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For the past 40 years, underground trucking using diesel powered or electric wheel driven vehicles, either conversions of surface trucks, or purpose built, has been the preferred means of ore and waste transport in underground mining. The relatively low capital cost, flexibility and requirement for minimal infrastructure means that trucking systems are selected in the early stages of a mining operation. An increase in the carrying capacity of trucking systems with dimensions to operate within existing development excavations is the solution to long term ore and waste underground haulage systems using trucks. The next generation of underground trucks will be low profile articulated trucks with carrying capacities up to 60 t.

Jan 1, 1998

Two key elements in the design of a pastefill or high density backfill system are the preparation of the backfill material and its distribution underground. This paper examines these two areas. Owing to the essentially impervious nature of total mill tailings, preparation of pastefill and high density fill from current tailings involves a physical dewatering process. There are currently three methods available for this process: Vacuum or pressure filters. These represent the ætraditionalÆ approach to the preparation of pastefill. Paste production storage mechanism. This is a thickening/storage mechanism developed with the specific objective of producingpaste/high density backfills. Fluidization. This system utilises silos fitted with simple dewatering devices and nozzles. Recently developed by CANMET, it provides the simplest and most economical approach.This paper describes and compares the three preparation methods, from a practical and an economic point of view. Once the pastefill/high density fill has been prepared and binder added, the backfill must be distributed underground into the stopes. A fundamental factor in the design of a distribution system is the rheology of the material. No two materials will exhibit the same properties, and a sequence of rheological and related testing is required prior to the completion of the design of the underground distribution system. This paper covers the testwork normally required and discusses the fundamental design parameters of pastefill distribution systems. The final section of this paper summarises the use of pastefill at three mines in Canada.

Jan 1, 1998

A blast is designed to completely break competent rock such that it can be economically extracted, and efficiently handled or processed. Efficient breakage of the rock is critical to the success of an operation, and in many operations blast design is optimised to achieve fragmentation, muckpile profiles, and material that is easily excavated. There are inevitably other issues, such as damage to adjacent rock, that should be taken into account when designing a blast to achieve overall optimisation. Some of the key issues with respect to the integrity of the in situ materials adjacent to a blast are identified and briefly discussed in this paper. The potential for damage and the effects of a blast will be strongly influenced by the rock mass properties. This makes it important that site specific conditions and their response to blasting are known. Practical techniques that allow the disturbance adjacent to a blast to be measured with minimum disturbance to operations are described in the paper. Experience shows that, during the blasting process, there is considerable potential to disturb the in situ rock mass adjacent to the blast. In some circumstances a very important objective must be to minimise disturbance outside of the immediate blast area. Measured and observed disturbances caused by blasting to adjacent rock, for various common types of blasting, are discussed in this paper. Blast induced disturbances to the rock mass have been observed in both the near and far fields. These disturbances have the potential to impact on geotechnical design. The geotechnical significance of blast disturbance on a rock mass that is to remain in situ is explored and suggestions with respect to design are given.

Jan 1, 2004

At many locations in Australia the decommissioning of mining operations will require the disposal of excess water. If the water is contaminated its disposal may be restricted by government guidelines. The timing of water disposal may be critical to the schedule of close-out. The uncertainty of the annual rainfall input to the water storage and disposal system may determine the success or failure of close-out. The uncertainty associated with any outcome can be used to determine the reliability of the system, or inversely its risk. The technique of Monte Carlo simulation, using the uncertainty in annual rainfall, is applied to quantify the risks associated with water disposal as part of the requirements for close-out in two case studies. In both case studies it is assumed that water disposal is via evaporation only. The first case study is the Nabarlek operation, located about 270 km east of Darwin. This project is required to complete the engineering work associated with its close-out by December 1995. The second study investigates the situation of close-out for the Ranger Uranium Mine, about 250 km east of Darwin. It should be noted that the Ranger mine was examined as part of the annual update of its contingency rehabilitation plan and the probability of implementing the plan is extremely small. The probability of success for the Nabarlek case varied from less than ten per cent to greater than 95 per cent depending on the management strategy. Four possible strategies were investigated for the Ranger mine with the chance of success varying between 20 and 95 per cent. The estimation of the evaporation rate and the area allocated to evaporation was critical in both cases. By applying seasonally based evaporation pan coefficients determined on site, rather than an average monthly value of 0.75, the chance of success was improved by up to 35 per cent for Ranger. Simulation modelling is able to provide information on the likely response of mine water management systems and the level of risk. This information is required to efficiently plan and manage the disposal of water for close-out.

Jan 1, 1994

By Richards JR, Herbert HK

A basic question in preparing this review was how to define sulphur mineral occurrences as being associated with the Pacific Rim. This question will be reconsidered later. The isotope composition of sulphur- containing minerals may be considered in terms of two primary sources - 1. deep- seated sulphur, devoid of crustal contam- ination with a 634S value near 00/0o and 2. oceanic sulphate which fluctuated in value between +10 and +300/00 over geological time (Claypool et al., 1980). However, minerals have seldom been directly derived from these primary sources as even evaporites have been dissolved and reprecipitated. The marine source is differentiated biochemically and isotopically in recent sediments where sulphide from bacterial sulphate reduction may be significantly depleted in 31S. The question of chemical interaction of ascend- ing magma with upper crustal rocks has become one of degree rather than whether or not it occurs. Mineral deposition is considered increasingly in terms of mixing of fluids and their chemical reactions with rocks rather than direct precipitation from magmas or hydrothermal fluids derived from them.

Jan 1, 1987

By A C. Robertson

Over the past decade there has been continual change in the way that mines have been managed and the component roles of those people who make up the total mine management system. Major issues have included the change in the business structure of mining companies, the change in on-site infrastructure, increased personal liability of managers for the safety and health of employees and increasing social and environmental pressures on managers and their staff. This paper looks at the changing roles of two of the many groups of professionals associated with the mining industry - the equipment supplier and the mining consultant. The profiles of the ACME Group Pty Ltd, suppliers of ventilation equipment and ancillary canvas and plastic products to the mining and construction industry, and Tennent, Isokangas Pty Ltd, Consulting Mining Engineers, are presented.

Jan 1, 1998

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

By Glastras M. V

The presence of arsenic in solutions which result from the processing of many sulphide minerals leads to a need to understand its speciation in aqueous systems and the reactions of those various species. This paper deals in particular with the precipitation of arsenic from aqueous solution in the form of insoluble inorganic compounds in order to remove arsenic from various hydrometallurgical process streams. The solubility and stability of the precipitates is examined. It has been found that many of the arsenic compounds presently used are more soluble than previously accepted and unstable in disposal sites such as tailings ponds.

Jan 1, 1987

By R O. Laidlaw, J L. Mauk

The Coeur d'Alene mining district in northern Idaho, USA is the second largest producer of silver in the world. Mesothermal silver-lead-zinc veins occur in the metasedimentary rocks of the Belt Supergroup with five main types of associated hydrothermal alteration: 1) feldspar destruction, 2) hydrothermal bleaching, 3) carbonatisation, 4) sulfidation, and 5) silicification. Hydrothermal bleaching is characterised by hematite destruction with associated siderite and quartz veins and veinlets, coarse euhedral pyrite and magnetite. Bleached zones envelop both mineralised and barren veins and extend for metres to tens of metres into the wall rocks. Carbonatisation consists of addition of siderite, which occurs as veins, veinlets, stockwork, irregular blebs or spots, and coarsely disseminated grains, depending on the relative distance from the main vein structure. Siderite envelops nearly all mineralised veins, relates to all other alteration types and extends from several metres to tens of metres into the wall rocks. Pyrite and galena alteration dominate sulfidation and are associated with some mineralised veins. Pyrite alteration strongly correlates with siderite alteration and exists in three main forms: a) very fine-grained pyrite flooding, which can extend for metres to tens of metres into wall rocks; b) coarse-grained, euhedral pyrite, which is sporadic and associated with the redox boundary in hydrothermally bleached zones; and c) small isolated zones (6 - 15 cm) of medium-grained, subhedral to euhedral pyrite associated with pervasive siderite alteration. Where present, disseminated galena extends for metres to tens of metres into the wall rocks. Silicification is characterised by veins, veinlets, stringers, irregular patches and variable hardness in siltites and commonly appears in association with hydrothermal bleaching and siderite alteration. Although related to mineralisation, silicification is sporadic and in most places a clear envelope around mineralised veins cannot be identified.

Jan 1, 2001

By A Mulyadi, J Barber, R Golden

The Deep Ore Zone (DOZ) underground mine will be a 25 000 tpd mechanised block cave operation starting production in 2000. The ore handling system consists of a direct truck dumping 54 +74 gyratory crusher, which feeds into an ore bin. An apron feeder below the bin is used to load a conveyor belt. This paper describes the design, sequencing and methodology of the crusher station, ore bin and feeder chamber excavations. The Geotechnical investigation and analysis of the site are also discussed as well as the design, installation and quality control of the long-term ground support methods.

Jan 1, 2000

By Sano S, Ishikawa T, Nagaoka H, Hayashi Y, Hasegawa M

The stirred mill is regarded as one of the most efficient devices for micronising materials and has come to be actively used for preparation of fine particles. Recently, the demand for ultrafine particles was increased in many kinds of industries. In this paper, autogenous grinding to get submicron particles based on mutual friction feed material has been carried out using a stirred mill. The mill used was made of stainless steel and its volume was about 5.5 litres, and has 12 impeller blades. Sample used was limestone. In the present work, two operating parameters such as stirring speed and feed size of limestone were considered. The ground products were sieved in the size range from feed size to 325 mesh (45 lun), and from 45 to 0.17 pm the size distributions were measured by a laser diffraction and scattering method. The progress of grinding was evaluated by the increasing amount of submicron particles in products. As a result, the rotational speed of impeller with the minimum energy consumption to produce submicron particles was observed. It was found that the autogenous grinding with a stirred mill is an effective method for producing submicronized limestone.

Jan 1, 1993

By K Nguyen

The advances in computerised processors and digital microscopic imaging have enabled more studies that attempt to quantify textural information from rock images. However, a texture classification system designed for geometallurgy has always been challenging, as it combines general image analysis techniques and specific texture classifications in terms of the size, shape and orientation of mineral particles. In this paper, a novel texture analysis technique using grey level radial shell association (GLRSA) and spectral angle mapper (SAM) to discriminate between different geological images is outlined. The technique can be applied in routine analysis and characterisation of mineralogical and textural attributes which may correlate with variability in mineral processing behaviours. Using this texture analysis technique, a set of small texture reference images, a texturelet reference library, has been identified from a suite of drill core images. Rock types are classified according to the proportion of each texturelet type recognised. The library is site specific.CITATION:Nguyen, K, 2013. A new texture analysis technique for geometallurgy, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 187-190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By J Emslie

Newmont AustraliaÆs Callie Underground Gold Mine is located on the Dead Bullock Soak Mining Lease, approximately 600 km NW of Alice Springs, NT, in the Granites-Tanami Goldfield. Dead Bullock Soak is part of NewmontÆs Tanami Operations, which also include the Granites Gold Mine and processing plant, Groundrush Open Pit and Tanami Mill. Callie is a world class Proterozoic gold deposit; production to date is in excess of 1.7 million ounces, with an additional Proved and Probable reserves at the end of 2002 of 10.8 Mt at 6.3 g/t. Gold mineralisation at Callie occurs in thin (1 - 30 mm) steeply dipping quartz-chlorite sheeted vein system that cuts across a 40¦ plunging folded sequence of medium to fine-grained metasediments. While the vein system is highly continuous, the gold distribution is highly variable and is controlled by the interaction of lithology, alteration, structure and vein density. The mineralisation is commonly coarse-grained and has a relatively high nugget effect, consequently the orebody is problematic to estimate and shows a high degree of sensitivity to drill hole density. Resource modelling at Callie is an example of a geologically driven model that has evolved with increasing data and understanding. Lithological and structural models are employed to define domains within which the grade estimation is undertaken using multiple indicator kriging. This gradual model evolution impacted greatly on the selection of the mining method. Uncertainty in the estimation of the orebody was a significant factor that led to sublevel open stoping with cemented aggregate fill being adopted as the mining method to improve extraction selectivity. Callie often shows strong positive reconciliation compared to the mill. The mine geologistÆs face the challenge of limiting the degree of underestimation of the core of stopes whilst ensuring that stope boundaries are not conservative. This can only be achieved through the mapping of subtle geological features in order to confirm the orebody model. The increased use of the geological mapping has improved our understanding of the controls on mineralisation and has been extended into the development of new models for near mine underground exploration.

Jan 1, 2003

By P Crorkan

Within the framework in which future exploitations for Codelco-Chile Divisi=n El Teniente are situated, regarding the deepening of its reserves and the geotechnical problems that affect their recovery, it becomes strategic to evolve with new variants, which make deep mining possible. Codelco ChileÆs Divisi=n El Teniente is progressing within its long-term planning the exploitation of a sector called Esmeralda, which includes its removal through the gravitational caving method (panel caving). It is planned to use pre-caving, which basically consists of developing and undermining the undercut level, without having developed the infrastructure of the production and transport levels. This is carried out in order to achieve a better redistribution of the stresses, thus obtaining higher quality in the infrastructure development of these levels as well as less risk. The extraction reserves for this area, estimated through the opportunity cost selection criteria, were determined at 348 million tons with an average grade of 1.014 per cent Cu. The project carried out geological and geotechnical studies in order to prevent the geomechanical risks of the sector to be exploited, which is a site conformed totally by primary ore. Lithologically, it occurs mainly in Andesite, located at the western limit by Brecha Braden Pipe. There are also varieties of porphyries and hydrothermal breaches of anhydrite. The Esmeralda Mine production program will increase from 4000 tpd (average) in 1998 to its 45 000 tpd rate of production estimated for the year 2005. The approved investment for the period 1995 to 1999 is $US 150 million, out of a total $US 213 million for the project. At feasibility study level and before the project, it showed a Net Present Value of $US 342 million, an Internal Rate of Return of 37 per cent and an IVAN indicator of 2.3 for a ten per cent discount rate and a copper price of 100 US cents/lb.

Jan 1, 2000

By A J. Moore

To control the airblast from blasting to regulatory limits at environmentally sensitive sites near the Collinsville Coal Mining Operations, it has been necessary for Thiess Mining to incorporate a wavefront reinforcement analysis model in the predictive environmental airblast design. Controlling airblast from cast blasting 70 m high faces with 2000-3000 kg of explosives per hole within 700 m of houses presents a considerable challenge to the blasting personnel. This paper describes the model used and summarises the results of an investigation designed to quantify the increase in airblast indicated by wavefront reinforcement diagrams to further calibrate the model for future prediction.

Jan 1, 2004

By J Chßvez, J Rosa del Castillo, J Rui

Environmental Impact Assessment (EIA) and Feasibility Studies (FS) were carried out to evaluate the potential use of treated acid mine drainage (AMD) occurring at the Kingsmill Tunnel in the Central Andes of Peru. The 11 km long tunnel drains the underground works of the Morococha Mining District and discharges about 1.25 m3/sec of AMD directly into the Yauli River in the Amazon Basin. The communities living downstream cannot use the Yauli River water due to its low pH and elevated concentrations of metals (eg Cu, Zn, Fe, Mn, As, Cd) and sulfate. Studies carried out for this project included technical feasibility, EIA, economic viability and social impact assessment phases. During the æTechnical FeasibilityÆ phase, the treated AMD was produced by simulating a high density sludge (HDS) lime neutralisation/ precipitation process and was evaluated for various potential uses. Mining companies located in Morococha, in particular Centromin Peru SA, and the Water Works Company of the City of Lima (Sedapal) collaborated with Golder Associates during the studies. The Canadian International Development Agency (CIDA) provided the financial assistance. The results of the physical, chemical, biological and toxicological analyses demonstrated that the AMD could be sufficiently treated to be potentially used to supplement the drinking water supply of Lima, and for agricultural (eg irrigation and livestock) and recreational purposes. Process design and scale-up parameters were also determined for implementation of the full-scale treatment facility at the site. The use of the treated AMD as a drinking water supplement would be economically feasible.

Jan 1, 2003

By Collins L

The commercial success of a mining project can be strongly influenced by the business activity which takes place away from the mine site. The project revenue is determined by marketing success which results from persistent research and full realisation of suitable products and by-products and appropriate upgrading achieved in conjunction with proper material security and insurance. Significant costs of transport can be optimised, protection of the environment carefully managed and skilled employees acquired as a valuable asset. Working capital requirements are often substantial and should be carefully established and financed, possibly by special contractual arrangements for product sales.

Jan 1, 1997

By A Buckingham, R M. Hancock

The underground Sunrise Dam gold mine commenced in October 2003 to extract ore from a series of orebodies with various dips, widths, and ore grades over a strike length of 1.5 km. To successfully operate flat stopes it was identified that a means to extract ore left behind after blasting in stopes with dips ranging from 15 to 40 degrees was needed. Various options were available, which included a bulk water cannon, hand held high-pressure water jet, remote controlled small dozer, several mini excavators and finally a specialised remote controlled excavator from the demolition industry. Trials were commenced for the bulk water cannon option in 2006 that proved that the concept worked, however, the system was too cumbersome to set up for use in cycle with production. Hand washing down using mine (low pressure) water with a two-inch bullhose proved of limited value. The small, one metre high remote controlled dozer as used in South Africa was reviewed, but the steepness of most of the stopes precluded this machine. The hand held high-pressure water jet option is still being investigated; with safety factors still being addressed. Several mini excavators were trialled to clean out the flat stopes with generally poor results, the machines being either too large to fit in the drives and pull ore down or too small with too short reach to effectively and efficiently pull ore out of the stope. In early 2007 a Brokk 330 remote controlled excavator was trialled on site with the low profile of the machine and unique arm configuration proving an effective tool for pulling ore from the footwall of short, flat stopes. A Brokk 330 remote controlled excavator was purchased in late 2007 and is currently in operation.

Jan 1, 2008

By Penny T. G

BHP Diamonds and their joint-venture participants DiaMet Minerals, Chuck Fipke and Stewart Blusson are currently developing Canada's first commercial diamond mine in the arctic barren lands of the Northwest Territories (NWT) of Canada. The paper reviews the early history of the project leading up to the discovery of the first kimberlite pipe in September 1991, diamond exploration techniques and the subsequent advanced exploration and development work carried out at the site. In many aspects, this exploration work represented a development project in itself. Coinciding with the advanced exploration work, the project team prepared an Environmental Impact Statement (EIS) and went through federal review of the project at the highest level. External affairs strategies regarding the federal review and aboriginal land claim issues were crucial components to the approval process. Upon approval in principle by the

Jan 1, 1997

By Newman H. A

Goldsworthy Mining Limited is currently mining iron ore at an annual rate of 7 million tons from several small orebodies, each of which exhibit wide variations in iron, phosphorus, silica and alumina contents. Each orebody is mined at its average ore reserve grade and therefore mine planning and grade control techniques have had to be tailored to achieve a constant production blend.

Jan 1, 1973