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Scientific drilling and blasting techniques are currently being presented to the mining industry as an aid in the overall optimisation process. The degree of success in the development of these techniques over the last ten years has prompted statements that generally relate to blasting becoming a science rather than an art. Many of the techniques are currently operated or at least analysed by scientists. As such, their use has been restricted to project type activities while the more routine activities associated with day to day mining has continued to be carried out by engineering rather than scientific staff. Some of the scientific techniques will remain legitimately as a project or an occasional use facility. Generally speaking a cost/benefit analysis at a particular mine will decide the level of use. This should logically highlight a number of techniques with potential of regular mine site use. Regular mine site use implies mine site analysis and hence the gulf between the scientist and mine operator/engineer must be addressed. There are all sorts of solutions and they are not mutually exclusive. One alternative could be to increase specialisation at the mines. With "career paths" becoming more formalised the trend would seem to be away from mine site specialists unless, for instance, this specialisation was provided by term secondment from research establishments. Another alternative could be the scientists themselves applying their developmental skills to "humanise" and "package" the projects in such a manner that they can be routinely used at mines.

Jan 1, 1990

By Andrew R. L

The Kintyre uranium deposit was discovered in 1985 in the course of following up radio- metric anomalies generated in an earlier air- borne survey. The latter survey was conducted primarily to acquire aeromagnetic data for diamond exploration and the uranium discovery was made during a subsequent campaign of base- metal exploration. CRAE commitment to the Rudall area for a range of commodities over a period of 13 years made a significant contrib- ution to the discovery of Kintyre. Other con- tributing factors included CRAE's multicommod- ity approach to exploration, management support and continuity in the geological team. The Kintyre uranium deposit (Fig. 1) is located on the northern margin of the Rudall Metamorphic Complex, 60 kilometres south of Telfer and 260 kilometres north northeast of Newman, in the Paterson Province of northern Western Australia. It is 700 metres inside the northern boundary of the Rudall River National Park (15695 sq. km) and lies between the Great Sandy Desert and the Little Sandy Desert (Beard, 1969). Intense weathering since the Permian has produced a subdued landscape around the deposit. Resistant rock types still retain an older plateau surface but it is incised by more recent streams. Other Proterozoic and Permian rocks form low, sometimes rocky, areas largely covered by aeolian sand.

Jan 1, 1988

By M McCarthy

Attraction, recruitment and retention of quality mining engineers is becoming increasingly difficult for many mining companies. Part of the problem is attracting young professionals, especially given the decline in graduating engineer numbers, and the other is balancing the new engineerÆs development with business needs. The evolution of the graduate program at Olympic Dam over the last five years has resulted in substantial benefits for both the engineer and the company. The program has developed to provide structured exposure to key areas of the mine enabling new engineers to step into vacated roles as the need arises. The pool of quality engineers generated by the graduate program is a buffer against high industry turnover and helps reduce future recruitment expenditure. Olympic DamÆs program goes beyond conventional recruitment of graduate engineers. Innovations designed to improve intake include the employment of graduate engineers as well as final year students, retraining of existing personnel from other backgrounds and fast track recruitment for previous vacation students. By employing a cross-section of professionals to complement the generic university graduate, the company takes full advantage of the relevant lifestyle experience belonging to the individual, which is a substantial factor in turnover. Study assistance and a salary paid for final year students and mature age students often creates a loyalty that lasts beyond graduation. Careful selection of vacation students increases the ease of recruitment at a later stage and ensures that full advantage is taken of the relationship developed previously between the company and young professional. The evolution of recruitment at Olympic Dam has seen a decline in the turnover statistics of young mining professionals.

Jan 1, 2005

It's my privilege to welcome you here this afternoon on behalf of the Sydney Branch of the Australasian Institute of Mining and Metallurgy. This is a most important gathering. You, the delegates, represent what is probably the most influential cross-section of the mining investment community and the oil and gas investment community to meet as a group during the last decade. We are meeting today and tomorrow to review two related issues that will have far reaching implications for the effective use of capital by the natural resources sector in the 1990's. The views which will emerge over the two days will almost certainly 'influence the availability of new capital to the companies in the natural resources sector for the decade ahead. The two principal themes of Minval '89 are, first, the valuation of mining and oil and gas assets and securities, and second, disclosure and reporting requirements in the capital markets which relate specifically to natural resources companies. This conference is taking place at a time when further consolidation and rationalisation appears likely within the mining industry. Although the base metals and other sectors of the industry are enjoying profitability not seen since the early 1980's there is caution about committing to new capacity which could bring about a return to the low prices and excess supply which prevailed during much of the last ten years. These conditions have led to increased takeover activity within the mining industry overseas, and similar trends are as evident here in Australia as they are elsewhere. Recognition of value is therefore likely to become more important than ever before in preserving shareholder wealth, for creating new wealth and for preserving the financial health of the resources industry in the future. Valuation therefore is the first theme of the conference.

Jan 1, 1989

It is generally known that Charters Towers was discovered by Mosman, Clarke and Fraser in 1871. However, the time was ripe, and these three were barely in front of others. There is one account that prospectors from Ravenswood visited the area months before but decided it was too far from water, and that one of them had told Mosman and party of the find. There is another account that Joe Larkins found the discoverers before they had registered any ground - this may explain Mosman's quick departure for Ravenswood.When the news spread, the rush was rapid, and there was soon a sizeable population: probably too many, as within twelve months the infant settlement was under considerable stress. First, the presiding Gold Commissioners had adopted "unusual and arbitary" interpretations of the Regulations, and many of the miners were aggrieved; Charters, the senior Commissioner, was accused of favouring moneyed interests, and of retiring ill whenever a brawl or confrontation occured. As a result, the law of the field soon became "the survival of the strong". Second, the settlers were, divided on where the main town should be: Millchester, near the water, or Charters Towers near the mines. Third, the discovery of gold at the Millchester Deep Lead in August, 1872 was followed by highly exaggerated accoants in_' the southern papers, apparently fabricated by local business speculators. The resulting rush resulted in hundreds of unlucky prospectors having to return or seek other fields. In that period two men were killed in squabbles over ground. To make matters worse, by October 1872 a drought had set in, water cost three pence a bucket, fodder was scarce, cartage expensive, and the price of crushing ore rose to thirty shillings per ton.

Jan 1, 1986

Completion of a project requires two separate money-focused activities, namely economic evaluation of the cash flows underlying the project (before financing) and if the economics look promising, how it can be financed. Economic evaluation might be best led by a person with a technical-operating background, whereas financing might be best led by an accountant. Both should be presented in simple language with easy to understand models. Economic evaluation has a sad and bad history because it evolved from the fringes of accounting. Anyone can become a self-appointed practitioner. Some still take pride in mathematical complexity without realising that they distance themselves from the decision-makers and alienate other team members. Today there is no evaluation modelling consistency across the mining industry and this reflects poorly on our discipline. It is not tolerated amongst our peers in engineering and accounting. In 2009 æbest practiceÆ economic evaluation modelling is well defined. It is:easy to follow;tailored to its purpose;transparent;discipline, rigour and consistency;recording of all source data; and hencequick to audit. Mantra: If you cannot readily understand my model you do not have a problem, I do! The task of the economic model is to make the range of business cases underlying the decision easy to understand. Intellectual power is used to simplify the decision to its key issues and risks and to present the full range of possible business outcomes in readily understood terms. Project team members, management and the board must be able to make their decisions with æeyes wide openÆ. A steering committee should be established to develop a set of standards and practices that could be adopted for economic modelling within the industry. The industry needs to purge itself of the undisciplined economic evaluation modelling that now characterises the discipline.

Jan 1, 2009

By D Sinclair

Sustainability will become a more stringent issue in mine planning over the next 40 years. The evidence of this is apparent in State and Commonwealth government policies now emerging in respect to water, green house gases, waste and other process emissions. The mining industry has developed policies such as æEnduring ValueÆ, which go some way towards establishing a framework within which mining can continue to be an underpinning strength within the Australian economy. However, the demands of new policies are directed at extending sustainability in ways that will change the way in which projects are implemented. This paper examines the nature of new policies aimed at water, energy and emissions, considering examples of where mining practices have or may change in order to meet new objectives in resource efficiency. Important issues will, as always, be the international price competitiveness of the mineral resources being produced but, where this is now devolved around mining and processing costs, these costs may in the future be strongly correlated to the nature and cost of local energy resources compared with those in Australia, the ability to mitigate and minimise water resource use and environmental impacts deriving from emissions and the veracity of competitor nations in meeting the same standards of performance in resource efficiency usage and in emissions control. As these systems bed down internationally mining in Australia will need to concentrate, amongst other things, on finding higher grade orebodies and on better technologies to release the value of lower grade ores. For our mining industry to remain strong, greater expenditure will need to be focused on these objectives. Finally, it will be important for the industry to remain vigilant and proactive in directing government policy development to ensure that practical objectives in mining are not curtailed unnecessarily through ignorance of mining market precepts developed over the centuries of mining operations.

Jan 1, 2008

By A Scott

Long before a modern mine commences operations it has already become a wealth of information. After start up, it can generate enormous quantities of data û especially with semi-automated data acquisition by instrumented mine equipment. However, much of this data is of limited use for evaluation of (potential) performance unless it links in some way to the site business model. An underlying reason for this waste of data is that the different cultures, financial, technical, community, environmental, etc not only have many areas of interest but also have very different conceptual models by which they evaluate performance. It is too ambitious to attempt to bring all of these cultures together û in a single step. However, the success of the Mine to MillTM project has demonstrated that substantial operational value can be added by using a more integrated approach to comminution. The next logical step is to integrate measurement and then to track performance from orebody model to saleable product and waste disposal. From resource to product also represents a path from very sparse, highly variable data to much more detailed measurement and more representative sampling. However, in both cases the data collected is strongly focused on the technical requirements û not on the business model. This paper considers how to define at least some of the key decision points in terms of some case studies. Performance data from many areas might be used to derive simple models which can then be used for forecasting and optimisation of planning.

Jan 1, 2002

By J S. Moema, R Paton, J Zimba

Today, most organisations are familiar with the pressure to increase their effectiveness and efficiency, regardless of the nature of their business. Cost cutting and increased productivity are the main themes of many initiatives to ensure the profitability of operations and, ultimately, shareholder satisfaction. It is well known that the cost of comminution to liberate minerals such as gold from their respective ores is a major expense for mines. Comminution costs consist predominantly of grinding balls and electricity. However, there are no national or international standard specifications for grinding balls û on which a single mine may spend several million dollars per month. In addition, in the past mines generally did not specify the minimum requirements when purchasing grinding balls from suppliers. The result is that every supplier has its own grinding ball recipe (regarding chemistry and heat treatment), and is under no pressure to implement a quality assurance plan to ensure that a consistent product is delivered. The resulting variation in the quality of grinding balls leads to increased steel consumption rates and hence increased milling costs. A more stringent quality plan will generally not be welcomed by suppliers since this may entail further investments and/or reduce the production rate. In a sense, suppliers benefit from poor quality grinding balls as this leads to increased sales. Perhaps the main problem is a lack of understanding of the factors that influence grinding ball performance. This paper will describe the factors that influence the wear rate of grinding balls from both a microstructural perspective and a mill perspective. In addition, some insights are provided on the different grinding balls available and ways that users can verify their quality.

Jan 1, 2007

By T E. Norgate

Salinity in Australia is caused by over irrigation and land clearing for agricultural use over the last 100 years. It is now the biggest threat to the quality of land and water in the Murray Darling Basin and Western Australia. Pumping the saline waters straight into the ocean or transporting the solid residue (mainly sodium chloride) to the ocean after evaporation of the water is expected to cost the taxpayer millions of dollars every year. This paper proposes that the salinity problem of Australia, at least in part, can be converted to an asset rather than a liability if it is exploited and used to make value-added products. The more value made out of saline waters, the more saline water is processed and therefore the more salt is extracted from the land. The value-added products that can be made out of saline waters are numerous and diverse. Rough calculations show that value addition to the saline waters could potentially generate up to $A 200 million per annum business in the Murray-Darling Basin. Although it is a challenge to make cost competitive products and find markets for these products it is possible that up to $A 100 million per year may be gained from import substitution. Value addition to salinity would also reduce the threat on the environment and existing agricultural industry. Investment to add value to salinity will create business in the region, nurture the local small population communities, and increase services and long-term employment.

Jan 1, 2002

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

By S Pfaff, R Rajic

In the case when the number of independent variables is greater, a careful design for carrying out tests has to be made in order to obtain, with the smallest possible number of tests, as much as possible neutral information about the influence of independent variables on the dependent ones. Only on the basis of such design and its statistical analysis it is possible to come to right conclusions about the function of the whole system. The influence of pressure, temperature, humidity and granulation of the coal upon the resistance to pressure and the water absorption of the briquettes has been tested, with the aim to examine how each of the two dependent variables changes depending on the values assumed by any of the four independent variables and which of the mentioned independent variables significantly influences the dependent ones. The full factorial design with 16 experiments and the central composite design with 27 experiments have been applied. The influence of the independent variables upon the dependent ones has been examined by applying the analysis of variance. The influence values of individual factors and their interaction upon the dependent variables have been stated as well as coefficients of curvilinear equation.

Jan 1, 2003

By B Cooper

During the design of a new production facility for a greenfields or significant brownfields expansion many design decisions are made driven by an unquestioning objective to achieve 'lowest cash-cost' production costs. In many cases this translates to a design and operating philosophy based on largest-available, single-line equipment. Although acknowledged as an approach that is efficient from an operating cost perspective does this approach always maximise shareholder value? There is an increasing awareness in the mining industry of the value of project flexibility, robustness and value options. The design of a new production facility creates a window of opportunity which should be structured to ensure that project value options and robustness are understood and exploited. This requires the use of emerging valuation methodologies, such as Value-at-Risk and Real Options, as well as tried and trusted NPV/IRR approaches. The paper provides an overview of the basis and application of these less well known techniques in the context of metallurgical plant design. Design guidelines that demonstrate how value options and flexibility can be quantified from both a risk and value perspective are presented. Issues such as use of single versus multiple line equipment, optimum cut-off grade and improved exploitation of the inherent variability of the orebody are also examined. Finally the management issues and approaches to achieving this will be briefly discussed; for example it is common during project development to drive towards increasing certainty as rapidly as possible to facilitate 'accurate' estimation of costs. Understanding and exploiting value options requires a project culture that tolerates, and revels in, ambiguity and uncertainty û something that would make many project teams uncomfortable!

Jan 1, 2008

Although the effects of sea level changes on ore concentration processes are to some extent obvious with certain deposits, e.g. beach placer deposits, they have been largely overlooked with others such as Mississippi Valley type lead-zinc deposits. It is contended that sea level variations may have more profound effects on a wide range of deposits than has previously been appreciated. These deposits include not only placer'and residual deposits but also stratiform copper deposits, Mississippi Valley type deposits, stratiform manganese deposits and Minette type iron deposits. Sea levels in paralic basins profoundly affect the influx of 'detrital sediment, and this has to be suppressed to allow for the accumulation of thick rich deposits of coal evaporites, phosphate or metalliferous sediment. Emergence can be associated with oxidized waters, erosion, and,solution of soluble rocks. Submergence can reverse the Eh trend and can lead to preservation of ores. Both realms of surficial sedimentary environments and subsurface diagenetic environments can be affected by changes in water pressure, gas pressure (pC02), Eh, pH, and temperature as sea levels fluctuate. Even relatively small sea level changes may have profound effects. For example, there is some evidence to suggest that when the level dropped below 100 metres about 10,000 years ago, the Red Sea became isolated by the sill at Bab el Mandeb in the south, and evaporated away to leave a series of shallow lakes. The Red Sea is 1 to 2 km deep. It was at times such as this that the well-known copper-zinc mineralization developed in the Red Sea trough. Changes in sea level also affect the stability field of gas hydrates which can yield large volumes of gas leading to mass movements on the sea floor (Warnke, 1986).

Jan 1, 1987

By D E. Langberg, D R. Swinbourne

The past century has seen the development and commercialisation of many new pyrometallurgical processes based on gas injection. The driving force behind this trend in smelting and refining technology was the increased productivity and resulting increase in capital utilisation achievable. However, measurement of system variables is not easy and their effect on the rate of the reactions involved is not well characterised. One of the critical parameters is the gas-liquid interfacial area produced by gas injection. Related variables such as bubble size and velocity, and gas hold-up fractions in aqueous systems have been measured using combinations of physical (visual, audio and electrical) and chemical techniques. Models have been developed relating interfacial area to physical properties and operating variables and attempts made to extrapolate these to high temperature, liquid metal systems. The only attempts at validation of these models have used either low temperature liquid metals, such as mercury or WoodÆs Metal, or operating plant data. This paper reviews existing knowledge of the effects of system variables on total interfacial area in gas injection systems. Interfacial area is calculated from a range of published experimental aqueous and liquid metal systems and used to assess existing models. An operating region diagram was developed to assess dynamic similarity between experimental and industrial systems. It highlights areas where further research into both measurement techniques and experimental system variables is required in order to extend knowledge and guide further technical and design advances into the 21st century.

Jan 1, 2000

By M Noppe, I Glacken

There are many critical nodes along the mine value chain, from orebody to mineral product, and inter-disciplinary input is required to analyse the variability and uncertainty at each node in order to identify and mitigate areas of risk. Mining differs from many other industries in that the variability in the product is dictated largely by the inherent nature of the input material (the orebody). The true characteristics, including the variability of the orebody, are never known exactly and are instead based on estimates derived from sample data. A further difference is that bottom-line gains are largely controlled by world commodity prices, which can vary with time, rather than by local supply and demand issues. Methods for identifying, reporting and responding to this inherently variable raw material are discussed. These include analytical and reporting methods, equipment and software, risk analysis and reality checks (eg reconciliation). Sampling results, mineral resource and ore reserve estimates and economic assumptions are a function of the variability of the orebody. Risk quantification should be expressed as a level of confidence, which takes into account the scale or period over which the risk is being assessed (life-of-mine, annual or shorter production periods) and should convey the likelihood, severity and consequence of occurrence of a given event. The future generation of mining specialists needs to understand the entire mine value chain to better manage risks and maximise mine dollar-value.

Jan 1, 2002

The management of safety has undergone a number of radical changes in the past 100 years. The most important paradigm shifts occurred through the work of Heinrich, followed by the advent of the safety systems era and, more recently, the behavioural safety approaches that have become increasingly popular around the world. Each of these æapproachesÆ to safety has left an indelible mark on the way we target safety improvements, helping decide which interventions are deployed and how they will be measured. They have also resulted in a number of æmythsÆ about safety management, each of which will be discussed, analysed and challenged in this paper. This paper highlights the complex problem of æcomplacencyÆ, that has arisen out of the increased levels of regulation and consequent perceived protection that workers enjoy in the work place. It also looks at a phenomenon called æaccident migrationÆ which results from a superficial treatment of accidents with changes to rules and procedures. The most recent approach to safety is generally known as behaviour-based safety, which flowed from the human sciences and quality management era. This approach has had a dramatic impact on the way safety is managed around the world, but still falls short in a number of key aspects, most notably the area of risk awareness and risk understanding. Many workplace accidents occur simply because the risk is unidentified, underestimated, not understood or ignored. This paper proposes a new direction for safety, called competency-based safety. It is based on cognitive psychology aimed at combating the consequence of modern protection. A case study is presented detailing the deployment of this approach throughout Placer Dome.

Jan 1, 2005

Mr. P. F. THOMPSON said this matter was one of very great importance to producers of lead. His association with the matter was that he happened to be the Institute representative on the Committee of the Standards Association of Australia charged with formulating a standard for chemical lead, that is, lead used in technical chemistry for acid chambers and the like. The British standard had this test incorporated in it, but those on the committee felt that it should not be included in the specification. The main objection was that in an accelerated corrosion test one was endeavouring to do in a few seconds what in natural conditions would take years; and it was now being recognised that such tests were of little value in assessing the corrosive properties of a metal.The flash point test was carried out with boiling hot strong sulphuric acid; but no chemical manufacturer would be likely to use such in contact with lead. There were many factors such as the formation of steam, the chemical reduction of sulphuric acid, the evolution of hydrogen, the catalytic effect of the surface lead, affecting this test, other than the presence of the segregated impurities upon which this test throws the onus of the whole imperfection of the lead. Mr. Russell had shown that lead which had stood the test of time often gave a low flash point. They were endeavouring to find rapid methods of estimating minute amounts of the more important impurities, which would eliminate the labour and expense of a full analysis.Mr. H. St. J. SOMERSET thanked Mr. Thompson for his remarks. He supposed some of those present knew that the Broken Hill Associated Smelters was responsible for Mr. Russell's investigations at the University, and he could only agree with Mr. Thompson that the flash point test, which had been accepted at the present time...

Jan 1, 1930

While the potential for the discovery of new high grade resources exists, it is almost inevitable that the ore resources used to provide society's ongoing demand for primary metals will deteriorate over time as the higher grade reserves are exploited first and are progressively depleted. This deterioration in quality of metallic ore resources will bring about significant interactions with other resources such as energy and water, resulting in an increase in the amount of these resources required per unit of primary metal production. In this paper it is shown that as ores deteriorate in quality, the contributions of the mining and mineral processing stages to the life cycle-based embodied energy and water of primary metal production will increase significantly. Therefore efforts to reduce the impact of deteriorating ore resources on energy and water consumption should focus on these stages.   The results from life cycle assessments of the production of various metals by a number of different processing routes, particularly copper and to a lesser extent nickel, have been used to identify a number of opportunities and technologies for reducing the energy consumption in the mining and mineral processing stages, including: comminution, eg high pressure grinding rolls, stirred mills, ore sorting, preconcentration, advanced blasting techniques, advances in diesel technology for loading and hauling, alternative processing routes, eg heap leaching, in situ leaching, water treatment and re-use, water quality 'fit for purpose', dry processing, floating modules to reduce evaporation, and paste thickeners. All the above and existing developed flotation technologies can impact on the mineralogy of the concentrate supplied to the smelter. Removal of gangue minerals early on in processing may have further downstream process implications on fuel and water requirements. The above technologies are in various stages of development, with some more advanced than others. However, all can be expected to play their part in improving the sustainability of the Australian mining industry.

Jun 1, 2010

DIVERSITY There are plenty of examples to show that diversity has been the fundamental downfall of many organisations, particularly when you consider the international position. What about core business, the return of companies to key competence directions and market focus. The stockmarket for instance defines groups and companies in key groups of core business. The expectation is that companies toe the line and do not diversify across their areas of defined expertise. In essence, the market has given notice that the requirements are to focus and stick to our core business. So what right does the conference have to suggest that diversity is the key to prosperity. Hasn't the organiser read the book, studied the history, listened to the market - obviously not. Have they got it wrong, My feeling and belief is no - the organisers have got it right. However, the matter is not as simple as first perceived. What is Diversity, or Diversification as I would prefer? Is it a product position? Is it a geographic position? Is it an expansion or change in services offered? Does a gold mining company diversify into copper or diamonds or aluminium or nickel? Does a gold miner in Australia diversify into China or Kazakhstan or West Africa? How do the two relate? They don't. A successful company will always possess a 'core competence' not so much a 'core business'. The best example of this is the service company extraordinaire - McDonalds. They don't sell hamburgers or french fries, they sell a service, a convenience, a lifestyle. The core business is hamburgers and if McDonalds were to diversify further into new styles of hamburgers, I suggest to you they would fail. But if McDonalds were to diversify into other products based on their 'core competence', provision of service, then I would suggest to you they would be very successful. The service procedure, service machine, service system, the formula, stava the rnnetant the nrnrlnrte -

Jan 1, 1996