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Compared with modern longwall coal mining systems, automation has not been developed very far in the underground metal minin industry. One of the main reasons for this is that present har rock mining systems do not produce ore with a controlled degre of fragmentation. The often poor fragmentation from the stopescauses large extra costs and precludes material which 1-ends itself to automationThe paper investigates the possibility c technology for automatic loading and trapconveyor belt to a shaft dump pocket. With this concept, it will be necessary to control the maximum fragment size by careful blasting design. The degree of fragmentation will have to be finer than is common to-day. The study shows that the belt conveyor mining con-cept with controlled fragmentation may be economically competitive with conventional cyclic loading and transport, even for an annual production as low as 0.5 mill. tonnes.. Fragmentation design and cost calculations have been based on a combination of the Kuznetsov relationship between blasting parameters and mean frag-ment size, and the Rosin-Rammler formula for fragment size distribution.

Jan 1, 1985

Between, 1980 and 1984, the demand for non- ferrous metals in the free world grew annually by 1.5 per cent for copper, 0.4 per cent for lead, 1.4 per cent for zinc, and 2.5 per cent for nickel. The growth rate decreased substantially compared to the rate experienced before 1980, and was far lower than the GNP growth during the corresponding period. The main reasons for this are considered to be 1. resource-saving efforts by industrialized countries resulting from the first and the second oil crises, 2. saturated demand for durable consumer goods, and 3. substitution of non-ferrous metals by new materials such as optical fibers.

Jan 1, 1986

As modern techniques of Petroleum Exploration and Development are rela-tively new in Australia,2 the alien terms "Mud Logging" and "Core Analysis" will bear explanation. Mud Logging and Core Analysis are two of the Petroleum. Industryts most useful "tools" in the successful search for, and development of, commercial oil and gas deposits. Modern Mud Logging could be more accu-xately termed "Drill Cuttings and Mud Gas Analysis". Presently, mud-logging has its greatest application in exploratory wells where subsurface geologic control is at a-minimum.

Jan 1, 1962

This paper forms part of a series of papers relating to the Melbourne Underground Rail Loop and presented to the Fourth Australian Tunnelling Conference in Melbourne, March 1981. The Design of Electrical and Mechanical Services in Museum Station and adjacent Running Tunnels and their relation to Rail.wruy Operation through the Loop are described. The descriptions, while specific to Muscrio Station, are generally representative of those being provided at Parliament and Flagstaff Stations. The Museum Station comprises some 6500 square metres of platform and track area, 5000 square metres of booking hall concourse and entrances and 1200 square metres of offices and plant rooms. The Mechanical and Ilectrical Services for this complex are .imilar in many aspects to those of a large !.gr.hrise city building, but in general the i::;ign is directed more strongly towards :.arety, durability and reliability, and subject to many restraints imposed by L'mitations of space and accessability.

Jan 1, 1981

One common public perception of mining is that financially it is an extraordinarily risky business. Another and contrary view, in certain circles, is that price risk and other financial risks can be relatively easily removed or shifted by a number of schemes or devices. In reality, beyond the orebody discovery stage, mining need not be any more risky than most heavy industrial businesses. Nevertheless, as stated by Rappaport, (1986): Risk is a parameter of central importance in establishing the economic value of any asset. The level of risk is determined both by the nature of the firm's operations and by the relative proportions of debt and equity used to finance its investments. These two types of risk are commonly referred to as 'business risk' and 'financial risk' respectively. The term financial risk is used somewhat more loosely herein to recognise the reality that any risk inadequately addressed in the design, construction and operation of a mining project can have significant financial consequences; usually negative. For instance, a specific area of business risk in mining is often called technical risk which definitely has severe financial consequences if not managed correctly. The various risk shifting, hedging and risk management tools available all have their place and range from merely useful to almost indispensable. However, in the long-term, financial risks are maintained at acceptable levels by the application of sound, more fundamental business management principles. There are many with a vested interest in perpetuating a perception that the conceptual foundations of sound management practice are extremely complex. In reality, most management concepts are prosaic, but their application requires incredible discipline and hard work. There is no magic formula or 'silver bullet'. It appears that a company whose activities are restricted to mining can analyse the range of risks specific to mine development and operations more clearly than companies in which mining is just one of many businesses. The almost universal failure of large oil companies in the mining business is probably the best example of lack of any clear comprehension of fundamental business characteristics and risks. Conversely, in regard to risk management, choosing to be in other business as well as mining does nothing to reduce the risks of the mining business. The individual shareholder can probably make such 'diversification of portfolio' decisions better than most management teams. It could be argued that diversification across a number of disparate businesses may actually increase overall corporate risk due to lack of management concentration and focus. These differences between the perceptions of financial risks and the realities in mining need to be further elaborated in relation to some uncompromising business concepts.

Jan 1, 1994

Projections of metal requirements for Japan and the United States indicate growing competit- ion for Australia's mineral output and a critical need for continuing discovery of new reserves. These projections may be modified by economic, social and political controls - the most import- ant factor probably being a shortage and the high cost of risk and development capital. Changing ownership patterns toward joint ventures and increased state participation are anticipated. New developments in global tectonics and metallogeny delineate favourable zones for ex- ploration and permit establishment of priority search areas even in regions of poorly known geology. Declining ore grades and special character- istics to meet technological requirements may modify identification and evaluation criteria. A broad approach considering all environments of concentration within the geochemical cycle is re- quired within any metallogenic province. The exploration geologist must be able to integrate geological theory, mining technology and financial analysis to establish well defined exploration objectives, in terms of economic and geologic models, in concept-oriented programmes.

Jan 1, 1973

By G R. Hancock, D Verdon-Kidd, M J. Saynor, J B. C Lowry, T J. Coulthard

The ability to simulate the stability of post-mining landscapes over time scales ranging from decades to millennia is a critical element in the assessment of closure designs for uranium mines. Landscape Evolution Modelling (LEM) technologies provide a means to simulate and assess the long-term geomorphic stability of a conceptual rehabilitated landform for periods of thousands of years. However, a major issue with simulations derived from long-term modelling are the limitations associated with the data inputs. Specifically, simulations which utilise historic rainfall data only represent the variability of rainfall events that have occurred over a relatively short period. Consequently, these simulations run the risk of not accounting for the full range of rainfall variability that might be expected over an extended period of up to 10 000 years. Therefore, for this study a probabilistic approach was adopted to generate a stochastic synthetic rainfall data set to produce a series of unique rainfall scenarios, each representing a simulated period of 100 years. Importantly, utilising such an approach allows uncertainty in predictions to be better accounted for and provides a range or probability of likely outcomes.In this study, the effect of ten individual rainfall scenarios are assessed in terms of their impact on the predicted erosion and denudations rates produced by the CAESAR-Lisflood LEM for a conceptual rehabilitated landform of the Ranger Uranium Mine (RUM) in the Northern Territory of Australia, focusing on the Corridor Creek catchment (Figure 1). While legislation requires this site to be erosionally stable for at least 10 000 years (Commonwealth of Australia, 1987), here the focus is on the first one hundred years of landscape evolution, as this is the period in which erosion is expected to be higher, with limited vegetation cover or pedogenic development in the initial decades after rehabilitation. It is also the period where the drainage pattern is set.CITATION:Lowry, J B C, Verdon-Kidd, D, Hancock, G R, Saynor, M J and Coulthard, T J, 2016. Application of synthetic rainfall data to long-term modelling of a rehabilitated landform, in Proceedings Life-of-Mine 2016 Conference , pp 75–79 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Clark T. M

Underground coal mining involves the disturbance of natural strata stresses formerly in equilibrium, the production of noxious and flammable gases and dust which can be both an explosion and a health hazard. It involves also the use of heavy, large equipment operating on natural floors and in confined spaces. Such operations are required to be carried out under artificial light. Much of the easier won coal, that is the shallower coal, from this State has already been extracted and in future workings will be required to go deeper. As the depth increases strata pressures will increase, gas production is likely to be greater and the production of dust will also increase. A further problem which has not yet reached significant proportions in Australia is the potential rise in working temperature. This will be occasioned not only by the use of large items of equipment which themselves generate heat, but due also to thermal gradients as the depths increase. The need for better employee training is now being widely recognised throughout the industry. Under present highly mechanised conditions new employees should not be required to work with or near heavy mobile machinery without proper training

Jan 1, 1976

By Teague JK, Read HW

The relationship between the maceral composition of coal and the strength of the coke produced from that coal has received a great deal of attention in recent years. Studies using two Bulli Seam coals, and blends of Bulli and Wongawilli Seam coals, from the Illawarra Measures of the Southern Coalfield of New South Wales were carried out. The optimum range of vitrinite was found to lie between 45% and 60% (mineral matter free). Above and below this vitrinite range coke strength deteriorated. I Coke strength indices increased with rank and the optimum vitrinite content increased with an increase in rank. These changes will require confirmation as trends by testing a third level of rank. It was noted that vitrinite content decreased with an increase in the specific gravity of separation of the coal. . T Use of- petrographic analyses will increase confidence in choosing coals for coking, provided the coals are well known. Such analyses offer the possibility of greater flexibility in coal purchases and the possibility of producing a marketable blend from coals, which have limited market potential. Critical base coals for blends can be conserved. Significantly more work is required before coal reserves can be utilised to optimum advantage. This work would require extension of-the studies discussed in this paper and, in particular, the testing of a wider range of rank.

Jan 1, 1970

Efforts to stabilize international markets in commodities have gradually intensified during the course of this century in keeping with the grow- ing complexity and interdependence of the world economy and the increasing involvement of government in economic activity. Successive Australian Governments have con- sistently supported the concept of commodity agreements and arrangements in an effort to lessen short term fluctuations in price and to moderate the boom/bust conditions which tend to charac- terize production and trade in many commodities. The objective is to stabilize price at a level which equates supply and demand over the life of the arrangement. Such action involves a degree of market inter- vention and government involvement in the inter- national trade in the commodity concerned; the acceptability and desire to foster such arrange- ments varies from country to country depending upon attitudes to market intervention and man- agement. However attitudes, even among those opposing commodity agreements, have under- gone a major reversal in this century. Before the first world war, such intervention as existed almost entirely involved the physical producers. There was almost no government involvement and at that level most regarded commodity agree- ments as neither desirable nor practical. However government regulation of such activities as pro- duction and marketing of food during World War I, coupled with post-war shortages, followed by overproduction and the crash in prices during the Great Depression, stimulated producer gov- ernment interest in commodity market regulation. Consumer governments took a little longer and with a few exceptions, it was not until the post World War II period, that the fear of shortages of basic commodities brought some consumer countries to accept the concept.

Jan 1, 1978

The techniques used in evaluating gold placers and in recovering gold therefrom are briefly reviewed and critically assessed, relative to the estimated and actual recoveries from many operations. The discrepancies between these quantities can be significant and sometimes disturbing. The coefficient of variation for the annual percentage recoveries, relative to the estimates, is in excess of 10 and commonly above 20 . The difficult- ies in evaluating placers are recogni- sed both in the gathering of meaning- ful sample data and in the derivation of estimates. There are deficiencies, perhaps insurmountable at reasonable cost, in the techniques used to derive an estimate and in the gold saving devices usually employed. There is a subconscious trend to use recovery as a check on the estimate. The industry could have extracted more information during the evaluation and working of deposits in order to fully characterise them and in order to quantify metallurgical efficiency. There is a place for other prospecting techniques, particularly geophysical, in placer evaluation and a need for more appropriate and sophisticated

Jan 1, 1976

Immigration has influenced Australia's development more than any other factor. As well as being critical to our economic growth and development, it has made a major contrib- ution to our population growth, to the richness and diversity of our society and to our inter- national relations. Migration from the United Kingdom has been the mainstay of our settler intake for many years, but its relative importance has declined in recent decades. Non-British European migration formed an important part of our post-war intake and, in the past few years, migration from Asia has reached significant levels - particularly through our resettlement of Indo-Chinese refugees. In planning our future immigration, it is important to look beyond short term direct economic consequences. Australia has looked to its resources for progress, but Japan, Korea, Taiwan and Singapore have achieved dramatic economic progress without resources, based on the will and dynamism of their societies. Immigration can contribute greatly to the development of a dynamic, outward looking Australian society able to make the most of our great resource potential.

Jan 1, 1982

There are three major human resource management activities which, depending on how well they are done, impact on the performance of people and therefore the bottom line. These are: ò recruitment; ò training and development; and ò performance appraisal. Most sizeable organisations would say they are involved in all three, but there are many more that would admit that their human resource management practices are limited to recruitment. If we concentrate on the organisations that currently undertake all three, we have to ask, `Are they using different systems/benchmarks for each activity, or is there congruence between the activities?'. Our experience is that most organisations use different systems/benchmarks. The end result is: ò one set of criteria to recruit staff; ò another to identify their training needs; ò and yet another set of criteria to measure their staff's Performance.

Jan 1, 1995

New and more cost-effective methods of haulage and hoisting will be needed to develop the underground mines of the future. A review of the development of technology since the 1950s shows that once mechanised equipment became available it took 25 years for appropriate mining methods to be developed and the equipment made reliable, then a further 25 years to reach todayÆs level of automation and reliability. Suggestions are made about possible areas for ongoing research with the observation that there is little research worldwide into disruptive technologies. A call is made for better organisation and presentation of the opportunities and potential benefits of new underground mining technologies.

Jan 1, 2005

The word "mine" means different things to different people. To a professional in the mining industry, it may mean trucks and shovels, overburden dumps, headframes, mill buildings, and the other conventional nuts and bolts that constitute an operating mine. To an environmental- ist it may mean bulldozed trees and tailings dams. To a mining engineer who has spent a significant proportion of his career in mine and prospect evaluation, it can mean a hole in the ground with a liar at the top. The liar in this case is frequently not so through design but through ignorance. The purpose of this paper is to contribute in a small way to en- lightening that ignorance. In doing so, it will foster more effective deployment of the pool of risk capital available to the industry.

Jan 1, 1982

By Carter D

The Chairman of this afternoon's session is Dick Carter. This afternoon is the culmination of this conference. We've looked in the first session at regulation; in the second session at valuation techniques and this session we look at valuation in practice. Dick's involvement in the mineral industry has been wide ranging and distinguished. Dick has worked with BHP since 1960, when he joined BHP Steel as a commercial trainee. Dick holds a B.Comm. from the Newcastle University College of the University of New South Wales and was educated at the Australian Administrative Staff College and Harvard Business School Advanced Management Programme. During the past decade, he has headed the minerals group's Aluminium Divison, Resource Planning and Development, Non-Ferrous Metals and Business Development Organisations. Dick currently serves as Executive Director of BHP Gold Mines Limited and Managing Director of Ok Tedi Mining Limited. His experience covers Australian Manganese Company, Mineral Deposits Limited, Northern Rivers Rutile, Tasmanian Electrometallurgical Company Limited, Mount Newman Joint Venture, Worsley Aluminium and Carnilya Hill Joint Venture Operating Committee. His industry associations include the Executive Board of the Gold Producers Association, the Federal Executive of the Australian Goldmining Industry Council as well as the World Gold Council. Ladies and gentlemen, Dick Carter.

Jan 1, 1989

Despite improving technology, better training and the use of modern monitoring and communication systems there is a disproportionate rate of diameter occurrences in the mining industry. The use of appropriate plans and a practical approach and managing risk can reduce the number of occurrences and ensure better control of emerging situations when they do Occur.

Jan 1, 1998

The limitations of the conventional practices, and their effects, in prospecting for and in the evaluation of alluvial gold deposits are briefly reviewed. Geophysical prospecting methods have demonstrated their complementary role in the delineation of deposits by reducing the number of boreholes which are primarily of a 'probing' type. Larger diameter boreholes, although more expensive on a linear basis, are much cheaper on a volume recovered basis. The need to have sufficient volume as well as number of samples is stressed. Classical statistical methods are not appropriate for such deposits as there is sufficient structure, or spatial correlation, to require the application of geostatistics. Quite reliable semi-variograms, but not in all cases, of the spherical scheme have been obtained. Subsequent kriging has, to date, been confined to unworked deposits: retrospective estimates to compare to production have not therefore been produced. However, the technique shows promise but indicates a considerably greater borehole density (of the conventional diameter) may be necessary to produce confident estimates. Used in conjunction with larger diameter boreholes, a lesser borehole density may be sufficient, through radical reductions of the sampling error.

Jan 1, 1977

The mining industry in common with the rest of Australian industry is in the critical situation of facing a rapidly diminishing insurance market. Huge industrial complexes and massive mining risks with limits of liability of millions upon millions of dollars are becoming increasingly difficult to insure. Insurance underwriters are still reeling from the financial shocks of cyclones, floods and fires in Australia over the past couple of years. Risk Management which calls for manage- ment involvement in the control of losses offers a serious challenge to miners, industrialists and insurance underwriters alike. Without it the insurance market could disappear altogether.

Jan 1, 1975

Exploration of a coal deposit provides the data on which a range of mine plans can be developed during project feasibility. The stages of exploration use methods and procedures which initially outline the deposit with more detailed data gathering and analysis of the specific site complexities. The in situ coal resource and reserves are calculated. The mine plan is a function of the mining method chosen and can have significant impact on the recoverable reserves. Other factors which can impact on the recovery of the reserves and the ability to maintain planned production levels are those which were either undetected during exploration or were misinterpreted. Exploration programs should be detailed enough to minimise to an acceptable standard the recognised and potential risks. Past programs which explored to achieve a minimum exploration density required to satisfy measured reserve status have generally proven to be inadequate, placing reserves and production at risk.

Jan 1, 1997