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I have headed this paper with a question and for the impatient among you ûthe answer is no we have not run out of developments but, and it is a big æbutÆ, we need to be innovative and ahead of the game or ænoÆ will be æyesÆ before we know it.Why do I believe that our future lies in innovation? Thirty years ago, knowledge doubled every 14 years. It is now doubling every seven years. In 1965, Gordon Moore, one of the founders of the chip maker Intel, made an observation that growth in memory chip performance is doubled every 18 months which became known as MooreÆs Law. Now there is fibre law, where the transmission line capacity doubles every nine months and storage capacity, under disc law, doubles every 12 months. What does this mean? Well, firstly there is a massive rise in information flow and availability with no limits in growth for at least the next ten years. Secondly, unlike our grandfathers, we are most unlikely to be employed by the same firm for our working career - we may not even have the choice to stay with the same company. In a phenomenon Richard Foster and Sarah Kaplan (2001), borrowing from Schumpeter, termed æcreative destructionÆ, companies are unable to sustain market-beating levels of performance for more than ten to 15 years. In the 1920s the turnover rate of companies in the United States was 1.5 per cent, so a company could employ almost three generations from the one family. A company had a half life of 60 years. In other words, you could well be in the same working environment as your grandparents. Today the churn rate is estimated to be eight to ten per cent. A company has a half life of five to six years. So for large companies, as an employer or employee or as a contractor, your working environment has a 50 per cent chance of changing in five years. Innovation is the driver of this rapid rate of change. Innovation is not for the faint hearted (Cutler, 2001) but it is the core for success in the global economy. The rate of change in our world is not going to decrease. We must learn, not only to manage change, but to enjoy the process of changing û to ride the tsunami of the knowledge economy.

Jan 1, 2002

By K Osman, P Bennett

The mining of an underground orebody requires development both in waste and ore before stoping commences. Regardless of what metal is being extracted, the waste development is minimised to reduce the cost per unit of metal mined. At the Western Metals Zinc Kapok mine site, reducing the cost per tonne of lead and zinc mined is paramount. Decline waste development costs can be minimised by methods such as increased gradient or reduced drive size. Ore development will also involve some mining of waste. The degree to which waste mining can be minimised will depend on the thickness and dip of the orebody. The drive geometry will also determine the percentage of waste within the face. It is by mining methods such as resue mining that selective mining may be used to maximise the amount of metal mined and reduce waste dilution. Resue mining can be used around a set of selection criteria established by the mine site. These selection criteria will determine how resue mining can be applied to the mine site. Selection criteria include firing times, number of headings available, acceptance criteria for percentage lost metal, dilution and most importantly operator acceptance. The single pass or two pass resue mining method should be chosen depending on the site acceptance criteria and selection criteria. The Western Metals Zinc Kapok mine site has established a set of parameters which accept the two pass resue mining method for the mining of the ore drives. The blasting results from a single pass resue method were reviewed during more recent trials in a single heading. Through a comparison of results, the parameters allowed the decision to determine the applicability of resue mining and its current form to Kapok. This paper outlines the parameters set by the Kapok mine site, reviews these in relation to the two forms of resue mining and examines the criteria which make this mining method applicable for Western Metals Zinc.

Jan 1, 2002

This paper describes the technical development of the Newman beneficiation plant over its 23 years of operation and how this development relates to the mine ore reserves of high-grade and low-grade ore. It also discusses the importance of the beneficiation product grades in the overall blending of shippable products from a range of mines to optimise overall ore resource utilisation. Also discussed is the importance of the ore reserve reconciliations in resource utilisation. Data is provided on the capacity and quality improvement results of the plant upgrade, carried out in 1999. This shows how the original capacity upgrade targets have been exceeded and the additional quality benefits that have been obtained from this capacity.

Jan 1, 2002

By P. J. van der Walt

The paper1(hereinafter BG) by two respected sampling experts contains sound theory and logic that can?t be directly refuted. Nevertheless, a practitioner knows that there is a broader context in which the practice of sampling takes place. This broader context, being less well defined than the theory of correct sampling, receives correspondingly less exposure which this commentary??prompted by? BG?seeks to rectify. ?Correctness? of a sampler is the central concern of BG, where it is presented as a sharp ?black-and-white ?distinction. Accordingly, comments below are grouped under the following headings: ?Correctness in practice ?Without correctness, what can be done? ?The broader context.

Jan 1, 2002

By T Mattiske

The Fimiston Open Pit (commonly referred to as the æSuper PitÆ) is a part of the Kalgoorlie Consolidated Gold Mines Pty Ltd (KCGM) operation in Kalgoorlie-Boulder. KCGM manages the Fimiston Open Pit, the Mt Charlotte underground mine, the Fimiston Mill and the Gidji Roaster for its Joint Venture Owners, Newmont and Barrick Australia. KCGM produces up to 850 000 ounces of gold per year. The KCGM operations are located on the historical Golden Mile on the outskirts of the City of Kalgoorlie-Boulder, about 600 kilometres east of Perth Western Australia. This traditionally underground mining centre has been worked since 1893, yielding in excess of 50 Moz of gold from ore with an average head grade of 10 g/t. This represents approximately ten per cent of the gold produced in Australia and one per cent of the gold produced in the world. The Fimiston Open Pit is essentially an aggregation of what were known as the Judd, South, Paringa, Croesus/Eclipse, Central, Brownhill, Drysdale, Morrison, North and Horseshoe pits into one continuous large-scale operation. The old Fimiston Underground Operations (included the Main, Croesus, Chaffers, Lake View, and Perseverance shafts) were also located within the area of the Fimiston Open Pit. The underground operations closed in 1992 due to high mining costs.

Jan 1, 2002

Every step on the path from the mine to the smelter invites a comparison between material inputs on one side and outputs plus accumulation on the other. Or put simply, between what you think you have produced with what you find you have at hand. The discrepancy between these sets of comparisons is the error. Following that error in a systematic and objective manner is a way to improve the mineÆs measurement systems, that in turn leads to more accurate accounting for ores, metals and concentrates. Because the control of production is so tightly coupled with the accounting of materials, any lasting improvements in materials accounting will benefit the predictions of materials movements and quality. This translates to more reliable planning and scheduling in stockpile management, logistics, shipping and marketing. The statistical tools described are direct adaptations from the long-standing methods used to maintain the quality of manufactured product in the discrete parts industries. Their use in the process industries, of which mining is one, requires some care owing to the continuous nature of ore extraction and its variable properties. The tools can be used for problem diagnostics and as early warning systems. In common practice many professional staff, in attempting to get a perfect reconciliation between expected and observed results, try to explain away the error or bury it completely. The methodology advocated here requires a different mindset because the error must be given pre-eminence for lasting improvement to be realised.

Jan 1, 2002

I would like to start by thanking The AusIMM and CSIRO for organising this excellent conference and inviting me to give a keynote address. Today I will focus on some broad observations of our industry, and leave the technical discussion to my colleagues who are presenting specific papers covering a wide range of topics. In preparation for this paper, I did a little research into the early history of the Pilbara iron ore industry. I was fascinated to read a quote attributed to Harry P Woodward, the Government Geologist in the late 19th century, before Federation. Mr Woodward described the Pilbara as an iron ore country and observed that æthere is enough to supply the whole world should the present sources be worked outÆ. Mr WoodwardÆs prediction could be viewed as wishful thinking and certainly at Hamersley Iron I would gladly envisage the Pilbara supplying the worldÆs entire iron ore needs! In reality, Western Australia accounted for 162 million tonnes or 36 per cent of seaborne trade in 2001. An impressive effort, but not quite the total world supply as Mr Woodward imagined. But we shouldnÆt dismiss these historical musings out of hand û perhaps we could see it as a challenge for the industry to æwork outÆ the present sources. We all know there is abundant iron ore in the Pilbara, and I expect it is only a matter of time until our collective technical expertise and sheer hard work will enable us to utilise its greater range of ore types. Opening up new markets will be a key pathway to creating additional value from the Pilbara ores. Today I will examine the state of play of our industry and the major influences that shape our business at present, before considering what the future might hold for us. I canÆt guarantee the accuracy of my crystal ball, but the stability and long-term nature of our industry does enable some reasonable hypotheses on where we are heading. I will also spend some time examining the way in which the iron ore producers are working to maximise the value of their resource base and obtain more from their existing capital assets.

Jan 1, 2002

By FM Murray

SAFEX International is a global organisation with more than 85 members, all of whom are manufacturers of explosives. On joining each member signs a declaration saying that they are willing to exchange information with regard to any accidents or near misses they may have in order to prevent the recurrence of the incident. SAFEX International was formed 50 years ago in Europe and has now built up a database of more than 700 accidents in the explosives business. Once every three years, an International Congress is held in which members address specific safety themes associated with the explosives industry, and also give details of "what went wrong?", "why?", and lessons learned. The next Congress will be held in Amsterdam between the 29th May and the 1st June 2002. This paper describes the operation of SAFEX International, which is dedicated to the international exchange of experience on industry connected accidents of the explosives business.

Jan 1, 2002

Equilibrium calculational software programs can be effectively utilized to illustrate the importance of activity or concentration, solubility, temperature, solution pH, solution potential, and ligand complexation to students studying hydrometallurgy. The calculational program STABCAL will be demonstrated. illustrative examples for the creation of diagrams such as EH-pH, activity or concentration-pH and activity or concentration-EH will be presented to demonstrate the fundamentals of real hydrometallurgical systems. Speciation, titration and mixing will be used to simulate or predict operational processes. Applications will include treatment of Acid Mine Drainage (Berkeley Pitlake water and sediments), mass balance potential/pH diagrams, leaching and selective separation of metals from electroplating sludge, metal adsorption at femhydrite surfaces, and flowsheet development for treating mercury sulfide K106 sludge.

Jan 1, 2002

By R Billingham

QueenslandÆs new safety legislation for metalliferous and coal mining (Mining and Quarrying Safety and Health Act 1999 and Coal Mining Safety and Health Act 1999, together with the Regulations) came into effect on 16 March 2001. The legislation places clear obligations on mine owners, operators and workers to have a safe place of work and to manage risks to safety and health. It also places obligations on contractors, designers and providers of services. The legislation is non-prescriptive in that it states what outcomes must be achieved and not what must be done. The key issue is that the risk of injury to people must be at an acceptable level. The legislation creates a Mines Inspectorate with powers of inspection and audit of mines, their safety management systems and the management of risks. Auditing of the risk management process is carried out against standard risk management techniques and directives for corrective action may be issued when audits reveal non-compliance or unacceptable levels of risk.

Jan 1, 2002

By A. P. Squelch

The question of what stress condition exists in the hangingwall of tabular stopes remains topical and largely unanswered. Limited field data exist to quantify the situation and provide calibration for investigative computer modelling exercises. Work conducted in1989 and 1990 under a Chamber of Mines Research Organization (now the CSIR: Division of Mining Technology) programme of research into the behaviour and benefits of backfill may assist with this situation. The original work was motivated by the premise that the improved hangingwall stability in backfilled panels (identified by rockfall accident analyses) is due to a change in the hangingwall stress regime. Current, largely theoretical, studies into mechanisms of stope hangingwall behaviour and support interaction could benefit from considering these data. Keywords: Backfill, horizontal stress, stope hangingwall, hangingwall stability, support interaction.

Jan 1, 2002

By Malcolm Powell

"The argument has long raged across the oceans as to what the best AG/SAG mill aspect ratio is. The North American practice of a high aspect ratio of two, diameter twice length, through to the South African and Scandinavian practice of an aspect ratio of as low as a 0.5. Within the collaborative P9 AMIRA project the MPRU of the University of Cape Town and the JKMRC of the University of Queensland have been collecting plant data pertinent to this issue over the past four years.The JK SAG mill model developed by the JKMRC is based upon data collected from mills having a range of aspect ratios from 1 up to 2. The maximum mill speed, mill load, and ball filling in the fitted data base were all below the operating range common in South Afr-ica. The extension of the P9 project into South Africa therefore lent an ideal opportunity to collect data in a whole new window of operation that would allow the range of applicability of the semi-empirical SAG model to be greatly extended.At the heart of the differences in aspect ratio is the completely different operating practice for high- and low- aspect mills. The mill filling, mill speed, and recirculating loads of closed-circuit single-stage operation have more influence on the differences in operation than the pure aspect ratio relationship. Relationships for load have been extended to 45% filling, with the modified model showing the measured peak in throughput as the mill filling increases. The ball load relationship now covers fillings of over 30% balls (of total mill volume), thus including so-called SAG-ball mills. The influence of closed circuit operation has been measured. It has been found that a key issue of the high slurry flows associated with closed circuit operation, especially when closed with a cyclone, is the pulp discharge limitation of the traditional grate and radial lifter configuration. It has also been observed that absolute mill length is more of an issue than aspect ratio. Slurry flow along the mill and charge segregation within the load are being investigated on pilot and full-scale mills to provide data for potentially modifylng the perfect mixing model that is used for the SAG mill.Improved understanding of these aspects of SAG mill operation and extension of the JK SAG model to better cover the entire range is allowing serious direct comparison of high- and low aspect mills for the first time. It is the conclusion of the researchers working in this area that there is no one best practice, that in fact mills across the range have their application based on ore type, desired product, available capital and on operating costs. Developing robust designs allows direct comparison of two-stage circuits using high-aspect primary SAG mills, with single-stage closed circuit low-aspect SAG mills. The new operations within South Africa are now considering both circuit types, and data is presented on selections that cover the full range of aspect ratio and operating practice."

Jan 1, 2002

By Roland Heersink, Charles H. Wells

This paper discusses how a mill uses off-site data hosting approach to effectively utilize an entire suite of advanced applications to optimize daily operations, without incurring the overhead of on-site systems, staff and support. Details of the solution are provided, together with a live view of actual plant operations. Security and authentication mechanisms are also outlined so that users may gain an appreciation of the actual security of the remotely hosted data. A number of Web-hosted software applications provide direct connectivity to the database offering rapid and deterministic response times to clients. A 24x7 help-desk is available to authorized users from any Internet connected device. The paper shows how mill management advantageously use wireless PDA's to view what is going on at anytime and from anywhere. It concludes with a summary of how the approach is being used to speed decision-making and capture spot market opportunities.

Jan 1, 2002

By L. Hagenbuch

Off-highway truck purchasers know the amount of tonnes, pounds, kilograms, etc, a truck will carry. However just because a truck is rated at 240 tons may in no way correlate to what that truck will actually carry. Two numbers define the carrying capacity of an off-highway truck: 1. The weight carrying capacity of the truck; 2. The volume carrying capacity of the truck. These two numbers must be in sync or the amount of payload carried will vary from the carrying capacity of the truck. Currently the Society of Automotive Engineers (SAE) standard J1363 January 1985 defines the volumetric carrying capacity of an off-highway truck. However as is well known in several South American countries, the SAE standard overrates the truck’s effective volumetric carrying capacity 15% to 20%. This paper presents a method for measuring “effective” body volumetric carrying capacity, resulting in a truck body for carrying the targeted load, matched to the loading equipment that interacts positively with the truck chassis.

Jan 1, 2002

By M Barley, C A. RosiFre, L Lobato

The Carajßs iron ore deposits contain approximately 17.5 billion tons of ore with >64 per cent Fe and occur in the eastern part of the Amazonas Craton. They are hosted by jaspilitic banded iron-formation (BIF) of the Carajßs Formation which, together with metavolcanic rocks, comprise the ~2.75Ga Grpo Parß Group of the Itacai·nas Supergroup in the ~1000 km long, E-W trending Carajßs Synclinorium. The Carajas Formation comprises discontinuous layers and lenses of partly dolomitised BIF (17 - 43 per cent Fe and 35 - 61 per cent SiO2) and lenses of high-grade iron ore, cut by mafic sills and dykes. The high-grade iron ores occur as large tabular bodies of friable (soft) hematite with smaller lenses of hard (compact) hematite. The hard hematite ores typically occur at the contact with the underlying volcanic rocks and are surrounded by an aureole of hydrothermal carbonate alteration. BIF that has been overprinted by dolomite and magnetite crystallisation has recently been discovered at depth in the N4E Mine. With increasing amounts of carbonate, the original lamination (microbanding) and other fine primary structures in the BIF have been progressively obliterated resulting in alternating carbonate and iron oxide mesobands. The friable hematite ore that is characteristic of the Carajßs deposits results from ongoing weathering and leaching of the carbonates from this type of altered BIF. The hard hematite ores probably result from more extensive early oxidation. The association of both carbonate-altered and jaspilitic BIF with the N4 Mine is similar to that observed at the Mount Tom Price deposit in Western Australia, where carbonate-altered BIF occurs below massive hematite ore with a jaspilitic halo developed above the orebody. This indicates that as at Mount Tom Price, hydrothermal carbonate alteration and associated loss of silica from BIF may be an important step in the formation of these giant hematite deposits.

Jan 1, 2002

By Wes Bender

Considering the current interest in Global Positioning System (GPS) usage, it might be timely to look at a more efficient means of utilizing these instruments. The GPS system currently utilizes 28 satellites (4 are spares) circling the earth in an inclined orbit. Normally at least six satellites are within your area of reception at any given time. The satellites broadcast an extremely accurate time signal and an almanac containing all the satellites’ orbital data. This information is updated regularly as the satellites circle the earth. Your GPS receiver, once it has picked up one satellite’s broadcast, can then determine which other satellites should be available for plotting.

Jan 1, 2002

By H. O. Seigel, J. C. Gingerich, E. O. Köstlin

"To satisfy their continuing need to replenish or expand their ore reserves, mining companies are faced with the dilemma of arriving at a proper balance between the dual avenues of discovery through in-house exploration and of acquisition of properties that are relatively proven or are even in production. The returns from exploration activities may be spectacular, but are unpredictable. The allure of an acquisition lies in its promise of quick and risk-reduced addition to reserves. However, it is historically clear that quantum increments in shareholders’ values have arisen primarily through major exploration discoveries, rather than through major late-stage acquisitions. Late-stage acquisitions can prove highly profitable, sometimes based upon the planned use of superior mining or metallurgical technology, but more often occur as the result of unexpected windfalls. At the other extreme, they can become expensive failures through inadequate due diligence, or unforeseeable factors.Citing numerous case histories and industry statistics, it is concluded that a judicious combination of both exploration activity and the acquisition of prospects is the most advantageous strategy for adding new ore reserves. A skilled exploration staff is essential for success, be it through exploration discoveries or through opportunistic acquisitions, preferably at their early stages. In the future, it is anticipated that there will be fewer opportunities for acquisition because of reduced funding for junior exploration companies, leading to increased competition and higher costs for fewer properties, both in the advanced exploration and mining stages."

Jan 1, 2002

By W. Kasprzak

Modern light metals processing technologies are very complex and involve a diverse set of variables that must be quantitatively evaluated. The most effective way to design new casting processes that deliver specified metallurgical and mechanical properties is to develop a method of simulating the "real-time" process within a test sample of sufficient size. The results can then be analyzed and the required optimizations can be performed. This paper presents a novel method of simulating the industrial casting processes in a laboratory environment using an experimental apparatus based on the principle of high frequency induction heating. The applicability and accuracy of the proposed analytical method is demonstrated, for example, by simulation of the solidification and heat treatment of a test sample composed of two dissimilar materials. The simulation can be used to develop a stress model for an engine block made from an aluminum based alloy with iron cylinder liner inserts.

Jan 1, 2002

By Patrick R. Taylor

A non-transferred arc thermal plasma assisted cyclone reactor has been designed, built and operated to evaluate its use in vitrification of wastes. Simulated waste (liquid, slurry or fine particulate) is injected near the plasma flame, where nearly instantaneous dehydration and calcination reactions happen. A non-transferred arc plasma torch was attached tangentially to the cyclone and is utilized as both an enthalpy source and to provide the gas velocities required to generate the cyclonic gas flow patterns. The closed top cyclone flow sends the solid particulates to the wall, where they are captured by a thin film of molten glass that is injected as a powder at a position lower in the reactor. The molten glass is then collected in a crucible. The feasibility of simulant injection directly into the flame zone and its effect on electrode lifetimes has been studied. Several candidate refractory systems have been evaluated for their suitability for extended use under the demanding conditions present in the cyclone reactor.

Jan 1, 2002

Production sharing and cost apportionment in joint ventures is commonplace in Australasia today and elsewhere. It is a recognised convention that, with the exception of a free carry situation, joint venture participants usually share the proceeds of the joint venture in direct proportion to their respective participating interest, after having first paid its respective cash calls, in advance, to cover the projectÆs ongoing operating and capital cost requirements.In surface mines, the parties simply pay their way and take their proceeds in this manner. In underground mines, the situation is no different, though treatment of capital, depreciation and tax may differ between the parties. A common feature in many cases is the creation of a joint venture entity to conduct the business. This entity then collects cash from the parties, banks it, employs the staff, runs the operation, provides reports and pays out the proceeds. This convention appears to be relatively simple in application. In practice, it has been known to be complicated in the situation where the participants take their product at the mine gate and undertake their own marketing and selling arrangements. A more complex situation presents itself where the joint venture tenement boundary with an unrelated third party straddles an economic deposit. In this scenario, both the joint venture parties and the third party may wish to mine the deposit, sharing some infrastructure and costs, yet taking their own product as it is produced. A case study outlining such a situation is presented in the paper, outlining firstly how the major cost categories were identified and treated for cost apportionment purposes. Secondly, a mechanism for the equitable apportionment of product is suggested. Finally, issues such as timing and cost reporting are dealt with, together with a checklist of points which should be considered when a similar situation might arise in the future.

Jan 1, 2002