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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.
51

Preservation or exploitation? : a study of the development of the mining rights legislation on the Witwatersrand goldfields from 1886 to 2008

Stott, Joan January 2009 (has links)
Elinor Ostrom (2005: 238) assumes that in understanding the make up and behaviour of institutional systems governing natural resources: “Resource users are explicitly thought of as rational egoists who plunder local resources so as to maximise their own short-term benefits. Government officials are implicitly depicted, on the other hand, as seeking, the more general public interest, having the relevant information at hand and the capability of designing optimal policies.” This thesis examines the validity of this assumption through an historical analysis of the deep-level gold mining industry of the Witwatersrand, South Africa. The main focus of the assessment is on the institutions of ownership – that is, the development of mining rights and title legislation between 1886 and 2008. The study looks at the legislations’ transformation and implementation from the perspective of the gold mining industry – made up of the mining finance houses and the Chamber of Mines of South Africa – and that of the state. The transformation of the mining industry’s institutional framework was both a choice by government as well as that of the firms in the mining industry. The theoretical framework is constructed from four areas of economic thought. These include: the neoclassical and Keynesian schools of macroeconomic thought; industrial organisation and its relevance to the relationship between firms and the market; institutional and new institutional economics; and finally property rights. The determinants of policy design and the impact of such design on firms and industry is examined. The development, implementation and use of the aforementioned legislation is examined from two perspectives, namely, that of preserver or exploiter. Throughout the history of this prominent South African industry, the motivation for action from the industry or government has oscillated between the two extremes of preserver or exploiter over the time period examined. The conclusion is drawn on an overall and broad focus of actions – with a strong focus on the most recent developments in mining legislation – post-1992.
52

The stratigraphy, structure, and gold mineralization of the Jamestown and Sheba Hills areas of the Barberton Mountain Land

Anhaeusser, C. R. (Carl Robert) 28 May 2015 (has links)
No description available.
53

The contribution of leadership behaviour in creating a safety conscious organisational culture : a case study of Anglo American mining operations

McLeod, Ashley 12 1900 (has links)
Thesis (MBA (Business Management))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: In the 20th century, many employees in the South African mining industry were involved in occupational accidents which either resulted in personal injury or had fatal consequences. Despite the introduction of numerous industrial safety programmes to prevent fatal incidents and minor injuries, the South African mining industry death toll remains consistently high, at approximately 200 employees per annum. The trend of employee injury and death continues unabated into the new millennium. This safety performance has been met with growing dissatisfaction in the ranks of government, worker unions, employees and business stakeholders. This dissatisfaction is directed at chief executives who are being blamed for the occupational accidents on their mines. There is now growing focus on the leadership of mining companies and how it contributes to shaping an organisational culture for improved safety performance. The researcher examines whether leadership is a key component in creating a safety conscious organisational culture, and uses literature studies and the Anglo American mining company as a practical case study to support the investigation. Anglo American, listed on the Johannesburg and London stock exchanges is the largest mining company in South Africa and also one in which many fatal injuries have occurred; providing an abundance of safety information. The researcher reviews previous literature studies and explains the journey Anglo American undertook to improve its safety performance since listing on the London Stock Exchange in 1999. The concepts of organisational culture, safety culture, leadership and organisational performance, are discussed from a theoretical and practical perspective using literature studies. These are then examined with the ultimate view of understanding their practical impact on organisational safety as espoused in the literature. The literature provides a broad framework on which to assess Anglo American's safety journey from 1999 to the end of 2007. This journey details the safety programmes and efforts employed by Anglo American to eliminate fatalities and injuries and also highlights the impact of the organisation's leadership on the safety performance of the company. It is concluded that the contribution of leadership is pivotal to establishing a safety-conscious organisational culture and that specific behaviours from executives, senior managers, middle managers, supervisors and workers are needed to develop an organisations safety culture for improved safety performance. / AFRIKAANSE OPSOMMING: Gedurende die 20ste eeu was baie werkers in die Suid-Afrikaanse mynbedryf betrokke in beroepsverwante ongelukke wat tot persoonlike beserings of lewensverlies gelei het. Ten spyte van die instelling van veelvuldige beroeps-veiligheidsprogramme om noodlottige insidente en ander minder ernstige beserings te voorkom, bly die dodetal in die Suid-Afrikaanse mynbedryf konstant hoog, teen ongeveer 200 werkers per jaar. Hierdie tendens van dood en beserings onder werkers gaan ongetem voort tot in die nuwe millennium. Hierdie veiligheidsrekord word met toenemende ontevredenheid deur die regering, werkers-vakbonde, werkers en bedryfsinsethouers beskou. Hierdie ontevredenheid word gemik op uitvoerende bestuur, wie blameer word vir beroepsverwante ongelukke in hul myne. Daar word dus toenemend gefokus op die leierskap van mynmaatskappye en hoe dit bydra tot die skepping van 'n organisasiekultuur van verbeterde veiligheidsuitslae. Die navorser ondersoek die vraag of leierskap 'n kern komponent is in die daarstelling van 'n veiligheids-bewuste organisasiekultuur, en maak gebruik van literatuurstudies sowel as Anglo American mynmaatskappy as 'n praktiese gevallestudie om sy ondersoek te ondersteun. Anglo American is die grootste mynmaatskappy in Suid-Afrika en ook die een waar baie noodlottige ongelukke voorgekom het, en dus 'n groot bron van veiligheidsinligting kan voorsien. Die navorser hersien teoretiese literatuurstudies en verduidelik dan die optrede van Anglo American om sy veiligheidsrekords te verbeter sedert sy noteering op die Londonse Effektebeurs in 1999. Die konsep van organisasiekultuur, veiligheidskultuur, leierskap en organisasieprestasie, word bespreek vanuit 'n teoretiese en praktiese perspektief met behulp van literatuurstudies en hierdie word bestudeer met die uiteindelike doel om die praktiese impak daarvan in industrie te verstaan soos uiteengesit in die literatuur. Die literatuur voorsien 'n breë raamwerk waarteen Anglo American se veiligheidstog gemeet kan word vanaf 1999 tot einde 2007. Hierdie tog verskaf detail van hoe Anglo American veiligheidsprogramme gebruik het om noodlottigge ongelukke en beserings uit te skakel en beklemtoon ook die impak van die organisasie se leierskap op die veiligheidsrekord van die maatskappy. Die gevolgtrekking word gemaak dat die bydrae van leierskap kern is tot die daarstelling van 'n veiligheidsbewuste kultuur en dat spesifieke optredes van hoofbestuurders, seniorbestuurders, middelvlakbestuurders, opsieners en werkers nodig is om 'n veiligheidskultuur te bewerkstellig om veiligheid in maatskappye te verbeter.
54

Geochemical characterisation of gold tailings footprints on the Central Rand Goldfield

Netshiongolwe, Khathutshelo Emmanuel 05 1900 (has links)
Gold mining in the Witwatersrand Basin of South Africa has resulted in soil contamination due to the lack of sufficient environmental management plans for the tailings dumps and remnant footprints. Tailings reclamation as a strategy of reducing pollution in the Central Rand, for instance, has resulted in contamination of water systems by acid mine drainage (AMD). After removal of the tailings dumps, remnant material is left over on the tailings footprints and these contain significant amounts of pollutants that were initially in the tailings. Heavy rainfall during summer dissolves primary minerals and later in the dry season, secondary minerals are precipitated as efflorescent crusts on and nearby tailings dumps as well as footprints due to high evaporation. The efflorescent crusts can redissolve when it rains and form acidic, metal and sulphate-rich solutions due to their soluble characteristics. This study aimed to characterise tailings footprints in areas targeted for human settlements and office spaces to assess their potential to release left over toxic elements such arsenic (As), lead (Pb), copper (Cu) and zinc (Zn). The approach to the study involved characterisation of oxidised and unoxidised tailings material and secondary precipitates on both tailings dumps and footprints. This involved determining the mineralogical composition using Powder X-ray Diffraction (PXRD). Dissolution and leaching studies were also conducted on the material followed by determination of constituent elements using inductively coupled plasma optical emission spectroscopy (ICP-OES) and sulphates using ion chromatography (IC). The leaching solutions used included rainwater; dilute sulphuric acid at pH of 3.0 (a common leachate in such acidic soils); as well as plant exudates such as oxalic and citric acids. The leachate solutions were used to correlate the mineralogical composition of secondary precipitates and tailings footprints. Potential implications on humans following any accidental ingestion of the tailings or contaminated soils were assessed using gastric juices. The ecological risk factors and risk index together with the model to evaluate daily intake and different pathways to humans were used to assess the toxicity caused by exposure to contaminants in the materials. The experimental work was augmented by computer simulations based on geochemical modelling (using the PHREEQC geochemical modelling code) to determine the speciation of elements (and thus their potential lability and bioavailability), dissolution and formation of secondary mineral precipitates in the tailings dumps and footprints. The findings of the PXRD study showed that the mineralogy of the tailings and footprints was dominated by quartz (SiO2) and some minor minerals such as pyrite (FeS2), pyrophyllite (Al2Si4O10(OH)2), chlorite (Mg,Fe)3(Si,Al)4O10), mica (K(Mg,Fe)3 AlSi3O10(F,OH)2) while that of secondary precipitates was dominated by jarosite (KFe3+ 3(OH)6 (SO4)2), goethite (FeOOH), melanterite (FeSO4.7H2O) and gypsum (CaSO4.2H2O). Minerals obtained for the secondary precipitates were corroborated by geochemical modelling. Leaching results using rainwater with pH ranges from 3.5 to 3.9 showed that trace elements are released very slowly from tailings dumps and footprints and in small concentrations during rainy seasons as follows: As (1.5 mg/L-4.5 mg/L), Pb (3.5 mg/L-5.5 mg/L), Cu (4 mg/L-4.8 mg/L) and Zn (23 mg/L-44 mg/L). The release and mobility of Cu, Pb, Zn and As occurs quite markedly when secondary precipitates dissolve, making the immediate impacted environment unfavourable for plant growth and any habits in the vicinity. This was substantiated by simulated dissolutions and assessment of the resulting elemental speciation that pointed to the elements being distributed in bioavailable forms, implying potential uptake by plants (such as vegetables that may be cultivated on such impacted soils). The model was used to evaluate the daily intake and different exposure pathways and the results showed that children may daily intake 48.4 mg kg-1 day-1 and adults‟ 32.8 mg kg-1 day-1 . After 5 years (1825 days) of exposure more harm may be experienced and findings shows that kids are the most victims on these contaminated sites compared to adults. Both children and adults may absorb low levels of these toxic elements daily and after long time of exposure it may cause disease like cancer in their body which may lead to death. Pathways may be through inhalation and accidentally ingesting tailings soil that contain toxic elements. Drawing from the above findings, it will be important that tailings footprints that have been earmarked as land for development (residential or office space) be thoroughly assessed for potential release of toxic elements and high levels of acidity. Further reclamation aimed at reducing these hazards can then be implemented. / College of Agriculture and Environmental Sciences / M. Sc. (Environmental Science)
55

Assessment and management of environmental and socio-economic impacts of small-scale gold mining at Giyani Greenstone Belt

Magodi, Rofhiwa 18 September 2017 (has links)
MENVSC (Geography) / Department of Geography and Geo-Information Science / Artisanal and small-scale gold mining (ASGM) has devastating impacts on different parts of the environment and is a source of environmental degradation and contamination. ASGM degrades water resources, contaminate soil, sediments and water and lead to serious land degradation problems. ASGM activities are also associated with socio-economic issues such as child labour, prostitution and health and safety concerns. Insufficient understanding of the environmental and social problems of ASGM in Giyani Greenstone Belt has led to lack of mitigation strategies to reduce such problems. The main aim of this research was to assess and manage the environmental and socio-economic impacts of ASGM in Giyani Greenstone Belt. Remote sensing and GIS and Normalised Differential Vegetation Index were used to assess the effects of mining activities on vegetation cover. Assessment of the effects of ASGM on water, sediments and soil quality involved collection of samples in order to establish their physical and chemical properties. The concentration of toxic and trace metals were determined using Atomic Absorption Spectrometer (AAS) and X-ray Fluorescence (XRF) instruments. The pH meter was used to determine the pH level of the collected samples. Questionnaires, interviews and SPSS were used to assess socio-economic impacts of ASGM. The study culminated in devolvement of NDVI maps and this was used to assess the effects of ASGM on vegetation cover. Results showed that the mining activities in the area had caused extensive environmental degradation due to serious removal of vegetation cover in the site. ASGM had serious effects on soil, water and sediments quality such as environmental contamination by toxic and trace elements. Soil samples were found with high concentration of As, Cr, Cu, Ni, Pb and Zn as compared to the recommended South African Soil Quality and WHO threshold values for plants. It was found that Klein Letaba had high concentration of Ba, La, V, and Ce above the World Soil Averages for plants. Sediments were heavily contaminated with Cr, Ni, Pb, Zn, As and Ba as compared to the recommended standards prescribed by US EPA and WHO. The pH of water, soil and sediments samples collected from both mining sites were found to be strongly alkaline which affects the plants growth as well as aquatic flora and fauna. Socio-economic issues such as child labour, injuries, educational problems, health and safety issues, police disturbance, creation of jobs and income generation were identified at mine sites. ASGM had serious effect on vegetation cover through environmental degradation. ASGM also had serious environmental contamination by toxic and trace elements. ASGM had both positive and negative socio-economic issues at mining site which include employment opportunities, income generation, occupational health and safety, police disturbance and arrests and the use of child labour. Mine site rehabilitation is recommended in this study to reduce environmental degradation. The remediation of contaminated area by concentrated toxic and trace elements should be applied at both mining sites. ASGM should be legalised to enhance positive aspects of the mining such as increase in income generation and creation of more employment opportunities. However, there should be enforcement of mining policies to reduce social and environmental problems.
56

Evaluation of economic potential of gold tailings dams: case studies of the Klein Letaba and Louis Moore Tailings Dams, Limpopo Province, South Africa

Nemapate, Ndivhuwo 18 September 2017 (has links)
MESMEG / Department of Mining and Environmental Geology / See the attached abstract below
57

Evaluation of Nebulas Gold Deposit in Giyani Greenstone Belt, Limpopo Province, South Africa

Mavhungu, Mbofholowo Emmanuel 18 May 2018 (has links)
MESMEG / Department of Mining and Environmental Geology / Giyani Greenstone Belt is known to host significant amount of gold of which about 10 tonnes were extracted from the belt in the 19th century. Due to increased gold price and mining practices that make it economic to mine low-grade ore deposits, major gold deposits within the belt have been the main targets for exploration while Nebulas Prospect remain unnoticed. To make the Nebulas Prospect attractive for investment, its gold mineralization potential needed to be investigated. The main purpose of this study was to conduct assessment of the probable gold mineralization in the Nebulas Prospect and its economic viability. The specific objectives were to establish the gold mineralized zones within the Nebulas Prospect, develop a geological model showing the geometry and placement of gold in the subsurface, establish gold grade distribution and its economic implication, and select the most appropriate and practical mining method for exploitation of the established gold deposit. The research approaches used in achieving these objectives comprised of knowledge driven predictive modelling of Nebulas Prospect to derive prospectivity map demarcating the area with the potential of hosting gold mineralization. Magnetic survey was conducted in geological permissive areas, thereby establishing boundaries of mineralization, both lateral and vertical. Geological and subsurface gold grade distribution were carried out by means of trenching and pitting. The integration of the geological, geophysical and geochemical data using Geosoft 8.5 and ArcGIS 10.5 assisted in development of a gold deposit model that model illustrates distribution and concentration of gold. Results of the investigation reveals that Banded Iron Formation (BIF) dominates the southern part of the study area while quartz vein and schist dominate the northern part. The application of knowledge driven predictive modelling established mineral prospectivity map for Nebulas Prospect, which narrowed the potential area for further investigation. The area located outside the boundary of prospective area indicated low mineralization potential compared to highly mineralized zone within geological permissive boundary. The two mineralize zones which exits in the Nebulas Prospect are separated by pegmatite intrusion which is observed from magnetic data presentation. The gold is hosted within BIF, schist and quartz vein. The highest concentration observed value of 10.65 g/t is hosted in serpentine schist and lowest significant of 1.24 g/t in BIF. The gold grades are higher in schists than in BIF and quartz veins. The Nebulas Prospect present significant measured iv gold mineral resource with substantial economic potential. The evaluation of the technical aspects of the Nebulas Gold Deposit, which include grade and tonnage was estimated through longitudinal vertical section method. The gold hosted within Banded Iron Formation (BIF) comprise a measured gold resource of 6957.6 t at an average weighted grade of 2.22 g/t Au. However, the gold mineralization hosted within tremolite-mica schist, serpentine schist and quartz veins comprise a measured gold resource of 3919.37 t with average grade of 3.8 g/t Au. The Nebulas Gold Deposit contain a significant grade and tonnage. At an assumed currently economically mineable cutoff grade 1 g/t Au, Nebulas Prospect has a measured resource of 10877 t at a weighted average grade of 2.79 g/t Au. Analytical hierarchy process (AHP) was used to prioritize the factors affecting mining method selection and ranking of potential mining method, technically appropriate for the established gold deposit in Nebulas Prospect. Open pit mining method was identified as appropriated for extraction of the Nebulas Gold Deposit. / NRF
58

Towards sustainable economic development in the gold mining areas of South Africa and Ghana

Boaduo, Adwoa Pokuaa January 2017 (has links)
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering, 2017 / In many mineral resource rich African countries, mining activity makes a significant contribution towards the Gross Domestic Product (GDP) and economic growth. This stimulus gives the mining industry the potential to fuel growth and development. Although some mining areas have been able to experience positive economic growth, many have struggled to achieve and sustain economic development due to the inability to manage mineral wealth challenges. African mining regulatory bodies generally lack proper local planning, resulting in inadequate policy instruments to enable the sector to make a sustainable contribution towards economic welfare. This research investigates how mineral wealth can be used as a catalyst for sustainable economic development. The research presents the case studies of three mining areas with the aim of determining why the economic development of Johannesburg differs substantially from that of Tarkwa and Obuasi. The research gives a comparative analysis of the political economy and socio-economic trends that have transpired in the three areas over the years. It ends by making recommendations on how Tarkwa and Obuasi can better manage the challenges of mineral wealth, and work towards achieving sustainable economic development that is like or even better than that of Johannesburg / CK2018
59

Law enforcement in the South African Gold Mining sector : the nexus between company, environmental and equity law

Lombard, Dewan 08 1900 (has links)
Although the mining industry contributed to the development of the country by providing infrastructure and employment, it left a negative impact on the environment. To this end, various pieces of law were promulgated to limit environmental damage and hold those who pollute (Mining Companies / licensees) accountable. This research focused on two study sites namely Blyvooruitzicht and Grootvlei gold mines. Both mines underwent forced mine closure and their environmental liabilities remained unresolved. This study focused on important laws governing the South African gold mining sector, to form an understanding of these laws and to establish if these laws protect the environment sufficiently or not. The study included an overview of the current relevant legislative framework regarding mines, with the aim of identifying if there were gaps between Mining law, Company law, B-BBEE law (Equity Law) and Environmental law. This included an exploration of the interrelationships between the various pieces of legislation and the challenges relating to compliance and enforcement of these mentioned laws. Further to this, the research study investigated the requirements and responsibilities of the South African State, and directors of mining companies. The finding was that South African law with respect to mining companies needs minor adjustments, but the crux of the problem is a lack of effective implementation and enforcement by the State. There is ineffective administration of environmental quality control by the various designated National Government Departments. Recommendations made include the need for clear monitoring of compliance and enforcement of the environmental regulatory framework if there is to be successful mine closure in South Africa. In addition, the South African State Government could consider incentivizing compliance, that is, reward mining companies who uphold environmental law. Further to this the thesis suggest the elimination of any contradictions between the various legislations within the mining industry and stipulates that legislation must be read in conjunction with one-another if a robust legislative framework is to exist. / Environmental Sciences / M.Sc. (Environmental Science)
60

Interaction of gold mine taillings leachates with soil and geochemical partitioning of toxic metal species

Ngoetjane, Pitsi Christopher 02 February 2016 (has links)
Department of Ecology and Resource Management / MENVSC

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