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Full-Text Articles in Civil and Environmental Engineering

Artificial Recharge Of Groundwater As A Management Tool For The Kabul Basin, Afghanistan, Mohammad Farid Masoom Mar 2018

Artificial Recharge Of Groundwater As A Management Tool For The Kabul Basin, Afghanistan, Mohammad Farid Masoom

LSU Master's Theses

Decades of war and political instability, consecutive droughts, population increase and displacement, caused serious infrastructural damages to water resources of Afghanistan. The main source of water supply for people in Afghanistan is groundwater. However, over-exploitation of groundwater has led to groundwater level declines in most parts of the country. Kabul, the largest city of Afghanistan, is the capital city with a population of 4.5 million and the fifth fastest-growing city in the world. The city has observed groundwater level declines of 5-10 meters (m) since 1980. Decline of about 30 m has also been observed in one of the monitoring …


Field Testing Of Affordable Well Head Protection For Locally Manufactured, Self-Supply Pitcher Pumps On Manually Driven Tubewells In Madagascar, Michal Usowicz Mar 2018

Field Testing Of Affordable Well Head Protection For Locally Manufactured, Self-Supply Pitcher Pumps On Manually Driven Tubewells In Madagascar, Michal Usowicz

USF Tampa Graduate Theses and Dissertations

Lack of water access is an issue of global importance. The WHO and UNICEF’s Joint Monitoring Program estimated that in 2015 71% of the world’s population used a safely managed drinking water source and 89% of the world’s population used an improved water source within a 30-minute round trip of home. Madagascar’s national statistics lags far behind these global statistics with 54% of the population using improved water sources, 31% using unimproved water sources, and 16% with no service at all.

This research studied water access in Madagascar with self-supply Pitcher Pumps attached on hand-driven tubewells. The term self-supply in …


An Evaluation Of The Groundwater Microbial Community's Toluene Biogenesis Potential At A Site In Southeast Louisiana, Michael A. Griffin Jr. Jan 2018

An Evaluation Of The Groundwater Microbial Community's Toluene Biogenesis Potential At A Site In Southeast Louisiana, Michael A. Griffin Jr.

LSU Master's Theses

The broad goal of the research described in this thesis was to better understand the potential for biological toluene production to occur in groundwater at a Superfund Site located in southeast Louisiana. Previous literature reported that bacterial isolates under laboratory test conditions and undefined microbial communities in anaerobic sludge digesters and seasonally stratified lakes can produce toluene biogenically. Most of the research reported on this subject previously, however, has been on systems in Europe and little research has been reported previously on such phenomena in North America.

In the research described here, studies were conducted utilizing groundwater from a Superfund …


Remotely Sensed Hydroclimatic Variability For Water Security In An Agricultural Basin, Ashish Kondal Jan 2018

Remotely Sensed Hydroclimatic Variability For Water Security In An Agricultural Basin, Ashish Kondal

Graduate Theses, Dissertations, and Problem Reports

The Indus Basin has supported agricultural practices since the Harappan civilization (3000-1500 BC). Abundance of water has always supported agriculture in the region and built the Indus Basin as one of the major agriculture based economies of the world. The obvious dependency of agriculture on weather and the vagaries of climate emphasizes the necessity of a comprehensive hydro-climate study of the region. The role of climate change in the Indus Basin has always been a contentious issue. Groundwater depletion is evident in the region, and its steady and alarmingly declining rate has brought concerns for the future of agriculture in …


Enumeration, Variability, And Transport Of Escherichia Coli In The Foreshore Reservoir And Surface Water At Freshwater Beaches, Laura J. Vogel Oct 2017

Enumeration, Variability, And Transport Of Escherichia Coli In The Foreshore Reservoir And Surface Water At Freshwater Beaches, Laura J. Vogel

Electronic Thesis and Dissertation Repository

Beaches are of immense recreational, societal and economic value. This value, however, is considerably diminished by poor water quality. Fecal indicator bacteria (FIB) are measured at recreational beaches worldwide to assess the water quality. A beach closure or advisory is issued if FIB concentrations in surface water exceed recreational water quality standards. Due to the lengthy time required to enumerate FIB (24 – 96 hours), statistical and mechanistic models have been developed to predict water quality exceedances a priori and to better understand why and under what conditions water quality exceedances occur. These models as well as beach water quality …


Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs Sep 2017

Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs

Theses and Dissertations

This work examined ultraviolet (UV) light emitting diodes (LED) and hydrogen peroxide in an advanced oxidation process in support of a USAF installation net zero water initiative. A UV LED reactor was used for degradation of soluble organic chemicals. There were linear relationships between input drive current, optical output power, and first order degradation rate constants. When drive current was varied, first order degradation rates depended on chemical identities and the drive current. When molar peroxide ratios were varied, kinetic profiles revealed peroxide-limited or radical-scavenged phenomena. Molar absorptivity helped explain the complexity of chemical removal profiles. Degradation kinetics were used …


Enhancing The Performance Of Anaerobic Bioreactors For The Biological Degradation Of Volatiles Organic Compounds In Groundwater Using Alternate Electron Acceptors, Leslie Michele Pipkin Aug 2017

Enhancing The Performance Of Anaerobic Bioreactors For The Biological Degradation Of Volatiles Organic Compounds In Groundwater Using Alternate Electron Acceptors, Leslie Michele Pipkin

LSU Doctoral Dissertations

Engineered anaerobic bioreactors (ABR) constructed from mixed media and sand can biodegrade high concentrations of volatile organic compounds (VOCs). Sustainable treatment of benzene, toluene, ethylbenzene, and xylenes (BTEX), chlorinated ethenes and ethanes were used to investigate the use of engineered ABRs, while also analyzing the system performance of a full-scale ABR system. Experimentations conducted on environmental and biological factors that affect ABR system performance was conducted through serum bottles, columns, and reactor studies.

Column and reactor ABR systems were designed to treat VOCs via biodegradation in groundwater with varying terminal electron acceptors (TEAs). Laboratory-scale column ABRs were constructed to treat …


Identifying Corrosion Zones In Coastal Regions For Metal Pipes -- A Gis Approach, Sanjay Tewari, Francis Manning Aug 2017

Identifying Corrosion Zones In Coastal Regions For Metal Pipes -- A Gis Approach, Sanjay Tewari, Francis Manning

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transportation agencies often allow metal pipes as an option for cross drains under/along roads and highways. Metal culverts can corrode over time at various rates based on their environmental conditions (e.g., corrosive nature of coastal soils, high water table and saltwater intrusion). This paper focuses on applying readily available soil data such as spatial distribution of soil types and soil characteristics (e.g., pH and conductivity) towards creating a geospatial information system (GIS) based approach to identifying corrosion zones in the coastal regions. A combination of data, obtained from field surveys provided by the Louisiana Transportation Research Center and Web Soil …


Evaluation Of Electron Donors For Perchlorate And Nitrate Biodegradation In Contaminated Groundwater Applications, Mayra Alejandra Sarria Cortes Dec 2016

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 …


The Role Of Organic Matter In The Fate And Transport Of Antibiotic Resistance, Metals, And Nutrients In The Karst Of Northwest Arkansas, Victor Lee Roland Ii Aug 2016

The Role Of Organic Matter In The Fate And Transport Of Antibiotic Resistance, Metals, And Nutrients In The Karst Of Northwest Arkansas, Victor Lee Roland Ii

Graduate Theses and Dissertations

Organic matter (OM) in the environment acts as a nutrient, but may also act as a transport vector for harmful chemical compounds and bacteria. Acetate is a labile form of OM produced during fermentation in anaerobic lagoons used to store animal fecal-waste from concentrated animal feeding operations (CAFOs). Dry and liquid fertilizers from CAFOs pose a threat to groundwater by introducing excessive amounts of nutrients (e.g. OM, nitrate and ammonia), metals, and antibiotic compounds. In the epikarst of Northern Arkansas in the Buffalo River watershed additional input of labile dissolved organic carbon (DOC) from liquid CAFO waste-fertilizers was hypothesized to …


Development And Assessment Of A Groundwater Sustainability Index In Climatically Diverse Groundwater Irrigated Regions In Nebraska, Maria A. Mulet Jalil Jul 2016

Development And Assessment Of A Groundwater Sustainability Index In Climatically Diverse Groundwater Irrigated Regions In Nebraska, Maria A. Mulet Jalil

Department of Biological Systems Engineering: Dissertations and Theses

The aim of this research was to evaluate the impact of regional change in ET on groundwater level changes and the assessment and development of a groundwater sustainability index for climatically diverse regions across Nebraska during 2000-2014. Irrigation in the selected regions is predominantly supplied by groundwater. The hypothesis is that groundwater use can become sustainable if the regional evapotranspiration (ET) is managed so that it equals the ET of vegetation that is native to the region. Site locations were Box Butte, Chase, Dundy, Holt LNNRD and York Counties and 3 ecosystems were evaluated: native vegetation, dryland and irrigated cropping …


Ncma Groundwater Model Using Usgs Modflow-2005/Pest, Brian Matthew Wallace Jun 2016

Ncma Groundwater Model Using Usgs Modflow-2005/Pest, Brian Matthew Wallace

Master's Theses

A numerical model for the NCMA aquifer complex is presented. The objective of the study is to develop a numerical groundwater model for the NCMA aquifer system to enhance the understanding of subsurface groundwater flow. Infiltration, streamflow, pumping, and return flows are implemented to characterize the aquifer complex over time. The numerical model is calibrated to municipal and monitoring well data, average monthly water balances, and hydraulic contours. Transient aquifer inflows and outflows are assessed in the results of the study and are compared to balance terms from previous studies. The 2007 Todd Engineers Study subsurface inflows and outflows generate …


Hydrogeological Conceptual Model Of La Villa River Watershed, Republic Of Panama, Maria G. Castrellon Romero Apr 2016

Hydrogeological Conceptual Model Of La Villa River Watershed, Republic Of Panama, Maria G. Castrellon Romero

Honors Scholar Theses

Groundwater in Panama is a valuable and poorly understood resource. Its exploitation has increased 75% in the past decade, reaching a total value of 700,000 m3/day or 185 million gallons per day (MGD). Climate change has caused a lengthening of the dry season, which has reduced precipitation and streamflow, resulting in surface water scarcity during this period. Nevertheless, it has not been possible to determine the extent to which groundwater sources have been affected by these factors since systematic monitoring of groundwater levels has not been implemented in Panama. With support from National Institution of Drinking Water Supply …


Evaluating Groundwater Recharge In The Saloum Region Of Senegal, Alexander Wohlgemuth Jan 2016

Evaluating Groundwater Recharge In The Saloum Region Of Senegal, Alexander Wohlgemuth

Dissertations, Master's Theses and Master's Reports

Approximately 1.2 billion people in the world live in an area facing physical, or absolute, water scarcity (defined as access to less than 1,000 cubic meters of water). This number is projected to increase to 1.8 billion by the year 2025. Thirty-eight percent of the world’s population lives in arid, semi-arid or dry subhumid regions, which translates to a high dependence on the 30% of the world’s freshwater present in the ground. Further, the rate of water use is increasing rapidly – between two and two and a half times that of population growth, over the last century.

In regions …


Silver Nanoparticle Transport Through Soil: Illuminating The Governing Pore-Scale Processes, Ian L. Molnar Dec 2015

Silver Nanoparticle Transport Through Soil: Illuminating The Governing Pore-Scale Processes, Ian L. Molnar

Electronic Thesis and Dissertation Repository

Engineered nanoparticles are widely used and will eventually be released to the subsurface environment and contaminate groundwater resources. However, the transport of engineered nanoparticles through soil is currently not well understood and cannot be modelled in any fundamental manner, placing groundwater resources at risk from nanoparticle contamination. This inability to accurately simulate transport is due to a lack of experimental information on nanoparticle interactions in the pore spaces of real soils.

This thesis illuminates the pore-scale processes governing silver nanoparticle transport through soil. In addition, it examines the influence of surface chemistry and grain/pore distributions on those processes. For the …


Enhancing The Link Between Surface And Groundwater Models For Climate Change Assessment Of Water Supply And Demand In Northwest Mexico, George Whitten, Matthew Hann, Agustin Robles-Morua, Alex S. Mayer, Enrique R. Vivoni Jun 2014

Enhancing The Link Between Surface And Groundwater Models For Climate Change Assessment Of Water Supply And Demand In Northwest Mexico, George Whitten, Matthew Hann, Agustin Robles-Morua, Alex S. Mayer, Enrique R. Vivoni

International Congress on Environmental Modelling and Software

The integrated use of surface and groundwater models is critical for analyzing water resources sustainability. We have applied surface and groundwater models to the Sonora River basin (SRB) in Northwest Mexico within the context of participatory modeling with stakeholders to explore alternative futures under climate change impacts. The models are used to assess the hydrologic consequences of temperature and precipitation scenarios generated through the dynamical downscaling using the Weather Research and Forecast (WRF) model for historical, near-future and far- future study periods. WRF is used to downscale two global circulation models (GCMs), HadCM3 and MPI-ECHAM5. Improved representation of surface-groundwater interactions …


Management Of Water Resources In Shanshan, China: A System Dynamic Approach, Chao Chen, Zhixia Xu, Ajay Kalra, Sajjad Ahmad May 2014

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.


An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter May 2014

An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter

USF Tampa Graduate Theses and Dissertations

Rural improved water supply coverage in Uganda has stagnated around 64% for a number of years and at this point more than 10 million rural people do not have access to an improved drinking water source. It has been recognized that progress toward improved water supply coverage and increased service levels may be gained through Government and nongovernmental organization (NGO) support of private investment in household and shared water supplies, commonly known as Self-supply. Self-supply can be promoted by introducing and building local capacity in appropriate and affordable water supply technologies such as hand-dug wells, manually drilled boreholes, low-cost pumps, …


Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom May 2014

Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom

USF Tampa Graduate Theses and Dissertations

It has been reported that globally we have achieved Millennium Development Goal (MDG) Target 7C, to halve the proportion of the population without access to safe drinking water; however, there is a major flaw with this statement. While Target 7C calls for access to `safe' drinking water, what is actually being measured and reported is access to an `improved' water source. The World Health Organization (WHO) maintains that they must use this proxy measure because the methods for water quality testing are too expensive and logistically complicated, but by doing so, they may be over reporting safe water coverage.

This …


Evaluation Of Hand Augered Well Technologies' Capacity To Improve Access To Water In Coastal Ng[Oumlaut]Be Communities In Panama, Sarah Hayman Mar 2014

Evaluation Of Hand Augered Well Technologies' Capacity To Improve Access To Water In Coastal Ng[Oumlaut]Be Communities In Panama, Sarah Hayman

USF Tampa Graduate Theses and Dissertations

Amid the global efforts surrounding United Nations' Millennium Development Goal Target 7c to improve access to safe and sustainable drinking water among populations who lack this resource, it has become essential to monitor and evaluate progress. Development initiatives working to achieve improved drinking water access often introduce appropriate technologies designed to be sustainably owned and operated by populations in rural areas suffering from water related hardships. It is valuable to thoroughly examine the degree to which these technologies satisfy intended objectives and affect user experienced water access. The accurate reflection of impact and progress can be complex, as the evaluation …


Analyses Of Groundwater Contribution To A Riverine Wetland, Farzad Mahmoodinobar Jan 2014

Analyses Of Groundwater Contribution To A Riverine Wetland, Farzad Mahmoodinobar

Dissertations

Rainfall, runoff, overbank flow and groundwater, all contribute water to wetlands. Each transport element is associated with unique modeling approaches and uncertainties. Transpiration is perhaps the hardest to quantify as it is subject to all the variability of plant growth. Transpiration causes land area to lose moisture and the loss amount depends on precipitation incidence, the temperature and type and extent of vegetation. Plants can intercept virtually all recharge during the growing season and almost none from late fall to early spring in northeastern United States. Thus, an improvement in the transpiration element can contribute considerably to an improved groundwater …


Development Of Novel Bioelectrochemical Systems For In Situ Nitrate Removal From Groundwater, Yiran Tong Dec 2013

Development Of Novel Bioelectrochemical Systems For In Situ Nitrate Removal From Groundwater, Yiran Tong

Theses and Dissertations

This study aims to develop new approaches for in situ nitrate removal from groundwater by using bioelectrochemical systems (BES). BESs employ bioelectricity generated from organic compounds to drive nitrate moving from groundwater into the electrode chamber and reduce nitrate to nitrogen gas by heterotrophic denitrification. In first phase experiments, nitrate ions were driven into the anode chamber of a de-coupled reactor, whose electrode chambers were separated, where heterotrophic denitrification took place with organic reduction. It was proved that by applying additional electrical potential at 0.8V, the reactor could achieve highest removal rate of 208.2±13.3 g NO3--N/m3/d, when initial nitrate concentration …


Geochemistry And Inorganic Carbon Transport Of A Glacial Till Drumlin At A Road Salt Facility, Houbao Li Sep 2013

Geochemistry And Inorganic Carbon Transport Of A Glacial Till Drumlin At A Road Salt Facility, Houbao Li

Open Access Dissertations

Investigations were conducted at a salt/premix storage facility lying on top of a glacial drumlin near the coastline in eastern Massachusetts, to characterize salt contaminated groundwater. Groundwater hydrogeochemical variations at different depths were determined based on ten years of monthly or quarterly water quality data from 54 monitoring wells. Groundwater was grouped in three water categories – shallow, middle and deep. Hydrogeochemical characterization indicates that the dominant water types are Na-Cl, Na-Ca-Cl and Ca-HCO3 from the shallow to deep water group. Rock weathering is the dominant hydrogeochemical process for deep water group, whereas salt water percolation and cation exchange control …


Ozone And Gac Treatment Of A Central Florida Groundwater For Sulfide And Disinfectant By-Product Control, Tara Lamoureux Jan 2013

Ozone And Gac Treatment Of A Central Florida Groundwater For Sulfide And Disinfectant By-Product Control, Tara Lamoureux

Electronic Theses and Dissertations

This study evaluated the combination of ozone and granular activated carbon (GAC) treatment for the removal of sulfide and disinfection byproduct (DBP) precursors in drinking water at the pilot-scale. The research conducted was performed at the Auxiliary (Aux) and Main Water Treatment Plants (WTPs) in Sanford, Florida. Both WTPs rely upon groundwater sources that contain total sulfide ranging from 0.02 to 2.35 mg/L and total organic carbon (TOC) ranging from 0.61 to 2.20 mg/L. The Aux WTP’s raw water contains, on average, 88% more sulfide and 24% more TOC than the Main WTP. Haloacetic acids (HAA5) and total trihalomethanes (TTHMs) …


Microbiologically Enhanced Mixing Across Scales During In-Situ Bioremediation Of Uranium, Reinaldo E. Alcalde Dec 2012

Microbiologically Enhanced Mixing Across Scales During In-Situ Bioremediation Of Uranium, Reinaldo E. Alcalde

McNair Scholars Research Journal

Production of nuclear fuels for weapons and electric energy has resulted in groundwater uranium contamination at Department of Energy (DOE) sites. Reduction of uranium by dissimilatory metal-reducing bacteria (DMRB) is an effective approach for in-situ bioremediation of these sites. In this process, an organic electron donor is typically delivered through a well into groundwater in order to promote the biological reduction of soluble and toxic U(VI) to insoluble and less toxic U(IV). A key challenge is mixing the organic electron donor with U(VI) in groundwater where laminar flow conditions prevail. A potential solution is to enhance reaction beyond the scale …


Evaluation Of An On-Line Device To Monitor Scale Formation In A Brackish Water Reverse Osmosis Membrane Process, Jennifer C. Roque Jan 2012

Evaluation Of An On-Line Device To Monitor Scale Formation In A Brackish Water Reverse Osmosis Membrane Process, Jennifer C. Roque

Electronic Theses and Dissertations

A modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city of Sarasota’s Public Works and Utilities (City) water treatment facilities located in Sarasota, Florida. During the time-frame of this study, the City was in the process …


Implications Of Surface Runoff Recharge In Semi-Arid Regions On Groundwater Sustainability, Omar M. Al-Qudah Jan 2011

Implications Of Surface Runoff Recharge In Semi-Arid Regions On Groundwater Sustainability, Omar M. Al-Qudah

Open Access Theses & Dissertations

Amargosa Desert, Nevada regional groundwater studies show that the surface runoff infiltration occurring in the arroyos following runoff producing storms, and this infiltration is considered to be a major source of groundwater recharge. Groundwater infiltration through alluvium was investigated in the Amargosa Desert using borehole drill cuttings, groundwater chemistry, and applying a novel method for collecting runoff water. The sampling process included sediment, precipitation, and runoff water. In total, 176 runoff, 182 sediment, and 45 precipitation samples were collected between January, 2009 and January, 2011.Water chemistry, chloride concentrations, and stable isotopes of water collected from specially designed runoff samplers, placed …


Low Impact Development (Lid) Structures For Groundwater Management And Watershed Protection In The Amrc10 Watershed, El Paso Texas, Ricardo Sabino Marmolejo Jan 2010

Low Impact Development (Lid) Structures For Groundwater Management And Watershed Protection In The Amrc10 Watershed, El Paso Texas, Ricardo Sabino Marmolejo

Open Access Theses & Dissertations

The AMRC10 watershed was modeled in HEC-HMS and in Green Values. Theoretical storm water conveyance and capture models were tested in these programs along with several Low environmental Impact Development features to determine their applicability and performance at this site. Lots should all be designed with all roof downspouts draining into raingardens, at least half of all lawns should be natural landscaping using local vegetation, porous pavement should be used for all driveways, sidewalks and non-street pavement and drainage to the stormwater conveyance structures should make use of drainage swales instead of storm water pipes. To manage runoff three detention …


Control Of Hydrogen Sulfide From Groundwater Using Packed-Bed Anion Exchange And Other Technologies, Camilo Romero Cotrino Apr 2006

Control Of Hydrogen Sulfide From Groundwater Using Packed-Bed Anion Exchange And Other Technologies, Camilo Romero Cotrino

USF Tampa Graduate Theses and Dissertations

Hydrogen sulfide imparts odors and taste to drinking water and can be corrosive to distribution systems. Groundwater sources used to produce drinking water tend to have sulfide concentrations ranging from below 0.1 to over 3 mg/L. Under anaerobic conditions, hydrogen sulfide can be formed from reduction of sulfate and elemental sulfur through chemical or biological reactions. Therefore, to decrease the potential for hydrogen sulfide in water systems, control of all forms of sulfur should be consistent.

Hydrogen sulfide in groundwater can be controlled through conversion or removal mechanisms. Conversion reactions result from chemical or biological reactions that oxidize hydrogen sulfide …


Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng Jan 2005

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …