Engineering Commons^™

An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer

All Theses

Understanding how radionuclides interact in the subsurface is important for the remediation of contaminated sites, assessment of risk due to radioactive waste disposal, and designing new radioactive waste management strategies. The current understanding of the geochemical behavior of radionuclides in the subsurface and more specifically the vadose zone has been developed through reactive transport modeling supplemented by laboratory experiments. Interactions between radionuclides with the mineral particles and organic matter in the vadose zone can be very complex and while laboratory experiments produce valuable data, few controlled, intermediate scale transport studies have been performed. In order to accurately predict vadose zone …

The Use Of Oxidants For Ndma Precursor Deactivation In Wastewater Treatment, Jaclyn Lauer

All Theses

Water treatment plants in the United States (US) have been switching from chlorination to chloramination in the search for a disinfection process to reduce formation of regulated disinfection by-products (DBPs). Unfortunately, the trade-off is the formation of N-nitrosamines. N-nitrosodimethylamine (NDMA) is the most commonly detected N-nitrosamine in US distribution systems. In the Integrated Risk Information Service (IRIS) database of the United States Environmental Protection Agency (USEPA), NDMA has been identified to have an estimated 10-6 lifetime cancer risk level at a concentration of 0.7 ng/L in drinking water. N-nitrosamines are currently not regulated by the USEPA; however, are listed on …

Lab-Scale Experiment For Assessing The Effect Of Resuspension And Oxygenation On Sediment Oxygen Demand, Grace Richardson

Graduate Theses and Dissertations

This study examined the effects of resuspending lake sediment for different time periods in a lab-scale tank under both oxic and anoxic conditions on sediment oxygen demand (SOD) and other related sediment properties. This lab-scale study was conducted as a first step to determine if a proposed method for reducing SOD by treating sediments in lakes and reservoirs is feasible. SOD is a critical process responsible for the formation of anoxic hypolimnia in lakes and reservoirs. A reduction in SOD may delay or eliminate the onset of anoxia in the hypolimnia, preventing adverse ecosystem effects and improving water quality and …

Adsorption Of Halogenated Aliphatic Contaminants By Graphene Nanomaterials: Comparison With Carbon Nanotubes And Granular Activated Carbons, Yang Zhou

All Theses

Graphene nanomaterials are two-dimensional single layer sp2 hybridized carbon atoms densely packed in a hexagonal honeycomb lattice and can be visualized as basic building blocks for fullerenes, carbon nanotubes (CNTs), and graphite. In addition, they are hydrophobic nanomaterials and possess a large specific surface area (SSA), thus they have been evaluated as promising adsorbents to remove synthetic organic compounds (SOCs) from water. As with granular activated carbons (GACs) and CNTs, adsorption behavior of SOCs on graphene depends on the physicochemical properties of the adsorbents (e.g., specific surface area, pore size distribution and surface chemistry), SOCs (e.g., hydrophobicity, molecular size and …

Potential Effects Of Geologic Storage Of Co2 On Surface Water And Shallow Groundwater, Shuangshuang Xie

All Theses

ABSTRACT Storage of supercritical phase CO2 in deep saline aquifers is being considered to reduce greenhouse gases in the atmosphere, and this process is expected to increase the pressure in these deep aquifers. One potential consequence of pressurization is an increase in the upward flux of saline water. Saline groundwater occurs naturally at shallow depths in many sedimentary basins, so an upward flux of solutes could degrade the quality of aquifers, and threaten aquatic ecosystems where groundwater discharge is important. The objective of this research is to evaluate the impacts associated with increasing the upward flux of saline water as …

Dendritic Polymers As Biocompatible Oil Spill Dispersants: Effectiveness And Mechanisims With Crude Oil, Ying Tu

All Theses

Dendritic polymers have recently been shown to entrap polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic materials. Laboratory results have shown that poly(amidoamine) dendrimers and hyperbranched poly(ethyleneimine) polymers form complexes with linear (hexadecane) and polyaromatic (phenanthrene) hydrocarbons, increasing the dispersion of these model crude oil components. It is thus hypothesized that crude oil can be dispersed using these polymers. Compared with commercial dispersants, dendritic polymers have the potential to be more biocompatible and less toxic. The objective of this research was to gain a fundamental understanding of the interactions of dendritic polymers with crude oil. We used Louisians Sweet Crude oil …

Ecohydrological Function Of Lower Coastal Plain Bioretention Cells In South Carolina, Jessica Palazzolo

All Theses

Flooding and stormwater control is a critical issue in coastal South Carolina because of shallow water table elevation, topography and rapid urbanization in the region. A best management practice (BMP) using low impact design (LID) principles known as a bioretention cell (BRC) is gaining popularity for stormwater management. Five BRCs in four landscape positions (well-drained uplands, tidal-proximal, poorly-drained-uplands, and floodplain) were instrumented for microclimate, soil moisture, and water table elevation for hydraulic efficiency and for water quality measurements. Three BRCs did not have an overflow outlets, one BRC (floodplain) employed an underdrain system, and one BRC (tidal proximal) had an …

Transport Properties Of Nano-Silica Contained Self-Consolidating Concrete, Borhan Moradi

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this research study, transport properties of various self-consolidating concretes (SCCs) containing nano-particles (SiO2) were investigated. Nano-silica replaced a portion of the cementitious materials at different replacement levels ranging from 1.5 to 7.5% by weight. For the purpose of this investigation, flow, bulk, and transport properties of SCCs were studied. The investigated transport properties were absorption, water penetration, rapid chloride permeability, capillary absorption, rapid migration, and chloride diffusion. Transport properties of nano-silica SCCs were also compared to those of equivalent silica fume (micro silica) contained concretes, as well as those of control mixture (concrete without nano or micro silica).

Test …

Mathematical Equations And System Identification Models For A Portable Pneumatic Bladder System Designed To Reduce Human Exposure To Whole Body Shock And Vibration, Ezzat Aziz Ayyad

UNLV Theses, Dissertations, Professional Papers, and Capstones

A mathematical representation is sought to model the behavior of a portable pneumatic foam bladder designed to mitigate the effects of human exposure to shock and whole body random vibration. Fluid Dynamics principles are used to derive the analytic differential equations used for the physical equations Model. Additionally, combination of Wiener and Hammerstein block oriented representation techniques have been selected to create system identification (SID) block oriented models. A number of algorithms have been iterated to obtain numerical solutions for the system of equations which was found to be coupled and non-linear, with no analytic closed form solution. The purpose …

Modeling That Leads To The Prediction Of Photocatalytic Coatings Characterization, Biju Bajracharya

Dissertations

One of the abundant sources of energy on earth is a solar energy which is the clean and safest energy source. It is also known as universal energy, the most important source of renewable energy available today. On realizing that the light source has a crucial role in daily life, several scientists and researchers from centuries ago have studied to establish photo induced systems and utilized them. Long after the knowledge of thermal energy, photovoltaic energy, and photosynthesis in plants, two prominent scientists, Fujishima and Honda, have discovered the electrochemical photolysis of water with the Titanium dioxide electrode which was …

Effects Of Natural Organic Matter On Contaminant Removal By Superfine Powdered Activated Carbon Coupled With Microfiltration Membranes, Mengfei Li

All Theses

Hybrid activated carbon/membrane systems are used in drinking water treatment for their significant capability of removing synthetic organic contaminants (SOCs) or taste-and-odor compounds along with particles. Preliminary data showed that decreasing the carbon particle size and creating superfine powdered activated carbon (S-PAC) removed phenanthrene and atrazine better than adsorbents with larger particle size in the presence of competitive adsorbents like natural organic matter (NOM). NOM is present in all natural water from degradation of terrestrial biomass which leaches from soil into a water source. Water treatment facilities target the removal of NOM because they are precursors to disinfection by-products formed …

Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

This study examines connections between mean sea level (MSL) variability and diurnal and semidiurnal tidal constituent variations at 17 open-ocean and 9 continental shelf tide gauges in the western tropical Pacific Ocean, a region showing anomalous rise in MSL over the last 20 years and strong interannual variability. Detrended MSL fluctuations are correlated with detrended tidal amplitude and phase fluctuations, defined as tidal anomaly trends (TATs), to quantify the response of tidal properties to MSL variation. About 20 significant amplitude and phase TATs are found for each of the two strongest tidal constituents, K₁ (diurnal) and M₂ (semidiurnal). …

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a …

Anaerobic And Aerobic Biodegradation Of The Oil Dispersant Components 1,2-Propanediol And 2-Butoxyethanol In Seawater, Benjamin Rhiner

All Theses

Oil spills are a recurring issue associated with fossil fuel consumption. The largest accidental oil spill in the history of the petroleum industry was the Deepwater Horizon explosion and seafloor well blowout, where the Deepwater Horizon oil rig exploded and sank, allowing the well to gush uncontrolled from April 20, 2010, until it was capped on July 15, 2010, releasing an estimated 210,000,000 gallons of oil. Oil dispersants were used in unprecedented quantities during the cleanup response to the spill with a total of 1,840,000 gallons of the dispersant COREXIT being applied. The goal of this research was to evaluate …

Assessment Of Nitrifying Bacteria In Massard Plant Using Molecular Tools, Jennifer Puanani Holmes-Smith

Civil Engineering Undergraduate Honors Theses

The discharge of nutrients (such as nitrogen and phosphorus) from wastewater treatment plants (WWTP) has become an increasingly important issue in the United States. Ammonia (NH3) is a common contaminant found in domestic wastewater and agricultural runoff. It can cause toxicity in fish if left untreated. The United States Environmental Protection Agency (EPA) recommends low national criteria for ammonia limits in freshwater. With these greater restrictions, ammonia-nitrogen limit compliance (5 mg/L) has become an issue at the Massard WWTP in Fort Smith, Arkansas. The purpose of this research is to assess the ammonia removal in the Massard WWTP in order …

Treatment Of Nitrogen Oxides By Chlorella Vulgaris Algae In Photobioreactors, Steven Shihady

Master's Theses

The effectiveness of algae to treat NO₂and NO in simulated flue gas was tested using Chlorella vulgaris in photobioreactors (PBRs) using NO_xconcentrations between 30 ppm to 780 ppm. NO_xdissolved and reacted in water to form NO₃^-and NO₂^-in the PBR growth medium, providing a nitrogen source that the algae readily assimilated for cell synthesis. Three 20-L photobioreactors were inoculated with a pure culture of C. vulgaris prepared in Bristol growth medium and algae were grown in the PBRs at 25°C and pH of 7.0 in a modified Bristol medium …

Predictive Model Development For Adsorption Of Organic Contaminants By Carbon Nanotubes, Onur Apul

All Dissertations

The main objective of the study was to investigate mechanisms and statistical modeling of synthetic organic contaminant (SOC) adsorption by carbon nanotubes (CNTs). First, predictive models were developed for adsorption of low molecular weight aromatic compounds by multi-walled carbon nanotubes (MWCNTs) using experimental data for 59 compounds. Quantitative structure-activity relationship (QSAR) and linear solvation energy relationship (LSER) approaches were employed and developed models were externally validated using an independent dataset obtained from the literature. Up to date, no QSAR model has been reported for predicting adsorption of organics by CNTs. No LSER model is available which comprehensively investigates the adsorption …

The Effects Of Amine Structure, Chloramine Species And Oxidation Strategies On The Formation Of N-Nitrosodimethylamine, Meric Selbes

All Dissertations

To comply with the increasingly stringent disinfection by-product (DBP) regulations in the United States, many water treatment plants have been switching from chlorination to chloramination in the last decade. Although chloramination reduces the formation of regulated DBPs such as trihalomethanes and haloacetic acids, it causes the formation of nitrosamines. Nitrosamines are a class of compounds that are probable human carcinogens, mutagens and teratogens at concentrations as low as 0.2 ng/L. In particular, N-nitrosodimethylamine (NDMA) is the most frequently detected nitrosamine in distribution systems in the United States. Although, nitrosamines are currently not regulated by the USEPA, they have been recently …

Informing Flood Plain Wetland Restoration Using Amphibian Monitoring, Ashley Vanderham

School of Natural Resources: Dissertations, Theses, and Student Research

Wetlands are among the most important and complex ecosystems in the world. They contribute to nutrient cycling, the hydrologic cycle, and provide critical habitat for many plants, fish, and wildlife. Channelization of Missouri River resulted in the loss of many floodplain wetlands. Despite ongoing restoration efforts, there are few ecologically-based performance guidelines, and managers need methods to quantify and assess the success of restored riverine wetland systems.

In 2008 a multi-institutional herpetofauna monitoring project, funded by the U.S. Army Corps of Engineers, was initiated in four states (Kansas, Missouri, Iowa, and Nebraska). The main goal of the project is to …

Emission Of Volatile Organic Compounds After Land Application Of Cattle Manure, Bryan Woodbury, John E. Gilley, David B. Parker, David B. Marx, Daniel N. Miller, Roger A. Eigenberg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Beef cattle manure can serve as a valuable source of nutrients for crop production. However, emissions of volatile organic compounds (VOCs) after land application may pose an odor nuisance to downwind populations. This study was conducted to evaluate the effects of land application method, diet, soil moisture content, and time since manure application on VOC emissions. Manure was collected from feedlot pens where cattle were fed diets containing 0, 10, or 30% wet distillers grains with solubles (WDGS). Land application methods included surface-applying manure (i.e., no-tillage) or incorporating manure using disk tillage. The effects of soil moisture content on VOC …

Opuntia Ficus-Indica Mucilage Potential To Remove Nuclear Active Contaminants From Water Based On A Surrogate Approach, Jose Adan Leon

USF Tampa Graduate Theses and Dissertations

Potable water is a necessity and unfortunately, it can be contaminated in many different ways. This paper specifically addresses the case scenario when, water has been contaminated by radionuclides. The mucilage of Opuntia ficus-indica (OFI), has been proven to be a great flocculating agent, turbidity reducer, crude oil dispersant and an environmentally friendly substance as an absorbent of water contaminants. In this work, the OFI mucilage was investigate to evaluate its capacity to separate radioactive ions from water. The surrogate approach is modeled based on water studies performed by Willi A. Brand, who proved that radioactive isotopes behave similar to …

Evaluation And Modeling Of Internal Water Storage Zone Performance In Denitrifying Bioretention Systems, Thomas Joseph Lynn

USF Tampa Graduate Theses and Dissertations

Nitrate (NO3) loadings from stormwater runoff promote eutrophication in surface waters. Low Impact Development (LID) is a type of best management practice aimed at restoring the hydrologic function of watersheds and removing contaminants before they are discharged into ground and surface waters. Also known as rain gardens, a bioretention system is a LID technology that is capable of increasing infliltration, reducing runoff rates and removing pollutants. They can be planted with visually appealing vegetation, which plays a role in nutrient uptake. A modified bioretention system incorporates a submerged internal water storage zone (IWSZ) that includes an electron donor to support …

Sustainable Development Of Biogas Resources In East Africa Using Transdisciplinary Design Models, Christopher M. Limiac

Open Access Theses

Installation of anaerobic digestion systems in urban developing communities has the potential to address multiple problems related to energy and sanitation in a combined systems approach. Anaerobic digesters are used to generate a relatively clean and rich source of energy in the form of biogas to address energy poverty issues. The design resources available for anaerobic digestion projects must be improved to provide greater technical support and project transparency. In order to develop holistic solutions to grand challenges like energy poverty, engineers must be prepared to operate with the complexities of diverse environments. Globalization and the improvement of transdisciplinary project …

A Fesability Analysis Of A Novel Constructed Wetland Design Tool For Arusha, Tanzania, Michael R. Sheehan

Open Access Theses

While water is a resource necessary for all life, in Tanzania alone over 20 million people who live in rural areas have no access to improved water sources. Water stress is a major concern in rural Tanzania, where annual potential evaporation can outpace precipitation by hundreds of mm per year. There is a significant need for improved access to water sources for Tanzanians living in rural regions of Arusha. To improve access to water, both water quantity and quality need to be addressed in a treatment system. Various water collection and treatment systems were compared and contrasted through the lens …

Hydrologic Impacts Due To Land Cover Change In The Yellowwood Lake Watershed, Emily Maria Stewart

Open Access Theses

The Yellowwood Lake watershed in Southern Indiana has experienced land cover change due to forest harvest throughout the last century. A group of local stakeholders have identified sedimentation into the lake and surface erosion as major concerns for the watershed. The main objective of this study is to better understand how forest harvest methods applied within the watershed effect hydrologic and soil erosion processes. Such knowledge is required to develop a more comprehensive plan to protect the watershed. ^ The Distributed Hydrology-Soil-Vegetation Model (DHSVM) was used for this analysis. This is a physically based, distributed hydrology model that simulates the …

Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou

Open Access Theses

Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …

An Analysis Of Secular Change In Tides At Open-Ocean Sites In The Pacific, Edward D. Zaron, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Hourly sea level is examined at 25 open-ocean stations in the Pacific Ocean with records longer than 30 yr. A search for trends finds that the amplitude of the dominant semidiurnal tide M₂ is increasing at 12 of the 13 sites where a statistically significant trend can be identified. It is also found that nontidal variance in the neighborhood of M₂ is decreasing at all 12 of the sites where a significant increase in M₂ tide is occurring. The trend in amplitude of the dominant diurnal tide K₁ is significant at six stations, and it is …

Feasibility Of Mainstream Nitrite Oxidizing Bacteria Out-Selection And Anammox Polishing For Enhanced Nitrogen Removal, Pusker Raj Regmi

Civil & Environmental Engineering Theses & Dissertations

Short-cut nitrogen removal avoids nitrite oxidation to nitrate by nitrite oxidizing bacteria (NOB) and allows a) reduction of formed nitrite to nitrogen gas via heterotrophic denitrification and/or b) oxidation of remaining ammonia with formed nitrite to nitrogen gas via anaerobic ammonia oxidation (anammox). The precondition for achieving shortcut nitrogen removal is suppression of NOB, which is favored by warm and high ammonia strength conditions found in internally generated ammonia-rich waste streams through anaerobic digestion of waste solids referred to as sidestreams or reject water. The discovery of anammox bacteria in the mid-1990s, which are capable of transforming NH₄+ …

Evaluation Of The Epa Swmm Model To Simulate Low Impact Development Features In An Urban Stormwater Environment, Holly Ann Carpenter

Civil & Environmental Engineering Theses & Dissertations

This research thesis explores the use of the Environmental Protection Agency's (EPA) Stormwater Water Management Model (SWMM) to model an urban watershed with a developed stormwater management system and test the SWMM model's ability to simulate Low Impact Development (LID) features by proposing typical LID features that can be retrofitted to the developed study area. The SWMM model is established with an existing survey of the study area's stormwater management system, and due to the lack of field data for the study area, the model developed in this research thesis is calibrated with the consideration of a published stormwater model …

Study Of Process Control Strategies For Biological Nutrient Removal In An Oxidation Ditch, Leslie Ann Knapp

USF Tampa Graduate Theses and Dissertations

Advanced wastewater treatment plants must meet permit requirements for organics, solids, nutrients and indicator bacteria, while striving to do so in a cost effective manner. This requires meeting day-to-day fluctuations in climate, influent flows and pollutant loads as well as equipment availability with appropriate and effective process control measures. A study was carried out to assess performance and process control strategies at the Falkenburg Road Advanced Wastewater Treatment Plant in Hillsborough County, Florida.

Three main areas for control of the wastewater treatment process are aeration, return and waste sludge flows, and addition of chemicals. The Falkenburg AWWTP uses oxidation ditches …