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This session comprises six papers: One paper is specifically on advances in drilling techniques, a paper presents a classification for water inrush rich with corresponding guidelines for protection, two papers are concerned with mining impacts in integrated catchment management - one from the quality viewpoint and the other from the quality viewpoint, and the final two papers are case studies of mine dewatering - one for an underground mine threatened by a karst limestone aquifer and the other of an open-cut mine threatened by interbedded sand aquifers. The paper entitled, Practical mine dewatering by means of surface drilled wells by Sides is innovative in presenting the case for wells as cost effective and appropriate for a number of purposes including exploration, re-opening old mines, dewatering, grout emplacement and monitoring.

Jan 1, 1988

A useful sampling device can be constructed using three movable flaps. One is moved between its two extreme positions as material is flowing past it; the other two are only moved while no material is flowing past them. Material commences to flow into a sample container as the primary flap is moved from right to left, continues to flow into the sample container as the primary flap is moved from left to right, and the flow is terminated as the primary flap is next moved from right to left. As for several other sampling devices, an argument that there is no delimitation error can be made on the basis that the sampler conceptually divides the stream up into discrete portions and takes a set of equally-spaced portions as a sample.

Jan 1, 2008

By P Vasconcelos, M-F Zhou, X-F Zhao

The eastern part of the Yangtze craton (eastern China ) is marked by a number of medium to small size porphyry Cu-(Au-Mo) deposits. A detailed geochronological study and existing data suggest that these deposits were emplaced in the 144 - 136 Ma interval. They are spatially and temporally related to voluminous mafic and alkaline magmatic rocks ranging in composition from gabbros, syenites, A-type granites and their volcanic counterparts. This indicates that the porphyry Cu-(Au-Mo) deposits in the eastern Yangtze craton were generated in an intra-craton extensional tectonic setting, which is distinctly different from the compressive environment of oceanic or continental arcs of the Pacific Rim where numerous giant porphyry Cu deposits were formed. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By A Galley, M Plouffe, T Hynes

Canadian mining research has recently been reinvigorated through a pan-Canadian research strategy driven by the industry, the research community and government departments. These organisations have come together to form the Canada Mining Innovation Council, whose role is to focus and increase mining research in the country. One of the major themes of the organisation is environment; including major research initiatives on energy, tailings and environmental stewardship. Other major initiatives on exploration, mineral extraction and mineral processing will also consider environmental benefits in the research projects they undertake. All the initiatives have their priorities determined principally by the mining and exploration companies, whose first obligation is to determine the long-term research priorities of the industry as a whole, rather than for their individual companies. Only after industry consensus on priorities does the research community become engaged in the implementation of specific projects to address those identified priorities. A goal of the program is to effectively create a virtual mining research laboratory, by engaging all the major research centres in the country. Membership to date includes most of the major mining companies operating in Canada and almost all of the mining-related universities. Other members include federal, provincial and territorial governments, consulting and service companies and manufacturers.CITATION:Hynes, T, Plouffe, M and Galley, A, 2012. A new approach to mining research in Canada, in Proceedings Life-of-Mine 2012 , pp 333-338 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By P Krauss, S Harpalani

Methane emitted from underground coal mines, along with ventilation air and known as ventilation air methane (VAM), constitutes the largest component of coal mine methane (CMM) emissions. Atmospheric methane, on the other hand, is a potent greenhouse gas with a significant adverse impact on the atmosphere. This has led to the development of various technological alternatives for its use as an energy fuel. Techniques involving oxidation of VAM, usually consisting of very low concentrations of methane, have been validated in the past. Prominent among these technologies are the thermal and catalytic flow reversal reactors, ancillary fuel technologies, lean fuel gas turbines, and concentrators and gasifiers. However, the efficiency of any VAM utilisation technique depends on the amount and concentration of methane in the ventilation exhaust air. Therefore, quantification of VAM emission from a coal mine is the first step towards identifying the most suitable technology for its utilisation for energy production. This paper presents an evaluation of the efficacy of VAM as an energy source. It provides details of a case study aimed at developing a technique to accurately quantify VAM emission from a coal mine. It further discusses the various VAM utilisation techniques available, and presents an economic evaluation of the alternatives. Based on the findings of the study, the most feasible method for VAM utilisation is identified for the mine. The paper summarises the procedure for quantifying VAM emissions and selecting the most suitable utilisation technique.

Jan 1, 2005

Most mining projects will involve some level of financial markets price risk. This is because commodities are generally traded in $US. The project will also incur costs in $A and if based in Australia will seek to generate a return in Australian dollars. Therefore the project faces commodity, foreign exchange and interest rates risk. As a business you may wish to maintain these risks within your business. However if the project requires financing to be provided then the financiers will want to ensure that there is a level of certainty attached to the cash flows to support the debt repayments. This is achieved by hedging the financial market risks. Traditionally the hedging process has been based on underlying assumptions within project models, which incorporate views on the direction of the underlying price risk. These views can be formed in an ad hoc manner. Gathering information from a variety of sources including economic forecasting and modelling, technical analysis, seeking market expert views. However, given the historical accuracy of such forecasts locking into long-term fixed hedging arrangements can create an inflexible environment that can restrict the opportunity to benefit from the underlying volatility of financial markets.

Jan 1, 2003

The concept of "profit" is implicit in the definition of an ore reserve. It is suggested that the flexible concept "economic" is more appropriate. This allows different economic considerations to be taken to account when determining what is ore at the feasibility study stage; during actual mining production; before mine closure; and from the viewpoint of the national economy. Economic factors which are highly variable, and largely beyond a mining enterprise's control, affect the economic exploitation of a mineral resource. Major economic factors include: metal prices; operating costs; the cost of original and replacement capital equipment; the cost of capital; taxation and royalties; inflation; exchange rates and the state of the world economy. The paper suggests why a careful quantification of the average value, trend, and variation from the trend of major economic factors should be made and how this will lead to a better definition of ore reserves. The paper also discusses the necessity of reappraising economic factors during the life of a mine in order to maximise the economic surplus and to minimise the wastage of natural, economic and human resources employed in mining.

Jan 1, 1979

THE following notes simply sum up the writer's experience, which extended over a very busy period of some three years, dealing with wolfram ores and concentrates. The three methods for the estimation of tungsten that are discussed below are well known, but these results of their trials and comparison under technical conditions may be interesting. Method I. The routine procedure for the assay of rich wolfram ores or concentrates was as follows: Take 1 gram of finely-ground sample; digest with HCl and HNOs for about 2 hours, evaporating down to near dryness. To the remaining 5 cc., say, of liquid, add water, warm or boil for 1 to 1.5 hour, filter through a small filter paper, and wash the beaker and the insoluble matter with hot dilute HCl. It is best to keep the bulk of the insoluble matter (WOs, Si02, etc.) in the beaker at this stage. Then plaee a weighed porcelain dish under the filter funnel and wash the beaker and the filter paper with successive small quantities of strong NHOH, finally bringing all the insoluble matter on to the filter paper, and collecting the ammoniacal filtrates in the porcelain dish (S). Then place the filter paper with the insoluble matter in a porcelain crucible, dry and burn off the paper, cool, and brush the contents of the crucible on to an agate mortar, grind it to flour, and brush this back to the original beaker without loss. In the absence of draughts this can be done safely. Re-treat this residue with' acid and ammonia as above, running the second ammoniacal filtrate into the previous porcelain dish, which in the meantime has been heating on a water-bath.Finally evaporate to dryness on the water-bath the combined ammoniaeal filtrate, and then heat gradually to a red heat over a Bunsen burner, cool, and weigh. Then the contents of the porcelain dish give the WOs (tungstie aeid) direcvly (5).The final filter paper and insoluble matter may be ignited in a porcelain crucible, thus giving the "insoluble matter." If the ore...

Jan 1, 1922

The Pacific Rim and its environment involves a vast array of natural phenomena, and a vast array of situations which show the impact of man. Almost half the world's population of over five billion live in nations" which border the Pacific, but the concentration is focussed in the North. Great experiments are occurring in this region, the industrialization and energy development in- Japan and China, the growth of Indonesia, (now 168 million - soon 368 million; Brown and Jacobson, 1986), the enormous developments of agriculture and the metals resource base in Australia and China. At the same time, the Pacific Rim does not project images of hopelessness, the mood is upbeat. Over the past decade, incomes have increased substantially in most of the major countries of Pacific Rim (e.g. over the period 1980-86, + 58% in China, + 21% in Japan, + 34% in South Korea; Brown and Jacobson, 1986). In September, 1986, at the general assembly of the International Council of Scientific Unions (ICSU) in Bern, Switzerland, representatives of over 50 nations approved a new initiative, "The International Geosphere Biosphere Programme: A Study of Global Change". The focus of this new program is "To describe and understand the interactive physical , chemical , and biological processes that regulate the total Earth system, the unique environment that it provides for life, the changes that are occurring in this system, and the manner in which they are influenced by man. The IGBP will be a tightly-defined programme of research, directed at providing fundamental knowledge that will serve as a basis for assessing likely future changes on the Earth in the next 100 years" (ICSU, 1986). For the earth scientist, and all resource scientists, there is an emerging agenda; new priorities are appearing, new questions are being asked. The recent report of the World Resources Institute (1986) focusses on this emerging agenda. Topics which are at centre stage in this report include the following: The environment and human health Tropical deforestation The atmosphere as a shared resource and climates Soil-degradation Rural-urban migrations Food and agriculture The diversity of species-ecosystems Freshwater as a finite resource Coastal areas and resources

Jan 1, 1987

Over the past 12 years screening of materials has undergone a dramatic change in both the types and materials used in screen mats and the quality requirements of the finished product. With the main thrust now on quality and a cleaner product a different approach was needed in the operation of sizing screens. New screen mats with many different aperture configurations have been developed using rubber and plastics.to replace the traditional screen mat of woven wire or punched plate.

Jan 1, 1984

The Plant Control and Data Logging System for the Loy Yang Open Cut (LYOC) is part of a control and communications network designed to provide a high level of surveillance of open cut plant and facilitate the efficient co- ordination of operations and plant maintenance. The computer system selected utilises a central dual mini-computer and multiple microcomputer data transmission network ,linked to the plant controllers using distributed, microcomputer based remote data collectors or outstations. Several aspects of the computer system are outlined.

Jan 1, 1982

By Robinson J

A stibnite flotation concentrate from Costerfield in Victoria was found to contain 63.3 g/t An while its sizing distribution indicated that 81.6 per cent of the material was less than 38 ¦m. A 24 hour cyanidation test by a standard bottle roll method recovered 15 per cent of this gold. Pressure cyanidation under conditions of ambient temperature, 40 per cent pulp density, an oxygen pressure of 1000 - 2000 kPa and an initial NaCN concentration of 15 kg/t, resulted in a recovery of 65 pe cent of the gold after only two hours of leaching. Aqueous pressure preoxidation of the concentrate followed by the standard bottle roll cyanidation realised gold recoveries as high as 96 per cent. Conditions of 220¦C, an oxygen pressure of 1000 - 2000 kPa, 16.7

Jan 1, 1991

By Soldenhoff K, Levins D, Collier D, Day A, Secomb R, Brown S, Tapsell G, Bellingham A, Quan C

Bench and pilot plant studies were carried out at ANSTO to develop a process for rare earth recovery from the Mt Weld deposit near Laverton, Western Australia. This paper describes the development of the flowsheet, which is similar to conventional monazite processing, but with the introduction of several innovative steps to account for the complex rare earth mineralisation and the presence of specific gangue minerals. A unique feature of the flowsheet is the recovery of cerium by solvent extraction from a sulphate leach liquor. The process was tested continuously by the operation of a pilot plant at ANSTO's Lucas Heights Research Laboratories, Sydney in the first half of 1992. The plant, designed to treat 100 kg per day of beneficiated ore, confirmed the viability of the process, with rare earth products from the operation satisfying stringent buyer specifications.

Jan 1, 1993

The scale and seriousness of AustraliaÆs social and environmental problems are no longer in doubt. We are consuming the opportunities of future Australian generations by our lifestyle choices. And at the global level, human activities are altering the very systems on which our species depends. Doing nothing about such problems as climate change is not an option. It is possible to move to a sustainable future but it will require fundamental changes to our values and national social institutions. We must recognise that we share a common future with the entire human family and the other species with which we share the planet. It is not just our humanitarian duty to improve the lot of the poorest people of the world. It is also enlightened self-interest because a world of increasing inequality will be a world of increasingly destructive tension.

Jan 1, 2004

Multiple regression analysis applied to ventilation records of stopes on the Witwatersrand showed that it was possible to estimate the temperature increase per 100 ft for a new stope with a standard deviation of 0' 5°F. The analysis also threw light on the relative effect on this estimate of five different factors.Application of the analysis of variance technique to a factorialexperiment on the production of dust during rock drilling showed that the effects of air and water pressure were quite small but also showed that the between-machine variation was unexpectedly large.Analysis of variance also proved a valuable means for assessing the bias and random error variation of aneroid barometers used in pressure surveys.INTRODUCTIONThree examples are discussed to illustrate the use of the techniques of "analysis of variance" and "multiple regression" in research on the ventilation of gold mines. Although the techniques are basically similar their application to each example has a slightly different emphasis and the examples were chosen for this reason. The variation ofemphasis is as follows.1. Temperature increases in stapes. This work was undertaken as a preliminary to possible extensive controlled experimentation (Lambrechts, 1959). Data collected in routine work by the mine ventilation personnel were used for analysis and no specific experiments were carried out. The main object was to see whether such data could provide any strong pointers to factors which might be worthy ofmore careful study and to factors which could initially be ignored. Of course, there was hope that the study might provide an empirical formula for rough forecasts.

Jan 1, 1962

By B Leyland

The media in Australia is currently rife with articles and pronouncements on global warming as the most significant crisis of our time, which may æthreaten the future of civilisation as we know itÆ. This has been recently reinforced by release of Al GoreÆs film æAn Inconvenient TruthÆ, and one would be led to believe that the science of global warming is settled. And yet there is a strong body of literature disputing this apparent consensus which suggests that care should be exercised in introducing radical policies to solve a crisis which may not be real. Such policies would have a major impact on those in professions such as engineering (project approvals and design to minimise greenhouse gas emissions), accounting (carbon tax issues) and the law (corporate disputes on greenhouse gas issues are already in train in the USA). This paper addresses the hysteria apparent in the climate change debate by presenting factual evidence relating to climate change and the current phase of mild global warming. Some of the more extreme statements on future impacts are repudiated with published data, and alternatives to the purported role of fossil fuels in temperature change are offered. The potential impact of political decisions on professional activity is discussed, as are the implications of a possible future reversal of the scientific consensus, as has occurred in the past. The paper concludes with a call for the professions to exercise their Learned Society role to ensure that a rational and public debate is held on the broad issue of climate change.

Jan 1, 2007

Away from past controversial presentations, a matter of fact, intuitive and simplified approach to the Theory of Sampling (TOS) sampling variance prediction formula is offered which gives an insight on the type of model required for the liberation factor, the practical limitations of such model and methodological principles for its calibration. This paper intends to see what happens in TOS when trying to go from the very simple towards the full level of real life complexity, and actually tries to answer the question: Is there such a thing as a æsimpleÆ TOS?

Jan 1, 2005

By Wilson T, Stone M, Mattiazzo R

The regulation of environmental management in the minerals and petroleum industries has been undergoing considerable change over the past decade. In recent years, there has been a distinct trend towards smaller government and increased environmental awareness. Current regulatory systems have generally neither responded to these trends nor effectively dealt with the demands placed on them. There is a need to develop a more effective means of providing assurance to Government and the community that its environmental objectives are being met. These means must also enable industry to have an effective environmental management process.

Jan 1, 1993

Taxation is a major factor in evaluating mining project developments. The availability or otherwise of effective tax relief for project expenditures can have a crucial bearing on the decision to proceed with a project. The special position of the mining industry is recognised within the Income Tax Assessment Act (the "Tax Act") by special legislation, namely Divisions 10, 1OAAA and 10AA. The legislation both extends the scope of items which are eligible for deduction and affects the timing of deductions. Generally, the legislation separates expenditure into 3 categories: 1. Expenditure on exploration 2. Capital expenditure on the development and the running of the mine; and 3. Facilities used in the transport of minerals. Companies evaluating a project should carefully analyse their proposed expenditures, allocating them between these categories so as to identify potentially non-deductible expenditures and to determine the period over which tax relief will be Obtained.

Jan 1, 1983

The kinetics of the hydrogen reduction of iron oxides in granular calcined bauxite were studied at 550-1,050°C in a shallow bed reactor. The iron oxides behaved as a dispersion of particulate iron oxide in a porous alumina matrix in which the iron oxide particles were reduced independently. The observed rates of reaction were found to be virtually independent of the bauxite grain size. At 800,°C and above, the reduction was multistage, Le.1. Fe203 +2Al203 (matrix) ?2FeAl204, and2. FeAl204? Fe0 +Al203.Reaction 1 was very rapid. Reaction 2 was much slower, the latter stages being controlled, at least in part, by phYSIcal changes of the Fe0 and a-Al203 produced in the reaction. Owing to the observed nature of the material, the reaction rate controlling steps could not be determined.

Jan 1, 1972