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By McQuade CV, Riley SJ

Acid mine drainage is an unavoidable consequence of some coal mining operations. Typically runoff pH is below 3.5 and at these pH levels heavy metals are mobilised. Leachate from coal reject dumps may require collection and treatment to raise the pH and precipitate the metals before being discharged.A bi-product of coal mining operations at Clarence Colliery is coarse washery reject. At present the coarse reject is deposited above ground and rehabilitated. Adjacent to Clarence Colliery is the Kable's Transport Pty Ltd sand mining operation. It has been proposed that co-disposal of the rejects from both operations may produce a product whose leachate has near neutral pH.

Jan 1, 1998

For various reasons, the maintenance of shaft structures is becoming an increasingly important factor in the operation of underground mines. Deterioration mechanisms related to operation of the shaft are identified as corrosion, mechanical damage, fatigue damage and wear. Deterioration mechanisms related to rock movements are identified as vertical strain, ride vertical closure and squeezing. Analytical procedures for assessing this deterioration are discussed, and it is shown how acceptance criteria are developed and implemented. In order to track the deterioration of shaft structures, shaft inspections are undertaken, but the information is often not well documented. Formalised procedures for capturing and recording information, and then processing the information are presented. Finally, two case studies are briefly described to illustrate how these procedures have been implemented in practice, and what benefit has accrued to the mines concerned.

Jan 1, 2005

Modern off-highway trucks have evolved over 30 years from small 20 ton units to vehic- les with capacities of up to 170 tons. Diesel engines are used by all manufacturers while transmissions are either mechanical or electri- cal. Development over the years has kept pace with component availability from engine, trans- mission and tyre manufacturers.Computer simula- tion studies are recognised for purposes of vehicle evaluation and costing under various op- erating conditions. Several manufacturers are currently manufacturing or evaluating vehicles with capacities of up to 260 tons. This paper describes the essential facts associated with the operation of off-highway trucks of the rear dump type in the mining industry.

Jan 1, 1973

By M Eichorn

Running a successful reagent plant trial is not an easy task, especially when trying to achieve an incremental improvement in a highly variable process, such as flotation. Cytec aims to achieve one per cent recovery improvement with 90 per cent statistical confidence. Most concentrators experience large fluctuations in recovery and so the æmagicalÆ one per cent is difficult to detect. With the aid of statistical software, including REFDISTR (proprietary) and ECHIPR, Cytec have developed a unique approach to differentiate between daily operational variation and actual process improvement. This paper describes how Cytec runs a plant trial based on extensive laboratory investigation and detailed analysis of historical plant data using statistical techniques.

Jan 1, 2000

By Bailey DJ

Loader cut and fill stoping was first used at New Broken Hill Consolidated Limited mine in 1966. The equipment used included single boom pneumatic jumbos for drilling up- holes, diesel loaders for ore removal and diesel utility vehicles for rockbolting and servicing. Since 1966, there have been many modifi- cations and changes both in the equipment and stoping method. Twin boom pneumatic or hy- draulic drilling jumbos have replaced single boom pneumatic jumbos, electric loaders have replaced diesel loaders, diesel forklifts have replaced utility vehicles and "'flatbacking" has superseded uphole stoping. Concurrent with this has been the introduction of cable dowels in stope backs which has enabled loader cut and fill stoping to be used more extensiv- ely than in the past. There are now six loader cut and fill stopes at both mines and this paper traces the evolution of this method outlining the reasons for changes in technique and equipment.

Jan 1, 1982

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

In those days no one worried - there were plenty of other things to do. But in'these days it is different. Everyone worries- and. because there is so much worry, emotion has entered the picture. And, worse than that, capital is being made in political circles. People who were quite unaware, five years ago, that any problem existed, have now become experts on the subject, and shout to high heaven that something should be done - and yet they go on using the leaded high octane petrol they deplore so much. And even scientists, who should know better, adduce only such evidence as fits the argument in hand. And the Press is not without blame - some of its reportings is open to serious question, whatever may be the excellence of its motives. The point is made that one should know what one is talking about. And make sure that the evidence quoted is fact - and make sure too, that all the evidence is used, not only that which suita the argument.

Jan 1, 1971

By Wilson O. A, White R. W G

The Mount Morgan mine occupies a unique place in the mining history of Australia and although not as glamorous during the second phase of its existence, it made a significant contribution to the technical and financial history of the nation throughout its life. The stories of the intrigue surrounding its discovery and early operation, the enormous return received by its original investors in its first five years as a public company, its influence on the local, national and international scene to its final closure have been documented in many publications, the most recent and authoritative being by John Kerr (1982). Institute publications as far back as 1911 have documented details of the mining, metallurgical and engineering practices of the two companies which worked the 100 or so acres which were alleged to be `the richest single gold mine in the world'. Within the Institute records appear the names of Presidents, Institute Medal recipients and others connected with Mount Morgan who have played an important part in the Institute history.

Jan 1, 1993

By Goldie R

The use of options theory in business has become well established in recent years and is currently one of the most exciting areas of current finance research. The theory can be used to value levered firms, and streams of contingent payments. This technique also has very practical applications in the areas of capital investment analysis and the valuation of equities in the natural resource industry. The use of options theory has been well accepted and used for many years in the trading of commodity options and futures contracts, in banking and insurance and in other industries. It also can be used to value such diverse contingent claims problems as the income tax liabilities of the firm and share underwriting agreements.Its application to the more complex options, such as those present in the resource industry, is only now becoming known. This lag is, at least partially, due to the difficult mathematics involved in solving complex options problems. Another factor is the almost overwhelming abundance of uncertainties, such as grade, tons and other natural risks, which must be considered in the evaluation mining projects.

Jan 1, 1990

Weinberg, born and educated in Germany, worked in'the American West for 10 years as a mining engineer and metallurgist. He was the first head of the Queensland Smelting Co. and from 1889 through 1915 was a prominent mining figure in Queensland. He was a competent manager at Aldershot, Dapto, and Chillagoe, but always lacked huge ore deposits for his smelters.

Jan 1, 1985

By Richards AG

The stimulus of major capital expenditure in establishing open cut coal mining operations in the Hunter Valley led Coal & Allied Industries to look to a computer based information system as a tool to assist mine management in day to day operating decisions, as well as to provide a base of comparative data to help in long term equipment procurement decisions. The mine information system was conceived as an integrated set of three subsystems; costing, production recording, and maintenance. The maintenance management features of the system are closely keyed to a policy of preventive maintenance and maintenance costing based on user specified parameters. Central to this policy is the maintenance work order, which may be created and updated directly via interactive procedures at visual display terminals. The, system was designed for on-line processing in a multi-mine shared operating environment. Each mine controls its own data capture, and most other processing functions directly from terminals. The system is currently operational on the Combined Group Services Pty Ltd FACOM M150 computer, located in Newcastle, NSW.

Jan 1, 1983

By B Ascott, J Kennedy, A White

At mines with low tonnes per vertical metre, like the Jundee Mine in Western Australia, operated by Newmont Asia Pacific, high development rates across multiple mining areas are critical to achieving the delivery outlined, or promised, in the annual business plan. The challenge is to deliver the short-term requirements while keeping in balance with the long-term strategic direction. Newmont Jundee has developed a system called æMine Planning by QuartersÆ that integrates the planning process with the business process in one end-to-end continuum. Short-, medium- and long-term schedules are reviewed and updated by applying four integrated subprocesses, which capture new information as it becomes available. The four subprocesses are: resource development planning û evaluating mineral resource,reserve development planning û preliminary design for new reserves,mine operating planning û final mine design for reserves, andmine production planning û detailed plans for stoping a proved reserve. Commercial mine planning software is used in these subprocesses to facilitate the flow of information into a central storage æhubÆ for uploading into the rolling business plan. A regular and consistent quarterly review helps to identify and qualify areas of business risk at an early stage, allowing time to plan for contingency and minimise the impact of the risk.

Jan 1, 2008

The implementation of the Mining Further Amendment) Act, 1970, and later the Coal Mining Act, 1973, placed a requirement on the Department of Mines to accept an initiative in relation to coal exploration and coal mine development which does not apply in the case of other minerals. It is necessary to consider the exploration of the total coal resources of the State when considering exploration rather than one individual basin or deposit. If the level of knowledge of the coal resources in these basins is considered in relation to their potential for development it is possible to allocate broad scale priorities to their assessment. Due to the enormity of the task which involves a conservative estimate of in excess of 400 000 m of drilling to reach a broad reconnaissance level of understanding the involvement of industry with the Department in the exploration programme is necessary. The development of the coal deposits by mining operations must give consideration to a number of constraints apart from the simple availability of the resources. Principal among these are aspects

Jan 1, 1976

Before any accident prevention and total safety programme can succeed, a safety concientiousness or attitude needs to be implanted in the employees' minds. Psycholog- ical and physiological conditions play a vital role in accident causation and prevention. Both need attention in a good safety programme, but working place conditions and environment are more easily corrected. However, the challenge is to change attitudes in the minds of men - psychological factors in accidents. To do this does not require a Safety Officer, but does require a Safety Adviser. At Blackwater mine a Safety Adviser is available to all sections of the organisation to guide and assist, to provide data and material to use at meetings, to help in accident investi- gations and to help organise training. To eventually achieve total commitment requires every member of the management team to be a salesman towards all around selling an attitude to safe working, a way of life. At Blackwater mine the workforce is young overall with most employees being under 40 years old. Psychologically this is a quite different problem to a balanced ages working group. A great deal of effort is needed to communicate with the younger, articulate, better educated employee who is also generally a skilled operator in the capital intensive

Jan 1, 1975

This paper outlines the thermodynamic and mass balance principles which affect the distribution of cobalt between matte and slag during the pyrometallurgical treatment of nickel-copper sulphides and considers the implications with regard to maximising the recovery of cobalt from the smelting and converting circuit.

Jan 1, 1994

Australia's gold mining industry has seen a resurgence in the past seven years - a resurgence the likes of which has been seen in very few, if any of this nation's other mineral industries. Industry experts are predicting that Australia could become one of the world's largest gold producers as the future of the South African gold industry looks increasingly tenuous under the present political crisis in that country. Therefore, it is utterly ludicrous for the Federal Government to introduce a tax which will see the Australian gold industry "wither on the vine."The Queensland State Government is utterly opposed to a tax on gold. Anyone in their right mind, who has seen the statistics could only agree with our stance. In 1984/85, activity in the gold mining industry is estimated to have accounted for over $750 million in national income, over$1,200 million in national output, and tax revenue of at least $115 million as well as providing more than 16,000 jobs. Chartered accountants Coopers and Lybrand's survey on the gold industry last year showed an increase in exploration expenditure by gold producers and explorers by up to 36% in 1986 from 1985 levels. That level is expected to be maintained in real terms for most of the remainder of the decade under the present tax arrangements. This is in contrast with the mining sector as a whole, where a recent Australian Mining Industry Council survey forecasted a 14% FALL in production.

Jan 1, 1986

A simple and rapid method for delennining gold and silver in carbon samples is described. The method involves dissolution of carbon ash in a strong oxidising medium of aqua regia and hydrofluoric acid. Gold and silver are determined in the resultant solution using atomic absorption speetrometry (AAS). The method is efficient and reproducible. Gold results are comparable to the standard fire assay results, with agreement of results within ± 5 per cent. The co-efficients of variation for gold and silver are 0.37 and 0.39 per cent respectively for six replicate analyses. The analysis of gold and silver in a batch of ten carbon samples can be completed in approximately four hours.

Jan 1, 1992

By K Schiefelbein, P OÆGrady, R Balusu, T Ren, T Harvey

"An extensive research program has been undertaken over recent years to reduce the risk of fires and explosions in underground coal mines. The research projects have integrated extensive field studies and computational fluid dynamics (CFD) models of goaf gas flow behaviour to develop optimum proactive strategies to prevent and control spontaneous combustion and fires ingoaf areas. The research has developed a fundamental understanding of the air and gas flowbehaviour in goaf areas and provided a detailed understanding of the eff ects of various geological,ventilation, operational and inertisation design parameters on goaf gas distribution. The researchinvestigations have also provided a better understanding of the flow behaviour of gases from the heating in the goaf areas and the effect of various gas and spontaneous combustion controltechnologies and strategies. Field studies conducted at a number of underground coal mines have shown that the proactive strategies were successful in reducing oxygen ingress into the goaf areas and in reducing the risk of fires and explosions in the underground coal mines. The results of various research investigations and guidelines for reducing the risk of fires and explosions in underground coal mines are presented in this paper."

Jun 1, 2012

The Rock Mass Rating (RMR) and Rock Mass Strength (RMS) classification systems for jointed rock masses are briefly reviewed, with particular reference to their use in slope stability studies. A correlation is provided between the results obtained from the two classifications and an equation is presented tentatively defining the RMR value for long-term stable slope angles. The validity of the equation is discussed in general terms in the context of slope stability problems commonly encountered in Western Australian open pit gold mines.

Jan 1, 1992

By R Sharpe, M D. Hannington, K Perrin, K Simpson, S Petersen, H Gibson, N Augustin, K Lackschewitz, T Monecke

Semi-massive to massive sulfides were drilled in a shallow-water (630 m) hydrothermal system in an island arc volcanic setting at the Palinuro volcanic complex in the Tyrrhenian Sea,Italy. Overall 12.7 m of sulfide minerlisation were drilled in a sediment-filled depression in a water depth of 630 - 650 m using the lander-type Rockdrill 1 drill rig of the British Geological Survey. The longest drill core recovered consists of 4.9 m of continues semi-massive to massive sulfides + sulfates with abundant late native sulfur overprint. Metal enrichment at the top of the deposit is evident in some cores with polymetallic (Zn, Pb, Sb, As, Ag) sulfides overlying more massive and dense pyritic ore. The massive sulfide mineralisation at the Palinuro volcanic complex contains a number of unusual minerals, including enargitefamatinite, tennantite-tetrahedrite, stibnite, bismuthinite and Ag-sulfosalts, that are not commonly encountered in mid-ocean ridge massive sulfides. In analogy to epithermal deposits forming on land, the occurrence of these minerals and the abundance of native sulfur suggest an intermediate to high sulfidation state for the hydrothermal fluids during deposition, implying that the mineralising fluids were acidic and oxidised rather than near-neutral and reduced as those forming typical base metal-rich massive sulfides along mid-ocean ridges. Oxidised conditions during sulfide deposition are likely related to the presence of magmatic volatiles in the mineralising fluids that were derived from a degassing magma chamber below Palinuro volcanic complex. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008