<p> The search for clean, fresh water is of the utmost importance, especially considering the highly industrialized age in which we live and the rising demand caused by increasing population. Many once-clean groundwater reservoirs have been tainted due to the inadequate storage and handling procedures for hazardous materials. One such site operated as a wood-preservation facility between 1937 and 1999 located in western Louisiana in the town of DeRidder. The contaminants that leached into the soils and groundwater supply at this site included creosote, a coal-tar distillate that is an amalgamate of several toxic constituents. The contamination was first detected in 1981, and within the year monitoring wells were installed to evaluate the extent of the pollution. For this study, 61 monitoring wells, 16 of which consistently record hazardous compounds within the subsurface, were analyzed in order to evaluate the temporal and spatial changes of contamination. The data were further correlated with rising and falling groundwater levels, precipitation data, and lithology in order to better understand the trends of the constituents and how they are affected by their environment. Additionally, an indication as to the efficiency of the current remediation practices put in place is examined by evaluating the diminishing contamination values over time compared to previous studies in the area. Hazardous levels within the soil are at their peak near the contamination sources, and spread outward while following the direction of local groundwater flow. This study shows that the total contamination quantities are slowly declining due to the current remediation practices, however, the total area covered by contamination fluctuates over time, and is currently in a state of expansion towards the southwest. A correlation between rainfall events and contamination spikes was noted in a previous study of the area, however, no such correlation was observed in the more recent data.</p>

<p> This project explored the potential fate and transport of seawater-based drilling fluid used in the Antarctic Drilling Program (ANDRILL) South McMurdo Sound project (SMS). The SMS drilling reported a loss of 5.6 &times; 10⁵ liters of drilling fluid to the surrounding formation throughout a borehole depth of 1139m. The introduction of these drilling fluids raise concerns of potential contamination to a pristine, isolated environment. The volume of fluid lost to the subsurface is unrecoverable and will only break down through natural attenuation processes, such as biodegradation. The objectives of this study are to estimate the extent of fluid migration laterally from the borehole and to determine when biodegradation of the water-based drilling fluid is effectively occurring. Variable density groundwater flow modeling (SEAWAT) was used to simulate the environment around the borehole. Applying stresses similar to the drilling events produced an estimate of how far fluid will be transported as drilling fluid is being circulated. Results show the fluid to migrate up to 7.5m into the subsurface. Additionally, laboratory microcosms were set up to incubate drilling fluid samples at various temperatures (5, 25, and 50&deg;C) under aerobic and anaerobic conditions. Experimental data collected over 188 days was analyzed to evaluate the time frame when biodegradation of drilling fluids occurred. Carbon isotope fractionation (¹³C/¹²C) was used to determine the ability of the drilling fluids to be used as a food source. Biological data observed changes in microbial growth using DNA quantification, and changes in microbial communities using Biolog EcoPlates&trade;. Results show a positive correlation between the increase of &delta;¹³C (&permil;) values and an increase in DNA (ng/&micro;l) quantity. Data from geochemical and community changes indicate biodegradation of the drilling fluid occurred between time 40 and time 100. The methods employed to investigate fate and transport is a unique approach, and applied to these water-based drilling fluids for the first time in this study.</p>

<p> The act of thru-hiking a long-distance trail immerses hikers in the natural world for an extended time; as such, it represents a compelling system to study the relationships between a specific appreciative activity&mdash;thru-hiking&mdash;and environmental attitudes regarding sustainability. This thesis critically explored the primary research question: How do thru-hikes change or inspire environmental attitudes in thru-hikers on long-distance trails in the United States? I employed the revised NEP scale to survey 98 thru-hikers using snowball sampling and I interviewed a subset to gain more in-depth knowledge. In addition, I textually analyzed the blogs written by thru-hikers. Findings suggest that environmental attitudes of thru-hikers already leaned in an ecocentric direction before thru-hiking and after thru-hiking, their environmental attitudes became more so. Furthermore, this thesis finds that women had more ecocentric views than men before and after thru-hiking and that more ecocentric attitude change occurred for thru-hikers in their twenties than other age groups. Thru-hikers also chose to express their environmental views through conversations and their actions. And thus, thru-hikes on long-distance trails in the United States have the potential to strengthen and/or reinforce existing ecocentric attitudes in thru-hikers.</p>

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

No description available.

Mountain lakes are an iconic feature of the landscape in the Mountain West. They hold significant ecological and cultural value, and are important sentinels of environmental change. Despite their pristine image, these remote waterbodies are subjected to numerous anthropogenic stressors. Mountain lakes are naturally fishless systems, but historical fish stocking has led to major changes in mountain lake food web structure, including declines of resident amphibians, large-bodied zooplankton, and emergent insect populations. Atmospherically deposited contaminants, such as mercury, can accumulate in mountain lake food webs, leading to relatively high levels in the fish relative to the water. Managing for these stressors is difficult, because although fish stocking causes ecological problems, and mercury bioaccumulation poses human health risks, the cultural value of angling remains important. The goal of this dissertation was to better understand the issues of fish stocking and mercury bioaccumulation in a socioecological context: from the importance of trophic dynamics for mercury bioaccumulation in mountain lake fish, to the implications fish stocking and mercury bioaccumulation for mountain lake management. In Chapter 2, I identified the ecological, limnological, and landscape-level indicators of mercury bioaccumulation in mountain lake food webs in order to inform better ecosystem management. In Chapter 3, I conducted an experiment to test if fatty acid stable isotopes can partition benthic and terrestrial prey sources in fish in a simplified mountain lake food web, in hopes of providing a more informative tool for future food web studies. In Chapter 4, I used intercept surveys to determine the public perceptions of mountain lake fisheries management in two national parks, and assess the risk mercury may pose to mountain lake anglers by determining fish consumption habits. I determined that nearshore forest cover and fish diet were the best predictors of mercury concentrations in mountain lake fish, but that our understanding of the role of terrestrial prey subsidies for fish is constrained by limitations in current diet tracing methods. My experiment demonstrates that using stable isotopes of fatty acids is a promising approach to distinguishing between benthic and terrestrial diet sources, but that doing so effectively requires an in-depth understanding of physiological context specific to the ecosystem of interest. Lastly, through my surveys, I found that thousands of anglers regularly consume fish from mountain lakes, and that while most visitors have concerns about the ecological impacts of fish stocking, anglers support a conservation-based approach that balances ecological health with the cultural value of fish stocking. This dissertation provides a unique set of tools that advance our understanding of food web dynamics and mercury bioaccumulation in mountain lakes, as well as the social value of these ecosystems. My results suggest that the most effective way to protect the health of mountain lakes and their visitors will be for managing agencies to collaborate with scientists and angling groups when making fisheries management decisions, and to invest in outreach about both the ecological and toxicological implications of fish stocking and mercury bioaccumulation in mountain lakes. The use of such socioecological research approaches is becoming progressively more important, as the threats of climate change and unstable regulatory protections for mountain ecosystems increase.

Hundreds of thousands of organizations have chosen to boost their competitive position by demonstrating compliance to the ISO 14001 Environmental Management System standard. In order for these standards to become credible policy options, they must ensure the capacity to build an industrial morality and to institutionalize responsibility. Relying on a series of in-depth interviews with environmental auditors, this dissertation contributes to a deeper empirical understanding of these regulatory instruments by, first, exploring how the adoption of an EMS promotes self-regulatory capacity and contributes toward effective environmental protection, and second, discussing the limitations of its accountability structure and the threats to the credibility of the standard. / This project highlights several misconceptions associated with the role of ISO 14001, and explains why both public and private sectors hold conflicting and inappropriate expectations regarding the certification process. According to the environmental auditors interviewed, the standard has helped thousands of committed organizations to effectively improve their self-regulatory capacity as well as their environmental performance. Yet, organizations with no intrinsic motivation can take advantage of the flexibility granted by the standard and the limitations of the conformity assessment process, to obtain an empty environmental certificate. ISO 14001 is a process standard that can help both 'environmental leaders and laggards', but that cannot differentiate organizations based on their level of environmental performance. Because of that, ISO 14001 is increasingly perceived as a socially unacceptable certification system. This project concludes that ISO 14001 is a double edge regulatory instrument that aims both to foster self-regulatory powers, and to act as a market signaling agent. The problem lies in the fact that these two facets of the standard are actually detrimental to each other, perpetuating a cycle that contributes to the discredit of the standard and of the auditing community. In the future, ISO 14001 needs to adjust its non-prescriptive nature and its accountability mechanism, to the character of the organizations seeking certification. In alternative, a new generation of certification programs is emerging, building upon the ISO 14001 standard with an extra layer of requirements, and with a more meaningful role for the environmental auditor.

Thesis (doctoral)--University of London, 1997. / BLDSC reference no.: DX210064.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

Thesis (Ph. D.)--Utrecht University, 2002. / Title from title screen (viewed Mar. 22, 2004). Includes bibliographical references.