Engineering Commons^™

Modeling Distributed Source Control Infrastructure At Neighborhood Scale For Mitigating Flood Risk In Amite River Watershed, Ahmad Amin Shefai

LSU Master's Theses

Flooding has always been a major threat to mankind. This is particularly true in urban areas due to urbanization-induced increasing impervious areas and subsequent increasing urban surface runoff, causing an increasing flooding risk to urban areas in spite of the fact that extensive flood control infrastructure has been constructed. The overall goal of this thesis is to present a distributed source control infrastructure-based approach for mitigating the flood risk. The new flood mitigation approach is demonstrated through the model implementation of a series of distributed source control infrastructure systems in the city of Denham Springs at a neighborhood scale. The …

Water-Energy Nexus: Studies On Salinity Gradient Energy Harvest And Desalination, Guangcai Tan

LSU Doctoral Dissertations

Water and energy are fundamentally linked, and both are important for the development of human society. The demand for renewable energy and freshwater are two global challenges in the 21^st century. Herein, a novel chloride-ion (Cl⁻) concentration flow cell (CFC) based on two symmetrical electrodes (BiCl₃, CoCl₂, VCl₃, or BiOCl) separately by a cation-exchange membrane was used as an efficient method to recover salinity gradient (SG) energy. The CFC with metal chloride electrodes (BiCl₃, CoCl₂, and VCl₃) was based on Cl⁻ extraction/insertion, and that …

P-Cresol Biogenesis During Bioremediation Aimed At Stimulating Chlorinated Solvent Dehalogenation, Alexis Gathings

LSU Master's Theses

The broad goal of the research described in this thesis was to better understand the potential for biologically mediated production of p-cresol in groundwater at a Superfund site located in south Louisiana. Previous literature reports that microorganisms known to carry out the transformation from L-tyrosine to p-cresol occur in diverse environments.

In the research described in this thesis, studies were conducted utilizing groundwater from the Superfund site during the course of enhanced in situ bioremediation practices aimed at stimulating reductive dehalogenation of chlorinated solvent contamination. Microbial communities established with groundwater sampled from the Superfund site were observed to …

Understanding Air Pollutants And Meteorology Interactions Using Chemical Transport Models, Pengfei Wang

LSU Doctoral Dissertations

Air pollution is a worldwide threat to human health and ecosystems, especially in developing countries. After being emitted to the atmosphere, air pollutant concentrations are determined by chemical and physical processes including transport, transformation, and deposition, which are largely affected by meteorological variations. In turn, pollutants such as fine particulate matter (PM_2.5) affect meteorology by impacting solar radiation and cloud condensation processes. Thus, it is important and necessary to understand the interactions between air pollutants and meteorology for better designing effective air pollution control strategies and forecasting weather. In this study, two chemical transport models (CTMs) are applied …

Source Apportionment Of Ozone And Its Health Effects In North China Plain And Southeast U.S., Kaiyu Chen

LSU Doctoral Dissertations

Ground-level ozone (O₃), as one of six common air pollutants set by National Ambient Air Quality Standards from the U.S. Environmental Protection Agency (EPA), is of great interest due to its health and economical effects. However, O₃ contributions from different emission sources are not well understood due to its complicated nonlinear reactions. In this study, O₃ source apportionment methods and the applications are firstly reviewed to provide a comprehensive understanding for O₃ formations. Application of High-order Decoupled Direct Method (HDDM), brute force method (BFM), O₃ source apportionment technology (OSAT) and source-oriented method in O …

The Siltcatcher: A Sediment-Capture System For Wetland Creation And Coastal Protection In Western Lake Pontchartrain, Andrew M. Wright

LSU Master's Theses

The West Lake Pontchartrain region faces a number of long-term environmental challenges due to anthropogenic climate disturbance and landscape modification, including sea level rise, increased storm surge risk, shoreline erosion, and wetland degradation. In response, this thesis applies recent research in the fields of landscape architecture and civil engineering to propose a dynamic, natural-systems solution for wetland creation and shoreline protection. The project envisions a series of breakwater-like structures in western Lake Pontchartrain positioned to slow water released from the nearby Bonnet Carré Spillway, causing suspended sediment to settle and create self-building and self-sustaining wetlands capable of keeping pace with …

Investigation Of Tracer-Surfactant-Foam Processes In Shallow Subsurface Environmental Remediation: History-Matching And Performance Prediction, Hazem Fleifel

LSU Master's Theses

In-situ subsurface remediation has been widely used as an efficient means of cleaning up non-aqueous phase liquid (NAPL) from contaminated soils and aquifer. The use of tracer, surfactant, and foam are often considered to keep track of the propagation of injected fluids in the medium, dissolve and mobilize contaminants trapped by capillary forces, and overcome the level of heterogeneity and improve displacement and sweep efficiencies.

This study shows an actual remediation process to reduce NAPL within a military base in South Korea, by injecting tracer and surfactant solutions together for a duration of 10 days. The site consists of 5 …

Fate Of Eroding Crude Asphalt And Emulsion In Shallow Marsh Embayments, William Coronel

LSU Master's Theses

Marshes impacted by the Macondo spill continue to erode, releasing crude oil in the form of a soft asphalt or emulsion to adjacent shallow embayments. This process moves highly weathered crude oil from the marsh profile to comparatively high-energy, shallow, open-water systems where geochemical and microbiological conditions may influence additional weathering. Specifically, we hypothesize that the erosion process can accelerate biodegradation by moving crude oil asphalts and emulsions from a low-energy, anoxic environment in the marsh to a higher-energy, oxic environment in these shallow embayments. Sediment samples were taken in summer 2017 and 2018 across transects which bisect the boundary …

Automatic Shoreline Digitization And Mesh Element Sizing For Hydrodynamic Modeling, Henok Kefelegn

LSU Doctoral Dissertations

The first and most critical step in any coastal hydrodynamics and transport process modeling is identifying land-water boundaries. In a coastal wetland, this has always been a challenge due to the complexity of the wetland and lack of efficient methods, calling for efficient and effective methods to extract and digitize the shorelines. While coastline feature extraction has been increasingly researched, its application in hydrodynamic and environmental modeling, without morphological adjustment, remains limited and suboptimal. Further, there has been a paucity of cost-effective, contextually adaptive and high-quality methods to generate meshes, especially for coastal hydrodynamic modeling. This study has developed and …

Concentrations, Sources And Health Risks Of Particulate Matter In Southeast Us: Current Status And Future Changes, Fenglin Han

LSU Doctoral Dissertations

Evaluation of long-term air quality trends and prediction of future air quality may help to design and demonstrate effectiveness of control strategies and guide future air quality management. As one of the six criteria air pollutants (CAPs) regulated by the US Environmental Protection Agency (EPA), particulate matter with aerodynamic diameter of 2.5 µm or less (PM_2.5) is of great interests since it has adverse effects on human health, visibility and climate. This study aims to understand the current status and future changes in concentrations, sources, and health risks of PM_2.5 in Southeast US. Firstly, observations were analyzed …