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In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland
In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland
Theses and Dissertations
The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater remediation objectives. One inn9vative technology that is currently under development involves metal reductants or catalysts to chemically destroy the dissolved chlorinated solvent. Models are important tools that can be used to help transition this technology to the field. Model studies can be used to gain understanding about the technology, help determine when the prospective technology might work for a given site, and design full-scale field applications.
Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox
Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox
Theses and Dissertations
Air Force aircraft-painting operations create clouds of paint overspray that contain strontium chromate, a confirmed carcinogen, which poses an exposure hazard to painters. It is often assumed that all particles in paint overspray have the same chemical composition as the original paint mixture, however differences in composition may occur in various particle sizes. Because particle size affects where in the respiratory system a particle deposits, actual exposures to a specific chemical may vary. Paint particles greater than 2.5 µm are deposited in the upper respiratory system and will be eliminated by physiological removal mechanisms. Particles less than 2.5 µm will …
Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar
Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar
Theses and Dissertations
The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethylene, or carbon dioxide (CO2), within the confines of a constructed wetland. A system dynamics approach will be used. This model is focused on identifying and optimizing the naturally occurring processes in stratified wetland sediment that reduce mass, toxicity, mobility, volume or concentration of contaminants in groundwater. Contaminant fate and transport within a wetland system is extremely complex and the mechanisms that drive wetland behavior are dynamic. Confidence in the model was built through verification and testing. Reasonable …
Modeling The Effect Of Nonlinear And Rate-Limited Sorption On The Natural Attenuation Of Chlorinated Ethenes, Peter P. Feng
Modeling The Effect Of Nonlinear And Rate-Limited Sorption On The Natural Attenuation Of Chlorinated Ethenes, Peter P. Feng
Theses and Dissertations
Chlorinated solvents like tetrachloroethene (PCE) and trichloroethene (TCE) are the most common detected groundwater contaminants at Department of Defense installations in the United States. Unfortunately, technologies conventionally used to remediate chlorinated solvent-contaminated groundwater often fall short of achieving regulatory goals. Natural attenuation of chlorinated solvents offers an alternative remediation strategy that may achieve goals. However, the processes involved with natural attenuation are not fully understood, and this lack of understanding has hindered acceptance of natural attenuation by regulatory agencies. This study involved use of a numerical model that incorporated the physical, chemical, and biological processes thought to be relevant to …
Analysis Of The Air Force Iso 14001 Pilot Study Conducted By Dod, Rodney C. Harris
Analysis Of The Air Force Iso 14001 Pilot Study Conducted By Dod, Rodney C. Harris
Theses and Dissertations
The Department of Defense (DoD) conducted an ISO 14001 pilot study with the primary goal of determining how ISO 14001 could help DoD organizations reduce risks, improve compliance with environmental regulations, enhance stewardship, contain costs, and meet emerging regulatory requirements. This thesis analyzed the pilot study, specifically looking at the ISO 14001 implementation at three Air Force installations participating in the study. The research objectives were to identify factors that affect implementation of ISO 14001, compare the implementation strategies used by the bases, and develop propositions for Air Force managers to consider when implementing ISO 14001. Interviews of key personnel, …
Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell
Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell
Theses and Dissertations
Maintaining safe flight operations, military and civilian, in cold weather requires the use of de-icing fluids. Glycols, the primary component of de-icers, have been extensively studied. Water and additives such as corrosion inhibitors and other performance enhancing chemicals make up the remaining portion of de-icing fluids. Little research has been conducted on the additives, but several are suspected toxins to microorganisms, therefore the EPA regulates the disposal of spent de-icing fluids. Tolyltriazole, a corrosion inhibitor found in de-icing fluids, is a suspected human carcinogen. It is also known to be moderately toxic to microorganisms based on Microtox results. The purpose …