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By L van Latum, A Koh, I Thomas

Haul truck drivers are at a high risk of developing fatigue due to the monotonous nature of the work and demanding shift rosters. In the mining industry, fatigue is identified as a major contributing factor in several fatal accidents a year. A number of fatigue detection devices are now available, that can contribute to improved fatigue risk management in the mining industry. This paper describes the technology and algorithms behind one particular product which is both predictive and un-obtrusive to the operator. The Advisory System for Tired Drivers (ASTiD), was developed by Fatigue Management International (FMI) in collaboration with the Loughborough Sleep Research Centre (LSRC), both in the United Kingdom. While this system includes a model of the human circadian rhythm as a bias for predicting expected fatigue risk by time of day, it also uses yaw data generated by a solid-state gyroscope in the horizontal plane. Algorithms analyse this data to determine the level of monotony of actual driving conditions and to detect changes in steering control caused by driver fatigue. During normal levels of attention, a haul truck driver applies continuous, small adjustments to the steering wheel. As the level of fatigue increases, steering adjustments become less frequent and more erratic. Differentiating between these modes of control in the highly variable mining environment is accomplished by chromatic processing of the gyroscope data. This paper will go into some detail explaining the principles behind chromatic processing and the specific application of these in detecting fatigue in haul truck operators.Technology in itself is not the solution to addressing operator fatigue, but it plays an important role in ongoing monitoring and maintaining awareness with mining personnel. Furthermore, the specific principles behind ASTiD technology support a risk-based approach to fatigue management, allowing optimisation of the mining operation for productivity as well as safety.

Sep 26, 2011

By Gyasi-Agyei Y

In recent years rapid advances have been made in the technology used for hydrology and erosion modelling of rural catchments. These advances have been driven by the growing availability of digital terrain maps that can be used to automatically define catchment properties that previously had to be manually extracted from contour maps. In addition, these models have, in principle at least, more powerful predictive capability. The author is involved in a number of projects to migrate and further develop these models for application to mine rehabilitation assessment. Current technologies for hydrology and erosion assessment (eg CREAMS, ANSWERS) are reviewed, underlying principles highlighted and deficiencies in the context of mine rehabilitation design assessment addressed. The advantages and disadvantages of the new digital terrain map tools (eg WEPP, SIBERIA) are discussed. Current work integrating these new models with existing rehabilitation design tools (eg ACIRL's ARGUS computer package) highlights the advantages of an integrated approach using digital terrain maps; cheaper, faster, lower impact and more flexible rehabilitation design. The use of novel visualisation tools to aid the design process is discussed. The paper is illustrated by applications to mine sites in Queensland and the Northern Territory.

Jan 1, 1995

By Y A. Stepanyants, J Crawford

A practical field method for determining the maximum value of the intrinsic oxidation rate, Smax , of sulfidic materials in waste rock dumps is proposed. Knowledge of the intrinsic oxidation rate of sulfidic materials distributed in a dump is necessary for predictive modelling of oxidation and pollutant generation over time. The suggested method uses the fact that drilling waste rock dumps to install probes for monitoring temperature and oxygen concentration causes large volumes of air to be injected into a dump by the drill rig. By measuring the rate of decrease of oxygen concentration along the length of a borehole immediately after installation, it is proposed that Smax can be calculated at different depths. The aims of this work were: to derive a simple, practical formula for the estimation of Smax from the oxygen concentrations measured over time, based on some simplifying assumptions; to use a two-dimensional numerical model that incorporates all the necessary physical processes to model the behaviour of an aerated dump over time for a reasonable range of dump and material parameters; and to compare the results of the two approaches to assess the validity of the simple formula as a method for estimating Smax. It has been found that the technique can provide reliable estimates of Smax when the value is of the order of 10-7 kg(O2) m-3 s-1 or greater. At the lower end of the range however the radius of the zone aerated during drilling becomes an important parameter and further work has been recommended to investigate this aspect of the method.

Jan 1, 2003

By R Benton

Since commencement of underground production in March 2006 the Kencana K1 orebody has delivered over 0.9 Mt of ore containing 1.18 Moz Au until April 2009. The Kencana deposits are part of the Gosowong goldfield located on the island of Halmahera in eastern Indonesia. The district has produced over 2.3 Moz since mining commenced in 1999 with the first two deposits extracted by open pit methods. The K1 deposit is technically challenging being a vein style deposit with poor to very poor ground conditions and a relatively low overall dip of around 45 degrees to mine grid east. It is mined under geological control by underhand cut and fill methods utilising cemented paste backfill aiming for 100 per cent extraction. With these conditions the operation was mine limited in the initial two years of production resulting in low stockpile levels for mill feed blending and hand-to-mouth mine to mill production. Mill feed rates have increased from 30 t/h to 55 t/h over this period following business improvement projects while mine production has escalated to match this increase as deeper levels of the deposit are accessed. The operation has now become mill limited. Monthly mill gold production from Kencana has ranged up to 50 000 oz with head grades ranging between 8 g/t and 122 g/t Au on a daily basis. As individual grade control assays can extend into the per cent Au range there are challenges in sampling, modelling, mining, blending and milling the Kencana orebody. At the time of commencement of ore driving in K1 the national geology team had little prior experience in underground mining and systems were in early development. The variances in feed grade and tonnages have been reduced with time as the operation evolves and business improvement initiatives are undertaken to smooth peaks and troughs in ore supply. Two such initiatives in the geology department have added over US$20 M of additional revenue per annum.

Jan 1, 2009

Natural gas was introduced to the Melbourne reticulation system in April 1969 and since that date sales to industrial consumers in the Gas & Fuel Corporation of Victoria area of supply, have increased by over 50% This increase has occurred despite the fact that the areas in which the new fuel is available have been dependent on the progress of the conversion operation from manufactured gas. The half way mark for conversion was reached in May 1970. The reason for the adoption of natural gas by industrial users is usually the result of objective financial analysis leading to the conclusion that the new fuel will give the lowest overall production cost. Many factors are involved in such an analysis of which the price of the fuel is only one. Amongst other important elements in the cost calculation are:- -ò òò -(1) The effect of fuel on product quality (2) Maintenance and handling costs for alternative fuel. In addition to economic gains for the individual user, the use of natural gas should benefit the whole community through its effect on such things as, air pollution and overseas balance of payments.

Jan 1, 1970

By M McDonald

KiwiRail has a goal of significantly improving passenger rail services to west Auckland, as part of its DART (Developing Auckland’s Rail Transport) suite of projects. The New Lynn Rail Trench (NLRT) project was a significant component of this work. The NLRT project facilitates essential doubletracking of the Western Auckland line, and provides a new commuter transportation hub within a busy town centre.The 1.5 km stretch of track through the New Lynn town centre has bisected the township for over 80 years. Double-tracking the line provided the opportunity to grade-separate road and rail, which would help to re-connect both sides of the township and enhance public amenity and safety.KiwiRail employed an Early Contractor Involvement (ECI) procurement model engaging a consortium comprising Fletcher Construction, Beca Infrastructure and Synergine to develop a Design and Construct solution.With weak soil conditions and high groundwater levels, a diaphragm wall construction method to form the trench walls was selected as the best solution. Further challenges to construction included working within a narrow rail corridor constrained by buildings along much of the boundary, and a requirement to keep the existing line open for rail services. Detailed construction planning was required to ensure rail and construction safety in a constrained space whilst building the trench walls, propping these walls during excavation, and constructing the base slab in the most efficient way possible.This paper will detail the geotechnical conditions and the additional constraints that made this rail trench a challenging structure to design. It will also describe the fi nal design and construction methodologies that were employed, that allowed very successful completion of the project.Additionally, this paper will review the design and construction lessons applicable to the current Victoria Park Tunnel project, and indeed for all future cut and cover tunnel projects in the Auckland isthmus.

Mar 8, 2011

By I Manege, S M. Bennett

The PT Kaltim Prima Coal (KPC) operation is a large scale coalmine operating on the east coast of Kalimantan (Borneo), Indonesia. Originally developed under a coal contract of work (CCOW) with the Indonesian Government, new legislation has led to uncertainty as to the actual life of the mine, the size of the operating lease or mining area, the rehabilitation compliance requirements and other areas of concern. The actual life-of-mine (LOM) plan is therefore in a constant state of flux and must be updated and modified with every new piece of information.Under the CCOW system, the mine life ran from the first year of production (1992) for 30 years (2021), with the potential to extend for a further two ten-year periods. KPC has always intended to run until at least 2041. Under the new legislation, the potential term of the CCOW (to be replaced by a mining license) is open to interpretation, resulting in KPC having to prepare plans allowing for a LOM that may end in 2021, 2031, 2041 or a range of other possible periods of time.Uncertainty about legislation (and hence the mine life) possible production rates and available work areas; variable coal prices and costs; varying management contexts; the substantial reserves available; difficulty sourcing dump space; potential rehabilitation costs and the dependence of a community of over 100 000 people on a single operation sees the LOM and mine closure teams preparing dynamic yet thoroughly robust plans that are updated on multiple occasions per year.This paper will describe the procedure followed by KPC and the potentially show stopping issues that must be dealt with.CITATION:Bennett, S M and Manege, I, ?2014. Life-of-mine planning in a dynamic environment, in Proceedings Life-of-Mine 2014 , pp 379–388 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

This is a welcome opportunity to exchange ideas about educating for a profession in mining and metallurgy, and I shall use it to highlight the ways in which educators, the industry, and the profession can help one another make that educa- tion better. This is home ground for me in more ways than one. As the executive head of a uni- versity perhaps I may speak as an educator; and there is still, I hope, enough of the metallurgist in me to allow me to speak of what we metal- lurgists and mining engineers can do to help the educators. Another interest should be declared, too. Among the educating agencies I shall focus on universities; among universities I shall further focus on my own, the University of New South Wales. I know it best; and, more to the point, we are one of the minority that offer a full profes- sional training in mining and metallurgy. Further, we are as a university very much concerned- more than most-with specifically professional education, and especially with education in the professions based on science and technology. Mining and metallurgy have of course played a central role, from earliest times onwards, in the history and development of science and tech- nology. In that role they have been both pro- ducers and consumers of new knowledge. Indeed the whole new attitude to knowledge that began to spread in 16th and 17th century Europe owed a great deal to the interests and traditions of the miner and the metallurgist. The first modern text- book of mining and metallurgy, George Agricola's De Re Metallica, is very much more than a spec- ialist handbook; it is a major landmark in intel- lectual and cultural history.

Jan 1, 1978

Problems encountered in the design, construction, acceptance, commissioning and early operation of the electrolytic zinc plant at Port Pirie are reviewed. Recommendations based on the author's experience are made for proper control of each phase of the development of new plants.

Jan 1, 1971

By C Antonio, R Narayan, A Scheuermann, S Quintero, M Edraki, M Ziemski

Tailings are mostly loose material and can be classed as non-plastic sandy silts. They also tend to have low permeability, resulting in slow consolidation (settling) rates and low shear strength, even after consolidation. These qualities make them prone to liquefaction and, therefore, physical instability. In contrast, coarse waste rocks possess high shear strength and permeability when stacked in dumps. However, air and water flow-through the voids can cause acid mine drainage (AMD) with significant undesirable environmental implications. Combining the two waste streams before disposal by mixing presents a potential opportunity to harness the desirable properties of both waste streams. This practice is termed co-mingling and is prevalent within the coal processing industry. Co-mingling of metalliferous mine tailings is, however, a relatively new concept. By combining the coarse waste rocks and fine-grained tailings streams, the fine tailings tend to fill the voids between the waste rocks, reducing hydraulic conductivity and advective air (oxygen) flow into the rocks, thus possibly reducing acid mine drainage (AMD). Conversely, tailings are introduced to large frictional particles from waste rocks, providing reinforcement, stability, and possibly improved drainage. New separation methods are being introduced to the mining sector, which have the capacity to extract waste with significantly larger particle sizes. High Voltage Pulse (HVP) is a technology in which relatively coarse particles ranging in size from 30 to 100 mm are exposed to an electric pulse discharge. This pulse preferentially fractures mineralised particles while leaving unmineralised rock (gangue) intact. The stream can then be passed via a screen, with smaller mineralised particles reporting to the undersize and removing coarser unbroken barren particles, thereby eliminating waste. Coarse particle flotation (CPF) is another emerging new technology in metalliferous mining that applies flotation separation to coarser particles than conventional flotation. These new technologies produce different tailings (waste) streams with varying physical characteristics and possibly surface chemistries. This research aims to test new tailings mixtures by applying the co-mingling concept to blend the reject streams generated by these two technologies (HVP and CPF) with the tailings produced by conventional flotation. Combining different waste streams before disposal can improve stability and potentially reduce the acid mine drainage (AMD) rate, thus enabling early access to the tailings storage facility for rehabilitation and closure.

Aug 2, 2023

This paper describes an ongoing study into the management systems developed by mining operations in Papua New Guinea to address particular public health issues in the workforce (primarily communicable and lifestyle diseases). The first stage of the study involves the analysis of the site health and safety management system documentation of three major mining operations in Papua New Guinea, producing a descriptive summary of each system. In the second stage of the study these summary descriptions are evaluated using a maturity model constructed through a detailed review of literature. Experience with the evaluation process is then used to refine the maturity model. The analysis performed in the study is used to develop a process for creating a maturity model for mine site health risk management based on a theoretical risk management framework, and refining it through empirical evaluations of the actual systems in place on site. Companies can use maturity models as a guide to organisational improvement, which in the context of the study will assist the operations in developing their systems for the management of health both in their workforce and in local communities.

Jan 1, 2007

By S Ramsay, D Povey

This paper presents recent case study data collected by field portable x-ray fluorescence spectrum analysers (FPXRF) as part of grade control activities at three separate (nickel, copper and copper/gold) mining operations. FPXRF has been under utilised for grade control in recent years, largely because the success of early versions of FPXRF was limited to a few metals (eg tin). Efforts to utilise these early versions for other metals was largely unsuccessful and created a perception that FPXRF could not be utilised more broadly within the mining sector and specifically the area of grade control. The structural setting of the analytical function within mining operations has also contributed to the under utilisation of more recent FPXRF instrumentation. The concept of FPXRF as a grade control tool straddles the boundaries of the geology and laboratory departments. As such, this option is often not considered as part of an assessment of grade control procedures for new and existing mining operations. This paper assesses data collected by Australian and New Caledonian miners using FPXRF technology as part of the grade control function and concludes that FPXRF can provide operational and cost benefits to certain mining operations.

Jan 1, 2003

By G Giles

One of the main tools used by mining operations to mitigate the risk of rock burst is the installation of a so-called ædynamic resistantÆ support system. Such systems are designed to absorb the impact of shockwaves created by mine-induced seismic events. Dynamic support must be strong and capable of sustaining high loads and, at the same time, they have to be flexible and accommodate large deformation. A dynamic support system is therefore a system capable of absorbing a high quantity of energy. Ground support systems are composed of rock reinforcement (rock bolts or cable bolts) and surface support (mesh or shotcrete). In terms of surface support, fibre-reinforced shotcrete is increasingly seen as the industry preferred solution when difficult ground conditions are experienced, including areas of high seismic hazard. A thick layer of shotcrete is certainly strong but it is by no means flexible. Normal weld-mesh has some flexibility, but it is not very strong. The Australian Centre for Geomechanics (ACG), in collaboration with Onesteel Reinforcing Pty Ltd, is currently working on a new high-energy absorption mesh that combines strength and flexibility. The new mesh can be installed with a jumbo, in a similar way as the widely used sheet of weld-mesh. This paper describes the development of this new mesh system.

Jan 1, 2008

Mid-ocean ridges host approximately 65 per cent of about 100 known sites of high-temperature venting and polymetallic sulfide deposits; most of them are located at the East Pacific Rise (EPR), while more diverse mineralisation styles occur at the Mid-Atlantic Rise (MAR). Seafloor hydrothermal activity at the EPR are related to MORB while different substrates, including MORB and ultramafic intrusive rocks, are associated with æblack smokersÆ at the MAR. Depth of hydrothermal activity ranges from 0.7 to 4.3 km. High-temperature vents precipitating Cu-Fe sulfides (chalcopyrite and isocubanite, rare bornite), pyrrhotite, pyrite (¦ marcasite), and sphalerite, and low-temperature edifices precipitating marcasite (with pyrite), sphalerite, barite, andsubordinate chalcopyrite (pyrrhotite and isocubanite are absent) occur in both environments. There are considerable differences in Fe, Zn, Cu, Ag, Au and trace element contents in ores and in theFeS contents in Zn-sulfides in these deposits. Acomparison with anhydrite and sulfide minerals precipitating from modern black smoker fluids sulfide reveals many similarities but also some important differences. Fluids with salinity values above and below that of seawater at 400¦C down to 130 - 170¦C deposited sulfide minerals. Mantle-derived He prevails in fluids trapped by sulfides in EPR 9¦N and 21¦N hydrothermal systems. Hydrothermal fluids in MAR and back-arc systems are richer in radiogenic 4He. The sulfur isotope composition varies in the different hydrothermal fields and within zones of a chimney. EPR sulfides display narrower range of d34S values, while MAR and back-arc sulfides can bedepleted and enriched in the heavier d34S isotope. The most important finding is that fluid temperature, salinity, R/Ra ratios and d34S values ranged more significantly in the polymetallic sulfide deposits than when measured directly on venting fluids. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Trendell B

While objective selection and assessments are an accepted part of employing managers and other staff, they have had only a limited place when selecting mineworkers in Australia. Wambo Mining Corporation has used occupational testing as part of its recruitment process since 1994. For managers and staff in particular, it is considered this has contributed significantly to a 95 % fit of those appointees. In 1997 when Wambo undertook development of a new "on site" subsidiary underground mine called Wollemi Services, they wanted to select the most appropriate people in terms of skill and on the job performance. To achieve this they reviewed and improved their recruitment processes to facilitate selection and transfer of an initial intake of almost 50 staff and mineworkers.One of the issues for Human Resource Management was to provide an environment where employees could let go of previously held (but not necessarily individually believed) entrenched views about individual performance and assessment. It needed to be emphasised that performance could be objectively and fairly assessed. More importantly, the performance being assessed was the application of skills and that new skills could be learnt and individuals could choose to change Behaviour.

Jan 1, 1998

The Australian Mineral Industries Research Association, set up by the mineral industry in 1959, acts as a research and development broker and manager for the industry. In 1984/85 it contracted out just over $3 million of projects. Its structure and method of operation is described and highlights of some of the successful projects are given. The complex process of developing new proposals is described. This involves the establishment of effective communication networks within the industry and between the industry and research personnel working outside it. The advantages of the industry tackling some of its problems on a jointly sponsored basis are listed. Possible avenues for future development by the Association are given.

Jan 1, 1986

By R R LARGE

In the past decade mineral deposit models have become an important tool for the exploration geoscientist. By combining genetic theories on the formation of particular deposit styles, with geological, geochemical and geophysical criteria relevant to ore location, it has been possible to more effectively focus exploration effort to the regions and local targets which have the best chance of success. However, such models have their limitations, and must be carefully and critically applied and continually updated as new technical and research information becomes available.

Jan 1, 1992

By Dr Subagyo

The energy consumption for producing metal from ore is strongly linked to the chemical stability of mineral being processed, availability and richness of the ore, and process route. Energy efficiencies are particularly linked to the process route. The energy efficiency of high temperature operations vary considerably but energy efficiencies greater than 70 per cent are achieved for large-scale metal production. Low temperature processing through grinding, leaching and subsequent electrowinning use large amounts of energy. In particular, grinding and electrowinning suffer from low overall energy efficiencies. The physical chemistry of a new proposed low temperature route, reactive ball milling, is unclear but preliminary evaluations indicate that it is likely to suffer from high energy consumption. In conclusion, low temperature processing routes for metals generally consume more energy that comparable high temperature processing routes.

Jan 1, 2002

In the future, Illawarra Coal, the primary metallurgical coal producer in the southern coal fields of New South Wales, will face many unique challenges not found in other coal or minerals production areas. To manage these challenges and determine the best strategy for the business, Illawarra Coal has adopted a systematic strategic planning process, which starts from the broadest possible options analysis and culminates in a ægo-forwardÆ operating case that individual mine sites use as the basis for short-term planning. This paper will discuss two major topics. Firstly an overview of the Illawarra Coal and BHP Billiton strategic planning processes. This will demonstrate the range of variables and inputs that are required for the planning process, and the system which is followed to evaluate different alternatives for the extraction of the resource. Secondly, having discussed the primary external and internal factors that must be accounted for in the planning process, and the main issues affecting the viability and likelihood of each alternative, the paper will discuss the particular challenges that Illawarra Coal will face in the coming decades. These challenges include: market and price uncertainty; managing impact on surface features, infrastructure and environment; community interaction; transport and logistics constraints; unknown mining environments; lack of geological knowledge; limited surface access for new mining domains; changing attitudes to longwall mining in the Illawarra; ageing workforce; and cost and overhead management. The paper intends to discuss how these issues impact the business currently and how they are incorporated into Life of Asset plans and overall corporate strategy for Illawarra Coal.

Jan 1, 2007

By J L. Kanau

In this study some drawbacks of using Bond grindability as a measure of grindability characteristics for mill control have been discussed. After reviewing the merits of alternative methods of determining the Bond grindability published in the literature, a new alternative method has been proposed.

Jan 1, 2000