Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (p. 379-394). Also available in electronic version.

Virginia is rapidly running out of landfill space. Recycling is seen as a way to alleviate some of the burden on our landfills. The Commonwealth of Virginia has mandated an ambitious recycling goal of 10% of our municipal solid waste (MSW) by 1991, 15% by 1993, and 25% by 1995. Yardwaste (debris such as leaves, grass clippings and shrub and tree prunings) comprises an estimated 15% to 20% of the municipal solid waste going into our landfills daily. Yardwaste can be recycled by collecting the material, piling it into large windrows, and allowing it to decompose by a controlled process called composting. The finished product can then be utilized as a soil amendment for use by nurseries, landscapers, farmers, local and state government landscaping projects, and by homeowners. The Virginia Cooperative Extension Service at Virginia Tech was authorized to perform a study on the feasibility of implementing a statewide yardwaste composting program for Virginia. The methods involved in the study included information acquisition via a literature review, site visits in other states to assess technologies and a series of surveys to determine potential uses and users of composted yardwaste in Virginia. The feasibility study was presented to the Virginia Department of Waste Management in November 1989 and presented as House Document No. 34 to the 1990 Session of the Virginia General Assembly. Several pieces of legislation, including three bills and one joint resolution, are currently pending concerning the results of the study. / Master of Science

The design characteristics of an active waste disposal capsule placed within a saturated groundwater environment is investigated, with the objective of developing a methodology to determine environmentally, technically and economically feasible conditions for its operation. In operation, conditions are created and maintained within and surrounding a containment cell to insure that a potential for convective inflow exists everywhere across an encapsulating barrier which tends to counter the potential for outward dispersion through the barrier. A computer algorithm based on the finite element method has been developed in the BASIC language to aid in the hydraulic analysis. Essentially, it provides a numerical solution to potential flow through porous media for two dimensional anisotropic solution domains of various materials. Data generated from this algorithm for cases of varying geometric material and boundary properties are used to verify and quantify assumed relationships involving critical design parameters which have been developed through dimensional analysis and physical reasoning. An expression describing the concentration profiles developed across the barrier is obtained by solving the one-dimensional convection-dispersion equation for steady conditions within and bounding the capsule barrier. Applying this result to an identified critical point allows conservative barrier design criteria to be developed so that operation of the active capsule results in only negligibly small amounts of contamination escaping through the barrier to the environment. By introducing cost coefficients which are descriptive of various aspects of construction, operation and maintenance of the active capsule, a total cost function is formulated from which, when minimized with respect to various design variables, optimizing criteria are developed. Finally, a predictor-corrector optimization program which incorporates the results of this study is developed and used to investigate an illustrative problem. / M.S.

published_or_final_version / Architecture / Master / Master of Landscape Architecture

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements of the degree of Master of Science in Geology Johannesburg, 1998 / This study determines the potential of prerncting pollution to ground water by sanitary landfills. The tracing capabilities of both stable and radioactive environmental isotopes are also evaluated. Four landfills were selected, the Linbro Park and Waterval sites in Johannesburg, and the Bloemfontein northern and southern landfill sites. The sites all differ in geological environment, size. age and physiographic setting. [Abbreviated Abstract. Open document to view full version] / MT2017

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / abstract / toc / Civil Engineering / Master / Master of Philosophy

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 241-249). Also available in electronic version. Access restricted to campus users.

Thesis (M.S.)--Florida State University, 2006. / Advisor: Jeffrey Chanton, Florida State University, College of Arts and Sciences, Dept. of oceanography. Title and description from dissertation home page (viewed Sept. 26, 2006). Document formatted into pages; contains ix, 84 pages. Includes bibliographical references.