Master of Science (MS), Ohio University, 2020, Environmental Studies (Voinovich)

Ground source heat pumps (GSHPs) have been used for heating and cooling applications in areas where the thermal gradients are normal. Unlike conventional heating and cooling systems, ground source heat pumps rely on ground or underground water temperature which is more constant than air temperature. Abandoned underground coal mines (AUMs) have been used as heat exchangers for ground source heat pumps in countries such as Nova Scotia, the Netherlands and states like Pennsylvania. Ohio has around 147 abandoned underground mines located close to towns and with sufficient water and heat available in the groundwater for heat exchange using ground source heat pumps. This project characterizes the potential of the AUM AS-029 located in Athens, Ohio, as a reservoir for GSHP technology in Ohio University or The Plains. Monitoring of the hydraulic and thermal response of groundwater wells around the mine was performed and a hydrogeological model was constructed in Visual MODFLOW to better understand the flow of water through the mine. Additionally, a thermal model of the mine was created considering the overburden thickness of the mine. Three monitoring wells were studied, one to the north of the mine and 2 to the South in The City of Athens well field in the Hocking River valley. Groundwater in the 4 wells respond to precipitation and changes in ambient temperature with a higher response in the wells with lower depth. One of the City of Athens wells, A10, has an unusual response with a high conductivity due to a nearby underground salt deposit. Ground water modeling and modeling of the heat absorbed by the mine shows that mine AS-029 can be used to receive heat, it cannot be used to give heat due to the low temperature of the groundwater in this area. The volume of water that circulates through the mine is not easily exchanged since only 0.03% is exchanged every day and it takes 2,900 days to substitute 100% of the water within the mine. For a change in temperature in the mi (open full item for complete abstract)

Committee: Dina López Dr. (Advisor); Natalie Kruse Daniels Dr. (Committee Member); Daniel Che Dr. (Committee Member) Subjects: Energy; Environmental Geology; Environmental Science; Environmental Studies; Geology; Hydrologic Sciences; Hydrology

Master of Science (MS), Ohio University, 2012, Geological Sciences (Arts and Sciences)

The aquifer that supplies the Newport Wellfield in Ohio is contaminated with trichloroethylene and its daughter products dichloroethylene and vinyl chloride. These toxic organic compounds were introduced into the aquifer during the 1960s and 1970s when local industries donated their waste products to the local volunteer fire department that used the chemicals in training exercises. This study characterized the groundwater flow and transport of trichloroethylene, dichloroethylene, and vinyl chloride in the aquifer. Groundwater flow and plume migration were investigated through modeling analyses of site-specific geologic, pump test, and contaminant concentration data using AQTESOLV, Hydro GeoBuilder, and Visual MODFLOW. Based on model results, the uncontaminated production wells will not become contaminated in the future. Under the current pumping scheme, the aquifer will not meet MCL requirements for 6.5 years. Finally, this time could be reduced to less than 3 years if the pumping rate of the contaminated well is increased to 140 gpm and it is pumped continuously.

Committee: Eung Seok Lee (Advisor); Elizabeth Gierlowski-Kordesch (Committee Member); Douglas Green (Committee Member); David Hunt (Committee Member) Subjects: Geology