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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.
191

Chemical and isotopic patterns of nitrate variability in the southern Willamette Valley, Oregon /

Vick, Christopher Flanders. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 113-125). Also available on the World Wide Web.
192

Development of a one dimensional subsurface contaminant transport model with stochastic applications

Johnson, Benjamin Waldon, January 2009 (has links) (PDF)
Thesis (M.S.)--Missouri University of Science and Technology, 2009. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 10, 2009) Includes bibliographical references.
193

Implications of the geological structure of the Qoqodala Dolerite ring complex for groundwater dynamics. /

Nhleko, Olivia Lebogang. January 2008 (has links) (PDF)
Thesis (MSc.(Faculty of Natural Sciences))--University of the Western Cape, 2008. / Includes bibliographical references (leaves 80-83).
194

The significance of groundwater-surface water interactions on hyporheic physico-chemistry and stream ecology in two Scottish mountain rivers

Grant, Jane D. January 2008 (has links)
Thesis (Ph.D.)--Aberdeen University, 2008. / Title from web page (viewed on July 20. 2009). Includes bibliographical references.
195

A geographic data model for groundwater systems

Strassberg, Gil. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.
196

Measuring total toxicity and genotoxic potential of ground-waterborne Dense Non-aqueous Phase Liquids (DNAPL)

Robertson, Natasha 31 March 2010 (has links)
M. Tech. / Background: Groundwater is essential for many human activities, especially as a source of drinking water. Contaminated groundwater threatens many valuable water resources which may have adverse human health consequences. Groundwater contamination often goes unnoticed as it occurs underground and it is often impossible to, and often very expensive to rehabilitate. Groundwater pollution originating from industrial sites is a general problem in many industrialized countries, but also in developing countries such as South Africa. Among the various types of groundwater contamination, DNAPL (Dense Non-Aqueous Phase Liquids) contamination is a common one. A generic test for determining DNAPL contamination in water and their adverse effects on human health that consume this water does not exist. This study was aimed, by using two known immunoassays, to asses the toxicity and DNA damaging potential, using known techniques, of two index DNAPL and untested groundwater from newly drilled boreholes in areas suspected of DNAPL contamination. Objectives: To compile a DNAPL guideline based the use of index chemicals (Tricloroethylene [TCE] and Aroclor® 1254 [ARO]) to determine the high-end values and a series of reference (non-contaminated ground, and other treated waters) samples used to determine low-end values. PBMC were exposed to these samples and the test reactions for cytotoxicity and DNA damage measured. The methodology was then applied to groundwaters taken from an industrial site. This was to establish the health effects of these waters as well as determining whether they had DNAPL contamination.
197

Geospatial analyses of groundwater depletion and contamination: Multiscale - global, regional and local analyses

Lotfata, Aynaz 09 August 2019 (has links)
The overarching objective of this dissertation was to study groundwater resources on global, local, and regional scales. The first objective of this dissertation was to analyze the groundwater nitrate contamination in the Edwards-Trinity and the Southern High-Plains aquifers of Texas. The second was to study groundwater quality in terms of seawater intrusion in the California Coastal Basin, Upper Floridian, and North Atlantic Coastal Plain aquifers. This dissertation also provided a comprehensive overview of the groundwater level in basins at the global scale and further analyzed agricultural activities on groundwater storage in small and large basins. To achieve first objective, Ordinary Least Square (OLS) and Geographically Weighted Regression (GWR) models were used to study the relationship between groundwater nitrate contamination and land use. This dissertation further identified dominant groundwater types using USGS well data and to estimate the extent of seawater intrusion in terms of dominant ions and ocean salinity in the United States coastal aquifers. Finally, groundwater storage anomaly was quantified using Gravity Recovery and Climate Experiment (GRACE) derived variations in total Terrestrial Water Storage (TWS) and the Global Land Data Assimilation System (GLDAS). Land cover data representing a percentage of irrigated lands using groundwater resources was used to study agricultural activities on groundwater storage. Groundwater nitrate contamination was positively associated with cotton production in Southern High-Plains and Edwards-Trinity aquifers. The nitrate concentrations tended to increase as the well-depth decreased in both aquifers. Results showed that the dominant ions in the study area were Na+ and Cl- . The study concluded that Na-Cl and mixed Ca-Mg-Cl were dominant water types in the United States' coastal aquifers. Results also indicated that seawater intrusion is occurring in the US coastal aquifers. Groundwater depletion has increased in southern Asia, western North America, and southwestern Europe due to groundwater withdrawal for agricultural use. However, farming practice is not the main reason for groundwater scarcity in South America, Africa, and Australia.
198

Theoretical and field studies of fluid flow in fractured rocks

Hsieh, P. A. January 1983 (has links) (PDF)
Thesis (Ph. D. - Hydrology and Water Resources)--University of Arizona, 1983. / Includes bibliographical references (leaves 194-200).
199

Delineating contributing areas for karst springs using NEXRAD data and cross-correlation analysis

Budge, Trevor Jones, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
200

The effects of dispersion and mixing on radionuclide dating of groundwater

Bitner, Michael J. January 1983 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1983. / Includes bibliographical references (leaves 98-101).

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