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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.
81

Designing a constructed wetland to treat landfill leachate

Scott, Jennifer (Jennifer E.), University of Western Sydney, Hawkesbury, Faculty of Science and Technology January 1995 (has links)
The aim of this project was to identify a suitable solution to the problem of landfill leachate at the North Katoomba landfill site. Options were affected by a range of constraints including economics, location and the intrusion of ground water into the landfill. The initial goal was to contain and treat the leachate on site, with the eventual target to discharge into the nearest receiving waters. A constructed wetland option was devised and researched, involving identification of the major pollutants contained within the leachate, developing a concept design and estimating the likely removal efficiencies expected. Investigations identified the primary pollution parameters as microbial and nutrients. Metals were found to be low in concentration although the wetland has the capacity to deal with these pollutants should they become part of the pollution plume. A bench scale constructed wetland system was developed to give an indication of the removal efficiencies. The results suggest that a constructed wetland system would be appropriate for treating landfill leachate at the North Katoomba site. It is recommended that a constructed wetland be established in the field to determine the long term treatment prospects and the potential management problems in a practical application. / Master of Science (Hons)
82

Developing compound-specific stable isotope tools for monitoring landfill leachate

Benbow, Timothy J, n/a January 2008 (has links)
This thesis has developed a suite of compound specific stable isotope tools to monitor landfill leachate and identify the infiltration of leachate to ground water and surface water. These tools have the power to indicate the fractional contribution multiple discrete sources of pollution are making to a single location. This journey began by developing two solid phase extraction (SPE) methods to extract non-polar and polar organic compounds from leachate with minimal fractionation of hydrogen or carbon isotopes. Non-polar compounds were successfully extracted using ENV+ SPE cartridges and polar compounds were successfully extracted using Strata-X SPE cartridges. The isotopic fractionation of non-polar compounds during ENV+ extraction varied significantly (up to 245⁰/₀₀ and 1.8⁰/₀₀ for D and ��C respectively, when eluted with acetonitrile and ethyl acetate, as recommended by manufacturers) but the fractionation of compounds eluted with dichloromethane was negligible (less than instrumental precision). Polar compounds were eluted from Strata-X cartridges with negligible isotopic fractionation using methanol. The direct comparison of SPE and liquid-liquid extraction found SPE to extract slightly more compound from leachate then liquid-liquid extraction (especially for polar compounds) and the isotopic compositions of compounds did not change with extraction methods. These new analytical methods subsequently were used to determine the isotopic compositions of organic compounds dissolved in leachates from three New Zealand landfills. The molecular and isotopic signature of leachate varied significantly between landfills, indicating the isotopic fingerprint of organic compounds in leachate is unsuitable as a universal tracer of leachate. However, compounds such as terpien-4-ol, methylethylbenzene and juvabione maintained their isotopic composition over short geographical distance-indicating their potential as site-specific tracers of leachate. Organic compounds analysed on a transect across the landfill boundary indicated polar compounds were more mobile than semi-volatile compounds and possessed a more conservative isotopic composition. However, hexadecanoic acid extracted from leachate and ground water was highly depleted in ��C (-72 ⁰/₀₀ to -40⁰/₀₀), indicative of methanogenic and sulfate reducing bacteria. These bacteria only live in highly reducing environments such as leachate; therefore their presence in the pristine environment can potentially indicate the release of leachate from the landfill. The final experiments traced the uptake and utilisation of leachate by periphyton. The isotopic composition of bulk periphyton, fatty acids and phytol indicated that microbial assimilation and utilisation of nutrients is a complex process. Fatty acid biomarkers for green algae and diatoms showed signs of leachate derived nutrients, however the availability of nutrients (carbon, nitrogen, water and light) caused significant changes in metabolic processes and isotopic compositions. Under slow growing conditions, the [delta]��C composition of periphyton became enriched in ��C as solar irradiation levels decreased (including shading by detritus and periphyton), while the [delta]D composition of fatty acid was controlled by the internal recycling of hydrogen. This study indicated the power of compound specific isotope analysis as a tool to detect the release of landfill leachate from a landfill, especially at locations with multiple potential sources of contaminants, and provides a sound platform for future research.
83

Bacterial pathogens associated with sanitary landfill operations

Hayes, Gregory V. 03 June 2011 (has links)
A study of soil and water samples obtained from Ford's Sanitary Landfill and a control area north of the landfill were investigated for the presence of bacterial pathogens on November 24, 1972, and March 8, 1973. This study revealed the presence of several bacterial pathogens of animal, plant, and human significance in the landfill area. The control area investigated exhibited only normal soil microflora of nonpathogenic significance.Ball State UniversityMuncie, IN 47306
84

A study of the revegetative capabilities of selected grasses grown on sanitary landfills

Morgan, William Lee 03 June 2011 (has links)
Much emphasis has been placed on the design, operation, and construction of sanitary landfills while the proper reclamation and revegetatiun of completed. sites has often been overlooked.. Revegetation of exposed. landfill surfaces drastically reduces soil erosion, minimizes water infiltration into refuse, helps to control leachate production, and improves site appearance, thus promoting greater public acceptance of sanitary landfills.This research was designed to determine which of selected grasses used. for erosion control were best adapted to the sanitary landfill environment. The experiment was conducted on three sanitary landfills in central Indiana.Results showed that the availability of sufficient plant nutrients was critical for establishing vegetative growth. Significant variations in the performance of the individual grass species was observed.Ball State UniversityMuncie, IN 47306
85

The effects of total organic carbon and salt content of municipal solid waste leachate on zinc migration through soil

Boyle, Michael January 1980 (has links)
No description available.
86

Freezing and drying: effects on the solubility of municipal solid wate leachate constituents

Bitterli, Ronda Jo January 1981 (has links)
No description available.
87

SANITARY LANDFILL AREA RECOVERY IN SOUTHERN ARIZONA

Deming, Stephen Arthur, 1906- January 1971 (has links)
No description available.
88

Constructed wetlands as an appropriate treatment of landfill leachate.

Bricken, Elizabeth Colomb. January 2003 (has links)
One of the main environmental problems associated with the disposal of waste on land is the release of liquid emissions from the site. This wastewater, known as leachate, is a product of the biodecomposition of the waste and filtrates from the landfill once the moisture saturation of the fill has been reached. The chemical composition of leachate is variable over time and between sites. Regardless of these variables, the main pollutants of concern in the leachate are ammonia and organics, both of which can cause environmental degradation in relatively low concentrations. Worldwide and in South Africa, leachate has either been directly released into the environment or into the local domestic sewage system. As more has been learned about the human and environmental health risks associated with these disposal methods, there has been a new focus in waste management toward treating the leachate at the source as part of the broader focus of sustainable landfilling. One of the treatment options being used is constructed wetlands (CW) due to the physical and chemical transformation mechanisms in these biological systems. This treatment process has been demonstrated to be effective as a final polishing treatment for leachate, and it is considered a technology appropriate in the South African context. Therefore the aim of dissertation is to ascertain the use of constructed wetlands as an appropriate treatment option for untreated methanogenic landfill leachate by determining the efficiency of ammonia and organic removal in a pilot-scale vegetated submerged bed (VSB) constructed wetland (CW) planted with Phragmites australis. During the 22-week treatability trial the VSB achieved an ammonia concentration removal efficiency of 91% and mass removal efficiency of 87%. Despite this substantial reduction of ammonia, the VSB was unable to achieve the required discharge standard. There were erratic fluctuations in both the treatment efficiencies for COD and BOO, and the results show no evidence of constant reduction of organics during the treatability trials. This is due to the refractory nature and the low biodegradability of the organics that remain in methanogenic leachate as suggested by the low BOO to COD ratio. Due to the low biodegradability of the organics, a biological treatment system, such as a VSB, will not be able to reliably meet the required discharge standards. Other passive treatment options or a combination of systems need to be explored in order to both satisfy legislative requirements and be appropriate in the South African context. / Thesis (M.Sc.)-University of Natal, Durban, 2003.
89

Fate of selected organic pollutants during landfill codisposal with municipal refuse

Reinhart, Debra R. 05 1900 (has links)
No description available.
90

Co-disposal of low-level radioactive waste within sanitary landfills

Chang, Ker-Chi 12 1900 (has links)
No description available.

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