Theses and Dissertations at Montana State University (MSU)
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Item Swimming performance of Yellowstone cutthroat trout (Oncorhynchus virginalis bouvieri)(Montana State University - Bozeman, College of Engineering, 2024) Steele, Samuel William; Chairperson, Graduate Committee: Kathryn Plymesser; This is a manuscript style paper that includes co-authored chapters.Yellowstone Cutthroat Trout (Oncorhynchus virginalis bouvieri) inhabit the upper portions of the Yellowstone and Snake River basins of Montana, Wyoming, and Idaho. Although individual populations remain intact in headwater streams, anthropogenic activities have resulted in substantial declines in their historic range and core population abundance, and the classification as a species of concern in Montana. To aid in Yellowstone Cutthroat Trout restoration and conservation, we conducted two studies to characterize their swimming performance. In the first study, we used an open-channel flume to observe the volitional swimming performance of 168 hatchery-raised Yellowstone Cutthroat Trout, ranging in total length from 292 to 450 mm. Fish were tested against a range of water velocities (0.61, 0.94, 1.75, and 2.00 m .s -1) and temperatures (8.0 and 12.0°C). We observed that passage success decreased with increasing water velocities, ranging from 98% at 0.61 m .s -1 to 19% at 2.00 m .s -1, and that water temperature did not affect the maximum distance of ascent within each hydraulic challenge (? 2 ranged from 0.0 to 1.0, p-value > or = 0.3, df = 1). The overall maximum sprinting velocity was 4.59 m .s -1, mean maximum swimming velocity was 2.15 m .s -1, and average water velocity at gait transitions was 0.61 m .s -1 from sustained to prolonged, 0.94 m .s -1 from prolonged to unsteady burst glide, and <1.73 m .s-1 from unsteady burst glide to steady burst. In the second study, we quantified the U sprint swimming mode of Yellowstone Cutthroat Trout using a swim chamber. Sixty fish were individually tested, which resulted in a mean U sprint velocity of 3.91 body lengths .s -1 (SD = 0.56), equivalent to 1.48 m .s -1 (SD = 0.18). U sprint values ranged from 0.86 to 1.85 m .s -1 for Yellowstone Cutthroat Trout with total lengths of 314 mm to 456 mm. Gait transitions were observed from sustained-prolonged to burst-glide swim mode at a mean water velocity of 0.88 m .s -1 (SD = 0.15) and from burst-glide to strictly burst at 1.13 m .s -1 (SD = 0.18). These findings provide valuable information for assessing passage success probability and guiding the design of fish passage structures, which are essential for the restoration and conservation of native Yellowstone Cutthroat Trout populations.Item Removal of PFAS from synthetic wastewater using aerobic granular sludge(Montana State University - Bozeman, College of Engineering, 2023) Ritu, Tasnim Sultana; Co-chairs, Graduate Committee: Catherine KirklandThe project assesses the performance of the aerobic granular sludge (AGS) to remove poly- and per-fluoroalkyl substances (PFAS) and conventional nutrients like carbon, nitrogen, and phosphorus from synthetic wastewater in a sequencing batch reactor (SBR). AGS is an emerging wastewater treatment biofilm that may be effective in reducing the PFAS concentration in wastewater via sorption. PFAS are a class of man-made chemicals used as surfactants, fire retardants, and coating materials. PFAS compounds are very persistent in the environment and can lead to adverse health outcomes in humans. PFAS can migrate from consumer products and enter the influent of wastewater treatment plant (WWTP). PFAS compounds are poorly removed by conventional wastewater treatment methods making effluent from WWTP a significant source of PFAS in the environment. The project uses two specific PFAS which are perfluorooctanoic acid (PFOA) and perfluoro octane sulfonate acid (PFOS). Other objectives of this project are to monitor how PFAS influences the treatment of conventional wastewater constituents and the granules' structure and morphology. Two SBRs were started with floccular sludge from seed granules and continued for 402 days. Some standard laboratory analytical methods for nitrogen, phosphorus, and organic carbon were used to monitor the removal efficiencies of the granules. Solid phase extraction (SPE) and liquid chromatography with mass spectrometry (UPLC with ESI Q-TOF-MS) were used to assess the removal of PFOA and PFOS both from liquid and sludge phases. Maximum removal of 33% for PFOS and 28% for PFOA was achieved by AGS in the test SBR. PFOS/PFOA exposure affected the granule's physical properties, and the properties recovered within approximately 34 days of dosing. PFOS/PFOA contamination produced no significant effect on conventional nutrient removal except nitrification. Thus, the treatment of PFAS by AGS is economical, since AGS can treat several pollutants simultaneously in a single reactor. More research should be done on the disposal of PFAS-contaminated sludge and to increase the treatment efficiency.Item Assessing a novel approach to pharmaceutical removal from wastewater: aerobic granular sludge(Montana State University - Bozeman, College of Engineering, 2024) Bodle, Kylie Brigitta; Chairperson, Graduate Committee: Catherine Kirkland; This is a manuscript style paper that includes co-authored chapters.Pharmaceutical concentrations in various environmental matrices are increasing across the globe. Effluent discharge from wastewater treatment plants is a major vector by which pharmaceuticals enter the environment, as many of these compounds are not biodegradable under conventional wastewater treatment conditions. Although concentrations are currently low (ng/L to ?g/L levels), pharmaceutical contamination poses risks to both human and animal health, as many pharmaceuticals can have toxic effects on fish, birds, and small mammals, as well as contribute to the proliferation of antibiotic resistance genes in bacteria. Aerobic granular sludge (AGS), an emerging biofilm-based wastewater treatment biotechnology and the subject of this dissertation, may be capable of enhancing pharmaceutical removal from wastewater. Scientific literature indicates that AGS uses a mixture of both biodegradation and adsorption to remove pharmaceuticals, but thus far, studies on this topic are limited. The research detailed herein investigated how AGS was affected by a mixture of three common, but relatively unstudied, pharmaceuticals: diclofenac (anti-inflammatory), erythromycin (antibiotic), and gemfibrozil (lipid regulator). Studies described herein examined how AGS grown in two different environments--the lab versus a full-scale wastewater treatment plant--responded to pharmaceuticals. Pharmaceutical effects on wastewater treatment efficacy, active microbial populations, and biofilm structures were investigated. Pharmaceutical fates in both the aqueous and solid phases were also tracked. In general, lab-grown AGS was more negatively impacted by pharmaceutical exposure, evidenced by reduced wastewater treatment efficacy, declines in key wastewater-treating microbial populations, and reductions in biofilm lipid content. Pharmaceuticals were also poorly removed by lab-grown granules. In contrast, key microbial populations and biofilm structures remained stable throughout dosing in environmentally-grown AGS, and gemfibrozil was completely biodegraded. An important caveat to comparison of the two studies, however, is that the pharmaceutical dose to lab-grown AGS was approximately double that to environmental granules. Altogether, the research described herein demonstrates the promise of AGS as a dual wastewater and pharmaceutical treatment technology, but illustrates the importance of conducting experiments under conditions as environmentally relevant as possible.Item Underwater acoustic propagation modeling and utilization for marine hydrokinetic devices(Montana State University - Bozeman, College of Engineering, 2024) Hafla, Erin Christine; Chairperson, Graduate Committee: Erick JohnsonOver the last two decades, there has been growing concern surrounding the increase in underwater anthropogenic sounds as expanding human populations interact with marine life and look for alternative energy production methods. That concern has led to a significant push worldwide to understand how propagated sound interacts with the surrounding marine environment. Marine hydrokinetic (MHK) devices are an alternative source of renewable energy available, which generate electricity from the motion of tidal and ocean currents, as well as ocean waves. Sounds produced by MHKs tend to overlap the frequency range common to both marine fauna communication and behavior. Preliminary measurements indicate that sound level values fall near the total sound decibel limitations presented by regulatory bodies. To date, the power optimization of MHK arrays has been prioritized over how its sound is produced, directed, and may impact the marine soundscape. There is a gap in knowledge regarding how marine fauna may respond to these sounds and what their physical and behavioral impact may be, and an absence in measured levels from insitu MHK deployments. A model for predicting the propagation of sound from an array of MHK sources in a real environment is essential for understanding potential impacts on a surrounding system. This work presents a fully three-dimensional solution to a set of coupled, linearized velocity-pressure equations in the time-domain as applied to underwater systems, and is an alternative sound propagation model to the Helmholtz and wave equation methods. The model is validated for a single source located within a series of increasingly complex two-dimensional and three-dimensional shallow water environments and compared against analytical solutions, examples from literature, and recorded sound pressure levels collected from Sequim Bay, WA. An uncertainty analysis for an array of MHK devices is presented to further understand how multiple turbine signals interact with one another in increasingly complex systems. This research presents a novel use of the velocity-pressure equations to analyze the variability associated with sound sources as sound propagates through a selected environment to inform the design and deployment of a MHK device or array of devices to minimize potential future impacts.Item Use of geothermal bridge deck deicing systems to mitigate concrete deterioration in Montana(Montana State University - Bozeman, College of Engineering, 2023) Turner, Ethan Joseph; Co-chairs, Graduate Committee: Kirsten Matteson and Mohammad KhosraviReinforced concrete bridge decks face deterioration from thermal stresses, frost action, and early-age cracking. This thesis presents experimental testing and numerical simulations on a bridge deck deicing system's ability to mitigate concrete deterioration. Two experimental bridge deck models were constructed with embedded heat exchanger tubing and instrumented with thermocouples and strain gauges. The models were tested in a cold chamber laboratory under conditions representative of Montana winter weather. The experimental results suggested that a bridge deck deicing system with an inlet temperature of 8 °C shows promise in deicing, reducing thermal movements, and mitigating early-age cracking through thermal shrinkage. The temperature and strain results of the experiment were used to validate a numerical model constructed in COMSOL Multiphysics. Inlet fluid temperatures of 10 °C and 50 °C, chosen from common ground temperatures in Montana, were tested to evaluate the system's effect on frost action and thermal stresses. With a 10 °C inlet fluid temperature, the system showed promise in deicing and mitigating concrete deterioration. While the system did not always raise the surface temperature above 0 °C, the consistent increase in temperature suggested that under certain weather conditions, the system could keep the top surface temperature above 0 °C for a longer period than with no system. The system was also successful in reducing the range of strain due to thermal movements. The system was not able to mitigate the effects of frost action or temperature gradients. The temperature gradients induced by the system were at times worse than without the system, but the difference was insignificant. With a 50 °C fluid temperature, the system was more effective in deicing and mitigating frost action. The range of strain from thermal movements was also reduced more than with a 10 °C inlet fluid temperature. The thermal gradients, however, were at times slightly greater than design gradients provided by design specifications. The excessive gradients, however, only occurred during extreme weather conditions that are less common in Montana. While not perfect, geothermal bridge deck deicing systems show promise for mitigating some mechanisms of concrete deterioration, while keeping other mechanisms within allowable limits.Item Numerical simulation of rock ramp fishway for small-bodied Great Plains fishes(Montana State University - Bozeman, College of Engineering, 2023) Ufelle, Cindy Chidumebi; Chairperson, Graduate Committee: Kathryn PlymesserThe preservation and restoration of fish populations and their habitats have become significant aspects of environmental conservation efforts. Effectiveness of fish passage structures plays a crucial role in facilitating the successful migration of various fish species. This research focused on utilizing Computational Fluid Dynamics (CFD) models to assess the hydraulic conditions within a rock ramp fishway with varying slopes and flow rates for small-bodied Great Plains fishes. This work built upon a previous study conducted by Swarr (2018) to investigate the passage success rates of three small-bodied fish of the Great Plains of North America: Flathead Chub (Platygobio gracilis), Arkansas Darter (Etheostoma cragini), and Stonecat (Noturus flavus) within a full-scale laboratory rock ramp fishway. Using commercial software, Flow-3D Hydro, CFD models were developed to simulate and predict hydraulic parameters such as flow depths, velocities, and turbulence kinetic energies (TKEs) within the fishway. To validate the accuracy of the CFD models, predicted flow depths and velocities were compared with observed data for two slopes: 2% and 10%. The CFD model results indicated that increasing slopes and flow rates led to corresponding increases in the mean values of the studied parameters. The mean depth varied from 0.051 m on the 2% slope to 0.068 m on the 10% slope. The mean velocity increased from 0.272 m/s on the mildest slope to 1.003 m/s on the steepest slope. Additionally, the average TKE ranged from 0.003 J/kg on the 2% slope to 0.014 J/kg on the 10% slope. The study highlighted that higher velocity and TKE values at steeper slopes may have contributed to the poor upstream passage rate, particularly for weaker swimmer species, like the Arkansas Darter, at slopes greater than 4%, as observed in the physical model study. Findings demonstrated that the presence of rocks in the fishway created diverse flow conditions. Low-velocity zones observed behind rocks within the fishway may provide favorable conditions for successful fish ascent. This research showcases the capabilities of CFD in providing quantitative data for optimizing fish passage structure design and contributing to conservation efforts.Item Concrete-filled steel tube to concrete pile cap connections: verification of analysis/design methodologies(Montana State University - Bozeman, College of Engineering, 2023) Cota, Cash Daniel; Chairperson, Graduate Committee: Michael BerryThis research project focuses on the structural behavior of concrete-filled steel tube (CFST) to concrete pile cap connections, a critical component in many Montana bridges. A series of four experimental pile cap connection specimens were designed and tested to assess the influence of key parameters such as specimen scale, concrete strength, and the incorporation of U-bars on the overall connection performance. The findings from this research revealed that all specimens, barring the specimen with U-bars, displayed consistent moment-drift responses, damage progression, and failure mechanisms within the concrete cap. The inclusion of U-bars notably increased the connection capacity by about 60%, altering the failure mechanism to a plastic hinge formation in the CFST pile. Additionally, the study validated the efficacy of a novel moment-rotation methodology for predicting the capacity of cap connections, with an average measured-to-predicted ratio of 0.95 and a coefficient of variation of 10%. However, this methodology showed a tendency to overpredict capacities in connections without U-bars and underpredict in those with U-bars. Overall, this research provides valuable insight into the behavior of these critical connections under diverse conditions and demonstrates the efficacy of the moment-rotation methodology.Item Comparing the mechanical properties of shale cores: intact vs. fractured and sealed with UICP(Montana State University - Bozeman, College of Engineering, 2023) Bedey, Kayla Marjorie; Chairperson, Graduate Committee: Catherine Kirkland; This is a manuscript style paper that includes co-authored chapters.Fractures in subsurface shale formations are instrumental in the recovery of hydrocarbon resources. A result of hydraulic fracturing, these fractures have the potential to become harmful leakage pathways that may contribute undesired fluids to the atmosphere and functional groundwater aquifers. Ureolysis-induced calcium carbonate precipitation (UICP) is a biomineral solution where the urease enzyme converts urea and calcium into calcium carbonate mineral. The resulting biomineral can bridge gaps in fractured shale, reduce undesired fluid flow through leakage pathways, limit fracture propagation, better store carbon dioxide, and potentially extend the efficiency of future and existing wells. The mechanical properties of fractured shale sealed with UICP was investigated using a modified Brazilian indirect tensile strength test. Part one of this study investigated the tensile strength of shale rock using intact Eagle Ford (EF) and Wolfcamp (WC) shale cores (5.08 cm long by 2.54 cm diameter) tested at room temperature (RT) and 60°C. Results show no significant difference between shale types (average tensile strength = 6.19 MPa). EF cores displayed a higher strength at RT versus 60°C, but no difference was seen between temperatures for WC cores. Part two used UICP to seal shale cores (5.08 cm long by 2.54 cm diameter) with a single, heterogeneous fracture spanning the core length. UICP was delivered two ways: 1) the flow-through method injected 20-30 sequential patterns of microbes and UICP-promoting fluids into the fracture until fracture permeability reduced by three orders of magnitude and 2) the immersion method placed cores treated with guar gum and UICP-promoting solutions into a batch reactor, demonstrating that guar gum is a suitable inclusion to UICP-technology and may be capable of reducing the number of injections required in flow-through methodology. Tensile results for both flow-through and immersion methods were widely variable (0.15 - 8 MPa), and in some cores the biomineralized fracture split apart. Notably in other cores the biomineralized fracture remained intact, demonstrating more cohesion than the surrounding shale, indicating that UICP may produce a strong seal for subsurface application.Item Investigation of microbially induced carbonate precipitation for mitigation of acid mine drainage from coal mining waste(Montana State University - Bozeman, College of Engineering, 2023) Delwiche, Jenna Anne; Chairperson, Graduate Committee: Ellen G. Lauchnor; Adrienne J. Phillips (co-chair); This is a manuscript style paper that includes co-authored chapters.Acid Mine Drainage (AMD) is a serious environmental concern associated with coal mining. Many of the existing methods for addressing AMD are costly and focus on clean-up rather than prevention. In this study, the feasibility of using microbially induced carbonate precipitation (MICP) as an alternative method for mitigating environmental impacts from coal mining waste rock was investigated using laboratory scale experiments. Flow-through column testing showed that MICP can be used to create a calcium carbonate coating on coal waste rock, acting as a barrier between the rock and water. This treatment increased leachate pH, and microscopic inspection indicated that the presence of live bacteria was important for creating a durable coating. The MICP treatment decreased concentrations of heavy metals such as aluminum, barium, beryllium, copper, nickel, zinc, and iron in the leachate, but increased concentrations of vanadium, selenium, molybdenum, uranium, and arsenic. These results indicate that MICP may be an effective technique for mitigating AMD, but additional laboratory and field testing is needed to assess the feasibility of this treatment technology.Item Feasibility study for field-scale use of Ureolysis-Induced Calcite Precipitation (UICP) for roadbed improvement(Montana State University - Bozeman, College of Engineering, 2023) Dorian, Hudson Thomas; Chairperson, Graduate Committee: Mohammad Khosravi; Adrienne J. Phillips (co-chair); This is a manuscript style paper that includes co-authored chapters.A series of tests were conducted to evaluate the feasibility of using ureolysis-induced calcium carbonate precipitation (UICP) to improve the strength of the soil layers used to in the construction of roads. This process involved three series of tests conducted on soil specimens of gradually increasing volume. The first series regarded the relative effect of treatment direction, comparing top-down treatment to bottom-upwards and alternating treatment methods on 50-by-100-millimeter soil columns. This was evaluated through unconfined compressive strength (UCS) and the calcium carbonate distribution over the length of the soil, finding that all methods generated a reliable increase in the strength of the soil specimen. This phase of research also included a batch study, evaluating the growth of the ureolytic bacteria Sporosarcina pasteurii in a solution composed of commercially available ingredients, showing that the bacteria could be cultured at a far lower cost (as low as 20 cents per liter) than with lab-grade ingredients ($2.66 per liter). The next series of tests compared the effect of applying treatment solutions to the soil surface directly and using a probe to inject solutions beneath the surface. This was done with 15-centimeter, cylindrical specimens, evaluated through the California bearing ratio (CBR) test. It was determined that the treatment process had the capacity to increase the CBR value substantially (from ~11% up to 188%), and it was suggested that each treatment mechanism resulted in a predictable distribution of calcium carbonate. There was also success in using alternative, commercially-sourced ingredients to facilitate the treatment and improve the CBR value. The last tests centered on the treatment of a 30-centimeter-by-30-centimeter mock road section, combining the treatment mechanisms used at the 15-centimeter-scale to facilitate an increase in the CBR of a soil layer under pavement. Through UICP, the CBR value of this layer was successfully increased.
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