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By J Player

Big Bell Mine started experiencing relatively large mining related seismic events, and accompanying rockbursts, from February 1999. Twelve rockbursts damaged access development from February 1999 to June 2000, with severe damage extending for up to 100 m along footwall drives. Five seismic events associated with the rockbursts were recorded by the AGSO, measuring 1.9, 2.2, 1.7, 2.4 and 2.2 on the Richter scale. These events affected 485 and 460 footwall drives in August and November 1999 and 535 footwall drive in June 2000 (drive level nomenclature is equivalent to the depth below surface and RL). After the third event (July 1999) it was apparent that the seismicity was not a once-off phenomenon. This (sudden) onset of seismicity required management to implement a series of precautionary measures:to ensure the safety of the workforce, to maintain continuity of production, and to reduce rockburst damage rehabilitation. The measures included extended re-entry periods and exclusion zones in high-risk areas, improved rockburst resistant support systems in areas prone to damaging seismic activity and improved support systems in areas prone to shakedown damage. A full-scale minewide ISS seismic system was ordered in October 1999 and commissioned in February 2000. A portable eight-channel CSIR-Miningtek system was installed at short notice as an interim measure in August 1999. This CSIR system covered the northern producing stopes, where the majority of the rockbursts had occurred. The objective of the seismic monitoring was to monitor relative activity and to determine trends with regards to time and location. MAP3D numerical modelling was used to investigate the relationship between seismicity and various combinations of stress components to assess the relative seismic risk in both current and proposed working areas. This information is used to determine where and at what stage in the mining cycle the rockburst resistant support is required. Analysis of the seismicity has determined two distinct modes of seismicity û small-scale localised, high frequency events in high stress areas and larger events related to shear along previously intact foliation surfaces. This paper includes a summary of the seismic history, seismic data analysis, support system design, mine design adjustments and management action to minimise the effects of seismic activity at Big Bell Mine.

Jan 1, 2000

By G Brewster

The Eagle on the Hill tunnels form part of an upgrade of Mt Barker Road, 15 km to the southeast of Adelaide. The upgrade significantly improves safety and reduces delays on this major road, which winds steeply through mountainous terrain. The twin tunnels each spanning 15 metres run in parallel for a length of 480 metres. The tunnels are excavated in slightly weathered high strength slates and very high strength quartzites of the Saddleworth Formation on the western margin of the Mount Lofty Ranges. Steeply dipping slate cleavages and the high fracture ratio result in many slope stability problems in the project area. The level of geotechnical investigation undertaken prior to the calling of tenders for the project was extensive. This included the excavation of a pilot tunnel along one of the tunnel alignments, which allowed accurate mapping and rating of the rock, resulting in an increased level of confidence during the tender process. One of the features of the winning alternative tender design was the use of canopy tubes, flexible steel ribs and shotcrete to replace up to 40 metres of deep portal cuts in unstable rock with driven tunnels. Slope stability issues were overcome with the use of rock dowels and shotcrete. The support concept allowed the safe driving of the tunnel portals with as little as two metres of overburden. The design incorporated lining drainage and criteria for fireproofing based on European experience to ensure the ability of the tunnels to remain stable in the case of a severe fire incident. The support design allowed for maximum flexibility with a range of support types able to deal with the varying ground conditions. Design development and support refinement continued throughout the tunnel construction phase with close liaison between the designer and the constructor. Monitoring and review of feedback from the construction site by the Sydney based design team was easily achieved by means of electronic transfer of photographic and survey information, telephone and fax communication and regular site visits. The contractor for this project is Macmahon Concrete Constructions Joint Venture (MCCJV) and the designer is Connell Wagner. Excavation commenced in January 1998 with tunnel breakthrough having been achieved in early-August 1998 and mid-September 1998 respectively. Concrete lining construction is scheduled for completion in April 1999.

Jan 1, 1999

By T Hayward, G Lane, M Phillips

In December 2004 Phu Bia Mining Ltd commissioned Ausenco International Limited to conduct a feasibility study for its Phu Kham copper-gold project located in Laos. The feasibility study for a mining and processing operation treating 12 Mtpa of ore averaging 0.56 per cent copper and 0.25 g/t gold to produce an anticipated annual average 200 000 t of concentrate containing 25 per cent copper was completed in early 2006. The plant design incorporates a single processing line and includes a gyratory crusher, overland conveyor, coarse ore stockpile, SAG and ball mill grinding circuit, flotation circuit including regrind and three stages of cleaning, concentrate dewatering and concentrate load-out facilities. The Phu Kham copper-gold mineralisation comprises two principal styles: stockwork-disseminated and banded-massive sulfide within skarn limits. Primary copper in both mineralisation styles occurs as chalcopyrite and secondary copper sulfide minerals. Skarn includes the copper and gold mineralisation contained in pyrite, silicate, magnetite and haematite skarns, and in quartz-pyrite altered sediments. Both the stockwork-disseminated and banded-massive sulfide ores contain relatively high proportions of pyrite relative to the copper and gold mineralisation. Thus, the flotation metallurgy of the Phu Kham orebody is characterised by the need to reject a high proportion of the pyrite during differential flotation to yield a concentrate grade of approximately 25 per cent copper. The rejection of pyrite is accompanied by the rejection of some copper and gold and can result in modest metallurgical recovery. Consequently, the greater the pyrite content, the lower the expected copper and gold recoveries. The relative pyrite content is expressed on the basis of sulfur:copper ratio. For Phu Kham ores, the sulfur:copper ratios are in the range eight to 14 on a blended annual basis, but can be greater than 20 in the skarn components. Higher grades of copper and gold are also present in the skarn mineralisation. The design concepts for the concentrator were influenced by the need to provide a low capital cost approach for the project due to the relatively low grade of the ore and the modest metallurgical recovery. The concepts used to minimise capital cost whilst retaining operating and maintenance flexibility are discussed, together with the metallurgical challenges imposed by the high pyrite mineralisation.

Jan 1, 2007

Bacteria can play a key role in the processing of 'difficult' ores. Bioleaching opens the way to potentially extract copper from vast amounts of otherwise hard to process refractory low-grade chalcopyrite. In my talk I will outline our research philosophy to develop bioleaching as a Precision Processing unit process step. In our view, Precision Processing is a sophisticated approach to mineral processing where the ultimate goal is to measure and characterise the ore body in-ground and in real time during mining, allowing the down-stream unit processes (bioleaching, in this case) to be continuously tailored and tuned via feedback and feed-forward controls to obtain the highest possible recoveries at the lowest possible cost and environmental impact. I will describe some of the work that we are undertaking to better understand the interfacial phenomena underlying the fundamental bioleaching process with the aim of coming to a Precision Processing approach. We use techniques such as interfacial electrochemistry (scanning electrochemical microscopy, SECM), AFM, zeta potential measurement, and synchrotron science to elucidate the parameters that drive bacterial selectivity and adhesion, bacterial metabolism, and dissolution and precipitation processes for model systems and real chalcopyrite ores. As examples of our research, I will discuss in some detail our method to produce and characterise micro-patterned CuxS - silica thin films as model substrates for electrochemical and bacterial adhesion work and our approach to the interfacial chemical characterisation of extracellular polymeric substances of bio-active bacterial cells. I will also cover some of our recent findings relating to measurement and interpretation of bacterial adhesion on sulfidic substrates and its implications for bacterial adhesion and substrate selectivity. After having identified and discussed crucial leaching parameters, such as pH, Eh, T, [Cu2+], and [O2], the talk will go on addressing some of the early achievements and challenges encountered in our work to design and prepare low-cost, rugged sensing devices that allow the in-situ (in this case, in-dump or in-heap) localised measurement of these parameters. I will conclude my talk by painting the picture of how the work of our group might contribute to realising the dream of transforming bioleaching into genuine high-tech Precision Processing of minerals. This is an ABSTRACT ONLY. A full-length paper was not prepared for this presentation.

Sep 13, 2010

By Brook W. H

The history of the reduction of iron from its ores is lost in antiquity. Archreologists state that man has practised it for over four thousand years. Until comparatively recent times charcoal was the principal reducing agent for making metallic iron from its various oxidised ores. Coke was first used by iron founders in England in 1619, and its use spread gradually throughout the civilised world from then onwards. Indeed, the destruction of forests to obtain the requisite charcoal made the iron founders, both in England and America, extremely unpopular, and this hampered the iron industry to a considerable extent, until coal provided the metallurgist with a new and better fuel--coke which is used by most pyro-metallurgists today. The transition from wood to coal products for iron smelting had a profound effect on the location of iron works. Particularly was this the case in America where, in the infancy of the industry, practically each of the early States had its own iron producers, but as coal and coke replaced charcoal, there came about a concentration of the iron and steel industry around the coking coal deposits, and so today there are huge steel plants clustered around the soft coal basins in Pennsylvania and Illinois.The development of the iron and steel industry in Australia, which is comparatively recent by world standards, has been cradled in the coal basins of New South Wales. The first steel works of any consequence in this country were built near Lithgow, close by the mines which produced the coal for coking.Incidentally, these works were rather unique in that the three essential materials for iron and steel manufacture-ore, coal, and limestone-were found virtually at the works' back door.When, in 1912, the location of the proposed steel works for The Broken Hill Pty. Co. Ltd. for smelting ore from Iron Knob in South Australia was considered, the site ultimately chosen was at Newcastle, almost on top of seams of satisfactory coking coal. One of the major factors which had determined the site of the steel works was the fact that, about 1912, three tons of coal were required to produce one ton of finished steel product, and the relative economics of ore and coal haulage were much in favour of bringing ore to the coal.

Jan 1, 1947

Dr Wark said: I have not come to Broken Hill to tell you how to conduct flotation operations; indeed, during my short stay here I have already learned much concerning the process, of the many difficulties which have been overcome, and of those still awaiting solution. My purpose tonight is rather different. All who have been concerned with the operation of the flotation process must have wondered, like myself, why the process is possible at all. In particular, why can minerals which are heavier than water be made to l10at to its surface; why do certain minerals float while others do not; and what are the functions of the added chemicals?I have been asked to describe tonight some of the ways which have been adopted in the Melbourne University laboratory in an endeavour to find answers to these. questions. Knowing that you are just as interested in them as we are and, furthermore, appreciating that were it not for the co-operation of the Broken Hill companies our researches would not have been possible, I regard it as a high privilege that I should have been invited to tell you of our work. Before doing so, I would like to tell you the reasons why the work was started and for whom it has been carried out. Soon after the flotation process had been successfully exploited on a commercial scale a number of investigators sought to determine the theoretical basis upon which it rests, and our knowledge of the function of the added chemicals has been considerably broadened by the published accounts of many workers, particularly in recent years of those working in American universities.The Australian metallurgist played, as you know, a part second to none in the early development of the process, and Australia's mining fields had already reaped such rich rewards from it that, late in 1929, it was felt by some of the leaders of the industry that we should take a larger part in the efforts being made to extend the knowledge of the principles upon which the process is based.Accordingly, several companies - the Broken Hill South, the North Broken Hill, The Zinc Corporation, the Electrolytic Zinc and the Mount Lyell Companies - established a laboratory in the chemistry department of the University of Melbourne for the purpose of investigating the principles underlying flotation.Subsequently another British company, the Burma Corporation Ltd, expressed a desire to co-operate.

Jan 1, 1994

By Butt C. R M

Resurgence in Au exploration during the past decade has been characterised by a considerable emphasis and dependence on geochemical procedures. This has been made possible, firstly, by marked improvements in analytical sensitivity over those previously available and secondly, of particular importance to exploration in Australia, by a better understanding of the distribution of Au in the regolith, which has led to the optimisation of sample media. These developments have given exploration companies the ability to seek and detect subtle and widespread geochemical signatures of concealed Au mineralisation and provided an enhanced capability to interpret the data. As a consequence, several new discoveries have been made, even in areas that have been intensively explored in the past. In the deeply weathered Yilgarn Craton (WA), and in equivalent areas elsewhere in Australia and overseas, Au has accumulated in the upper lateritic gravels and duricrusts of the regolith, probably during humid climatic periods in the Tertiary. The laterites may not only be Au ores in themselves, but research by CSIRO and CRC LEME has shown them to be very important sample media, (eg Anand and Smith, 1992). In many areas, however, the laterite has been eroded and hence is unavailable as a sample medium and chemical modification under more and conditions since the Tertiary has leached Au from the upper saprolite. This has greatly increased the difficulties of exploration, particularly where reliance was placed on sampling between 2 and 15 m of the surface. Further research, however, has demonstrated that, despite this leaching, recent remobilisation of An has caused it to concentrate in a specific soil component, pedogenic carbonate, usually in the top I - 2 m, thereby giving surface expression even to mineralisation that is concealed by over 20 in of leached overburden. Secondary carbonates, commonly referred to as calcrete, may precipitate as calcite and/or dolomite in regoliths where the average annual rainfall is less than about 600 mm. Pedogenic carbonates are those that form in unsaturated (vadose) soil horizons. They are widely distributed in the Gawler and Yilgarn Cratons. In the Yilgarn Craton south of about 30¦S ('the Menzies Line'), they are seemingly more abundant over more basic rocks and towards the south east (Figure 1). In contrast, groundwater calcretes form in saturated (phreatic) environments, typically in the axes of major drainages north of the Menzies Line. These are known to accumulate economically-significant grades of U but not, apparently, An.

Jan 1, 1997

By G Solly, P J. Leevers

Day-to-day operating practices at existing operations need provide high quality data for decisions that will impact directly on the potential value of the available resource, in addition to meeting standards of quality expected of data used in feasibility studies that will be completed to obtain additional capital required to finance operational improvements. Drill hole location, down hole survey and assay data standards of accuracy and precision have received considerable attention in recent years. The authors propose that geological descriptions of both cored and non-cored drilling warrant at least equal attention, considering their fundamental role in establishing the framework used for geological modeling and resource estimation. The iron ore deposits of the Middleback Ranges have been a major source of iron ore for almost a century. High-grade hematite-dominant ore is currently mined by OneSteel from three open pit operations supplying ore to the companyÆs integrated steelworks at Whyalla. A review of OneSteelÆs future iron ore resources, commenced in 2002, highlighted the need for more flexible and comprehensive management of all forms of geological data used in resource evaluation. Driving this program was the information needs of feasibility studies of the Iron Magnet deposit, located beneath the existing Iron Duke and Iron Duchess mines. Prior to the beginning of 2003, resource evaluation drilling data collected by OneSteel was managed using an in-house system based on industry standard relational database software. The system was demonstrably effective in ensuring the fundamental integrity of basic drilling data, but lacked necessary capabilities for the acquisition and management of geological descriptions, geotechnical and geophysical data obtained by down-hole logging. OneSteelÆs existing system for the management and interpretation of geological descriptions was restricted to storage of a single three digit code for each lithological description interval. The original logs for a large number of older drill holes could not be located, having been either poorly archived or culled from the database in the belief that they did not contribute to the understanding of the resources currently being mined. The three digit codes represented a combination of lithological and stratigraphic descriptions, including many subtle variations in iron ore colour and texture believed to be associated with variations in geochemistry, but subsequently demonstrated to be either incorrect or inconsistently applied. This resulted in the establishment of a plethora of codes for a relatively small number of distinct lithologies. Improvements implemented by OneSteel geologists addressed these shortcomings by ensuring the new data management system: facilitated the objective description of lithological characteristics; distinguished between obsevations and interpretations (eg lithology versus stratigraphy); promoted consistency between descriptions provided by different geologists; and helped to ensure data integrity by developing an audit trail for alterations made to data subsequent to its acquisition. The data used to develop interpretations of mineralisation distribution and characteristics are fundamental to the effective utilisation of a mineral resource: any mineÆs most important asset. Resource related risk is widely recognised as the principal source of technical risks affecting resource development projects, whether they are new mines or expansions of existing operations. A key lesson from this work is that most commercial or æin-houseÆ developed geological data management systems are able to handle basic data validation tasks effectively. Geologists, however, need to ensure that the data management system is appropriately structured to help promote the acquisition of objective and consistent data for interpretation.

Jan 1, 2003

By T F. Guerin

Explorationn and mining have shown to cause significant impacts to the terrestrial and marine environment. Current mining and exploration techniques are outlined in the light of their potential to impact upon the environment, ie negligibly, negatively or positively. A profile of five Australian-based gold producers is presented. The development of protocols to specifically deal with the highly regulated and ever changing, mining and environmental legislation. demonstrates mining companies can successfully opcrationalise the concept of sustainable development.

Jan 1, 1992

By R G. Richards

Although most New Zealand coals are low in ash, there are situations where high ash coals could be won. Not all high ash coals can be upgraded by physical means, since the ash is either inherent in the coal or bound in such a way to make its physical removal either impractical or uneconomic. Nevertheless, the authors believe, the situations where high amounts of ash can be economically removed by physical means to make a saleable product are considerable.

Jan 1, 1979

In the last two years the Commission for the Environment has received four Environmental Impact Reports (EIR) for Audit and has been or is involved with at least four environmental impact assessments (EIA) related to mining. The EIRs have included Weavers Coal Mine, the Monowai-Maratoto mining proposal, the Martha Hill mine and the Wainui Road Mill. The EIAs are related mainly to coal fields in the Waikato but also included a further EIA on Martha Hill.

Jan 1, 1986

By Armoo K, Tran T

Cementation has been widely used in several hydrometallurgical processes for recovering gold and silver from process liquors. The process is electrochemical in nature, in which gold and silver are precipitated from the solution using less noble metals such as zinc, iron and copper. This paper summarises the current practice of gold cementation from cyanide liquors using zinc powder. Various developmental studies on the cementation of gold and silver from various systems (chloride and bromide) are also reported.

Jan 1, 1991

By P A. Montoya

La Colosa is a world-class porphyry Au project located in Colombia, currently undergoing prefeasibility analysis. As part of collaboration between AngloGold Ashanti and the AMIRA P843A GeMIII Project, the application of emerging geometallurgical characterisation testing and modelling tools has been incorporated in early stages of project development. The aim of the geometallurgical study is to map inherent comminution variability across the La Colosa deposit providing information critical for mine/mill design and optimisation. In this study, site-based data incorporating multi-element assays, quantitative analyse X-ray difraction QXRD bulk mineralogy measurements, EQUOtip rebound hardness data, and routine geological logging information from 59 diamond drill holes has been integrated with a range of geometallurgically specific comminution test (ie GeMCi, A × b, BMWi). The work in this paper demonstrates the integration techniques used at La Colosa to link routine data acquisition methods with comminution test results through the development of proxy support models. The integration incorporates a range of statistical techniques including principal component analysis and regression modelling. By creating proxy models, comminution index estimates can be propagated into the geological database enabling comminution processing domains to be defined. These domains provide the first spatial representation of comminution performance and variability at La Colosa and can be compared against traditional geological domains. This study provides the foundation for ongoing comminution characterisation as the La Colosa project evolves through project cycles into an operational mine.

Sep 5, 2011

By M Paine

Work to date has shown that the use of Al2O3:SiO2 ratios is suitable for identifying potential gibbsite bearing samples. Subsequent confirmatory XRD analysis helps to refi ne this initial identification. Based on these methods, gibbsite has been mapped in two common settings:1. along steeply dipping faults, or2. in association with stratigraphic contacts where one unit is aluminous (eg dolerite dyke).On a microscale, the samples studied illustrate an association between haematite, and to a lesser extent goethite, and gibbsite. In these samples the dominant forms of haematite are discrete crystalline phases of either microplaty haematite or euhedral martite. Two dominant forms of gibbsite were observed:1. vein style gibbsite that cross-cuts (or infill’s cracks) in goethite ± martite iron oxide associations, or2. gibbsite intimately intergrown with and forming a matrix to microplaty haematite.Some of the gibbsite microstructures observed suggest that it may have formed during a very hydrous, possibly hypogene, stage of the deposit genesis. The presence of this crystalline gibbsite, and in particular its occasionally euhedral form, suggests that aluminium was at some stage remobilised, at least locally, and then precipitated from solution as gibbsite. These observations suggest that these has been a phase of gibbsite precipitation that may have had a close but complex relationship with regards to the timing of the mineralisation processes, rather than formation as a result of late stage lateritic weathering.

Jul 11, 2011

By V A. Chanturia, T N. Matveeva, V V. Getman, A Yu Karkeshkina

The development and application of new effective environmentally friendly reagents for the flotation of thin and ultrathin mineral components is an urgent task. The analysis of the nomenclature of chemicals, including flotation reagents and flocculants, showed that water-soluble polymers (WSP) might be used in flotation separation of fine grinding products containing non-ferrous and precious metals. Water-soluble polymers that are responsive to temperature changes are the most attractive as reagents during flotation. These are the thermo-responsive polymers or thermomorphic polymers. The presence of nitrogen and oxygen atoms in the polymer molecule contributes to the formation of a coordination bond with non-ferrous and precious metals. A research conducted at the ICEMR RAS within the framework of the scientific school of Academician of the Russian Academy of Sciences Chanturia helped to develop a method of flotation of finely ground mineral particles containing valuable components using modified thermomorphic polymers. The paper focuses on the experimental study of poly (vinyl caprolactam) (PVC) as a flotation reagent for gold recovery from finely ground mineral products. PVC is a ready-made water-soluble thermosensitive polymer that does not require complex synthesis. PVC has a high ability to form complexes in an aqueous environment when heated. According to experimental data, the polymer interacts with gold nanoparticles, contributing to the extraction of gold from fine mineral products and the tailings that makes it perspective as an additional flotation agent for the processing of gold-containing ores.

Aug 24, 2022

By C E. J de Ronde, I C. Wright

Oceanic subduction-related volcanic frontal arcs extend over 20 000 km within the western Pacific basin and over 21 500 km worldwide, yet they remain largely unexplored with respect to active seafloor mineralization. Systematic exploration of 26 major submarine volcanoes along ~840 km of the Kermadec arc northeast of New Zealand has documented ten (39 per cent) as being hydrothermally active. This frequency of venting is comparable to that on slow-to-moderate rate spreading mid-ocean ridges, which comprise ~80 per cent of the 60 000 km-long global system of spreading centers. The chemistry of fluids discharged from the Kermadec arc volcanoes is moderated by magmatic components in both the gaseous (CO2 + SO2-H2S) and liquid (Fe) phases at very high concentration.The high frequency of venting coupled with chemically rich discharge discovered during this first systematic survey of any arc system forecasts submarine arcs as being important sources of chemicals to the oceans and as potentially lucrative exploration sites for seafloor mineralization. The exploration protocols developed during these surveys include bathymetric mapping of mostly unknown volcanic edifices, followed by detailed water column profiling and sampling to detect and characterize volcanic fluid emission signatures. These procedures are being refined as the survey progresses, both for efficiency and as direct seafloor observations become available for predictive application of water column plume information to guide seafloor mineral exploration.

Jan 1, 2002

By S L. Birch, M D. Raven

X-ray diffraction (XRD) is a well-recognised, invaluable tool to provide detailed mineralogical analysis on a wide range of applications. However, despite the wide use of XRD in many industries, there are currently few recognised standard methods for quantitative XRD analysis and none for the analysis of iron ore materials. An initial step towards preparing a standard method for XRD analysis of iron ores was to assess the current level of precision achievable by practitioners of the technique by organising an international round robin. Six Australian chemically certified iron ore reference materials were distributed to over 100 international participants. A summary of over 120 data sets from more than 80 participants is presented. Results show that a bewildering array of techniques for sample preparation, data collection, phase identification and quantification were used. The reported values for the main components (ie hematite, goethite, quartz and amorphous content) show not only extensive variability between participants but also within participants’ results for those who submitted multiple data sets. The disappointing low level of precision exhibited for a relatively simple mineral phase system indicates a strong requirement for development of a standardised procedure.CITATION:Raven, M D and Birch, S L, 2017. Summary of results of an international X-ray diffraction round robin for mineralogical analysis of iron ores, in Proceedings Iron Ore 2017, pp 599–604 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By P Mulvey

"Currently mine process studies and geochemical waste characterisation are considered as two interdependent studies, necessary for the development of the mine and inclusion in the environmental impact statement (EIS). Geochemical waste characterisation will utilise the simulated tailings produced by the mine process studies team to understand the behaviour of the tailings, but the two teams rarely integrate these to develop a coherent and agreed final design.Thorough mine waste geochemical assessments can develop processes to minimise environmental harm, resulting in substantial savings in the decommissioning, closure and rehabilitation phases, and may also be able to address changes in mineral processing methods that can result in substantial savings in process inputs, or even recovery of metal concentrates.Based on geochemical waste characterisation, the full cost of waste management can be calculated and incorporated into the costing of milling.  This allows for a more effective evaluation of the metallurgy.  A number of examples are presented in which substantial improvements have been made from the collaboration of both the metallurgical and geochemical teams during planning and the metallurgical team and environmental team during operations.*This paper is only available for individual download. It is not included in the conference proceedings*CITATION:Mulvey, P, 2013. Optimising metallurgy at the planning stage to minimise environmental impact - a feedback loop from geochemical waste characterisation, presented to MetPlant 2013 Conference (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

By M Alston

Organisations’ incident classification processes are plagued by the overclassification of events, often leading to excessive workloads and suboptimal outcomes. This presentation addresses the pressing need to rethink how incidents are classified to maximise organisational learning and minimise systemic risk. A major issue in the current incident classification landscape is the tendency to classify events at high levels, overwhelming organisations with investigations they cannot efficiently handle. This results in inadequate risk reduction and learning opportunities. The link between injury classification and investigation methods further compounds these problems, creating unnecessary administrative clutter. Challenging the misconception that every event, no matter how minor, requires a comprehensive investigation, this presentation advocates for a shift in perspective. The key recommendation is to decouple injury classification and risk matrices from the decision-making process regarding what and how to investigate. Instead, the emphasis should be placed on identifying opportunities for organisational learning and risk reduction. Organisations can streamline their incident management processes by adopting a more pragmatic approach that aligns incident classification with the organisation’s investigation capacity. This transformation focuses on achieving meaningful outcomes, enhancing safety and improving performance. This presentation provides an innovative process for organisations to revamp their incident classification practices, enabling them to harness the full potential of incident data for learning and risk mitigation. It highlights the importance of aligning incident classification with the opportunity for organisational learning, ultimately leading to more effective incident management and enhanced safety outcomes.

Apr 16, 2024

By C Placzek, E Beattie, K Blake

Channel iron deposits (CID) consist of ferruginous chemical sediments, and are an unusual subset of Phanerozoic ooidal ironstone deposits almost unique to the Pilbara, where they constitute around 19 per cent of the Pilbara’s iron ore exports. These deposits occupy many of the ancestral river channels of the Pilbara region, especially the Robe River palaeochannels, incising and meandering through the Precambrian banded iron formations (BIF) of the Hamersley Group and the underlying Fortescue Volcanics.This paper explores the factors underlying geochemical variation in CID, particularly the chemical properties of goethite. The selected deposits in the western Robe palaeochannel and its tributaries show little or no secondary reworking by later water tables. There is a total absence of aluminosilicate clays with all the deleterious elements such as aluminium and silica. Instead, these are associated with the goethite mineral lattice, either within or adsorbed to the cortices of pelletoids.A thickly vegetated environment, and the presence of the Maddina Volcanics as potential source rocks for these western Robe CID is offered as an explanation for relatively high aluminium in the deposits studied, and, in turn, as the reason most parts of the palaeochannel are preserved as inverted topography.CITATION:Beattie, E, Placzek, C and Blake, K, 2017. Dirty goethite – a geochemical characterisation of some western Robe River channel iron deposits, in Proceedings Iron Ore 2017, pp 489–502 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017