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Among the various methods of thick-seam mining already well-tried in practice longwall caving with extraction of a single slice, as thick as possible, abandoning the top and/or the bottom coal, seems to be the most suitable one for the Australian coal mining industry. The production units of the future should be equipped with heavy double-drum shearer-loaders, wide armoured conveyors, (with one or two central chains) and shield support. Material of this type has been developed for seams up to 6 m thick. Output figures of more than 6,000 tROM/d from a single face can be looked upon as a quite realistic expectation. The problems of co-ordinating such large production units with the whole layout of the mine are discussed. The factors to be taken into account in the planning work and for preven- tion of mine fires caused by spon- taneous combustion are dealt with. For economic reasons the highest possible utilization factor of the very expensive equipment must be aimed at. Furthermore, the seams or parts of seams to be extracted should be carefully selected.

Jan 1, 1976

The medical evaluation of the health effects of dust exposure in the mining industry should be based on the premise that the results of the medical examinations will be considered in relation to the previous history of exposure to dust.(l) To this end the Mines Regulation Act and the Regulations under that Act in West- ern Australia provide for: the prime responsibility for dust sampling to rest with the mining companies; the appointment of a Ventilation officer by each mine and the sampling and record- ing by him of dust and toxic gases in work places at three monthly intervals, or more frequently as required; the appointment of a Mines Medical Officer who shall make provision for the medical examination of persons and the prevention of occupational diseases; the appointment of a Ventilation Board, consisting of the State Mining Engineer, the Senior Inspector of Mines for the State, an Inspector of Mines having specialised training in ventilation tech- nology, a medical practitioner having specialised experience in occupational health problems relevant to the mining industry, and a Scientific Officer having duties under the provisions of the Clean Air Act, 1964;

Jan 1, 1979

By McDonald E, Clifford PJ

A mine planning system comprises all elements necessary to carry out the full range of mine planning activities from exploration to operations control. The application of computers as part of a mine planning system has great potential for increasing the efficiency and quality of mine planning and reducing its cost. The introduction of computers to mine planning in open cut coal mines has been hindered by the cost of processing the large databases associated with large coal deposits and the inherent inconvenience of performing an interactive process on a time-shared computer. A dedicated computer is ideally suited for the purpose but reasonably priced micro/ mini-computers until recently have not had the capacity to store the volume of data or the processing capability required. Recent hardware developments have cleared the way for the development of truly interactive mine planning software, covering the complete range of activities associated with open cut coal mine planning, incorporating them into a single system using a common database. The MINEMAP System is a hardware and software package tailored specifically for mine planning of open cut coal mines and is an example of such a system.

Jan 1, 1983

An improved method of sample recovery for use with rotary percussion drilling has been developed. Cuttings can be recovered continuously from either dry or wet drilling, and the recovery under dry conditions is seldom below 99% of the cuttings brought to the surface by the rig. The system is designed for use with top drive drilling rigs using flush-jointed drill rods. The key feature of the system is a self-aligning mechanical seal around the drill rods. The sealing unit is removably fixed to a collar section of cas ing. the cuttings are recovered in a plastic bag attached to the bottom outlet of a cyclone. A valve at the bottom of the cyclone permits the cuttings representing various depths to I,e recovered separately for examination eind 0(iclysis. [u the Iron Monarch quarry, two percussion holes were drilled to depths if 30 metres and 28 metres using the unproved sample recovery system, and diamond drill holes bored 1 metre from each percussion hole. Samples from each hole were sectionalized over metre intervals and analysed for iron, silica, alumina and loss on

Jan 1, 1976

By Y Potvin

Risk assessment in the mining industry is currently a topic of great interest with risk methodologies being increasingly applied beyond the traditional areas of finance and feasibility to analyses of risks due to various physical hazards including chemical, electrical, mechanical and geotechnical sources. The application of risk analysis and evaluation techniques to the management of personnel safety is being promoted by both industry and regulators but, particularly for geotechnical hazards, often there are inadequate databases for a meaningful quantitative calculation of risk. In Western Australia over the decade 1987 - 1997, the annual fatality rate for underground mining has averaged at approximately 1.3 in 1000 employees with rockfalls/rockbursts accounting for over half of these deaths (Prevention of Mining Fatalities Taskforce, 1997). Recent improvements have been made since this time, perhaps halving the annual fatality rate, mainly due to industry improving ground control measures and implementing various recommendations from the Prevention of Mining Fatalities Taskforce (1997). However there still remain a large number of unknowns when trying to address the complex area of geotechnical risk in mining. Risk calculations require information about the source of the hazard, the people or assets exposed to the hazard (the æelements at riskÆ) and the effects on these vulnerable elements if the hazard actually occurs (the potential consequences). To date, little information has been available on the exposure of mining personnel and equipment to underground hazards other than occupational safety studies on chemicals, heat, dust, etc. This paper concentrates on underground geotechnical risks and presents a data collection and rating system for the exposure of both the underground workforce and equipment to rockfalls and rockbursts. The methodology considers exposure times, personnel protection levels and hazard proximities to give exposure ratings for the major underground mining activities and hence rate different locations within a mine. This exposure methodology is then applied to the workforce and production/ development cycles in an actual WA underground mine, creating a snapshot map of differing levels of personnel exposure across the mine.

Jan 1, 2003

The sole reason for a mine to exist is to extract the finite mineral resource. Accurate grade control is critical to the economics of any mine. If grade control is not optimised, then no matter how good the downstream processes are, the full potential of the operation will not be realised. The detailed implementation of grade control varies but typically consists of sampling and assaying to determine the location of the ore zones. A lot of time, money and effort are spent defining the location of the ore as accurately as possible à but then it is blown up! The effect that blasting has on grade control is rarely adequately accounted for when the rock is excavated because there has never been an accurate and practical method for measuring blast movement. This paper draws on over six years of research into measuring and understanding blast movement, which started at the Julius Kruttschnitt Mineral Research Centre (JKMRC) of the University of Queensland. The research has made a unique contribution to open pit blasting by helping to develop a practical tool for measuring blast movement, which was then used to improve the understanding of three-dimensional blast movement dynamics. However, these achievements would be of largely academic interest without taking the final step of using this technology and knowledge to account for blast movement by translating the ore polygons in response to the measured movement vectors. This paper provides an overview of blast movement but focuses on one site where blast movement was measured during three separate periods, with significantly different orientation of the mineralisation on each occasion. The theoretical ore loss varied from nine per cent to 24 per cent. The differences are primarily due to the orientation of the ore polygons relative to the direction of movement. The optimum grade control solution is a combination of accurately accounting for blast movement and designing appropriate blasts.

Jan 1, 2009

Feasibility is a value improvement process for projects. At any stage in project development, a feasibility study can be undertaken, but although the scope generally remains unchanged the extent of detail and level of accuracy usually increases with time. The main scope elements are a business definition, project description and an execution plan. The studies are designed to assess the potential of the project and to secure funding for on-going examination. Invariably, the investigations loop back to earlier stages to establish more appropriate development criteria but a critical stage is reached when a project construction decision is requested. This feasibility study requires very detailed presentation and analysis to a higher accuracy for the owner(s) and their potential lender(s).

Jan 1, 1997

Metsim is proving to be a powerful tool when designing a heap leach operation. The most useful outputs arc determining the fluctuations in pregnant solution recovery rate, make-up water rate, gold recovery rate. and pond levels. Detailed data are needed for input: a pad loading schedule, a mining rate schedule for each ore type, column leach test data for each ore type, column tests on water dynamics (ie hourly flow-out versus-in during saturation and drain-down), monthly rainfall and evaporation data, and proposed pond dimensions. These data allow 'what if' studies on application rates, leach rates, loading rates and other variables of interest. Examples will he given of modelling both a rectangular pad and a valley fill operation.

Jan 1, 1994

A laminar-flow furnace was used to study the combustion of four flotation concentrates (chalcopyrite, pyrite, galena, and sphalerite) in air at temperatures up to 1400¦C. A special- Iv developed two-colour pyrometer was used to measure the temperature of individual chalco- pvrite and pyrite particles as they underwent combustion. Chalcopyrite and pyrite ignited with very high rates of reaction at air tempera- tures above 480 and 600¦C respectively, forming molten products. Galena and sphalerite required temperatures in excess of 700 and 1200¦ respect- ively to attain equivalent rates of reaction. The high rates of reaction for galena and spha- lerite were caused by vaporization. Temperature measurements for chalcopyrite and pyrite are reported here, together with vaporization measurements for chalcopyrite, galena, and Sphalerito

Jan 1, 1980

A pilot plant has been constructed for the low temperature carboni-zation of Wallarah (N,S,W6) coal at the rate of 300 pounds per hour. The plant was built and tested at Australian Mineral Development Laboratories for Broken Hill Pty, Ltd. Char product was required within the specifi-cation 15.5 `S' 1 per cent volatile matter. The design was based c atz an entrained state carbonizer developed by Parry and U.S. Bureau of Mines co-workers at Denver, U.S.A. The method involved the carbonizatioan of fine coal by entrainment with air in an externally heated reactor.. The heat required for carbonization of tits coal was supplied to the be, both through the reactor walls and also by internal cambustion of products .

Jan 1, 1963

By Jackson E

The general level of awareness amongst members of the professions that they are faced with an increasing number of claims for breaches of their professional duty was dramatically heightened by the decision of Rogers J. at first instance in Cambridge Credit Corporation v Hutcheson (1985) 3 ACLR 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 found in the fact that this decision was overturned on appeal, for that result rested on the issue of 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.

Jan 1, 1989

By Quast K. B

Laboratory batch rod and ball milling tests were conducted on samples of Heavy Medium Separator (HMS) sinks from Renison Tin Limited. The product size distributions for this heterogeneous material were very different to similarly sized homogenous material previously reported by the authors. The effects of pulp density on product size distributions were only evident at pulp densities greater than 80 per cent solids. At high solids density, the major weight distribution product peak fell and broadened indicating less efficient breakage, particularly for rod milling. Tin distribution in the ground products was also affected by pUlp density, and there was always less cumulative per cent tin than cumulative per cent weight, ie there was no tendency for cassiterite to slime down to 10/lm.

Jan 1, 1995

By S Porter, R Woodall, N Weeks

Nelsen, Porter and Wilson (1996) provided some preliminary concepts for the design of the Melbourne City Link tunnels. At that time, the City Link project was in the early design phase whereas now it is nearing completion. This paper provides details of the actual design adopted for the various sections of the tunnels as well as some commentary on the design process. The tunnels form a critical element of the project and the design of both driven and cut and cover tunnel sections is a significant factor contributing to successful project execution. Geology, hydrogeology, site constraints, traffic management and program were important design inputs. Design for the cut and cover sections in particular varied significantly in response to these differing inputs.

Jan 1, 1999

The Snap Lake Phase I project initiated a subsampling campaign on the material (kimberlite/metavolcanic/granite) mined and treated for diamonds. The campaign was aimed at determining the optimum subsampling program to subsample the feed to the bulk sample plant (BSP) for the duration of a sampling campaign. This paper describes the application of GyÆs formula for determining the subsample size and other good sampling practices to determine this subsampling campaign. Three main issues are discussed: the use of a hammer sampler to sample off a moving conveyor and the practical experiment to determine the optimum subsampling program; bias introduced by laboratory equipment including two sizes rotary splitters; and variability of the feed material to the BSP over time.

Jan 1, 2005

By P T. Hick, T J. Cudahy, M S. Caccetta

Dust derived from mining and handling of ore has been identified as a major concern for the mining industry in Australia and may be critical to the future viability of some resource industries (CSIRO, 1999). Operational techniques to derive accurate measurements of anthropogenic dust on vegetation and infrastructure are necessary for the long-term management and monitoring of the environment surrounding mining operations. Airborne hyperspectral VNIR-SWIR systems can potentially provide these monitoring data. This paper outlines a method developed for deriving quantitative measurements of dust quantity on mangroves using remotely-sensed airborne hyperspectral data. The results show that it is possible to detect and quantitatively map iron oxide dust distribution using properly calibrated airborne visible to short wave infrared (VNIR-SWIR) data.

Jan 1, 2002

By E McLean, J Fleay, M Davis

Performance testing is often used by project owners and financiers to provide protection from, or assessment of, technical aspects of project design, procurement, construction and commissioning. The performance tests can range from comprehensive performance warranties relating to process performance and production in the case of lump sum turn key (LSTK) projects to less onerous demonstration tests for cost reimbursable contracts. This paper will discuss performance testing from both the contractorÆs and ownerÆs perspectives and focuses on: when performance tests are required, what type of performance test/warranty is optimum for each type of project, and how project performance should be evaluated. The requirement for performance testing can be driven by the project financiers, particularly in the case of smaller resource development companies. In such cases, differentiation between ownerÆs risk and contractorÆs risk can become contentious. At the other end of the spectrum, larger mining houses may choose to heavily influence the engineering and design process with the contractor supplying services on a reimbursable basis. In that case, the performance testing process is often limited to demonstration tests that validate performance for the ownerÆs corporate governance requirements. This paper was prepared due to the lack of published benchmarking of performance testing and the resultant differences in expectations between a contractor and a project owner that often surface late in the contract negotiation process. The paper provides a checklist of requirements for both the owner and the contractor that may be used to provide æcommon purposeÆ early in the contract negotiation process.

Jan 1, 2007

By A S. Bamber

Mining is the oldest industrial practice on the planet with a history dating back over 3000 years. Since the early iron age ores have been extracted for use in a variety of contexts by humankind, from domestic to military, transport and more recently for complex industrial applications. Mineral exploration and extraction has evolved from the early exploitation of primary metal occurrences in relatively small quantities such as iron, gold, coal and copper, to the bulk mining and extraction of highly complex polymetallic oxides and sulfides today. Since the industrial revolution, mining practice has evolved substantially to support an increasing range and quantity of required metals and to accommodate the increasing scarcity of high-quality sources of these metals. A common response to the increasing scarcity of mineral resources has been to expand production through simple economies of scale, thus diluting fixed costs. This approach, however, is increasingly ineffective in the face of current trends, that include increasingly complex mineralogy, increasing pressure on environmental footprint - energy in particular, and increasing scarcity of capital for the construction of presently popular æmega-minesÆ. This paper examines historical trends and current practice in mineral exploitation in the light of the current global revolution in social, environmental and economic values as the projects move towards a vastly different topology for the industry for continued success in years to come.CITATION:Bamber, A S, 2012. The mining industry needs to be shaken and stirred, in Proceedings Narrow Vein Mining 2012 , pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

By Quast K. B, Newell R, Caterford J. H

The most common reason for gold-bearing deposits being refractory is the presence of sulphides; in many cases these interfering minerals contain arsenic, antimony, or other environmentally-sensitive elements. A number of processes have been proposed or developed for pre-oxidation of interfering minerals. In most cases developers have focussed on gold recovery and capital costs, with relatively little data on the deportment or form of these potentially harmful elements. This paper surveys recent work connected with pressure pre-oxidation processes. Data from pilot plant treatment of refractory gold materials, using the nitric acid Redox process, is discussed along with the attendant flowsheet and engineering implications. Four refractory gold-bearing materials have also been tested at the University of South Australia for arsenic and antimony deportments.

Jan 1, 1991

Thank you for that introduction and especially thank you to the organisers for inviting me. I've had a considerable interest in this area and I've had the advantage of an education from Neil on the subject of offering documents as a result of our collaboration together on the Securities Information Review Committee.

Jan 1, 1989

Benchmarking of mining operations has been in vogue for a number of years: it seems teams are forever flying around the world to try to understand what other operations are doing. However, unless a benchmarking exercise involves data gathering at a fundamental level and a rigorous analysis process is applied, the trip will be nothing more than industrial tourism. When benchmarking is performed thoroughly, the range of comparisons that can be made is extensive and informative, and need not be restricted to sites with similar conditions and equipment fleets. This paper describes the detailed and rigorous process for benchmarking used throughout AMC benchmarking studies. The paper demonstrates how, through drilling down to the underlying drivers, the often heard cry of æyou canÆt compare us, weÆre differentÆ can be overcome. Included in the discussion are a number of significant issues that have been identified during AMC benchmarking studies. The paper then considers the types of opportunities that have been identified and the potential for improvement. The paper concludes with a discussion of the implications for planning, measuring and management of operational performance.

Jan 1, 2003