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By B Dodd

This paper details how the Australian Securities and Investments Commission (ASIC), as a disclosure and conduct regulator, approaches regulation of continuous disclosure, capital raising and control transactions in the mining and resources sector, and the reasons for the approach. In examining this topic the paper considers the Joint Ore Reserves Committee (JORC) Code (JORC, 2004), the VALMIN Code (VALMIN Committee, 2005), the relevant ASX Listing Rules and the relevant provisions of the Corporations Act 2001 (Corporations Act). This paper discusses ASICÆs approach to expert reports and disclosure with reference to Regulatory Guides 111 Content of expert reports and 170 Prospective financial information.CITATION:Dodd, B, 2012. Issues in capital raisings and disclosure, in Proceedings International Mine Management 2012, pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By S Juras

To our geologists at Eldorado Gold Corporation, the release of the gold assays on a new ore zone causes a flurry of excitement. But to our metallurgists, that news is often greeted with the question ‘What’s the sulfur grade’? In our company, we operate and manage projects whose end-product will either be auriferous sulfide flotation concentrate or gold doré. Almost all of the steps in the ore processing are related to sulfur (in this paper specifically sulfide sulfur). So why do we geologists wait until late in a project or into production before collecting sulfur data for mine planning and ore control purposes?Gold deposits associated with sulfides commonly use a metallurgical process that begins with a flotation step to recover gold into a smaller mass known as flotation concentrate. Often, this step solely targets the sulfide minerals with gold only coming along for the ‘ride’. As a result, the gold grade in the concentrate is primarily influenced by the ratio of gold to sulfur in the feed. Should this concentrate require a refractory process downstream (eg pressure oxidation), knowing sulfur grade is critical as sulfur controls heat balance in the process. Regardless, we need sulfur models to be as robust as gold models, and created much earlier in the project evaluation process.Sulfur models require quality data collected at the same density as gold samples. Analytical methods must match expected grade ranges and quality assurance quality control (QA/QC) protocols and must be of the same integrity as in use for gold. Sulfur models will then be created by their own data analyses, interpolation protocols and validation. Furthermore, ore control systems should be designed for regular sulfur monitoring to ensure and enhance downstream value. Given time it should become habitual for geologists to likewise ask, ‘And what’s the sulfur grade’, or more specifically, ‘What’s the gold to sulfur ratio’?CITATION:Juras, S, 2017. Sulfur – the new geometallurgical grade in gold-sulfide deposits, in Proceedings Tenth International Mining Geology Conference 2017, pp 199–202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By S Joyce, Z Agioutantis, D van Zyl, D Shields

Over the past 15 years, the mining industry has begun to incorporate the concepts of sustainable development and sustainable mining practice across the life cycle of mineral operations. This requires addressing economic issues, community impacts and concerns and environmental protection, and is captured in part by the phrase ‘design for sustainability’ (McClellan et al, 2009). Over the same period, the industry has seen a gradual decline in ore grades for many mineral commodities. As a result, large volumes of tailings and mine waste rock are being produced around the world, and it is expected that the annual production volumes of these materials will increase, even if there is not a significant change in the demand for materials.Another related thread of change has been the realisation that societies need to move away from linear economies (raw materials, production, consumption, disposal) towards more circular ones. This will help societies become more resource efficient, which is defined by the United Nations Environment Programme as reducing the total environmental impact of the production and consumption of goods and services, from raw material extraction to final use and disposal. The goal is to create more with less and deliver greater value with less input. Circular economies require thinking in terms of the waste hierarchy (reduce, reuse, repurpose, recycle, recover, landfill).The challenge is that the waste hierarchy was originally designed to address embodied mineral content in products rather than mine waste and tailings generation. It will need to be reconsidered in a mine life cycle context, focusing on a value-based conception of waste (Van Ewijk and Stegemann, in press).In parallel to these changes, it has remained an imperative in the mining industry to dispose of these waste materials as economically as possible while protecting the environment. Single handling of these materials has been the main target, which reduces the life cycle costs of their management but may make reuse of waste and tailings technically more difficult or economically infeasible.This presentation explores a rethinking of the large volume earthen material waste issue at mines. The underlying theme is that some or all of these materials can be valuable resources for the future that can positively contribute to sustainable development. These resources can offer economic gains to firms, communities and societies; contribute to environmental well-being; enhance social interactions with the previously mined landscape if handled properly; and, with proper policies in place, reduce governance commitments. Each of these topics will be briefly explored. This will be followed by a discussion of approaches to manage design and operations to allow future resource recovery.CITATION:Van Zyl, D, Shields, D, Agioutantis, Z and Joyce, S, 2015. Waste not, want not – rethinking the tailings and mine waste issue, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 7–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By N J. Goodman

The HIsmelt technology was developed and proven in Western Australia (WA) after more than 30 years and several billion dollars of research and development. The HIsmelt technology was transferred to China and is now successfully operating at the Molong plant in Shandong Province, China using WA iron ore fines as the major feedstock. Several more plants are under construction in China, and the technology has been approved by the Chinese Government as an environmentally acceptable alternative to the blast furnace. The unique flexibility of the HIsmelt process offers multiple pathways to decarbonise the production of steel in the near future. These pathways include:  Use of sustainably grown biomass converted to Biochar to replace coal as the reductant.  Pre-reduction of iron ore fines using hydrogen or biomass to direct reduced iron (DRI) powder.  Capture of carbon dioxide from the HIsmelt off gas and geo-sequestration underground. These pathways are highly suitable for the Australian iron ore industry as they utilise:  The large areas of land and long growing season available in Australia for the production of large tonnages of sustainably grown biomass.  Coarse iron ore fines directly without the need for fine grinding and pelletising.  Existing oil, gas and other underground gas reservoirs to store carbon dioxide. The HIsmelt technology will allow Australia to transition from ‘Asia’s quarry’ to Asia’s supplier of low cost, low carbon and high quality metallics that are required to produce ‘green’ steel with net zero carbon dioxide emissions. In addition, HIsmelt pig iron can be converted locally into steel via electricarc or basic-oxygen steelmaking furnaces to supply all of Australia’s demand for green steel.

Nov 8, 2021

By S Juras

The terms measured resources and proven reserves denote the highest level of estimation confidence in all of the major classification schemes. But what do they really bring to today’s project or mine with respect to production planning and expectations? Initial reserve declaration does not need measured resources, just indicated resources. Economic viability of a project is assessed on total reserves with nary a bonus for the amount of proven reserves. Production plans are based on grade and tonnage goals that may only coincidently correspond to proven reserves. So are the measured and proven categories still relevant? Historically, and almost exclusively in underground mines, companies only allowed mining in areas of proven reserves. Some companies still follow that philosophy. But many others will mine a mixture of probable and proven reserves without hesitation. Also what of the undeveloped project in a new district – what is to be made of their declared measured resources and proven reserves? Measured resources are commonly set either by some type of proximity to data scheme or a matter of ‘feel’ based on the qualified person’s experience. The parameters for reserve conversion focus on the project as a whole and then a portion becomes classified as proven reserves almost solely based on whether the resource category is measured. So should the mining industry continue to use these categories of resource and reserve classification? This paper will present arguments about making these categories once again more relevant. A more disciplined usage of these categories may re-introduce their relevancy in public disclosures of resources and reserves. As well a more consistent usage in operations may lead to increased confidence in managing production targets and costs.

Aug 22, 2011

By L P. Gray

"From paving the way in gaining approval for the first metalliferous in-pit tailings storage facility (TSF) in Victoria, to developing a deposition methodology to optimise the storage capacity and provide a final rehabilitated surface which replicates the premining topography, in-pit tailings storage has proven not only to be a cost-effective means for tailings management at Fosterville Gold Mine, but also one which provides significant economic, social and environmental benefits. Coupled with ongoing raising of the existing above ground TSF and commissioning of a new above ground TSF, Fosterville Gold Mine have to date effectively used three open pits for in-pit tailings storage, with one of the pits currently progressing through the capping and vegetation establishment phases of closure.This paper presents the process adopted by Fosterville Gold Mine in their flotation tailings management, from design and operational phases through to rehabilitation implementation. Included within the paper are challenges which have arisen during the process, and a discussion on principals behind the designs and lessons learnt during operation of the facilities.Citation:Gray, L P, 2016. Full Cycle Tailings Management at Fosterville Gold Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 369–378 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

Forty years ago Dr Pierre M Gy, a metallurgist, introduced variography as applied to monitoring a process. Consequently, his followers used the variogram to elaborate meaningful process control charts, especially since 1993. The name æChronostatisticsÆ was suggested several times by Gy as a logical name for this new science. The intent was to draw a parallel between the variogram identifying the variability components affecting a process parameter as a function of time, and the variogram used in geostatistics identifying the variability components of a given mineral content as a function of space. Heterogeneity problems encountered have indeed strong similarities. However, there is a fundamental difference. The variogram used in geostatistics is often stationary within a given type of mineralisation. While investigating a dynamic process through Chronostatistics, there is no such thing as a stationary variogram. Still, the evolving variogram provides essential information about subtle, often overlooked process difficulties. Chronostatistics is especially useful for management to take advantage of existing data that are often a forgotten source of valuable information to pinpoint recurring structural problems. The superiority of Chronostatistics over conventional statistical process control approaches is that it links observations to the inherent heterogeneity of materials under investigation, therefore to the sampling theory. Chronostatistics is like opening a new world to the metallurgist, making the process variability speak in a more comprehensive and in-depth way. Several case studies are presented to demonstrate the potency of this new science. For each of them, observations lead to solutions for continuous process improvement, therefore attractive economic opportunities. The philosophy is this: if a control chart shows a process is out of control, it must also suggest logical and pragmatic directions for solutions. The intent of this presentation is to vastly expand on these valuable, almost forgotten ideas.

Jan 1, 2006

This paper talks about the experiences of groups we have worked with over the last few years in the Asia-Pacific region (Australia, Canada, New Zealand and Papua New Guinea) and the ways that they have worked to bridge the divide between traditional and introduced structures, governance at a regional level and the introduction of traditional values into monitoring and evaluation practices. In doing this these groups have created structures and processes which have helped them engage both more effectively with external stakeholders while maintaining the legitimacy of their own operations with their own constituents. These are important ideas for those involved in the mining industry that could provide a number of very tangible benefits to mining firms and their engagement with these kinds of groups.

Jan 1, 2009

By L O’Connor, S C. Dominy

"Geometallurgy is an important addition to any evaluation project or mining operation. As a discipline, it seeks to maximise the net present value (NPV) of an orebody while minimising technical and operational risk. It also aims to promote sustainable development and initiatives by ensuring that all stages of extraction are performed in an optimal manner from a technical, environmental and social perspective. To achieve these goals, development of innovative technologies and approaches along the entire commodity value chain are being established (Glass, 2016). Geometallurgy has been shown to increase operational stakeholder collaboration, creating an environment for knowledge sharing and improved data acquisition and interrogation, with the end result being the integration of such data into mine planning and scheduling. All of these aspects create better business optimisation, utilisation of staff and targeted and realistic key performance indicators.The mining industry faces numerous challenges including, but not limited to:declining ore gradesgeometrically and/or internally more complex depositsdeep-seated deposits, with potentially high in situ stress regimesincreasing quantities of mine waste that needs to be managed appropriatelyhigher energy, water and chemical costsprocessing of more challenging and refractory ores – textural complexitiesstricter environmental/permitting conditions – so-called ‘licence to mine’increasing demand for specialist metals (eg rare earth elements, In, Ge, Te, Rh, Se, Ga and Li)commodity market volatilitya difficult funding environment.Given these challenges, geometallurgy provides the opportunity to control or at least manage some of them.CITATION:Dominy, S C and O’Connor, L, 2016. Geometallurgy – Beyond Conception, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By A Marta

Geomembrane (GMB) liners are being used more frequently for the storage or capping of mine waste due to stricter regulatory requirements relating to environmental protection. The longevity of any liner system will be a function of environmental conditions, design (including materials selection), construction and condition monitoring during operations or closure. Based on experience and case studies, this paper presents a review, from design to handover, of some of the smaller and often overlooked details that can have significant impacts on the performance of the GMB and the project overall.The topics covered will include approaches to selecting and testing GMBs to ensure they are suitable. Design considerations to aid installation and quality assurance during construction. Understanding action leakage rates and the consequences of leakage when it creates whales. Construction quality control and assurance procedures, including a brief discussion on non-destructive liner integrity testing. CITATION:Marta, A, 2018. Geomembranes – from design to handover and some of the lessons learnt, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 190–207 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By L Clarkson, D Williams, P Redcliffe, F van der Wal

This research presents a snapshot and insight into the trends, patterns, and common considerations identified in the current standing of real-time tailings dam monitoring practice. Based primarily on information derived from concurrent research by the author (in form of a Catalogue of Real-time Instrumentation and Monitoring Techniques for Tailings Dams), challenges and opportunities when transitioning to a real-time monitoring system are discussed. Learnings and key considerations between different monitoring approaches are explored, including themes of limitations and advantages that were observed consistently through global supplier feedback.

Jul 1, 2021

By R van Wyk

In today’s mining environment the use of heavy mechanical devices and other high-tech electronic devices like two-way radios, cellular phones and even automated mining systems, form a vital part of the daily operations of a mining site. These human-made devices and some of the naturally occurring events, like lightning and gamma radiation, can have negative effects on electronic detonators and the associated control equipment.On larger mining operations the necessity to move the point of safety for blasting further away from the blast area, introduced remote firing via radio frequencies for electronic detonator systems. Other influences on electronic detonators can be abuse or ignorance. To ensure the safety of the end-user, an electronic detonator must be resistant to some common mistakes that users can make. One of main concerns here is resistance to static discharge or incorrect wiring. Despite the daily use of electronic detonator solutions, scepticism and concern still exists amongst those who believe the system raises the risk of a premature initiation of the blast through some form of interference trigger.This paper will help users understand how electronic detonators and the associated control equipment protects itself from external influences. Focus will be on protection schemes to counter static and over-voltage discharge and methods to ensure protection of secure wireless radio links and detonator communications. With well engineered communication systems and solid static and over-voltage protection, an electronic detonator system can be more reliable and safer than other detonator systems. The following main points will be discussed:what makes a detonator an electronic detonator,static electricity and over-voltage protection,the general influence of electromagnetic energy on the detonator,the influence of lightning on detonators,the protection of radio communication’s links as used by remote firing equipment, andthe safety protection features built into remote firing equipment.

Nov 8, 2011

By J Schrank

Double-stack trains in the United States date back to the early 1980s, starting about the time deregulation of the rail industry occurred. Freight rail became increasingly more competitive to trucking and barge or ship, and led to major investments in railroad infrastructure. Since most railroad tunnels in the United States were constructed between 1880 and 1930, they were not built tall enough to accommodate modern double-stack intermodal railcars. Therefore, as double-stack trains became the norm, existing tunnels became bottlenecks, and railroads wanted the tunnels made larger without impacting traffic. This need to increase the clearance while not impacting rail traffic launched a very specialised industry: the design and construction of replacement lining systems in existing tunnels.Several large multitunnel railroad clearance improvement projects have been completed in the country in the last decade, and they have all been done under ‘live track’ conditions. Live track conditions consist of work windows, often anywhere from four to 12 hours, that are provided to the contractor to complete the construction work. By the end of each work window, the tunnel must be secured so that the railroad can run trains.In addition to improving the clearance, these projects provided the railroads with an opportunity to improve the general condition of the tunnels, including structural, seepage, drainage and icing conditions. This paper discusses the design considerations, tunnel assessments and construction methods used for these live track railroad tunnel projects. Seepage and drainage improvements that were incorporated into the clearance improvement projects are also discussed.CITATION:Schrank, J, 2014. Live track railroad tunnel repair and clearance improvement in the United States, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 619–628 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By D J. Brake

In most underground mines, the ventilation system is a significant portion of the total mine capital and operating cost and the largest consumer of underground electrical power. The effectiveness of the ventilation system has a major bearing on the safety, health, comfort and morale of underground personnel, and has a critical role in meeting production targets and therefore business revenue. Perhaps the most important component of the primary ventilation system is the primary fan. Correct performance testing of the primary fan during the warranty period is important not only to ensure the mine has obtained the asset that it paid for and can therefore deliver on the fanÆs crucial safety and economic role in the future of the mine, and to provide a justification for releasing final performance warranty payments to the supplier, but also to provide a benchmark or baseline against which to assess future performance issues. As there are at least three potential international standards available to measure fan performance, there has been considerable confusion regarding which of these to use for testing primary mine fans, and also the correct allowances and tolerances to use. This paper provides guidance on which standards to use for different applications, how the standards should be interpreted, what allowances and tolerances are reasonable, and other important issues to be resolved with the fan supplier prior to making a contract award. The paper also discusses practical issues and methodology for in situ primary fan performance testing.CITATION:Brake, D J, 2013. Performance and acceptance testing of main mine ventilation fans, in Proceedings The Australian Mine Ventilation Conference , pp 141-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By P D. Munro

"This is a reprise of the paper ‘Back to the Future – Why Change Doesn’t Necessarily Mean Progress’ presented to the Tenth Mill Operators’ Conference in 2009. It was observed that the ‘boom and bust’ cycles of the industry, together with trends in tertiary education and the effects of fly-in fly-out (FIFO) operations raised serious questions about the sustainability of human capital in the mineral processing sector.In 2016 we find ourselves in a ‘bust’ after enjoying a decade of the longest commodity price ‘boom’ in a century. In the ‘boom’ did we:make any technological breakthroughs?put measures in place to improve our human capital, especially in the area of ‘professional formation’?The paper makes observations on the current performance of mineral processing engineers and the organisational milieu in which they operate. It questions whether mineral processing engineers are actually ‘adding value’ at some sites given their organisational and operational practices.Some technical trends are examined and what it might mean for mineral processing engineers.Given the above and demographic trends for mineral industry professionals, changes to the seemingly current laissez-faire model of professional development are proposed.Citation:Munro, P D, 2016. Back to the Future - Still on the Dark Side, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 341–348 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By P F. Hodkiewicz

"Our understanding of mineral resources relies on three basic steps: data capture data interpretation model construction. Until recently, all three of these steps required significant time and manual effort to produce a single resource model for mine planning, typically taking more than a year to progress from drilling to the final block model. Over the past several years, BHP Billiton has been developing innovative workflows in rapid resource modelling projects to significantly reduce these time constraints and make the process more productive by replacing manual activities with automated ones. Rapid resource modelling is the process of combining recently developed off-the-shelf technology with internal technology developments to fundamentally change the way we collect, interpret, model and evaluate geoscience data. Initiatives include automated systems and standardised workflows to make it safer, faster and cheaper to continuously update multidiscipline resource models. Specifically, rapid resource modelling workflows combine: real-time analysis of drill holes and drill samples with downhole tools and hyperspectral scanning systemsautomated interpretation of drill hole intervals based on pattern-recognition algorithmscontinuous modelling workflows using implicit modelling software. This paper outlines technology developments and workflows that provide a more thorough understanding of mineral resources to support faster and more informed strategic, planning and production decisions.CITATION:Hodkiewicz, P F, 2014. Rapid resource modelling – a vision for faster and better mining decisions, in Proceedings Ninth International Mining Geology Conference 2014 , pp 183–188 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

The mining industry has expanded significantly in the Pacific Region over the past two decades through a mix of new developments and brownfields expansions of existing operations. Despite this overall success there are also a number of well publicised examples of less than successful minerals ventures. These problem developments highlight the fact that success cannot be taken for granted and that rigorous planning and attention to detail is essential. The dominant growth has come through expansion of existing businesses, notably alumina, iron ore and coal, achieved through both efficiency gains on existing plant and step change capacity additions such as new mines and/or expanded processing plant. This expansion has largely been linked to increased market opportunities. The major issues are the quality and extent of the host resource, achieving the market targets, and the efficiency of the expansion effort. There can be also a range of site specific issues which need to be addressed. The development of new greenfields operations is often more complex as it can bring a wide range of new issues. Depending on the nature of the development, and the companies involved, these can extend from initial financing through to obtaining a market position. Incorporating major new technology and/or establishing infrastructure and attracting staff to remote locations can also add significant challenges. This paper outlines many of the critical factors which need to be considered prior to proceeding with major expansions or greenfields developments. These will be linked to a number of developments in the region over the past decade.

Jan 1, 2004

By A Geldenhuis, M Hagger, J Maree

Disposal of mine water is a worldwide problem occurring in the coal and gold as well in the metal ore mining areas. Since southern Africa is a (semi) arid region, mining effluents should be treated to qualities such that they can be used for agricultural purposes or that they can be discharged in river system. Studies have shown that partly treated acid mine water can be used for irrigation. A copper mine in Botswana plans to use 5 M/d of treated mine effluent for the irrigation of agricultural product. The results of this study showed that when applying the biological sulfate removal technology the produced sulfide precipitated the metals in the mine effluent, such as nickel, Zn and Mn, to metal sulfide (MeS).

Jan 1, 2003

By P W Haines

The McArthur, Balma (new name) and Habgood Groups are thick (up to 4.5 km) correlative sequences of shallow water evaporitic carbonates, mudstones and sandstones that are exposed largely within the Batten, and southern and northern Walker Fault Zones (Batten and Walker Troughs) of the McArthur Basin respectively. Recent re-mapping of the Walker Fault Zone has provided data for refined stratigraphic correlations between these groups. Two significant hiatuses are now recognised within the Balma Group (base of Vaughton Siltstone and base of Yarrawirrie Formation) and these may represent tectonically-generated sequence boundaries which may correlate with similar local hiatuses within the McArthur Group such as at the base of the Teena Dolomite and Lynott Formation respectively.

Jan 1, 1994

By Fitzgerald DE, Taverner MG

The principles, fields of application and equipment design concepts of several new approaches to continuous vacuum treatments of molten metals and alloys are discussed. Partic- ular attention is paid to the results of pilot plant tests evaluating a launder-in-tube method of 1. continuous production of refined zinc from a zinc-bearing lead produced in the lead splash condenser of the Imperial Smelting Furnace (ISF), and 2. continuous refining of crude cadmium. The former trials were not sufficiently encouraging to justify consideration of the process for commercial development. The applic- ation to cadmium upgrading gave very promising results; metal of 99.99 per cent purity was produced continuously at pilot scale (120 lb per hour) from crude metal containing 5.0 per cent Pb.

Jan 1, 1972