Pilot-Scale In-Situ Biosequestration of Uranium in Groundwater at the Monument Valley Umtra Site
Publisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.Abstract
In-situ biosequestration, wherein electron-donating substrates are injected to promote microbial-associated sequestration of contaminants, is one promising enhanced-attenuation technique for remediation of groundwater containing arsenic, uranium, selenium, and similar constituents. A pilot-scale test of in-situ biosequestration for uranium in groundwater is in progress at a former uranium mining site in Monument Valley, Arizona. Approximately 20 m3 of 0.5% ethanol solution was injected into a test zone of the alluvial aquifer. Groundwater was sampled periodically before, during, and after the injection. The relevant constituents, such as uranium, nitrogen species, sulfur species, anions/cations, ethanol, and sulfur and nitrogen isotopes, were monitored to characterize the biosequestration process. Sediment samples were also collected before and twice after the injection for monitoring change in sediment properties, mineral geochemical composition, microbial community composition, and microbial activity. The results of the test are compared to those of a prior test conducted at a different location of the site to evaluate the impact of water-quality parameters on sequestration effectiveness.Type
textElectronic Thesis
Degree Name
B.S.Degree Level
bachelorsDegree Program
Honors CollegeEnvironmental Sciences