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A key issue in maintaining the mining industryÆs social contract to access community-owned resources, is the need to be able to demonstrate professional management of resource extraction and the risk associated with mining hazards. Significant failures such as disease relating to coal dust and asbestos and mine disasters such as Moura, Appin and Gretley have resulted in judicial and legislative interventions that respond to the community outcry but do not necessarily effectively manage the longer term risk in a sector driven by new technology. With the implementation of recent amendments to the Queensland Professional Engineers Act, senior engineers in all industries including the mining industry are required to be registered and to demonstrate that they have æmaintained competency in the practice of engineering in the area of engineering for which the (engineer) is ... registeredÆ. This may be facilitated through a report produced by an æAssessing EntityÆ. These entities are approved by the Minister on advice from the Board of Professional Engineers, Queensland. Engineers Australia and The Australasian Institute of Mining and Metallurgy (The AusIMM) are the two professional bodies approved as æassessing entitiesÆ charged with facilitating successful implementation of the process established by the legislation. The scope of the legislation covers engineering enterprises in Queensland and engineering activities elsewhere that may have been designed in Queensland. There is currently a challenge to determine what the necessary health and safety competencies for the mining industry are and how the maintenance of these competencies will be assessed. The different approaches taken by the two assessing entities are compared and contrasted. At the legislative level, establishing an obligation to assess professional competency is simple, but at the level of the profession, it is new ground that warrants a substantial research and development input. The challenge is to develop criteria by which the quality of such system can be assessed. The comparison is made by considering such issues as equity, effectiveness, efficiency, objectiveness and transparency. These five indicators are considered in terms of how they are applied in other sectors and how they might be applied in the mining sector.

Jan 1, 2009

Many sampling standards arrive at a value for the prescribed sample mass by assuming a specific relation between the sample mass and the relative standard deviation of the fundamental error and assigning a value to the tolerated coefficient of variation. In order to obtain an equation that provides a relation between the minimum sample mass and the particle properties, many different models for the drawing of a sample have been developed. Here, a model for the drawing of a sample is proposed which can be considered to be a generalisation of the model used in GyÆs sampling theory. Using simulations, it is illustrated that the generalised model can lead to a better correspondence with actual sampling processes.

Jan 1, 2005

By A Clark

When production targets are not being reached it is essential to determine what the operating problems are so that remedial action can be taken. It is also imperative that all persons who are part of the production stream within a mining operation know and understand what the operating difficulties and delays are so that corrective action is effective. This includes the supervisors, superintendents, planning team members and managers. A new approach recently adopted at Hilton Mine to help identify these operating difficulties has been to use short-term schedules and reports known as the Daily Shift Schedule Controls (DSSC), and the Daily Weekly Operating Reports (DWOR) respectively. These control elements have enabled management and supervisory staff to accurately identify labour inefficiencies and ultimately determine capital resources.

Jan 1, 1998

THE de-silverizing of base bullion at the Port Pirie works is carried out in accordance with the principles of the well-known Parkes process. The base bullion produced by the blast furnace department carries (apart from silver values) impurities, the chief of which are copper, antimony, and arsenic. In order to more clearly indicate the grade of the base bullion, the following analysis, representative of a half-year's production of base bullion, is submitted...Before proceeding with the actual operation of de-silverizing, it is necessary that the impurities, copper, antimony, and arsenic, should be eliminated. This is accomplished in the following steps :- (1) Removal of Coppel - Copper is largely present in the base bullion as dissolved sulphide, and this is removed by liquation in a reverberatory type furnace, of which the following are the essential details :-Working temperature 7500 to 8500 C.Coal consumption per 24 hours 2 tons.The hearth of the furnace is encased in a steel tank 22 ft. 4 in. long by 13 ft. 4 in. wide by 2 ft. 10 in. deep; the bottom of the tank is covered by a depth of composition conforming to the invert :-Cement 39 cwt.Brick dust 8.4 tons.Fireclay 0.6 tons.Sand 0.6 tons...

Jan 1, 1922

By R L. Brathwaite

In New Zealand, volcanogenic massive sulfide (VMS) deposits are found in three main geological environments associated with: 1.   ophiolitic basalts of Oligocene age in Northland and East Cape (eg Pupuke, Pakotai, Parakao and Lottin Point); 2.   with chert and pillow lava in greywacke sequences of Permian-Jurassic age (Torlesse and Waipapa terranes; eg Kawau Island, Te Kumi and Maharahara) and their metamorphic equivalents (Haast Schist; eg Moke Creek and Waitahuna); and 3.   with greenschists (metabasalts) and metaserpentinite of Permian-Triassic age (Ponamu Ultramafics) in Westland (eg Bowen and Wilberg ranges). The deposits consist of small lenses of disseminated to massive sulfide minerals, mainly pyrite and chalcopyrite. Small quantities of copper ore were mined from some deposits in the 1800s (eg Kawau Island from 1846), with the last mining at Parakao from 1961 to 1966. Several deposits have been recently examined for their gold potential with assays on sulfide rock samples as high as 75 g/t Au (Lottin Point).

Jan 1, 2005

We are moving into an era where we experience the consequences of the skills crisis û namely many resource models have been generated by inexperienced people under pressure to deliver high quality resource estimates in unsupported environments, often without technical mentors. These resource models form the basis of our decision to pursue actual mining. This begs the question: how valid are the resource models that form the basis of our mining decisions? This paper presents various model validation tools such as comparison of input and output statistics, swath plots, sectional or bench comparisons between drill holes and models as well as a variety of other approaches. Each model validation tool currently used in industry is examined:how the tool generates results,what assumptions exist,what constitutes a pass/fail in the test, and what interpretations to consider when using the validation tool. Each validation toolÆs suitability and the inherent flaws in the underlying assumptions are also discussed. These are supported with examples of good versus bad validations. Our principles based reporting codes provide flexibility in how models are generated and what approaches and/or parameters are used to generate resource estimates. This flexibility works well when used by experienced practitioners. However, our reporting codes assume a level of experience not always available in the current skills crisis. This paper seeks to provide minimum model validation prerequisites for model acceptance and suitability, regardless of the resource analystÆs experience. As we move forward, our immediate challenge is to ensure our baseline resource models are material, transparent and competent.

Jan 1, 2009

The Court rejected the suggestion that CRAE had actively misled DMR concerning the worth of its tenements. The Court agreed that CRAE remained silent about certain significant information concerning CRAE's own tenement area. It was a significant question as to what duties CRAE'was under, given that it was in joint venture with DMR in respect of one of the tenement areas. Did that joint venture create an obligation on CRAE to disclose everything it knew? The Court said no. The Court said that the fiduciary duties were defined by the terms of the farm-in agreement between DMR and CRAE. When the Court examined the disclosure obligations within the confines of the contract, it held that CRAE had not breached those terms.

Jan 1, 1990

By Low Russell

Mark Westfield, writing in The Australian on 16 May 1994 stated: The role of the independent expert is crucial to Australia's investment system. When it falls down, there can be very dramatic consequences. The scope of these consequences was dramatically illustrated in the decision of Rogers J. at first instance in Cambridge Credit Corporation v. Hutcheson (1983) 8 ACLR 123 when the auditors of the failed company were found liable for breach of contract and faced a damages award of $145 million, well in excess of their insurance cover. No comfort should be sought in the fact that this decision was overturned on appeal, for the result of the appeal rested on whether there had been a causal connection between the breach of contract which had occurred and the loss suffered, rather than on the fundamental principle of auditors' liability. Thus: Those who prepare experts' reports in company cases carry a heavy moral responsibility, whatever their legal duties may be... Unless high standards are observed by those who prepare these reports, there is a danger that systems established for the protection of the investing public will, in fact, operate to their detriment through reliance placed on those reports and on the reputations of those who furnish them. In lending his name, the expert will often, as in this case, be lending a name to conjure With.

Jan 1, 1995

The modern resource extraction enterprise is a complex capital intensive business operating in a world of constantly evolving social, environmental and economic scrutiny. Investors, government, media and special interest groups expect to see business environmental and social performance respond and deliver increasing corporate responsibility and sustainability.   Thorough interrogation of business performance using a multi-disciplinary due diligence approach presents a more sophisticated review and benefits beyond the traditional compliance/conformance 'audit' style assessment.   Using a due diligence approach allows assessment through a comprehensive lens which examines potential short- and long-term risks including sometimes less tangible environmental and social liabilities, and informs management, investors and regulators of broader business performance. This approach provides information in a form that business can measure performance in a repeatable and enterprise wide sense.   This paper provides an outline of the due diligence process applied in this way, drawing from lessons learnt and industry based experiences in the due diligence process and the benefits and tools that can  be applied in an environmental and social due diligence business performance assessment

Jun 1, 2010

The minerals industry focus over much of the past twenty years has been on cost reduction and production growth supported, but not driven, by technology improvements. Mergers and acquisitions, and the demands of financial markets, have been high priority items whereas research and development and technology based innovation have received less attention and have been cut back in many companies. Technology improvements will be critical if the industry is to make progress on the stated aims of improving energy efficiency, reducing water usage and maximising recovery from deposits. They will also be important for improving capital efficiency and in treating difficult deposits. However the role technology based innovation will play both in the overall industry, and within individual companies, during the next decade is quite uncertain. There are major challenges in progressing technology based innovation in an industry with limited technical resources which is dominated by long life high capital operations. Specific opportunities for energy and productivity improvements exist but face significant technical and structural barriers that need to be overcome if the industry is to significantly improve performance. Current evidence suggests that changes in approach will be needed for these improvements to be realised. Recent studies in the United States and Canada have highlighted the wide range of energy performance across the industry and the scope for marked improvement from both incremental improvements and increased research and development. Comminution, material transportation and underground mine ventilation were identified as high priority areas. Opportunities within these areas are discussed both in respect of specific technologies and in how they may change performance. The role of open innovation as a source of new technology is also discussed. This is an abstract only. No full paper was prepared for this presentation.

Sep 13, 2010

Australis Mining N.L. operates a continuous mode carbon-in-pulp (CIP) gold plant, processing sand and slime tailings from previous gold mining operations in the Norseman area. Plant design is that of conventional countercurrent contact between pregnant pulp and activated carbon. Gold desorption is achieved by the Zadra process using near boiling tempera- tures and atmospheric pressure. Process water is drawn from nearby Lake Cowan (saline). The plant operates at, or above, design specification of 400 dry tonnes per day. This paper describes the plant design and operating processes utilised in optimising throughput and gold recovery. TNTDnPTTnmTnM Favourable world gold prices and substantial reserves of sand and slime tailings prompted Australis Mining N.L. to construct a gold extraction plant during 1981. The projected plant throughput was set so as to complete treatment of available tailings over a three year period. Metal- lurgical tests indicated that, with a regrind facility satisfactory gold recovery could be achieved using a countercurrent CIP process. Reflecting the entry of Australis Mining N.L. into its first large scale treatment operation, the plant design emphasised simplicity but effectiveness of Operation.

Jan 1, 1982

Most people are familiar with Euclidean dimensions: zero for a point; one for a line; two for a plane; and three for a volume. Howeverbobjects are not actually Euclidean, but lie somewhere between Euclidean æend-membersÆ with a non-integer fractal (or æfractionalÆ) dimension. The fractal dimension D is a measure of the relative importance of large versus small. Consider the trace of a coastline on a map. It has a fractal dimension (1 =D =2) somewhere between a line (dimension = 1) and a plane (dimension = 2). The more tortuous the coastline, the higher the fractal dimension, and the closer it becomes towards a plane. The concepts of fractals and spatial geometry can be applied to a wide range of geologicaVmining problems as well as than those dealing with space. One commonly quoted fractal relation is the log-log relationship of ore-grade and tonnage. Until recently, we have never been able to define or measure spatial-geometry, but new developments in mathematics have provided a means by which to quantity and apply it to our problems.

Jan 1, 1992

By R J. Goldfarb, A B. Christie, D I. Groves

Small orogenic gold deposits have the same deposit-scale geological and geochemical features as those that characterise giant orogenic gold systems (>16 Moz Au). Therefore, a broader-scale approach is needed to identify the critical controls on giant deposits and their disproportionate distribution throughout time and space. Ages of giant gold systems cluster around well-defined periods of lithospheric growth at continental margins, and it is orogen-scale processes during these Late Archaean, Early Proterozoic and Phanerozoic times that determine gold endowment of a province.   A critical factor for giant orogenic gold provinces appears to be asthenospheric upwelling at the time of gold mineralisation to most effectively transfer the thermal energy required to initiate and sustain high hydrothermal fluid flux. The extent of this fluid flux should be related to thickness of the lithosphere beneath a province at the time of gold mineralisation, such that giant gold deposits are much more likely to develop in orogens with oceanic or thinned continental lithosphere. A proxy for the latter is likely to be a short premineralisation crustal history such that thick subcontinental lithospheric mantle was not developed. Conversely, orogens with protracted premineralisation crustal histories are more likely to have a thick subcontinental lithospheric mantle, which is difficult to delaminate and, hence, such provinces will normally be poorly endowed. The nature of the lithosphere also influences the intrinsic gold concentrations of potential source rocks, with back-arc basalts, transitional basalts and basanites enriched in gold relative to other rock sequences. Thus, segments of orogens with thin lithosphere may be defined by conjunction of giant-scale fluid flux through gold-enriched sequences.   Although the nature of the lithosphere plays the crucial role in dictating which orogenic gold provinces will contain one or more giant deposits, the precise siting of those giants depends on the critical conjunction of a number of province-scale factors that control fluid conduits, traps, and seals in tectonically and lithospherically suitable terranes within accretionary orogens.

Jan 1, 2005

This paper describes a mine truck hauling process called "Truck Jigging" which is currently the subject of a process patent application.The investigation explores the production and cost advantages of using the potential energy available in a descending haul truck to assist in elevating an ascending vehicle. Applications are studied for both strip cut mines and open pit operations. Various mechanical connections between the two vehicles are considered, based on a pulley mounted rope system. Fifteen year operating cost estimates show savings of up to 26.5 percent over conventional mine truck operations.

Jan 1, 1989

By A J. Broome

Since 2003, there has been an unprecedented growth in the demand for engineering, technical and project services in the mineral industries. This demand for services became evident in Australia earlier than many other markets and has since spread globally. This growth has created significant issues for the strategic direction and planning by the service provider. Such strategic questions include:- how fast to grow, how to recruit, train and integrate new staff, what market sectors to service, the selection of targeted customer sectors and managing strategic growth with short term demands and commercial reality. These factors are discussed using in depth experiences and examples that illustrate these strategic approaches. The relevance of this new industry environment to New Zealand services will be highly discussed.

Jan 1, 2007

One of the major changes in the resource industry in the nineties has been the re- internationalisation of the industry. The history of the resource business has been one of companies from the developed world utilising the cash flows from their operations to explore and develop mines in less developed regions of the world. This resource development has progressively generated wealth and economic development, which in tum, has led to a new generation of exploration and mining projects.   InSouth America, Chile had led the way in a mining resurgence, now closely followed by Argentina, Brazil, Venezuela and Peru. Although Chile has long had a significant copper mining industry, the pre-nationalisation phase was driven by American capital; the current phase has been spearheaded by RTZ - BHP at Escondida with Canadian junior companies, in particular, providing major speculative impetus. The Australian junior companies have not been significant in South America.   Although Canadian and USA exploration appears to be in decline, the mining industry, particularly in gold, is buoyant in North America. Interestingly, a number of listed and unlisted Australian companies are active, particularly in United States exploration.   Australian-based companies have dominated the South-East Asian exploration scene, especially in the Vietnam region. To date, the combination of political and legislative uncertainties have failed to lead to significant resource developments in this region. The area remains one of great potential, as exemplified by the exciting developments in Indonesia.   The Philippines has a history of mining, and this has been dominated by both local and North American operators. Both large and small Australian resource companies have a presence in the Philippines, and the development of the copper-gold potential could be impressive over the next decade.   The tales of the undeveloped mineral potential of China are probably rivalled only by the supposed strings of virgin Russian orebodies! Many Australian companies appear to have looked but few have chosen to proceed with Chinese developments. There seems little likelihood that China will, in the foreseeable future, rival South America as a target for Australian and North American resource capital.   Papua New Guinea has had an active, albeit chequered history in mining, with Australia long being the predominant source of exploration and development funds. The developing nation status of PNG has generated extreme uncertainty, with the current exploration scene all but dead. Most recently, the international flotation of Lihir Gold has tested the international and Australian investment community's commitment to PNG resource development.   The Australian exploration scene continues buoyant, although dominated by gold. The base metals scene is generating, on average, one significant base metal mine developed every couple of years. This is probably the fastest rate of significant base metal development in Australia's history.   The gold scene has been one of incredible dynamics, and there is no evidence that this momentum is waning. The development of new exploration techniques, together with a number of the companies reaching a critical size, has added to the momentum in the industry.

Jan 1, 1995

By D S. Collins, Z Hosseini, I Pinnock, Y Toya

Microseismic monitoring is regularly used in the mining and geotechnical industries to provide detailed information about rock mass response to operational activities. This paper implements a variable 3D velocity model (VM) at a North American hard rock mine with the aim of further improving the accuracy of seismic event locations. A collapsing method is also used to help analyse two individual seismic event clusters at another North American hard rock mine. In the first case study, the location accuracy of events is shown to improve by moving from a conventional single VM to a variable 3D VM that accounts for voids and different geological domains. The modal average for the event location accuracy improved from 14 m to 5 m when the 3D VM was used. Additionally, the single VM failed to locate 26 per cent of the seismic events that were located by the 3D VM. In the second case study, the distribution of seismic events was further enhanced by using a collapsing method that highlighted planar structures. The collapsing method was performed on two large event sequences that occurred in close proximity and identified different seismic event distributions. One aftershock sequence aligned along a plane, suggesting an activated structure, while the other large event sequence had a more 3D distribution of events, suggesting a complex stress redistribution on smaller structures.CITATION:Pinnock, I, Collins, D S, Toya, Y and Hosseini, Z, 2016. Large event sequence analysis and 3D velocity models for seismic event location accuracy, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 879–884 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Technology is playing an increasingly large role in the operations of our mines. There is a temptation to regard the implementation of technological systems as the objective itself when, in reality, systems are used to support a business process. Only when the process succeeds will the systems be seen to succeed. Understanding the distinction between system and process is critical. This understanding, together with the resultant holistic approach, is considered to be critical to successful implementation and operation of Mine Control process. This paper examines the critical factors essential to success in establishing and sustaining a Mine Control process that maximises benefits to an operation. These factors have been developed during the author's experience of nearly 30 years in Mine Control projects across over 50 sites. Each factor is discussed in relation to real world examples at well-known mines.

May 1, 2010

By D J. Brake

There are many sources of gas in underground mines including development and production blasting, strata gases, spontaneous combustion, diesel equipment, chemicals used for a wide range of functions, welding activities and fires.It is only in relatively recent times that electronic gas monitors (or detectors) have become both safe and affordable for routine use.In modern mines, gas monitors should be in daily use by the ventilation department as well as blasting re-entry (or clearance) crews, and are often used by drilling crews, shift supervisors, hygienists and mine rescue or fire fighting crews.When first released, electronic gas monitors needed to be sent off-site periodically for calibration at a suitable accredited laboratory. Between calibrations, their accuracy was unknown. More recently, ‘bump testing’ and field calibration has become possible on the mine site, improving both reliability and safety as well as reducing the total number of gas monitors that need to be in use.There has been almost an overwhelming increase in the number and sophistication of gas monitor features in recent years. This paper reports on a case study into the key criteria that ventilation practitioners should be aware of with respect to the specification and selection of the most recent gas monitoring systems, and recommends good practice for site-based operation and calibration.CITATION:Brake, D J, 2015. Specification and selection of hand-held gas monitors (detectors) for underground mines, in Proceedings The Australian Mine Ventilation Conference, pp 143–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

Flotation testing has been done at laboratory scale on hematite mineral and ore samples using stage additions of various hydroxamates. Chemisorption of hydroxamate species onto the hematite surface was inferred from the results, possibly involving both the undissociated hydroxamic acid and hydroxamate ion as maximum recovery occurred close to the pKa of the hydroxamic acid. Flotation testing on a specular hematite ore containing 40 per cent Fe and 42.5 per cent silica gave highest iron grades in concentrate at pH 6, in contrast to published data which suggested pH 9 as the optimum value for ore processing. Using octyl hydroxamate, a rougher concentrate assaying 67 per cent Fe at 51 per cent recovery was obtained using four stage additions of 50 g/t at pH 6. For lower grade concentrates still meeting the chemical analysis for pigment grade micaceous hematite (minimum Fe assay 60 per cent) iron recoveries of 80 per cent were possible for stage additions of 50 g/t octyl hydroxamate in the pH range 6-8.

Jan 1, 1999