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The emerging discipline of ægeometallurgyÆ is not new but is becoming increasingly recognised as a discrete and high-value activity that reflects an ongoing commercial and cultural trend towards more effective mine site integration and optimisation. The AMIRA International P843 æGeMIIIÆ project (Geometallurgical Mapping and Mine Modelling) is a major new cross discipline research collaboration designed to provide support for this emerging industry trend. The project is currently supported by 18 global mineral companies and involves collaboration between the CODES Centre of Excellence (University of Tasmania), JKMRC and BRC (University of Queensland) and CSIRO Exploration and Mining. These groups represent recognised research excellence in the fields of economic geology, automated core logging, advanced microscopy and process mineralogy, mineral processing, mine planning and resource optimisation. The needs and challenges of geometallurgy as an integrated activity will be outlined together with the ongoing contribution and aims of the AMIRA P843 æGeMIIIÆ project. The main emphasis is on development of predictive geometallurgical indices for key processing performance parameters that reflect inherent geological variability. The ultimate aim is to provide predictive indices of geometallurgical performance that can be confidently embedded into resource models and used for risk-defined mine planning and optimisation.

Jan 1, 2008

Projects to be undertaken in remote locations require special attention with regard to constructability from the very first stages of design. This is to ensure not only that the project is compatible with the environment in which it' is proposed to be built, but that it does not require facilities or special construction equipment and expertise that is not available in the proposed location. This paper draws on experiences gained on projects in Alaska, Northern Canada, South East Asia, outback Australia, and more recently Bougainville, in Papua New Guinea, where over the past 5 years Minenco has undertaken in excess of A$120 million of work on a number of different projects for Bougainville Copper Limited Although many of these projects have been close to large populous cities, which have been served by regular shipping and airline services, the locations have not had the availability of construction facilities which exist in major cities of Australia and thus can only be considered as remote locations by current day standards. As a result, every nut bolt and washer has had to be brought to the job site by the construction company. No hardware or electrical warehouses existed for those forgotten half dozen high tensile bolts, spring

Jan 1, 1986

Anglo Platinum recognised with its expanded operations the need to change its evaluation strategy due to increased sample volumes and the pressure it created at laboratories. The sender/receiver analytical scenarios had to change in order to curb costs and to prevent substantial investments in new sampling and analytical facilities. Given the high cost associated with correct sampling systems and sampling protocols and the shortage of technical resources a strategy of single point sampling and analysis was introduced. The analysis was then done at an ISO17025 accredited laboratory with ten per cent checks, subjected to careful statistical scrutiny. Logistical problems increased with respect to weighbridge congestion, maintaining sampling quality, throughput of samples in the sample preparation areas, manual quality control systems in place, audit trails and analytical capacity throughout all operations. This required the expedited improvement of existing sampling practices and the development of new sampling methods and equipment. Anglo Platinum is classifying and standardising sampling equipment, sample preparation and analytical procedures for all process streams with the view to minimise overall uncertainties. Major investments were made into a customised LIMS and automated equipment for data management, reduction of manual transcription errors and streamlining of sample processing. Anglo Platinum is committed in rolling out the enhancements to all sites as priority dictates.

Jan 1, 2008

Passive systems for the treatment of acid mine drainage (AMD) are typically more economic in the long term than active systems. Various flow charts for treatment selection have been prepared by scientists in the USA, however, they have typically not included a variable important at New Zealand AMD sites on the West Coast: topography and available land area. Very steep topography, dense and often protected vegetation (and animals such as snails), and a high-rainfall climate result in AMD with very high flow rates in locations with very limited space for remediation. Flow charts specific to New Zealand have been prepared which accommodate topography and available land area. Parameters necessary to use the flow charts are iron and aluminium concentrations, pH, ferrous to ferric iron ratio, dissolved oxygen concentration, topography and available land area. Prior to full scale construction, is it recommended that flow rates be quantified, small-scale trials be conducted, and cost, effectiveness, limitations, and risk of failure be reviewed for various options. One full-scale remediation system has been installed in New Zealand based on this methodology and another is planned. The performance of these systems, as well as future systems to be installed, will be used to validate these treatment system flow charts.

Jan 1, 2007

By Roberts JD

The design and installation of a major on-line stores and purchasing system, with built-in maintenance reporting and plant register capabilities, needs more than just close attention to computer design details. When the system must be available almost 24 hours a day to a number of mine stores sites, and is used by a variety of mining staff including engineers and stores clerks, as well as by remote purchasing and office staff, then simplicity of use, availability, fast response times, and other human factors become vital. Critical aspects include easy to use screen design, involving a change from the traditional hierarchical menu system, and fallback and recovery to the last transaction. Business, people and systems objectives need to be established at the preliminary design stage, so that results can be measured and corrective action taken. The amount and type of user involvement and training, at all stages from initial design to systems tuning, has a major effect on people wanting to use the system. Active user participation in systems design, data definition and collection, and use of relevant training material is needed. Project management and design problems can arise in working with database oriented computer staff, and certain design features are found useful in ensuring a responsive, robust overall system.

Jan 1, 1983

Development of the Greenvale orebody, containing 40,000,000 tonnes of nickel ore, began in 1971 and production commenced in 1974. Annual capacity is 2,800,000 wet tonnes. The variations in ore grade and physical characteristics which occur throughout the ore- body had a major influence on the selection of mining methods, grade control procedures, and equipment. After removal of overburden by scrapers, ore is excavated by draglines sidecasting into windrows. Feed to the crushing plant is .reclaimed by front end loaders into rear dump trucks according to a grade selection pro- gramme. After crushing, ore is stockpiled into blended units of ore of required quality. Ore is stacked and reclaimed for train loading using techniques designed to give maximum mixing of ore characteristics through Bach unit. These procedures are repeated on discharge at the plant site at Yabulu. The railway, constructed by Queensland Nickel Pty. Ltd. to Q.G.R. standard, and operated by the Q.G.R., is 216 km long and includes eight major bridges and three tunnels. Two trains per day, one of four locomotives and 92 waggons, and one of three locomotives and 69 waggons, haul crushed ore to Yabulu. Train loading is semi-automatic. A small township and associated services have been constructed for employees at Green- Vale.

Jan 1, 1974

By R Grogan

The Ungay-Malabago polymetallic deposit, currently owned by Lafayette Mining, is located on the eastern end of the island of Rapu-Rapu which lies east of the city of Legazpi in the Philippines. The island is sparsely populated and has largely been deforested by extensive logging some 30-40 years ago.The deposit is situated on a plateau some 200 m asl and lies about one kilometre inland from the coast. The site topography is difficult with minimal flat areas for plant facilities. The region around Legazpi is subject to volcanic activity and though the island is not affected it is in a seismic zone. There is no other mining or other industrial activity on the island, the local inhabitants being engaged in subsistence farming and fishing. These activities place a high level of responsibility on the mine operator with regard to the environment and the provision of employment and training to the local inhabitants. Although no previous mining was carried out at Ungay, shallow pit mining for high-grade direct smeltable copper ore has occurred during the mid-1900s in an area, known as Hixbar, some 2 km west of the deposit This area is currently being explored by Lafayette.

Jan 1, 2002

This paper describes a steam outburst in a metal mine which occurred in December 1992 in Japan, resulting in two fatalities. The outburst occurred just after blasting in a heading face 600 m below surface (SL-50 m), 1664 m from a mouth of the mine. The scale of the outburst was large and the fragments of the outburst spread up to 34 m from the face, the total volume of the outburst was estimated to be 206 m3. The outburst materials were mostly clay originated from the typical surrounding rock of sulfide ore and basalt. The shape of the larger outburst fragments were slabs with a thickness of 10 to 20 cm. The victims were found in a main ventilation air shaft, 175 m and 380 m from the face, respectively. The mine mainly produces copper, lead and zinc. The face was ventilated by a 560 mm diameter duct with a fan and the strata temperature of the rock was estimated to be in the range of 120 to 140¦C. There is a famous hot spring near the mine. A thorough investigation into the unprecedented accident was made including an on-site inspection and investigation of rock characteristics in laboratories.

Jan 1, 2005

Vatukoula is a gold mining township situated at the south-west periphery of a Tertiary caldera which measures 3 miles by 4 miles. Erosion of the caldera resulted in the formation of a topographic depression, called the Tavua basin, covering about 30 square miles. This area, also known as the Tavua Goldfield, has been the site for spasmodic prospecting since the initial discovery of gold in 1932.The mineralization at Vatukoula is typically epithermal with the gold occurring as tellurides, auriferous sulphides, and to a much less extent as native gold. The lodes are confined to three major structures i.e. north-west shears, flatly dipping structures (flat makes), and local shatter orebodies.Within these structures, at least five types of controls are recognized to account for the localization of the oreshoots. The dominant control is structure.The lode structures are related to the overall structural pattern of the Tavua basin. This pattern, which is controlled by the collapse planes of the caldera and a north-west shear system, produced a "shatter block" atVatukoula and elsewhere around the caldera.Structural analysis indicates there are certain areas in the Tavua basin where exploration could be rewarded by the discovery of orebodies with similar controls to those of the productive Vatukoula block.

Jan 1, 1967

By P Elliott, D Pershke

In a minerals processing context, sustainability is about using natural resources more efficiently to achieve maximum economic benefits with minimal environmental impacts. It embodies five overarching themes, which the paper will illustrate with practical examples from Australian minerals processing plants. These are:resource utilisation and materials efficiency,process waste reduction and enhancement of co-product values,reduction of water use and impacts,reduction of energy requirements and greenhouse gas emissions, andenhanced control of minor elements and toxic materials. Sustainability could be embedded profitably in minerals plant design in three dimensions: 1.technology,2.design, and3.operations. This presentation discusses a set of principles that could be applied to minerals processing technologies and provides an outline of sustainability assessment and opportunities evaluation tools. The application of the tools is illustrated through a case study by analysing a suite of nickel processing technology routes. The analysis reveals that current generation of nickel processing technologies do possess real potential to emerge as sustainability champions in integrated processing of nickel ores and concentrates, if they are designed, engineered, and operated for sustainability and adapted effectively to site specific constraints and opportunities. The paper will address data gaps and uncertainties regarding the impact of scaling up of pilot-plant performance, and provides strategies to overcome them.

Jan 1, 2006

Queensland Mines Limited operates a small uranium treatment plant at Nabarlek in the Arnhem Land Aboriginal Reserve, some 265 km due east of Darwin. It was the wish of the local Aboriginal people that the ore be treated over an eight year period and that no township be constructed in Arnhem Land. Due to these wish- es it was decided to house employees and their families in Darwin and fly the employees to the minesite for work rosters. A singleman's style camp only was constructed at Nabarlek. To satisfy the Aboriginal people's wishes all recreation time is spent offsite thus lead- ing to a roster system whereby employees spend three distinct periods of 6, 6 and 4 days on- site, broken by recreation periods of 3, 4 and 5 days in Darwin, during each 28 day period. Employees are divided into four opposing rosters, which allows at any given time for approximately half the workforce to be onsite and the other half on rest and recreation leave in Darwin. This method of staffing has generally proved to be most satisfactory although at times problems arise, in terms of both product- ion and social effect not normally encountered when operating within more conventional circum- Stances.

Jan 1, 1984

This paper presents the water management plan of the Mae Moh Project in the North of Thailand, which includes a large lignite opencast mine and thermal power plants. Lignite production will increase from the present 5.5 million tons per annum to approximately 20 million tons per annum by 1995 when the pit area will be about 20 sq.km. and the depth at over 300 meters. Seven power plants are proposed of which two are under construction. The total capacity to be installed is 2,925 MW. The principles considered for water management are firstly flood protection, including drainage of the mining pit and diversion of the Mae Moh stream away from proposed future mining areas; and secondly, a plan to meet the water requirement of the thermal power plants, while maintaining downstream supplies for irrigation and other purposes. The limited annual run-off of Mae Moh and Mae Chang watershed basins are inadequate for the proposed power plants. A study has been prepared to compare two approaches, namely conveying water from remote watersheds to meet the water requirement of the power plants up to total installed capacity; or by limiting future total generation, at the existing site, to only 2025 MV.

Jan 1, 1988

Broken Hill South Limited's discovery of phosphate deposits in the northwest of Queensland in 1966 prompted intensive exploration which has proved phosphate rock in excess of 2,000 million tons at ten separate deposits.Systematic exploration for phosphate in Australia was initiated by the company in 1964. Early in 1966, an investigation of oil wells in the Georgina Basin in the Northern Territory and Queensland revealed widespread anomalous phosphate in early Middle Cambrian Beetle Creek Formation and Thorntonia Limestone. Phosphorites recognized in oil wells in the southeastern part of the Basin, Queensland, led to the discovery of the Duchess deposits. Exploration of the Beetle Creek Formation since 1966 has disclosed nine other sizeable deposits north of Duchess around the eastern margin of the Basin. The Lady Annie and the adjoining Lady Jane deposits, by reason of their location, 160 miles south of the Gulf of Carpentaria, are expected to be the first to be brought into production.Beneficiation testing and engineering investigations commenced in 1967. Transport between the deposits and various port sites in the Gulf of Carpentaria has been extensively studied and a slurry pipeline as a means of transport to a deep water island port, is now being investigated.

Jan 1, 1971

This paper examines the latest advances in mine drive and motor systems. In the last decade, the drive technology employed for large mine winders has migrated from the traditional dc technology to ac motors with cyclo convertor drives. Recent advances in pulse width modulation (PWM) drives have resulted in these being applied to large winder drives. While having many advantages for the winder system, the PWM drive must be carefully designed to ensure long-term reliable operation. When combined with induction motor technology, the PWM drive presents the ideal solution for winder drives. This paper examines the factors in choosing a suitable PWM drive for a winder installation. Factors under consideration include: winder duty cycle, drive rating restrictions, choice of power semiconductor device, cooling, and low speed operation.The cage induction motor is the motor of choice for large winder drives and has a number of advantages over the synchronous motor. The induction motor is ideally suited to integrated winder applications where the motor is built inside the friction drum, as installed at WMCÆs Olympic Dam site. The challenges of integrating the induction motor into the friction drum will be detailed, including: assembly, ventilation, air gap adjustment, and position sensors.

Jan 1, 2005

By Corbett GJ

Comparisons between individual SW Pacific Rim gold deposits have facilit-ated proposal of a new classification of porphyry-related mesothermal gold deposit types. Carbonate base-metal gold systems form at relatively high crustal levels, peripheral to porphyry intrusions. There is a spatial assoc-iation with major structures which focus fluids from degassing porphyries at depth. Milled matrix intrusive breccias and extrusive maar volcano/ diatreme breccias form as a result of pre-mineralisation phreatomagmatic eruptions. These focus degassing magmatic fluids by the provision of fracture ground preparation, typically within competent host rocks, adjacent to the breccia bodies. Local dilational structures control the form of individual deposits which may contain bonanza gold grades at sites of fluid quenching and/or repeated mineral deposition.Early quartz veining and porphyry-related alteration is common and later gold mineralisation typically occurs in association with carbonate veining and Fe and base metal sulphides as Zn > Pb > Cu. The progressive cooling by mixing of the upwelling mineralised magmatic fluid with descending bicarbonate waters, produces characteristic zonations in carbonate compositions. These vary with distance from the porphyry source, from Ca through Mg, Mn and distal Fe types. Gold mineralisation is preferentially distributed within the Mn/Mg carbon-ates.

Jan 1, 1994

By Robinson WB

An accurate and rapid assessment of coal resources, such as that provided by computer modelling, forms an intergral role in evaluating CSR's coal deposits for future development. An in-house system utilising a number of geological, engineering, costing and financial evaluation routines has been developed for DEC VAX computers. The system is currently being upgraded and enhanced to meet the demands at the various mine sites. Computer modelling of the geology is performed on encoded drillhole information and coal core chemical and physical analyses. A conceptual mine plan is formulated then digitized and superimposed on the geological model. Insitu and product coal reserves and qualities as well as overburden and parting quantities are then calculated for each strip or block. These strip parameters are then transferred to the mine scheduling routines to determine the most efficient mining sequence for the mine plan. Cost factors and scheduling data for equipment specified in the conceptual mine plan are used in the mine costing subsystem. The financial subsystem then evaluates the likely return on investment. Future enhancements to the system include improvements in the response time through the introduction of interactive graphics, the direct interfacing of geophysical and analytical data, and further development of a geotechnical'database.

Jan 1, 1983

By R Buerger, D Barrett, P Hodkiewicz

The Emily Ann nickel mine is owned and operated by LionOre Mining International Ltd. The deposit was discovered during 1997 and is blind, concealed beneath 25 m of transported cover and a further 100 m of unmineralised Archaean felsic rocks. Nickel sulfide mineralisation is hosted predominantly in strongly deformed, altered and metamorphosed Archaean komatiitic ultramafic rocks. Subordinate felsic-hosted, remobilised mineralisation is also present. Mining of ore commenced during late-2001. Since the early days of exploration drilling, through feasibility delineation drilling and subsequent mining, a geological model involving thrusting and folding of a komatiitic-hosted nickel sulfide deposit has been an evolving theme. Development of appropriate mine geology procedures, including detailed mapping, significantly increased the confidence of mine-site geology and engineering staff in the geological model and improved operational efficiencies during start-up. This also allowed the engineering and mining team to develop a tolerance for the large fluctuations in daily production grade, with an understanding that budgeted production targets, on a level-by-level basis, were achievable. This paper describes the development of the current interpretation of the deposit and emphasises the importance of a sound understanding of deposit geology. The direct benefits at Emily Ann included improvements in drill targeting, resource estimation and mine planning.

Jan 1, 2003

The Pasminco mine at Rosebery in north western Tasmania is a medium sized underground base and precious metals mine. In April 1992 a major wedge failure of approximately 5000 t occurred in the backs of a main access drive to the 18 level H Lens orebody. This collapse prevented access to 190 000 t of ore which had been scheduled for production in July - August 1992. At the time of the collapse, the mine was in a transition period between mining small pillar remnants of several other orebodies and developing to the new deeper J Lens orebody.The development at this orebody was behind schedule and it was necessary to find a cost-effective and timely alternative to a 75 m bypass drive around the fall area.A Lysaght- Fletcher multiplate steel arch was available on-site from a deferred surface road project and it was decided to use this arch to regain access through the fall area. Due to the danger of continued minor falls, the entire 18 m long, 3.95 m high x 4.5 m wide tunnel had to be assembled in the 4.7 m wide x 5 m high accesss drive and pushed into the fall area as a single unit.

Jan 1, 1993

Discovered in 1954 and mined since 1966, the X41 copper orebodies have produced over 143 Mt @ 3.3 per cent copper. By June 2002 the production from these orebodies had depleted the Mineral Resource to 36.6 Mt @ 2.8 per cent Cu (including 31.5 Mt @ 2.5 per cent Cu combined 2002 Ore Reserve). Mine production will ramp down to cessation beyond ten years. The 2002 Copper Business Study was commissioned to review the status of the Mount Isa copper business and to optimise the long-term strategy of the operations. The study resulted in a vastly improved geological and geostatistical model, and financial studies led to the optimisation of mine cut-off grades. Utilising these new models, a near-mine target generation workshop was conducted by the copper stream geology team. The workshop focussed on exploration for new ore sources and the extension of existing orebodies to supplement the Mineral Resource inventory for future conversion to Ore Reserves. Several prospective targets were identified and the Conceptual Northern 1100 Drilling program was subsequently designed. This paper shall discuss the practicalities of near-mine target generation in Mount Isa, the issues faced when locating and preparing drill sites in a mature mine environment, and the preliminary results of the drilling program so far.

Jan 1, 2003

New knowledge has no economic value unless it can be applied, or æcapturedÆ, as the R&D jargon has it. Australia probably spends more than $500 m per year on mineral industry R&D, distributed amongst the mining companies (IR&D Board, 1997), CSIRO, the universities and others. The investors in this research (industry, and the community via government) will expect some sort of return from their investment. The return will be poor unless the know-how developed in R&D programs can be exploited. This paper explores some of the issues involved in capturing the outcomes of mineral industry R&D in a form which can be exploited for economic benefit, and suggests ways in which it might be done better. It is based on the experience of the JKMRC in conducting applied research in mining and mineral processing and delivering it to the industry. It may seem presumptuous for a research contractor to be telling its clients how to do their job. However, the process of developing, acquiring and implementing R&D outcomes has to be a partnership between provider and receiver, in order for this process to work efficiently. This applies whether the two parties operate within a single corporation (a corporate laboratory and a business unit, for example) or are two entirely independent organisations (eg a mining company and a university). Both partners have a role to play, and the best examples of realising the benefits of R&D almost always involve the open-hearted and skilful handling of this synergy.

Jan 1, 1998