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Full-Text Articles in Environmental Monitoring
Influence Of Physical Variability Of Highly Weathered Sedimentary Rock On Nitrate In Area 3 Of The Enigma Field Research Site At Y-12, Erin Kelly
Masters Theses
Uranium processing and waste storage in unlined waste ponds leached contaminants into the groundwater at Y-12, Oak Ridge, Tennessee, from the 1950s to 1980s. Groundwater wells near the S-3 ponds have had the highest nitrate concentrations of groundwater anywhere in the world (>10,000 mg/L). For reference, the maximum contaminant level for nitrate in drinking water set by the U.S. Environmental Protection Agency is 10 mg/L. Since 2012, the ENIGMA (Ecosystems and Networks Integrated with Genes and Molecular Assemblies) group has been characterizing, monitoring, and conducting field experiments to understand the interactions between contaminants, microbes, and the subsurface. The goals …
Characterizing Groundwater Ch4 And 222rn In Relation To Hydraulic Fracturing And Other Environmental Processes In Letcher County, Ky, St. Thomas Majeau Ledoux
Characterizing Groundwater Ch4 And 222rn In Relation To Hydraulic Fracturing And Other Environmental Processes In Letcher County, Ky, St. Thomas Majeau Ledoux
Masters Theses
Hydraulic fracturing of shale deposits has greatly increased the productivity of the natural gas industry by allowing it to exploit previously inaccessible reservoirs. However, previous research has demonstrated that this practice can contaminate shallow aquifers with CH4 [methane] from deeper formations. This study compares concentrations and isotope compositions of CH4 sampled from domestic groundwater wells in Letcher County, Kentucky in order to characterize its occurrence and origins in relation to neighboring hydraulically fractured natural gas wells. Additionally, this study tests the reliability of 222Rn [radon] as an alternative tracer to CH4 in identifying processes of gas …
Mussel Survivorship, Growth Rate And Shell Decay Rate In The New River Basin Of Tennessee: An Experimental Approach Using Corbicula Fluminea, Grant Andrew Mincy
Mussel Survivorship, Growth Rate And Shell Decay Rate In The New River Basin Of Tennessee: An Experimental Approach Using Corbicula Fluminea, Grant Andrew Mincy
Masters Theses
The New River Basin (NRB) of Tennessee is home to a number of rare endemic aquatic communities. One such community of particular importance to the area, experiencing a precipitous population decline due to the fouling and pollution of their freshwater systems, is that of freshwater mussels (Bogan 2006). This study in the NRB involves measuring the mortality rates of live Asian clams (Corbicula fluminea) assemblages and the shell decay rates of their death assemblages. This study also examines the decay rates of the native Villosa iris to gather information on molluscan health and the ability of their shells …
The Effects Of Changes In Water Content On Uranium(Vi) Leaching In Sediment Mixtures Containing Gravel, Andrew Weber Moore
The Effects Of Changes In Water Content On Uranium(Vi) Leaching In Sediment Mixtures Containing Gravel, Andrew Weber Moore
Masters Theses
This study is aimed at understanding the physical and chemical effects that changes in water content have on uranium leaching in sediment containing gravel. It was hypothesized that leaching will be more efficient under unsaturated conditions because flow will be restricted to the smallest pores and will have the most contact with the uranium contaminated sediment. Under saturated conditions, a large portion of the flow will bypass the < 2 mm material, and in turn not come into contact with uranium contaminated material. Batch adsorption and desorption experiments were performed on < 2 mm ERDF sediment to determine the linearity and reversibility of sorption processes and to aid in the interpretation of the leaching experiments. Results of the desorption experiments on aged, contaminated sediments show that the mass percent of sorbed U(VI) released to solution decreased as the sorbed concentration of U(VI) decreased. The opposite trend was observed on freshly contaminated sediments. This indicated that aging increased U(VI) affinity for the solid phase and was attributed to either the crystallization of calcite, which incorporated a portion of the sorbed U(VI) as it crystallized, or the presence of voids in basaltic lithic fragments accessed by diffusion. Column leaching experiments were performed at two water contents on artificially contaminated sediment collected from the Department of Energy’s (DOE) Hanford Site, Washington state. The sediment contained 81.3% gravel (> 2 mm) by mass. Non-reactive tracers were well fit with the convection-dispersion equation (CDE) at both high and low water contents indicating physical equilibrium. The column experimental data were fitted to an …