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1
Anderson, Jonathan D. "Impacts of amending bauxite residue sands with residue fines for the establishment of vegetation on residue disposal areas /". Murdoch University Digital Theses Program, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.
Testo completo
2
Kopittke, Peter Martin. "Limitations to plant root growth in highly saline and alkaline bauxite residue /". [St. Lucia, Qld.], 2004. http://adt.library.uq.edu.au/public/adt-QU20040913.094109/index.html.
Testo completo
3
Mengler, Faron. "Gully erosion on rehabilitated bauxite mines". University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0176.
Testo completoAbstract (sommario):
[Truncated abstract] Landforms rehabilitated after bauxite mining can be vulnerable to soil loss by water erosion processes. On most rehabilitated sites, management controls such as deep ripping, contour mounding and landscaped sub-catchments limit erosion. Despite these measures, severe gully erosion that is anecdotally associated with steep slopes can damage rehabilitated areas and affect downstream drinking water resources. A review of erosion dynamics reveals that gullies develop episodically and in a non-linear manner. They often initiated as a near surface process and are influenced by natural climatic drivers. Despite this, local site characteristics including soil and landform can predispose an area to gully erosion. Moreover, erosion models, becoming more-widely utilized within the mining industry, may provide useful tools with which to measure, analyse, and manage gully erosion. One of these models, SIBERIA was tested to determine its suitability for application a tool to help manage erosion risk. We first surveyed 26 eroding and erosion-prone rehabilitated hillslopes to determine the common form and setting for gully erosion on these rehabilitated bauxite mines. A conceptual model was developed to include and explore the interplay between the common causes of the gullies surveyed. The conceptual model accounts for slope steepness but suggests that additionally, certain triggers and threshold effects operating under different site conditions are as influential (or even more influential) than slope steepness as determinants of gully erosion occurrence and severity. ... Soil properties and soil erodibility had some subtle influence on landform stability and erosion risk. The most-erodible media occurred where either: mine floor material was mixed with topsoil/ overburden; and/or the topsoil/overburden layer was thin or its coverage is patchy resulting in slaking subsoil, hardsetting soil and surface crusts. When erodible surface media were combined with steeper (>8[degrees]) or longer (>50 m) slopes or with any major erosion trigger, rill and gully development was greatly intensified. The SIBERIA simulation model was calibrated and its simulated outputs were compared to known locations of gully erosion on a steep, rehabilitated pit from the Willowdale mine. At a resolution of one metre, SIBERIA was able to simulate the approximate dimensions of gullies. However, SIBERIA could not simulate the exact location of individual gully headcuts. Additionally, SIBERA was able to simulate the effect of different microtopographic surface treatments but this was only achieved by increasing the grid resolution to 25 cm and reducing the size of the area simulated due to model constraints. Locations of gully headcuts were overlain onto a grid-based, Digital Elevation Model (DEM) using a Geographic Information System (GIS). The spatial distribution of gully headcut locations was compared to DEM derivatives such as slope and flow accumulation. Positive, and predictive relationships allow between the steepness of the slope of the pre-mining landform and the cell count of the area contributing to flow (catchment), as determined by GIS, may allow a mine scale indication of erosion risk using simple GIS desktop analysis.
4
Dias, Fabiana Ferrari. "Percepção da população em relação as empresas de lavra e beneficiamento de Bauxita no municipio de Poços de Caldas, MG". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287123.
Testo completoAbstract (sommario):
Orientador: Rachel Negrão CavalcantiTese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias
Made available in DSpace on 2018-08-09T15:11:01Z (GMT). No. of bitstreams: 1 Dias_FabianaFerrari_D.pdf: 11281113 bytes, checksum: 92b77a510956fc2cc26128258cf02bf2 (MD5) Previous issue date: 2007
Resumo: Intensas atividades de mineração na região de Poços de Caldas se tornaram o objeto de sérias discussões. O alumínio é extraído da bauxita encontrada em áreas próximas à malha urbana. A população está ciente de tais atividades de mineração, entretanto, não há um claro entendimento sobre impactos sociais e ambientais. Questionários cuidadosamente preparados foram submetidos aos representantes da população, aos membros voluntários das ONGs locais e aos governantes pertinentes. Bancos de dados federais foram utilizados para reunir informações sobre áreas locais de concessões de mineração. Resultados georeferenciados indicaram que a população possui uma percepção positiva sobre as atividades de mineração e está ciente da sua importância. Entretanto, o estudo foi capaz de identificar algumas deficiências nas estratégias de comunicação empregadas pelas empresas de mineração. Esta Tese é uma fonte de dados para a percepção da população em relação às atividades de mineração e foi empregada para criar um banco de dados GIS. Em adição, apontou estratégias modernas que podem ajudar a melhorar o relacionamento entre as empresas de mineração e a população local e direcionar outros projetos similares envolvendo variadas atividades de mineração próximas às áreas urbanas
Abstract: Intense mining activities in the region of Poços de Caldas have become the object of serious discussion. Aluminum is extracted from bauxite ore found in areas near urban developments. The population is aware of such mining activities, however, there is no clear understanding regarding social and environmental impacts. Carefully prepared questionnaires were submitted to representatives from the general population, to volunteer members of local NGOs, and government authorities. Available government databases were employed to gather information about local mining concession areas. Georeferenced results indicated that the population perception towards mining activities is positive and the population is aware of its importance. However, the study was able to identify some deficiencies in communication strategies employed by the mining companies. This thesis is a source of data for population perception regarding mining activities and was employed to create a GIS database. In addition, it pointed out modern strategies that can help to improve the relation between mining companies and the local population and guide other similar projects involving diverse mining activities near urban areas
Doutorado
Administração e Politica de Recursos Minerais
Doutor em Ciências
5
Prananto, Agnes Kristina. "The use of remotely sensed data to analyse spatial and temporal trends in vegetation patchiness within rehabilitated bauxite mines in the Darling Range, W.A. /". Connect to this title, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0012.
Testo completo
6
Collins, Margaret Thora. "Factors affecting the recovery of orchids in a post-mining landscape". University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0022.
Testo completoAbstract (sommario):
[Truncated abstract] Currently, Alcoa World Alumina Australia (Alcoa) mines and undertakes procedures to rehabilitate approximately 550 ha of jarrah forest each year at two open-cut bauxite mines in South-West Western Australia. Alcoa aims to establish a self-sustaining jarrah forest ecosystem that maintains the functions of the landscape prior to mining, including biodiversity, on areas that have been mined for bauxite. Indigenous terrestrial orchids form a significant proportion of the indigenous geophytic plant species that either fail to colonise rehabilitated areas or do so very slowly. Terrestrial orchids are considered to be particularly sensitive to competition from weeds and disturbance, which combined with the obligate nature of the orchid-mycorrhizal fungus association suggests that orchids would colonise rehabilitation areas only when both microhabitat sites and soil microflora have established. Occurrence of certain orchids may therefore be expected to be useful as indicators of ecosystem health, the success of vegetation establishment and the recovery of edaphic conditions suitable for orchid mycorrhizal fungi. Vegetation surveys were undertaken to compare orchid species richness and population size of a chrono-sequence of rehabilitation areas with adjacent unmined forest. ... Orchid taxa present in each vegetation assemblage were generally not exclusive to these assemblages, with the following broad exclusions: D. bracteata was found only in species assemblages associated with rehabilitation areas; and Eriochilus sp. and T. crinita were found only in species assemblages associated with unmined forest. No single orchid species appears to be an indicator of ecosystem recovery. However, the presence of populations of C. flava, P. sp. crinkled leaf (G.J.Keighery 13426) or P. recurva in combination with the absence of the disturbance opportunist orchid taxa D. bracteata and M. media appears to be a measure of the maturity of the rehabilitation vegetation. Orchid species richness and clonal orchid population size were correlated with changes in vegetation structure, but apart from the absence of orchids in 1 year old rehabilitation areas, these orchid population characteristics did not show any direct relationship with rehabilitation age or vegetation maturity. Only two orchid taxa appeared to have potential as indicators of vegetation characteristics: T. crinita as an indicator of undisturbed jarrah forest; and D. bracteata as an indicator of disturbed ecosystems. The results of this study suggest that most jarrah forest orchid taxa will readily colonise the post bauxite mining landscape, but that the unassisted colonisation by recalcitrant orchid taxa may be a prolonged process. It is recommended that field-based transplantation and/or seeding trials be undertaken with these recalcitrant taxa to determine if these procedures will enhance recruitment. The results of this work have applications not only in the management of post-mining landscapes but also in vegetation monitoring and conservation work in Western Australia and elsewhere.
7
Hellyer, William N. "Assessment of Benthic Macroinvertebrate Community Impairment from High-Aluminum Acid Mine Drainage in Middleton Run, Ohio, USA and the Impact of Ingested Aluminum on Crayfish Growth". Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1399465953.
Testo completo
8
Bleby, Timothy Michael. "Water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on mine rehabilitation sites in the jarrah forest of south-western Australia". University of Western Australia. School of Plant Biology, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0004.
Testo completoAbstract (sommario):
[Truncated abstract. Please see the pdf format for the complete text. Also, formulae and special characters can only be approximated here. Please see the pdf version for an accurate reproduction.] This thesis examines the water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on bauxite mine rehabilitation sites in the jarrah forest of south-western Australia. The principal objective was to characterise the key environment and plant-based influences on tree water use, and to better understand the dynamics of water use over a range of spatial and temporal scales in this drought-prone ecosystem. A novel sap flow measurement system (based on the use of the heat pulse method) was developed so that a large number of trees could be monitored concurrently in the field. A validation experiment using potted jarrah saplings showed that rates of sap flow (transpiration) obtained using this system agreed with those obtained gravimetrically. Notably, diurnal patterns of transpiration were measured accurately and with precision using the newly developed heat ratio method. Field studies showed that water stress and water use by jarrah saplings on rehabilitation sites were strongly seasonal: being greatest in summer when it was warm and dry, and least in winter when it was cool and wet. At different times, water use was influenced by soil water availability, vapour pressure deficit (VPD) and plant hydraulic conductance. In some areas, there was evidence of a rapid decline in transpiration in response to dry soil conditions. At the end of summer, most saplings on rehabilitation sites were not water stressed, whereas water status in the forest was poor for small saplings but improved with increasing size. It has been recognised that mature jarrah trees avoid drought by having deep root systems, however, it appears that saplings on rehabilitation sites may have not yet developed functional deep roots, and as such, they may be heavily reliant on moisture stored in surface soil horizons. Simple predictive models of tree water use revealed that stand water use was 74 % of annual rainfall at a high density (leaf area index, LAI = 3.1), high rainfall (1200 mm yr-1) site, and 12 % of rainfall at a low density (LAI = 0.4), low rainfall (600 mm yr-1) site, and that water use increased with stand growth. A controlled field experiment confirmed that: (1) sapling transpiration was restricted as root-zone water availability declined, irrespective of VPD; (2) transpiration was correlated with VPD when water was abundant; and (3) transpiration was limited by soil-to-leaf hydraulic conductance when water was abundant and VPD was high (> 2 kPa). Specifically, transpiration was regulated by stomatal conductance. Large stomatal apertures could sustain high transpiration rates, but stomata were sensitive to hydraulic perturbations caused by soil water deficits and/or high evaporative demand. No other physiological mechanisms conferred immediate resistance to drought. Empirical observations were agreeably linked with a current theory suggesting that stomata regulate transpiration and plant water potential in order to prevent hydraulic dysfunction following a reduction in soil-to-leaf hydraulic conductance. Moreover, it was clear that plant hydraulic capacity determined the pattern and extent of stomatal regulation. Differences in hydraulic capacity across a gradient in water availability were a reflection of differences in root-to-leaf hydraulic conductance, and were possibly related to differences in xylem structure. Saplings on rehabilitation sites had greater hydraulic conductance (by 50 %) and greater leaf-specific rates of transpiration at the high rainfall site (1.5 kg m-2 day1) than at the low rainfall site (0.8 kg m-2 day1) under near optimal conditions. Also, rehabilitation-grown saplings had significantly greater leaf area, leaf area to sapwood area ratios and hydraulic conductance (by 30-50 %) compared to forest-grown saplings, a strong indication that soils in rehabilitation sites contained more water than soils in the forest. Results suggested that: (1) the hydraulic structure and function of saplings growing under the same climatic conditions was determined by soil water availability; (2) drought reduced stomatal conductance and transpiration by reducing whole-tree hydraulic conductance; and (3) saplings growing on open rehabilitation sites utilised more abundant water, light and nutrients than saplings growing in the forest understorey. These findings support a paradigm that trees evolve hydraulic equipment and physiological characteristics suited to the most efficient use of water from a particular spatial and temporal niche in the soil environment.
9
Lalor, Briony Maree. "An assessment of the recovery of the microbial community in jarrah forest soils after bauxite mining and prescription burning". University of Western Australia. School of Earth and Geographical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0037.
Testo completoAbstract (sommario):
[Truncated abstract] Recovery of soil nutrients, microbial populations and carbon (C) and nitrogen (N) cycling processes are critical to the success of rehabilitation following major ecosystem disturbance. Bauxite mining represents a major ecosystem disturbance to the jarrah (Eucalyptus marginata) forest in the south-west of Western Australia. Mining has created a mosaic of mined areas in various stages of succession surrounded by non-mined forest areas. Initial site preparations within rehabilitation areas such as contour ripping alter soil structure (creation of mound and furrows) and over time also influence the distribution of vegetation and litter. Current performance criteria developed by industry, government and other stakeholders have determined that before post-bauxite mined areas of jarrah forest can be integrated back into normal forest management practises they should be functional and demonstrate resilience to normal forest disturbances such as fire. Furthermore, resilience should be of a manner comparable to non-mined analogue forest sites. Currently little is known of the resilience of microbial communities and C and N cycling in rehabilitation sites to normal forest disturbances such as prescription burning. As such, before rehabilitated jarrah forests can be successfully integrated into broad scale forest management regimes, a more thorough knowledge of the potential impacts of burning practises on the soil microbial community and C and N cycling processes in these systems is required. ... While there are similar rates of C and N cycling the underlying microbial community structure was distinctly different; implying a high degree of functional redundancy with respect to C and N cycling. Differences in the C and N cycling and structure of the microbial communities were likely to be due to differences in soil environmental conditions (i.e. soil alkalinity/acidity, soil moisture) and C substrate availability which influence the physiological status of the microbial community and in turn are related to successional age of the forests. Results also suggest that the measurement of CLPP can be a useful approach for assessment of changes in the functional ability of microbial communities. However, the interpretation of how well these rehabilitation forests have recovered heterotrophic abilities was greatly affected by the methodological approach used (e.g. MicroRespTM or Degens and Harris, 1997). Importantly, results from Chapter 4 and 5 suggested that the effects of a moderate prescription fire on C and N processes, CLPP and microbial community structure of 18 year old rehabilitation forests are likely to be short-lived (< 2 years). Furthermore, the effects of the moderate spring prescription fire were not large enough to decouple C and N cycling processes over the short-term (< 1 years) which suggests that by 18 years of age rehabilitation forests demonstrate comparable functional resilience to a moderate prescription burn.
10
Prananto, Agnes Kristina. "The use of remotely sensed data to analyse spatial and temporal trends in vegetation patchiness within rehabilitated bauxite mines in the Darling Range, W.A". University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0012.
Testo completoAbstract (sommario):
[Truncated abstract] The assessment of rehabilitation success is time consuming and costly for bauxite miners because large areas of land (~550 ha per year) are involved. In some cases, rehabilitation results in patches of bare or sparsely vegetated soil. This study uses remote sensing imagery to evaluate the growth of vegetation in rehabilitated bauxite mines in the Darling Range, W.A. This work has five aims, which are to (1) compare vegetation biomass within rehabilitated areas and nearby native forest; (2) analyse temporal changes in vegetation growth within the selected rehabilitated areas, in particular rehabilitated areas with patches of bare soil; (3) compare vegetation growth pre- and post- mining; (4) identify the best type of remotely sensed data for this particular study area, and (5) develop an index, which can classify the degree of vegetation patchiness within rehabilitated mine sites. This information will enable rehabilitation workers to identify patches in rehabilitated areas that may require further remediation. The study used RADARSAT, nine years of Normalised Difference Vegetation Index (NDVI) maps (extracted from LANDSAT TM multivariate imagery and Quickbird imagery) and aerial photographs to evaluate forty-seven ~1 ha study sites. Image and map analyses were conducted mainly using ESRI’s software ArcGIS 8.3 and ER Mapper 6.4. Ground truthing was carried out to confirm and recognise the causes of bare patches within the rehabilitated mine sites ... The results indicate that differences in rehabilitation management do not affect this index but the extent of bare patches does. Due to the sensitivity of radar imagery to surface roughness, rehabilitated areas cannot be distinguished from the native forest using radar images. A building (crusher) appears to be the same as mature vegetation. Knowledge of the features in an area is therefore crucial when utilising RADARSAT. The beam elevation angle and profile of the RADARSAT image used, made superimposition of radar and optical imageries impossible. Speckle noise in RADARSAT images made it impossible to detect relatively small bare patches. In addition, the many cloud free days in Western Australia make optical imaging possible so that the ability of radar imagery to penetrate cloud is redundant for this type of study.
11
Szota, Christopher. "Root morphology, photosynthesis, water relations and development of jarrah (Eucalyptus marginata) in response to soil constraints at restores bauxite mines in south-western Australia". University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0058.
Testo completoAbstract (sommario):
Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots. Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots.
12
Wang, Quanxi. "Integrated stability mapping system for mines". Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4287.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains ix, 145 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 118-122).
13
Talhi, Korichi. "Aspects of blasting in surface mines". Thesis, University of Surrey, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280422.
Testo completo
14
Joubert, Barend Daniel. "Small-scale gold mining in southern Africa". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005615.
Testo completoAbstract (sommario):
The general characteristics of gold deposits are reviewed, and a classification of gold deposits based on mineability is proposed. Evaluation, mlnlng and beneficiation methods are briefly discussed. It is concluded that the most viable targets for small-scale companies comprise deposits that require the least pre-production time and expense. Great potential exists for the small-scale reclamation of gold from tailings dumps and abandoned mines in Southern Africa. There is also potential for developing new smallscale gold mines in the Archaean greenstone terranes of the Zimbabwean and Kaapvaal cratons.
15
Forrest, W. "The development of new coal mines". Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378766.
Testo completo
16
Carr, Frank. "Government decision-making and environmental degradation: a study relating to mining activities in Papua New Guinea". Thesis, Carr, Frank (2007) Government decision-making and environmental degradation: a study relating to mining activities in Papua New Guinea. Masters by Research thesis, Murdoch University, 2007. https://researchrepository.murdoch.edu.au/id/eprint/502/.
Testo completoAbstract (sommario):
Papua New Guinea (PNG) is a country possessing abundant resources of gold, oil, copper, timber, and fish stocks. It is hampered in its development and management of these resources, however, by serious problems of governance and corruption. These problems are evident throughout the economy and also in the management of the environment. The level of environmental damage caused by the mining industry in PNG is now such that it will require extensive rehabilitation, if the areas affected can, indeed, ever be fully rehabilitated. The mining companies which precipitated this damage were licensed and encouraged by the PNG Government in the initiation and exercise of the mining operations. The resulting environmental impact has affected the lives of thousands of New Guineans to their detriment. The degradation caused remains
unredressed.
Compounding the problem, there is a growing reliance by Papua New Guinea on mineral exploitation for foreign direct investment, government revenues, and foreign exchange. Gold exports accounted for the biggest share of export revenues in 2002 representing 37.5% of the total. In light of this growing dependency on mining activities, there is a correspondingly urgent requirement to address the deficiencies in the administrative, monitoring, and policing aspects of the protection of its environment.
Despite the public evidence of the damage to the environment and the ensuing affect on the people of Papua New Guinea by mining activities; and despite universal condemnation of these activities and the companies responsible; the companies continue to conduct these activities without official hindrance and with little apparent concern for the long-term ramifications of their actions.
This thesis will examine the degradation resulting from the mining activities of companies in Papua New Guinea over the last three decades - particularly those of Placer Dome's Porgera gold mine, BHP's Ok Tedi gold and copper mine (the waste from both of which is dumped into the Ok Tedi and Strickland rivers which are tributaries of the Fly River and form part of the Fly River system) and Lihir Gold Limited's gold mine on Lihir Island. It will examine the extent to which the Government of Papua New Guinea may have wittingly (in the sense of a prescience as to the possible or probable likelihood of deleterious impact) or unwittingly contributed to that degradation as a result of its actions or omissions.
Studies of available literature suggest that there has been little attention paid to the subject of culpability on the part of successive PNG governments in matters of environmental damage. This research will contribute to reducing this gap in the literature by focusing on possible motives of the PNG government and its actors which precipitated those decisions and which resulted in environmental degradation. The discussion will examine the likely motivation of the PNG government in its deliberations and decisions and the extent to which corruption and incompetence may have played a role.
17
Carr, Frank. "Government decision-making and environmental degradation : a study relating to mining activities in Papua New Guinea /". Carr, Frank (2007) Government decision-making and environmental degradation: a study relating to mining activities in Papua New Guinea. Masters by Research thesis, Murdoch University, 2007. http://researchrepository.murdoch.edu.au/502/.
Testo completoAbstract (sommario):
Papua New Guinea (PNG) is a country possessing abundant resources of gold, oil, copper, timber, and fish stocks. It is hampered in its development and management of these resources, however, by serious problems of governance and corruption. These problems are evident throughout the economy and also in the management of the environment. The level of environmental damage caused by the mining industry in PNG is now such that it will require extensive rehabilitation, if the areas affected can, indeed, ever be fully rehabilitated. The mining companies which precipitated this damage were licensed and encouraged by the PNG Government in the initiation and exercise of the mining operations. The resulting environmental impact has affected the lives of thousands of New Guineans to their detriment. The degradation caused remains
unredressed.
Compounding the problem, there is a growing reliance by Papua New Guinea on mineral exploitation for foreign direct investment, government revenues, and foreign exchange. Gold exports accounted for the biggest share of export revenues in 2002 representing 37.5% of the total. In light of this growing dependency on mining activities, there is a correspondingly urgent requirement to address the deficiencies in the administrative, monitoring, and policing aspects of the protection of its environment.
Despite the public evidence of the damage to the environment and the ensuing affect on the people of Papua New Guinea by mining activities; and despite universal condemnation of these activities and the companies responsible; the companies continue to conduct these activities without official hindrance and with little apparent concern for the long-term ramifications of their actions.
This thesis will examine the degradation resulting from the mining activities of companies in Papua New Guinea over the last three decades - particularly those of Placer Dome's Porgera gold mine, BHP's Ok Tedi gold and copper mine (the waste from both of which is dumped into the Ok Tedi and Strickland rivers which are tributaries of the Fly River and form part of the Fly River system) and Lihir Gold Limited's gold mine on Lihir Island. It will examine the extent to which the Government of Papua New Guinea may have wittingly (in the sense of a prescience as to the possible or probable likelihood of deleterious impact) or unwittingly contributed to that degradation as a result of its actions or omissions.
Studies of available literature suggest that there has been little attention paid to the subject of culpability on the part of successive PNG governments in matters of environmental damage. This research will contribute to reducing this gap in the literature by focusing on possible motives of the PNG government and its actors which precipitated those decisions and which resulted in environmental degradation. The discussion will examine the likely motivation of the PNG government in its deliberations and decisions and the extent to which corruption and incompetence may have played a role.
18
Stewart, Penelope Clair. "Minimising dilution in narrow-vein mines /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18948.pdf.
Testo completo
19
Sellami, Moncef. "Recoverable reserve estimation in multiple seam mines". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09192009-040606/.
Testo completo
20
Harvey, Harvey Blevins Madison D. Soyini. "Mines-bodies a performance ethnography of Appalachian coal mining /". Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,187.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Communication Studies (Performance Studies)." Discipline: Communication Studies; Department/School: Communication Studies.
21
Bétournay, M. C. "The stability of shallow stopes of hard rock mines". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28678.
Testo completoAbstract (sommario):
Canadian hard rock mine extraction practices have commonly created shallow stopes, 12% of which have caved to surface, from instabilities originating from stope hangingwalls, crowns or footwalls. To date, however, mine operators have applied few of the available data gathering and design tools to strike a balance between maximum economic excavation dimension and stope viability. The preference has been to use personal mining experience.Several common rock mass environments are surveyed as well as the various ways in which shallow stopes have failed. It has been found that these rock masses develop gravity-induced movement in the form of plug failures, ravelling of rock blocks, strata failures, chimneying disintegration, and rock mass block caving.
New failure-specific analytical equations are developed here for these common failure mechanisms. They address the mechanics of the failure process and incorporate the capability to arrive at the ultimate failure outline, for comparison to the location of the bedrock surface.
This research has shown that: plug failures occur along steep, uninterrupted discontinuities bounding large blocks. Plug failure potential reduces substantially with confining compressive stress, discontinuity inclination, the absence of low friction surfaces and shearing of intact rock interrupting the discontinuity. Ravelling requires little peripheral confining stress for stabilization and prevention of block falls or slides. However, inherent conditions such as shallow dipping or vertically dipping joints can cause block falls to develop to surface. Low confining stresses, resulting from multiple stope extraction in orthogonal horizontal directions, would offer conditions suitable for plug and ravelling failures. Strata failures are caused by excessive stope spans, but the limited loading received from above strata is such, that the failure cavity created is of limited vertical extent, some 25% of the stope width. Chimneying disintegration occurs in weak rock masses with low cohesion, over narrow openings that can be as deep as 275 m. The onset of chimneying disintegration can be created by compressive stresses, but develops as a result of mobilization of the rock mass by gravity in active shear. Block caving requires large spans to develop, and stabilizing could be overcome from arching stresses overcoming bulk arching strength. Controlling instability elements are tabulated for these failure mechanisms. A limit equilibrium correlation between span and cohesion for chimneying disintegration is presented, and the controlling limits between the occurrence of chimneying disintegration and block caving is discussed. Ravelling and chimneying disintegration are the most expected failure mechanisms for shallow stopes of hard rock mines. Although failure of the shallow stope may start around its periphery, stope failure to surface would likely occur in or close to the surface crown pillar.
Although the analytical equations developed require input of in situ stresses defined by numerical modelling in order to yield a precise answer, conventional numerical modelling or empirical methods are shown to be unable to predict stope failures as the analytical equations have. A step-by-step stability analysis procedure is presented, incorporating rockmass environment, expected failure mechanism(s), and applicable data gathering and anlytical methods. (Abstract shortened by UMI.)
22
Mamurekli, Deniz. "Blast-induced ground vibration modelling in open-pit mines". Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357797.
Testo completo
23
Hadjigeorgiou, John. "Studies of machine-ground interaction in surface mines". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41124.
Testo completoAbstract (sommario):
Ground preparation design encompasses problems of ground characterization, equipment selection and performance. Ground characterization has in the past been the subject of empirical diggability classification schemes based on case studies. A new system is proposed for evaluating the ease of excavation of different ground conditions, is put forward. This has been applied successfully in different field studies. While such empirical schemes are useful to mining design, there still remains a basic lack of understanding of machine-ground interaction in the excavation process. This will be essential for long term machine and method advancement.This thesis reviews the approach and methodology adopted for the development of predictive digging models in mining. Past theoretical attempts to model soil-rock cutting processes are critically evaluated and an analytical digging model applicable to fragmented rock is proposed. Physical modelling studies, concentrating on the interaction between machine and spoil characteristics, are reported. These considered in particular the digging profile propagated by cable shovel operation, the impact of geotechnical parameters on the profile, and the efficiency of digging in fragmented rock. These were undertaken in a controlled laboratory environment based upon an instrumented scale model and photographic studies. The salient parameters influencing the efficiency of the digging processes are identified and a bucket filling model for cable shovels is proposed.
24
Naidoo, Kumendrie. "Considerations for stope gully stability in gold and platinum mines in South Africa". Diss., Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-11302005-123445/.
Testo completo
25
Madalane, Thembi. "The obligation to rehabilitate mining areas : post mining activities". Thesis, University of Limpopo (Turfloop Campus), 2012. http://hdl.handle.net/10386/905.
Testo completoAbstract (sommario):
Thesis (LLM) -- University of Limpopo, 2012The study focuses on rehabilitation, since absence of proper rehabilitation process result in indelible damage to the environment. South Africa, like many other countries, is faced with many environmental problems caused by mining. These problems are particularly caused by, inter alia, abandoned mining areas without rehabilitation, inadequate environmental impact assessment after closure, inadequate financial provision for rehabilitation, and lack of monitoring and aftercare system after post mine closure. The study found that many Companies ignore laws governing prospecting, extraction and rehabilitation. The main purpose of this research is to investigate and recommend guidelines in the rehabilitation process so as to instil respect for the environment. The study therefore recommended strict legislation relating to environmental protection against mining.
26
Brendliner, Robert Lee. "Toxicity analysis of coal mining industry NPDES discharges in Southwest Virginia /". This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-01122010-020036/.
Testo completo
27
Griffin, Kenneth R. "Design Criteria for Wireless Mesh Communications in Underground Coal Mines". Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/76759.
Testo completoAbstract (sommario):
The Mine Improvement and New Emergency Response (MINER) Act of 2006 was enacted in response to several coal mining accidents that occurred in the beginning of 2006. The MINER Act does not just require underground mines to integrate wireless communication and tracking systems, but aims to overall enhance health and safety in mining at both surface and underground operations. In 2006, the underground communication technologies available to the mining industry had inherent problems that limited communication capabilities. Since the passage of the MINER Act, there have been several developing applications for underground wireless communications. Underground wireless communications allow signals to propagate and take multiple paths to destinations providing a survivable, redundant, and adaptable means of communication and tracking. An underground wireless communications allow underground and surface personnel to directly correspond to one another without being as restricted as hardwired systems. Communication systems also allow miners to be tracked underground to provide a real-time or last known post-accident position, and ensure a more efficient rescue operation.
In order to increase the overall efficiency of developing communication systems there is a need for modeling of wireless signal propagation in underground mines. Research, modeling, and analysis of wireless signal propagation in underground mines ongoing and developing with underground communications systems as the systems progress. The work on this project is based upon the Accolade system from L-3 Communications Global Security and Engineering Solutions but applies to all underground wireless mesh systems currently available. A general approach is taken to solving underground wireless communications networks to allow the design criteria to be adaptable to other communication systems belong the Accolade system.
The data is based upon measurements and field work that took place July 2007 through December 2008 in International Coal Group's Sentinel Mine in Philippi, West Virginia. Comms, a computer method developed at the Virginia Center for Coal and Energy Research at Virginia Tech, allows underground mine communication networks to be solved and analyzed. Comms was developed to solve and analyze underground wireless communication networks. The method which Comms solves communication networks is not mine specific and may be adapted to predict the performance of a system(s) in another mine.
The developed model discussed in Chapters 3 and 4 highlights the general signal loss parameters that are encountered by wireless signals in a mine. The model predicted the signal strength observed when encountering those categorized signal losses within 16 percent of the data measured during a mine survey. The model has been developed in a general manner to allow future investigation and pinpointing of additional interferences that occur within the underground environment.
Wireless communications have proven to be the way of the future and will continue to be integrated into underground coal mines as mandated by the MINER Act. Wireless communications systems are a redundant and survivable means of communication that will be utilized in not only emergency and rescue efforts but daily operational communication as well.Master of Science
28
Abbasy, Farzaan. "An investigation into application of geothermal energy in underground mines". Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123077.
Testo completoAbstract (sommario):
Energy conservation is an important policy for every nation. Exploiting sustainable energy resources has gained ground due to shortages and increasing prices of fossil fuels. Mining represents a significant portion of Canada's resource-based industry sector and consumes a huge amount of energy for operation and post-mining activities. Therefore, any cut in energy consumption lowers costs and increases profits. Underground mines have excellent potential for implementation of geothermal energy systems using one of two methods. In the first, underground mine water that has flowed through warm layers of the ground and found its way to mine openings is pumped to the surface for use in open loop geothermal cycles. In the second method, underground openings and spaces that provide easy access to low-to-medium temperature rock formations are used in closed loop geothermal cycles. This research primarily focuses on providing guidelines for using geothermal energy in underground mines and comprises two main parts. The first involves surveying 12 underground mines across Canada to evaluate operation of open loop geothermal system in these and similar mines. The second part investigates the potential of heat recovery from backfilled mine stopes. For this purpose, thermal properties of cemented mine backfill are investigated, the significance of influential parameters is quantified and a thermal conductivity prediction model is introduced. In addition, an experimental physical model is built to study heat transfer in mine backfill and evaluate different arrangements and influential parameters. An analytical model is developed based on the cylindrical coordinate system with finite length and the model is validated for heat transfer in backfill. Finally, a case study of a backfilled stope is presented.L'économie d'énergie est une politique importante pour tout pays. L'exploitation des ressources énergétiques durables est devenue plus importante en raison des pénuries et la hausse des prix des combustibles fossiles. L'exploitation minière représente une partie importante du secteur de l'industrie basée-sur-les-ressources au Canada et consomme une énorme quantité d'énergie pour l'opération ainsi que les activités post-extraction minières. Pour cette raison, toute réduction de la consommation d'énergie réduira les coûts et augmentera les profits. Les mines souterraines ont un excellent potentiel pour la mise en œuvre des systèmes d'énergie géothermique en utilisant l'une des deux méthodes suivantes. Dans la première méthode, l'eau dans les mines souterraines qui coule et passe à travers les couches de sol chaudes trouvant son chemin vers les ouvertures, est pompée vers la surface pour être utilisé dans des cycles géothermiques en boucle ouverte. Dans la seconde méthode, des ouvertures et des espaces souterrains qui offrent un accès facile aux formations rocheuses ayant une basse ou moyenne température sont utilisés dans les cycles géothermiques en boucle fermée. Cette recherche se concentre principalement sur la fourniture des directives pour l'utilisation de l'énergie géothermique dans les mines souterraines en comprenant deux parties principales. La première partie, comprend l'enquête de douze mines souterraines à travers le Canada afin d'évaluer le fonctionnement des systèmes géothermiques en boucle ouverte. La deuxième partie examine le potentiel de récupération de chaleur sur des remblais miniers cimentés. À cet effet, les propriétés thermiques de remblai minier cimenté sont étudiées, la signification des paramètres influents est quantifiée et un modèle de prédiction de la conductivité thermique est introduit. En plus, un modèle physique expérimentale est construit pour étudier le transfert de chaleur dans les remblais miniers et d'évaluer les différents arrangements et les paramètres influents. Un modèle analytique est développé sur la base du système de coordonnées cylindriques avec une longueur finie; et le modèle est validé pour le transfert de chaleur dans le remblai. Finalement, une étude de cas d'un chantier remblayé est présentée.
29
Maritz, Liezl. "Ecological role of mining ponds in Southern Coastal Mines, Namibia". Master's thesis, Faculty of Science, 2021. http://hdl.handle.net/11427/32833.
Testo completoAbstract (sommario):
Targeting marine diamondiferous deposits along the south-western Namibian coastline has involved the construction of seawall berms to advance the coastline and permit mining in previously subtidal areas. Large areas are mined out to bedrock level by the removal of overburden (sand and gravel), and after mining is complete, areas behind the seawalls fill with seawater, creating a series of coastal marine ponds that have the potential to function as saline wetlands corresponding to closed estuaries. The study site lies north of the Orange River mouth, within the Tsau//Khaeb (Sperrgebiet) National Park, to which the public has restricted access due to diamond mining in the area. Consequently, there is a focus on biodiversity conservation and the overall objective of this thesis was to determine the ecological value of the mining ponds by investigating whether they harbour sufficient biodiversity to qualify as a viable alternative ecological habitat, rather than restoring them to their original state as backfilled, revegetated dune areas. The study area, approximately 75 kilometres in length, was divided into north, middle and south sections, according to the age and status of mining activities, and I first assessed whether ponds in these three areas differed in their physical properties (Chapter 1). To determine whether the ponds serve as a useful ecological role worth preserving, I then investigated the diversity and amount of saltmarsh vegetation (Chapter 2), bird species (Chapter 3) and fish (Chapter 4) currently benefiting from these mining ponds. Ponds in the north are older and hypersaline whereas the south and middle ponds are younger and closely approach physical conditions in the sea. Diurnal fluctuations in oxygen concentration took place, but oxygen levels never dropped below 80% and were thus not limiting. After about 15 years, ponds developed salinities in excess of 80‰, which is likely to set limits on their ecological viability. Most ponds supported saltmarshes, but only a single species, Salicornia natalensis, grew around them. Its abundance was greatest around old ponds, but its health decreased with salinity. Wind emerged as a likely means of dispersal among ponds. The ponds supported a rich avifauna, averaging 11028 birds per count for all ponds combined; 36 species were recorded, ten being endemics, and five being listed in Namibia's Red Data Book. Numbers were highest for ponds that were being ‘dewatered' to remove water prior to mining, as this exposed a rich benthic epifaunal source of food. Blacknecked Grebe, Cape Cormorant, Greater and Lesser Flamingos, Kelp Gull and Common Tern were the most abundant birds. Salinity did not limit bird numbers or diversity, so the northern high-salinity ponds may continue to serve as bird habitat for periods of time much greater than the 15 years after which they become hypersaline. In comparison with nine other wetlands in the region, the ponds had great numbers, diversity, densities, and numbers of threatened species than about half of these wetlands, many of which are considered Important Bird Areas (IBAs). In many cases, they also supported more species that had numbers in excess of 1% of the southern African population than these IBAs. Only two species of fish commonly occurred in the ponds, the west coast steenbras Lithognathus auratus and the southern mullet Chelon richardsonii, although small numbers of two other marine species were recorded. The diversity of marine fish was thus low, even by the impoverished standards of west-coast estuaries. Unexpectedly, there were no significant differences between the ichthyofauna of ponds in the north, middle and south, nor was there any relationship between total fish numbers and salinity. Body condition of steenbras was lowest in the hypersaline north ponds, and their stomach contents contained a low diversity of food items there. The presence of recruits and the range of gonadal states suggested that both species bred in the ponds. Steenbras proved to be protandrous, with females dominating larger size classes. Growth rates of both species were faster in the ponds than in the adjacent sea, and mullet achieved substantially greater sizes in ponds. Thus, the ponds do serve as viable ecosystems, albeit with a limited range of saltmarsh and fish species, and support an impressively diverse avifauna. Their long-term viability will, however, become limited by rising salinity as their age increases.
30
Crellin, David J. "Ground instability associated with mineworkings and groundwater in opencast coal mines". Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375916.
Testo completo
31
Nüchter, Andreas, Jan Elseberg e Peter Janotta. "Towards mobile mapping of underground mines". Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2018. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-231186.
Testo completoAbstract (sommario):
Mobile laser scanning systems automate the acquisition of 3D point clouds of environments. The mapping systems are commonly mounted on cars or ships. This paper presents a flexible mapping solution mounted on an underground vehicle that is able to map underground mines in 3D in walking speeds. A clever choice of hard- and software enables the system to generate 3D maps without using GPS (global positioning system) information and without relying on highly expensive IMU (inertial measurement unit) systems.
32
Hudyma, Martin Raymond. "Analysis and interpretation of clusters of seismic events in mines". University of Western Australia. School of Civil and Resource Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0054.
Testo completoAbstract (sommario):
Spatial clustering of seismic events in mines has been widely reported in literature. Despite obvious visual correlations between spatial clusters of seismic events and geomechanical structures in mines (such as pillars, dykes and faults), very limited research has been undertaken to utilise this information to filter seismic data. A linkage between spatial seismic event clusters and discrete rockmass failure mechanisms is tenuous and not well established using current seismic analysis techniques. A seismic event clustering methodology is proposed. The first component of the methodology uses a complete-linkage (CLINK) clustering routine to identify relatively compact clusters of seismic events. The CLINK clusters are then subjected to a singlelink clustering process, which uses spatial location and seismic source parameters as similarity measures. The resultant
33
Abolfazlzadeh, Yousef. "APPLICATION OF SEISMIC MONITORING IN CAVING MINES". Thesis, Laurentian University of Sudbury, 2013. https://zone.biblio.laurentian.ca/dspace/handle/10219/2110.
Testo completoAbstract (sommario):
Comprehensive and reliable seismic analysis techniques can aid in achieving successful inference of rockmass behaviour in different stages of the caving process. This case study is based on field data from Telfer sublevel caving mine in Western Australia. A seismic monitoring database was collected during cave progression and breaking into an open pit 550 m above the first caving lift.
Five seismic analyses were used for interpreting the seismic events. Interpretation of the seismic data identifies the main effects of the geological features on the rockmass behaviour and the cave evolution. Three spatial zones and four important time periods are defined through seismic data analysis.
This thesis also investigates correlations between the seismic event rate, the rate of the seismogenic zone migration, mucking rate, Apparent Stress History, Cumulative Apparent Volume rate and cave behaviour, in order to determine failure mechanisms that control cave evolution at Telfer Gold mine.
34
Noppé, Mark Adrian. "Geological controls for coal exploration and mining". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005566.
Testo completoAbstract (sommario):
The identification and interpretation of geological features is essential for the planning and ultimate success of any mining venture. Examples of geological features significant for mining are presented, and their identification during exploration discussed. In particular, the importance of coal qualities, seam thickness and seam elevation are emphasised in relation to longwall mining. Geostatistical analysis provides a powerful tool for improving the prediction and decision-making capabilities of both exploration and mine geologists. The availability of geostatistics, and the benefits resulting from its application, are demonstrated using actual data for calorific value, seam thickness and seam elevation. Contamination of run-of-mine coal is a common problem on highly-mechanised collieries. The problem generally arises from over-cutting of the designated mining horizon. A practical system for monitoring and controlling contamination on a mechanised bord-and-pillar and longwall colliery is presented. The results and benefits of applying such a system are cited for an actual longwall colliery. Numerical geological predictions are not always reported in terms of the reliability of such estimates. Many of these values can be reported in terms of confidence limits, particularly for routine grade control purposes. The methods and benefits of such reporting are described and illustrated by way of examples for calorific value and contamination levels.
35
Mawdesley, Clare A. "Predicting rock mass cavability in block caving mines /". St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16404.pdf.
Testo completo
36
El-Mherig, A. M. "A study of the stability of jointed rock slopes in surface mines". Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371279.
Testo completo
37
Young-On, Harold. "An economic evaluation of backfilling in Virginia's coal mines". Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-02132009-172231/.
Testo completo
38
Zahiri, Hani. "A predictive GIS methodology for mapping potential mining induced rock falls". Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060725.120628/index.html.
Testo completo
39
McCoy, Kurt J. "Estimation of vertical infiltration into deep Pittsburgh coal mines of WV-PA a fluid mass balance approach /". Morgantown, W. Va. : [West Virginia University Libraries], 2002. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=2745.
Testo completoAbstract (sommario):
Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains x, 150 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 87-90).
40
DeLeon, Sarah Wade Dickinson. "Jewels of Responsibility from Mines to Markets:". ScholarWorks @ UVM, 2008. http://scholarworks.uvm.edu/graddis/65.
Testo completoAbstract (sommario):
Artisanal and small-scale mining (ASM) are important sources of income for impoverished rural populations in many developing countries. Poor labor and environmental conditions often prevail because governments lack the capacity and sometimes the will to responsibly control ASM. At the other end of the supply chain, corporate social responsibility (CSR) strategies increasingly require jeweler’s suppliers to control social and environmental aspects of mining. In a sense, jewelry and mining corporations are voluntarily taking the issue of governance into their own hands. A combination of CSR and revenue-centric development strategies has the potential to further marginalize poor, rural populations who depend on ASM. It is therefore important to examine how ASM has been affected by global social responsibility trends, why it is often left out and to find ways that ASM populations can be successfully integrated into planning for sustainable development and socially responsible business. Gemstones and gold are economically the most important global commodities for ASM populations and precious colored gemstones are rarely mined on a large-scale. Ethnographic research was undertaken to explore how global social responsibility strategies interact with local realities of ASM colored gemstone and gold production. Burma, Madagascar and Colombia each present cases with clear interaction between global CSR trends and ASM, and combined provide a range of public policies with regards to rural populations who depend on ASM. Informal interviews and industry observations were conducted with a range of stakeholders in the global precious mineral trade and mineral development sector. Semi-structured interviews were recorded with key informants for each case study and these were triangulated with internal documents, press releases and articles. Burma illustrates a case where global CSR is attempting to halt ASM because of poor governance and human rights violations. Madagascar illustrates a case where governance and education are improving but widespread poverty and a legacy of corruption has so far prevented the direct integration of ASM into CSR strategies. In the case of Colombia, one region has successfully connected ASM with the global CSR dialogue by designing and implementing a certification program to effectively valorize and govern ASM production. Major findings reveal that (1) CSR in the mineral sector is a contentious and political issue with a range of stakeholder viewpoints; (2) a bottom-up, process-oriented approach can successfully drive economic and social improvement in ASM commodity chains; and (3) community empowerment, education, youth leadership and social networking appear to be key factors for driving production of ASM minerals that can comply with social and environmental standards.
41
Zhao, Yixian. "Algorithms for optimum design and planning of open-pit mines". Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185842.
Testo completoAbstract (sommario):
A graph theory oriented algorithm for optimal ultimate pit limit design is developed. Mathematical proofs of optimality and convergence are given. The algorithm works on a 3-D block mine model and formulates the model into a directed graph consisting many trees. The vertices in the graph are identified with the blocks in the model and the imposed arcs in the graph represent pit slope constraints. The formation of each directed tree is based more on the ore-waste support concept than geometric constraints alone. The algorithm efficiently handles the joint support and re-allocation problems. The theoretical proof shows that the new algorithm is consistently faster than the well known Lerchs-Grossmann's (LG) algorithm, which is the only algorithm developed in the past one-quarter century capable of producing a true optimum pit limit. The case study results show that the new algorithm is able to generate the optimal ultimate pit limit for a model with 80 columns x 80 rows x 40 levels on an IBM PC AT 80286 microcomputer in 115 minutes. The indirect comparison was made between the results of the new algorithm and the results obtained by P. Huttagosol (1988, 1989) using the LG algorithm. P. Huttagosol optimized a smaller mine model than the one optimized by the new algorithm in 535 minutes of VAX8600 CPU time. The comparison between 535 minutes of VAX8600 CPU time for a smaller model with 115 minutes PC AT processing time for a bigger model clearly indicates that the new algorithm is significantly faster than the LG algorithm. This study also investigates both proposed mathematical optimization approaches and the popular trial and error "pushback" approach to long range mine planning. Both the theoretical analysis and numerical examples demonstrate it is impossible to obtain the optimal solution to mine production scheduling by the approach combining the Lagrangian relaxation with the ultimate pit limit algorithm. The non-convergence due to redundant optimal solutions and the non-convergence due to the requirement of advanced stripping are identified with the proposed approach. The investigation clarifies the long-time misunderstood concept and proves the impossibility of such a research direction itself. Finally, some problem solving techniques which play important roles in the computerized mine planning and grade control are developed and discussed. Specifically, they are: (1) point-in-polygon algorithm, (2) polygon area algorithm, (3) polygon clipping algorithm, (4) blast hole data collection, validation and database maintenance, and (5) the interactive graphics ore-waste delineation.
42
Hamilton, James F. "A study of the fine gold recovery of selected sluicebox configurations". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28384.
Testo completoAbstract (sommario):
The recovery of placer gold from 20 mesh to 150 mesh in common sluicebox configurations was investigated. Two types of riffles, 1-10H expanded metal (1.5"x.75"x.25") and 1.25" angle iron riffles (dredge riffles), were used in conjunction with 3/8" thick "Nomad" matting for 25 tests. The effects of variations in upper feed size, water flow rate, sluice gradient, and solids feed rate on the recovery of placer gold particles are documented.
The gold and test gravel were obtained from the Teck Corporation sluicing operation on Sulphur Creek, Yukon Territory during July, 1985. Approximately nine troy ounces of placer gold and fifteen tons of gravel were transported to Vancouver.B.C. A test sluice facility was constructed in Coquitlam,B.C. to simulate operating conditions in a typical Yukon placer operation. The sluicebox was 12" wide and 8' long with clear plexiglass sidewalls. Screened gravel of either 3/4" or 1/4" upper feed size was fed to this sluice from a hopper at rates of up to 1260 lb/min. The water pumping capacity was a maximum of 400 USGPM. Between 75 and 90 grams of each of three sizes of placer gold (-20+28#, -35+48#, -65+100# ) were premixed with the gravel for most tests. The final test used 25 grams of -100+150 mesh gold.
Sluicing, when properly controlled, was found to be a highly effective means of concentrating placer gold as small as 150 mesh. Expanded metal riffles were far superior to dredge riffles in concentrating gold of this size range. Recovery of the -65+100# size fraction frequently exceeded 90% when using expanded metal riffles. Visual observation of eddies formed downstream of the riffles showed that scour depth between riffles was the one characteristic of the slurry flow that gave the best indication of the resulting gold recovery. For expanded metal, scour depths between 1/2 and 3/4 of the riffle depth were found the most effective.Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
43
Hunt, Ortiz Mark A. "Prehistoric mining and metallurgy in south west Iberian peninsula /". Oxford : Archaeopress, 2003. http://catalogue.bnf.fr/ark:/12148/cb39142582n.
Testo completo
44
Nüchter, Andreas, Jan Elseberg e Peter Janotta. "Towards mobile mapping of underground mines". TU Bergakademie Freiberg, 2017. https://tubaf.qucosa.de/id/qucosa%3A23181.
Testo completoAbstract (sommario):
Mobile laser scanning systems automate the acquisition of 3D point clouds of environments. The mapping systems are commonly mounted on cars or ships. This paper presents a flexible mapping solution mounted on an underground vehicle that is able to map underground mines in 3D in walking speeds. A clever choice of hard- and software enables the system to generate 3D maps without using GPS (global positioning system) information and without relying on highly expensive IMU (inertial measurement unit) systems.
45
Koufos, Katarina. "Assessing the potential to implement open loop geothermal systems in Canadian underground mines". Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107715.
Testo completoAbstract (sommario):
Many parts of the world are introducing geothermal heat pumps as alternatives to conventional heating and cooling systems. This thesis investigates how this renewable energy resource can be exploited using underground mine water from active mines in Canada. A few cases located in Europe and North America are presented where buildings are utilizing thermal energy generated from open loop mine water systems found in nearby abandoned mines. This report involved two studies. The initial one is a preliminary survey involving twelve active mine sites in Canada. Site visits were conducted at all twelve mines to collect information about the operation, mine water temperature and water pumping rates. From this data, the thermal capacity of the underground resource was calculated and verified using heat pump catalogues. Economic and environmental assessments were conducted for each proposed geothermal heat pump design. These preliminary results were promising and a larger assessment, which included a total of 23 mines, was conducted. The results from this assessment found that the overall potential heat gain from these mines is 20,900 kW annually, which translates into heating 69,150 average Canadian homes. Canadians have the potential to realize an annual savings from $1.5 to $4.9 million, with a potential reduction in carbon dioxide emissions varying from 16,850 to 19,300 tonnes per year.Dans plusieurs parties du monde, l'installation de pompes à chaleurs géothermiques agissant comme alternatives aux systèmes de chauffage traditionnels et devient une tendance importante. Ce document a l'intention d'examiner cette forme d'énergie renouvelable en utilisant comme source l'eau qui s'écoule des mines souterraines au Canada. Certains exemples de ces types de systèmes, retrouvés principalement en Europe et en Amérique du Nord, seront présentés. Pour les cas mentionnés, plusieurs bâtiments et immeubles utilisent l'énergie géothermique générée par des systèmes d'eau à boucle ouverte installés dans des mines abandonnées. De plus, des études préliminaires ont été acheminées pour douze sites miniers en opération au Canada. Des visites souterraines ont été menées à chaqu'un de ces sites pour recueillir des informations importantes concernant les activités minières, les températures des eaux souterraines et les capacités de pompage. Les capacités thermiques des eaux souterraines ont été calculées et ensuite comparées aux spécifications techniques des pompes à chaleur. Les résultats préliminaires ont été encourageants, incitant donc une enquête pour déterminer le potentiel de cette source d'énergie à l'échelle nationale. Cette évaluation comprend un total de vingt-trois sites miniers. Leur évaluation a constaté que le potentiel de gain de chaleur combiné est de 20,900 kW. Ce gain peut fournir un an de chauffage pour l'équivalent de 69,150 maisons. Les économies annuelles qui peuvent être réalisées en remplaçant un système de réchauffement traditionnel (soit au gaz naturel ou chauffage électrique) par un système géothermique dont la source provient des opérations minières, sera entre $1.5 et $4.9 millions. De plus, l'exploitation de cette forme d'énergie a le potentiel de réduire les émissions de dioxyde de carbone par un facteur de 16,850 à 19,300 tonnes par année.
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Squelch, Andrew Peter. "Application of virtual reality for hazard awareness training in South African gold mines". Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243505.
Testo completo
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Mengwe, Moses Seargent. "Towards social impact assessment of copper-nickel mining in Botswana". Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1443.
Testo completoAbstract (sommario):
This research study is more of an initiative towards Social Impact Assessment of copper-nickel mining in Botswana. The specific objectives of the study were centred on the assessment of the social impacts of copper-nickel mining in Botswana from the initial mining stage of exploration, surveying and mine site development to mine closure. The study was carried out under the broad hypotheses that mining influences population movement that impact on areas of mining; mining activities have both economic benefits and deleterious social impacts on the local communities found in the areas where mining is taking place; and mine closure has far reaching socio-economic, investment and developmental implications over and above the obvious interests of project owners. To achieve the broad aim as summarised above, the research study used a multi-disciplinary methodology and approach that required several kinds of expertise and sources of information. Hence it used both primary and secondary sources centred on interactive informative interviews, site visits and observations, questionnaires, census data records, mining companies’ publications, published textbooks and journal articles. The research study comprised of three different mines operated by three different mining companies in three varied socio-cultural and ethnic regions of Botswana. First was a detailed Social Impact Assessment of the initial phase of exploration, surveying and mine site development represented by Mowana mine project operated by African Copper in the rural areas of Dugwi and Mosetse. This case study yielded results showing that the social impacts of mining in the area are diverse and extensive. The findings suggest that the impacts relate not only to the possible economic benefits of foreign exchange, employment, the optimal use of available mineral resources and the possible development of Dugwi and Mosetse villages, but extends to the deleterious social impacts. The results also indicated that the social impacts have just begun in the two communities. Hence they point towards a possible disruption within the socio-cultural system of the local people if serious mitigation measures are not put in place; thus suggesting that the early stages of exploration and mine site development results in the most conflict between the mine and the local people. Second was a comprehensive Social Impact Assessment of Tati-Nickel Phoenix mining project in the peri-urban areas of Matshelagabedi and Matsiloje areas representing the mining stage of mine production and expansion. The results from this case study suggest that during vi mine production and expansion, many people were relocated. However, the overriding impression gained from the case study was Tati-Nickel Mining Company’s elaborate corporate policies that suggested good corporate governance and best practices that promote sustainable development. A notable milestone on good corporate governance and best practice that the other two case studies (mining company) could benchmark on is Tati-Nickel’s corporate social responsibility programme that has been designed to ensure that the communities within a fifty kilometre mine radius benefit from the mine. The results from the case study also distinguished the mining stage of production and expansion from the other two because it is associated with the deep entrenchment of the social impacts into the communities near to mining areas. Third was a detailed Social Impact Assessment on Bamangwato Concession Limited mine in the industrial town of Selebi-Phikwe. The case study represented the stage of mine closure. Through the findings of this case study, it became apparent that the economic dependence of Selebi-Phikwe on mining has seen the town developing into a mining town, increasing its vulnerability at mine closure. The results from the case study further suggest that mine closure will degrade the socio-economic sector of the town with ever far reaching socio-economic implications as many people lose their gainful employment, hence suggesting that a possible complete mine closure will be the most traumatic phase leading to major social conflict within the area. Thus the results suggest that at mine closure, the deleterious social impacts will overspill to other areas in Botswana with disastrous effects for the economy of the country. The results yielded through this study established in clear and passionate language that copper-nickel mining in Botswana influences population movements that lead to positive and negative impacts on the communities found in mining areas. Another major finding of the study is that copper-nickel mining activities have both economic benefits and deleterious social impacts on the local communities, hence the recommendation that the copper-nickel mining companies should embrace the concept of sustainable mining for sustainable development to avoid most of the negative impacts of their operations on the local communities.
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Matidza, Murendeni. "Green synthesis of geopolymeric materials using Musina Copper Mine Tailings: a case of beneficial management of mine tailings". Diss., 2019. http://hdl.handle.net/11602/1467.
Testo completoAbstract (sommario):
MENVSCDepartment 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
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Prakash, Bisleshana Brahma. "Design of Stable Slope for Opencast Mines". Thesis, 2009. http://ethesis.nitrkl.ac.in/1333/1/10505020.PDF.
Testo completoAbstract (sommario):
Slope stability analysis forms an integral part of the opencast mining operations during the life cycle of the project. In Indian mining conditions, slope design guidelines were not yet formulated for different types of mining practices and there is a growing need to develop such guidelines for maintaining safety and productivity. Till date, most of the design methods are purely based on field experience, rules of thumb followed by sound engineering judgment. During the last four decades, the concepts of slope stability analysis have emerged within the domain of rock engineering to address the problems of design and stability of excavated slopes. The basic objective of the project is primarily addressed towards: a) Understanding the different types and modes of slope failures b) Designs of stable slopes for opencast mines using numerical models. Analyses were conducted using the finite difference code FLAC/Slope. The work was aimed at investigating failure mechanisms in more detail, at the same time developing the modeling technique for pit slopes. The results showed that it was possible to simulate several failure mechanisms, in particular circular shear and toppling failure, using numerical modeling. The modeling results enabled description of the different phases of slope failures (initiation and propagation). Failures initiated in some form at the toe of the slope, but the process leading up to total collapse was complex, involving successive redistribution of stress and accumulation of strain. Significant displacements resulted before the failure had been developed fully. Based on parametric studies it can be concluded that friction angle plays a major role on slope stability in comparison to Cohesion.
Keywords: Slope stability, open pit mining, numerical modeling, rock mass strength, failure mechanisms.
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Badal, K. Kujur. "Blast Vibration Studies in Surface Mines". Thesis, 2010. http://ethesis.nitrkl.ac.in/1788/1/THESIS-BADAL_KUMAR_KUJUR-10605005BLAST_VIBRATION_STUDIES_IN_SURFACE_MINES.pdf.
Testo completoAbstract (sommario):
Blasting is very important process for mining operation and a lot of explosive is used for this purpose. The blasting process and usage of explosives, however, remain a potential source of numerous human and environmental hazards. Various studies indicate that fragmentation accounts for only 20-30% of the total amount of explosive energy used. Rest of the energy is lost in the form of ground vibration, fly rock, air overpressure and noise. The specific problem associated with ground vibrations represents the human response to them. Blasting vibrations may also cause a significant damage to nearby buildings or various structures. In this project blast vibration study is done and it is interpreted for its effects in reference to the standards set by DGMS.
The study has been done with the help of geophones and Blastmate8.0 software. First of all the blasting operations were monitored through geophones at distances of 100m, 200m and 300m. The data obtained from the instrument were interpreted by Blastmate software and the graphical output was obtained from it. The Peak Particle Velocity (PPV), maximum charge per delay, air over pressure was recorded for each blast. After that the various observations were compared with the standards to determine the conclusion.
From the analysis of blasts vibration at the mines it was determined that the vibration level was less than 5 mm/sec for the blasts when recommended amount of charge per delay or safe charge per delay was used. The air overpressure value determined was in between 114 & 127.6 dB (L).
The results determined from the project indicates that the peak particle velocity, air overpressure generated due to blasting were within the limits. The safe charge per delay for the blasting operation was determined from the study.