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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 Scott B. R

Bougainville's copper mine is located on the west slope of the Crown Prince Range on Bougainville. A high grade copper concentrate is produced for sale to overseas customers. Production planning which was originally based on pilot plant data has developed progressively since commissioning of the concentrator in 1972. Pilot plant data and mine sampling have been supplanted by the correlation of concentrator performance with ore sources, as the basis for short term planning. The influence of accurate sampling is reflected in 1. hourly shift control, 2. the daily milling statement, 3. the prediction of the characteristics of ore from various mine locations, 4. production reconciliation, and 5. the control of copper losses. The mechanical and electrical failures of the original sampling system emphasized the need for a reliable, automatic sampling facility. The development of a pneumatic drive mechanism, which has now been fully field tested, was undertaken.

Jan 1, 1976

This paper details a proposal for integrating the use of the Pilbara Iron Ore Classification (PIOC) and stratigraphic data for fine tuning blast. pattern design on Mt Whaleback. The main thrust of the proposal is based on the assertion from Haqan and Harries (1979) that rock properties influence blasting results more than explosive properties. This premise is supported by a literature search, which indicated that blasthole burden, spacing, stemming and subdepth lengths are also determined by rock properties if the same explosive and blasthole diameters are used. A brief explanation of the PIOC is provided during which it is noted that the classification is based on physical hardness, mineralogical and genetic characteristics of the ore. The classification also extends to the two main waste rock types LBIF (banded iron-formation) and shale]. Ore type plans produced from face mapping indicate that many areas on Mt Whaleback can be divided into various PIOC zones and regions thus making it more useful in blast pattern design. Several recommendations for blast pattern design experimentation are made for hard, medium and soft ores as well as for the waste rocks, the most important being the use of expanded patterns to blast. soft BIF and medium hard to soft shales.

Jan 1, 1986

This paper traces briefly the reasoning which led to the decision to extend the existing internal shaft at the Rosebery Mine and to instal underground a larger winder (No. 2 Hoist) with capacity to handle all hoisting requirements to a depth of approximately 2,500 ft. on an incline varying from 83" to 55" to the horizontal. It then covers the specifications and selection of the winder, the design of the winch chamber, rope raise and bins, the excavation, support and lining of the chambers and the transport to site and installation of the machinery. Finally a brief description is given of the mechanical and electrical parts of the winder.INTRODUCTIONThe existing shaft winder on the internal inclined shaft situated on No. 8 Level of the Rosebery Mine had reached the limit of its capacity. Hoisting 21-ton capacity skips in balance, with a 13/16-in. diameter rope, it required four layers of rope on the 3 ft. 6 in.drums to reach the loading station under No. 12 level at a depth of 864 ft. (Fig. 1). This entailed heavy wear on the multi-layered rope and heavy stresses on the cheeks of the drums. Continuous working on three shifts was necessary to handle ore, men and materials, and a hold-up from any cause whatever meant an interruption to production on the lower levels of the mine. The maximum output of the hoist whilst hoisting from the No. 12 level loading station was 50 tons per hour. It was obvious therefore, that a larger winder was required if output was to be maintained.Diamond drilling had proved the existence of sufficient ore at depths well below No. 12 to warrant exploitation and a decision had to be reached on the means of hoisting this ore.

Jan 1, 1958

By Henderson N, Schaap H

In large companies with mining operations spread over multiple sites, it is essential that consistency between sites is maintained in preparing and classifying resource and reserve estimates. The endorsement by The AusLMM and AMIC of the "Australasian Code for Reporting of Identified Mineral Resources and Ore Reserves" and the subsequent incorporation of reference to the code into the ASX listing rules for mining companies has provided a basis for the consistent classification of resources and reserves. However, compliance with other criteria more or less stringent than the Australasian Code can present some reporting difficulties. Examples include listing requirements for foreign stock exchanges, particular Acts of Parliament that may apply to individual leases, constraints imposed by individual companies on their own leases, and ultimately, reserves for short, medium and long term planning. Confusion can arise when any two or more sets of reserves for the same lease are compared.. To alleviate this confusion, a standardised procedure was developed for the calculation and classification of coal resources and reserves. The procedure which is geostatistically based incorporates a technique called "Irregular Block Kriging" where specific mining blocks are directly kriged. The procedure has enabled those engineers and geologists with only a basic understanding of geostatistics to apply the technique and not feel hampered by some of the complex mathematics which in the past has tended to inhibit and overcomplicate the use of geostatistics. The procedure has resulted in "cleaner" data bases and hence more reliable reserve estimates.

Jan 1, 1990

By G Milligan

This paper describes how water is being planned, managed and used in Queensland as both a precious natural resource, vital for healthy ecosystems, and as a valuable tradeable commodity, necessary to secure economic prosperity. Queensland has been progressively implementing a planned package of water industry improvements agreed by the Council of Australia Governments in 1994. The Water Act 2000 provides the legislative basis for implementing the COAG water reform framework in Queensland and sets out statutory water planning processes. A Water Resource Plan (WRP) is a strategic document that specifies water sharing and environmental flow outcomes across a whole catchment over a period of up to ten years. A Resource Operations Plan (ROP) sets out the details of implementing a WRP, including environmental flow rules, establishment of tradeable water allocations that are separate from land, rules for water trading, rules for operating water infrastructure, arrangements for the release of any unallocated water identified in the WRP, and requirements for monitoring and reporting. Water Resource Planning and Resource Operations Planning are progressing in priority catchments and aquifers across the State. Ways to obtain a water entitlement now depend on whether a WRP and/or a ROP exist in a particular catchment. Water trading provides for the buying and selling of water entitlements on a permanent basis where permitted under a ROP. Details of tradeable water allocations are securely registered on the Water Allocations Register, which is similar to a land titles register. Leasing and temporary transfers of water entitlements are also possible. Water brokers are emerging to facilitate water trading which aims to improve water use efficiency and move water to higher value uses. Queensland is leading the way in the implementation of the COAG water reform framework and the pursuit of sustainable water resource management. The StateÆs progress in this regard is increasing certainty for water users, while ensuring that considerations of equity amongst existing and future users and amongst various uses, as well as considerations of ecological sustainability and the wider community, are all taken into account. The mining sector stands to benefit substantially from these new approaches to planning, managing and using this precious resource.

Jan 1, 2003

By Brockway DJ, Holmes RJ

A natural gamma-ray gauge has been devel- oped for discriminating overburden and inter- seam sediment from low ash coal located on a moving conveyor belt. It is based on the difference in natural radioactivity of the sediment and overburden compared with the low ash coal, which is detected with a highly ef- ficient "Polyscin" NaI(T1) gamma-ray detector located underneath the conveyor. Gauges have been successfully installed on the bucket wheel boom of the two coal dredgers at the Loy Yang Open Cut. They are used to warn dredger operators that they are digging overburden or sediment and that action is required to avoid the sediment or divert it to the waste dump rather than send it to the coal bunkers at the power station.

Jan 1, 1987

Since the 1970s we have seen a marked corporate response in terms of the environment. In part this has come from regulation but it has largely come from stakeholders and the community. We now see a similar trend towards sustainability. The Brundtland (1987) definition of sustainable development provides a direction for advocates: the advance of human prosperity in a way that does not compromise the potential prosperity and quality of life for future generations. In my view its three essential components are: economic, environmental and community. The Global Mining Initiative and the contributions to the Rio World Summit and the Johannesburg World Summit on Sustainable Development indicate that sustainability is being taken very seriously by the mining industry. But does the minerals industry really embrace sustainability as they claim? There is a view that in reality sustainability is a non-event and that the triple-bottom line approach is only a convenient catch-cry for companies who are actually focussed very strongly on the economics part of the equation. Chemical engineers are showing a strong trend to more sustainable practices and the chemical industry has shown real commitment to research into developing sustainable processing systems. This requires a framework for thinking and design and the chemical industry is demonstrating true innovation as it moves towards æno wasteÆ technologies. Whilst there are limits to the rates of change that can occur the minerals industry should also be moving in a much more determined manner towards the notion of processing of products designed for whole-of-life cycle û with minimum/no waste. But is the minerals industry just paying lip service to the importance of research to sustainability?Several common themes influence the science and innovation agenda in Australia, which will affect the development and adoption of innovations by AustraliaÆs minerals sector. First is the well-proven link between peer-reviewed scientific excellence and commercial application. Second is the rise of multi-disciplinary Mode 2 research, which has developed in response to the complexity of problems faced by contemporary researchers, which are best analysed by combining expertise from two or more disciplines. Successful innovation outcomes, in any field, including minerals processing, is promoted by Mode 2 research which benefits from greater levels of networking and collaboration. Kofi Annan in his Message to the World Social Forum puts it very succinctly æThe way forward lies in finding constructive solutions togetherÆ.

Jan 1, 2004

By M Noy, P Hawkes

Improvements in the drill and blast process can impact on loader performance in a number of ways. The main effects being improved loading cycle times, less non-productive cycles such as oversize removal, clean-up and face raking and better bucket fill factors. The impact of improved loading cycle times on the overall cost and productivity of the load and haul cycle is very much dependent on the loader truck match and the management of the haul fleet. Previous work has shown that a 20 per cent improvement in dig cycle times may only lead to three per cent or less improvement in the overall productivity of the load and haul process. However, improving the mass loaded per pass by five per cent will lead to a five per cent improvement in productivity for any given haul fleet situation, assuming sufficient truck capacity. Work by Orica Explosives at Lab ChrysotileÆs Thetford Mine, Quebec, Canada showed a relationship between muckpile fragmentation and truck payload. With this in mind, work was carried out to determine the effect differing muckpile fragmentation distributions can have on excavator bucket fill factors. This work was performed in the laboratory to a 1:100 scale. Nine different distributions were used. These were characterised by the Rosin Rammler parameters, xc the characteristic size, and n, the uniformity index. The values of xc and n used were modelled on those previously measured at a Sydney quarry. For the range of distributions measured, it was found that the fill factors were lowest at a low characteristic size and a high uniformity index and highest at a high characteristic size and a low uniformity index. In other words the best fill factors were achieved with a more dispersed muckpile distribution with a larger characteristic size. The difference in fill factors was 16 per cent indicating that controlling the drill and blast process to produce a specific muckpile distribution can have a significant impact on the overall cost-efficiency and productivity of the load and haul process. Field measurement by Orica Explosives at a quarry in Canada supports this conclusion showing improvements of up to seven per cent in average bucket load by either increasing the characteristic size or decreasing the uniformity index of the muckpile.

Jan 1, 1999

The sole reason for a mine to exist is to extract the finite mineral resource. Accurate grade control is critical to the economics of any mine. If grade control is not optimised, then no matter how good the downstream processes are, the full potential of the operation will not be realised. The detailed implementation of grade control varies but typically consists of sampling and assaying to determine the location of the ore zones. A lot of time, money and effort are spent defining the location of the ore as accurately as possible à but then it is blown up! The effect that blasting has on grade control is rarely adequately accounted for when the rock is excavated because there has never been an accurate and practical method for measuring blast movement. This paper draws on over six years of research into measuring and understanding blast movement, which started at the Julius Kruttschnitt Mineral Research Centre (JKMRC) of the University of Queensland. The research has made a unique contribution to open pit blasting by helping to develop a practical tool for measuring blast movement, which was then used to improve the understanding of three-dimensional blast movement dynamics. However, these achievements would be of largely academic interest without taking the final step of using this technology and knowledge to account for blast movement by translating the ore polygons in response to the measured movement vectors. This paper provides an overview of blast movement but focuses on one site where blast movement was measured during three separate periods, with significantly different orientation of the mineralisation on each occasion. The theoretical ore loss varied from nine per cent to 24 per cent. The differences are primarily due to the orientation of the ore polygons relative to the direction of movement. The optimum grade control solution is a combination of accurately accounting for blast movement and designing appropriate blasts.

Jan 1, 2009

Chile, which hosts around 30 per cent of the worldÆs copper resources, is now the largest producer and exporter of copper. Chilean copper output accounts for more than one-quarter of total worldwide production. An increase to around 40 per cent is forecast by the end of the century. In addition, Chile ranks eighth in silver production and 11th in gold output. In Chile, mining generates more than eight per cent of the countryÆs GDP and the total value of mineral exports is more than US $7.85 billion corresponding to more than 25 per cent of South AmericaÆs mineral production. The rate of growth of Chilean mineral production is indeed impressive. Table 1 shows that in the period 1969 - 1998, copper annual production increased 564 per cent from 667 000 t to 3 764 000 t. Gold production went up 27 times from 1827 to 49 770 kg. Silver output grew 1219 per cent from 95 650 kg produced in 1969 to 1 166 380 kg in 1998. Several facts explain this dramatic increase of production, but the most important was the success of exploration sustained over the same period. This resulted in the discovery of several world-class deposits which when developed into mines, account for much of the production increases. Therefore, this summary review shows the success of basic exploration carried out during the last 30 years in the Chilean territory. The review is based on data already published in different specialised mining books or magazines. It only includes those world-class discoveries not the lesser discoveries important at local scale. All figures were calculated using 1998 $US dollar and average estimated metal prices valid for 1999: copper $US 1653 per t ($US 0.75 per pound), gold $US 9452 per kg ($US 294 per ounce) and silver $US 177 per kg ($US 5.5 per ounce).

Jan 1, 1999

By Stille H

The choice between drill and blast and mechanical boring methods is often not obvious. There are several factors which may have a de- cisive influence on this choice, such as the geometry and length of the tunnel, site con- ditions and borability of the rock. Both the un- confined compression strength and the joint dis- tance have a considerable influence on the net penetration rate. Site conditions, rock quality and water conditions influence the utilization of the tunnel boring machine. The drill and blast method is normally less sensitive to devi- ations from assumed ground conditions.

Jan 1, 1987

By Moon N. T, Torrance A. C

This study has considered the effect of mechanical shock on the resilience of the glass microspheres commonly used to sensitize an explosive emulsion. The damage to the glass microspheres caused by detonating cord, emulsion manufacture and the manufacture of the glass microspheres were considered along with the effect of sensitizer concentration on explosive performance. Reductions of up to 50% in the glass microsphere concentration of an emulsion explosive can result from poor initiation practice, such as the use of high strength detonating cord as downlines during initiation. Laboratory results suggest that detonating cords of strength greater than 3.5 g/metre should not be used as this can seriously affect explosive performance, particularly in small diameter charges. This reduced performance results from damage to the sensitizer elements and recrystallization of part of the emulsion phase.

Jan 1, 1990

A novel solvent extraction process, called the SOHNEX process, has been developed at the University of Utah. In this process, the organic and the aqueous phases flow countercurrently in a horizontal vessel, and the emulsion between the two liquid phases is generated by high-velocity gas jets injected at the bottom. The gas jets are located at certain intervals along the bottom of the vessel with phase disengagement zones on either side of the plume zone created by the gas jet. The system is simple, having no mechanical moving parts or complex internal structures, and yet provides good contact between the phases with minimal backmixing. Tests have shown that emulsions with a wide range of specific interfacial area, including that typically encountered in mixer-settlers, can be generated in this process. It has significant built-in flexibility of operation including the control of the flowrate and hold-up of each liquid phase. The SOHNEX process overcomes the difficulties in the operation of conventional solvent extraction equipment such as mixer-settlers and column extractors. A major advantage of the SOHNEX process is that the energy of mixing can be closely controlled by adjusting the strength of the gas jet. This allows an optimal control of the drop-size distribution of the dispersed phase and thus the specific interfacial area. The process is continuous, and any number of extraction and separation stages may be built into a single vessel. The gas can be recirculated in a closed loop, thus eliminating solvent loss and mist problems, especially for high-temperature operations. The SOHNEX problem can handle solutions that contain suspended solids and that form third phases. The simplicity of the equipment and operation with low maintenance will mean much reduced capital and operating costs as well as low environmental risks and improved safety. The SOHNEX process has been tested for continuous copper extraction from a dilute solution. Calculations also showed that uranium and other radioactive elements can readily be extracted in a small unit of the SOHNEX extractor while satisfying the nuclear criticality condition.

Jan 1, 2000

By Edwards A. B

This paper presents the results of an examination of four samples representative of the low-lead matte, high-lead matte, lead speiss and antimony speiss, respectively, produced during smelting operations at Port Pirie Smelters. The investigation was undertaken at the request of the Broken Hill Associated Smelters Pty. Ltd., as part of the research programme of the Mineragraphic Section of the Council for Scientific and Industrial Research.Analyses of the specimens are as follows:-

Jan 1, 1949

By Weyer J

Many existing computer planning programs for the mining industry focus either on big mining enterprises with a high production rate or on smaller operations for high value minerals. Big mining enterprises, like the hardcoal company `Ruhrkohle AG' in Germany have their own R&D departments which develop powerful computer programs for planning purposes, partly in co-operation with mining universities. However, there is a remarkable number of small- scale mining operations which are either not able to buy expensive hard- and software or don't have the skills for the operation of extensive software programs. Partly there is also a trend in using rule of thumb calculations rather than computer programs which need a lot of - partly unavailable - data. For this reason a computer program was developed which does not need expensive hardware and software and which can help the planning engineer in the selection of a limited number of possibilities. Until this time the planning engineer established two or three different cases and calculated the results with a pocket calculator. This could last some hours or even some days. Now he or she can use the computer program with a normal PC to compare the cases. All activities are menu-driven. The basis for all, calculations are fixed and variable costs as well as average performance for special activities. The paper gives an example for a possible planning situation in fluorspar mining (originally this program was developed for the fluorspar enterprise Lengenfeld in Germany). It shows the initial situation, the main structure of the program, the input logic and the results. Benefits, limits and possible extensions of the program are discussed.

Jan 1, 1995

By Yao S, Wang P, Zhang C

The Zhilingtou Au-Ag deposit is situated in the eastern part of the complexly deformed and metamorphosed South China Caledonian Fold Belt. It consists of seven orebodies that are almost exclusively hosted by biotite plagioclase gneiss of the Precambrian Chencai Group. They form an apparent en echelon pattern in both cross-section and level plan. Three different ore types, based on mineralization textures, have been recognized within the Zhilingtou lode. These are Au-Ag-rich quartz veins, Au and Ag-bearing silicified rocks and Au-Ag-containing altered rocks with quartz stockworks. The mineralization is principally composed of electrum, argentite, pyrite and minor sphalerite, galena as well as traces of hessite and chalcopyrite plus a gangue assemblage of quartz, rhodonite, sericite and chlorite. Fluid inclusions related to Au-Ag mineralization yield a wide range of homogenization temperatures from 110 to 447¦C, with two distinctive peak values at 250-300¦C and 350-400¦C respectively. S30Si values of quartz veins and silicification from the three stages of mineralization range from -0.1 to -0.4%o. The mineralization at Zhilingtou is interpreted as forming by recirculated meteoric water extracting ore-forming elements from metamorphic rocks due to Mesozoic volcano-magmatic activity.

Jan 1, 1995

THE South Mine. owned by the Broken Hill South Limited, occupies mineral leases 7 and 8 on the Broken Hill lode. The ore reserves are 4,250,000 tons, and the ore hauled for the year ended June, 1930, was 387,000 tons, the total to date being 7,840,000.The mine, down to the 1070-ft. level, is naturally divided into two sections, the northern and southern ends. Ore extraction is practically completed in the northern end to this horizon, while the southern end is developed ready for a concentrated attack.Fig. 1 shows the state of the 8215-ft. level, after connection to the new shaft.The levels above and below to the 1070-ft. level are in a similar condition, while below the 1070-ft. level the stoping has been confined to the north end, but not completed. The south end on these levels is also partially developed.The ore at present is hauled up No. 1 shaft, which is centrally situated to the present workings. This shaft was put into use in 1909, and in 20 years has had approximately 5,000,000 tons of ore pulled through it.The company, having proved the existence of large ore-bodies in the southern end of the mine, decided to sink No. 7 shaft. This is a six-compartment frame-set shaft (see Fig. 2) equipped with two cages and two 5-ton skips, the remaining compartments being utilised for electric cables, pipes, and ladders. The surface arrangements will include a steel head frame, electric winders, and breaker station.

Jan 1, 1930

By J B. Holman, P A. Weber, P Lindsay

Underground and opencast coal mining has occurred since 1896 on the Stockton Plateau, West Coast, New Zealand. Acid Rock Drainage (ARD) from historic and current mine workings has had an adverse environmental impact on the surrounding aquatic environment. The two main catchments affected by ARD from historic and current mine workings are the Mangatini and St Patrick Stream catchments. Solid Energy New Zealand Ltd (SENZ) is using active (e.g. alkali dosing) and passive (e.g. engineered cover) technologies to mitigate the adverse environmental effects associated with ARD contaminated waterways. This paper discusses the passive technologies. Principal strategies include the capping of high capacity potentially acid-forming volumes of overburden. The mudstones were found to generally have the highest sulphur levels compared to other overburden lithologies. Areas with high mudstone volumes are prioritised to be encapsulated and 390 Ha is planned to be capped in the Mangatini catchment in the near future.   Monitoring beneath granite, cement kiln dust and coal combustion product covers show oxygen can be reduced to less than 10% of atmospheric levels. Laboratory column leach tests that were subjected to oxygen flux rates of 10 % showed reducing oxygen ingress into acid-forming material can result in significant acid load reductions.   The oxygen content below the cement kiln dust cover was generally lower than 5% and water quality measured in lysimeters beneath this cover improved after 50 weeks of emplacement. Column leach tests containing saturated samples were undertaken to determine the most appropriate water medium in preventing pyrite oxidation. The sample saturated with ARD (pH ~ 3) had a negligible acid production rate and leached very minor Al concentrations although Al is soluble at low pH. This indicated saturating waste rock dumps with ARD can be an effective method in mitigating ARD formation.

Jan 1, 2007

By M McLean

This paper deals with change strategies on brownfield and greenfield sites in extractive industries. It draws upon contemporary experiences across Australian, Indonesia and Papua New Guinea (PNG). Change strategies can be used when owners of an extractive industry operation want to optimise their resource. This paper draws upon many tried and proven theories and practices, including the findings of the Tavistock Institute (Trist, Emmery, Bamford, Jaques), as well as the concepts of Adult Learning espoused by Malcolm Knowles and is supported by learnings of Australian based management consultants. This paper reviews a range of approaches that have succeeded in the integration of systems, machines and people, with the key corporate objectives of: increasing productivity; decreasing cost; improving on-time delivery performance and achieving long-term survival. Such integration needs to be measured to show the outcomes from the change strategies and the authors have worked within many measurement regimes and metrics but for the most part, found that JaquesÆ set of metrics being æquality, quantity, resources and timeÆ has gained currency across many Australian operations. This paper contends that investing money in machines alone without a commensurate investment into the people side is counter-productive. Further, if there is not an understanding of processes, ie stable and capable, core and support processes, then all that new technologies will do, is to make what is done badly, only quicker. Recent interventions for the most part, have been cognisant of this balanced approach towards change management. The change strategies described are across extractive industry implementations, using a number of tools and techniques drawn from Continuous Improvement and Six SigmaÖ (registered trade and service mark of Motorola Corporation, USA).

Jan 1, 2006