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

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

Dissertation submitted in compliance with the requirements for the Master's Degree in Technology: Biotechnology, Technikon Natal, 2001. / Landfills play an important role in the removal of waste from the surroundings. There is a limit to the types of waste that can be recycled and the landfill becomes the final method of waste disposal. Because waste constitutes a wide variety of materials, the microbial consortia that develop within a landfill will be equally varied, depending on the type of waste deposited, the temperature of the landfill and moisture content of the waste. The metabolism of these microbial consortia can result in products that are either harmful or beneficial. In order to increase the pool of knowledge on landfill microbiology, it is important to study the various consortia that inhabit the landfill to determine the various microbial interactions that occur and subsequently to manipulate these interactions to enhance the benefits of a landfill site and reduce the harmful effects. In this research, an attempt was made to isolate anaerobic cellulolytic bacteria from a landfill site. Six waste samples, varying in age were obtained over a period of two years. Samples were excavated from a maximum depth of 4m. Samples are processed in anaerobic, phosphate buffer and cultivated in various pre-reduced anaerobic media and incubated under anaerobic conditions. Samples were also collected from other potential anaerobic sites namely, anaerobic sludge, decomposing bagasse, compost, manure, rumen and pond sediment. Results of degradation of the cellulose source (Whatman No. 1 filter paper) indicated that it was possible to cultivate cellulose-degrading microorganisms from the landfill. Zones of clearing around colonies, which would be indicative of cellulose degradation on solid media, were not obtained. Samples from the anaerobic sludge, compost and rumen showed degradation of cellulose in liquid media but not on solid media. It is concluded that the solid media used was unsuitable for the cultivation of anaerobic, cellulolytic bacteria or that the anaerobic conditions employed were not adequate to initiate the growth of the anaerobic cellulolytic bacteria. / M

Este trabalho descreve os diversos materiais que podem ser utilizados nas tubulações de sistemas de esgotos sanitários, apresenta suas principais características, a hidráulica das tubulações, principais fabricantes, aspectos construtivos, operação e manutenção e comentam-se as normas técnicas referentes a esses materiais. Os dados apresentados foram obtidos através de pesquisa na área norte de São Paulo cujo sistema é operado pela Sabesp, consultando-se as unidades funcionais de projeto, apoio técnico, operação, manutenção e obras da Sabesp. Destaca-se a preferência pelo uso das tubulações de PVC para a implantação e manutenção das ligações prediais e redes coletoras devido às vantagens de sua aplicação, tais como: facilidade de transporte e manuseio, maior produtividade, menos problemas operacionais, praticidade e segurança. Para coletores de maiores diâmetros e interceptores há preferência pelos tubos de PRFV, PVC e PEAD e pelo sistema de tubo de concreto cravado. Na escolha do melhor material a ser utilizado, deve-se considerar além das características dos esgotos, a resistência, a disponibilidade, a facilidade de transporte, e custos desse material . Deve-se, também se levar em conta, o método aplicado na construção e as condições locais da obra. Como principais conclusões, destaca-se a viabilidade econômica da utilização do PVC em relação ao tubo cerâmico nas obras de redes e ligações, e a tendência da utilização de PRFV e PEAD na implantação de novos coletores com diâmetro de 300 a 500mm. Recomenda-se a utilização de juntas elásticas nas tubulações cerâmicas e a especificação do tipo de material precedida de estudos amplos de viabilidade que considerem a sua vida útil, praticidade de aplicação, custos, aspectos ambientais, operação, manutenção, segurança e rapidez na implantação da obra. / This dissertation describes the various materials used in sanitary sewer systems, presents their main characteristics, pipeline hydraulics and manufacturers. It also features construction, operational and maintenance aspects for the different materials as well as the technical regulations concerning these materials. Data were collected in the Northern area of São Paulo, whose sewer system is operated by Sabesp, through research in the following functional units: project, technical support, operations, maintenance and construction. This study highlights the operation area\'s preference for PVC pipes for building and maintenance of sewage connections and sewers because its advantages such as: ease of transportation and handling, greater productivity, less operational problems, practicity and safety. For large diameter trunk sewers and interceptors, FRP (Fiberglass reinforced plastic), PVC (Polyvinyl chloride) and PE (Polyethylene) pipes and Jacking Pipe system are usually the choice. In the selection of the best material, one should consider the wastewater characteristics and the material resistance, availability, ease of transportation and cost. The construction methods and local conditions should also be taken into account in this process. In conclusion, this study stresses the economical viability of PVC pipes over ceramical pipes in sewers and connections, the tendency to use FRP and PE in new 300 - to 500- mm- diameter trunk sewers and recommendation for the use of elastic joints with ceramical pipes. Lastly, the specification of the type of material to be used should be preceded by broad viability studies that consider its required life, practicity, cost, environmental aspects, operational and maintenance aspects and safety in the building process.

Lui Mei-kam. / Thesis submitted in: December 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 156-175). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.v / List of Plates --- p.ix / List of Tables --- p.x / List of Figures --- p.xiii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Waste Management in Hong Kong --- p.1 / Chapter 1.2 --- Landfilling of Wastes --- p.3 / Chapter 1.3 --- Waste Degradation and Landfill By-Products --- p.3 / Chapter 1.4 --- Revegetation Problems on Post-Closure Landfills --- p.9 / Chapter 1.4.1 --- Compact and shallow soil --- p.9 / Chapter 1.4.2 --- Drought --- p.10 / Chapter 1.4.3 --- Nutrient deficiency --- p.10 / Chapter 1.4.4 --- Toxicity --- p.11 / Chapter 1.5 --- Ecosystem Development on Post-Closure Landfills --- p.11 / Chapter 1.6 --- Site Description --- p.13 / Chapter 1.7 --- Objectives --- p.20 / Chapter Chapter 2 --- Chemical Properties of Cover Soil on the Pillar Point Valley Landfill / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Materials and Methods --- p.25 / Chapter 2.2.1 --- Soil collection and analysis --- p.15 / Chapter 2.2.2 --- Statistical analysis --- p.26 / Chapter 2.3 --- Results and Discussion --- p.26 / Chapter 2.3.1 --- Soil properties --- p.26 / Chapter 2.3.1.1 --- Organic carbon --- p.26 / Chapter 2.3.1.2 --- pH --- p.28 / Chapter 2.3.1.3 --- Electrical conductivity --- p.29 / Chapter 2.3.1.4 --- Nitrogen --- p.29 / Chapter 2.3.1.5 --- Phosphorus --- p.31 / Chapter 2.3.1.6 --- Potassium --- p.32 / Chapter 2.3.1.7 --- Cation contents --- p.33 / Chapter 2.3.2 --- Development of soils after revegetation --- p.33 / Chapter 2.3.3 --- Implications of soil property to vegetation development --- p.34 / Chapter 2.4 --- Conclusions --- p.36 / Chapter Chapter 3 --- Vegetation Composition and Development on the Pillar Point Valley Landfill / Chapter 3.1 --- Introduction --- p.37 / Chapter 3.2 --- Materials and Methods --- p.38 / Chapter 3.2.1 --- Vegetation cover --- p.38 / Chapter 3.2.2 --- Floristic analysis --- p.39 / Chapter 3.2.3 --- Statistical analysis --- p.41 / Chapter 3.2.3.1 --- "Diversity, evenness and similarity of sites" --- p.41 / Chapter 3.2.3.2 --- Association of species and of quadrats --- p.42 / Chapter 3.2.3.3 --- Classification of species --- p.43 / Chapter 3.3 --- Results and Discussion --- p.43 / Chapter 3.3.1 --- Vegetation descriptions and analysis --- p.43 / Chapter 3.3.1.1 --- General vegetation cover --- p.43 / Chapter 3.3.1.2 --- Floristic composition --- p.46 / Chapter 3.3.1.3 --- Ecological indices between sites --- p.61 / Chapter 3.3.2 --- Species distribution along soil properties --- p.64 / Chapter 3.3.3 --- Ecological development on landfills --- p.73 / Chapter 3.3.3.1 --- After hydroseeding --- p.73 / Chapter 3.3.3.2 --- After tree planting --- p.74 / Chapter 3.4 --- Conclusions --- p.76 / Chapter Chapter 4 --- Seed Bank Composition and Development on the Pillar Point Valley Landfill / Chapter 4.1 --- Introduction --- p.78 / Chapter 4.2 --- Materials and Methods --- p.79 / Chapter 4.2.1 --- Seed collection --- p.79 / Chapter 4.2.2 --- Seed germination --- p.80 / Chapter 4.2.3 --- Statistical analysis --- p.81 / Chapter 4.3 --- Results and Discussion --- p.81 / Chapter 4.3.1 --- Seed bank composition and analysis --- p.81 / Chapter 4.3.1.1 --- Seed bank composition --- p.81 / Chapter 4.3.1.2 --- Ecological indices between sites --- p.94 / Chapter 4.3.1.3 --- Similarity between seed banks and standing crops --- p.96 / Chapter 4.3.2 --- Seed characteristics on the four sites --- p.100 / Chapter 4.3.2.1 --- Grasslands --- p.100 / Chapter 4.3.2.2 --- Woodlands --- p.102 / Chapter 4.3.3 --- Ecological development on landfills --- p.103 / Chapter 4.3.3.1 --- After hydroseeding --- p.103 / Chapter 4.3.3.2 --- After tree planting --- p.109 / Chapter 4.3.4 --- Performance of planted trees --- p.113 / Chapter 4.4 --- Conclusions --- p.115 / Chapter Chapter 5 --- Ecophysiological Studies on Three Selected Tree Species on the Pillar Point Valley Landfill / Chapter 5.1 --- Introduction --- p.117 / Chapter 5.2 --- Materials and Methods --- p.120 / Chapter 5.2.1 --- Field measurements --- p.120 / Chapter 5.2.2 --- Statistical analysis --- p.121 / Chapter 5.3 --- Results and Discussion --- p.121 / Chapter 5.3.1 --- Soil factors --- p.121 / Chapter 5.3.1.1 --- Soil moisture content --- p.121 / Chapter 5.3.1.2 --- Soil gas composition --- p.123 / Chapter 5.3.2. --- Ecophysiological expressions --- p.129 / Chapter 5.3.2.1 --- Fv/Fm --- p.129 / Chapter 5.3.2.2 --- Stomatal conductance --- p.134 / Chapter 5.3.2.3 --- Transpiration --- p.139 / Chapter 5.3.3 --- Implications of ecophysiological studies --- p.146 / Chapter 5.4 --- Conclusions --- p.149 / Chapter Chapter 6 --- General Conclusions --- p.150 / References --- p.156

published_or_final_version / Architecture / Master / Master of Landscape Architecture

The body of work presented in this Thesis document provides a comprehensive examination of final cover design for municipal solid waste landfills. Accompanying general design principals is the investigation and resulting recommendations for issues specific to the closure of the Vancouver Landfill. The first objective of the Thesis was to develop a set of physical characteristics for soil materials, which would allow for the construction of a lowpermeability barrier layer meeting British Columbia guidelines. The second objective was to then use the developed soil criteria to evaluate the suitability of Lower Mainland soils. The physical characteristic of soil material, originating from trench excavations in Vancouver, was closely examined and the material evaluated for use in all layers of final cover design. The last objective of the Thesis was to investigate the use of alternative cover materials, including geosynthetics, in final cover design. The combination of a comprehensive literature review and the implementation of a program of soil sample collection and analysis allowed for the completion of the above objectives. Testing of soil samples included the determination of the grain size distribution to the clay fraction level. The major findings of the work are that soil sources in the City of Vancouver are not suitable for use in the construction of a low-permeability barrier layer. Suitable soil sources however, can be found in areas of Surrey and Langley. Trench excavation soil is recommended for use in the foundation layer of the final cover. Lastly, geosynthetic materials are a viable alternative to the use of soil in final cover design. A polyvinyl chloride (PVC) geomembrane would be the most suitable geosynthetic based barrier layer for the requirements of the Vancouver Landfill.

This project examines a sanitary landfill's potential for end-use development. The main purpose is to demonstrate that landfills that have been sited and operated without the development of an end-use plan will have much less end-use potential than those landfills that were sited with an end-use as a major objective.The project consists of three basic stages, introduction, background, and case study. The introduction outlines the project, stating the purpose, the limitations and assumptions, and goals and methods. The background section presents basic information pertaining to solid wastes management and planning, landfill siting and design, and end-use considerations. The case study presents an analysis of the Madison County Landfill in an attempt to demonstrate the end-use potential, or lack of potential, as a recreation facility. In addition to these three sections, there is also an evaluation of the project and a summary and conclusions. / Department of Landscape Architecture

Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 222-238).

Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 107-112).