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This paper outlines the aims, objectives and means by which a life of mine land use plan was established for Comalco's bauxite mine at Weipa. Comalco realises the need to strategically plan for future mining activities and still minimise the impact of operations on the natural resources of the region. With this realisation long-term forward planning has been implemented to improve the Company's ability to select future sites for mining, industrial use, agriculture, town expansion and conservation purposes.The knowledge of mineral, water, soil and animal resources has expanded dramatically in the past decade. During 1990 Cornalco purchased Geographic Information System technology which has allowed previously collected resource data to be presented in map form. These maps as part of the Life of Mine Land Use Plan are both information based and strategic which can be efficiently updated. The maps allow a broad audience from engineers, geologists, environmental scientists and site managers to government officers and the general public to comprehensively view and scrutinise the operations.

Jan 1, 1992

Utah's Blackwater mine began operations in 1967. The four CQCA mines controlled by Utah followed over the period 1971 to 1979. Project feasibility studies for all these were based on open cut mining to overburden depths of 60 metres, with typical project lives of 12 to 16 years, depending on reserves Further studies, initiated after the mines had started, showed that continuation of open cut mining beyond the 60 metre highwall was viable. In 1973, the Deep Stripping Project (DSP) was launched to define the scope for stripping deeper, to determine what the additional equipment needs might be, and to pu forward proposals for a full scale trial system. The project commenced at grass roots with a literature survey, proceeded through a sequence of equipment evaluation, specification, design and manufacture to the commissioning of the Goonyella BWE system. Studies are continuing to assess the future deep stripping requirements for all Utah's Bowen Basin mines.

Jan 1, 1983

By Ainslie LC, Toens PD, Andreoli MAG

The geological and economic aspects of the known deposits of uranium in southern Africa are described. Processes influencing uranium mineralisation in the relevant geological environments are elaborated upon in order to define fundamental characteristics of mineralisation in the sub-continent and identify potential areas for the location of new deposits. Several areas, namely the Damara orogenic belt and its extension in Zambia and Zaire, the Bushveld zone, and the terrains of uranium fertilisation from the mantle have a high probability of hosting uranium deposits which are yet to be discovered. Uranium resources of the southern African region have been estimated and production forecasted to the year 2000. This geographic region contains one quarter of WOCA's resources in the Reasonably Assured Resources and Estimated Additional Resources - Category I exploitable at less than 130/kg U. On this resource base, it has the potential to maintain its position as the leading exporter of uranium in the world with a production of 13 350 t U308 by the end of the century. Zambia and Zaire are expected to join South Africa and Namibia as uranium producers in the next decade, with their combined share of projected production being in the order of 10%.

Jan 1, 1986

Heavy medium separation is widely used because of the precision of separation achievable and the flexibility of control. Good design is manifest in the eventual achievement of the operational objectives. These objectives which take account of the assessed quality of raw feed, market requirements and production cost levels need to be carefully prepared and realistic.

Jan 1, 1987

By Fyodorov A. N, Sorokin M. L, Komkov A. A

The Vanyukov Process is a bath smelting technology, that has been investigated for over 25 years and since 1977 has been in use on an industrial scale. Results of trials that have been carried out at the various pilot facilities over the past 15 years are considered in this paper. Both the main process aspects, design of the pilot furnaces and metal distributions are presented for consideration. Experience of the smelting of copper, copper-nickel, copper-zinc, nickel, lead, and pyrite concentrates is analysed.

Jan 1, 1992

The excessively high cost of production in underground coal mines has made the survival of many coal mines around the globe economically non-viable. The global competitive coal market speaks itself of the desirability of a lower operating cost in conjunction with a higher productivity performance, particularly in underground coal mines, and calls for an optimal production planning under a host of constraints. Such a task of optimal planning is not an easy exercise like that of traditional planning based merely on intuition, experience and subjective judgement. It essentially demands a thorough understanding of the complex interaction of mine sub-systems for judicious application of optimisation tools and techniques available with operations research. A few large mines around the globe have made an effective use of a sizeable number of operations research packaged programs for optimal decision-making (Grayson, 1989). The success of practical applications of operations research techniques made in a variety of mining problems in large mines in different parts of the world will hopefully make inroads to smaller mines in years to come. The present paper is an addition in the series of such applications of operations research tools to mining problems, particularly with reference to an underground coal mine in India. The paper is based on research work (Jawed, 1990) and deals with the development and use of a mathematical model for production planning in underground coal mines under multiple objective environment subject to a host of constraints.

Jan 1, 1995

By Callcott R

Prediction of raw coal size distributions and those generated by processing are examined using spreadsheets and the matrix analysis of breakage processes. Run of mine coal size distributions are predicted from the lithotype properties using a

Jan 1, 1998

By G W. Wilson, C Panidis

Potentially acid forming (PAF) waste rock contained in dumps formed as a result of open cut mining of metalliferous orebodies are conventionally sealed or covered using a near-saturated, low permeability compacted clay layer, protected with a mulch layer and/or vegetated growth medium. The purpose of the compacted clay layer is to limit oxygen diffusion and the infiltration of rainfall into the dump. Where the aerial extent of the PAF waste rock dump is large, or where suitable clayey material is in short supply, it may be difficult to source sufficient suitable clayey material to form the cover. The paper describes a laboratory-based investigation of combining inert waste rock and tailings to form an alternative seal or cover material. The inert waste rock was sourced from the trafficked surface of a non-acid forming (NAF) waste rock dump, with a maximum particle size of about 100 mm. This was combined with NAF thickener underflow tailings slurry in various mass ratios, and the resulting mixtures tested for their particle size distribution, compaction characteristics, soil water characteristics (relationship between suction and volumetric moisture content), and saturated hydraulic conductivity. The mixtures tested ranged in consistency from those dry enough to be compactable, to those with the consistency of wet concrete that lend themselves to placement without the need for compaction. The laboratory test results showed that the suitability of the mixtures as seal or cover materials is very dependent on the particle size distribution of the mixture, with well-graded mixtures having substantial fines performing best.

Jan 1, 2003

By S C. Goel

The Obuasi Mine in Ghana, West Africa is the largest producing gold mine in Africa, outside South Africa. The mine has changed from a mine producing from narrow vein, high grade quartz orebodies to a mine producing from wide, lower grade sulphide rebodies. Traditionally mining methods were cut and fill and sublevel caving. Now the preferred stoping methodologyis long hole open stoping. Transverse or longitudinal methods are both used, dependent on the orebody characteristics. The change has been technically, socially, economically and politicallychallenging and at times has tested the abilities of those responsible for the operation of the mine. However, the benefits have been many. Safety has improved significantly, ounces from underground have doubled. Productivityhas doubled and underground unit costs have reduced bya third. These achievements have allowed the Obuasi mine to staycompetiti ve in this time of falling gold price. During 1999 and 2000 a full review of the mining and processing operations was undertaken, and as a result, the mine is now in a phase of restructure. Efforts are being made across the mine to improve efficiencies and to reduce costs. The future for the Obuasi Mine is an exciting one.

Jan 1, 2000

By N G. Corner

A sea bed sampling programme by CRA Exploration Pty Limited over an area of 12 000 km offshore from Westland, Southland and Otago, New Zealand, led to the discovery of the Harvester Prospect, an area of some 67 km2 which averaged 189 mg/m3 gold in surface samples. This area was in water depths of 70 to 106 m and contained a high grade core of 33 km2 which averaged 283 mg/m3 gold. The gold recovered was fine grained, averaging 124 microns, and indicated a potential resource of approximately 10 t of gold per metre of thickness. Interpretation of existing seismic and geological data suggested that the gold anomaly may be associated with a unit of sediments 10 - 40 m thick, probably deposited during a lower sea level stand. Two initial attempts at vibrocoring the anomaly produced inconclusive results. In 1989 a much more powerful vibrocorer with scaled up support facilities and a dedicated 24 h turnaround laboratory were employed. The final results clearly showed that the gold was from an uneconomic surface enrichment.

Jan 1, 1990

By I Thin, I Sheppard

Resin encapsulated rock bolting practices have been adopted by Mount Isa Mines since the early-1980s. Fully encapsulated rock bolt systems meet designated requirements for long-term ground support in the mines. A variety of rock bolts, resins and installation methods have been utilised over this period in underground mining. As a parallel to this evolving application, Mount Isa Mines have tested various resin encapsulated rock bolt systems. Testing has included routine underground pull testing and the development and implementation of the push test for the entire encapsulated bolt length. The latter test enables a greater understanding and representation to be had of the overall mixing, level of encapsulation and capacity of the system. Rock mechanics at Mount Isa Mines undertake evaluation of new bolt systems that become available, in addition to the maintenance of compliance with quality control measures for the existing systems. Improved methods of installation and systems are also investigated to further the cost-effective nature and minimise risks associated with resin rock bolt practices.

Jan 1, 2002

By Corner NG

A sea bed sampling programme by CRA Exploration Pty. Limited over an area of 12000 km offshore from Westland, Southland and Otago, New Zealand, led to the discovery of the Harvester Prospect, an area of some 67 km2 which averaged 189 mg/m3 gold in surface samples. This area was in water depths of 70 to 100 m and contained a high grade core of 33 km2 which averaged 283 mghn3 gold. The gold recovered was fine grained, averaging 124 microns, and indicated a potential resource of approximately 10 t of gold per metre of thickness. Interpretation of existing seismic and geological data suggested that the gold anomaly may be associated with a unit of sediments 10-40 m thick, probably deposited during a lower sea level stand. Two initial attempts at vibrocoring the anomaly produced inconclusive results. In 1989 a much more powerful vibrocorer with scaled up support facilities and a dedicated 24 It turnaround laboratory were employed. The final results clearly showed that the gold was from an uneconomic surface enrichment.

Jan 1, 1990

Inefficient conveyors suffer carryback, leading to the build-up of materials on idlers, and other expensive components. They spill and leak material at loading zones and transfer points, causing accumulations that can damage the belt, wear moving components, and increase both cleanup labor and maintenance expense. They wander or mistrack, spilling material and en- dangering personnel and conveyor components, including the belt itself. And through these inefficiencies, they multiply an operation's hidden costs-the dollars lost because of missed production, of increased downtime, of the expense for the replacement of prematurely worn or damaged equipment. In this paper, the author will examine the importance of belt conveyors to mines and process plants He will trace the state-of-the-art in systems for cleaning belts, and controlling the release of fugitive material from conveyor transfer points, by exploring the roots of the problems, and demonstrating solutions that have been proven to be effective. Included in these systems to improve material handling are transfer point stabilization and sealing systems, dual belt cleaning systems, and belt training idlers.

Jan 1, 1991

By Tinto R

Aims of the Forum A contribution from Dr Robin Batterham, Vice President, RIO TINTO Research & Technology and a member of The AusIMM Standing Technology Advisory Qroup. Dr Robin Batterham is of view that the inevitability of automation in the minerals industry and the importance of addressing the human implications. He also outlined Rio Tinto's approach to automation. The progressive introduction of automation into mining operations will be revolutionary in its effects. This is the experience in other industries and it will be no different in mining. Mining companies most successful at implementing the new technologies will gain relative competitive advantage and those manufacturers who produce the most desirable automated equipment for miners will also gain market share.

Jan 1, 1997

In the exploration of an area proposed for the establishment of an underground colliery, consideration of all land and mining titles and consents has early priority. Environmental aspects have become more meaningful. Preliminary assessments of previous geological knowledge, together with new geological and geophysical data from surface investigations, condition the decision to proceed with costly diamond drilling programmes. Methods other than fully cored diamond drilling have a useful application in appropriate circumstances. Drilling exploration is conducted in stages of increasing density of-hole spacing to the point where, with holes at 1 km centres, reserves are categorized as measured. The programme is subject to constant review in the light of market changes.

Jan 1, 1976

This paper addresses; land use, rehabilitation and the State/Federal regulatory process, in light of Australia signing various international conventions and agreements in the area of environmental protection. The conventions on biological diversity, climate change and the implications of the Rio and Agenda 21 declarations are examined. The implementation of these initiatives through the Inter-Governmental Agreement on the Environment, and through legistlative mechanisms at Federal and State level is explored.Particular attention is given to the biodiversity strategy in context of the need to integrate economic aspirations and environmental concerns as a basis for sustsainable development. The paper concludes with a brief comparison of the major approval processes in each State, relating to mining environmental issues.

Jan 1, 1992

By Forster G, Datta P. K

Many high temperature industrial processes involve gaseous halogen-bearing environments. Essentially, these fall into three subject areas: power generation, waste incineration and especially extractive metallurgy. Fundamental to any understanding of the process chemistry and efficiency in the process technology is an adequate knowledge of background thermodynamics relating to metal-chlorine reactions. In this context, existing free energy/temperature diagrams for metal chlorides do not include many elements, in particular the so called refractory elements from Group V and Group VI of the Periodic Table, namely niobium, tantalum and vanadium, and molybdenum. This paper reports estimation and calculations of the free energy values for these chlorides. The data is discussed in the context of high temperature chlorination processes.

Jan 1, 1991

As a society, the retiring age of workers is increasing. Individuals are having to consider working to an older age (beyond 55 years), the reason being to æpay offÆ debt, maintain a quality of life or, as a bigger picture, because society simply cannot afford the aging population. The Government is encouraging and promoting those approaching retirement to work to an older age to alleviate the financial burden of an aging population. In a working context those aged 55 years and over accounted for ten per cent of the Australian workforce in 1998 with this age group expected to account for half of the growth in the workforce between now and 2016. For the 60 - 64 years which account for less than three per cent in 1998, this group is expected to account for 15 per cent of the growth in the same period. As a result of individuals who have worked all their lives and in some cases æphysically hardÆ, they do not fully enjoy their years of retirement as a time when they get to choose what they want to do rather than what they have to do. Of particular interest are the physical or health related conditions that individuals end up with and the restrictions that ensue resulting in an individual being incapacitated either physically or with respect to the state of their health.

Jan 1, 2005

When preparing an appraisal, valuation or feasibility study for a new mining project it is difficult to imagine the technical, economic, social and environmental context that the project will occupy in ten or 15 years time. This paper is about our ability to foresee the future, the choices available now in matching the project to that future context, and about the flexibility that exists in adapting the project to a changing environment. The author draws upon his experience of project reviews, valuations and feasibility studies in the mid to late 1980s in Australia and New Zealand to explore how the project context has changed since key decisions were made and what this tells us about decisions made today for future projects.

Jan 1, 2004

The papers to be presented in this Session show an interesting range of subject matter. Three discuss specific problems associated with existing mines, one deals with hydrogeological risk evaluation and one uses the impact of mine drainage on an aquifer to analyse a large-scale hydraulic parameter. Paper 1. Environment studies to determine the impacts of re-opening Banska Stiavnica-Hodrusa ore district in Czechoslovakia - Dusan Cababla - Marian Skaviniak. Future developments in established mining areas may have significant hydrogeological implications, especially where the existing mines are to be deepened. In turn this may have an impact in the area of the disposal of ever larger quantities of mine water, particularly, as is often the case, where the quality of this water is poor.

Jan 1, 1988