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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.
141

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)
142

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
143

Knowledge, attitude and practice of coal mineworkers pertaining to Occupational Health and Safety at the Leeuwpan Mine in Mpumalanga Province, South Africa

Mavhunga, Khuthalo 21 September 2018 (has links)
MPH / Department of Public of Health / The occupational health and safety of coal mine workers is one of the major occupational challenges in the mining industry. Coal mine workers face the looming perils of potential falls of volatile rocks, the ergonomic challenges caused by bending and lifting heavy objects in their daily work, the challenges caused by inhaling coal mine dust which can cause coal workers' pneumoconiosis (CWP) and a plethora of other hazards in both underground and open cast mines on a daily basis. The aim of the study is to assess the knowledge, attitude and practice of coal mineworkers pertaining to occupational health and safety at the Leeuwpan mine in Mpumalanga province of South Africa. The study adopted a quantitative, cross sectional descriptive design. Self-reported questionnaires with closed-ended questions were administered to the eligible participants. The study targeted the 3200 coal mineworkers who were employed at the Leeuwpan mine in Lephalale. A sample of 356 mineworkers was used as derived from Slovin’s formula and data was collected over a period of 5 days at the Leeuwpan mine. Measures to ensure validity and reliability were ensured and ethical considerations were observed. The Statistical Package for Social Sciences (SPSS) version 23.0 was used to analyse the data. Results and recommendations are based on the findings of the study. / NRF
144

Geochemical and mineralogical characterization of gold mine tailings for the potential of acid mine drainage in the Sabie - Pilgrims's Rest Goldfields

Lusunzi, Rudzani 21 September 2018 (has links)
MESMEG / Department of Mining and Environmental Geology / This study entails geochemical and mineralogical characterization of gold tailings of Nestor Mine and Glynn’s Lydenberg Mine of the Sabie-Pilgrim’s Rest goldfields. A total of 35 samples were collected and were analysed for chemical composition (XRF and ICP-MS), mineralogical composition (XRD). In addition, acid-base accounting (ABA) techniques had been conducted to predict the potential for acid mine drainage. Seepage from Nestor tailings dump and water samples from the adjacent Sabie River were also collected and analysed by means of inductively coupled plasma mass spectrometry (ICP-MS) and immediate constituent (IC) -analytical techniques. The study revealed that Sabie-pilgrim’s rest goldfield is characterized by both acid generating and non-acid producing tailings, and this is attributed to variations in the mineralogy of source rocks. Gold occurred within the Black Reef Quartzite Formation in the Nestor Mine and within the Malmani Dolomite in the case of Glynn’s Lydenburg Mine. Mineralogy and bulk geochemical analyses performed in this study showed a clear variation in the chemistry of Nestor Mine and Glynn’s Lydenburg Mine tailings. Predominant oxides in Nestor mine tailings samples are SiO2 (ranging from 66.7-91.25 wt. %; followed by Fe2O3 and Al2O3 (in range of 0.82-15.63 wt. %; 3.21-12.50 wt. % respectively); TiO2 (0.18-10.18 wt. %) and CaO (0.005-3.2 wt. %). Also occurring in small amounts is CaO (0.005-3.2 wt. %), K2O (0.51-2.27 wt. %), MgO (0.005-1.46 wt. %), P2O5 (0.029-0.248), Cr2O3 (0.013-0.042 wt. %) and Na2O (0.005-0.05 wt. %). The samples also contain significant concentrations of As (137-1599 ppm), Cu (34-571 ppm), Cr (43-273 ppm), Pb (12-276 ppm), Ni (16-157 ppm), V (29-255 ppm), and Zn 7-485 ppm). In the Glynn’s Lydenburg Mine tailings SiO2 is also the most dominant oxide ranging between 47.95 and 65.89 w%; followed by Al2O3 (4.31 to 16.19 wt. %), Fe2O3 (8.48 to 11.70 wt %), CaO (2.18 to 7.10 wt. %), MgO (2.74 to 4.7 wt. %). Occurring in small amounts is K2O (1.12-1.70 wt. %), MnO (0.089-0.175 wt. %), P2O5 (0.058-0.144 wt. %) and Cr2O3 (0.015-0.027 wt. %). Arsenic (As), is also occurring in significant amounts (807-2502 ppm), followed by Cr (117-238 ppm), Cu (10-104 ppm), V (56-235 ppm), Ni (45-132 ppm), Pb (13-63 ppm) and Zn (90-240 ppm). Nestor Mine tailings associated with Black Reef Formation mineralization have net neutralizing potential (NPR) <2, hence more likely to generate acid; and their acid potential (AP) ranges 1.56 to 140.31 CaCO3/ton and neutralizing potential (NP) range from -57.75 to -0.3 CaCO3/ton. Glynn’s Lydenburg Mine tailings dump which is vi associated with dolomite mineralization, however, was not leaching acid. Based on acid-base accounting results, these tailings have more neutralizing potential (ranging between 57.6 and 207.88 CaCO3/ton) than acid potential (ranging between 7.5 and 72.1 CaCO3/ton); and their NPR>2, hence unlikely to produce acid. This is confirmed by paste pH which was in the ranges between 7.35 and 8.17. Tailings eroded from Nestor Mine tailings dump were also found to be characterized by high content of metals and oxides, namely, As, Cu, Ni, Pb, V, and Zn with SiO2, Fe2O3 and TiO2. The tailings were observed eroded into the Sabie River where AMD related precipitate (yellow boy) was also observed, indicating further oxidation downstream. Field observations, onsite analyses of water samples and laboratory results revealed that Nestor Mine tailings storage facility discharges acid mine drainage with considerable amounts of Al, As, Cu, Fe, Mn, Zn and SO4 and very low pH exceeding the limit as per South African water quality standards. High concentrations of these metals have toxicity potential on plants, animals and humans. Upon exposure to oxygen and water, tailings from Nestor Mine are more likely to generate acid mine drainage that can cause detrimental effect to the environment and the surrounding communities. Potential pollutants are Fe, Mn, Al, As, Cr, Cu, Ni and Pb. Tailings from Glynn’s Lydenberg showed no potential for acid mine drainage formation. / NRF
145

Green synthesis of geopolymeric materials using Musina Copper Mine Tailings: a case of beneficial management of mine tailings

Matidza, Murendeni 17 September 2019 (has links)
MENVSC / Department of Ecology and Resource Management / Mine tailings (MT) have been a global problem due to the environmental impacts the waste generates such as air, soil and water pollution. The detrimental impacts include a global problem such as acid mine drainage (AMD) which has been difficult to cleanup. Several studies have been conducted to find alternative measures in reducing or mitigating impacts such as AMD and air pollution. Several studies have revealed how alumino-silicate mineral waste can be used as raw material to produce construction materials. This study aimed at evaluating the potential of synthesizing a geopolymer material from Musina copper mine tailings. Tailings were characterized for their physicochemical and mineralogical compositions using standard laboratory techniques in order to evaluate suitability in geopolymerization. First section of the results presented physicochemical and mineralogical characterization of the Musina copper tailings together with the bioavailability of the chemical species. It was observed that the tailings are mainly composed of SiO2 and Al2O3 as the major oxides indicating that they are aluminosilicate material. Mineralogical analysis revealed dominance of quartz, epidote and chlorite as the major minerals. The bioavailability assessment showed that largely Cu and Ca are bioavailable and highly soluble in an aqueous solution while Al, Mg, Ni, Co, Cr and Fe have a high proportion in non-labile phase. Second section presented the preliminary results wherein the potential application of Musina copper tailings in geopolymerization was evaluated. The results showed that Musina copper tailings can be used to synthesize a geopolymer material. However, it was recommended that several parameters influencing geopolymerization need to be evaluated. The third section presented the evaluation of optimum parameters that influence the geopolymerization process, which include type of alkali activators, alkali activator concentration, curing temperature, liquid-solid (L/S) ratio and curing regime. It was observed that a mixture of NaOH:Na2SiO3.5H20 at a ratio of 70:30 yields a better geopolymer material. The concentration of 10 M NaOH:Na2SiO3.5H20 at a ratio of 70:30 was observed to be the best that yielded the UCS that is acceptable according to SANS1215 standards. When evaluating curing regime, it was found that the material cured using greenhouse has lower UCS as compared to the material cured using oven. The v effect of temperature showed that the UCS decreases with increasing curing temperature. An admixture of river sand and cement was introduced which resulted in a high UCS of 21.16 MPa when using an admixture of cement. The mineralogical composition of the geopolymer bricks showed formation of secondary minerals such as phlogopite, fluorapatite, diopside and actinolite. Batch leaching conducted on the geopolymer bricks detected high leaching of Na from the bricks. Based on the findings of the study of the raw MT potential to produce geopolymer bricks, it was concluded that the material can be used to produce bricks that are within the SANS 1215 requirements. The study further recommended that the study a focus on using cylindrical moulds, other alkali activators and a mechanical mixer. It was also recommended that the greenhouse be restructured to contain heat within the greenhouse during the evening so as to allow constant temperature within / NRF
146

An evaluation of the ecological impacts of sand mining on the Mokolo River in Lephalale, South Africa

Maeko, Mokgadi Precious 11 1900 (has links)
This study aimed to evaluate the ecological impacts of sand mining on the Mokolo River, in Lephalale. The study focused on the water quality, macroinvertebrates and physical disturbances as indicators in order to determine the ecological im-pacts of sand mining on the Mokolo River. The water quality variables, which this study entailed, were related to sand mining and other sources of pollution such as coal mining, power station industries, agriculture and wastewater treatment works on the Mokolo River. The water quality results for pH, electrical conductivity (EC), total alkalinity (CaCO3), sodium (Na), calcium (Ca), magnesium (Mg), potassium (K), chloride (Cl), fluoride (F), sulphate (SO4) and nitrate (NO3-N) were not over the limits, however turbidity, total coliforms and E. coli were over the limits as per the Target Water Quality Guideline (TWQG). The River Health Programme (RHP) was done at upstream, sand mining and downstream areas in the Mokolo River using the South African Scoring System Version 5 (SASS5). The ecological status at the upstream and downstream areas changed from class C (March 2018) to class B (November 2018), indicating that the ecological status improved in those areas of the Mokolo River. However, at the sand mining area the ecological status has not improved and it was seriously modified due to the physical disturbance as a result of sand mining. Ecological impacts, such as the removal of marginal and riparian vegetation, erosion, disturbed riverbed, undercutting and collapse of riverbanks, loss of adjacent land, river deepened, river widened, water pools, in stream sand stockpiles and river diversions, were determined at the sand mining area. No physical disturbances at the upstream and downstream areas were determined. The findings of this study indicate that the ecological impacts of change in water quality at the upstream and downstream areas was due to high turbidity, Total coli-forms and E. coli. The absence of sensitive macroinvertebrates and loss of ma-croinvertebrates and the physical disturbances within the Mokolo River was be-cause of sand mining. The study indicates that sand mining has negative impacts on the water quality, water quantity, macroinvertebrates and physical characteris-tics of the Mokolo River. / Environmental Sciences / M. Sc. (Environmental Science)
147

The rebellious and ungovernable Barberton community against Barberton Mines (Pty) Ltd

Ngomane, Fortunate Nomxolisi 01 1900 (has links)
Text in English / This is a study of community protest against Barberton Mines (Pty) Ltd. It is a study of conflict and conflict resolutions. Barberton Mines (Pty) Ltd is one of the three gold mining companies in Barberton, and is in dire need of a bankable community/stakeholder relation management strategy, which should at least reduce, if not eliminate, the endless violent community protests against its operations. Methodologically, the study is predicated on a qualitative approach backed by oral interviews and the use of a survey. The study reveals that as much as the community appreciates Barberton Mines for its delivery in socio-economic development initiatives, Barberton Mines’ recruitment and procurement departments are not doing any justice in terms of preferred policy in favour of the locals/Barberton community. This is a key source of conflict. The results also reveal that the Barberton Mines Transformation Trust (BMTT), a vehicle established for socioeconomic development in Barberton, is considered to be ineffective by the community and is one of the causes of the conflict. The resolutions of the conflict include the effective implementation of the mining legislation and unrolling of the Mining Charter. The effectiveness and lack thereof of these conflict resolutions are subjected to analysis in this study. / Development Studies / M.A. (Development Studies)
148

A security risk management approach to the prevention of theft of platinum group metals: case study of Impala Platinum Mines and Refinery

Mokhuane, Seadimo Joseph 02 1900 (has links)
Text in English / The purpose of this study was to establish the vulnerabilities of the security control measures that are being used at Impala Platinum mines and refinery to prevent the theft of Platinum Group Metals (PGMs). It is important to ensure that the security control measures in place are effective and efficient in preventing the occurrence of such theft. The research examined the security risk management approach to the prevention of theft of PGMs and the causes of theft of PGMs by organised crime syndicates operating in South Africa and abroad. The study found that Impala Platinum employees, in collusion with contractors and members of mine security services, are involved in the theft of PGMs. To achieve the goals and objective of the research study, effective security control measures were identified that will help Impala Platinum mines and refinery to overcome the risks and challenges related to the theft of PGMs. / Security Risk Management / M. Tech. (Security Management)
149

Development of product quality management guidelines for informal small-scale brick manufacturing enterprises in Dididi, Limpopo Province, South Africa

Matsiketa, Khensani Eullen 18 May 2018 (has links)
MESMEG / Department of Mining and Environmental Geology / Although clay brick manufacturing has been going on for many years in South Africa, informal small-scale clay brick manufacturing enterprises are not officially regulated. Consequently, informal brick makers in the study area do not adhere to the demanding requirements of the South African National Standards for burnt clay masonry. Therefore, their clay bricks lack uniformity in terms of quality. Preliminary work revealed that over time, buildings constructed with these bricks develop cracks, thereby compromising safety. The importance of product quality management is not well understood in the informal brick manufacturing enterprises. As a result, they do not have any product quality management guidelines. The main purpose of this research was to develop the product quality management guidelines for ensuring quality in small-scale brick making enterprises in Dididi area. The specific objectives were to characterize the raw materials for clay brick manufacturing, identify and assess the technical problems of clay brick production, analyse the process of clay brick production and determine areas where product quality improvement is warranted. The research involved fieldwork which included soil sampling, analysis of clay brick production through the use of questionnaires and onsite observation of the production process, collection of samples of burnt bricks which were examined for compressive strength, water absorption as well as dimension measurements. These were then compared with the prescribed quality standards. Laboratory analyses of samples of raw materials were conducted and these included sieve analysis which was conducted in order to establish the particle size distribution of the raw materials; Atterberg limit tests were conducted in order to establish the physical characteristics of the soil. Chemical and mineralogical analyses were carried out to determine the chemical and mineralogical composition of the soil using XRF and XRD respectively. The textural characterisation of the material revealed abundance of sand sized particles and significantly low amounts of clay and silt. The plasticity of the soil used for bricks manufacturing in the study area was found to be ranging from slight to medium plasticity. Chemical analysis showed elevated silica contents with minor amounts of alumina and iron oxide. XRD analysis revealed the dominance of non-clay minerals with the highest concentration of quartz. The average compressive strengths of the tested brick samples for site A was 3.8, and 2.9 and 3.8 MPa for sites B and C respectively. The water absorption of the bricks was 13.5, 15.0 and 16.1% for samples from Site A, B and C respectively. The bricks dimensions met the recommended standards although their sizes were not uniform. v The survey conducted on brick manufacturing process revealed that the technical inefficiencies were mostly influenced by human and mechanical factors as well as the material inappropriateness. The production process was found to be too manual and labour intensive. Selection of the raw materials for brick manufacturing was based on indigenous knowledge and experience and most of the brick manufacturers lacked the prerequisite experience for making quality bricks. On the basis of the results of this research, it can be concluded that the materials used for manufacturing of clay bricks in Dididi are not well suited for making good quality bricks due to the reduced plasticity of the soil and the high concentration of quartz. These render the bricks brittle. It was also concluded that the production process also contributes to the poor quality of the bricks as the nature of the process was too manual. Selection of materials based merely on knowledge and experience and no scientific tests resulted in selection of inadequate materials which in turn affect the quality of the final bricks. It is therefore recommended that plastic clays be added to the raw clay materials to enhance its moulding property. In addition, materials such as internal fuels and anti-shrinkage materials should be incorporated into the process cycle to prevent cracking during drying and firing. Based on the findings of the analysis of the production process, it is recommended that mechanized techniques be employed in the operation and awareness training conducted to improve the understanding and skills of the brick manufacturers and to ensure production of good quality bricks. / NRF
150

A critical evaluation of local level responses to mine closure in the Northwestern KwaZulu-Natal coal belt region, South Africa

Buthelezi, Mbekezeli Simphiwe January 2004 (has links)
The de-industrialisation process that was a common feature of North America and Western Europe in the 1970s, through into the 1980s has become an observable feature in African countries and South Africa in particular in the last two decades. Globally, hard hit areas include those associated with the early Industrial Revolution characterised by mass production and the agglomeration of iron and steel, coal and textile industries. General changes in the global market, especially the falling demand for extractive heavy minerals like coal and gold have also affected many countries region and localities. In the case of South Mrica, the previous high economic dependence on mined minerals like coal and gold has resulted in many once prosperous mining regions of the country being reduced to a shadow of their former selves. The worst affected areas in South Africa are those of the Klerksdorp Goldfields in the North West Province and Free State Goldfields, with the latter alone losing 100,000 jobs during the 1990s. This trend has also been acute in the coal-mining industry of the KwaZulu-Natal province since the late 1970s. The firms that had grown in the shadow of the major mining company supplyipg machinery, or who processed the semi-manufactured product are also severely affected by the closing down and restructuring in the mining and iron industries. These industries have often been forced to close down because of a break in the vital connections they developed with these mining industries. Such localised economic crisis has encouraged the universal trend towards the devolution of developmental responsibilities to the local governments and other local stakeholders to - empower them to respond to these changes. This study investigated the local economic initiatives which have been undertaken in the three municipalities of north-western KwaZulu Natal i.e. Utrecht, Dundee and Dannhauser to respond to the closures which have taken place in the mining industry of this region, which used to be among the most prosperous coal mining regions of South Africa. Using their new developmental mandate the local governments, in partnership with the communities and other external interveners have tried to respond to these localised economic crisis and also indirectly to the general poverty and underdevelopment, which characterises this region of KwaZulu-Natal. The effects of apartheid policies, and previous discriminatory rural development policies in, particular, and the Regional Industrial Development policy, which was intensively applied in the 1980s by the pre-1994 government regime, have further compounded the magnitude of the challenge. The lack of capacity in some municipalities has constrained successful implementation of Local Economic Development has led to some communities acting alone to face their situation with or without external intervention.

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