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This talk was delivered in Kalgoorlie in April this year, to the Kalgoorlie Branch of The Institution of Engineers, Australia. We believe it is of such interest to members of our Institute and readers of this publication we believe it important to extend the audience who have the opportunity to read it. An edited version follows:"Why should we be so concerned about Mining Related Education; after all is said and done, the mining industry is not a great employer of persons?"The mining industry is capital rather than labour intensive. It employs only 2.7 per cent of the national workforce. However; the minerals industry is Australia's major exporter accounting for over 40 per cent of the nation's total export of goods.In Western Australia the value of minerals production in 1985 was about $5,000 million and consequently mineral exports accounted for about 53 per cent of the total value of overseas exports from the State. The diversity of the mining industry is also worthy of mention and produces iron ore, alumina, gold, nickel and mineral sands. That apart, our potential to become a major producer of diamonds, rare earths and petroleum products is considerable, not to mention base metals (copper, lead and zinc) and uranium.Our mining industry is of national importance and contributes in excess of 30 per cent of the total value of Australian overseas trade. Although the mining ind ustry does not employ many people, the people it employs contribute very much more, per capita, to the wealth of the nation than do employees in any other sector of our economy.No-one would deny that during the 20th century Australians have depended on the export earnings from the sale of relatively unprocessed agricultural products and more recently the sale of relatively unprocessed minerals for their standard of living.Not surprisingly, therefore, our economy is highly vulnerable to unstable world commodity market prices.The slump in trade we are currently experiencing (in first quarter 1987-Edition) was brought about by the over supply of the raw materials we produce. However, the recent downturn in world market prices is more serious than previous slumps because in part it is due to technological advances 'in other countries which could have a permanent effect on the world trade of primary products.

Jan 1, 1987

This paper summarises the influence of slurry rheology on the grinding throughput of batch laboratory and continuous plant-scale mills operating in open and closed circuit configurations. The results of controlled changes in percent solids, particle size, slurry temperature, and viscosity control chemicals are demonstrated. An underlying rheological explanation of the above factors is offered which involves tying the specific rates of breakage that are occurring in the mill with the specific rheological character that the slurry is exhibiting at any given set of operating conditions. Some industrial scale operating guidelines are presented which have proven useful in increasing the net pro- duction capability of grinding circuits.

Jan 1, 1978

By W P. Darcey

Jabiru Metals completed a feasibility study on the Jaguar Base Metal Project in July 2005. The study was based on conventional truck haulage via a decline. Conveyor haulage was considered but not in sufficient detail to provide a meaningful comparison. The current study investigates the cost and productivity of alternative ore transport systems for the Jaguar project. The options considered are conventional underground truck, conveyor, road train, rigid frame truck, monorail haulage and shaft hoisting. Shaft hoisting was not considered in detail due to the high capital outlay for such a relatively short mine life of less than six years. This study goes beyond the common approach of evaluating haulage systems in isolation; it includes development costs, timing of ore production and costs associated with mine services as well as administration and milling costs. The results of this study indicate that the best haulage option for the Jaguar project is conventional truck using the Hitachi AH400 trucks. The net present value (NPV) for this option is A$8.13 million higher than the next best option namely the Kiruna E635 electric truck. The conveyor option has the lowest operating cost per tonne of ore but the longer development time negatively impacts on its NPV. The monorail option is considered impractical due to the number and length of trains required to achieve production targets.

Mar 21, 2011

By Aspinall T. O, Just G. D

Computer software systems have been developed to assist in a wide range of specific mine planning and scheduling applications. In selecting appropriate systems for any mining operation it is apparent that certain features have particular advantages for each mine site. The ideal solution to this problem is to select a range of systems which best relate to sections of each mining operation. This approach raises potential data linking difficulties where output from one system is incompatible with input requirements for other systems. A study at the University of Queensland investigated the problems related to the integration of a number of mine planning and scheduling software systems. The project used data from large scale coal strip mining operations in Central Queensland. Two major computer packages used extensively in the study were the SURPAC mine planning and XPAC mine scheduling systems. Dragline and truck and shovel operations were analysed in the project. Results of the work have been directly applied at the mine site to assist current strip design by effectively automating the design procedure. This enabled sensitivity studies to determine the effects of changing dragline working levels and varying pit dimensions. Coal blending studies and procedures to optimise operations have been investigated using linear programming within a spreadsheet software application. Output from the SURPAC and XPAC programs was directly linked to the linear program for this analysis. The simulation program GPSS/PC was also used in a similar manner to assess optimisation parameters.

Jan 1, 1992

By Rosenblatt M, Gilroy J. A C Cunningham C V B

Vaal Reefs Exploration and Mining Company Limited operates one of the largest producing gold mines in the world. The annual production of 76 tons of gold from 12 million tons of ore treated is obtained mainly from underground sources. Daily some 6.6 km of stope face is blasted and 41 tons of explosives is used to break the rock. The mine employs 45 000 men of whom 35 000 work underground. The company operates nine large vertical shaft systems of which seven extend more than 2000 m below surface and an eighth, currently being sunk, will bottom at 3700 m below surface.

Jan 1, 1995

By Crawford G. R, Wold M. B

The application of the hydraulic fracturing technique to the measurement of in situ rock stress from underground excavation is discussed; including relevant theoretical considerations, equipmenl details, experimental technique and analysis procedures. Examples of the application of the technique at three Australian coal and metalliferous mining operations are given. The results obtained from these applications are compared with corresponding results obtained from overcoring tests conducted in close proximity at each site. Generally good correspondence in a wide variety of rock types is indicated. Experience gained with hydraulic fracturing at several underground mining sites has indicated it to be a quick, cost effective means of gaining an understanding of the in situ stress field in sufficient detail for many mine planning functions.

Jan 1, 1990

By J W. Lee, E Baafi, N Aziz

Ground subsidence due to mining is a common dilemma confronting the underground coal mining industry. The effects of underground longwall mining on river valleys have come under scrutiny, especially when mining is located underneath catchment areas. As public awareness of mining impacts on the environment increases, there is the need to develop damage mitigation strategies. Results of numerical modelling show that river valley response to underground longwall mining can be simulated and evaluated.

Jan 1, 2005

By W L. Daniels, C Stilson, C Zimmerman

Mineral sands mining for ilmenite, rutile and zircon has disturbed over 1000 ha of prime farmland in Virginia (USA) since 1997 and additional areas are likely to be disturbed in Virginia and North Carolina (USA) over the next 15 years. Full-scale mining operations at the Old Hickory Project in Virginia were initiated in 1997 by Iluka Resources Inc. and restoration protocols have continued to evolve in response to a variety of economic, technical and social issues. Early on, the return of these lands to agricultural row-crop production was complicated by vertical stratification of tails + slimes and lateral variability in soil physical conditions in the reclaimed pits and by limited topsoil return. Virginia Tech and Iluka have worked cooperatively with all stakeholders for over 20 years to review the pre-existing research base, conduct new and innovative site-specific research and thereby provide reasonable expectations of post-mining soil productivity levels. In 2004, Virginia Tech, Iluka Resources and a local leaseholder (Carraway-Winn family) agreed to jointly manage a 45 ha research demonstration farm where the long-term effects of alternative soil reconstruction practices are being rigorously monitored for both row crops (corn and wheat) and forage production. All mined land crop yields are also compared to an adjacent undisturbed exceptional quality prime farmland soil. Row crop yields between 2005 and 2010 were significantly above county average yields (regulatory target level) and approximately 75 - 80 per cent of undisturbed adjacent prime farmlands. The state regulatory authority has recently relaxed its position on the necessity of topsoil return versus use of topsoil substitutes based on appropriate on-site research results and the ability of the reclaimed soils to meet comparative local county crop yield targets. This cooperative effort allows all clientele groups to objectively assess the post-mining productivity of these mined lands while providing an invaluable educational opportunity for the mining industry. CITATION:Daniels, W L, Stilson, C and Zimmerman, C, 2012. Development of effective rehabilitation protocols for mineral sands mining in Virginia, USA, in Proceedings Life-of-Mine 2012 , pp 97-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By Stevenson BG

The relevance of ore-dressing mineralogical investigations to developing and improving metallurgical flow-sheets is discussed and examples are given of the application of such studies to various types of ores and mill products (Au, Cu-Sn, Ni and Sn). The mineralogical investigations described illustrate (a) assessment of the feasibility of ore pre-concentration by heavy-media cyclone separation, (b) evaluation of the potential applicability of various metallurgical treatment processes to an ore, and (c) characterization of mill products to assess circuit efficiency and to guide circuit modifications.

Jan 1, 1978

The preamble to the mining Act sets out that such Act is to provide for the encouragement and regulation of mining within the State of Queensland. This paper will attempt to follow the legislative path of such aim and in particular to show what part Mining Wardens play in the administration of the Mining Act.The Mining Act empowers the Governor in Council to constitute Mining Districts and Mining Fields and to appoint any duly qualified officer of the Public Service of Queensland to be a Warden or a Mining Registrar. As a matter of practice Stipendiary Magistrates who hold office in the major centre within a Mining District are appointed Wardens and Clerks of the Court are appointed Mining Registrars. In some districts where there is no Stipendiary Magistrate the Clerk of the Court is appointed an Acting Warden with all the powers of a Warden. Every Warden so appointed is a Warden for the whole State.To achieve impartiality Section 74 of the Mining Act provides that a Warden shall not hold or be entitled (directly or indirectly) to the benefits of any share or interest in a mining tenement or mining venture and provides a penalty of $1000 or imprisonment for six months or both, for contravention of such section.

Jan 1, 1986

By L Thorburn

In 2009, the Queensland Government developed a series of amendments to environmental authorities (EAs) for mines throughout the Fitzroy Basin in response to studies that assessed the cumulative impacts of mine water discharges in the basin. One of the key amendments was the requirement for all mines in the Fitzroy Basin to develop and implement a receiving environment monitoring program (REMP). The intent of the REMPs was to provide baseline information on the condition of the receiving environments of the mines and any impacts resulting from release of mine-affected water. Since this time, the requirement to complete a REMP has been incorporated into new or revised EAs for mines (including metalliferous mines) in other regions, as well as for other industries that discharge to natural watercourses (such as coal seam gas). This paper discusses the approaches that can be used to incorporate biological monitoring and direct toxicity assessments into REMPs. It highlights the importance of collecting biological data using sound experimental design principles to investigate whether releases resulted in environmental harm; and the use of monitoring data, coupled with direct toxicity assessments, for setting more realistic, site-specific trigger values and release limits (compared to the default guidelines such as Australian and New Zealand Environment and Conservation Council (ANZECC), which may not be appropriate to the region). Implementation of a robust REMP can maximise outcomes for both the proponents and the environment.CITATION:Thorburn, L, 2013. Receiving environment monitoring programs - making the most out of biological indicators and direct toxicity assessments for monitoring of aquatic ecosystems, in Proceedings Water in Mining 2013 , pp 143-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

A description is given of a detailed examination of a coal bore core and of attempts to predict properties of equivalent "as-mined" coal using the bore core data so obtained. The accuracy of the prediction was measured by testing independently a large sample of coal which was produced under near mining conditions from a site adjacent to the bore core. Very encouraging results were obtained particularly in the prediction of size and ash distributions and washability characteristics of run-of-mine Coal.

Jan 1, 1972

By A Hall, D Kratochvil, P Littlejohn

Economic recovery of gold from complex gold ores, including poly-metallic deposits, is impacted by the presence of cyanide-soluble base metals. These base metals can create both a metallurgical challenge plus waste handling and disposal challenges. Base metals such as Cu and Zn compete for the cyanide reagent and often increase the total cyanide consumption to the point of making precious metals recovery uneconomic. In addition, the accumulation of base metals in cyanide solutions represent a challenge for cyanide detoxification and waste water treatment as these metals report to waste sludge. Such sludge requires safe handling and disposal, with possible long-term liabilities.Base metal interference can be removed with sulfidisation-acidification-recycling-thickening (SART) process technology. SART liberates the base metal from the cyanide complex and precipitates the metal as an insoluble sulfide product that can be recovered as a commercial grade concentrate. With the base metal precipitated, the cyanide can be regenerated as free cyanide and recycled to the gold extraction circuit.BioteQ completed laboratory testing for two projects, one employing cyanide leaching of copper-gold sulfide flotation concentrate and one employing a Merrill Crowe process, to determine the effectiveness of SART to remove and recover Cu and Zn in high-grade sulfide concentrates and to reduce the impact of cyanide-soluble metals on gold recovery and cyanide consumption. This paper will provide an overview of the testing methodology and results along with a review of the potential for SART to be applied to complex gold ores with poly-metallic deposits to improve project economics, operability and waste management.CITATION:Littlejohn, P, Kratochvil, D and Hall, A, 2013. Sulfidisation-acidification-recycling-thickening (SART) for complex gold ores, in Proceedings World Gold 2013 , pp 149-156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By S Zheng, Y Zhang, Z Wen, S Ma

Red mud (RM) is a solid waste product generated during alumina refinery process, and is usually stored in SFs (SFs) because it canÆt be disposed of easily. In this paper, environment degradation caused by RM-SFs was systematically assessed by the method of single factor pollution index based on the analysis data of water, soil and atmosphere sampled around one newly-built and one decommissioned RM-SFs, which are managed by an alumina production company in China. The results revealed that the ambient environment around RM-SFs is seriously polluted by alkali and mercury (Hg). The pH value of RM leachate, surrounding surface water and groundwater are all higher than the limit of water quality standards in China. And as a possible result of overflowing of high alkaline leachate, soil pH value for the decommissioned SF decreases with increasing distance between the sample collection points and the closest side of RM storage facility (RM-SF). Total Hg concentrations in RM leachate, surrounding surface water and groundwater all exceed Grade III limits of ChinaÆs Environment Quality Standards for Surface Water and Groundwater. However, the air quality was little affected as the daily average of TSP in the air is below grade II values of Chinese Ambient Air Quality Standard.CITATION :Wen, Z, Ma, S, Zheng, S and Zhang, Y, 2012. Assessment of environmental quality impacts caused by red mud storage facilities in China, in Proceedings Life-of-Mine 2012, pp 51-58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

The development of present methods of pillar extraction has evolved from the very earliest of hand mining operations which were limited in scope by venti- lation and transport considerations. Conservation and safety considerations also have led to the current shortwall operations with conventional equipment and powered supports. The shortwall methods have had significant effects on safety, costs, con- servation, flexibility, and other aspects of pillar extraction. The present stage falls short of the ideal but is some guide to prediction in what direction may lie the ideal methods for the future.

Jan 1, 1974

Coal mining legislation makes frequent reference to æSafety Management SystemsÆ but there is a chronic shortage of useful guidance material as to how these might be applied to hazardous exposures. Several studies have indicated that for each death that is reported as a result of an industrial æaccidentÆ, there are five deaths that caused by occupational exposures. Because the deaths from occupational exposures do not occur on site and often well after employment has ceased, they are generally unreported. Improved access to mortality data from coroners, the Australian Institute of Health and Welfare and superannuation service providers (early claims from death and total permanent disability), has given rise to some analysis of death and disability data that provides evidence that there are emerging opportunities to develop and improve safety management systems for hazardous occupational exposures. Issues explored include how safety management systems might be developed in relation to dusts and chemicals and other hazardous exposures to ensure the risk of disorders with long latency periods are reliably assessed and the exposures effectively managed. The current standards and guidelines which refer to safety management systems in general or to management of exposure related hazards are examined. Many standards are based on dose-response studies that provide for an acceptable percentage of workers to suffer adverse health outcomes. An alternative management system might be to apply dose-response relations to health surveillance to identify æat riskÆ individuals and effectively manage health and related safety risk at an early stage.

Jan 1, 2005

Process variables in flotation circuits are outlined with a view to producing mathematical models of circuits. The nature of the kinetics of flotation are discussed and the effect of process variables on the kinetics considered. An approach for a possible model is briefly outlined.

Jan 1, 1971

By burgess F, Manlapig E. V, Franzidis J. P

Bubble surface area flux, a parameter which is determined by bubble size and superficial gas velocity, has been identified as a criterion for flotation scale-up from a metallurgical point of view. Investigations at Hellyer, Scuddles and Mt Isa

Jan 1, 1997

By Brown N. R

This paper attempts to highlight some of the problems encountered in the economic exploitation of the deeper coal seams by opencast mining methods. The major cost elements of three methods of overburden removal are examined in relation to the overall cost of winning coal from deeper-lying coal seams. The three overburden removal methods examined are dragline stripping and two systems combining dragline stripping with shovels and trucks at varying depths of overburden. A dragline is, undoubtedly, the most cost effective system of overburden removal for depths of up to 30 metres but it is suggested that, when dealing with incremental overburden depths in excess of 30 metres, engineers should consider carefully the possibility of using a shovel and truck operation, or other system, to augment the use of a dragline.

Jan 1, 1986

By Mikula PA

This paper presents the results of in-situ and laboratory investigations into a mining method which utilises conventional continuous mining techniques to carry out two passes in thick coal seams, resulting in the development of stable pillars with relatively small width dimensions and heights up to 6 m. Geotechnical investigations included structural mapping, brightness logging and standard laboratory testing. Virgin stress was measured using overcoring techniques. Two approaches to pillar design were used in the study. These were; pillar design based on empirical formulae and laboratory testing, and pillar disign using calibrated mathematical models. A trial panel was developed at 300 m depth to study pillar deformation and stress changes due to mining. The extent of rib deformation was studied using borescopes and extensometers. In-situ geotechnical measurements were used to calibrate displacement discontinuity and finite element mathematical models of the coal seam. These models were then used to predict the behaviour of a small panel of pillars which were to be developed to 6 m height. The mining method was shown to be feasible provided adequate rib support was installed. The benefit of rib support was found to be two-fold, in that it increased confinement of the pillar in zones of low horizontal stress, while reducing horizontal stress relaxation in zones of high horizontal virgin stress. The possiblity of roof control by designing the small pillars to yield on retreat is discussed.

Jan 1, 1986