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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Fe⁰-enhanced bioremediation for the treatment of perchlorate in groundwater

Jose Sanchez, Aiza Fernanda, Katz, Lynn E., Speitel, Gerald E., January 2003 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisors: Lynn E. Katz and Gerald E. Speitel Jr. Vita. Includes bibliographical references. Also available from UMI.
342

Dispute resolution to help prevent or resolve groundwater conflict in rural southwestern Ontario

Harris, Katharine. January 1998 (has links)
Thesis (M.E.S)--York University, 1998. Graduate Programme in Enironmental Studies. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL:http://wwwlib.umi.com/cr/yorku/fullcit?pMQ27352.
343

Analysis of the bioremediation of heavy metals and chlorinated solvents with emphasis on the utility of molasses injection

Smothers, Daniel Anthony. January 2002 (has links)
Thesis (M.S.)--Mississippi State University. Department of Agricultural and Biological Engineering. / Title from title screen. Includes bibliographical references.
344

Experimental evaluation of foam in environmental remediation

Rong, Jiann Gwo. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
345

Characterization of tetrachloroethene dechlorinating cultures and isolation of a novel tetrachloroethene to cis-1,2-dichloroethene halorespiring bacterium /

Pietari, Jaana M. H. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 228-244).
346

Impact of land reclamation and urbanization on groundwater flow systems /

Nandy, Subhas. January 2002 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 167-178).
347

Limiting root zone leaching to reduce groundwater contamination in sandy soils

Hall, James Olin. January 1991 (has links) (PDF)
Thesis (M.S.)--California State University, Fresno. / Includes bibliographical references. Also available in print.
348

A policy proposal for regional aquifer-scale management of groundwater in Texas

Dupnik, John Thomas 28 February 2013 (has links)
Management of groundwater as a common pool resource relies heavily on an institutional design that is fitted to the aquifers to be managed and is scaled to provide efficient and effective governance. Texas has committed to a decentralized system of groundwater management through Groundwater Conservation Districts (GCDs) that offers a high level of local control and area-specific adaptability. However, increasing pressures on the state’s groundwater resources coupled with a strong local aversion to outsider interference has resulted in a proliferation of small single-county GCDs that are neither well fitted to the aquifer systems nor sufficiently scaled to be efficient or effective. In recognition of these challenges, the persistent response has been a slow transition towards larger-scale management. Although a full transition to centralization via state control is not likely to be politically feasible, it would also be limited in its effectiveness, recognizing the wide diversity of climate conditions, water use patterns, growth projections, and aquifer characteristics that exist across the state. Regionalization is offered as a policy proposal for an institutional arrangement and scale of groundwater governance that provides a balance between centralization and decentralization, using institutions that are better fitted to the aquifer systems and appropriately scaled to provide sufficient funding and resources. The merits and logic of regionalized groundwater management have been recognized as demonstrated by the establishment of the joint regional-planning process within aquifer-based Groundwater Management Areas (GMAs), using GCD representatives as the de facto regional groundwater planners. However, the new unfunded mandates for which the already underfunded GCDs are now responsible and the extraordinary planning process complexity that has developed may prove to be unworkable. This realization compels consideration of management through regional authorities designed using the ready-made framework of the GMAs and principles gleaned from successful models of regionalization from other states and within Texas. Such regional authorities, if provided with sufficient resources and authority, would respect the logic of fit and scale and would be better equipped to address the current and future groundwater management challenges in Texas. / text
349

Analysis of the potential impacts of shale gas development

Yi, Hyukjoong 29 October 2013 (has links)
The objective of this thesis is to analyze the considerations regarding the environmental impacts of shale gas development by a rational, objective, fact-based assessment. Flowback and produced water from shale gas development can be treated with the related technologies on-site or off-site for recycling, reuse, discharge, and disposal. However, more efficient technologies should be researched even though current levels are high. Besides, the amount of water used in shale gas development is generally lower than that of other energy sources and most shale gas plays are located in areas with moderate to high levels of annual precipitation. However, growing populations, other industrial water demands, and seasonal variation in precipitation should be considered during shale gas development. Groundwater contamination is directly connected to the integrity of the well casing, not hydraulic fracturing, because there are significant spacious gap and several impermeable layers between target formations and ground water zones. Hydraulic fracturing rarely creates unwanted induced seismicity because the seismic energy created from hydraulic fracturing is too low to be detected in the surface, compared to the waste injection well. / text
350

Controls on saline intrusion into the Crag aquifer of north-east Norfolk

Holman, I. P. January 1994 (has links)
The River Thurne catchment on the north-cast coast of Norfolk contains large areas of marshland, including several Ramsar-designated sites. Land drainage of much of the marshland over the previous centuries has lowered groundwater levels to below sea-level. Consequently, saline groundwater has intruded into a large proportion of the underlying Norwich Crag aquifer, thereby raising the salinity of the surface water networks. Changes in the economics of arable farming and the perception that changes in the land drainage regimes will produce beneficial effects on the water quality of the River Thume and its associated Broads have necessitated the need for a better understanding of the hydrogeology of this complex, highly managed aquifer. To provide the necessary understanding, this study has investigated the hydrogeology, hydrology and land management of the catchment using a variety of geophysical techniques, including electrical resistivity soundings EM surveys and reflection seismology to supplement information collected using standard hydrogeological measurements The distribution of dyke water levels as maintained by the drainage pumps are shown to exert important controls on the extent and depth of saline intrusion. In the north of the catchment a further control is the internal structure of the Crag aquifer. A clay layer of probable Baventian age divides the Crag aquifer into two units and appear to prevent the salinization of the aquifer above this layer. A catchment water balance has shown that land drainage pumps discharge about 95% of the catchment recharge, so that raising dyke water levels will also result in raised groundwater levels. Futurel and use change to grazing marsh, while improving the water quality of drainage water entering the River Thurne may lead to increased salinization of the aquifer, as a result of changes in the distribution of dyke water levels.

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