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Full-Text Articles in Engineering

Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa Dec 2008

Dechlorinating And Iron Reducing Bacteria Distribution In A Trichloroethene Contaminated Aquifer, Carmen Lourdes Yupanqui Zaa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Operable Unit 5 (OU 5) area of Hill Air Force Base currently has two trichloroethene-contaminated groundwater plumes underneath residential areas in Sunset and Clinton, Utah. Bioremediation by biological reductive dechlorination can be an important mechanism for the removal of chlorinated compounds from the plumes. The presence of suitable bacteria to carry on reductive dechlorination is the key in the bioremediation process. The goal of this study was to determine the distribution and population density of the 16S rRNA genes of Bacteria, Dehalococcoides ethenogenes, Desulfuromonas michiganensis, Geobacter spp and Rhodoferax ferrireducens-like bacteria, as well as the functional genes trichloroethene reductive …


Rank-Data Distribution Method (R-D Method) For Daily Time-Series Bayesian Networks And Total Maximum Daily Load Estimation, Joon-Hee Lee Dec 2008

Rank-Data Distribution Method (R-D Method) For Daily Time-Series Bayesian Networks And Total Maximum Daily Load Estimation, Joon-Hee Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Daily time series-based models are required to estimate the higher frequency fluctuations of nutrient loads and concentrations. Some mechanistic mathematical models can provide daily time series outputs of nutrient concentrations but it is difficult to incorporate non-numerical data, such as management scenarios, to mechanistic mathematical models. Bayesian networks (BNs) were designed to accept and process inputs of varied types of both numerical and non-numerical inputs.

A Rank-Data distribution method (R-D method) was developed to provide large time series of daily predicted flows and Total Phosphorus (TP) loads to BNs driving daily time series estimates of T-P concentrations into Hyrum and …


Estimating Total Phosphorus And Total Suspended Solids Loads From High Frequency Data, Amber Spackman Jones Dec 2008

Estimating Total Phosphorus And Total Suspended Solids Loads From High Frequency Data, Amber Spackman Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Frequently measured turbidity was examined as a surrogate for total phosphorus (TP) and total suspended solids (TSS) loads at two locations in the Little Bear River, Utah, USA. Using regression techniques, equations were developed for TP and TSS as functions of turbidity. The equations accounted for censored data, and additional explanatory variables to represent hydrological conditions were considered for inclusion in the equations. By using the resulting surrogate relationships with high frequency turbidity measurements, high frequency estimates of TP and TSS concentrations were calculated. To examine the effect of sampling frequency, reference loads were determined from the concentration records for …


Hydrogen Production By Anaerobic Fermentation Using Agricultural And Food Processing Wastes Utilizing A Two-Stage Digestion System, Reese S. Thompson Dec 2008

Hydrogen Production By Anaerobic Fermentation Using Agricultural And Food Processing Wastes Utilizing A Two-Stage Digestion System, Reese S. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hydrogen production by means of anaerobic fermentation was researched utilizing three different substrates. Synthetic wastewater, dairy manure, and cheese whey were combined together at different concentrations under batch anaerobic conditions to determine the optimal hydrogen producing potential and waste treatment of each. Cheese whey at a concentration of 55% was combined with dairy manure at a concentration of 45% to produce 1.53 liters of hydrogen per liter of substrate. These results are significant because the control, synthetic wastewater, which was a glucose-based substrate, produced less hydrogen, 1.34 liters per liter of substrate, than the mixture of cheese whey and dairy …


Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones Dec 2008

Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the continued population growth and the blurring of the urban and rural interface, air quality impacts associated with agricultural particle-producing processes are becoming increasingly important. There is a lack of emission rate data from these source types and no prescribed measurement technique available to the agricultural and regulatory communities. One technique that has shown promise is combining field measurements with inverse modeling. This approach was used herein to examine particulate emissions from an almond harvesting operation, a cotton ginning facility, and comparative emissions from conservation versus conventional tillage practices. EPAapproved models ISCST3 and AERMOD were used with AirMetrics samplers. …


Uptake And Release Kinetics Of Sulfolane By Cattail Plants, Tiffany Leo Dec 2008

Uptake And Release Kinetics Of Sulfolane By Cattail Plants, Tiffany Leo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sulfolane (tetrahydrothiophene 1,1-dioxide, C4H8O2S) is a highly water-soluble, non-ionizable, organic compound used along with diisopropanolamine in the Sulfinol™️ process to remove hydrogen sulfide from natural gas. Sulfolane has been identified in wetland vegetation near a sour gas processing facility in Alberta, Canada, and extensive uptake of sulfolane by cattails has also been demonstrated in a laboratory environment. Consequently, it has been suggested that plants could play an important role in the natural attenuation of sulfolane in contaminated wetlands. This assumes that the sulfolane is metabolized and/or sequestered in the plant and not released back …


Identification Of Chlorinated Solvent Sources In The Indoor Air Of Private Residences Around Hill Air Force Base, Utah, Andrew Jensen Hall Dec 2008

Identification Of Chlorinated Solvent Sources In The Indoor Air Of Private Residences Around Hill Air Force Base, Utah, Andrew Jensen Hall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Volatile chlorinated solvents such as trichloroethylene (TCE), 1,2 dichloroethane (1,2 DCA), and perchloroethylene (PCE) have been identified in the indoor air of residences located near Hill Air Force Base (AFB), Utah. These vapors can originate from either volatilization of contaminates from shallow contaminated groundwater and transport into residences or from sources within the residence. The focus of the thesis was the development of a testing strategy for determining sources of TCE, 1,2 DCA, and PCE in the indoor air of residences near Hill AFB.

Eight residences were selected for this study by Hill AFB based on prior detections of TCE, …


Volatilization Of Trichloroethylene From Shallow Subsurface Environments: Trees And Soil, Rachel Melanie Winters Dec 2008

Volatilization Of Trichloroethylene From Shallow Subsurface Environments: Trees And Soil, Rachel Melanie Winters

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Results from two previous studies conducted at Operable Unit 2 (OU2) of Hill Air Force Base, Utah indicate that the phytovolatilization (volatilization from leaves and trunk) of TCE by indigenous trees as well as soil surface flux may play a significant role in the removal of TCE from shallow groundwater plumes around the base. Previous studies investigated late summer and early autumn TCE leaf volatilization but no attempt was made to examine potential TCE volatilization seasonal variability and the volatilization of TCE directly from tree trunks. Whole tree transpiration rates were also not directly measured. To address those limitations and …


Measuring And Modeling Of Plant Root Uptake Of Organic Chemicals, Erik Dettenmaier Dec 2008

Measuring And Modeling Of Plant Root Uptake Of Organic Chemicals, Erik Dettenmaier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining the root uptake of xenobiotic organic chemicals into plants is critical for assessing the human and ecological health risks associated with the consumption of plants growing in contaminated environments. Root uptake of xenobiotic organics occurs passively in conjunction with transpiration and the transport from root to shoot is ultimately controlled by passage through one or more lipid root membranes. The transpiration stream concentration factor (TSCF), the ratio between the concentration of a chemical in the xylem to that in the solution used by the roots, is used to describe the relative ability of an organic chemical to be passively …


The Influence Of Debris Cages On Critical Submergence Of Vertical Intakes In Reservoirs, Skyler D. Allen Dec 2008

The Influence Of Debris Cages On Critical Submergence Of Vertical Intakes In Reservoirs, Skyler D. Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study quantifies the influence of debris cages on critical submergence at vertical intakes in reservoir configurations. Four model debris cages were constructed of light panel material. A vertical intake protruding one pipe diameter above the floor of a model reservoir was tested in six configurations: open intake pipe, a debris grate placed directly over the intake pipe, and debris cages representing widths of 1.5*d and 2*d and heights of 1.5*c and 2*c, where d is diameter of the intake and c is height of intake above reservoir floor. A selection of top grating configurations and a submerged raft configuration …


Nutrient Mobility From Biosolids Land Application Sites, Mai Anh Vu Tran May 2008

Nutrient Mobility From Biosolids Land Application Sites, Mai Anh Vu Tran

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three types of biosolids (lime-stabilized, aerobically digested, and anaerobically digested biosolids) were applied on 0.13-ha test plots on disturbed rangelands in Western Utah at rates of up to twenty times (20X) the estimated N-based agronomic rate. Soil samples at depths up to 1.5 m were collected and analyzed for nitrogen, phosphorus, regulated metals, pH, and electrical conductivity for up to two years after biosolids application.

NH4-N at the soil surface (0.2 m) was primarily lost through ammonia volatilization and nitrification. This observation was consistent with reported increases in nitrate (NO3-N) concentrations found within the soil surface …


Algorithm Development Of The Aglite-Lidar Instrument, Christian Marchant May 2008

Algorithm Development Of The Aglite-Lidar Instrument, Christian Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particulate emissions from agricultural operations are increasingly receiving attention from regulatory bodies as a potential source of air pollution. The Space Dynamics Laboratory (SDL) has developed the Aglite system, a suite of instruments including a lidar that is capable of measuring particulate emission levels from agricultural facilities. This system provides a novel method of measuring particulate mass (PM) pollution, allowing measurements to be taken of diverse types of facilities with high temporal and spatial resolution. This high resolution allows for the measurement of emission levels generated by specific activities, fostering the development and determination of best management practices.

The Aglite …


Decision Analysis Considering Welfare Impacts In Water Resources Using The Benefit Transfer Approach, Ashraf Shaqadan May 2008

Decision Analysis Considering Welfare Impacts In Water Resources Using The Benefit Transfer Approach, Ashraf Shaqadan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Decision making in environmental management is faced with uncertainties associated with related environmental variables and processes. Decision makers are inclined to use resources to acquire better information in one or more uncertain variable(s). Typically, with limited resources available, characterizing the feasibility of such investment is desirable yet complicated.

In the context of reducing inherent uncertainty, decision makers need to tackle two difficult questions, first, the optimal selection of variable(s) and second, the optimal level of information collection which produces maximum gain in benefits.

We develop a new framework to assess the socioeconomic value of potential decisions of collecting additional information …