Engineering Commons^™

High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

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Atmospheric carbon dioxide (CO₂) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO₂ concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO₂ concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …

Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer, Riley Blais

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Pumping tests with sinusoidal variation in pumping rate have been proposed as a method for improving aquifer characterization. These tests can interrogate a larger aquifer volume than slug tests and they can be more sensitive to small variations in drawdown. Current methods of using sinusoidal variations of rate are based on measuring pressure signals from the reservoir or aquifer, which requires access to monitoring wells. An alternative approach has been developed that measures the strain in the vadose zone instead of pressure in the reservoir. An instrument has been developed at Clemson University that can measure small strains using optical …

Geology-Based Shear-Wave Velocity Model Of Reference Site Conditions In South Carolina For Seismic Site Response Analysis, Camilius Amevorku

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Assessing earthquake hazard in the State of South Carolina is important because it is one of the most seismically active regions of the eastern United States and has experienced earthquakes of damaging levels in the historical past. Examples of these damaging seismic events are the 1886 Charleston earthquake (M 6.7 to 7.5) and the 1913 Union County earthquake (M 4.5 to 5.5).

Small-strain shear-wave velocity (V_S) is an important parameter in performing site response analysis. The deep nature of the top of reference firm rock (i.e., V_S ≥ 760 m/s or B-C boundary) due to …

Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome

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Current biological strategies for remediating trichloroethylene (TCE) in low pH aquifers (i.e., pH14C-TCE assay was developed to determine pseudo first-order rate constants for the degradation of TCE in microcosms containing soil and groundwater from the Boeing Michigan Aeronautical Research Center (BOMARC) superfund site, where the pH ranges from 4.1 to 4.9. The ¹⁴C-TCE assay was also adapted to calculate soil-normalized rate constants for data from this site, as well as data that Szwast²¹ collected from the Beltsville Agricultural Research Center (BARC). In addition to natural attenuation, biostimulation through amendments of methane and nutrients were also assessed. This treatment …

Transformation Of Uranium In A Geological Environment, Derrell Hood

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Incorporation of uranium into iron oxide minerals is a promising mechanism for the environmental immobilization of U(VI). In this study, synthesized hematite was doped with uranium and analyzed with SEM-EDS, TEM, XRD, and ICP-MS. The results of this analysis strongly indicate uranium incorporation into the mineral, as well as the possible presence of a co-precipitated uranium mineral clarkeite. Preliminary results also shows an increase in the amount of uranium associated with the hematite particles as a function of mineral aging. Cyclic Voltammetry (CV) was used to induce and characterize electrochemical changes of uranium in the doped hematite system; these changes …

Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng

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Solar thermal energy is taking up increasing proportions of future power generation worldwide. Thermal energy storage technology is a key method for compensating for the inherent intermittency of solar resources and solving the time mismatch between solar energy supply and electricity demand. However, there is currently no cost-effective high-capacity compact storage technology available (Bakker et al., 2008). The goal of this work is to propose a high temperature subsurface thermal energy storage (HSTES) technology and demonstrate its potential energy storage capability by developing a solar-HSTES-electricity generation system. In this work, main elements of the proposed system and their related state-of-art …