Nonylphenol is a widely used organic compound which has been reported to have potential risk to aquatic environment. According to the result of recent studies, it has been detected in many lakes in Stockholm, Sweden, which raised great concern. In this thesis, a dynamic fate model was adopted and modified from literature in order to study the distribution and concentration of nonylphenol in small lakes, guide the field sampling and provide information for corresponding decision making. Two lakes in Stockholm, Lake Trekanten and Lake Drevviken, were selected as case studies. Another model was included for comparison purpose. Based on the model result, the most important nonylphenol removal process in both lakes was the transformation in water. A sensitivity analysis showed that the model results were most sensitive to the process of nonylphenol water inflow. In terms of sediment concentration of nonylphenol, satisfactory agreements were obtained from the comparison between model results and field data. However, problems, such as the simultaneous handling of nonylphenol and nonylphenol ethoxylates, may cause uncertainties on the model performance. The result of the analysis about scenario load change and the seasonal variation showed that the sediment nonylphenol content is more stable to the seasonal change compare to nonylphenol water content, but the response times to load change of nonylphenol content in these two compartments are quite close and somewhat lower than the water residence time.

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Karst waters serve as important water sources in rural Appalachia and are well-connected to surface waters, making them susceptible to anthropogenic contamination, including by fecal indicator bacteria which represent a public health risk. This work designed and implemented a watershed-scale monitoring program for a 26 km2 sinking stream system in southwest Virginia to determine the fate and transport of E. coli in the system. This hydrologically complex watershed is predominantly agricultural and includes multiple key surface water sinks that enter Smokehole Cave and emerge at Smokehole Spring. Field campaigns at surface sites and within Smokehole Cave included bacteriological sampling, hydrologic measurement, and dye tracing. Field data was synthesized to: 1) examine variations in E. coli concentrations in the watershed during varying flows/seasonal conditions; and 2) calculate E. coli growth/decay coefficients for the karst system during different flow/antecedent conditions. E. coli concentrations at Smokehole Spring consistently peaked days after peak hydrologic stage. Flow conditions and storm event response were the largest drivers of E. coli transport through the system. Dye trace results revealed that water from sinks can be stored or move slowly through the karst system, resurging during storm events. E. coli was calculated to decay within the karst system, with a half-life of about 5-120 days which is longer than the travel time of water through the cave of approximately 0.5-2 days. Findings indicate that E. coli transport in Appalachian karst systems is hydrologically driven, roadside spring water collection is not recommended, and bacterial treatment is encouraged if performed. Targeted land-management practices should be explored to decrease E. coli loadings in karst waters. / Master of Science / Karst (cave) waters serve as important water sources in rural Appalachia and are well-connected to surface waters, making them susceptible to contamination from human or animal waste – a public health risk. A field monitoring program was conducted in an agriculturally impacted stream and cave system in southwest Virginia to determine how E. coli, a bacteria found in the waste of humans and other animals, moves through the system. There are several places where surface water sinks into the cave system, eventually entering Smokehole Cave and emerging at Smokehole Spring. Field data collection was performed at surface sites and within Smokehole Cave including sampling for E. coli, water flow measurements, and dye tracing. Field data was combined to 1) examine variations in E. coli concentrations during varying flows/seasonal conditions and 2) calculate E. coli growth/decay coefficients for the cave system during different flow and soil moisture conditions. It was found that E. coli concentrations at Smokehole Spring consistently peaked days after the water depth. Flow conditions and storm events were the largest drivers in E. coli movement through the system. Dye trace results revealed that water from sinks can be stored or moves slowly through the cave system and resurges during storm events. E. coli was found to decay within the cave system. Findings indicate that E. coli movement in Appalachian cave systems is driven by storm events, roadside spring water collection is not recommended, and bacteria treatment is recommended if performed. Cave-specific land-management practices are recommended to keep E. coli from entering cave waters.

The Contaminant Model for Streams (CMS) was developed for use in studies where both data and resources for model application are limited. CMS can be quickly and easily applied, yet it is still versatile enough to be used for a variety of conditions ranging from short term spill modeling to multi-year simulations of contaminant fate in stream water and bottom sediments. The model can be applied for both organic and inorganic contaminants. Suspended solids can be transported or a steady-state concentration may be input. Steady-state, uniform hydraulic conditions are assumed within the modeled reach, which greatly reduces model complexity. A model application may consist of one or more reaches connected in series or in a branched network. Possible sediment model configurations include: 1) water column only, 2) water column and mixed sediment layer, and 3) water column, mixed sediment layer, and deep sediment layer.

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The aim of this dissertation is to examine and helpfully elucidate Kant’s proleptic philosophy of history by pursuing lines of thought across both his critical and historical body of work. A key motivation for this goal stems from noticing certain repetitive explications of Kant’s philosophy across, among other subjects, history, biology, religion, teleology, culture, and education, which, as precise and careful in their detail, all seem to converge on key Kantian ideas of teleology and morality. Rather than concentrating on any one aspect of Kant’s proleptic philosophy, I set out to (i) investigate seemingly untenable problems with his characterization of reason in history, (ii) to counter what I take as a misreading, if not misattributions, of Kant’s proleptic, and not prophetic, thoughts on historical progress, (iii) to offer an original reflection on Kant’s use of a famous stoic phrase in two of his political essays, and (iv) to an attempt a close exegesis toward tying notions of teleology and hope with that of need. The approach that I take in these chapters is both problem centered and exegetical, and while I attempt to answer concerns in the secondary literature pertaining to Kant’s proleptic philosophy of history, I also stay close to the primary texts by providing references and citations to key claims and passages which reinforce Kant’s forceful portrait of the poietic power of human reason to create a world hospitable to its rational ends. / Philosophy