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The economic future of the Palmer Goldfield lies with both the gold mining and the tourist industries. An equitable solution to the competition between the two involves putting a dollar value on the historical evidence there for our Australian heritage.On 23 October 1986 the Queensland Government gazetted the Palmer River Reserves R16 of 16 200 hectares, in recognition of the competing land uses emerging in the region. The intention is that historically significant gold mining sites and relics will be preserved in situ with provision for continued gold exploration and mining.This paper explores and explains the administrative process of achieving a set of Management Guidelines for Rl6 within the Queensland political milieu. The result of that process is the achievement of some of the highest preservation standards in Australia, prohibiting surface disturbance of defined Category 1 sites, and no mining proposal has yet been refused approval.The Palmer Goldfield R16 experience is a major step in achieving a co-ordinated approach to both current mining and preservation of Queensland's mining heritage.

Jan 1, 1990

By J Palaci, M MelTndez, F Parra, I Rojas

At the Huasco Pellet Plant of Compa±fa de Aceros del Pacffico, Chile, the production of iron concentrate suitable for pellet feed from a low-grade iron ore was technically evaluated. In this study, three treating schemes including comminution, magnetic concentration and flotation in pneumatic cells were tested. The best results were obtained at the laboratory scale by flotation technique using Lilaflot D 817 M as the collector without using any depressant. The operational parameters were determined including pneumatic flotation, and three circuits, two including magnetic pre-concentration, with the low-grade iron ore. The best results were obtained by size reduction at 80 per cent under 325 Tyler mesh, three steps of magnetic concentration and three steps of flotation in pneumatic cells. The magnetic concentrate contained 63.02 per cent of iron and 6.6 per cent of silica, and after the pneumatic flotation the iron content increased up to 70.18 per cent and silica decreases to 1.07 per cent with 78.78 per cent of iron recovery at a weight recovery of 31.89 per cent. Therefore, it is possible to use low-grade iron ore to produce pellet feed from magnetic concentrates by using reverse iron flotation in pneumatic cells.

Jan 1, 2005

Expert systems have been employed in a number of areas for a considerable number of years. However, the traditional long development times associated with these systems have restricted their application. With the advent of powerful Expert System Development Tools such as COMDALE/X and the use of efficient development techniques, the time required can be drastically reduced. This results in the availability and applicability of this technology to a wide range of applications. This paper discusses some of the 'rules' which indicate amenability (or otherwise) of a particular problem to an expert system solution. Various problem types are examined and these are illustrated with reference to examples of their use at various operating sites.

Jan 1, 1991

Peraluminous metamorphic rocks may form from a variety of protoliths by a range of processes. Stratiform bodies of such rocks are relatively common in the Precambrian, but less commonly, also occur in the Phanerozoic. The protoliths of such stratiform bodies may have been regionally deposited chamosite-rich sediments, with varying amounts of clastic component, or may have resulted from the in-situ depositional or diagenetic alteration of volcaniclastic sediments, ranging in composition from rhyolite to basaltic andesite.Stratiform peraluminous metasediments, especially those of low to medium metamorphic grade, and relatively iron rich, may be genetically associated with, or be the host rocks for, a variety of styles of mineralization, especially for the ores of An, Ag, Cu, Zn and Pb.

Jan 1, 1990

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 D Hodson

Current classification of resources is entirely a subjective task. The various international reporting codes (such as the JORC Code) provide Competent Persons and practitioners with little specific guidance on the standard of work and levels of uncertainty required to classify resources into Measured, Indicated and Inferred. Furthermore, little guidance is given in the conversion of Resources to Reserves and the potential impacts on classification of uncertainties in the modifying factors. Working back from the intended use of the resource estimates, and in understanding the tolerance for uncertainty by the end user of such estimates, insights into the objective and requirements of classification can be determined. Following this approach a comprehensive set of (quantitative where possible) guidelines have been determined that will ensure resources meet the desired objective of each classification, and are consistent and comparable. The guidelines look at what is required for each step in the resource estimation process in order to ensure the final resource estimate meets the desired level of confidence. This approach provides a transparent, comprehensive, justifiable and largely objective method of classification. The implication of introducing such a guideline or approach is to highlight areas of a resource estimation that do not meet the requirements (ie drive the uncertainty beyond the objective) and then focus in on the risks that may flow on from that particular uncertainty, to mitigate or attempt to control those risks.

Jan 1, 2006

Zinc produced by pyrometallurgical processing techniques suffers the disadvantage of restricted market potential because of its impurity contents, typically lead and cadmium. Market zinc to the Special High Grade (SHG) standard can only be produced by reflux distillation refining, which is costly in terms of energy and equipment, and potentially capacity limiting. Recent published laboratory work suggested that molten salt electrorefining of zinc metal is a potentially much cheaper alternative to the reflux distillation refining. The extrapolation of the laboratory results to an industrial configuration, however, resulted in an estimated power consumption for electrorefining and associated costs offering no advantage over current reflux distillation practice. A review of this estimate now shows that a serious error in calculation was made, and that the energy consumption for the electrorefining of molten zinc would be an order of magnitude lower than that for reflux distillation refining. While this is a promising indication, further research is required before development towards an industrial scale operation is warranted. This would particularly relate to the extent to which adverse electrolyte deterioration may take place and its potential effect on the anode and cathode efficiencies of the process. This paper considers the laboratory investigations required to explore the industrial potential of the molten salt electrorefining of zinc and foreshadows some of the practical problems to be solved in further development.

Jan 1, 2000

While there is reasonable agreement on the basic chemistry of the slag fuming process, there has been an on-going debate for nearly 50 years as to the nature of the rate controlling factors in its industrial application. There have been advocates in the technical literature for thermodynamic limitations on the one hand or kinetic limitations on the other. The different viewpoints result in very different predictions as to the technical and commercial potential of the process. A resolution of the debate becomes of importance as pyrometallurgical processes are advocated as a means of extracting environmentally deleterious elements from metallurgical wastes. The present paper reviews the arguments in favour of both equilibrium and kinetic control and puts forward the view that much of the evidence for limitation of the process by kinetic factors under all conditions is unconvincing. It is maintained that the process can approach thermodynamic equilibrium under industrial conditions and that this determines the ultimate limitation on its technical performance. It is acknowledged, however, that kinetic considerations may cause the batch process to fall well short of performance predicted on thermodynamic grounds. The strong process limitation arising from the influence of chemical thermodynamics on the likely outcome of a hypothetical continuous fuming process is contrasted with optimistic forecasts resulting from the extrapolation of process models based only on kinetic considerations.

Jan 1, 2000

By D Laurence

Significant developments in future mining systems, technology and best practices are emerging that are driven by issues relating to human resources, competitiveness, environmental and social responsibility, within the dynamics of globalisation. It is proposed that the definition of the role and attributes of the mining engineer in the mine life cycle needs to be viewed more holistically in the face of increasingly more diverse and complex responsibilities. These developments are motivating the need to consider a fresh approach to mining education and training at all levels for industry. A growing diversity and complexity of professional responsibilities is extending the mining engineerÆs broadly based skill set and reinforcing the need to play a central role within increasingly interdisciplinary teams. On the other hand, the imminent new technologies that will transform the mining process are prompting the assumption that more focused and specialised skill sets will be needed. A way forward is suggested that would first define a blueprint for the future mine, as an attempt to characterise the systems architecture, processes and organisation of the next generation mine. This can be the basis for assessing the nature of the workforce and distribution of responsibilities, from which can be inferred the skills and training requirements. In the context of the mining engineer, the paper explores how understanding such future requirements will enable more proactive development of a strategy for educational development. The paper then concludes by considering issues and lessons learned from some recent mining educational development initiatives underway in Australia and Canada that are shaping significant change.

Jan 1, 2008

By M Roche, W J. Huxley

Finding a balance between practical and acceptable groundwater management, and providing for the needs and impacts of mining developments remains a challenge. The changes that accompanied the recent implementation of water reforms have provided greater flexibility for the water manager and greater certainty for the resource user. However uncertainty associated with understanding of complex aquifer systems, balanced against providing for the needs of mining developments, the rights of existing water resource users and expectations of the broader community have not diminished the conflicting issues faced by water resource managers and resource developers. Licensing under the Water Act 2000 provides the regulatory link with the taking of water for water supply purposes or as a consequence of the mining activity. This paper outlines key elements of sustainable water resource management involving certainty of access to water and adaptive environmental management that are delivered through conditioning the water licences issued for the particular mining development. Implementation of this approach is illustrated through a case study involving the BHP Billiton Cannington Mine in North West Queensland.

Jan 1, 2003

Access roads for haulage, construction or maintenance purposes are discussed with particular attention being given to the un- sealed "all weather" form of construction for Off-Highway applications. The service conditions experienced by the surfaces used in these roads is examined. These conditions are discussed in terms of the conventional engineering properties used for natural gravel material selection. Experience gained during the construction of a pipeline access track is used to illustratE material selection guidelines based on geological input and an understanding of good construction practices. TMITDnIll IrTT Ohl In many Australian situations off-highway haulage by wheel or track supported vehicles is carried on unsealed, gravel roads. Although the unsealed gravel road is the back-bone of the rural road network in Australia, in general, traffic loadings are relatively low compared to the off-highway unsealed haulage road. The cost of the haulage/access road construction component is one important factor in project planning which needs careful consideration. It is no longer acceptable that the initial rough exploration track be gradually upgraded so that it will eventually carry construction and maintenance traffic safely and efficiently. Fatal accidents and

Jan 1, 1982

By G MORRIS

The mining industry has been rightly proud of its environmental achievements and it would be fair to say that in some areas the Australian mining industry is at the forefront of world practice in environmental management and mine rehabilitation. The `environment' has certainly been a growth area over the past three decades with growing awareness in the 1960s, some large battles and the of significant legislation in the 1970s. The most important period however has been the 1980s and so far the 1990s where, in addition to the of some more rigorous legislation, we have seen the practical application of environmental management/rehabilitation Techniques.

Jan 1, 1992

By Moxon NT

The detonation pressure of ANFO can be significantly reduced by the addition of low density materials such as polystyrene, bagasse, sawdust or perlite. Laboratory and field test results have shown that homogene- ous mixtures of these low density explosives can be produced in a bowl truck and loaded into a blast hole without segregation. The detonation pressure of the mixture can be tailored to suit the material to be blasted by varying the quantity of low density additive incorporated into the mix- ture. Results obtained in the field indicate that these low density explo- sives can lead to significant cost savings without compromising fragmentation or production.

Jan 1, 1988

The issue of flyrock is critical to the operation of all mineral extraction sites that use blasting. This paper takes a risk-based approach to identifying, analysing and managing the flyrock hazard. The basic cause of flyrock generation is a mismatch between the energy available and the work to be done. It should be noted that the energy available depends on the charge confinement. This mismatch can be caused by an abrupt decrease in rock resistance (geological weaknesses), overcharging, inadequate delays between holes and rows, inappropriate blast design and inaccurate drilling. The mismatch can come about from two sides; either too much energy (charge) for a fixed burden (work to be done), or insufficient burden (work to be done) for a fixed charge. The main mechanisms of flyrock generation are rifling, cratering, face bursting and secondary blasting. Each source mechanism has different characteristics in terms of vulnerable locations and each requires different control measures. However, all controls require a high level of quality control and assurance. A range of different approaches for managing flyrock risk and determining blast clearance zone dimensions are presented. A prescriptive consequence-based approach is discussed. A conventional risk matrix based approach is outlined with some innovation regarding controls rating and uncertainty ratings. A published semi-empirical approach is discussed. Two examples of quantitative flyrock risk analysis are presented; one involves bench blasting based on a published paper and the second is a cratering example developed by the author based on consulting projects. Finally, a stochastic approach based on published work is presented which simulates cratering superimposed on face bursting mechanisms. Also, a stochastic analysis undertaken by the author of the cratering example is presented. Effective blast emission management is required for two reasons; firstly to reduce and/or eliminate safety risks and secondly to manage public perception of blasting risks such as flyrock. The conclusion of the current research is that the wild flyrock risk can be estimated using existing techniques. Furthermore, both qualitative and quantitative risk management methods as discussed in this paper can be used for flyrock management for a given blasting situation. A combination of both is considered to be best practice.

Jan 1, 2007

By Grimstone LR, Leach JHJ

An analytical technique is described to identify areas of structural disturbance to coal and interseam strata in coal measures. It is based on exploration borehole data which records seam intersections and interseam lithologies. Computerised data bases have been developed to allow processing of large quantities of borehole records. The case study discussed is located in a tectonic setting dominated by thrust faulting. It provides a mechanism for the identification of low angle and bedding plane faults. In addition it allows the preparation of plans showing the areal distribution of the thrust sheets in the statigraphic section throughout the mine prospect. The technique requires the identification of normal undisturbed depositional thickness of coal seams and interseams to be determined. This is done for coal by the identification of coal ply distribution over the area. For interseam lithologies it is based on sedimentological modelling of lithology distributions, related back to the original depositional environments. Variations from the expected values are interpreted as structural Deformations.

Jan 1, 1986

By F A. Roddick, C Swaminathan

As remaining gold deposits tend to become more refractory, some form of oxidative pre-treatment involving hydro or pyrometallurgy is necessary to maintain high metal recoveries. These pre-treatments include pressure oxidation, bio-leaching or roasting. In the past, the primary criterion for selection of oxidative pre-treatment relied mainly on the extent of gold recovery and relative economics. In this study, a different approach has been adopted, ie the quantitative determination of environmental performance of the oxidative pre-treatment processes bio-leaching, roasting and pressure oxidation to assess which had the least impact on the environment. By establishing the environmental performance of processes, waste minimisation can be addressed early in process selection. Using mass balances, the environmental theme method was applied to determine the performance, on the basis of gold treated, of the oxidative pre-treatment processes of selected plants. No clear trend was observed in the overall impacts of each of seven plants, with all but one of the environmental evaluation indices being of the same order of magnitude; this was probably due to masking effects arising from the large variations in feed composition, tonnage, and gold levels. Within each type of pre-oxidation plant however, certain trends were detectable. For instance, irrespective of plant size, ore composition or mineralogy, for the bio-leaching and pressure oxidation units, the general order of environmental impact from greatest to least was sequentially toxicity, acidification potential, depletion of resources, solid waste generation and greenhouse enhancement. For the roasters the acidification potential was the most significant. Determination of the environmental performance of the oxidative pre-treatment of a hypothetical ore in a plant of fixed tonnage was undertaken to remove the possible masking effects of variables associated with feeds of different mineralogy, gold tenor and tonnage. The bio-leaching process gave a marginally better performance than pressure oxidation, the roasting process the worst, although there was not a great difference between them. The decreasing order of contribution to the environmental index was acidification potential, toxicity, resource depletion, solid waste generation and greenhouse enhancement for bio-leaching and pressure oxidation; whereas it was acidification potential, solid waste generation, toxicity, resource depletion and greenhouse enhancement for roasting. Since the major contributor to the environmental index was the acidification potential, the environmental performance of treatment processes for the acidic effluents was calculated. After neutralisation of the net acid resulting from bio-oxidation and pressure oxidation, and the application of various scrubbing and product formation processes for the sulphur dioxide from the roasting process, it was shown that pressure oxidation gave a marginally better performance than bio-leaching, ahead of roasting. This study demonstrated the potential for the development of a predictive tool which could be used in determining the environmental performance, and thus the selection, optimisation, and improvement of pre-oxidation processes for least impact on the environment. These would allow operation of these processes within defined environmental performance limits and decisions regarding the desirability of processing various parts of a heterogeneous orebody to be made on environmental grounds.

Jan 1, 2000

The Musselwhite mine, located in northwestern Ontario, Canada, has been an underground narrow-vein gold producer since the spring of 1997. As an exploration project at the feasibility stage, much effort was undertaken to generate a geostatistical resource model that would integrate the orebodyÆs geological features, as well as the controls on mineralisation. Today as an operating mine producing over 200 000 ounces of gold per year, reconciliation studies of the tonnes and grades treated at the mill, with the feasibility model, for longer time periods, and with the grade control models, for shorter time periods, show results that are in good agreement. It was clearly demonstrated with the reconciliation to production, that the key to good reconciliation remains in the proper selection and application of the geological resource estimation method. The application of a grade interpolation technique capable of capturing threedimensionally pertinent geological features, as well as accounting for spatial grade continuity, proved to be successful in the predictability of tonnage and grade at the Musselwhite mine. Along with good mine practices, this approach, which was carried through to the operation, has produced excellent reconciliation results. The ongoing reconciliation studies at Musselwhite allow for a constant revision of the grade estimation strategy. In return, this optimisation process adds value by raising the accuracy level of production expectations. As this is an evolving practice at the mine site, further implementation developments are recommended to integrate these reconciliation procedures on a more regular basis.

Jan 1, 2002

Boliden's Aitik open pit mine located in northern Sweden, will expand yearly production from 18 to 36 Mt of copper ore during 2010. The expansion includes a new concentrator located 3 km off the pit, two new apron feeder crushers connected to the ore storages and concentrator with conveyors at a total length of 7 km. The concentrator has two lines with autogenous grinding mills and flotation each with a capacity of 18 Mt. Consequently the mine operation has to be expanded. To achieve this, there was several parallel processes ongoing; investments in new equipment, reorganisations, improvement projects in maintenance and productivity. The Aitik 72 project was started to coordinate productivity and mine planning activities. Initially the long-term strategic mine plan called for a total movement of ore and waste to increase from 40 to 72 Mt but has today increased to 89 Mt. Productivity projects have been focused on load and haul activities such as fuel economics (Renstr÷m, 2007), effective utilisation of trucks partly by increasing manning levels, improved dispatch and shovel utilisation focusing on optimal use of loader/truck fleets. The eco-driving projects previously reported have reduced fuel consumption significantly. This project is also a productivity project, as part of the fuel savings comes from minimising idle engine hours due to queues, break-downs, operator shift changes, etc but also from under and overloading. Effective use of truck fleets, ie transport of material, loading and dumping, thus excluding non-productive engine hours has been an essential motivator when deciding the size and number of new trucks required. This has resulted in a reduction of the investment with at least one but maybe two trucks. A third major project was to optimise shovels together with truck fleet by improving short-term, up to two weeks, detailed planning of drilling and shovel activities. Daily scheduled breaks for maintenance as well as planning of shovel utilisation, down to shift level are included in the production plans. KPIs and online production reports, based on real-time monitoring of drill rigs, shovels and trucks, have been an essential tool used regularly to engage and motivate mine production personal and information reporting to management. Several projects have already reached their goals. The projects will continue throughout 2010 to ensure that productivity targets are met.

May 1, 2010

This paper discusses the requirements for a successful simulation modelling study, and the steps involved in the modelling process. Advantages and disadvantages of simulation are described, and a case study highlights how not to go about it. Two other case studies, for a decline truck haulage and a block caving production operation, are used to illustrate the types of variables whose impact may be investigated. Typical results are presented to indicate the sorts of presentation styles the author has found useful for conveying study results to project sponsors. Standard spreadsheet charting techniques can be very useful in this respect, but the possibilities are limited only by the imagination of the study team.

Jan 1, 2000

By Torrance AC

A joint research programme conducted by BHP Central Research Laboratories and Du Pont Wesfarmers Pty Ltd examined the effect of the size of cast primers on the run up and steady state detonation veloci- ties of ammonium nitrate based explosives as a function of blasthole diameter. Both continuous and point to point velocity of detonation meas- urement techniques were used. The field trials examined a number of the Du Pont HDP series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the run up velocity of 187mm diameter ANFO charges is negligible using cast primers as small as 150g. owever, emulsion and watergel explosives did exhibit run up in both 187 and 311mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blasthole diameters.

Jan 1, 1988