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It may at first sight appear somewhat presumptuous for the writer to attempt to discuss a subject in which he cannot pretend to possess any special scientific training; but a sufficient apology can surely be found in the fact that a very large percentage of the accidents from explosives occurring in metalliferous mines is traceable to the ignorance of the characteristics of these compounds by the miners who have to handle them, and to their deliberate disobedience of the rules laid down for their guidance by the manufacturers, the government regulations, or the special rules of the mines.The only method which promises any possibility of improvement upon these conditions is to substitute reason and understanding for the rule-of-thumb principle which says "you should do this" or "you should not do that." In the one case his own knowledge and intelligence enables the miner to avoid any dangerous practice in the other his inclination prompts him to do anything which will save time, provided he is not found out or at best trusting to his memory to tell him what is dangerous, without the reasoning which makes that memory easy.Another evil of rule-of-thumb knowledge is that, from its very nature, it prevents adaptability, and so we find that old miners, who learnt blasting in the days of black powder, cannot understand why high explosives do not require heavy tamping, or because copper bars are permitted in tamping powder they should not be used with other explosives...

Jan 1, 1903

As a result of the rapid economic growth in Japan, environmental problems have become a national concern in the latter half of the In 1967, the Basic Lair for Environmental Pollution Control was enacted as a fundamental ::olicy in this field. This lair provided compre- hensive guidelines for the action to be taken pollution prevention. The biggest problem n air pollution of those days was that of the sulphur dioxide content of the atmosphere. Based upon the law, the smelters in Japan have struggled hard to solve this difficult problem. Consequently, the ambient SO2 level has been lowered gradually year by year. At present, the ambient SO2 level is nearly equal to that in the atmospheric background. Furthermore, the fixation ratio of sulphur in Japanese copper smelters has attained up to 99.5 per cent.

Jan 1, 1980

A standard practice of auditing mill designs has developed in the mining industry. The purported aim of this task is to ensure that the mill being offered conforms to the design specification, thus reducing the purchaserÆs risk. However, careful examination of the auditing methods used in the past shows that this is not the case. In some cases, what auditors have been providing is effectively a quality assurance check of the input data, not a full independent audit of the vendorÆs design. It will be shown that these past auditing methods have contributed to the stagnation of mill specification development. This lack of specification improvement combined with the current trend towards increased allowable fatigue stress ranges can result in an increase in risk for the purchaser.

Jan 1, 2002

By Fabjanczyk M. W

Artificial ground support has developed into a refined science over the past 20 years. From reactive support systems such as timber props and steel supports, to active systems such as roof bolts and cable anchors, ground support technology has now developed efficient systems that work well in many instances. However this paper demonstrates that there is still a long way to go to develop optimum ground support systems. Some conventional rock bolts and cable anchors emphasise their tensile capacity only, without considering other factors such as their shear strength or shear modulus, or if the support member can transfer all of its support capacity to the surrounding rock. Examples are given of the use of ground anchors with high tensile and shear capacity in underground coal mining as well as examples of slope failures in open pits where the cable bolts have remained intact because they have been unable to transfer their full capacity to the surrounding weak rock mass. For underground coal mines, speed of installation is also of primary concern, but it must also have high tensile and shear capacity both in terms of strength and stiffness. Ground support systems of the future must therefore address these problems. An innovative new rock bolt is discussed which goes some way towards solving these problems. This new rock bolt is screwed into the rock and thus has a direct mechanical interlock with the rock. Initial field results show that it has an extremely high anchor capacity and can be fully installed in approximately 30 seconds. It has considerable capacity to improve the productivity of the coal mining industry.

Jan 1, 1992

The smelting operation associated with the production of aluminium has a voracious appetite for high grade carbon materials. Within the technical parameters of the Hall-Heroult process, the reduction of alumina to one tonne of aluminium results in the consumption of nearly 0.5 tonne of carbon at the anode of an electrolytic cell. This paper reviews the role of carbon and the basic quality requirements of carbon products in the production of aluminium, discusses the effects of certain physical and chemical specifications on smelting and related operations, and examines recent trends in the quality of these raw materials.

Jan 1, 1977

By Hammond J. R, Ward T. A

The Tom Price orebody, in the Hamersley Ranges of North West of Western Australia, is mined by Hamersley Iron Pty. Limited. The orebody is a folded sequence of hematite and shale bands capped with goethite, with a con- sequential variable iron content. The overall grade is below that required to yield spec- ification product, necessitating selective mining, 'Zone Plans' based on geological structure have been developed to yield forward information on material types and grades. Short and medium term mine plans - the initial stage of quality control - are based upon these 'zone plans'. Blasts are laid out to break to the grade boundaries, thus minimising dilution, and the samples taken from the blasthole cuttings provide blast grades. Blending of shovel out- put from different blasts forms the operational basis of grade control. Shales, being more friable than hematite, produce fines that are lower in iron grade than lump. Quality control in the mine centres around maintaining the target fines grade, compensation being applied in the mine if the fines grade lies outside the target range.

Jan 1, 1973

This paper is a summary of the general theory of sampling published by the author in 1975. Sampling is a random process and its the- ory is a study of the, numerous errors liable to take place in the course of its realization. A complete sampling scheme is a sequence of sampling (proper) and preparation stages . At each stage, the total error ET is the sum of : -.Sampling errors EE arising from the selection process itself. -Preparation errors EZ arising from the operations (crushing, transfer...) sup- ported by the sampled material. ET a EE + EZ . At each sampling stage, the (total) sampling error EE is the sum of seven inde- pendent errors : - Weighting error ED resulting from the non-uniformity of the density or rate-of-flow of the sampled material. - Integration error EI1 resulting from the long-range distribution heterogeneity of the sampled material. - Periodicity error EI3 resulting even- tually from periodic quality variations of the sampled material.

Jan 1, 1976

The preconcentration of uranium ore by radiometric ore sorting at Mary Kathleen Uranium Ltd. is described. The operation of the ore sorting machines is discussed in detail and performance results obtained with the existing system are presented.

Jan 1, 1978

By Ogilvie M

South Bulli is the oldest and largest underground coal mine in Australia. Two longwall units are in operation and current production is 2.5 to 3 million tonnes of run of mine product per year with a workforce of 600. Prior to 1984 a workforce of around 1,200 produced 1.5 million tonnes. Advances in technology can. of course, account for some of this gain, but the changes made in the human resources area are also seen as playing a major role in South Bulli emerging as a reasonably stable operation.The human resources strategy adopted recognises the value of the workforce and is aimed at not only fostering cooperation as all levels, but also making employees aware of the direct contribution they can make to the success of the enterprise.

Jan 1, 1991

Evolutionary changes to the original sizer concept are mild when compared to those which have taken place in the engineering standards embodied in today's commercially available machines. This paper examines the principles of sizer operation and reviews the development trends in new applications for this unique screen type.

Jan 1, 1978

By Durucan S

Uncertainty due to spatial and temporal variability of different pollutants found in soil, water and air is an important issue in the modelling of environmental impacts. Recognition of spatial environmental patterns is relatively straightforward to achieve by applying most of the well-known artificial neural networks or adopting a stochastic approach. However, it is the temporal component of the environmental variables that makes modelling of the environmental pollutants particularly complicated and challenging. This paper presents the results of a case study investigating the artificial neural network performance when modelling the spatio-temporal behaviour of environmental pollutants. The test case involved the modelling and prediction of the distribution of water quality indicators along a river from the point of discharge of treated mine effluents. The behaviour of river water quality indicators is rather complex and shows a lot of fluctuations due to a number of hydrochemical, hydrobiological and hydrodynamic factors. Results obtained in this study indicate that artificial neural networks provide a very powerful and robust method for simultaneous modelling of spatio-temporal behaviour of environmental pollutants.

Jan 1, 1995

By W Stange

Assessing the risks in a mining project is a key aspect of project evaluation. This is an exacting and demanding task because of the complexity due to the need to deal with uncertainty over long time periods. The way risks are assessed and managed is critical to the long-term success of the projects and the business. Discounted cash flow (DCF) analysis is commonly used for project and risk evaluation. A discount rate is selected that accounts for uncertainties in the cash flows. However, it is difficult to determine an appropriate discount rate due to the large number of factors that need to be considered and the complex relationships between risk sources. Using a proven framework, ævalue at riskÆ (VaR), this paper proposes to rigorously model and quantify ærisk at sourceÆ. The approach was first employed to assess financial market risks and is now widely used in the banking sector for risk assessment. In project evaluation, all risk sources are identified and estimated separately to ensure the overall project risk is quantified accurately. A bottom-up approach has been proposed. Estimates are first carried out for risk factors at the bottom of the project structure. The assessment is then applied at increasingly higher levels until the overall project risk is estimated. Value at risk is a versatile methodology and can be used in a local or integrated manner. The final value is objective and the calculation steps can be easily justified and followed. Four case studies have been included to illustrate how the proposed approach can assist management in decision-making.

Jan 1, 2009

By Tonegato S, Wood M

The lack of objective data on roof bolting machines, bits, rods and overall system has created the need for an objective assessment of roof bolting. This work outlines a test rig for such objective assessment of component parts of the roof bolting system.

Jan 1, 1986

The Yilgarn Block of Western Australia presents (figure 1) a number of problems for conventional diamond exploration based on heavy indicator mineral sampling. These problems are due to the geology and unique geomorphological development of the Yilgarn Block.Essentially the Yilgarn Block is a pene- plain developed on a craton composed of Archaean intrusive granitoid rocks with meta- morphosed greenstone; which, apart from regional uplift, has not been tectonically disturbed since planation by glaciation in the Permian. Therefore since the early Plesozoic the Yilgarn Block has been subjected to terres- trial weathering conditions. Bettany et al., (1984) identify two phases of particular importance in the development of the present landforms: 1. Periods of lateritization during the Tertiary which result in the ~lassi~al laterite profile (figure 2). Duricrust indurated : Fe and Al oxides Mottled zone : Clay and Fe oxides Saprolite or pallid zone : leached clay grading into fresh rock. 2. Subsequent periods of aridity and semi- aridity during which laterite development was truncated and reworking of laterite Occurred.

Jan 1, 1988

The geology and mineral deposits of the West Pilbara Goldfield are described and comparison is made with the Pilbara Goldfield,, In the West Pilbai'a Goldfield two adjacent environments are represented by a predominantly clastic succession and a predominantly volcanic succession. These two successions are lateral equivalents and lithologically they are similar to the classical successions at Warrdiwdbna and Mosquito Creek. How- ever, no evidence of a significant erosional break has been found. It is suggested that the Archaean rocks of: the Pilbara Block represent a single geosynclinal cycle, which culminated in orogenesis, within which-local disconformities have been developed in various places: and that the sub-Mosquito; Creek unconformity at Eastern Creek may be the most widespread of these disconformities, Widespread evidence of'preconsolidation movement, aid the intrusion of igneous rock into. unconsolidated sediment, suggest that tectonism and igneous activity began at a very early stage, This was localised along lines of fracture in an unidentified basement.,.Moveme.nt was primarily vertical and persisted into the older Proterozoic, The sediments were enriched in metal by vulcanicity, chemical sedimentation, and possibly detrit`1' contribution. Diagenesis and metamorphism caused the remobòliyation of the metallic constituents of igneous and sedimentary, rocks which were then localised-in loci of dislocation-formed both before and after consolidation.,.. . . , . .

Jan 1, 1964

By T P. Hynes

Submarine tailings disposal is conceptually an attractive option for managing reactive mine wastes in coastal regions by virtue of reduced sulfide oxidation under a water cover and no infrastructure to maintain after mine closure. However, the lack of detailed knowledge of metal leaching, dispersal of fine tailings and biological impacts in the marine environment has led to no operating permits currently in effect in Canada. Detailed chemical and ecotoxicological assessments at two historic copper mine sites (Little Bay and Tilt Cove) in the north coast of Newfoundland with tailings disposed in an estuarine to shallow (=100 m) marine environment have demonstrated reduced reactivity of sulfidic tailings when submerged under water. Only non-acute toxicity is detected in biota inhabiting the immediate vicinity (A review of another historic shallow marine tailings operation in the southern tip of Vancouver Island (Jordon River) with a high-energy setting also reveals problems with unconfined tailings dispersal and temporal biological impacts. Documented studies at two deeper (140 - 360 m) marine tailings disposal operations at the northern tip of Vancouver Island (Island Copper) and northwestern coast of British Columbia (Kitsault) again illustrate imperfect predictions of tailings re-suspension and dispersal. At these sites, bioaccumulation of tailings-derived metals appears to be minimal. There is evidence of rapid re-colonisation of the tailings surface by benthos but of different species than the original population. Integrating these observations with reported metal fluxes and biological diversity associated with submarine hydrothermal vents, the risks and benefits of deep-sea (>1 km) tailings disposal are discussed. To determine if submarine tailings disposal in deep, confined basins on the seafloor is environmentally friendly, detailed multi-disciplinary research incorporating physical, chemical, biological and toxicological components will be indispensable.

Jan 1, 2003

By G D. Carman

White Rock is a reduced tungsten-tin skarn deposit near Rye Park, New South Wales. This abstract summarises the depositÆs mining and exploration history, and current exploration by Paradigm Metals Ltd targeting an economic resource at the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Lott JB, Scuffham JB

Until very recently the application of solvent extraction to. the recovery of metals has been considered only for ithose operations where no other process was available. In general, .these operations, have involved metals such as 'f uranium or the rare earths, where the value of metal recovered has been very high. As a result, the tendency has been to consider solvent extraction as a very specialised, high cost technique with minimal application in the base metal industry. Since the mid-1960's this attitude has had to be changed drastically with the development of solvents specifically designed for the selective extraction of individual metals such.ascopper. The result is that solvent extraction must now be regarded as a proven hydrometallurgical technique for the recovery of base metals, and in particular copper. The first significant event in the application of solvent extraction to base metals was the production by General M. Inc. of a compound, designated LIX-63 (R)(1), which was a specific extractant for copper from ammoniacal sns. This did not find a wide application, however, because copper solutions with a pH in the applicable range we more readily treated by conventional techniques.

Jan 1, 1970

By Moon N. T, Torrance A. C

This study has considered the effect of mechanical shock on the resilience of the glass microspheres commonly used to sensitize an explosive emulsion. The damage to the glass microspheres caused by detonating cord, emulsion manufacture and the manufacture of the glass microspheres were considered along with the effect of sensitizer concentration on explosive performance. Reductions of up to 50% in the glass microsphere concentration of an emulsion explosive can result from poor initiation practice, such as the use of high strength detonating cord as downlines during initiation. Laboratory results suggest that detonating cords of strength greater than 3.5 g/metre should not be used as this can seriously affect explosive performance, particularly in small diameter charges. This reduced performance results from damage to the sensitizer elements and recrystallization of part of the emulsion phase.

Jan 1, 1990

By Howard G. L

The gold treatment plant of Great Western Consolidated N.L. is at Bullfinch, Western Australia, 22 miles north of Southern Cross, which is 100 miles west of Kalgoorlie. A railway to Southern Cross connects the mine with the main Perth-Kalgoorlie line.The plant, which commenced operations on the 31st October, 1952, was, designed by Messrs. Alex: Stewart & Co. in consultation with the technical staff of Western Mining Corporation Ltd. to treat 1,000 long tons a day, made up of approximately equal parts of quarry oxidized ore and underground sulphide ore, by moderately coarse grinding (2-3 per cent plus 65 mesh Tyler) and straight cyanidation without straking. The design had to allow for future treatment of all sulphide ore at the rate of 40,000 tons per 28-day periodand to make provision for the possible later inclusion of preaeration treatment.The test work on .which design was based was done on representative development samples, the mine being divided into zones for this purpose, to check possible local variations from average treatment behaviour. Proposed mill feed mixtures were made up from time to time for complete ore dressing tests, which were conducted in the Western Mining Corporation laboratory at Kalgoorlie.The chief feature of the design was that the plant had to handle the extremes of very soft, poor settling and filtering oxidized ore and very hard, good settling and filtering sulphide ore. On one hand, crushers and mills had to be large enough to handle the sulphide ore and on the other, thickeners and filters had to be large enough to handle the oxidized ores.The design is marked by simplicity, the use of large units of equipment, and flexibility to cope with a variety of ores.

Jan 1, 1956