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Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro
Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro
Theses and Dissertations
In 1960 at the McGuire Air Force Base, New Egypt, New Jersey a helium tank ruptured causing a fire to ignite a nearby nuclear tipped Boeing Michigan Aeronautical Research Center (BOMARC) missile. During the fire the weapons grade plutonium (Pu- 239, Pu-240, and Pu-241) ignited and was released into the surrounding area, due to both firefighting efforts, where high pressure water was used to put out the fire, as well as smoke that deposited plutonium as oxidized particles in the surrounding area (Cicotte, 2007). This study investigates the heterogeneity of the distributed plutonium contamination in the McGuire Air Force Base …
Substrate Availability In Solid Waste Landfills, Brian D. Benter
Substrate Availability In Solid Waste Landfills, Brian D. Benter
Theses and Dissertations
Numerous models exist to both predict and represent the many biological activities that occur in the modern landfill. These different models use varying methods of characterizing what is happening, what is thought to happen, or what should be happening based on both empirical data and theoretical reasoning. The model presented here is an extension of the system dynamics model originally presented by Colborn in 1997. The revamped model presents a different perspective on what happens as solid organic waste is transformed to simpler substances. This new view involves a bacterial population performing hydrolysis whose growth is limited by the amount …
Modeling Uptake And Translocation Of Lead (Pb) In Maize For The Purposes Of Phytoextraction, Mark A. Brennan
Modeling Uptake And Translocation Of Lead (Pb) In Maize For The Purposes Of Phytoextraction, Mark A. Brennan
Theses and Dissertations
Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. This technology has the potential to decrease the costs of remediating contaminated sites by several orders of magnitude compared to traditional technologies. To effectively implement this technology requires an understanding of the plant processes that control uptake and translocation of metals from the soil. Currently these processes are poorly understood, and especially so for Pb. The purpose of this thesis was to gain insights concerning the plant mechanisms that control uptake and translocation of Pb and how these mechanisms interact to control levels of Pb accumulation …
Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman
Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman
Theses and Dissertations
Laser-induced breakdown spectroscopy (LIBS) is a spectroscopic technique where output from a pulsed laser is focused onto a target in order to create an intense plasma. The optical emission is characteristic of the elements in the focal volume and can be used for elemental analysis. Research on the detection of nickel in solution in addition to solvent detection of CCl4, CHCl3, C2Cl4, and C2HCl3 has been performed. Breakdown was formed at the sample surface via a Q-switched Nd:YAG laser. Initially, operation of the laser was at 1064 nm/repetition rate of 5 Hz. Experiments …
Study Of Desorption Of Contaminant From Synthetic Soil, Kung-Fu Hwang
Study Of Desorption Of Contaminant From Synthetic Soil, Kung-Fu Hwang
Theses and Dissertations
A better understanding of sorption and desorption processes could improve estimates of time and cost required for remedial activities, exposure times and health risk, and bioavailability. Conventional rate-limited sorption models do not accurately define the diffusion domain at the grain scale. Heyse (1994) proposed the multiple sites in series (MSS) model, which allows more general description of the geometry of the sorption domain than the classical spherical or discrete distributions. A version of this model was tested by deVenoge (1996). The model was able to accurately simulate sorption rate data, but could not estimate unique geometry parameters. This research is …
Experiment Using Infrared Spectroscopy To Study The Effect Of Soil Characteristics Upon The Rate Of Trichloroethylene Desorption, Benjamin T. Kindt
Experiment Using Infrared Spectroscopy To Study The Effect Of Soil Characteristics Upon The Rate Of Trichloroethylene Desorption, Benjamin T. Kindt
Theses and Dissertations
This research investigated the influence of soil characteristics on the desorption of trichloroethylene (TCE). TCE is one of the most common contaminants at Superfund sites. Unfortunately, extraction of TCE from contaminated soils has been hindered by its slow and poorly understood desorption from soil particles. The rate and progress of desorption of TCE from seven types of soil with varying particle diameters and elemental compositions was measured using optical absorption techniques. Fitting the data to the Langmuir Isotherm functional form predicted in the literature yielded parameters for the desorption rate and total amount desorption each soil type. These parameters were …
Use Of Infrared Spectrometry To Determine The Effect Of Temperature On The Description Rates Of Trichloroethylene From Plastic Clay 98b, Abdellatif Fares
Use Of Infrared Spectrometry To Determine The Effect Of Temperature On The Description Rates Of Trichloroethylene From Plastic Clay 98b, Abdellatif Fares
Theses and Dissertations
This thesis investigated the influence of temperature on the desorption rated of trichloroethylene (TCE) from plastic clay. It was expected that an increase in temperature will cause an increase in both the desorption rates of TCE and in the desorbed quantity. Previous studies on other chemicals indicated a faster decrease in the remaining sorbed concentration with an increase in temperature. This research made use of the infrared optical absorption technique. IR spectroscopy was used to measure the concentration of the vapor TCE that desorbed from the soil. The soil was exposed to liquid TCE for 2 days then placed inside …
Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma
Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma
Theses and Dissertations
This laboratory based thesis investigated the desorption rate of trichloroethylene (TCE) from flint clay while varying the resident time of TCE exposed to the clay. It is thought that in long contaminated soil, a majority of contaminant mass will become entrained within the interior of the soil particles to slowly desorb out of the soil over long periods of time. Recent studies suggest that the longer a contaminant is resident in soil, the longer the contaminant will take to desorb from the soil. To understand more about soil desorption, this experiment was developed using infrared spectroscopy to detect TCE vapor …
An Analysis Of Site Parameters Affecting Natural Attenuation In Saturated Soil, William H. Potts
An Analysis Of Site Parameters Affecting Natural Attenuation In Saturated Soil, William H. Potts
Theses and Dissertations
This study investigated the natural attenuation mechanisms and some of the parameters affecting those mechanisms in the saturated zone. A literature search revealed numerous studies of various attenuation and the associated parameters. Much of the literature emphasized biodegradation as the most promising attenuation mechanism. BIOPLUME II(TM), a fate and transport model, was used to simulate the fate and transport of contaminant plume. The effects of the model parameters were investigated by observing the distance a contaminant plume was expected to migrate over a fifty year period. The investigation was limited by the model which excludes chemical reactions and some physical …