Master of Science (MS), Ohio University, 2017, Environmental Studies (Voinovich)

Hydraulic fracturing is an industry that has expanded quickly in the United States and around the world. Over the past years, salt waste water from these operations has been injected to the ground. The salt water is not only containing a high amount of salt, it is also containing a mixture of proppants, and other harmful substances which have potential risks and are toxic to public health, wildlife, and the environment. Produced water or waste fluid that came from hydraulic fracturing should be properly handled and disposed to protect the environment and human health. This study is focused on a study of a water quality alert system able to detect brine spills by using a low-cost technology. The water quality alert system is being developed especially in remote areas where it is not always feasible to monitor the quality of the water. The brine spill alert system is based on using Atlas Scientific temperature and conductivity sensors and deploy them downstream of Class II injection wells. The data collection from the probes is transmitted to the Ohio Voinovich campus server using a cellular network to upload the data bundles into the Mongolab cloud database. Testing has demonstrated an accuracy within 5-10% of reading from the calibrated commercial meter in laboratory conditions. Calibration for the EC sensor is necessary for every 5 days; meanwhile, the temperature sensor required a weekly calibration based on field data; however, additional investigation is necessary. Modeling the mixing of fracking fluids with river water using PHREEQCi software demonstrated that a brine spill mixing with a stream in a ratio of 1:99 trigger the alert threshold of 1500 µS/cm during summer and winter seasons.

Committee: Natalie Kruse (Advisor); Dina Lopez (Committee Member); Hans Kruse (Committee Member) Subjects: Environmental Studies

Master of Science (MS), Ohio University, 2016, Geological Sciences (Arts and Sciences)

Constructed wetlands are one of the effective wastewater treatment systems which have been utilized since 1950s. Characterizing landfill leachate and monitoring the treatment system are important for operation and development of the system. The objectives of this study were to delineate hydrologic and chemical processes occurring in the constructed wetland which has been treating landfill leachate from Athens 691 Landfill in Ohio since 1996. The treatment system consisted of six wetland cells. The leachate has high levels of BOD5, COD, ammonia, and metals, and low pH and low DO. Field parameters, inflow and outflow rates between wetland cells, and water isotopes were measured monthly to monitor water quality, flow, and storage change. The storage change in each month was corresponded to inflow and outflow rates. Seasonal water samples were collected from the wetland cells and analyzed for water chemistry and water isotopes to evaluate removal efficiencies. The results indicate that the average removal efficiencies of iron, manganese, ammonia, and sulfate were 99 %, 94 %, 84 %, and 69 %, respectively. The results from PHREEQCI indicated that iron and sulfide minerals were precipitating. The modeled data were in keeping with the observed metal concentrations which were decreasing as the water flows through the treatment cells. The removal efficiencies of ammonia, nitrate, BOD5, and COD were influenced by the seasonal variations of water temperature which constrains biological processes. Results of this study suggest that the constructed wetland could provide efficient and long-term option for treating landfill leachate in cost effective manner.

Committee: Eung Seok Lee (Advisor) Subjects: Environmental Geology; Geology; Hydrology

Master of Science (MS), Ohio University, 2014, Geological Sciences (Arts and Sciences)

The Hewett Fork watershed in Southeastern Ohio is impacted by AMD from the AS-14 mine complex in Carbondale, Ohio. In attempts to remediate the stream, the water is being treated with continuous alkaline input from a calcium oxide doser. While the section of watershed furthest downstream from the doser is showing signs of recovery, the water chemistry and aquatic life near the doser are still impacted. The objectives of this study are to evaluate the alkalinity and acidity budgets of the main stem of the stream and examine and model the chemistry of main stem and the tributaries of Hewett Fork. By examining the inputs of tributaries into the main stem, the project aims to understand processes occurring during remediation throughout the entire stream system. Chemical analysis of water and sediment samples, XRD identification of minerals, and geochemical modeling using the PHREEQCI program have been applied to understand the chemical processes happening in the Hewett Fork watershed. Results show that the minerals ferrihydrite, goethite, calcite, diaspore, gibbsite, and gypsum form when the acidic waters mix with CaO in equilibrium with CO2 and O2 in the air, transferring the contaminants from the water to the sediments. While these processes contribute to improvements in water chemistry, the precipitation and deposition of metals inhibits biological recovery downstream of the doser. When examining the recovery of an acid mine drainage remediated stream, the inputs of contaminants, the transport of sediments, and the complex reactions between the water and sediments need to be considered together to understand how the variations in stream chemistry affect the biology of the stream.

Committee: Dina Lopez (Advisor); Natalie Kruse (Committee Member); Elizabeth Gierlowski-Kordesch (Committee Member) Subjects: Environmental Geology; Geochemistry