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Origin Of High Levels Of Ammonium In Groundwater, Ottawa County, Michigan, Derrick Lingle

Masters Theses

Groundwater from wells located in and around Hemlock Crossing Park in Ottawa County, Michigan has elevated levels of ammonium. High ammonium concentrations in potable water wells are a common indicator of anthropogenic impact, such as landfill leachate or agricultural activity. Ammonium can also occur in groundwater through the decay of natural organic material. Along with the retrieval of a complete glacial sediment core via rotasonic drilling, numerous chemical and isotopic parameters were used to determine the source of ammonium in the impacted aquifer.

Buried organic material, deposited during the Athens subepisode interglacial period, is in contact with groundwater containing elevated …

Activated Carbon Preconditioning To Reduce Contaminant Leaching In Cement-Based Stabilization Of Soils, Renee Elizabeth Crane

Masters Theses

Powdered activated carbon (PAC) is often added with cement to enhance the stabilization and solidification (S/S) of materials contaminated with organic compounds. Adsorption of organic contaminants onto PAC can reduce leaching of organic contaminants. Simultaneous addition of PAC and cement reduces soil handling costs, but cement hydration reactions coat PAC with Ca(OH)2 before contaminants can be adsorbed onto PAC. Laboratory studies were done on four aged, contaminated soils from manufactured gas plant sites to compare the performance of S/S treatment with simultaneous addition of PAC and cement vs. cement addition after preconditioning with PAC to enhance contaminant adsorption. Performance was …

Using Soil Organic Matter As An Iron Chelate To Enhance The Efficiency Of Modified Fenton Oxidition Of Diesel Fuel In Arctic Soils, Mary K. Sherwood

Masters Theses

Laboratory experiments were conducted to investigate the use of modified fenton chemistry on the treatment of three soils from the Canadian arctic, all with abundant soil organic matter, iron and manganese oxides, and diesel fuel contamination. The purpose of these studies was to (I) to assess modified fenton chemistry as a treatment option for petroleum-contaminated arctic soils, and (2) to evaluate the impact of soil organic matter on the modified fenton treatment of soils. Modified fenton treatment was compared for reactions in which ethylenediaminetetraacetate was added as a chelate vs. reactions in which the native soil organic matter was the …

Surface Complexation Modeling Of Cr(Vi) Absorption On Mineral Assemblages, Ann M. Gilchrist

Masters Theses

Hexavalent chromium (Cr(VI)) is a waste product of many anthropogenic processes. Because it is highly mobile, the improper disposal of Cr(VI) has caused widespread contamination. Because reduction and adsorption reactions may reduce the bioavailability and mobility of Cr(VI) in environmental systems, a better understanding of Cr(VI) adsorption behavior will improve remediation efforts.

Subsurfaces and soils are heterogeneous, however most studies focus on single sorbate/sorbent interactions to develop surface complexation models (SCM) for prediction of heavy metal adsorption. Theoretically, combining the SCMsdeveloped for single sorbate/sorbent systems should yield accurate predictions of adsorption in more complex systems (i.e., the component additivity approach …

Development And Evaluation Of An Inquiry-Based Unit For Teaching About Paleoclimate And Climate Change, Steven Barone

Masters Theses

The purpose of this action research study is to develop and evaluate a sequence of four lessons for an introductory earth science course taken by future elementary teachers. Action research is a reflective process of data collection and analysis used by teachers to improve their classroom practice. This study’s goal is to produce a series of lessons that align with the course philosophy of student-driven learning through guided-inquiry and are effective at improving students’ understanding of climate change.

Three data sets were used to evaluate the lessons: 1) student knowledge gains on an objective pre- and post-test, 2) students’ self-reported …

Creating Sustainable Economic And Ecological Growth In The Congo Basin: Bushmeat Consumption And Biodiversity Protection, Richelle Lynn Warnock

Masters Theses

This research examines the economic and ecological sustainability of bushmeat hunting in the Congo Basin, specifically the Democratic Republic of Congo and the Republic of Congo. Although bushmeat hunting has provided short term gain for individuals in the region, long term solutions focusing on micro and macro level interventions may provide community wide benefits, while protecting Congo Basin wildlife. Research shows that a focus on the development of key economic sectors such as agriculture, mineral resources and hydroelectricity, as well as the growth of infrastructure may provide viable economic gain for the Congo Basin. Ecotourism and improvements to forest management …