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By D J. Brake

The importance of mine ventilation to health and safety in both coal and metalliferous mines has been long recognised. The primary and secondary ventilation systems in most metalliferous mines incur 50 per cent or more of the total mine electrical power consumption and frequently about 10 per cent of total underground mine operating costs. The requirements for ventilation-related horizontal and vertical development, fans and cooling have a significant impact on mine capital costs and also on mine schedules and start-up times and hence cash flows. There are increasing pressures on regulators and miners to reduce airborne contaminants such as diesel particulatematter, nitrogen dioxide and heat (wet bulb temperatures), and significant pressures to reducegreenhouse gases such as fugitive methane emissions from coalmines and the carbon dioxide footprint of both coal and metalliferous mines. Many previously Australian miners are now globaloperators and have extensive overseas mining operations where local ventilation standards and expertise may not be consistent with Australian practices. The role of the site ventilation officer is also changing with strict new requirements for the statutory position being introduced into Queensland metalliferous mines and the potential for this to become more widespread. Recent regulator and parliamentary review committees have identified systematic shortcomings in mine ventilation compliance, and statutory certificates in both Queensland and NSW now require continuing professional development to maintain currency. Public and investor support for mining are also increasingly contingent on safe, healthy and environmentally responsible practices and the standards for these are frequently tightening. Good ventilation design and operating practices that are consistently well executed therefore contribute significantly not only to a safe and healthy mine but also to a productive and cost-effective operation and the ongoing social licence to operate. There are a variety of ways of providing technical design and oversight into a mine’s ventilation systems; this paper explores some current trends in ventilation standards and statutory requirements, as well as ways to support and develop mine ventilation staff for both domestic and international operations and also the emerging senior technical roles of Group/Principal/Corporate mine ventilation engineer.

Oct 12, 2022

Lihir Gold Mine is situated in a dormant volcanic caldera on a small island off PNG. Not æextinctÆ but dormant. Current ground temperatures are up to 150 degrees Celsius with active geysers in the workings of the mine, pools of boiling ground water adjacent to low-grade dumps and hydrogen sulphide gas emissions. It is a unique mining environment by world standards. This paper will deal with the following issues encountered and managed by the operation:blasting in hot and reactive ground; management of sulphide gas emissions; disposal at sea of all mining waste rock; one dear to all Australian minerÆs hearts û dealing with landowner groups; and unusual human resource issues.

Jan 1, 1999

By F Carrick, W A. Ellis, D R. Mulligan, S I. FitzGibbon

"One of the major environmental impacts of mining is the destruction of habitat. The koala (Phascolarctos cinereus) is an iconic Australian marsupial that has been severely affected by land clearing and its decline is continuing. This has placed pressure upon mining companies and government agencies to ensure koalas are managed throughout the life-of-mines - from land clearing through to rehabilitation of post-mining landscapes. This paper reports on the æKoala VentureÆ research partnership between The University of Queensland and Rio Tinto. As part of the Koala Venture program we examined koala use of two types of restored environments: rehabilitated mined land (20 sites) natural regrowth forests (six sites), at Blair Athol Coal Mine in Central Queensland, Australia. Searches for koala scats revealed evidence of koalas in ten per cent of rehabilitated sites (2/20) and 33 per cent of natural regrowth sites (2/6). Two factors were identified as being of greatest importance in facilitating koala recolonisation of restored habitats. Firstly, all recolonised sites were located close to native forest occupied by koalas (mean 135 m ¦ 52). Proximity to source animals is considered crucial to recolonisation of suitably restored habitats. Secondly, three of the four recolonised sites were dominated by koala food trees, most of which were large enough to be utilised by koalas. Availability of suitably abundant food resources is, therefore, also considered crucial. The requirement for these two factors, in combination, is highlighted by the absence of koalas at several sites that contained abundant food trees, but that were distal to areas with source animals, and vice-versa.Our research demonstrates the enormous potential for restoration of wildlife habitat on post-mining lands, even for species with specific requirements such as the koala. Consideration of the ecological requirements of wildlife during rehabilitation planning is critical to enhancing the likelihood of recolonisation.CITATION:FitzGibbon, S I, Ellis, W A, Mulligan, D R and Carrick, F, 2012. Rehabilitating post-mining landscapes for wildlife - A case study from the Koala Venture research program in Central Queensland, in Proceedings Life-of-Mine 2012, pp 319-324 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

The words ""Uncertainty"" and ""Risk"" pervade every discussion about mining exploration and investment. Perhaps these terms are subjectively understood by industry professionals, but objective portrayal of these concepts outside the industry is a woefully undeveloped science. This paper addresses current industry understanding and practice regarding quantitative risk assessment techniques, and provides examples of the application of three of these techniques. Probabilistic techniques for financial risk assessment are valuable adjuncts to conventional financial analysis, and address a range of issues not assessable by any other means. The value of whole-of-project probabilistic risk assessment is currently debatable for decision-making purposes, but is seen as important as a mechanism to focus attention to the critical issues that ultimately impact on project success. The dissection of project capital into risk and non-risk components provides valuable insights into risk characteristics not readily quantifiable in any other way. This technique also provides a framework for more objective ""what if?"" scenario evaluation and for the capital structure of resource projects. Finally, mechanisms for the valuation of undeveloped reserves are examined, and guidelines suggested. The importance of reliability in production cost estimates is highlighted and the impact of early development on reserve valuations is discussed. The importance of economics throughout all stages of the evaluation process is fundamental.

Jan 1, 1994

After considerable input from the mining industry, the Canadian Securities Administrators (CSA) finalised National Instrument 43-101: Standards of Disclosure for Mineral Projects. This Instrument, which became law across Canada on 1 February 2001, applies to all technical public disclosure on mineral projects and requires all technical disclosure to be based on the work of a æqualified personÆ (QP). While the QP is quite similar to the Competent Person in Australia there are important differences when it comes to all disclosure. This paper will summarise the main areas in which the Instrument introduces major changes to Canadian disclosure standards on mineral projects including the role and responsibility of the qualified person; the increased requirements to file technical reports; the incorporation by reference of the October 2000 CIM definitions of resources and reserves and additional rules governing written disclosure of scientific and technical information. In October 2001, eight months after the implementation of NI 43-101, the CSA compiled a list of frequently asked questions (FAQs) and CSA responses to assist mining industry participants and their advisors in understanding and applying NI-43-101. This document has been well received by industry. The CSA plans to update the FAQs when further guidance is requested. Two industry committees have been established to provide the CSA with technical advice on the application of NI 43-101. As recommended by the Ontario Securities Commission/Toronto Stock Exchange Mining Standards Task Force, the CSA has established an external industry advisory committee û the Mining Technical Advisory and Monitoring Committee (MTAMC) û to monitor the application of NI 43-101 and advise the CSA on industry and professional developments. The role of the CSA-Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Working Committee on Reserves and Resources is to ensure that the future changes and updates to the CIM Standards can be efficiently and effectively incorporated in NI 43-101. During this first year, the Canadian securities regulators have seen an improvement in the quality of disclosure on mineral projects, which will increase investor confidence in the industry.

Jan 1, 2002

By M T. Grigoleit, M S. Schneider

The iron ore industry in Australia has, in recent years, experienced an unprecedented growth phase. But now that major expansions are moving into the operation phase, new challenges have emerged. Whereas initial planning may involve a few modelling studies, ongoing performance monitoring and improvement requires a different, more intense approach. This is especially important in the face of changing factors such as commodity prices, exchange rates and labour markets. Response time is key. As a mining operation proceeds from initial planning to daily operations, the time window for analysis shortens, going from months to weeks to days as the business matures.Simulation models and analysis tools are typically built and run by specialists in the planning phase, but then what? The investment has been made, but realised only once. What if further analysis could be carried out in-house, re-using existing models using up-to-the-minute data? Can we create virtual mines that run in parallel to live operations that allow computers to identify areas of a value creation or operational improvement? These questions can be answered by the innovative application of big data, simulation and predictive analytics. The future will be having this all integrated into one platform that offers, for the first time, an opportunity for non-experts to apply existing modelling and analysis assets – combined with live data – to deliver support for continuous improvement, and the ability to respond quickly to external changes in the best possible way, before they become big problems. These techniques will represent a step change in the ability for operations to maximise efficiency and will underpin the intelligent operations of the future. These issues are addressed in this paper.CITATION:Schneider, M S and Grigoleit, M T, 2015. Maximising productivity through big data, simulation and predictive analytics, in Proceedings Iron Ore 2015, pp 475–480 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

A study was conducted to evaluate the effectiveness of the three types of sample grinders routinely used in the mining industry for the sample preparation of gold ores with particular emphasis placed on testing their capacity to produce a representative assay sample of coarse gold ores. The grinders used in this study are the Labtechnics LM5, the Mixermill 4010 ringmill and the Keegor vertical spindle pulveriser, commonly called a Keegormill. The study was based on the preparation of samples from two sources of known coarse gold ore, the Union Reefs Gold Mine and the Brocks Creek Gold Mine in the Pine Creek region of the Northern Territory of Australia, and a fine gold ore which was from the Macraes Gold Mine in New Zealand. The Union Reefs Mine contains visible coarse gold with 30 per cent to 40 per cent of the gold in the plus 75 μm fraction of milled ore. Discreet particles up to 5 mm have been recorded, Hellsten (1994). Union Reefs Gold Mine recovers 40 per cent of its bullion production through a gravity circuit, Riches (1997). Brocks Creek ore contains visible coarse gold with gravity bullion production fluctuating between 50 per cent and 65 per cent, depending on the mill feed. Average gravity bullion production from the Brocks Creek Mine is 55 per cent, Wilke (1997). The average gold grain size of Macraes Mine ore is 20 μm with 40 per cent of the gold in sub 10 μm particles. No gravity bullion is produced from the Macraes Mine, O'Keefe (1997). The testwork demonstrated conclusively that it is possible to prepare a representative sample for assay, of a coarse gold ore, when a Keegormill is used to pulverise the sample to a nominal 100 μm particle size (90 per cent passing a 100 μm screen by wet sieving). Both the Mixermill and the Labtechnics LM5 failed to prepare a representative sample, even when ground to a nominal 75 μm particle size.

Jan 1, 1998

By M S. Tuohy

Since the independent review of fatal accidents in the mining industry carried out by Dr Sean Brady (the ‘Brady Review’), High Reliability Organisations (HROs) and their operating principles have been discussed across the Queensland mining sector. HROs are organisations said to consistently avoid serious failures, reliably delivering their organisational objectives despite operating in environments characterised by high levels of inherent risk and/or operational complexity. HRO concepts have previously found application in other similarly hazardous industries to mining. However, as Hopkins (2009) pointed out, HROs ‘are very elusive creatures that inhabit the realm of theory more than the real world’. The Queensland Resources Council (QRC) with support from the Commissioner for Resources Safety and Health initiated a review of how HRO principles can be translated to the mining industry. The review was conducted by Noetic, an Australian management consulting company that specialises in hazardous industries, including mining and metals, and has prior experience applying HRO theory.

May 5, 2022

By Palmer DJ

Mercury is introduced into EZ's electroly tic zinc/sulphuric acid plant complex at Risdon, Tasmania, in zinc sulphide concentrate. Mercury is volatilised during the roasting operation and then distributed in the sulphuric acid plant effluents and product acid. Following an investigation of the factors determining the mercury distribution, a plan was formulated to-provide an environmentally accep- table degree of mercury containment at Risdon. This paper discusses details of the various control measures investigated and out- lines the reasons for selecting the particular procedures finally adopted for the Risdon plant.

Jan 1, 1980

By W P. Breytenbach

"The phased application of statistical process control (SPC) infers that processes are classifiable as pre-SPC (or phase zero), phase I and phase II processes, with different objectives being pursued in the different phases. Phase zero processes, defined as processes affected by assignable causes of variation, are characterised as follows: out-of-control with unknown autocorrelation structure having an unknown statistical distribution not performing consistently on target with minimum variability potentially incapable of conforming to the product specifications. The objectives of phase I SPC is to obtain estimates of the mean (µ), variance (s2), probability density function (f(X)) and the autocorrelation structure, as well as transforming the process into a phase II process (defined as a process conforming to specifications and performing on target with minimum variability). As in any other type of research or pragmatic improvement intervention, sampling is required is to achieve these objectives. The challenge of deciding a phase I sampling plan is multifarious since it has to cope with the aforementioned effects of assignable causes and provide for rigour estimates of the unknown parameters. Furthermore, deciding sampling plans in phase I invariably presents a classical catch-22 situation: appropriate sampling is required to determine the autocorrelation structure of a variable, but knowledge of the autocorrelation structure is required to formulate an appropriate sampling plan. This paper suggests, for random variables, guidelines to formulate sampling plans, and presents a methodology to estimate the inherent process parameters of process variables and an approach to identify assignable causes in phase I. CITATION:Breytenbach, W P, 2014. Rational sampling and standard deviations for random variables in phase i application of statistical process control, in Proceedings Sampling 2014, pp 141–154 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 29, 2014

By K J. Davey, J T. Woodcock

Australian steelmakers produce up to 30 000 t/yr of electric arc furnace (EAF) dust. Current disposal techniques include sending EAF dust to landfill, stockpiling, and paying zinc smelters or registered waste removalists/processors to take the dust. Many of the complex overseas pyrometallurgical and hydrometallurgical treatment routes cited in the literature are not considered economic. Governmental, environmental and social pressures on producers to consider more sustainable disposal options are mounting, and there is now a strong push to consider recovering potentially valuable or recyclable components, such as zinc and iron units, from EAF dust. As well, there remain strong economic drivers for producers to find lower cost disposal solutions. Characterisation studies undertaken at CSIRO Minerals have revealed important physical differences in the nature of the zinc- and iron-bearing phases contained in domestic EAF dusts. These differences have been exploited using simple and cheap mineral processing techniques such as water washing, wet cycloning and wet magnetic separation. This has allowed a significant upgrade in the zinc content of EAF dust to be achieved, together with a reduction in the levels of key smelter penalty elements, such as chlorides and fluorides. The zinc-rich portion of the dust is now a more attractive smelter feed while the iron-rich part of the dust could potentially be briquetted or pelletised with a reductant and recycled to recover iron, and thus close the loop on dust processing. The basis of the separations tested together with laboratory results from several Australian dust samples are presented and discussed in this paper.

Jan 1, 2006

By K M. Cook, D Clark

Fatality prevention and zero harm are key focus areas for resource companies. However, they remain an ongoing challenge for high hazard industries, including the mining sector. As one example the latest International Council on Mining and Metals (ICMM) Safety Performance Report shows that, while there is generally a declining fatality trend since the organisation commenced publishing data in 2012, there were still 33 fatalities across member companies in 2022 (ICMM, 2023b). Every fatal incident brings significant pain and suffering to the colleagues, friends and family of those involved, however the failures and causal factors leading to each incident are frequently very familiar to people working in the industry, particularly those tasked with managing risk and safety. In the words of Dame Judith Hackitt, Grenfell Tower Fire Investigator, ‘there are no new accidents – just different people making the same mistakes because they haven’t learned’ (Hackitt, 2022). The recurring themes in terms of the nature of fatal hazards and their associated causes across the mining sector show that, despite improvements evidenced by the favourable declining fatality trends over the long-term (in general and outside of catastrophic multiple fatality events), changes are required to achieve fatality elimination and the aspiration of zero harm. This extended abstract and the accompanying presentation apply a mining frame of reference to the idea that there are no new accidents, examining how this applies within the industry and why the lessons from past failures are not always well understood or applied to prevent the reoccurrence of material unwanted events. Many contemporary mining and resources organisations have extensive internal incident history data and a wide variety of information on fatality incidents is publicly available, including the annual ICMM Safety Performance Report. This extended abstract and the accompanying presentation explore how this existing data can be used effectively to learn from the past and proposes practical ideas regarding strategies for successful knowledge transfer to the workforce as a key component of preventing history repeating and improving safety performance across the industry. As noted by ICMM, ‘sharing lessons from failure is vital to improving health and safety, but it’s not enough’ (ICMM, 2023a).

Apr 16, 2024

By N J. Beukes, S T. Netshio, M O. de Kock

The Thabazimbi iron ore deposit comprises a series of stratabound orebodies, on average 18 - 25 m thick that are aligned along the faulted basal contact between the Penge Iron Formation and dolostones of the Malmani Subgroup, Transvaal Supergroup. Field geological relationships and petrographic observations suggest that the formation of high-grade iron ores took place after contact metamorphism related to the intrusion of the Bushveld Complex (2.06 Ga) but before the deposition of red beds of the Waterberg Group at ca 1.9 Ga. Hard, high-grade iron ores are predominantly composed of martite and microplaty hematite. Goethite is restricted to supergene-modified ores close to the Late Cretaceous û Early Cenozoic Old African land surface. At depth, the high-grade hematite ores interfinger with low-grade dolomite-hematite and calcite-hematite ores. Iron oxides (martite, microplaty hematite) present in these low-grade ores are texturally indistinguishable from those in the associated high-grade ores, ie ore formation is genetically associated with carbonate metasomatism. Microthermometric studies of fluid inclusions in sparitic carbonates and rare megaquartz reveal their hydrothermal origin. Two compositionally distinct aqueous fluids of shallow crustal origin are identified, namely a Ca-Na-rich high-salinity brine (26 wt per cent NaClequivalent, TH ~160¦C), and an aqueous Mg-K-bearing fluid of intermediate salinity (8.3 - 12.6 wt per cent NaClequivalent, TH~120 - 150¦C). The results confirm that high-grade hematite orebodies at the Thabazimbi deposit owe their origin to an event of extensive oxidative carbonate metasomatism (calcification), similar to that recognised at other important high-grade iron ore deposits in the world. Hydrothermal ore formation is both structurally and lithologically controlled. Size and quality of the orebodies was improved by Late Mesozoic-Cenozoic deep lateritic weathering as carbonate-hematite ores were enriched to friable high-grade ores, but this supergene modification is second in importance compared to the primary event of hydrothermal ore formation.

Jan 1, 2005

By S C. Barrie

St BarbaraÆs Marvel Loch operations have successfully used longhole open stoping as the primary mining method for a number of years. A transition to Core and Shell mining was implemented in 2009 to recover substantial ore grade resources remaining in sill and rib pillars. The transition to core and shell for the Exhibition lode required continuous waste filling of created voids and thus the removal of the crown pillar at the base of the Exhibition pit by blasting. Access to the top of pillar was denied as the pit was partially rock filled with waste rock from underground development.Beyond the technical challenges of the blasting project, a simple and transparent risk management process was developed to ensure appropriate controls and mitigating strategies were in place to minimise risk to personnel during the pillar removal process.Although failure of the crown pillar was anticipated but with the actual timing unknown, on 25 December 2011 the crown pillar yielded during normal mine operations. Engineered and isolation controls in place at the time were of a sufficiently high standard to ensure limited exposure of the underground workforce and minimal damage to mine infrastructure. Successful risk management through implementation of appropriate controls during the project lifecycle of two years and three months proved to be fundamental to the safe removal of the crown pillar.CITATION:Barrie, S C, 2012. Successful risk management through project life cycle for removal of the crown pillar at the Marvel Loch Underground Mine, in Proceedings International Mine Management 2012, pp 125-134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By L Eriksson, D Penn, J Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are, in most cases, developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, the company has placed emphasis on accuracy in the drilling process and documenting what has been drilled. By applying state of the art technology to the common automation platform, developed for the surface drilling market, major steps in improving overall drilling productivity and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the companyÆs surface drilling products.CITATION:Appelgren, J, Eriksson, E and Penn, D, 2012. Rotary drilling automation increasing operator productivity and drilling quality, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 13-18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By Lawless JV

Recent exploration for gold on the Pacific Rim has utilised similarities between active hydrothermal systems and epithermal gold deposits. The major control over formation of such deposits is the hydrology of the ore-depositing hydrothermal system, which varies depending upon its geologic setting.

Jan 1, 1987

Exploration for uranium in Australia has so far discovered reserves equal to 17.5% of the Western World's. The Australian uranium industry, when fully developed, will be one of the largest producers and possibly the largest exporter in the world. The world's nuclear industry is young, rapidly developing in size and technology and is subject to more social, political and regulatory controls than any other industry. This paper considers the probable development of Australia's uranium industry against a background of normal commercial parameters together with other factors which are peculiar to the nuclear industry. As the theme of this conference is "Australia's role in the World Mineral Indus- try" this paper concentrates on the commercial and practical aspects associated with the development of Australia's uranium resources in a world context.

Jan 1, 1979

Efficient project planning during the detailed feasibility to final engineering stages of a project requires not only the accurate prediction of the grade, tonnes and recovery, but their degree of variability as well. An understanding of the major parameters involved in the grade and tonnage estimates is essential, and the communication to those receiving the results is most important. The personnel involved in the project require more than just a global reserves classification. Quality parameters other than grade should be evaluated as carefully as the estimate itself. This paper does not present any novel ideas to overcome or enhance any of this. Rather, it takes a step back and tries to look at the global picture of requirements for proper project planning.

Jan 1, 1987

By Rayner J. G, Leckie J. F, Moorehead C. F

The Coronation Hill gold-platinum-palladium prospect is located in the valley of the South Alligator River (latitude 13'35'S, longitude 132'36'E), about 80 kilometres east of Pine Creek in the Northern Territory. Coronation Hill was one of thirteen sites in the South Alligator Valley at which uranium was mined between 1955 and 1964 after initial discovery by the Bureau of Mineral Resources in 1953. Most of the mines were operated by United Uranium No Liability. The Sleisbeck mine 25 kilometres south of Coronation Hill was operated by North Australian Uranium Corporation and the group of mines at Rockhole about 20 kilometres to the north-west of Coronation Hill was operated by South Alligator Uranium No Liability. The uranium mine at Coronation Hill produced about 26000 tonnes of ore averaging 2.6 kg/t U308 with an estimated average gold grade of 10.4 g/ gold. Gold was commonly associated with the uranium mineralisation and was recovered at the gravity treatment plant at El Sherana. Gold was also recovered in 1986 by Pacific Gold Mines Limited by treating the tailings from the Moline and Rockhole uranium leach plants at a CIP plant at Moline. With the completion of uranium contracts in 1964 mining in the South Alligator Valley ceased. Exploration for uranium continued in the area during the 1960s and 1970s with no success. The Coronation Hill Joint Venture (BHP Gold Mines Limited 45 per cent, Pioneer Minerals (Gold) Pry Ltd 45 per cent, Notgold Limited 10 per cent)carried out the first exploration specifically targetted at gold in 1984 with the drilling of five vertical drill holes which indicated high potential for a substantial gold resource at Coronation Hill with no associated uranium. The Joint Venture has sub- sequently drilled about 25000 metres of diamond drill holes at Coronation Hill alone. Analytical results from 1985 drilling established that platinum and palladium were associated with gold. An indicated resource of 3.49Mt at 5.12g/t Au, 0.21g/t Pt and 0.56g/t Pd has been calculated using a lg/t Au cut off.

Jan 1, 1991

By Stewart R. D, Lawrence W, Youl M. J

The trend towards contracting by major coal mining companies such as BHP Coal and MIM Ltd is examined. Reasons why this trend is occurring are discussed and the concept of partnering is examined. Two case studies are given: the Mt Owen Mine in the Hunter Valley, NSW and the South Walker Creek Mine in the Bowen Basin, Queensland.

Jan 1, 1997