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Addressing Mercury Contamination From Artisanal Gold Mining In Colombia: Pollution Exposure, Health Risk, And Educational Efforts In The Communities Of La Toma, Colombia, Kelli Mccourt

All Dissertations

Artisanal and small-scale gold mining (ASGM) has become a primary environmental and public health concern in the region of Colombia known as Alto Cauca. The predominantly Afro-descendent communities of Yolombó and La Toma in Alto Cauca have experienced pollution linked to the use of mercury in the ASGM process. For the past decade, mercury has emerged as a contaminant of increasing concern in the communities due to its toxicity and ability to bioaccumulate and biomagnify. Likewise, mining in the region raises concerns over the leaching of metals into local waters. Given the complexity of risk and pollution in the communities, …

Impacts Of Forest Management On Carbon And Mercury Export In Eastern And Western United States Forests, Hunter James Robinson

All Theses

Forest management practices including prescribed burning and mechanical thinning are used to maintain the best health of a forest for the intended management goal. These management practices disturb natural biogeochemical cycles including carbon and mercury. Forest floor detritus materials and woody fuels serve as the main source of carbon and mercury that naturally grows and shrinks during normal decomposition cycles. Management manipulates the forest floor through material removal as a result of prescribed burning or an addition of materials due to mechanical thinning. Compounded with post management hydrologic factors there is potential for localized and downstream impacts. Management practices are …

Feasibility Study Of Thermal Treatment For Mercury Removal From Soils, Thomas Edward Spain

All Theses

Thermal remediation is an established method for the remediation of volatile organic compounds (VOCs). Thermal remediation for the remediation of elemental mercury was successfully applied by Kunkel et al., 2006 in the laboratory scale. Before the technology can be applied to the field scale, the thermal treatment for mercury needs to better understood using numerical simulation.

The Department of Energy’s TOUGH2/TMVOC Code was developed at the Lawrence Berkeley National Laboratory and was used to evaluate the potential effectiveness of thermal treatment to remediate elemental mercury. TMVOC is a three phase non-isothermal numerical simulator for water, gas, and VOCs in porous …

Using Nestling Bald Eagles To Assess Spatial And Temporal Trends Of Environmental Contaminants, Voyageurs National Park, Minnesota, Henry Pittman

All Theses

Bald eagles (Haliaeetus leucocephalus) are a avian species used to monitor environmental contaminants such as mercury (Hg), methylmercury (MeHg), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCs) in North America. Populations of bald eagles nesting along the Great Lakes were very slow to recover after the ban of PCBs and OCs because these compounds were very persistent. Bald eagles at Voyageurs National Park (VNP) have been monitored since 1973 and provide an opportunity to assess temporal and spatial trends of persistent environmental contaminants. Nestling bald eagle feathers were analyzed for Hg concentrations for the past 12 years. Nestling bald …

An Approach Designed For Reginal Prospective Human Health And Ecological Risk Assessment And Its Application To Mercury Risks From A Coal-Fired Power Plant, Pathratipa Sansayavichai

All Dissertations

A large and/or long-term released source of a toxic chemical(s) can cause adverse effects to humans and non–human species inhabiting all over the region. The overall goal of this dissertation was to improve practices in risk assessment concerning a regional risk posed by a prospective source. A generic conceptual framework for performing regional prospective human health and ecological risk assessment was developed. The formulation of a priori considerations was used to identify the possible sources of uncertainties in the prospective risk assessment. Physiologically based pharmacokinetic (PBPK) modeling was utilized to reduce uncertainty in a toxicologically safe dose used in risk …

Analysis Of Mercury And Lead In Birds Of Prey From Gold-Mining Areas Of The Peruvian Amazon, Peggy Shrum

All Theses

This study was conducted to determine levels of lead and mercury in the raptors of the South-eastern Peruvian Amazon. The study took place within the Los Amigos Conservation Concession in Madre de Dios, Peru. Eighty-six raptors from among sixteen species were captured with Bal-Chatri traps. From each individual, feather samples were obtained for mercury analysis and blood was taken for lead analysis. Each raptor was then released without incident or injury.
Mercury amalgamation for gold extraction is widely used by small-scale, transient mining operations, which are numerous along the rivers and creeks in the tropical forests and other locations in …

Constructed Wetland Treatment System: An Approach For Mitigating Risks Of Flue Gas Desulfurization Waters, Derek Eggert

All Dissertations

Federal laws regarding ambient air quality are currently requiring industries to reduce emissions of sulfur dioxides (SO2). Coal-fired power plants have therefore begun implementing flue gas desulfurization (FGD) scrubbers that utilize a highly oxygenated water stream (calcium carbonate saturated water) to transform sulfur gases into soluble anion species (e.g. sulfite and sulfate). This FGD process also transfers potentially toxic constituents including arsenic, cadmium, chemical oxygen demand, copper, mercury, selenium, chloride, sulfates, and zinc into the scrubbing water. These scrubber waters, referred to as FGD waters, present an industrial problem due to the large volumes produced (378,000 to 1,900,000 L/day) and …

Influence Of Mercury-Dissolved Organic Matter (Dom) Complexation On Toxicity In Natural Waters, Christina Mcnaughton

All Dissertations

Global industrialization, coupled with a large biogeochemical cycle that moves mercury through the environment, has resulted in higher mercury concentrations being detected in many environmental compartments. Although the presence of mercury in each compartment has the potential to elicit toxicity, mercury found in natural waters provides the greatest risk, due to the various reactions it can undergo, resulting in a plethora of different species.
Due to the fact that mercury contamination in aquatic systems has the potential to bioaccumulate and biomagnify up the food chain and cause toxicity, understanding the behavior of mercury in these systems is imperative in the …