduction of Fe(III) to Fe(II), which again reduced Cr(VI) to Cr(III). The research presented herein indicates that a biological process using DMRB allows the establishment of biogeochemical cycle that facilitates chromium production. Such a system could provide a means for establishing and maintaining remedial redox reactive zones on Fe(III)- bearing subsurface environments.Item Bulk electric conductivity response to soil and rock CO2 concentration during controlled CO2 release experiments: Observations & analytic modeling(2015-09) Jewell, Scott; Zhou, Xiaobing; Apple, Martha E.; Dobeck, Laura M.; Spangler, Lee H.; Cunningham, Alfred B.To develop monitoring technologies for geologic CO2 storage, controlled CO2 release experiments at the Zero Emissions Research and Technology (ZERT) site in Bozeman, Montana, USA, were carried out in 2009-2011. To understand the impact on the electric properties of soil and sediment rock due to possible CO2 leakage, we have developed an analytical model to explain and predict the electric conductivity (EC) for CO2 impacted soil and sedimentary rock. Results from the model were compared with the measurements at the ZERT site during 2009–2011 and the CO2-Vadose Project site in France in 2011-2012 after model calibration at each site. The model was calibrated using the saturation (n) and cementation (m) exponents contained in Archie's equation, and a chemistry coefficient (pKc) as tuning parameters that minimized the misfit between observed and modeled soil/rock bulk conductivity data. The calibration resulted in n=3.15, m=2.95, and pKc=4.7 for the ZERT site, which was within the range of values in the literature. All the ZERT data sets had rms errors of 0.0115-0.0724. For the CO2-Vadose site, calibration resulted in n=3.6-9.85 and m=2.5-4.2, pKc=4.80-5.65, and the rms error of 0.0002-0.0003; the cementation exponents were consistent with the literature. These results found that the model predicted the bulk EC reasonably well in soil and rock once the unmeasurable model parameters (n, m, and pKc) were calibrated.Item Changes in microbial communities and associated water and gas geochemistry across a sulfate gradient in coal beds: Powder River Basin, USA(2019-01) Schweitzer, Hannah D.; Ritter, Daniel J.; McIntosh, Jennifer C.; Barnhart, Elliott P.; Cunningham, Alfred B.; Vinson, David S.; Orem, William; Fields, Matthew W.Competition between microbial sulfate reduction and methanogenesis drives cycling of fossil carbon and generation of CH4 in sedimentary basins. However, little is understood about the fundamental relationship between subsurface aqueous geochemistry and microbiology that drives these processes. Here we relate elemental and isotopic geochemistry of coal-associated water and gas to the microbial community composition from wells in two different coal beds across CH4 and SO42− gradients (Powder River Basin, Montana, USA). Areas with high CH4 concentrations generally have higher alkalinity and δ13C-DIC values, little to no SO42−, and greater conversion of coal-biodegradable organics to CH4 (based on δ13C-CH4 and δ13C-CO2 values). Wells with SO42− concentrations from 2 to 10 mM had bacterial populations dominated by several different sulfate-reducing bacteria and archaea that were mostly novel and unclassified. In contrast, in wells with SO42− concentrations <1 mM, the sequences were dominated by presumptive syntrophic bacteria as well as archaeal Methanosarcinales and Methanomicrobiales. The presence of sequences indicative of these bacteria in low SO42− methanogenic wells may suggest a syntrophic role in coal biodegradation and/or the generation of methanogenic substrates from intermediate organic compounds. Archaeal sequences were observed in all sampled zones, with an enrichment of sequences indicative of methanogens in low SO42− zones and unclassified sequences in high SO42− zones. However, sequences indicative of Methanomassiliicoccales were enriched in intermediate SO42− zones and suggest tolerance to SO42− and/or alternative metabolisms in the presence of SO42−. Moreover, sequences indicative of methylotrophic methanogens were more prevalent in an intermediate SO42− and CH4 well and results suggest an important role for methylotrophic methanogens in critical zone transitions. The presented results demonstrate in situ changes in bacterial and archaeal population distributions along a SO42− gradient associated with recalcitrant, organic carbon that is biodegraded and converted to CO2 and/or CH4.Item Characterization of methyl tert-butyl ether-degrading bacteria from a gasoline-contaminated aquifer(2002-01) Kern, Eric Anthony; Veeh, Richard Harold; Macur, Richard E.; Cunningham, Alfred B.Molecular microbial community analysis was combined with traditional cultivation strategies to investigate the presence of methyl tert-butyl ether (MTBE)-degrading bacteria in a gasoline-contaminated aquifer (Ronan, MT). A bacterial consortium, RS24, which is capable of complete mineralization of MTBE as a sole carbon and energy source was enriched from soil and aquifer materials taken from the contaminated site. The consortium was capable of degrading MTBE at rates up to 0.66 mg d-,1 with corresponding gross biomass yields of 0.25 ± 0.02 mg dry biomass (mg MTBE)-1. Two MTBE-degrading isolates identified as Pseudomonas Ant9 and Rhodococcus koreensis were obtained from the consortium. However, both isolates required the presence of 2-propanol as a cosubstrate for MTBE degradation. Denaturing gradient gel electrophoresis (DGGE) of Polymerase Chain Reaction (PCR)-amplified 16S rDNA confirmed the presence of both isolates in the initial consortium and indicated their disappearance with transfer and subculturing. MTBE degradation and cell growth by the consortium was stimulated by the presence of spent culture medium, suggesting the production of a growth factor during MTBE degradation. These results indicate the presence of naturally occurring MTBE-degrading bacteria in a contaminated aquifer and suggest the potential for natural attenuation or enhanced aerobic oxidation.Item Chromium elimination with microbially reduced iron: redox-reactive biobarriers(1999) Gerlach, Robin; Cunningham, Alfred B.; Caccavo, FrankItem Cultivation of a native alga for biomass and biofuel accumulation in coal bed methane production water(2016-11) Hodgkiss, Logan H.; Nagy, J.; Barnhart, Elliott P.; Cunningham, Alfred B.; Fields, Matthew W.Coal bed methane (CBM) production has resulted in thousands of ponds in the Powder River Basin of low-quality water in a water-challenged region. A green alga isolate, PW95, was isolated from a CBM production pond, and analysis of a partial ribosomal gene sequence indicated the isolate belongs to the Chlorococcaceae family. Different combinations of macro- and micronutrients were evaluated for PW95 growth in CBM water compared to a defined medium. A small level of growth was observed in unamended CBM water (0.15 g/l), and biomass increased (2-fold) in amended CBM water or defined growth medium. The highest growth rate was observed in CBM water amended with both N and P, and the unamended CBM water displayed the lowest growth rate. The highest lipid content (27%) was observed in CBM water with nitrate, and a significant level of lipid accumulation was not observed in the defined growth medium. Growth analysis indicated that nitrate deprivation coincided with lipid accumulation in CBM production water, and lipid accumulation did not increase with additional phosphorus limitation. The presented results show that CBM production wastewater can be minimally amended and used for the cultivation of a native, lipid-accumulating alga.Item Darcy-scale modeling of microbially induced carbonate mineral precipitation in sand columns(2012-07) Ebigbo, Anozie; Phillips, Adrienne J.; Gerlach, Robin; Helmig, Rainer; Cunningham, Alfred B.; Class, Holger; Spangler, Lee H.This investigation focuses on the use of microbially induced calcium carbonate precipitation (MICP) to set up subsurface hydraulic barriers to potentially increase storage security near wellbores of CO2 storage sites. A numerical model is developed, capable of accounting for carbonate precipitation due to ureolytic bacterial activity as well as the flow of two fluid phases in the subsurface. The model is compared to experiments involving saturated flow through sand-packed columns to understand and optimize the processes involved as well as to validate the numerical model. It is then used to predict the effect of dense-phase CO2 and CO2-saturated water on carbonate precipitates in a porous medium.Item Degradation of xenobiotic compounds in situ: capabilities and limits(1994-10) Bouwer, Edward J.; Durant, N.; Wilson, L.; Zhang, Weiyan; Cunningham, Alfred B.Exploiting microorganisms for remediation of waste sites is a promising alternative to groundwater pumping and above ground treatment. The objective of in situ bioremediation is to stimulate the growth of indigenous or introduced microorganisms in regions of subsurface contamination, and thus to provide direct contact between microorganisms and the dissolved and sorbed contaminants for biotransformation. Subsurface microorganisms detected at a former manufactured gas plant site contaminated with coal tars mineralized significant amounts of naphthalene (8–43%) and phenanthrene (3–31%) in sediment-water microcosms incubated for 4 weeks under aerobic conditions. Evidence was obtained for naphthalene mineralization (8–13%) in the absence of oxygen in field samples. These data suggest that biodegradation of these compounds is occurring at the site, and the prospects are good for enhancing this biodegradation. Additional batch studies demonstrated that sorption of naphthalene onto aquifer materials reduced the extent and rate of biodegradation, indicating that desorption rate was controlling the biodegradation performance.