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Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman
Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman
Theses and Dissertations
The purpose of this study is to determine chlorinated solvent contamination levels in an upward flow constructed wetland at Wright-Patterson Air Force Base (WPAFB), Ohio. A stratified grid sampling methodology will be used in sampling the contaminated groundwater. Analysis will be accomplished by means of purge-and-trap gas chromatography. The contaminant concentration levels will be used to enhance the design and construction of man-made wetlands used to remove chlorinated solvents from aquifers. PCE levels declined from an average of 33.97 ppb in the inflow stream to an average of 3.65 ppb in the upper layer, a 91% reduction. High concentrations occurred …
An Anion Characterization Of A Constructed Wetland Used For Chlorinated Ethene Remediation, Bradley M. Bugg
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 …
Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh
Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh
Theses and Dissertations
This study examines the flow of groundwater through one of the treatment cells. A major goal of the study is to determine whether the system design facilitates uniform vertical flows through the subsurface soil sediments or if preferential flows occur. Conceptually, uniform flows will achieve the most efficient degree of contaminant removal possible by evenly dispersing the groundwater contaminants throughout the full volume of the subsurface media. A three-dimensional grid of piezometers is used to generate potentiometric contour maps, and in-situ tests of hydraulic conductivity facilitate construction of a numerical computer model. The contours of hydraulic head, measured conductivities, and …
A Comparison Of Modeling Approaches In Simulating Chlorinated Ethene Removal In A Constructed Wetland By A Microbial Consortia, Jason S. Campbell
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 …