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Full-Text Articles in Environmental Engineering

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot Jul 2022

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot

LSU Master's Theses

Coastal wetlands provide an abundance of ecosystem services that benefit society, such as essential habitat for commercial species, storm protection, nutrient cycling, and carbon storage. Louisiana faces rapid rates of relative sea level rise (natural subsidence and eustatic sea levels) that threaten wetland survival, which are amplified by a reduction of riverine sediment input. An important determining factor of marsh survival is the formation of wetland platform elevation, known as vertical accretion, which is determined by several processes including sediment deposition & erosion, below ground biomass (BGB) productivity, decomposition of organic matter, shallow & deep subsidence, and soil compaction. Feldspar …


Investigating The Proper Use Of Litani River Basin Based On Water Quality, Mohamad Diab, Mohamad Soliman Jun 2022

Investigating The Proper Use Of Litani River Basin Based On Water Quality, Mohamad Diab, Mohamad Soliman

BAU Journal - Science and Technology

Litani River Basin (LRB) with a 170km length and annual river flow of 750 MCM is considered the most important water resource in Lebanon. Unfortunately, the river is facing water contamination as a result of human practices. Water Quality assessments was performed in the Litani River Basin using a combination of Principal Component Analysis method (PCA) and Water Quality Index method (WQI). Results revealed the improvement of the water quality significantly after passing lake Qaraoun. Moreover, according to WQI, Lower LRB water is ranked ‘’Good’’ for irrigation and ‘’BAD’ for drinking purposes. Microbial contamination is found to be the key …


Mechanical And Durability Properties Of Geopolymer Concrete – A Review, Lelian Elkhatib, Fadi Al Aridi, Adel Elkordi, Jamal Khatib Jun 2022

Mechanical And Durability Properties Of Geopolymer Concrete – A Review, Lelian Elkhatib, Fadi Al Aridi, Adel Elkordi, Jamal Khatib

BAU Journal - Science and Technology

Owing to the ongoing increase in human population, there is a need for more construction projects including residential buildings and other amenities. Concrete is by far the dominant material used in construction and cement is a main ingredient. Cement manufacture is an energy intensive process and emit large amounts of carbon dioxide into the atmosphere. A reduction in the amount of cement used in construction is greatly beneficial. The use of geopolymer or alkali activated materials can serve this purpose as it attempts to totally replace cement in concrete. Geopolymers are materials that consist mainly of silica and alumina materials …


Evaluation Of Aluminum Dissolution, Current Density, And Pitting Patterns During Electrocoagulation, Monica Castro Carias Jun 2022

Evaluation Of Aluminum Dissolution, Current Density, And Pitting Patterns During Electrocoagulation, Monica Castro Carias

USF Tampa Graduate Theses and Dissertations

Electrocoagulation (EC) is a sustainable water treatment process involving the generation of coagulants on-site through the application of a voltage on metal (usually aluminum or iron alloys). The factors that impact EC system performance have been well researched, however further research is needed on the factors that impact anodic dissolution of aluminum electrodes, especially when the technology is transferred to full-scale applications. Electrode fouling is one of the factors that can impact dissolution of the anode during EC due to the formation of a protective oxide/hydroxide layer on the electrode surface. Previous studies have addressed electrode fouling by reversing polarity, …


Enhancing Management Of Built And Natural Water And Sanitation Systems With Data Science, Nelson Da Luz Jun 2022

Enhancing Management Of Built And Natural Water And Sanitation Systems With Data Science, Nelson Da Luz

Doctoral Dissertations

In the age of the data revolution, the civil engineer can enhance the management of infrastructure systems using new techniques focused on data. This dissertation present three studies in which data science approaches are used to enhance management of water and sanitation systems in both the built and natural environments. Chapters 1 and 2 focus on improving methods for data collection relating to water quality monitoring. In Chapter 1, the efficacy of different water quality sampling program designs is evaluated as the programs relate to meeting monitoring goals. Considerations include how timing, location, and distribution system operations can affect monitoring …


Effects Of Experimental Scale On The Adsorption Of Two Pharmaceutical Drugs Detected In Municipal Wastewater Effluent, Michael Moore Jun 2022

Effects Of Experimental Scale On The Adsorption Of Two Pharmaceutical Drugs Detected In Municipal Wastewater Effluent, Michael Moore

Master's Theses

Pharmaceutical drugs are being produced and consumed in increasing quantities every year and are poorly treated by conventional wastewater treatment processes, leading to increasing detection of such compounds in surface water, groundwater, and municipal drinking water. Soil aquifer treatment (SAT) is a promising method for treating these emerging compounds through combined adsorption and degradation of target compounds in soil. This thesis examines the consistency of results from typical studies like adsorption isotherms and soil columns utilized in analysis of SAT performance, across varying experimental scales. The adsorption behavior of two pharmaceuticals was investigated as a function of experimental scale and …


Environmental Design And Optimization Of Modular Hydropower Plants, Colin Sasthav May 2022

Environmental Design And Optimization Of Modular Hydropower Plants, Colin Sasthav

Doctoral Dissertations

This research aimed to understand the pathways to cost-effective and sustainable low-head hydropower. Designing viable hydropower projects requires optimization across many economic, environmental, and social outcomes. However, existing run-of-river hydropower design models often focus on economic performance and customizing technologies for high-head diversion schemes. Standard modular hydropower is a new design approach that uses standardized rather than custom-designed technologies to achieve economies of scale. Oak Ridge National Laboratory established a conceptual outline for module classes based on functions, such as generation modules and fish passage modules, but further research was needed to identify how modules should be selected and operated …


Port Infrastructure Resilience Through Combined Wind-Surge Demand Characterization, Kaley Callaway May 2022

Port Infrastructure Resilience Through Combined Wind-Surge Demand Characterization, Kaley Callaway

Graduate Theses and Dissertations

The United States economy is reliant on maritime transportation for 70% of imports and exports. Structures that are integral to the operation of ports, such as cranes, are jeopardized when tropical storms approach land. While wind is the only environmental load used to design dockside container cranes, storm surge often accompanies severe wind events and can create large structural loads. This study focuses on determining coupled storm-surge demands and the effect of waves on dockside container cranes. A damage index prediction tool that considers both maximum wind speed and storm surge height is developed and applied to historical hurricane data …


Sustainability In Construction Practices As Emphasis On Environmental Investing In Esg Model Grows, Maddie Heal May 2022

Sustainability In Construction Practices As Emphasis On Environmental Investing In Esg Model Grows, Maddie Heal

Management Undergraduate Honors Theses

The purpose of this research is to emphasize the importance of growing investment on environmental initiatives in business ESG models in regard to sustainable practices in construction. The ESG acronym is known as the environmental, social, and governance efforts that businesses strive to incorporate in their models to increase the responsibility of operations.

Investors continue to seek out responsible businesses when choosing which ventures to pursue. The analysis of the current construction crisis, current investments in the right direction of Eco-friendly design regarding construction, and the threats and benefits incentivizing those investments elucidates the need to emphasize socially responsible investment …


Community Transportation Needs And Willingness To Use Shared Micromobility: A Case Study Of Fort Smith, Arkansas, Anthony Michael Kammerer May 2022

Community Transportation Needs And Willingness To Use Shared Micromobility: A Case Study Of Fort Smith, Arkansas, Anthony Michael Kammerer

Civil Engineering Undergraduate Honors Theses

Shared micromobility is utilized in “targeted service areas with the usage generally intended for short trips such as "first- and last-mile" connections to complete trips made via other modes, including transit” (Price et al., 2021). In the United States, this practice has especially taken off with the implementation of sharing-based systems. This is evidenced by ridership numbers in the United States growing from 84 million riders nationwide in 2018 to 136 million riders in 2019 (NACTO, 2020). Users often use their smart phone or another similar device to unlock the vehicle after paying a fee on the device through their …


Urban Water Quality Monitoring And Analysis Using Event Detection System And Machine Learning Methods, Nabila Nafsin May 2022

Urban Water Quality Monitoring And Analysis Using Event Detection System And Machine Learning Methods, Nabila Nafsin

Theses and Dissertations

Water quality is defined as the measure of physical, chemical, and biological characteristics of water. Monitoring water quality is a growing challenge because of accidental or intentional spills of industrial, domestic, and agricultural wastes into surface water. Conventional methods used for measuring water quality parameters are time-consuming and expensive, making real-time contamination detection difficult. Advanced monitoring technology can be employed for real-time monitoring, providing a reliable and cost-effective solution to water management. CANARY event detection system (EDS) has been used in water distribution networks and wastewater treatment plants for detecting anomalous water quality events and proved to be an effective …


Hydropower System Design In Nazarét, Panama, Claudia M. Bible, Matthew J. Tolson, Andrew Houser, Aj Condra, Nathan Smith May 2022

Hydropower System Design In Nazarét, Panama, Claudia M. Bible, Matthew J. Tolson, Andrew Houser, Aj Condra, Nathan Smith

Chancellor’s Honors Program Projects

No abstract provided.


A Smart Illicit Discharge Monitoring System, Alexander Campbell, Henry S. Armstrong, Tien Yee Apr 2022

A Smart Illicit Discharge Monitoring System, Alexander Campbell, Henry S. Armstrong, Tien Yee

Symposium of Student Scholars

In the present study, we attempt to use a variety of sensors to monitor illicit discharges that are present near the Kennesaw State University Marietta Campus. The US Environmental Protection Agency defines an illicit discharge as “any discharge into a storm drain system that is not composed entirely of stormwater”. Each year, approximately 860 billion gallons of sewage spills are reported throughout the country. In Georgia, sewer spills data shows that spills may range from hundreds of gallons to millions of gallons depending on the severity of the leak. The undetected sewer leaks may degrade the water quality in nearby …


Analysis And Fate Of 2,6-Dichloro-1,4-Benzoquinone In Real And Model Drinking Waters, Aarthi Mohan Mar 2022

Analysis And Fate Of 2,6-Dichloro-1,4-Benzoquinone In Real And Model Drinking Waters, Aarthi Mohan

Doctoral Dissertations

For many years chlorination has served as a barrier to protect human health from waterborne disease outbreaks. Chlorine is viewed as a near-universal oxidant and disinfectant, that provides a stable residual preventing microbial re-growth all the way through the consumer’s tap. Upon reaction with natural organic matter (NOM) however, it forms disinfection by-products (DBPs) many of which are potent human carcinogens and therefore have been of research interest since the 1970’s (Froese et al., 1999; Krasner et al., 2006, 1989; Richardson, 2003; Rook, 1976, 1974; Singer, 1994). The trihalomethanes (THMs) and haloacetic acids (HAAs) are the most prevalent (Krasner et …


Implementation Of Secondary And Tertiary Treated Wastewater In Concrete Manufacturing, Amany G. Micheal Prof., Haidy Abd El Salm, Gouda Ghanem Prof. Mar 2022

Implementation Of Secondary And Tertiary Treated Wastewater In Concrete Manufacturing, Amany G. Micheal Prof., Haidy Abd El Salm, Gouda Ghanem Prof.

Centre for Advanced Materials

Water scarcity is a problem that faces many regions. In a developing and arid country like Egypt, the need for freshwater is exponentially increasing. This research is an evaluation of the recycled wastewater to be used in concrete manufacturing. The treated wastewater is blended with potable water with percentages of 25%, 50%, and 100%. The mixture of the two types of water is used in concrete mixing and curing. Control specimens with pure potable water are cast for comparison. The setting time for Ordinary Portland Cement is tested using the different water mixes. The hardened concrete is tested in compression …


Physical Investigation Of Downburst Winds And Applicability To Full Scale Events, Federico Canepa Feb 2022

Physical Investigation Of Downburst Winds And Applicability To Full Scale Events, Federico Canepa

Electronic Thesis and Dissertation Repository

Thunderstorm winds, i.e. downbursts, are cold descending currents originating from cumulonimbus clouds which, upon the impingement on the ground, spread radially with high intensities. The downdraft phase of the storm and the subsequent radial outflow that is formed can cause major issues for aviation and immense damages to ground-mounted structures. Thunderstorm winds present characteristics completely different from the stationary Gaussian synoptic winds, which largely affect the mid-latitude areas of the globe in the form of extra-tropical cyclones. Downbursts are very localized winds in both space and time. It follows that their statistical investigation, by means of classical full scale anemometric …


Erosion Control Of Steep Open Channels Using Articulated Concrete Blocks, Mohammadomid Marandi Feb 2022

Erosion Control Of Steep Open Channels Using Articulated Concrete Blocks, Mohammadomid Marandi

Electronic Thesis and Dissertation Repository

Overtopping flow can undermine the stability of hydraulic structures including embankments and spillways through the shear stress and the subsequent soil erosion. Increased flow velocity can cause scour, which can result in the failure of dams, bridges, and overall open channel hydraulic structures. Sediment transport is another crucial issue in open channels that can cause severe socioeconomic and environmental consequences. Two general approaches are commonly considered for scour prevention. The first approach involves flow modifications to minimize the corresponding effects on the structures. The second approach is associated with bed armoring and placing physical barriers on the natural bedding such …


Influence Of Foundation Damping On Offshore Wind Turbine Monopile Design Loads, Wystan Carswell, Sanjay R. Arwade, Jörgen Johansson, Don J. Degroot Jan 2022

Influence Of Foundation Damping On Offshore Wind Turbine Monopile Design Loads, Wystan Carswell, Sanjay R. Arwade, Jörgen Johansson, Don J. Degroot

Publications

The dynamic behavior of offshore wind turbines (OWTs) must be designed considering stochastic load amplitudes and frequencies from waves and mechanical loads associated with the spinning rotor during power production. The proximity of the OWT natural frequency to excitation frequencies combined with low damping necessitates a thorough analysis of sources of damping; of these sources of damping, least is known about the contributions of damping from soil-structure interaction (foundation damping). This paper studies the influence of foundation damping on cyclic load demand for monopile-supported OWTs considering the design situations of power production, emergency shutdown, and parked conditions. The NREL 5 …


North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev Jan 2022

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Theses

The following project report was a study of the North 14th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14th Street and the 14th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …


Comparison Of Phosphorus Removal And Recovery Methods And Proposed Design Of High Rate Algal Pond For Swine Wastewater, Taylor Fauth Jan 2022

Comparison Of Phosphorus Removal And Recovery Methods And Proposed Design Of High Rate Algal Pond For Swine Wastewater, Taylor Fauth

Civil and Environmental Engineering Graduate Students Plan B Capstone Projects

High phosphorus concentrations in wastewater effluent can have harmful effects to aquatic environments and water quality. An excess of nutrients such as phosphorus in water bodies will cause eutrophication, which depletes the available oxygen within the water and is detrimental to aquatic life. Additionally, phosphorus leaching from wastewater discharge has negative impacts to groundwater quality. The depletion of phosphorus as a natural resource is also of concern as phosphorus is an essential product for agricultural and industrial production. Phosphorus is a non-renewable resource, and natural sources are becoming more difficult and expensive to access. Therefore, the removal and recycle of …


Development Of Protocols For Determining Deleterious Material Content In Crushed Recycled Glass, Fiona Nutbeam Jan 2022

Development Of Protocols For Determining Deleterious Material Content In Crushed Recycled Glass, Fiona Nutbeam

Graduate College Dissertations and Theses

Glass recycling appears to be a viable way to reduce waste; however, there are many challenges to ensuring the recycled product has an economically and environmentally sustainable end use. Cleaning recycled glass to a standard that allows it to be melted down into new glass is extremely difficult when single-stream recycling is in practice. The recycled glass that is not melted down is processed into different materials, such as processed glass aggregate (PGA). As states implement bans on landfilling recyclable materials (e.g., Act 148 in Vermont), additional uses for PGA are needed. In New England, there are diminishing sources of …


Biodegradation Of Rubber Particles In Soil: Using Acclimated Bacteria Isolated From Kansas Soil To Degrade Cryogrinds In Slurry, Shane Graham Jan 2022

Biodegradation Of Rubber Particles In Soil: Using Acclimated Bacteria Isolated From Kansas Soil To Degrade Cryogrinds In Slurry, Shane Graham

Williams Honors College, Honors Research Projects

This study investigated the viability of bioremediating rubber cryogrind using enriched indigenous bacteria. To begin the experiment, soils from three highway roadside locations in Kansas, KS 96 and West, KS 400 and 143rd, and 199th, were collected and transported to the lab to be studied. An initial soil characterization was run on the soil samples using distilled (DI) water mixture and 0.01 M CaCl2 to assess conductivity. The soils were tested to gather a baseline of the relationship between pH and conductivity and the impact of its distance from the roadside. Bacteria were isolated from …


Sewer Vapor Intrusion Pathway: Simulation Of Indoor Piping Systems And Operation Of Aroma-Voc Gas Analyzer, Hong Cheng Tay Jan 2022

Sewer Vapor Intrusion Pathway: Simulation Of Indoor Piping Systems And Operation Of Aroma-Voc Gas Analyzer, Hong Cheng Tay

Theses and Dissertations--Civil Engineering

Vapor Intrusion (VI) is a transport phenomenon that occurs when contaminants migrate from sub-surface sources into indoor spaces. Sewer tunnels, plumbing connections, and piping infrastructures can be important contributors to an increased potential of VI in a site, which results in indoor concentrations of volatile organic compounds (VOC). In the present work, the topic of sewer VI pathways were investigated through a prototype made from various types of indoor plumbing pipe fittings. This prototype simulates indoor piping systems and determine whether air and VOC were escaping through the pipe fittings. Moreover, this study is the first effort to use a …


Investigation Of Pfas Exposure Risks In Kentucky Using Mapping Tools, Sweta Ojha Jan 2022

Investigation Of Pfas Exposure Risks In Kentucky Using Mapping Tools, Sweta Ojha

Theses and Dissertations--Civil Engineering

Per- and polyfluoroalkyl substances (PFAS), a group of environmentally-persistent compounds, are environmentally ubiquitous and challenging to remediate. Several studies show that PFAS are detected in drinking water systems when sampling is conducted, making human exposure via drinking water an important health consideration. This research: 1) develops a mapping tool for prioritizing sampling locations; 2) establishes a method for making GIS data and meta(data) in the mapping tool accessible; 3) fosters decision making by integrating knowledge brokering and the alignment interest and influence matrix (AIIM). The tool developed is this research is a geospatial and statistical PFAS hot-spot screening model that …


Climatic And Land Cover Sensitivities Of Stormwater Runoff In A Coastal Natural-Urban Basin Of Texas, Usa., Nusrat Nasrin Khan Jan 2022

Climatic And Land Cover Sensitivities Of Stormwater Runoff In A Coastal Natural-Urban Basin Of Texas, Usa., Nusrat Nasrin Khan

Graduate Theses, Dissertations, and Problem Reports

Changes in climatic and land use drivers typically drive stormwater runoff quantity and quality. This study focuses on determining the stormwater runoff sensitivities to variation in climatic and land cover changes in a coastal natural-urban basin. A mechanistic hydrologic model was developed for the Spring San Jacinto Basin (SSJB) of Texas, USA considering the basin as a pilot study area by using the U.S. Environmental Protection Agency (EPA)’s Storm Water Management Model 5.2. The SSJB drains an area of 1949 km2 ultimately into the northern Gulf of Mexico, USA through peripheral neighborhoods of the Greater Houston area. The model …


On A New Framework For Detecting, Classifying, And Forecasting Floods For Large-Scale Flood Risk Analysis, Equisha Glenn Jan 2022

On A New Framework For Detecting, Classifying, And Forecasting Floods For Large-Scale Flood Risk Analysis, Equisha Glenn

Dissertations and Theses

Increasing trends in flooding events are projected to continue as climate changes have increased the chance of extreme weather events. Given the significant, damaging impacts of extreme floods, the ability to effectively model floods is crucial for risk management and mitigation of the impacts of these extreme flooding events. This dissertation presents a new framework for detecting and predicting large-scale flood risk in the United States using climate information. This methodology categorizes regional, simultaneous floods into an index that is used to forecast the risk of extreme flooding a season ahead. The index proposed herein, named the Spatial Flood Index …


Using Stream Restoration To Mitigate Stormwater Runoff In An Urban Watershed: A Case Study, Jonathan M. Brantley Jan 2022

Using Stream Restoration To Mitigate Stormwater Runoff In An Urban Watershed: A Case Study, Jonathan M. Brantley

Theses and Dissertations--Biosystems and Agricultural Engineering

The goal of this case study was to evaluate the effectiveness a 275 m regenerative stream restoration design to mitigate stormwater runoff in a highly urbanized watershed. The restoration resulted in a wide, wetland-like floodplain, comprised of a rock base that was overtopped with a filtration media (approximately 30% woodchips and 70% topsoil). The creation of the floodplain-wetland complex in tandem with filtration media lead to increased storage capacity and an increase in hyporheic exchange within the system. Significant reductions were found for the storm hydrograph parameters volume, peak discharge, and time to peak. Reductions in baseflows were also noted …


Stormwater Runoff Response Under Changing Climate And Land Uses Across Gradients Of Inland And Coastal Urban-Natural Basin, Mahmood Khan Jan 2022

Stormwater Runoff Response Under Changing Climate And Land Uses Across Gradients Of Inland And Coastal Urban-Natural Basin, Mahmood Khan

Graduate Theses, Dissertations, and Problem Reports

Climatic variability has caused significant shifts in the magnitude, frequency and spatiotemporal distribution of precipitation, generating excessive runoff that leads to frequent occurrences of extreme hydrologic events such as the pluvial (rainfall accumulation) and fluvial (riverine) floods. The conversion of natural areas into urban lands is further exacerbating the rainfall accumulation by increasing surface imperviousness that hinders infiltration of water into the soil. This dissertation predicts and characterizes potential shifts in the future annual stormwater runoff
volumes and runoff extremes under the standalone and coupled changes in climate and land use across inland and coastal urban-natural settings. The research was …


Stormwater Sensitivities To The Climatic And Land Cover Drivers In A Heavily Urbanized Coastal Basin Along The Northern Gulf Of Mexico, Usa., Md Faisal Razy Jan 2022

Stormwater Sensitivities To The Climatic And Land Cover Drivers In A Heavily Urbanized Coastal Basin Along The Northern Gulf Of Mexico, Usa., Md Faisal Razy

Graduate Theses, Dissertations, and Problem Reports

Stormwater runoff response in a complex coastal-urban basin varies with the changes in climatic and land cover drivers. This thesis aims to assess the runoff responses to variation in climatic and land cover variables and perform a sensitivity analysis in complex coastal-urban basins. The Buffalo San Jacinto Basin (BUSJ) of southeast Texas, USA was considered a pilot study area for this research. BUSJ is a heavily urbanized coastal basin, draining an area of 3132 km2 through the City of Houston, Texas into the northern Gulf of Mexico, USA. A process-based hydrological model was developed with fine spatio-temporal resolutions for …


Maximum Profit Facility Location And Dynamic Resource Allocation For Instant Delivery Logistics, Darshan Chauhan, Avinash Unnikrishnan, Stephen D. Boyles Jan 2022

Maximum Profit Facility Location And Dynamic Resource Allocation For Instant Delivery Logistics, Darshan Chauhan, Avinash Unnikrishnan, Stephen D. Boyles

Civil and Environmental Engineering Faculty Publications and Presentations

Increasing e-commerce activity, competition for shorter delivery times, and innovations in transportation technologies have pushed the industry toward instant delivery logistics. This paper studies a facility location and online demand allocation problem applicable to a logistics company expanding to offer instant delivery service using unmanned aerial vehicles or drones. The problem is decomposed into two stages. During the planning stage, the facilities are located, and product and battery capacity are allocated. During the operational stage, customers place orders dynamically and real-time demand allocation decisions are made. The paper explores a multi-armed bandit framework for maximizing the cumulative reward realized by …