[Truncated abstract] Mine lakes are a water body created after an open-cut mine ceases operating. The lakes develop in the former mine-pit due to the combination of groundwater inflow, surface run-off and, in some cases, due to rapid filling from river diversion. While potentially valuable water resources, these lakes often have poor water quality and managing the water body is an important part of the overall process of mine site rehabilitation. As mine lakes form in man-made pits, they have a bathymetry that is typically quite distinct from natural lakes and this can, in turn, strongly influence the hydrodynamics and hence the water quality of the water body. Despite the potential importance of these water bodies, there have been very few studies on the hydrodynamics of mine lakes. This study describes a field investigation of the hydrodynamics of a former coal mine lake, Lake Kepwari, in south-western Western Australia. In particular, this study examines the hydrodynamic processes in both the surface mixing layers and the internal mixing in the density stratified lake. Wind sheltering in the surface mixing layer occurs due to the presence of the steep walls and lake embankments. A week long field experiment was conducted in December 2003 using a combination of moored thermistor chains with meteorological stations and the deployment of rapid vertical profiling turbulent microstructure instruments and CTD drops from two boats operating on the lake. ... Simulations indicated that inclusion of a site specific sheltering effect, based on the results of the field campaign, significantly improved the models‘ performance in capturing the surface mixed layer deepening associated with episodic strong wind events that occur on the lake. Considerable internal mixing was indicated by the high dissipation rates observed, particularly near the boundaries. Large basin-wide diffusivities were also calculated from the heat budget method over long periods, showed a consistency with time, and were slightly higher in summer than during the Autumn Winter period. Although light, there are persistent winds over the lake and yet little basin-scale internal wave activity or seiching. It is hypothesized that any seiching motion was rapidly damped by strong mixing over the hydraulically rough bathymetry bathymetry created by the remnant benches from the open cut mining operation itself. This boundary mixing, in turn, drives secondary relaxation currents that transport mixed fluid from the boundaries to the interior, resulting in high effective basin-wide diffusivities. A simple boundary mixing model is proposed to describe this process.

Thesis (M.S.)--University of Tennessee, Knoxville, 2008. / Title from title page screen (viewed on Feb. 26, 2009). Thesis advisor: Mark Littmann. Vita. Includes bibliographical references.

Magister Scientiae - MSc / The objective of this study was to investigate the feasibility of the application of low cost high capacity inorganic ion exchange material, synthesized form collected fly ash and acid mine drainage solid residues, for the decontamination of secondary co-disposal process waters, with emphasis on investigating the processes governing the solid/solution interface. / South Africa

This research investigates cases of learning pathways for improving rehabilitation practices for key occupations in the mining industry. The study is set up as a partnership research programme between Rhodes University Environmental Learning Research Centre in South Africa, and the South African Qualification Authority, focussing on workplace learning and sustainability practices. This research programme seeks to understand the implications of the move to a knowledge society, with its emphasis on knowledge building over time, particularly in and for the environmental sector. The research was conducted as a qualitative case study that made use of semi-structured interviews, document analysis, visual photographs and observations as instruments of data gathering. Participants were sampled from two case studies, one in Limpopo province and the other one in Mpumalanga Province, who are directly involved in rehabilitation practices and related education and training programmes. The study makes use of career stories from the key occupations to provide insight into workplace learning pathways to inform education and training in the mining industry. A series of analytical statements captures some of the main findings on early education histories, career choices, learning pathway decisions and experiences related to sustainable practices and some complexities related to learning pathways. Environment and sustainability education is a cross-cutting issue in the NQF; and it pertains to the mining sector, especially to rehabilitation practices, which form the focus of this study as little is known about learning pathways associated with these sustainability practices. Insights from the study should enable the sector to enhance rehabilitation training for key occupations and at the same time encourage lifelong learning contributing towards sustainable development.

This research investigates the characteristics of natural resource mega-project planning processes. The implications of staple theory and selected characteristics of natural resource mega-projects are used to construct eleven characteristics of such planning processes. Staple theory suggests that optimistic expectations will be a fundamental characteristic of resource development planning in Canada, and that the state's role will be to facilitate, rather than evaluate, staple production. The size, complexity, visibility, and meaning of mega-projects may create momentum around them that weakens rational analysis and stampedes the planning process. Overall, the planning process may focus on narrow, technical issues concerned with constraints facing the mega-project. Alternatives may not be considered, overly optimistic expectations may not be checked, and risk and uncertainty may be inadequately addressed. These proposed planning process characteristics are investigated in a case study of British Columbia's North East Coal Project (NECP). The institutional structure of the planning and implementing organizations are investigated, and the major planning issues are identified. The expectations generated within the planning process regarding the mega-project's contribution to regional economic growth and development, and its economic viability are reviewed, and then evaluated by comparing them to information available at the time from sources within the planning process and from sources outside the planning process, and to actual outcomes. The case study findings support many of the eleven proposed characteristics of natural resource mega-project planning processes. The NECP's public planning process focused on identifying and overcoming constraints that would prevent the mega-project proceeding, and on minimizing the costs of the public sector's infrastructure responsibilities in the mega-project. The terms of reference for the various Sub-Committees requested analyses of constraints in most cases. The absence of a Regional Development Sub-Committee in the organization of the planning task force suggests that longer term planning issues were not perceived to be as important as the infrastructure issues. Sixty percent of the official public planning budget was allocated to transportation and townsite studies. The mandate, structure and operations of the government's implementing organization focused on controlling project costs. Finally, the benefit-cost analysis of the mega-project did not consider any alternatives to the NECP. The expectations regarding the NECP's contribution to regional economic growth and development were overly optimistic given the information available at the time, and far exceed the actual outcomes to date. The NECP stabilized the South Peace region during the recession of the early 1980s, and produced some growth in employment, population, and income levels. Also, education levels increased and some entrepreneurial development occurred. However, the mega-project did not alleviate the unemployment situation in the region, did not improve the distribution of income, and it did not diversify the regional economic structure. Despite the early planning emphasis given to the opportunities that the NECP could provide to members of regional target groups such as Natives and women, few individuals from these groups obtained mining employment. In 1986, most of the direct economic benefits associated with the NECP, such as the new employment opportunities, high incomes, and training opportunities, had been captured by in-migrants to the region. The expectations regarding the NECP's economic viability were also overly optimistic given information available at the time. The possibility of capital cost overruns were not considered despite ample indication that they were highly probable. Continuing high prices were assumed despite historical evidence that periods of high prices had been consistently followed by sustained periods of low prices, and expert advice that structural forces would contribute to a continual decline in the Japanese demand for metallurgical coal. The pre-project analysis projected that the NECP's net present value would be $464 million (1980$C), but the ex post analysis suggests that the NECP will generate $955 million (1980$C) in net economic losses for the Canadian economy. The overly optimistic expectations regarding the NECP's economic viability were formed early in the planning process and were based on a period of enormous increases in metallurgical coal prices. As market conditions changed, the group within the planning task force responsible for the NECP's economic evaluation lowered their expectations, but their concerns were apparently insufficient to counter the momentum that had been established around the NECP. This momentum was reinforced by the meaning attached to the NECP, which was portrayed as a fundamental component of BC's economic development strategy. Risk and uncertainty were inadequately addressed within the planning process and within the technical analyses of this mega-project's regional economic impacts and economic viability. No sensitivity analyses were completed in the analysis of the NECP's regional economic impacts. The sensitivity analyses in the pre-project benefit-cost analysis all considered positive adjustments to the base case scenario, save one. Problems of geological uncertainty, and the lack of experience of the project proponents in coal mining were ignored. Mega-project planning processes must be carefully designed to counter the characteristics suggested by this research. At a minimum, a full public review of the mega-project should be conducted before the decision to proceed is taken. Consideration should be given to developing a formal, required mega-project planning process based on the two-tiered structure. The first tier would include a policy assessment addressing broad questions such as alternative regional development strategies. If the outcome of the first tier was a decision to proceed with a mega-project, the second tier would address mega-project planning and regulatory issues such as infrastructure options and impact management strategies. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

Depuis 2006, l’arrêt des pompages d’exhaure dans le Bassin Houiller Lorrain (France) a conduit à l’ennoyage des travaux miniers abandonnés, avec pour conséquence la mise en place d’un nouvel équilibre hydrodynamique régional. De récentes recherches portant sur l’exploitation de la chaleur des réservoirs ennoyés ont suscité de nouvelles interrogations, auxquelles nous nous sommes proposé de répondre. Notre travail avait pour objectif de chercher à comprendre le comportement thermo-hydrodynamique de l’eau de mine au sein d’un système en cours d’ennoyage ou récemment ennoyé. Dans un premier temps, les contextes géographique, géologique et hydrogéologique du Bassin Houiller Lorrain ont fait l’objet d’une synthèse, et une zone d’étude a été choisie. Dans un second temps, des profils de température et de conductivité électrique, complétés par des jaugeages, ont été mesurés dans d’anciens puits de mine du Bassin Houiller Lorrain, offrant une meilleure compréhension du comportement de l’eau à l’échelle d’un ouvrage profond. À partir de l’analyse de ces données, un modèle thermo-hydrodynamique et des simulations numériques ont pu être réalisés à cette échelle. Les résultats permettent d’expliquer les phénomènes observés. Leur stabilité est également étudiée. Dans un troisième temps, un modèle spatialisé maillé a été construit pour aborder la problématique du comportement hydrodynamique d’un réservoir minier entier. La montée de l’eau observée a été correctement reproduite ; le modèle peut par ailleurs être utilisé de façon prédictive pour la période suivant l’ennoyage. Plusieurs outils ont été testés, améliorés ou développés afin de faciliter l’étude des réservoirs ennoyés, notamment concernant l’homogénéisation tridimensionnelle des conductivités hydrauliques et le couplage d’un modèle spatialisé maillé avec un réseau de drains-conduits / Since 2006, cessation of dewatering in Lorraine Coal Basin (France) led to the flooding of abandoned mines, resulting in a new hydrodynamical balance in the area. Recent researches concerning geothermal exploitation of flooded reservoirs raised new questions, which we propose to answer. Our work aimed to understand the thermo-hydrodynamical behaviour of mine water in a flooding or flooded system. Firstly, we synthetized the geographical, geological and hydrogeological contexts of the Lorraine Coal Basin, and we chose a specific area for our studies. Secondly, temperature and electric conductivity log profiles were measured in old pits of the Lorraine Coal Basin, giving a better understanding of the water behaviour at a deep mineshaft scale. We were able to build a thermo-hydrodynamical model and simulate water behaviour at this scale. Flow regime stability is also studied. Thirdly, a hydrodynamical spatialized meshed model was realized to study the hydrodynamical behaviour of a mine reservoir as a whole. Observed water-table rise was correctly reproduced : moreover, the model can be used in a predictive way after the flooding. Several tools were tested, improved or developed to ease the study of flooded reservoirs, as three-dimensional upscaling of hydraulic conductivities and a coupled spatialized meshed model with a pipe network

MESMEG / Department of Mining and Environmental Geology / The future of energy in South Africa depends on coal as it is one of the cheapest and most affordable sources of energy; however, some of the coal is uneconomical to mine due to the thickness and depth of the coal seams. For many years the coal resources of the Soutpansberg Coalfield remained untapped and limitedly researched and with the coal resources running out in the other coalfields, the Soutpansberg Coalfield remained the bright coalfield of tomorrow in South Africa. Coal seams in the Soutpansberg Coalfield occur within the Madzaringwe Formation. Three coal basins have been identified in this coalfield, are the Venda-Pafuri, Tshipise and Mopane. Sedimentological basin analysis of the coal stratigraphy and characterisation of the Soutpansberg Coalfield in the Makhado area, Limpopo Province was investigated within the farms of Rissik, Fannie, Duel, and Lurkin. The main purpose of the study was to establish the variation of the coal stratigraphy and how coal influenced the stratigraphy within the area. Fieldwork involved core logging and core sampling from the different farms within the Makhado coal area, while laboratory work included petrographic studies, investigation of the physical and chemical properties of coal. Core logging revealed the occurrence of coal zones where coal seams were intercalating with mudstones, but rarely with siltstone that formed the footwall of coal. Rarely was coal intruded by dolerite dyke as was the case along borehole W6610001. Core logging further revealed the sedimentary structures in the lithologies and the depth at which different lithologies were intersected. From these sedimentary structures, the environment of coal deposition was deduced supported by the geochemical analysis of major oxides and trace elements. Correlation of boreholes along the strike showed that the shale and mudrock were the predominant rocks within the coal horizon leading to the conclusion that these were the coal host rocks. Whole rock geochemical analysis was undertaken, using X-Ray Fluorescence Spectroscopy in order to establish the rock types and their trace element contents. The collected samples were analysed at the University of Venda, Department of Mining and Environmental Geology Laboratory, Siza Coal Services in Secunda and Council for Geoscience. The study indicated that the coal seams of the Soutpansberg Coalfield were deposited within the floodplain of a mixed-load fluvio-deltaic (fluvial and braided) systems. This sedimentary channel has been the major influence on the development of the coal seams. Locational changes in sedimentary facies above and below the coal seams within the study area has caused variations in the rates of compaction and subsidence which influenced the coal basin morphology and the coalification pattern. These two parameters (variations in the rates of compaction and subsidence) controlled the coal quality parameters, and coal seam thickness as well as the coal composition. The study confirmed that coal quality and thickness vary markedly from place to place in this coalfield due to varying local depositional environments. Most of the drill holes intersected mainly 3 coal seams, although in some cases either 2 or 5 seams were intersected. The thickest coal seam (borehole F578002) was 8 m. It was concluded that the coal was sub-bituminous to bituminous coal rank class (medium-volatile bituminous coal rank class). The coal had low moisture content ranging from 0.7-0.8%, and ash content ranging from 21.4-32%. The fixed carbon and volatile matter values of the coal samples ranged from 42.5 to 50.4% and from 25.2 to 27.4% respectively. The carbon and hydrogen were the main principal combustible elements in coal, however; carbon is the predominant one based on weight, constituting about 5.3% (the lowest) to 70.3% (highest) of the total. Due to the nature and thickness of the coal seams we conclude that this coal was economical to be mined and can be used for electricity generation and in cement grinding plants. A graph of coal gas concentrations over combustion time showed that methane (CH4) and carbon dioxide (CO2) had high gas concentrations, amounting to 1.75% and 1.70% respectively. / NRF

No description available.

M.Sc.(Eng.), Faculty of Engineering and the Built Environment, University of the Witwatersrand, 2011

A thesis submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Doctor of Philosophy. Johannesburg, March 2017. / This thesis follows the development of a particular set of large technical systems in South Africa from the late apartheid era into the age of democracy. During apartheid technological prowess, upheld by the network of state corporations or parastatals, bolstered the authoritarian rule of the white minority government in South Africa. The economic and political liberalisation of the late 1980s challenged the power of the parastatals and altered the underlying rationale of infrastructure development. In particular I describe the transformation of Iscor and Eskom, two of the country’s major parastatals, and their activities in the Waterberg coalfields, an isolated region on the country’s north-western border. While Eskom’s activities in the region began in the 1980s they gained public notoriety with the construction of the Medupi power station two decades later. The obstacles that Eskom faced at Medupi represent the main challenge of developing large technological infrastructures in the democratic, post-colonial order, where the fruits of infrastructure development demand to be spread beyond the bounds of an elite minority. But the eventual completion of some power generating units in 2015 at Medupi demonstrates that failure is not inevitable. I argue that this success is due to the fact that the autonomous parastatal network negotiated the political and economic liberalisation of the early 1990 by incorporating the changing socio-political conditions into its operations. The parastatal network retained a momentum, in the sense first described by the historian of technology Thomas Hughes, which was also a product of the “locked-in” nature of investment in the infrastructure project. Because of the large capital investment required for the infrastructure development, proceeding tenaciously against the odds to see the project to completion was cheaper than retreat for those involved. / MT2018