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In the mid-1990s, after a long period of antipathy between the company and its detractors, Rio Tinto embarked upon an ambitious cultural change program that sought to transform the fundamental basis of its relationship with global, national and local stakeholders. This has evolved into a broader pursuit of positive cultural change within Rio Tinto as part of the mining industryÆs Sustainable Development initiative. Initially driven from the top down, the communities component of this program comprises an architecture of policies, value statements, social research and verification systems. The commitment to better community relationships is best exemplified in Australia by the scope and scale of the GroupÆs Aboriginal land access agreements, community development programs and the work of the Rio Tinto Aboriginal Foundation. While collectively these form the core elements of an evolving set of internal social competencies, development of second-tier competencies is required to organically embed a culture of sustainable relationships with local and regional communities. Second-tier competencies will include appreciation of social dynamics, social science and diversity at middle management level; rigorous social research that properly informs development options for companies and host communities; career paths and recognition within the mining industry for young professionals both generally and from stakeholder communities; proper community-needs assessments, research into such things as purchasing power and other economics data, and inventories of public goods such as land-carrying capacity and water availability. Without this information it is difficult to gain an appreciation of and to alert people to the consequences of change brought on by a mine. The next decade will see second-tier social competencies promoted within successful mining companies. Measures to achieve this include a range of Human Resource (HR) incentives such as recruitment and career advancement based on broad competencies rather than narrow technical proficiency, humanities training for mining professionals and performance rewards that recognise social competence. A sustainable future for mining in a globally connected social landscape requires selection of people who can listen, relate and act in an open social system. The challenge for the mining industry, its professional organisations and educational institutions is to acknowledge this and develop these new aspects of mining industry professionalism. This cannot be left to individual companies if the industry is to have a sustainable future.

Jan 1, 2002

By Koeng R, Richardson M, Hoare R

A discrete event computer simulation model was developed for two of the stoping methods currently used at the Z.C. Mines Broken Hill oper- ations. The objective in undertaking this project was to provide an effective tool for mine planning and design to allow comparisons of alternative extraction strategies and attempt to optimise the allocation of capital equipment and human resources. The Slam II simulation program was used in conjunction with ,a com- monly used data editor, text editor and graphics package to allow the simulation to be done on a personal computer with minimum training requirements. The computer hardware used was a portable computer cur- rently available using 80386/20MHz electronics. Specific logic techniques were developed to allow the Slam II language to simulate mining opera- tions because it was originally developed for manufacturing and com- mercial simulations. The design of the model was based on observations and a data collec- tion campaign. The model was designed with flexibility which allows simple editing of the input data which includes: - Insitu volumes - Development statistics -Loadout efficiencies -Loader speeds, availabilities and capacities -Chute numbers, volumes, distances and blockage statistics -Trucking statistics -Work schedules -Utility statistics

Jan 1, 1988

Solid Energy New Zealand (SENZ) uses a 20+ year period for integrated planning of all its business activities. It has an ongoing program of coal resource assessment to optimise future mines within this 20 year period, using a six step resource and mine planning process. Desktop review and conceptual study at preliminary Levels 1 and 2 are based on general coal resource information. Further coal resource investigations are carried out for the more detailed evaluations in secondary assessment, prefeasibility study, feasibility study and detailed engineering from Levels 3 to 6. At Levels 1 and 2, completing conceptual planning, including preliminary resource evaluation and economic appraisal to the target cost uncertainty level of ¦33 per cent, is challenging in New ZealandÆs highly variable geological and geographical conditions. Where coal deposit geometries are relatively simple, approximate methods for determining pit limits using overburden strip ratios, seam thickness, physical boundaries, and quality cut-offs may be sufficient. Many New Zealand coalfields are however complicated structurally, with multiple seams and extensive folding and faulting. Coal seams are characterised by variable dip, thickness, and quality over relatively short distances. In the North IslandÆs Waikato coalfields, coal is typically overlain by weak sediments and clay rich strata that necessitate very flat cut and fill slope angles. The proximity of these deposits to major infrastructure (including towns, highways and rail lines), significant environmental features such as the Waikato river and lakes, and valuable dairy farmland, add further complexity. Traditional preliminary mine planning techniques applied in these conditions are insufficient. Pit optimisation software, widely used in the metalliferous mining industry since the 1980s, offers the ability to analyse many more specific factors affecting pit limits, mine layouts, and economics, with more rigour and for a much larger number of scenarios, than traditional methods allow. SENZ therefore decided to adapt and use æWhittleÆ pit optimisation software for Level 2 analysis of several Waikato opencast prospects. This paper describes this work.

Jan 1, 2005

By A Patwardhan, M M. Alam, K K. Thatavar

A commercial wet scrubber was used in the SIU-Joy dust control laboratory to test several concepts for improving the dust control efficiency of a wet scrubber. The concepts tested included two filter-two-spray systems, hollow and full-cone sprays, horizontal and vertical sprays, different layer filters and addition of surfactant. The optimised scrubber configuration had water-only vertical sprays for pre-wetting coarse dust, and vertical surfactant-laden water sprays for wetting ultrafine particles. This scrubber configuration reduced dust concentrations from 250 mg/m3 to 1.8 mg/m3. In comparison, the conventional scrubber configuration in the feed provides an outlet dust concentration of 3 - 4 mg/m3 in field operation. Upon successful testing and optimisation of parameters in the laboratory, field demonstration of the concepts was conducted at an Illinois coal mine. The optimised scrubber configuration was tested in the field with good results in terms of improved visibility in the face area and reduced respirable and quartz dust concentrations. Additional modifications in the field involved relocation of the scrubber suction inlets from the bottom to the side and changing the water spray configuration on the miner head. These additional changes were based on a conceptualised spatial dust distribution profile in the face area. The results of these laboratory development and field demonstration studies are presented in this paper.

Jan 1, 2005

The weathering profile, in arid terrains, is commonly capped by different kinds of hardened crust, whose formation is related to recent or former climates. One may distinguish silcretes, calcretes and the ferruginous (or ferro-aluminous) laterites. the present keynote address mostly deals with the lateritic regolith and, moreover, the influence it has on mineral exploration. The lateritic regolith, also called "cuirasse", is a result of a massive accumulation of Fe (and/or Al) oxides on top of weathering profiles developed during former, probably seasonal humid, climatic episodes, and whose preservation depends on the characteristics of later climates. The total thickness of such weathering profiles commonly exceeds 50 m, with an almost complete substitution of the rock forming minerals by secondary minerals as kaolinite and Fe-Al oxi- hydroxides (hematite, goethite, boehmite, gibbsite). Such an alteration of the primary minerals assemblage is of course accompanied by significant changes of the chemical composition, as concerns major and trace elements. The latter are distributed amongst the main secondary mineral phases or trapped in some primary resistant minerals, but may also be leached, totally or partially. Gold is also affected by lateritic weathering, as shown for instance by morphoscopic and geochemical studies of gold grains collected in the different horizons of the profile, which indicates some dissolution followed by reprecipitation.

Jan 1, 1988

By R R. Lovel

In this paper, life cycle assessment methodology has been used to assess the variations in water use associated with different metal production and processing routes and provide insights into the value derived from water usage in the minerals sector. Using water consumption data derived from the literature it has been shown that the æcradle-to-gateÆ water consumption (or embodied water) for production of the various metals considered in the study ranged from 2.9 m3/t for steel up to 252 087 m3/t for gold. The results largely reflect the grade of the initial ore used to produce each metal, and can be approximated by the following equation: W = 167.7 G - 0.9039 where: W = embodied water (m3/t refined metal) G = grade of ore used to produce metal (per cent metal) The study showed that indirect water consumption in the metal production life cycle, in particular that due to electricity generation, can make a significant contribution to the embodied water value, eg aluminium production. When expressed in terms of m3/t ore, the results for all metals considered indicated that the embodied water is roughly, on average, three times the water consumption of the mining and concentration stage. It was also shown that the economic value per m3 of water consumed for the minerals industry exceeds that for the agricultural and industrial sectors, supporting the view that allocating water resources to the minerals industry has a strong underlying economic basis. Water reforms currently taking place in Australia aim to address issues such as competition for water access, reduced security of supply and increase in cost. Consequently the minerals industry, along with others, can be expected to come under increasing pressure to reduce fresh or raw water use and to integrate water use across sectors. While water recycling is an obvious candidate to help reduce water consumption in the minerals industry, issues such as water quality, among others, will influence the extent to which this can be achieved. In addition, wastewater volumes can be minimised using techniques such as pinch analysis to establish and use the minimum water requirement for the process. The use of dry or near-dry processing technologies, for which the demand for water is small or zero, may be a more radical solution to the water consumption problem; however, it is possible that the introduction of dry processing would bring with it a new set of problems, including dust.

Jan 1, 2006

By G Varley

This paper describes the mining methods and strategy used to extract the 5 Orebody crown pillar at the Isa Lead Mine over the past five years. The bulk of the crown pillar was extracted by the use of sublevel open stope method. An uphole bench stope was mined to scavenge the remaining ore. Geomechanical issues associated with the crown pillar extraction are described. Stope sizes were gradually increased on a stope by stope basis. This has allowed the maximising of ore recovery while relevant risks were managed. The principles in designing ore rib pillars against various types of fill materials are also described.

Jan 1, 2002

Modern, research-based approaches to mineral exploration are essential to the future maintenance of the mineral industry. These need to fully utilise the rapidly expanding growth of understanding of the evolution of the earth's crust, and be properly integrated with advances in understanding of chemical and physical processes involved in ore formation. BMR has a major role to play in supporting the growth and utilisation of this research base, as well as maintaining the national geological and geophysical bases which are essential both to tactical and strategic interests of Australia and of its mineral industry. The objective development of data-process modelling is one target of such strategic research based on a more integrated approach to research by BMR, mineral companies, CSIRO and the universities with emphasis given to promoting positive feedback during research activities. Examples of the success of strategic research in Australia and overseas are noted in the Text.

Jan 1, 1986

This research is about human development and socio-economic progress of the main mining areas of Chile in the period 1990 - 2007, and especially about the positive effects that mining activity has on poverty reduction and indicators related to the Millennium Development Goals of the United Nations. The analysis is doubly interesting, if one considers that the economic and social developments in Chile, recognised and prominent among the Latin American economies and developing nations, are more evident in mining areas as Tarapacß and Antofagasta (northern Chile), which concentrated than more 70 per cent of investments and mining assets in the country. Additionally, the study concludes with methodological reflections for the evaluation of socio-economic impact in the mining industry in developing countries.

Jan 1, 2009

By S Hapugoda, J R. Manuel, M J. Peterson, A Poliakov, E Donskoi

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Aug 12, 2013

By Hart A. T, Lanigan P. G

BHP is currently undertaking research into plasma are metallurgical processing at the Central Research Laboratories (CRL), Shortland. The use of high intensity plasma arcs for melting and smelting has a number of advantages, including; the ability to control atmosphere and furnace operating conditions, total enclosure, high temperatures, versatility, and low in-process inventory in a compact system. The intensive conditions, achievable in a plasma furnace system, make it particularly useful for the smelting and melting of difficult-to-treat materials, such as ore and metallic fines and refractory ores. Two transferred arc plasma smelting furnaces have been set up at CRL; a 100kg furnace is used for small scale melting and smelting studies and a 1 tonne furnace for pilot scale plasma processing studies and equipment development. Power is supplied by a 1MW GEC thyristor DC power supply. A 220kW DC power supply is available for "off site" pilot process trials and demonstrations, and a 150kW non-transfered are plasma torch is also available for other studies. The facility has been designed to allow maximum flexibility in researching and developing applications in metallurgical processing and transferring developed technology to company operations. The objectives behind the development of the facility, details of the facility and an outline of current research areas will be Discussed.

Jan 1, 1987

By P Nissen, T Jenke, M Ralph, M Cattani, M Quinlan

The West Australian Government hold an annual ‘Mines Safety Roadshow’ around the State’s regions and the capital city, Perth. Each year presenters provide an update on legislation and safetyrelated themes. A recurring theme is the mining industry fatality rate. Professor Michael Quinlan’s ‘Ten Pathways to Death and Disaster’ (Quinlan, 2014) has been referenced regularly to assist in structuring workshops and conversations concerning fatality prevention in the mining industry. The ‘Ten Pathways’ are the outcome of an analysis of fatal injuries in the mining industry, which identified a series of common themes to the fatalities: Pathway 1: Design, engineering, technical and maintenance flaws. Pathway 2: Prior warnings or causes for alarm ignored. Pathway 3: Failures in risk assessment. Pathway 4: Failures in management systems and hazard management plans. Pathway 5: Failures in auditing. Pathway 6: Economic pressures compromising safety. Pathway 7: Failures in regulatory oversight and inspection. Pathway 8: Worker and others expressing concern prior to the incident. Pathway 9: Poor management – worker communication and trust. Pathway 10: Emergency and rescue resources and procedures. To determine a fatality risk profile we asked participants at the Mines Safety Roadshows to indicate their perception of their employer’s performance in each of the Ten Pathways. We administered the questionnaire at the Mines Safety Roadshows in 2017, 2018, 2019 and 2023. In this paper, we report on the results of the questionnaires, and suggest how organisations can improve their fatality risk score.

Apr 16, 2024

The epithermal silver-gold Red Rock Deposit is hosted in the Late Permian inter- mediate to silicic composition Drake Volcanics of New England, N.S.W. This deposit represents one of the few low sulfur epithermal precious metal systems in eastern Australia, and differ! from epithermal models in that the hydrotherma: system which produced mineralization was active in a shallow water marine environment. The Red Rock Deposit has a resource of 180,000 tonnes of 66g/t Ag and 0.9 g/t Au, and a Ag:Au ratio of 70:1. Mineralization is largely associated with hydrothermal brecciation, and occurs as disseminations, vein stockworks, and struc- turally controlled lodes. Ore minerals comprise acanthite (argentite), electrum, native Ag, Ag- sulfosalts and base metal sulfides, Alteration minerals associated with ore are quartz, cal- cite, adularia, pyrite, illite, illite-mont- morillonite, chlorite and sphene (leucoxene). Illitic and propylitic alteration zones sur- round the hydrothermal breccia. Bulk rock analyses indicate that alteration is character- ized by the addition of Si, K, Fe, Mg and the loss of Na and Ca. Ore was deposited from a boiling fluid in a temperature range of 222- 295¦C, and of 0.5-7 wt. Z NaCl equivalent sal- inity. An upper hydrostatic depth limit of about 800 m is implied for the boiling fluid ii an open vein. Sulfur isotopes indicate a mag- matic sulfur source, and oxygen isotopes imply a predominantly marine ore fluid. Modern analogs of the submarine hydrothermal system that formed the Red Rock Deposit occur in the Taupo Zone, New Zealand, and southern Kyushu, Japan.

Jan 1, 1987

By J C. Small

Time-dependent deformation occurs when geo-materials are under an applied load; this may lead to additional deflection of a tunnel structure and the stress redistribution in the surrounding rock, shotcrete lining and rock bolt support system over time. A better understanding of this creep behaviour can improve the reliability of design, construction and maintenance of tunnels. Hence, the present investigation was carried out on the time-dependent properties of rock, shotcrete and the combined tunnel support system. Tunnels constructed in different ground conditions were modelled. The closure changes of the tunnel with time and the redistribution of stress in the surrounding rock, shotcrete lining and rock bolts due to the creep deformation were analysed. Results of the present analysis were compared with the results from the commercial program ABAQUS.

Jan 1, 2008

By N Kojola, A Vickerfält, J Huss

The possibility of using an acidic autogenous hydrogen direct reduced iron (H-DRI) slag as a basis for vanadium extraction is investigated. For a raw material to be suitable for producing high-quality FeV, the vanadium oxide content should be sufficiently high and the phosphorus oxide content in a tolerable range. Therefore, the feasibility for vanadium extraction relies on fulfilling two demands: the predominate partitioning of phosphorus to the metal and vanadium to the slag. Correspondingly, the behaviours of phosphorus and vanadium in the Al2O3-SiO2-FeOx-VyOz-P2O5-Fe system were studied experimentally. Slag, 10 g, was put in contact with liquid iron, 30 g, for different durations (2–24 hrs) in closed alumina crucibles at 1873 K. The slag composition was varied between 33.1– 49.3 wt per cent Al2O3, 27.1–46.7 wt per cent SiO2, 16.6–30.1 wt per cent FeOx, and 2.5– 8.8 wt per cent V2O3. The equilibrium phosphorus distribution was 0.42, while the vanadium distribution ranged from 7.6 to 43.4, increasing with the Al2O3- and the FeOx-content.

Jun 19, 2024

By Parkes DB

The excavation of sandstone of generally medium strength for the Liverpool Link Line by Dosco Mark 2A Roadheaders has demonstrated the versatility and good performance of road- headers in suitable rock formations. A description is given of the strata traversed by the tunnels together with descriptions of equipment and crews, excavation sequences, operating difficulties and the results achiev- ed. In addition tunnel construction is des- cribed for a difficult section where there was only O.Sm clearance between invert and a four lane vehicular tunnel below, and O.5m clearance between tunnel crown and a century old sewer above.

Jan 1, 1976

The Golden Cross is the first large precious metals mine to be both commissioned and closed in the æmodernÆ era in New Zealand. This paper discusses the life cycle of the Golden Cross mine, with emphasis on the closure process and post closure management.   The closure process has generally been very well managed, and successful, but in spite of that some on-going issues remain unresolved. Nearly nine years after the end of mining the mine owners are still actively managing the site, with no immediate end to that in sight.   The site has been described as atypical, due to the identification of a deep seated landslide below the tailings and waste rock storage facilities. However that should not be given too much emphasis when addressing the overall closure and post-closure management issues, which could well apply to other existing and future mine sites in New Zealand.   The Golden Cross can provide valuable lessons for other miners, and the issues arising at this site should be watched closely by the industry as a whole.

Jan 1, 2006

By Z U Bajwah

During the Palaeoproterozoic, a large number of granitic intrusions were emplaced in the various parts of the Pine Creek Geosyncline (PCG). In the central region, the granitic magmatism is represented either by the coalesced mass, eg the Cullen Batholith, or individual plutons such as the Mount Bundey Granite which together with the Mount Goyder Syenite intrude the metasedimentary strata, causing wide spread contact aureoles. Some of these granitic intrusions are temporally and genetically related to gold (and less commonly base-metals) mineralisation present in the adjacent metasediments. These plutons are characterised by the presence of biotite and homblende which appear late in the paragenetic sequence. Electron microprobe analyses of biotite and homblende show that these minerals are poorly to moderately zoned. Biotites are characterised by a decrease in Fe/(Fe + Mg) ratios when plotted against AIVI. Similarly a modest decrease in Ti from centre to the margins of the biotite crystals has also been observed. Furthermore, an increase in Mg/(Mg + EFe) ratios from centre to the margins as well as in mafic to felsic rocks is also apparent. On the other hand, homblendes from the granitic bodies display less well marked trends and are poorly zoned. However, they show systematic increases in Mg/(Mg + EFe) ratios, and decreases in Fe, Al"' and Fe/(Fe + Mg) ratios, when plotted against Si. Magnetic susceptibility measurements on powdered samples of the plutons give results characterised by high values ranging from 0.8 x 10-4 to 2.0 x 10-3 emu/g which place the granites in magnetite- series field. This indicates that the oxidation state of the magma was high during crystallisation. The range of chemical compositions of the mafic phases indicates a rise in the oxidation state of the magma as it progressively became saturated in H20-volatiles and other metals, not partitioned into the earlier crystallised phases in the final stages of magma consolidation. These variations in chemical compositions also indicate that initially fOz was high and became progressively higher during fractional crystallisation of magmas; this subsequently led to the emanation of hydrothermal fluids responsible for the mineralisation in the adjacent metasediments.

Jan 1, 1994

By M I. Pownceby, N Karimian, J R. Manuel, M J. Peterson

The CSIRO ore classification scheme for Pilbara ores was used as a reference frame to target recognisable ore types/textures with potentially elevated phosphorus content for detailed analysis. Particles of each individual ore texture were separated from a Brockman high-P ore and each class was characterised using methods including XRF, XRD, EPMA and synchrotron-based XAS. Results were then correlated with optical microscopy and hand specimen identification to establish any relevant associated mineralogical phases and/or textures. This represents a more systematic approach to identification of high-P ore components based on particle and goethite type and texture. The information can then provide the basis for more targeted P-removal strategies factoring in the relationship between particle/ore texture and phosphorus deportment

Sep 18, 2023

By Voermans F. M, Hoyle M. W H

The Archean geological sequence in the West Pilbara region (Fig 1), a deformed greenstone volcano-sedimentary succession regionally intruded by layered mafic/ultramafic lopoliths, batholithic granites, granite stocks and transected by swarms of dolerite dykes, has prompted several companies to search for a variety of base metals and and platinoids (Fig 2). In the first instance, detailed aeromagnetic surveying was completed, producing patterns of marked magnetic anomalism which proved substantially successful in the demarcation of areas warranting geological reconnaissance and detailed follow-up. Revelant to this paper were the obvious magnetic features overlying outcropping and buried mafic/ultramafic bodies which ultimately were proven to be host to Ni-Cu sulphides, pgm, Ti, V, Cr and, more recently, Ag and Au mineralisation. Routine stream sediment, soil sampling and ground geophysical techniques of the day appear, in most cases, to have been adequate in the detection of mineralisation, except in the case of Radio Hill massive sulphides where the Turam E.M. (1972) signal essentially failed to detect the blind conductor (Peters, de Angelis 1987).

Jan 1, 1988