Environmental Engineering Commons^™

Impact Of Upstream Chlorination On Filter Performance And Microbial Community Structure Of Gac And Anthracite Biofilters, Glen Andrew De Vera, Daniel Gerrity, Mitchell Stoker, Wilbur Frehner, Eric C. Wert

Civil and Environmental Engineering and Construction Faculty Research

Drinking water filters may be operated to promote or deter biological activity through upstream oxidant addition. While there are several water quality benefits from biofiltration, microbial growth in biofilters warrants further investigation. In this study, routine monitoring detected target DNA sequences for Naegleria fowleri in source water and Acanthamoeba spp. in source water and biofilter effluent, triggering further microbial community characterization. Full-scale anthracite and granular activated carbon (GAC) filters receiving chlorinated waters were compared in terms of effluent water quality (i.e., turbidity and particle counts), biological activity (i.e., adenosine triphosphate (ATP)), and the composition of the microbial community (i.e., 16S/18S …

N-Nitrosodimethylamine Formation And Mitigation In Potable Reuse Treatment Trains Employing Ozone Nd Biofiltration, Fernanda Bacaro

UNLV Theses, Dissertations, Professional Papers, and Capstones

Potable reuse has been growing as a strategy to augment water supplies, especially in highly populated and water-scarce regions. Ozone and chloramines have emerged as important disinfectants and oxidants in potable reuse applications, but reactions with wastewater-derived constituents can lead to the formation of potentially carcinogenic disinfection byproducts (DBPs). One DBP that has received considerable attention is the nitrogenous DBP N-nitrosodimethylamine (NDMA). NDMA is a potential human carcinogen and mutagen at trace concentrations — even at the sub-ng/L level. Several studies have reported successful attenuation of NDMA in biofiltration systems at wastewater treatment plants, but the associated mechanisms and design …

Evaluating The Feasibility And Sustainability Of Direct Potable Reuse In Las Vegas, Nv, Cory Dow

UNLV Theses, Dissertations, Professional Papers, and Capstones

Community water sources are becoming more and more strained due to several factors including severe drought, population growth, urbanization, and climate change. This has spurred several water agencies to evaluate alternative water supply options to extend their resources. One potential alternative is potable reuse. Potable reuse comes in two forms: indirect potable reuse (IPR) and direct potable reuse (DPR). IPR is the advanced treatment of wastewater effluent before discharging into an environmental buffer that is a drinking water supply such as a lake, river, or groundwater aquifer before extraction and use. DPR is the advanced treatment of wastewater effluent that …

The Impact Of Waters Of Low Quality On Soiling Removal From Photovoltaic Panels, Alisson Luiz Boeing

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soiling, bird droppings, or the accumulation of dust on the surface of photovoltaic cells, can significantly reduce the solar energy absorption and produce power losses. In solar plants where soiling is a problem, solar facilities use demineralized or distilled water for washing the panels to avoid mineral scale deposits that might interfere with solar irradiance absorption. However, in arid and dusty environments, water is normally scarce. For cleaning solar panels, the use of low quality water in lieu of the industry-standard demineralized water could conserve fresh water. The objectives of this research were as follows: evaluate the impacts of low …

Static And Dynamic Quantitative Microbial Risk Assessment Of Potable Reuse Paradigms, Erfaneh Amoueyan

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, potable reuse applications have become more common due to population growth and increased water demand, especially in communities with limited or variable water resources. However, there are concerns about potential exposure to pathogens and chemical compounds in treated wastewater. Therefore, advanced wastewater treatment processes are of paramount importance in any potable reuse system. The overall aim of this study was to develop and implement static and dynamic QMRAs to compare public health risk in various potable reuse scenarios. Cryptosporidium, norovirus, adenovirus, and Salmonella were chosen as the target pathogens. The research evaluated the performance of full advanced …

The Future Of Construction As It Applies To The Colonization Of The Moon And Mars, Julian Prestia

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goals of this research are:

1. To compile a comprehensive list of all the viable known solutions (and early stage potential solutions) to the issues related to constructing permanent, sustainable, and safe structures for human colonies on our moon and Mars,

2. Determine the most effective potential solutions, and

3. Further develop these ideas as to assist in further space endeavors.

This proposed paper will assist space experts in determining the best next steps in the development of deep-space travel and colonization technologies. Preliminary research has identified several key problems associated with establishing space colonies. They are as follows: …

College Of Engineering Senior Design Competition Fall 2017, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Understanding The Long-Term Changes In Hydrologic Processes On A Watershed Scale Due To Climate Variability And Change, Chao Chen

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past century, the population explosion and economic development have resulted in global warming, which has raised a series of concerns, such as sea-level rise, food security, and water resources management. The water flow patterns and features experience both short-term and long-term changes in responses to the changes in the hydrologic processes and meteorologic conditions. On a watershed scale, it is crucial to understand, quantify, and attribute the influences of climate change on the local water resources system. Such understanding can be of great help to undertake local water management tasks, such as flood control, reservoir operation, ecosystem services, …

Evaluating The Chemical And Biological Stability Of Finished Waters Blended For Direct Potable Reuse In A Simulated Distribution System, Assumption Grimaldi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work evaluated the impacts of blending several different high grade recycled waters with conventional source waters for direct potable reuse (DPR) applications. Bench-scale laboratory tests were conducted for recycled water-source water blends from four participating facilities that have either considered adopting DPR or have already implemented DPR as a feasible approach to overcome water scarcity. The chemical and biological stability of the finished waters was investigated after pipe rig incubation to simulate the quality of blended waters that had aged in a potable water distribution system. The effects of blend ratio, reclaimed water treatment, and source water quality were …

College Of Engineering Senior Design Competition Spring 2017, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Impacts Of Ozone Dose And Empty Bed Contact Time On Bulk Organic Removal And Disinfection Byproduct Mitigation In Ozone-Biofiltration Systems, Mayara Aquino

UNLV Theses, Dissertations, Professional Papers, and Capstones

In areas where water shortages have compromised water supplies, potable reuse is a promising solution. However, additional research is needed to identify and/or optimize cost-effective treatment technologies to demonstrate compliance with potable reuse regulations. Treatment trains employing reverse osmosis (RO) and advanced oxidation, a combination known as ‘full advanced treatment’ (FAT), are required by the California Division of Drinking Water (CDDW) for surface water augmentation and direct injection of recycled water into local aquifers. A maximum concentration of 0.5 mg/L of wastewater-derived total organic carbon (TOC) is also required by CDDW in all groundwater recharge applications. This appears to be …

Effect Of Inlet Angle From Tributary Into Main Channel, Artuan Mcgee, Moses Karakouzian

AANAPISI Poster Presentations

Open channel flows play a significant role within major metropolitan areas in the removal of excess surface runoff. Main channels are responsible for the removal of all excess surface runoff which are fed by connecting tributaries. Both main channels and tributaries can occur naturally or be manmade but their orientation must be considered in the removal of excess surface run off. It is believed that the angle in which the tributaries connect to the main channel is an important factor in whether the run off is removed efficiently or a major contributor to flooding. Current practice requires tributaries in flood …

College Of Engineering Senior Design Competition Fall 2016, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Evaluation Of Electron Donors For Perchlorate And Nitrate Biodegradation In Contaminated Groundwater Applications, Mayra Alejandra Sarria Cortes

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the United States, perchlorate contamination has been widely reported, including in Las Vegas, Nevada, where perchlorate has been detected at concentrations of 34.7 mg/kg in vadose zone soil and 0.18-3.7 g/L in groundwater. Once this groundwater reaches the Las Vegas Wash, there is potential for widespread contamination of drinking water sources throughout the Southwest, including in Nevada, Arizona, and California. This issue is becoming increasingly important because even at low perchlorate concentrations, sensitive populations such as infants and pregnant women can be potentially impacted due to perchlorate’s ability to hinder iodine uptake into the thyroid glands, which leads to …

Occurrence And Proliferation Of Antibiotics And Antibiotic Resistance In Wastewater Treatment Plants, Majid Neyestani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solids retention time (SRT) is one of the most important factors in designing and operating activated sludge systems for biological wastewater treatment. Longer SRTs have been shown to alter the structure and function of microbial communities, thereby leading to improved treatment efficacy with respect to bulk and trace organics, nutrient removal, and membrane fouling. However, research has also shown that longer SRTs lead to increased prevalence of antibiotic resistant bacteria, perhaps due to increased exposure to antibiotics present in influent wastewater. The purpose of this study was to characterize changes in microbial community structure in a laboratory-scale activated sludge system …

College Of Engineering Senior Design Competition Spring 2016, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Ozonation In Water Reuse: Formation And Mitigation Of N-~Nitrosodimethylamine, Erica J. Marti

UNLV Theses, Dissertations, Professional Papers, and Capstones

Formation of N-nitrosodimethylamine (NDMA) is a substantial concern for drinking water and water reuse. NDMA, a probable human carcinogen, is formed when water is disinfected with chloramines and ozone. This research focused on three issues regarding NDMA formation and mitigation. The first issue involved understanding the compounds (i.e., precursors) present in water and wastewater that react with ozone to form NDMA. Model precursors were identified and molar yields for NDMA formation were determined. The model precursors form high amounts of NDMA with ozone, but form very little NDMA with chloramines, which means there are two distinct groups of NDMA precursors: …

Removal Of High And Low Levels Of Ammonium From Industrial Wastewaters, Gregory Bock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Over 2×10^11 kilograms of ammonia are produced globally per year by the Haber-Bosch process which combines molecular hydrogen and nitrogen to synthesize ammonia. Most is used for fertilizer and agriculture while the remaining is used for other purposes including industrial processes and explosives. Explosives used in the mining industry are commonly ammonium nitrate (����4����3)-based. Excess ammonia and nitrate which can be dissolve into mine runoff water during blasting. Ammonia in mine and mineral wastewater can range from 20-110 mg/L. Ammonia is also present in several types of industrial wastewater such as caustic soda solutions used in the oil re-refining industry …

Perchlorate Bioremediation: Controlling Media Loss In Ex-Situ Fluidized Bed Reactors And In-Situ Biological Reduction By Slow-Release Electron Donor, Sichu Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

The main concern of perchlorate exposure through drinking water is its effects on the production of thyroid hormone, which is important for human metabolism and child’s brain development. The US Environmental Protection Agency (EPA) has listed perchlorate in the contaminant list as well as in the Unregulated Contaminant Monitoring rule.

The extent of perchlorate contamination can be categorized by the level of contamination into parts per million (ppm) levels, typically in locations where perchlorate was manufactured, and parts per billion (ppb) levels where perchlorate was used for various purposes. Ion-exchange is generally adopted for treating ppb levels of perchlorate while …

College Of Engineering Senior Design Competition Fall 2015, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Fluoride And Phosphate Removal From Industrial And Domestic Wastewaters Using Cerium Chloride, John Michael Gonzales

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of cerium chloride (CeCl3) to remove fluoride and phosphate from waters is addressed in this study. High concentrations of fluoride exist in groundwater especially in developing countries. Consumption drinking water containing high levels of fluoride can lead to serious cases of dental and skeletal fluorosis. Current defluoridation technologies are limited, especially for high levels of fluoride, and are expensive. Industrial wastewaters contribute to the highest fluoride contamination in the world. With the increasing production of electronic materials, the global fluoride concentration and fluoride-contaminated waters have grown tremendously. Excessive discharge of phosphate into the environment promotes eutrophication of lakes …

College Of Engineering Senior Design Competition Spring 2015, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

The Use Of Cod, Toc, Fluorescence, And Absorbance Spectroscopy To Estimate Biochemical Oxygen Demand In Wastewater, Evelyn Aramaine Christian

UNLV Theses, Dissertations, Professional Papers, and Capstones

All wastewater treatment facilities must obtain a National Pollution Discharge Elimination System (NPDES) permit, which regulates the quality of water that is discharged. Common to all NPDES permits is a limit on organic matter, as determined by the five-day biochemical oxygen demand (BOD5) test. More rapid methods, such as chemical oxygen demand (COD), total organic carbon (TOC), fluorescence, and absorbance spectroscopy are also capable of quantifying organic matter. Previous studies indicate it is possible to develop correlations between these parameters. This study explored the correlations using influent, primary clarifier effluent, and finished effluent samples from an operational wastewater treatment plant …

Impacts Of Ozone Dose And Empty Bed Contact Time On Total Organic Carbon Removal Through Ozone-Biological Activated Carbon Treatment, Ashley Selvy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the face of climate change, pollution, and population growth, water scarcity has become a global threat. Many populations have witnessed their drinking water sources dwindle to an unsustainable level. These severe conditions have sparked interest in potable reuse as an increasingly viable alternative to typical ‘pristine’ drinking water sources. Currently, the California Division of Drinking Water (DDW) provides the most stringent requirements for reuse water quality. The best way to meet these standards is through the use of full advanced treatment (FAT), which consists of reverse osmosis (RO) and an advanced oxidation process (AOP). Alternative treatment trains composed of …

College Of Engineering Senior Design Competition Fall 2014, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

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 …

College Of Engineering Senior Design Competition Spring 2014, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Management Of Water Resources In Shanshan, China: A System Dynamic Approach, Chao Chen, Zhixia Xu, Ajay Kalra, Sajjad Ahmad

College of Engineering: Graduate Celebration Programs

Shanshan County, located in Xinjiang, China, has severe problems of water scarcity, overexploitation of groundwater. In need of efficient water resources management strategies, this study proposes a System Dynamics (SD) approach to simulate the water resource allocation, which can assist in providing a better understanding of the dynamic water supply and demand system and exploring different water resources management and allocation scenarios.

Incorporating The Oceanic-Atmospheric Climate Variables To Enhance Streamflow Reconstruction Skill, Saria Bukhary, Parker Hill, Ajay Kalra, Sajjad Ahmad

College of Engineering: Graduate Celebration Programs

Streamflow is a vital source of water supply. Information about the historic streamflow helps understand the range of climate variability and develop sustainable water management strategies for the future. The available instrumental data is usually limited and thus might be insufficient to describe the long-term hydrologic patterns of a region. Streamflow reconstruction, by increasing the length of the hydrologic data, is an important tool to understand past hydrology.