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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2002

Environmental Sciences

Theses and Dissertations

Articles 1 - 7 of 7

Full-Text Articles in Physical Sciences and Mathematics

Determining The Mobility Of Metals Through Coal Combustion Byproducts In Surface Impoundments By Analyzing Leachate From Modified Saturated Hydraulic Conductivity Tests, Michael Joseph Trofinoff Dec 2002

Determining The Mobility Of Metals Through Coal Combustion Byproducts In Surface Impoundments By Analyzing Leachate From Modified Saturated Hydraulic Conductivity Tests, Michael Joseph Trofinoff

Theses and Dissertations

Surface impoundments are used extensively throughout the utility industry to store the combustion byproducts, or ash, from coal-fired generating facilities. Following combustion, the metals, naturally contained within coal at low concentrations, may become highly concentrated within the ash. These combustion byproducts are then piped out in a water-ash slurry to the surface impoundments where the ash weathers to- a clay- like substance after approximately 10 years. It is feared that these metals that are contained within the ash could possibly leach into the ground and contaminate the local groundwater. Utilizing a open column percolation test to determine the hydraulic conductivity …

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Using The Index Of Biotic Integrity Of Fish Communities To Evaluate Habitat Quality In Middle Chattahoochee River Tributaries, Theodor W. Roever Aug 2002

Using The Index Of Biotic Integrity Of Fish Communities To Evaluate Habitat Quality In Middle Chattahoochee River Tributaries, Theodor W. Roever

Theses and Dissertations

An ichthyological survey was conducted within the lower Piedmont and upper Coastal Plain physiographic regions of the middle Chattahoochee River drainage basin between August 1998 and September 2000. Sampling was conducted by Columbus State University (CSU) under contract to Columbus Water Works for the purpose of obtaining biological measurements of watershed health. Objectives of the survey were the establishment of a data baseline of IBI scores for this ecoregion and to ascertain if there was a correlation between the IBI score and human influence. The thesis to be tested is: 'Fish community IBI scores of different watersheds within the Middle …

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Using Gis And Land Use Data To Select Candidate Reference Sites For Stream Bioassessment, John Robert Olson May 2002

Using Gis And Land Use Data To Select Candidate Reference Sites For Stream Bioassessment, John Robert Olson

Theses and Dissertations

GIS was used to select candidate reference sites in Georgia to characterize the reference condition by sub-ecoregion for a rapid bioassessment of streams statewide. Instead of relying on best professional judgment or previous knowledge of a limited number of sites, we performed an objective evaluation of cumulative impact on all catchments using land use data sets. These included road and impoundment data from DLGs and Multi-Resolution Land use Consortium data. Land use impairment was measured as percentages of forest, urban, pasture, row crops, and barren area for both the entire catchment and for 10, 40, and 130-m riparian buffers, road …

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An Anion Characterization Of A Constructed Wetland Used For Chlorinated Ethene Remediation, Bradley M. Bugg Mar 2002

An Anion Characterization Of A Constructed Wetland Used For Chlorinated Ethene Remediation, Bradley M. Bugg

Theses and Dissertations

Chlorinated ethenes physical properties as well as its ubiquitous state at DOD installations makes it a priority for innovative remediation efforts. Current techniques are expensive and time consuming to maintain. Constructed wetlands suggest an inexpensive and operational alternative to conventional technologies. Sub-surface flow wetlands provide the anaerobic zones necessary to reduce the recalcitrant chlorinated solvents prior to anaerobic or aerobic mineralization of its daughter products. A vertical flow cell to include sequential sedimentary layers of two hydric soil lifts and a mix of hydric soil and woody compost was the subject of this investigation. This study focused on the statistical …

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A Comparison Of Modeling Approaches In Simulating Chlorinated Ethene Removal In A Constructed Wetland By A Microbial Consortia, Jason S. Campbell Mar 2002

A Comparison Of Modeling Approaches In Simulating Chlorinated Ethene Removal In A Constructed Wetland By A Microbial Consortia, Jason S. Campbell

Theses and Dissertations

The purpose of this study is to compare different approaches to modeling the reductive dechlorination of chlorinated ethenes in the anaerobic region of an upward flow constructed wetland by microbial consortia. A controlled simulation experiment that compares three different approaches to modeling the degradation of chlorinated ethenes in wetland environments is conducted and investigates how each of the modeling approaches affect simulation results. Concepts like microbial growth in the form of a biofilm and spatially varying contaminant concentrations bring the validity of the CSTR assumption into question. These concepts are incorporated into the different modeling approaches to evaluate the CSTR …

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Chromate Content Bias Versus Overspray Particle Size In Three Aircraft Primer Paints, Brian S. Rhodes Mar 2002

Chromate Content Bias Versus Overspray Particle Size In Three Aircraft Primer Paints, Brian S. Rhodes

Theses and Dissertations

The United States Air Force relies on the corrosion inhibiting properties of chromate-containing primer paints to protect the aluminum skin of its aircraft. Hexavalent chromium (Cr6+) the ingredient responsible for the corrosion inhibiting characteristics of these primers is a known human carcinogen. The concentration of Cr6+ in different particle sizes of paint overspray is important to understand health implications to painters as well as filtration efficiency. Previous research indicates disproportionately less Cr6+ content in smaller particles collected in the overspray of solvent-based epoxy-polyamide paint primers (MIL-P-2377G). This research explores the possibility of a particle size bias …

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Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Perchlorate Contaminated Groundwater, Jeffrey C. Parr Mar 2002

Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Perchlorate Contaminated Groundwater, Jeffrey C. Parr

Theses and Dissertations

Groundwater contamination by perchlorate has recently been recognized as a significant environmental problem across the United States, and especially at Department of Defense facilities. In this study, a model is used to evaluate the potential of a innovative in situ bioremediation technology using Horizontal Flow Treatment Wells (HFTWs) to manage perchlorate-contaminated groundwater. The technology uses HFTWs to mix an electron donor into perchlorate-contaminated groundwater in order to promote reduction of the perchlorate by indigenous microorganisms in bioactive zones within the aquifer, as well as recirculate the contaminated water between treatment well pairs to achieve multiple passes of contaminated water through …

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