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By G C. Reed, J M. Murray

During more than 100 years continuous mining of the lead-zinc orebody at Broken Hill, an immense amount of geological data has been collected about shear zones related to the orebody. The challenge to current mine geologists is to synthesise and interpret these data sets in a way that is applicable to production demands. Precise knowledge of the locations of major shear zones is important not only for the determination of ground conditions but also to develop an understanding of ore remobilisation along these structures. Traditionally, geological information has been collected from drill core and back and wall mapping underground, and interpreted on sections that are approximately 20 m apart. The recent introduction of MaptekÆs Vulcan software has enabled the shear zones to be modelled in three dimensions. The new three-dimensional shear models have been combined with seismic data from the Southern Cross area. The seismic data is collected from a microseismic monitoring system installed in the Pasminco Southern Operations in August 1996 (Rauert and Tully, 1998). The addition of seismic information to the shear zone models has led to a greater degree of certainty about the shear zone locations and has provided information about shear zones in areas yet to be drilled.

Jan 1, 2000

By K J ROSENGREN

Underground rock mechanics was initiated as a formal discipline in Australia by early studies for underground structures for the Snowy Mountains Scheme in the 1950s. These techniques were quickly embraced by underground mining and there has been steady development to the present time. The paper reviews the status of current techniques for rock mechanics studies and discusses some important issues such as ground support, mine filling and caving. It concludes that a considerable degree of engineering judgement is still required for the practical application of rock mechanics to underground mine design.

Jan 1, 1992

Thank you for the opportunity to speak at this important conference attended by aspiring mining professionals, some of whom will become the leaders of the mineral resources industry that forms the solid foundation of AustraliaÆs past and that will fuel the exciting growth of AustraliaÆs future.I want to briefly touch on the history of our business, then look at the opportunities that exist in the contract mining industry and finally comment on what the educators need to consider in their curriculum to meet the needs of our business. Byrnecut started out as an idea in early-1987 developed by a group of four mining people. At the time the industry was on the high end of a mining boom, the era of the Bonds, Connels, Skases and so on. Riding on this wave of euphoria we borrowed $600 000 from the National Australia Bank and, without having enough knowledge to lose sleep over the potential risks, started business in mid-1987. The euphoria quickly evaporated with the 1987 October stock market crash. The bank pulled our overdraft, equipment finance rates increased to over 20 per cent per annum and my house was mortgagedseveral times over. The business learning curve was extreme for a young mining engineer who had developed his trade in the relatively sheltered environment of a large public mining house, namely WMC. We were somewhat bitter that the banks had done a runner. We were a private company, backing the business with personal assets with our shoulders to the wheel, whilst the Bonds of the world had theirnoses in the trough ripping off mum and dad shareholders. All of this had a sobering effect, namely keep your feet on the ground, stick to the knitting, work hard and worship cash flow. Since that stressful but adrenaline pumping beginning the company now employs over 600 people and is now working for major mining houses at over a dozen locations in Australia, east Africa and WesternEurope and the National bank is again our banker. On this basis I consider myself qualified for the subject of this speech.

Jan 1, 2002

By C Skublak

The Government of Canada recently passed a new regulation to control the liquid discharges from metal mines in Canada. The Metal Mining Effluent Regulation of the Federal Fisheries Act will come into force within the next six months. As a result the Ontario Regional Office of Environment Canada has developed a compliance promotion program to accompany the new regulation. How the mines implement the regulation will be key to its success. This paper will briefly outline the components of this regulation, including the reporting structure, the discharge parameters and limits, as well as the requirement for the mines to conduct long-term environmental effects monitoring on their effluent discharge. The presentation will give a brief account of the compliance promotion program, and then focus on the spill trends from Ontario mining operations. The province of Ontario has the largest concentration of metal mining operations in the country with approximately 40 active mines.

Jan 1, 2002

With the launch of Immersive Technologies' next generation of Advanced Equipment Simulators for the mining industry, correlating and influencing safety, productivity and maintenance with operator competency improvements is now made even more effective. In early 2008, Immersive assembled a project team to investigate the potential linkages between operator competency and performance. Advanced Equipment Simulator Users with a range of sophistication were interviewed and consulted. The result was new and enhanced 'value realisation' programs to directly assist mine sites to deliver the expected return on investment (ROI) from simulators and operator competency development. In just over one year, 29 mine sites around the world have benefited from 34 completed programs. Case studies have been compiled to demonstrate the impact of the implementation of this approach, including at the following operations: Anglo Coal - Callide (Australia), Freeport McMoRAN - Grasburg (Indonesia), Equinox Minerals - Lumwana (Zambia), Peabody Energy - Cabllo (USA), and Xstrata - Lomas Bayas (Chile). Significant performance improvements have been achieved including: reductions of 47 per cent in gear shifting and 37 per cent in over speed errors, improvements of 68 per cent in park break errors and 12 per cent in spotting time, and increase of 54 per cent in passing emergency fire handling competency tests. This presentation draws on these case studies to clearly demonstrate the linkage between improved operator competency through the implementation of training programs tailored around Advanced Equipment Simulators and production performace measured by a range of standard metrics at mines around the world.

May 1, 2010

By G R. Hancock, S Grant, T Whiteside, J B. C Lowry, J Boyden, T J. Coulthard

Physically-based landform evolution models (LEM) provide a spatial framework to forecast the long-term geomorphic stability of post-mining landscapes. When used to test the relative stability of different landform designs, LEMs may assist with the development of optimal closure designs for rehabilitated mines. However, in order to reduce prediction error, factors controlling landscape evolution must also be accurately represented by models. This requires that the correct sets of processes are represented and that driving parameters used in LEMs are, if necessary, calibrated to the landscape of interest.Vegetation exerts strong controls on the hydrologic and geomorphic processes that drive landscape evolution. Hence, the spatial and temporal scales over which typical patterns in vegetation are represented in different landscapes are important considerations in LEM calibration. However, vegetation is rarely accounted for in LEMs and even when integrated is often represented simply, without representing spatial dynamics of vegetation cover that may impact landform development.This study focuses on characterising vegetation patterns to calibrate a new vegetation module of the The Cellular Automaton Evolutionary Slope and River (CAESAR)-Lisflood LEM to be applied to a conceptual rehabilitated landform of the Ranger uranium mine located in the Alligator Rivers Region (ARR) of northern Australia. In the ARR the spatial dynamics of vegetation over time are largely driven by monsoonal rains and topography. Extensive dry season fires are also common in the region, temporarily reducing vegetation cover where they occur. Hence, hydrology, topography and fire disturbance interact to shape a distinct, yet dynamic, mosaic of different vegetation types of varying cover density. As a basis for calibrating the new vegetation function, the distribution and dynamics of vegetation are characterised for this savannah landscape by remote sensing, in conjunction with ground data.CITATION:Boyden, J, Lowry, J, Coulthard, T, Whiteside, T, Hancock, G and Grant, S, 2016. Accounting for vegetation dynamics in landform evolution modelling, in Proceedings Life-of-Mine 2016 Conference , pp 63–66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By M Fewings

This paper casts a light on the sometimes murky world that lies between base metals product æout the gateÆ, and money in the bank. Whether your base metals are leaving the mine as a refined product, or as an ore or concentrate, the generally accepted method of value determination is a London Metal Exchange price, usually measured at some point after the material has left your control. In this paper, the structure and operation, regulation and the reasons for the use of the London Metal Exchange are explored. In addition, the risks and opportunities that terminal market pricing provides to mine managers are explained, with particular reference to hedging. The paper also deals with the structure of the sales contract, including management of shipping issues, agreement of delivered quality, documentation and administrative issues. The selection of counterparties, the role of traders in the market and the growing influence of China and India as base metal consumers and competitors are also addressed.

Jan 1, 2006

The 115-year history of the Hall-Heroult process for production of aluminium has been characterised by a sustained technology-driven improvement in costs and productivity. In the past decade the industry has effectively transferred best practice into older technology with improvements through computer control of the process, and redesign of cell linings using computer modelling . Incremental development is now at the point where diminishing returns will apply for further technical improvement effort however, until the gap between technical limits and current best practice is addressed through major process redesign. The process remains a long way short of its technical limits in energy consumption, carbon anode consumption, cell life and product purity. Investment cost in new capacity is very high, supporting the retention of older and less efficient technology and hence limiting the application of best practice in environmental performance and occupational health exposure. The industry is a major emitter of greenhouse gases yet the process has the potential to release oxygen as the primary waste. All of the above issues will be addressed in the new century, but only through commitment to the necessary long-term research and development that is required to achieve a redesign of the process.

Jan 1, 2000

By W C. Burton, J S. Kuszma, T O. Aspinall

The environmental impact of mining and evolving environmentallegislation has received increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental regulatory agencies and members of the public. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. There is thus the need to increase the base of knowledge on the existing practices of spoil dump design and rehabilitation. Efficient engineering design and systematic economic evaluation of spoil dump reshaping techniques for mine rehabilitation assists in maintaining the expected standards of environmental compliance. As part of the overall approach for effective engineering design ofspoil dumps, a comprehensive, computational and efficient tool isrequired for assessing the economics and productivity of existing spoil dump reshaping practices for efficient mine rehabilitation. Such a design tool is useful in linking current spoil dump environmental management practices with engineering design planning and economic impact evaluation. This paper identifies the processes for the economic impact evaluation for existing spoil dump reshaping practices and proposed final site dump designs. Selection of an efficient spoil dump design at optimum costs will ensure operational efficiency. A case study is presented identifying economic impact evaluation in earthmoving equipment selection and the costs involved for the reshaping of spoil dumps to that of varying final site designs.

Jan 1, 2000

Australia as a leading producer of mineral sands has also occupied a leading position in many areas of research'in the processing and applications of these minerals. Research in upgrading ilmenite to produce synthetic rutile has resulted in the develop- ment of many processes, e.g,., Becher, Murso, Chlorine Technology, and ICI processes. Studies on the reducibility of ilmenites, aqueous leaching of reduced ilmenites, Fe-Ti-O system, leachability of natural and treated ilmenites in hydrochloric acid and selective chlorination of iron from ilmenites have been carried out in order to develop and improve the efficiency of the above processes. While research on the processing of zircon sand to produce high purity (99.99% ZrO2 zirconia powder and zirconium chemicals started only recently, research by CSIRO in the early 1970s led to the discovery of the phenomenon of transformation toughening in partially stabilized zirconia (PSZ) ceramics. Australia, with very significant resources of lanthanide-containing ores, pro- duces substantial quantities of monazite each year but research in processing and appli- cations of rare earths was neglected in recent years in this country. However, research to improve processes for the recovery of rare earths is now under way and studies on the production and testing of Nd-B-Fe magnets which are 1.5-2 times stronger than the strongest magnets (Sm-Co) currently available, have also commenced.' An overview of the research in the pro- cessing and applications of mineral sands during the last two decades in Australia and its implications for the industry are pre- sented in the paper.

Jan 1, 1986

Recovery of Vanadium from Stone Coal Through an Environmentally Friendly Acid Leaching Technology

Sep 13, 2010

This paper describes the past, normal and advanced practice of optimisation in mining. It then discusses what needs to happen for the mining industry to make full use of what is now available.

Dec 6, 2010

By G Gosson

An important requirement in every geological quality control program is that the identity and grades of the control samples (duplicates, certified reference materials (CRMs), and blanks) must remain æblindÆ to the analytical laboratory. Once the entity to be controlled is aware of relevant details of the control process, such as the identity of the control samples, the objectivity may be lost and the control may no longer be completely valid. Whereas the blind insertion of field duplicates and coarse blanks can be easily conducted at site, simultaneously with the sampling process, the rest of the control samples should be inserted into the batches during or after sample preparation and prior to assaying, in order to ensure a proper assessment of precision, accuracy and assay contamination, independent of the internal quality control of the laboratory. Such a procedure raises the concern that blind insertion of crushed or pulverised material in sample batches prior to assaying could represent a breach in the chain of custody principle, as samples would have to be temporarily returned to the custody of a non-laboratory person in charge of the insertions. In this seemingly conflict scenario, what should we give up? Do we maintain the strict chain of custody, knowing that the laboratory will be aware of the identity of some of the control samples, or that some duplicates will not be true same-batch duplicates? Do we ignore chain of custody issues to maintain the anonymity of the control samples and insert blind same-batch duplicates, CRMs and blanks? Is it possible to do blind insertions without breaching the chain of custody? Current NI 43-101 and JORC requirements, as well as real-world QA/QC and sample security practices, are discussed in light of AMECÆs approach to the solution of this apparent dilemma.

Jan 1, 2008

Kinetics of Reclamation of E-Waste by a Bioleaching Route

Sep 13, 2010

The structure and tectonic setting has had a strong influence on gold mineralisation at the Porgera gold deposit. Here, the structural controls on the mineralisation at Porgera are discussed and placed in a regional tectonic context. The Porgera gold deposit is related to the emplacement of the Porgera Intrusive Complex. Prior to intrusive emplacement at Porgera,Papua New Guinea was affected by a major fold and thrust episode which occurred in response to arc-continent collision in the Late Miocene. After crustal shortening the region experienced a relaxation of compression which is expressed in the deformation accompanying mineralisation at Porgera. The first stage of mineralisation (stage I) is hosted by extension fractures, and is spatially associated with exposed intrusive stocks. A later episode of mineralisation (stage II) is hosted by the faults and fractures of the Roamane Fault Zone, which was active as a dip-slip normal fault during stage II mineralisation. Therefore a change in the tectonic environment from shortening to extensional tectonics can be seen at Porgera before and during mineralisation. Rapid fault-slip during stage II mineralisation may have aided high-grade gold mineralisation by subjecting hydrothermal fluids to changes in pressure, temperature, fluid-fluid and fluid-rock interaction. Uplift to form the highlands of Papua New Guinea occurred after mineralisation and was largely complete by 4.0 Ma.

Jan 1, 1995

By L Dawson, S Carr-Cornish, N Boughen, K Moffat, S Masterson

The risk and consequences of community rejection and loss of a social licence to operate is well articulated (Moffat et al 2018), however, the means for systematically managing this risk are less established. At the local scale, a mining operation is said to have a social licence to operate (SLO) when it achieves ongoing acceptance or approval from the local community and other stakeholders who can affect its profitability (Graafland, 2002). Without this social acceptance, it is very difficult for a business to operate effectively or profitably. It is well understood that social (or community) acceptance of a mine and its associated operations is a reflection of the quality of the relationship a company has with their host community (Thomson & Boutilier, 2011; Lacey & Lamont, 2014; Parsons et al., 2014; Moffat et al., 2015). Community relations are an integral part of successful mining operations and where these interactions are effective, they tend to foster mutual understanding, trust and support between a company and the host community (Kemp et al., 2006; Holley & Mitcham, 2016). Research further demonstrates that where such interactions are perceived to be procedurally fair, the increased trust created in these company-community interactions tends to lead to higher levels of acceptance of mining operations (Moffat & Zhang, 2014; Lacey et al., 2017).The challenge, however, is how to listen systematically to communities that mining and associated operations; communities that are often located across vast geographic areas and with diverse demographics. To date, traditional methods deployed to both guide and evaluate community engagement and social investment activities have been challenged to reflect the nature of the phenomenon they seek to observe, the voice of community. For example, detailed baseline surveys of community attitudes every three years by companies, as is the requirement within the policy frameworks of most large miners, provide rich insights but do not reflect the dynamic, temporal nature of the relationships that underpins their SLO. These processes typically are largely opaque to communities and distinct from the company’s engagement activities. The CSIRO Local Voices project was developed with Rio Tinto to go some way towards meeting this challenge of how to listen to the voice of community systematically. CITATION:Moffat, K, Dawson, L, Carr-Cornish, S, Boughen, N and Masterson, S, 2018. Listening to Local Voices – a systematic approach for understanding what a social licence to operate means for Rio Tinto in the Pilbara, in Proceedings Life-of-Mine 2018, pp 8–11 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By M J. Davies, R S. Davies

Despite increased expenditure, the global discovery rate of world-class ore deposits has been in decline for over a decade (Schodde, 2017). Mineral exploration has traditionally followed an empirical approach, searching for evidence of mineralisation upon the surface of the planet, then drilling to define the extent of an ore body beneath the surface. As outcropping deposits in well-defined areas are depleted, there is a need for exploration to extend to less well-explored search spaces. One popular new frontier is exploration at greater depths beneath the Earth's surface. However, exploring for deep deposits with limited surficial evidence requires the implementation of predictive targeting methodologies (Hronsky, 2011; McCuaig & Hronsky, 2014). The Mineral Systems Concept (Hronsky & Groves, 2008; McCuaig et al., 2010) provides a framework for predictive exploration targeting. Ore deposit formation is recognised to be a focused mineralising event. These events represent self-organising critical systems and are underpinned by the interaction of complex, non-linear processes. Through the collection and analysis of datasets that map mineralising processes, it may be possible to predict the size and location of resultant ore bodies. CITATION: Davies, M J and Davies, R S, 2018. Beyond below-ground geological complexity: Developing adaptive expertise in exploration decision-making, in Proceedings Complex Orebodies Conference 2018, pp 95–98 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By P Micale

Geological data provides the foundations for the mining value chain. It is used to underpin the modelling and planning and consequently optimise downstream business decisions. However, it is often forgotten or taken for granted. End users often assume the data to be sound without verification. Geological data can be considered a company’s number one asset. Subsequently, the storage, use and management of this data need careful curation and time invested in preserving and protecting it. An established polymetallic mine with 20 000 drill holes could have a data replacement value in excess of $500M at 2020 prices, excluding labour and salary costs. The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the ‘JORC Code’) provides guidelines for Public Reporting. Within the code, Table 1 requires discussion around the different types of geological data, its collection and use. What is needed is additional details regarding the validation and integrity of the geological database. A comprehensive guideline specifying minimum geological standards for geological databases has been developed. This expands on the critical points outlined in Table 1 of the JORC Code. This guideline can be used by companies where geological databases are managed in-house or used to assess these services’ outsourcing. This guideline will ensure that geological data is reliable and unadulterated and can be used with confidence. Using this guideline will assist in preserving the investment of geological data in the mining value chain

Mar 22, 2022

With the continued implementation of stricter limitations on the discharge of excess process water from all existing and future mining and metallurgical operations, the design and operation of the entire process water circuit must form an integral part of any total operational package. It is far better to æanticipate and circumvent the problemÆ rather than be forced into an expensive remediation program after the event. By far the greatest problem relates to the treatment and disposal of what is generically known as acid drainage. In simple terms, an acidic metal sulfate solution is generated by a series of chemical and biological reactions as soon as most sulfide minerals are exposed to air and water. Treatment of this solution by one or more of a wide range of chemical and physical options can involve substantial capital and operating costs, although there are recent processing options that yield saleable by-products, thereby reducing the financial liability of what is effectively a waste stream. This presentation provides an overview of the Australian situation compared with the rest of the world and outlines the basic features of a number of the more advanced passive and active acid drainage options.

Jan 1, 2004

By J Lea, P Hatherly, J L. Edwards

Coal exploration has traditionally involved the acquisition of data to enable a resource to be quantified and qualified to the extent that its economic potential can be determined. This process commonly relied on: drilling to determine the depth and thickness of coal seams, broad characterisation of the overburden and interburden, and to provide cores for coal quality analyses; basic wireline logging to cross-check the depth and thickness of coal seams and provide some indication of rock mass strength; and basic surface geophysics and remote sensing to identify major geological structures. In recent years, the adoption of the JORC Code as a basis for the reporting of resources and reserves has placed a greater emphasis on the need for detailed, reproducible data sets that not only satisfy the traditional requirements of mine planners, but also satisfy the governance requirements of corporate and financial institutions. Similarly, the development of sophisticated numerical modelling techniques for use in both open cut and underground mine design, has seen a greater demand for precise geotechnical data, in situ stress characterisation and hydrological information as routine input to the design process. These requirements, coupled with the prevailing trend toward high capital, relatively inflexible mining techniques less tolerant of geological surprises, and the need for consideration of environmental issues such as groundwater impacts and surface subsidence, requires that modern exploration programs be multifaceted, and designed to commence capturing data relevant to ædownstream issuesÆ even during the initial phases of exploration planning.

Jan 1, 2009