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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.
31

Design of wellfield and recharge operations in forebay area of San Bernardino basin, California

Maxfield, Sandra Leigh, 1956- January 1990 (has links)
East Valley Water District is located in San Bernardino, California which is approximately 50 miles east of Los Angeles. In order to meet future water demands, East Valley Water District plans to increase recharge activities in the forebay area of the San Bernardino groundwater basin and expand wellfield operations immediately downgradient. Three possible recharge and wellfield designs were under consideration with annual recharge rates increasing 10,000 to 20,000 acre-feet/year in the Santa Ana spreading basins. Approximately four to five new production wells pumping an equal quantity of groundwater have been proposed. A two-dimensional finite element groundwater flow model was constructed and calibrated to reproduce historical water level data for the year 1945. They calibrated model was applied to simulate the hydrologic effects of each of the three designs over a ten-year period.
32

The regional effect of water table lowering in the Durban area

09 September 2010 (has links)
No abstract available. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 1973.
33

Recognizing groundwater as a site development limitation factor

Davis, James Rodrick January 1984 (has links)
This study observes how the size and type of land development can often be limited by the supply of fresh groundwater sources. Multiple-use recharge basins were found to be effective in diverting pollutants around a potable source of groundwater, thus reducing the chances of that source becoming contaminated. A computer-aided numerical model was used to simulate groundwater flow and its responses to recharge basins in a hypothetical situation.Through a series of trials, artifical recharge was able to abate the problem of groundwater contamination in certain geohydrologic conditions. Optimum rates of recharge and discharge were determined to effectively divert contaminated groundwater around several types of developments. From these findings, land use options and development intensities can be safely recommended for areas which otherwise may have been nearly undevelopable. / Department of Landscape Architecture
34

A Study of the Precursors for Disinfection By-Products on the CAP Avra Valley Recharge Project

Lutz, Theresa Marie January 2000 (has links) (PDF)
Thesis (M.S. - Soil, Water and Environmental Sciences)--University of Arizona. / Includes bibliographical references (leaves 107-111)
35

Spatial and temporal biogeochemical changes of groundwater associated with managed aquifer recharge in two different geographical areas /

Reed, Deborah A. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2008.
36

Urban stormwater injection via dry wells in Tucson, Arizona, and its effect on ground-water quality

Olson, Kevin Laverne, 1954-, Olson, Kevin Laverne, 1954- January 1987 (has links)
My deepest respect and appreciation are extended to Dr. L. Gray Wilson for providing the opportunity to conduct this research, for his advice and assistance during the course of the research, and for his review of and suggestions for improving this manuscript. I would also like to thank Michael Osborn for his assistance. This research was funded by the City of Tucson. The assistance and direction provided by Mt. Bruce Johnson and Mt. Joe Babcock at Tucson Water are gratefully acknowledged. My thanks are also extended to Dr. Daniel D. Evans, Dr. L.G. Wilson, and Dr. Stanley N. Davis for serving on my thesis committee. Bruce Smith's assistance is gratefully acknowledged. Bruce spent two long days with 110-degree temperatures In a parking lot describing the lithology of sediment samples collected during the drilling phase of this research. He also determined the moisture content and particle size distribution on samples collected from the borehole. The assistance of Ralph Marra and Steve Brooks is also gratefully acknowledged. Ralph waded through city and county bureaucracies to determine zoning at each dry-well site. Steve assisted with collecting dry-well settling chamber sediment samples.
37

Collection and analyses of physical data for deep injection wells in Florida

Unknown Date (has links)
Deep injection wells (DIW) in Florida are regulated by the U.S. Environmental Protection Agency (USEPA) and the state of Florida through the Underground Injection Control regulations contained within the Safe Drinking Water Act. Underground injection is defined as the injection of hazardous waste, nonhazardous waste, or municipal waste below the lowermost formation containing an underground source of drinking water within one-quarter mile of the wellbore. Municipalities in Florida have been using underground injection as an alternative to surface disposal of treated domestic wastewater for nearly 40 years. The research involved collecting data as of September, 2007 on all the Class I DIWs in the state of Florida and evaluating the differences between them. The analysis found regional differences in deep well practice and canonical correlation analyses concluded that depth below the USDW is the most significant factor to prevent upward migration of the injected fluid. / by Jie Gao. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
38

Apparent fate of recharged nonpurgeable chlorinated organics

Weissenborn, Richard Carl, 1952- January 1988 (has links)
Secondary effluent from the Roger Road Wastewater Treatment Plant undergoes tertiary treatment of dual media filtration and chlorination. The tertiary effluent is recharged and subsequently extracted for irrigation in Tucson, Arizona. The fate of chlorinated organics in this recharge system was investigated in this research. Nonpurgeable organic carbon was found to reach a constant level in the groundwater after being recharged. Not all of the organic carbon was removed from the water. Nonpurgeable organic halogens increased as they flowed away from the recharge basins. Reasons for this increase were not determined. Attempts were made to define the apparent molecular weight distribution of the NPOC and the NPOX. Measured values of the two parameters were consistently greater after the analytical processing than before, making the determination impossible.
39

Water reclamation in Thurston County a review of LOTT's planned class A water expansion /

Smith, Kathryn Ann. January 1900 (has links) (PDF)
Thesis (M.E.S.)--Evergreen State College, 2009. / Title from title screen (viewed 4/15/2010). Includes bibliographical references (leaves 63-67).
40

The feasibility of artificial recharge of the Bushmans River Mouth Aquifer

Nickall, Enéz Sarah-Leigh January 2008 (has links)
The main aim of the project is to investigate the feasibility of artificial recharge of the Bushmans River Mouth Aquifer in the Eastern Cape. The suggested method of recharge is through natural infiltration through a series of wetlands in the back dune area. The proposed site was the Klipfontein Vlei which is located just north of the Bushmans River Mouth. Artificial recharge is defined as augmenting the natural movement of surface water into underground formations by some method of construction, the spreading of water, or by artificially changing natural conditions. A variety of methods have been developed, including water spreading, recharging through pits and wells, and pumping to induce recharge from surface water bodies. The choice of a specific method is controlled by local topography, geology and soil conditions, and the quantity of water to be recharged and ultimate water usage. In special circumstances, land value, water quality, and climate play an important role. Artificial recharge is not a foreign concept to South Africa and this project is to test its feasibility in a back dune wetland area. Augering done in the study area revealed the dominance of sandy loam in the upper layers of the pans, loamy sand in the middle levels and the presence of some sand lenses in the lower reaches. Particle size analysis done by sieving and hydrometer test, showed a dominant 3f fraction. There was variation in modes in pan 1 from unimodal to bimodal to trimodal. Pan 2 showed no variation as all samples were unimodal and moderately well sorted. Infiltration tests were done by a double ring infiltrometer. These results showed that the infiltration rates of the pans became stable after 15 to 20 minutes, thus indicating that the soil had reached its saturation point. The resistivity surveys revealed a stepped water table. The inclination of the water is controlled by the predominately argillaceous horizons of the Bokkeveld Group. Based on the above results, it is recommended that the Klipfontein Vlei be used as an artificial recharge site.

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