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A major objective in the design stage of an underground mine is the reliable prediction of roof falls' size, frequency and location. Probabilistic simulation of potential roof control problems allows a designer to test the performance of competing mine layouts against assumed roof conditions. By comparing different roof control plans using the simulation, the option that provides the lowest overall cost can be selected. The program ROCSIM (Roof control Optimization Cost Simulation) was developed to provide a theoretical solution to this problem. The occurrence and frequency of roof falls are related to the type of roof support, support density, geology, structural discontinuities, location in the mine, and elapsed time between mining and the roof fall. Using a Roof Rating System (RRS) developed for this research, a numerical rating can be given to each area of roof. Using this rating, specific parameters can be assigned to these probability distributions to simulate the occurrence of roof falls within a given geologic setting. Once the location of a roof fall is determined, a cost is calculated taking into account the production delay that would result and the direct cost of cleaning up the fall and resupporting the roof. Assigning a cost to a roof fall allows the comparison of competing roof support designs relative to their overall cost. The final decision on the amount of support and room width must be determined based on legal restraints and minimization of mining costs. / Master of Science

The Appalachian coal mining region is subject to a number of environmental and economic problems; many are a result of the steeply sloping topography. The extensive surface mining activities in the area appear to offer the opportunity to produce more favorable landforms at minimum marginal costs. Yet, despite this apparent opportunity and the success of research efforts to develop improved mine soil construction and revegetation techniques, the majority of the mining and reclamation activities in the Virginia coal region are carried out using conventional methods: reconstructing steeply sloping mining areas to their approximate original contours. The purpose of this research was to estimate the costs of coal surface mine reclamation methods designed to prepare mined lands for improved use in areas of steeply sloping topography. During the course of this research, a computer-based mining and reclamation cost estimating system was developed. COSTSUM is a set of seven programs designed to analyze data from active surface mining sites to determine spoil handling and reclamation costs. OPSIM is a surface mining simulator designed to estimate the differences in spoil handling costs among reclamation and postmining landform alternatives. This cost-estimating system was utilized during an intensive study of mining and reclamation costs at a surface mining site in Wise County, Virginia, where a number of improved reclamation practices were implemented. At this site, a steeply sloping premining topography was transformed to a postmining landform containing an extensive near-level area covered with deep, uncompacted, potentially productive mine soils. Analysis of daily records of operations revealed that the cost of mining and reclaiming this site was comparable to industry average costs in the area in spite of departure from conventional methods. The results of simulation procedures indicated that the cost of mining so as to produce this landscape was less than than the estimated cost of conventional mining methods. Since the topography of the site is typical of surrounding areas, there are opportunities to produce near-level landforms with deep, productive soils as a byproduct of coal surface mining activities. / Ph. D.

Thesis (MBA)--Stellenbosch University, 2001. / Some digitised pages may appear illegible due to the condition of the original hard copy / ENGLISH ABSTRACT: Successful organisations keep a well-balanced fit between their strategy, structure, processes, reward system and culture. Any significant change in any of the elements requires management to rethink and probably redesign the rest of the elements. Tshikondeni Coal Mine went through various changes the last few years. These changes were brought about by, amongst other things, a re-engineering project, production expansion and the appointment of new management A significant portion of the employees was newly appointed. Some of the older employees were appointed in other positions, or were required to do different work. Tshikondeni had to make sure that employees were equipped with the needed competency to do their job to the required standard and in a safe manner. The process started by ensuring that employees' medical profile fit that required by their jobs. They were also trained in identifying the hazards associated with their jobs and how to minimise exposure to risks. The gap between the competencies required for each job and that possessed by the job incumbent was identified. Training was designed to fill the identified gaps. Iscor management's annual salary increase is performance driven. The process of designing post profiles, competency documents and personal performance contracts is described. The link between the personal performance contract, the annual salary increase and the personal development plan is discussed. There is still no clear link between the annual salary increase of operational employees and their performance. Plans are in place to eventually reward all employees on a performance driven basis. The training section on Tshikondeni Mine was designed to support business objectives. It is also aligned with the trends experienced in modern training. The section, amongst other things, caters (through the use of an interactive multi media system) for the bulk of mining employees who can't read or write. All training information is kept on a central database. Employees must not only be able to do their job, but also willing or motivated to do it. Management created a work and home environment conducive towards motivated employees. A psychosocial study was done to. determine how employees and their families felt towards their environment. The results helped management to focus energy where problems were identified. Problems and pitfalls encountered during the process to ensure competency are discussed. The process followed by the mine is elucidated with modern trends, statements, remarks and suggestions found in literature. / AFRIKAANSE OPSOMMING: Hoë prestasie organisasies se strategië, strukture, prosesse, vergoedingstelsels en kultuur is in balans met dit wat sukses voorskryf. Enige wesenlike verandering in enige van die elemente kan veroorsaak dat die res van die elemente herbesoek en moontlik herontwerp moet word. Tshikondeni Steenkoolmyn het groot veranderinge oor die afgelope aantal jare beleef. Hierdie veranderinge was onder andere veroorsaak deur en proses herontwerp, produksie uitbreiding en die aanstelling van nuwe bestuur. en Beduidende hoeveelheid van wernemers was nuut aangestel. Van die ouer werknemers was aangestel in nuwe poste of was verwag om nuwe take te verrig. Tshikondeni moes verseker dat werknemers toegerus was met die nodige bevoegdheid om die werk te kan doen volgens die verlangde standaard en op en veilige manier. Die proses was begin deur te verseker dat werknemers se persoonlike mediese profiel pas by die profiel benodig deur hulle poste. Hulle was opgelei in die identifisering van gevaar in hulle werksomgewing en hoe om die risiko van blootstelling aan die gevaar te minimeer. Die gaping tussen werknemers se bevoegdhede en dié verlang deur hulle poste was geïdentifiseer. Opleiding was ontwikkel om die gapings aan te spreek. Iscor Bestuur ontvang jaarliks enprestasie gebasseerde salaris verhoging. Die proses wat gevolg is met die ontwerp van pos profiele, bevoegdheidsdokumente en persoonlike prestasiekontrakte word beskryf. me verhouding tussen die persoonlike prestasie kontrak, die jaarlikse salaris aanpassing en die persoonlike ontwikkelingsplan word bespreek. Daar is tans nie en duidelike ooreenkoms tussen die jaarlikse salaris aanpassing wat bedryfspersoneel ontvang en hulle prestasievlakke nie. Iscor het wel planne in plek om uiteindelik aan alle werknemers In prestasie gebasseerde vergoeding te betaal. Die opleidingseksie op Tshikondeni is ontwerp om besigheidsdoelwitte te ondersteun. Dit is ook belyn met moderne neigings met betrekking tot opleiding. Die seksie bedien, onder andere die grootste gedeelte van mynbou werknemers wat nie kan lees en skryf nie (met behulp van In interaktiewe multi media stelsel). Alle opleidings inligting word gestoor op In sentrale databasis. Werknemers moet nie net in staat wees om hul werk te kan doen nie, maar moet ook gemotiveerd wees om die werk te wil doen. Bestuur streef daarna om In werk- en huis omgewing te skep wat werknemers motiveer. In Psigososiale studie is gedoen om te bepaal hoe dat wememers en hulle gesinne voel ten opsigte van hulle omgewing. Die resultate het gehelp om bestuur se aandag en energie te fokus om probleme op te los. Probleme en slaggate ondervind tydens die bevoegdheidsproses word bespreek. Die proses gevolg word toegelig met moderne neigings, stellings, opmerkings en voorstelle soos wat gevind word in die literatuur.

Thesis (MBA)--Stellenbosch University, 2000. / During the last five years, successful mine closure has become one of Iscor Coal Business primary strategic focus areas. Three Iscor Coalmines are currently in different stages of closure, i.e. North Field, Hlobane and Dumacol and the demand on management time spent on this issue is increasing. The changing legal environment, especially issues concerning rehabilitation and mine closure, demands that every company must take full responsibility for any detrimental effect that their operations may have on the environment. This study concerns itself with establishing a generic procedure for mine closure. The interface with all stakeholders, external and internal, is considered. The primary focus areas are determined and the most important issues within each area are discussed in such a way that operational managers and strategists could use it as base knowledge for future closures. Applying the model to an actual closure process, i.e. the closure of Durnacol Coalmine, tested the validity of the model and it was verified that the process could be used as a base for future reference.

Thesis (MBA)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In this study, a cost benefit analysis was done to determine the best possible methods for postmining reclamation. A comparison was made between a conventional method with additional organic material added to the soil and a Backgrounding method where cattle are reared on the land. The best method, according to the financial model that was built, was the method of Backgrounding cattle on the rehabilitated land. The main reason for this outcome may be due to the fact that the meat that is produced is a high value product. It might not be practically applicable to mines at this stage, but the calculation provides an insight into the possibilities that reclaimed mine land holds for the agricultural industry.

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

Thesis. (D. Tech. - Business, Faculty of Management Sciences)--Vaal University of Technology, 2010. / The study explored the South African coal mining industry and it’s role players to establish the causes of the bottlenecks/constraints experienced in the coal mining industry supply chain. A qualitative research paradigm methodology was used. Both theoretical and philosophical assumptions were utilised with inferences from and references to works by other researchers to broaden the knowledge horizons for the study. Thirteen supply chain executives and professionals from the key role players in the coal mining industry were interviewed and provided invaluable input for the study. The study determined the presence of communication barriers between the industry role players in the public and private institutions that culminated in main themes and sub-themes being established from which the industry constraints were uncovered. The study identified six main constraints affecting the various role players within the coal mining supply chain and it culminated in the model that would enable the industry to minimise such constraints. To this end, the study proposes the development of an Integrated Strategy for the Development of Coal Mining (ISDCM).The model is based on the public and private partnership arrangement that would alleviate most of the prevailing constraints when implemented. The model would furthermore have the capacity to rectify most of the existing constraints. It would be funded from the commercial sector and would operate on triple bottom lines of economic, social and environmental factors, with equal weight. This is a desirable direction for the future in order to maintain sustainable development. Emanating from the study are policy and research recommendations for the South African coal mining industry, covering the coordination of the critical areas of the proposed integrated strategy for the development of the coal mining industry. Such recommendations include further research into new coal mines and power stations as well as perceptions and expectations of potential investors in the industry, among others.

Thesis (M.A.)--Slippery Rock University, 2002. / Title from screen. Includes bibliographical references.

Surface coal mining leads to inevitable changes and notable impact on the physical environment of the earth and engenders immense damage to the landscape and the ecological environment. The dramatic high-speed rock digging and disturbance unavoidably causes ecosystem degradation and destruction. Detecting how surface coal mining affects the environment on the process of land use/cover change is one of the primary concerns to preserve nature and minimize the environmental impacts. Therefore, monitoring and understanding the environmental impact processes in mining areas is critical for sustainable management of the Earth's environment. In this thesis, remote sensing and Geographic Information System (GIS) are applied to assess the spatial environmental impact caused by surface coal mining in southwestern Indiana. The goal of this research is to develop a methodology to classify the coal mining field using satellite imagery and to quantify and assess land use /cover changes using remote sensing and GIS. The specific methods include classification of Landsat Thermal Mapper (TM) data and comparison of the spatial patterns of the classification results in the study region. The results are presented with a 3-D model to better understand and visualize the coal mining effects on the landscape. Results obtained in this study indicate the change area of land use/cover and the potential area for planting crops in southwestern Indiana. Based on the observation of the data results, vegetation in the study area was found to have changed significantly over the study period. In particular, the developed areas have been increasing quickly and the areas of agriculture and forests have been decreasing appreciably. / Department of Geography