Carbon tetrachloride (CT) and chloroform (CF) were transformed in batch reactor experiments conducted with anaerobic dechlorinating cultures and supernatant (ADC+S) harvested from continuous flow reactors. The Evanite (EV-5L) and Victoria/Stanford (VS-5L) cultures capable of respiring trichloroethene (TCE), 1,2-cis-dichloroethene (cDCE), and vinyl chloride (VC) to ethene (ETH) were grown in continuous...
Due to the effective antimicrobial properties of silver nanoparticles they represent a significant proportion of all consumer-‐related nanomaterials. The introduction of silver nanoparticles from these products into domestic and industrial wastewater streams poses potential complications for biological treatment systems. A critical component of biological treatment that is extremely sensitive to...
Methanotrophic bacteria are promising means of producing value-added products as they have the ability to transform methane under atmospheric temperature and pressure. Efforts to develop methanotrophs to produce value-added products are hoped to incentivize a decrease in methane flaring operations. The data collected during this study was used to inform...
This study investigated the use of radon-222 as an in situ partitioning tracer for quantifying nonaqueous phase liquid (NAPL) saturations in the subsurface. Laboratory physical aquifer models (PAMs), field experiments, and numerical simulations were used to investigate radon partitioning in static (no-flow) experiments and in single-well, 'push-pull' tests conducted in...
This dissertation explores the physiology and gene expression of the ammonia-oxidizing bacterium Nitrosomonas europaea in surface-associated bacterial communities, or biofilms. Biofilms of N. europaea were cultivated in drip flow reactors for several weeks and gene expression microarrays were used to detect 240 genes differentially expressed between the mature biofilms and...
This thesis explores the factors limiting the alkene substrate range of the vinyl chloride (VC)-utilizing bacteria, and describes a method for measuring VC transformation in situ. Vinyl fluoride (VF) was evaluated as a surrogate for monitoring aerobic VC-transformation utilizing three isolates, Mycobacterium EE13a, Mycobacterium JS60 and Nocardioides JS614. JS614 grew...
This research focuses on the anaerobic transformation of trichloroethylene (TCE) that is occurring in the subsurface of the Evanite site in Corvallis, OR. Two anaerobic studies were conducted to investigate the effects of microbial communities in the presence of different electron donors during the anaerobic degradation of trichlorofluoroethylene (TCFE), and...
Mixtures of 1,4-dioxane (1,4-D) and chlorinated aliphatic hydrocarbons (CAHs) are common and hazardous groundwater contaminants that can be challenging to address with traditional remediation strategies. Bioremediation through aerobic cometabolism has the potential to be an effective in-situ treatment strategy for these contaminants. Rhodococcus rhodochrous strain ATCC 21198 is capable of...
Laboratory scale microcosm studies were conducted using site specific groundwater and aquifer solids to assess the feasibility of stimulating indigenous microorganisms in-situ to biologically transform Trichloroethylene (TCE) and its lesser chlorinated daughter products dichloroethylene (DCE) and vinyl chloride (VC). Three different treatments were conducted to determine the best approach for...