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By R Ulusay

Rock mechanics involves characterizing the mechanical properties and behaviour of rock material and the natural discontinuities of the rock mass, while rock engineering is concerned with specific engineering circumstances, for example, how much load will the rock support and whether reinforcement is necessary. Rock engineering models developed depend considerably on the input data such as boundary conditions, the properties of rock material and rock mass. Correct evaluation of these properties frequently requires laboratory and in-situ tests, supplemented with a high degree of experience and judgment. Accordingly, since 1974, the ISRM Commission on Testing Methods has spent considerable effort in developing a succession of the ISRM Suggested Methods (SMs) for different aspects of rock mechanics and rock engineering with the contribution of a number of working groups and cooperation of some other ISRM Commissions. This paper emphasizes the need and importance of standardization of rock testing methods within the context of the ISRM SMs, gives a guideline for developing ISRM SMs and finally discusses on some implementation and contractual issues associated with rock testing and experienced in practice, and briefly introduces main future trends in rock characterization, testing and monitoring. This is an extended abstract only. CITATION:Ulusay, R, 2018. Standardisation on rock characterisation, testing and monitoring with emphasis on ISRM suggested methods, practical issues and difficulties, and future trends, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 17–18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Collings P. S, Adair D. L

The Upper Robe (Robe Gorge) deposits occur in Kumina Creek and the Robe River, some 20-40 km upstream from mining operations at Pannawonica. The Gorge Deposits were rec- ognised, mapped and sampled in 1962-3 and re- examined in detail in 1971. Approximately 180 mineralized occurrences were mapped in 1971 on 1:4800 scale and 50 of these were remapped in detail at 1:1200 scale. Eighty cross sections were measured and sampled and 300 geological maps prepared. In addition 88 holes totalling 7388 feet were drilled in three occurrences considered to have the greatest potential. The Gorge Deposits occur in the Robe Pisolite unit which forms thin remnant crusts, bay fillings and occasional cut-off meanders along the edge of the present streams. Less than 50 of the deposits have tonnage potential of one million or more. Consequently exploit- ation of the Gorge reserves must be considered as a very uncertain, long range possibility because the deposits are small and scattered throughout the gorges in the area, thereby necessitating costly railroad spur lines to gain mining access. Grade of the occurrences is extremely variable over short distances both vertically

Jan 1, 1973

By R Grogan

The Ungay-Malabago polymetallic deposit, currently owned by Lafayette Mining, is located on the eastern end of the island of Rapu-Rapu which lies east of the city of Legazpi in the Philippines. The island is sparsely populated and has largely been deforested by extensive logging some 30-40 years ago.The deposit is situated on a plateau some 200 m asl and lies about one kilometre inland from the coast. The site topography is difficult with minimal flat areas for plant facilities. The region around Legazpi is subject to volcanic activity and though the island is not affected it is in a seismic zone. There is no other mining or other industrial activity on the island, the local inhabitants being engaged in subsistence farming and fishing. These activities place a high level of responsibility on the mine operator with regard to the environment and the provision of employment and training to the local inhabitants. Although no previous mining was carried out at Ungay, shallow pit mining for high-grade direct smeltable copper ore has occurred during the mid-1900s in an area, known as Hixbar, some 2 km west of the deposit This area is currently being explored by Lafayette.

Jan 1, 2002

In recent years new instrumentation and digital technology have Wrote possible a new facet of goo-physics: broadband seismology. From digitally record-ing networks and arrays. broadband scistnograrns of body waves that are flat to displacement and veloc-ity in at least the frequency range from 0.01 to 5.0 liz can now be routinely obtained for most carthquakes of magnitude greater than about 5.5. In contrast to data from conventional narrowband seismographs, broad-band body waves have sufficient spectral information to nvest,igate the many frequency-dependent eflects that may arise from source finiteness and from wave prop-agat ion phenomenon. Besides the usual parameters of depth. moment and focal mechanism, broadband data have sufficient spectral information to provide estimates of radiated energy, associated stresses and the frequency dependence of source parameters. Moreover. teleseis-mically recorded broadband data and near-field strong motion accelerograms overlap in the frequency band be-tween about 0.1-2.0 Hz. Thus. v it h broadband data it is possible to connect far field and near field data in order to make estimates of acceleration for almost any seismically active region of the circum-Pacific.

Jan 1, 1990

By G Mudd, N Haque, S A. Northey

Life cycle assessment (LCA) provides an internationally standardised framework for estimating the environmental impacts associated with products or services (International Organisation for Standardisation, 2006). A particular strength of LCA is the ability to consider indirect impacts that occur at different stages of a product’s life (eg raw material acquisition, manufacture, use, disposal or recycling) and through its supply chain (Figure 1). A wide variety of impact categories are able to be considered by LCA, such as the potential contribution to global warming, ozone depletion, marine eco-toxicity or freshwater eutrophication.CSIRO has a long history of using LCA to compare the environmental impacts associated with alternative mining, mineral processing and metal production technologies (Haque and Norgate, 2014; Norgate and Haque, 2012, 2013). These ‘mine-to-metal’ assessments have primarily focused upon estimating embodied energy and greenhouse gas impacts associated with these production processes; however, more recently there has been a refocus to also consider consumptive water-use impacts in more detail (Northey et al, 2014).CITATION:Northey, S A, Haque, N and Mudd, G, 2016. Water-related data requirements for improved life cycle assessment of mining, mineral processing and tailings management, in Proceedings Life-of-Mine 2016 Conference, pp 16–18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

Our modern cities are almost incapable of sustaining themselves without subsurface infrastructure, which is not identifiable at first glance. This very soon becomes evident when the chaotic conditions prevailing in some cases in the multi-million cities on the African, Asian and South American continents are taken into consideration. This does not simply apply to the hopelessly congested streets in the downtown areas. If anything, it is shown here too that a subsurface infrastructure represents an important prerequisite for public health right up to banishing the danger of disease. Even during the 1990s, this has been clearly underlined through examples of cholera and plague epidemics in parts of Central and South America as well as on the Indian subcontinent. The overriding significance of an inner urban subsurface infrastructure in order to create decent conditions in the major built-up areas was once again emphasised not all that long ago at the United Nations HABITAT-II Conference in Istanbul, Turkey, in June 1996. More than 15 000 delegates from all over the world mulled over and discussed the prerequisites for humane living conditions in human settlements taking the varying climatic, topographical and cultural marginal conditions in different regions of the globe into account. Apart from the built-up areas themselves, the utilisation of underground space is experiencing high and ever increasing significance in less densely populated regions. Attractive and fast transport links between industrial centres call for high- performance transport arteries for the economic, speedy and unhampered carriage of people and goods. Important impulses for the economic power of a region or nation are provided by transport development and links. As a consequence, tunnels for roads and railways are being built or planned to a great degree for crossing mountain ranges, rivers and straits.

Jan 1, 1999

By Higuchi K

Intorducing the hypothesis that the cause ,òi spontaneous combustion of coal is depending un the accumulation of heat produced by its oxidation, the authors derived the equation expressing the temperature change in a heap i fine coal. To solve the equation, thermal conductivity, specific heat and rate of heat ,eneration of fine coal (-48 mesh) were measured at various temperatures in the range _'0-65¦C. The equation was solved numerically and the volume of fine coal which would ignite spontaneously was estimated as the function of ambient temperature. Using 170 Kg of fine coal, everal experiments for confirmation were conducted. At the ambient temperatures of 60¦C nd 50¦C, coal began to fire spontaneously brut 00 and 110 hours later respectively. Iii addition to this, the measured t,,rp,i,itures in the coal heap agreed with the ,aLulated ones comparatively well, If more volume of fine coal were used, experi;:ontul ;,eneration of spontaneous combustion from ...,n-, , 1-1 I'd Sill al r..

Jan 1, 1981

Creating Value and Improving Environmental Performance by the Recovery of Valuable Products from Tailings from the Athabasca Oil Sands in Alberta, Canada

Sep 13, 2010

By Ngai WCT

Over 90 per cent of the explosives in Hong Kong are used in civil engineering works. The Hong Kong Government controls all explosives and delivers on a daily basis to each site which it has licensed. Such deliveries need to be arranged the day before actual delivery. With the vagaries of the traffic in Hong Kong, contractors do not necessarily know the time of arrival of explosives. Contractors in general would like to reduce their exposure to these potential delays and the high cost of explosives deliveries. The high population density and urbanisation means that rock blasting has to be carried out in close proximity to other property. In order to protect life, property and utilities, it is not only necessary to employ proper blasting techniques but also to adopt effective safety measures. The Route 3 Advance Earthworks project is located on the north-west corner of Tsing Yi Island, Hong Kong. It is one of the Airport Core Programme projects for the new Chek Lap Kok Airport. Secured by Leighton Contractors (Asia) Ltd in early-1992, the work commenced in May of the same year, with completion and handover to the Hong Kong Government in May 1995.

Jan 1, 1995

By M Barley, C A. RosiFre, L Lobato

The Carajßs iron ore deposits contain approximately 17.5 billion tons of ore with >64 per cent Fe and occur in the eastern part of the Amazonas Craton. They are hosted by jaspilitic banded iron-formation (BIF) of the Carajßs Formation which, together with metavolcanic rocks, comprise the ~2.75Ga Grpo Parß Group of the Itacai·nas Supergroup in the ~1000 km long, E-W trending Carajßs Synclinorium. The Carajas Formation comprises discontinuous layers and lenses of partly dolomitised BIF (17 - 43 per cent Fe and 35 - 61 per cent SiO2) and lenses of high-grade iron ore, cut by mafic sills and dykes. The high-grade iron ores occur as large tabular bodies of friable (soft) hematite with smaller lenses of hard (compact) hematite. The hard hematite ores typically occur at the contact with the underlying volcanic rocks and are surrounded by an aureole of hydrothermal carbonate alteration. BIF that has been overprinted by dolomite and magnetite crystallisation has recently been discovered at depth in the N4E Mine. With increasing amounts of carbonate, the original lamination (microbanding) and other fine primary structures in the BIF have been progressively obliterated resulting in alternating carbonate and iron oxide mesobands. The friable hematite ore that is characteristic of the Carajßs deposits results from ongoing weathering and leaching of the carbonates from this type of altered BIF. The hard hematite ores probably result from more extensive early oxidation. The association of both carbonate-altered and jaspilitic BIF with the N4 Mine is similar to that observed at the Mount Tom Price deposit in Western Australia, where carbonate-altered BIF occurs below massive hematite ore with a jaspilitic halo developed above the orebody. This indicates that as at Mount Tom Price, hydrothermal carbonate alteration and associated loss of silica from BIF may be an important step in the formation of these giant hematite deposits.

Jan 1, 2002

By J de Vries

Arthur Page, a past President of AT&T said:All businesses in a democratic society begin with public permission, and exist by public approval. Product stewardship in its most basic form is simply risk management applied to the products we produce. Conceptually it may be considered as a more expansive approach to many existing safety, heath and environmental programs. Key differences include the extension of responsibility beyond the direct control of management, and consideration of the implications your products and processes have on the broader community, as opposed to the confines of an individual mine site or operation. This paper reviews the processes used by Orica Ltd to manage its product stewardship program. OricaÆs product stewardship program is expansive and supports activities and business that range from manufacture and delivery of commercial explosives and sodium cyanide to mines throughout the world, supply and operation of municipal water facilities, and manufacture and distribution of consumer products such as household paints and adhesives. We highlight the development of the program through experience both good and bad, and by use of case studies to illustrate how an active product stewardship program is an effective business risk mitigation strategy.

Jan 1, 2006

By S Ellis, J McMullen, M Habner

A new leaching regime was implemented at Kalgoorlie Consolidated Gold MinesÆ (KCGM) Gidji plant on a cyanide leach of ultra-fine ground sulfide concentrate. High lime concentration and lead nitrate were used to overcome the refractoriness of the fine sulfides (high reactivity of fine sulfides with the presence of gold tellurides). The leach pretreatment stage was shown to be detrimental and was shut down. Lime titration was introduced as part of the process control. It was shown that the leach could be performed at low dissolved oxygen, (ie 3 - 5 ppm) to avoid sulfide oxidation and the associated high cyanide and lime consumption. Plant results showed reduced cyanide consumption (40 per cent) and an accelerated leaching rate, whereby most of the gold was dissolved in 24 hours compared to 72 hours used previously. Similar work was performed at KCGMÆs Fimiston plant, which leached a combined ultra-fine ground sulfide concentrate along with the slimes fraction from hydrocycloning the bulk flotation concentrate. The use of lead nitrate, high lime and carbon-in-leach generated a faster leaching rate and minimised adsorption of gold on fine pyrite particles. The grind, previously controlled with a P80, was replaced by a P98 to give a better operational indication of top size hydrocyclone performance. Before the implementation of the changes, average leach residues for slimes and UFG were respectively 4.0 g/t and 5.5 g/t. With the modifications to the leaching regime, average leach residues were lower by 1.5 - 2.0 g/t. Whilst significant improvements have been demonstrated, further work is progressing at KCGM to further reduce ultra-fine concentrate leach tail grades, and also to improve the understanding of concentrate refractoriness and the factors responsible for differences between laboratory and plant leach results. Estimated profits since the implementation of the new approach are in the range of $A3.5 million per year.

Jan 1, 2005

Benchmarking of mining operations has been in vogue for a number of years: it seems teams are forever flying around the world to try to understand what other operations are doing. However, unless a benchmarking exercise involves data gathering at a fundamental level and a rigorous analysis process is applied, the trip will be nothing more than industrial tourism. When benchmarking is performed thoroughly, the range of comparisons that can be made is extensive and informative, and need not be restricted to sites with similar conditions and equipment fleets. This paper describes the detailed and rigorous process for benchmarking used throughout AMC benchmarking studies. The paper demonstrates how, through drilling down to the underlying drivers, the often heard cry of æyou canÆt compare us, weÆre differentÆ can be overcome. Included in the discussion are a number of significant issues that have been identified during AMC benchmarking studies. The paper then considers the types of opportunities that have been identified and the potential for improvement. The paper concludes with a discussion of the implications for planning, measuring and management of operational performance.

Jan 1, 2003

By W Lunwongsa, S Meffre, S Nuanla-ong, K Zaw, R James, A Salam

Gold and silver mineralisation at the Chatree low sulfidation deposit is hosted in andesitic volcanic and volcaniclastic rocks and characterised by multiple hydrothermal alteration assemblages and quartz-carbonate (chlorite-adularia) replacements, veins and breccias. The ore-bearing veins are influenced by intersecting structures and host rock lithologies. Emplacement of the host succession occurred at 250 ¦ 6 Ma (dated with laser ablation ICP-MS U-Pb zircon techniques), which was closely followed by mineralisation at 250.9 ¦ 0.8 Ma based on the analysis of adularia from coarse-grained quartz-sulfide (chalcopyrite-pyrite- sphalerite) veins using laser ablation Ar-Ar methods. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By S Januszewski and, G Dirom, D Christensen

Four field test plots were constructed in 1998 on a sloped waste rock surface at the Myra Falls Operations of Boliden Westmin (Canada) Limited to evaluate hydraulic performance of alternate cover system designs. The field test plot cover systems were designed to control oxygen ingress and water infiltration to the underlying waste rock while providing a medium for a grass and legume vegetation cover. The test plots consisted of a bare waste rock surface (control plot), and three additional plots consisting of native compacted till placed directly on the waste rock surface, overlain by non-compacted till. Two of the test plots included a compacted till layer ameliorated with flyash and bentonite, respectively, to improve moisture retention and reduce permeability. The third test plot consisted of a compacted layer of native till overlain by non-compacted till. A performance monitoring system was installed in each test plot to evaluate net percolation and oxygen ingress to the underlying waste rock. In addition, each test plot has profiles of matric suction, water content, and temperature sensors installed at up-slope and down slope locations. A review of four years of monitoring data shows that the compacted till/bentonite cover system has been most successful in limiting the infiltration of meteoric waters and oxygen ingress to the underlying waste rock material. The compacted till/flyash and compacted till cover systems have produced similar net percolation results and neither have functioned well in maintaining an oxygen ingress layer throughout the year. The amelioration of bentonite with till to produce a compacted barrier layer shows promise in reducing water and oxygen ingress at the MFO site, while the incorporation of flyash with the till did not result in a significant increase in performance. The field performance data clearly demonstrates the need for developing field trials prior to full-scale construction, as opposed to relying solely on an un-calibrated numerical modelling to design the full-scale cover system.

Jan 1, 2003

The Australian minerals sector has a shortage of skilled professionals to satisfy an industry that is experiencing renewed vitality. Graduate numbers are low throughout Australia and the world, while economic rationalisation is seeing many educational institutions downsize, or even close, their minerals-related programs. In addition to requiring more entry-level graduates, minerals producers are looking to update the skills of their current workforce to keep up with the industryÆs continuing technological revolution. To address the issue the Minerals Council of Australia (MCA) endorsed collaboration between several Australian minerals producers and a team of universities to generate the Mineral Tertiary Education Council, or MTEC. MTEC recently initiated a venture to increase the availability of professionals with relevant skills to the minerals industry. Primarily aimed at delivering postgraduate programs, the initiative will allow graduates from other disciplines to æconvertÆ to the minerals sector as well as provide professional development training to an existing work force. This venture represents a novel approach in that courses will be delivered by more than one institution and will employ innovative teaching materials with flexible and remote delivery formats. The programs will cater specially for professional development in the minerals sector, which generally requires high flexibility due to the nature of work conditions and locations.

Jan 1, 2004

By Wu H. W, Jones S. J

Australia wide, over 40 fly-in/fly-out mining operations and other forms of long distance commuting now exist, with coverage of about 5000 employees. The substantial majority of these operations are in Western Australia, with some mines also located in Queensland and the Northern Territory. In recent years new large-scale mining operations have adopted the fly-in/fly-out approach and it is important to note that no new mining towns have been constructed in Australia since the township of Roxby Downs was built in the late-1980s to service the Olympic Dam mine. An examination of fly-in/fly-out mining operations in Australia has been undertaken. A detailed survey undertaken in 1990 has been reviewed and another intensive survey undertaken to establish emerging trends. Results from both company and individual employees point of view have been analysed. A section examines the views of professional employees and the influence of fly-in/fly-out on career development. Bus-in/bus-out coal mining operations are emerging in Queensland's Bowen Basin. These operations commute their employees into the mine site for compressed working schedules while the mine employees' families are domiciled in regional cities such as Mackay. A review of the issues associated with the development of long distance commute coal mining operations in Queensland's Bowen Basin is performed and two case studies examined.

Jan 1, 1997

By W Gale

Rock and coal fractures together with micro seismic vibration is a common occurrence during mining, however, it is very uncommon for coal and rock to be propelled into the roadway. Irrespective, such occurrences do occur and appear to require significantly more energy than is available from strain energy release during coal cutting. The sources of energy which can contribute to the propulsion of coal from the face or ribs are typically strain energy from the surrounding ground, seismic energy from a rapid rupture of the ground in the vicinity, or rapid expansion of gas from within the burst source area. The aim of this presentation is to briefly review the mechanics of a coal burst and to discuss the mining situations for which the energy is sufficient to create bursts. A brief discussion of alleviation strategies is discussed. This is an abstract only. No full paper was prepared for this presentation. CITATION:Gale, W, 2018. An overview of coal burst phenomena, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), p 2 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By R. A. Frith, M D. Goodz

Ore-bearing minerals that are located along microfractures are always susceptible to loss during the breakage and sampling of the material. Further losses occur with on-site sample preparation and splitting prior to laboratory analysis. In these cases solid whole rock channel or core samples should be handled with due care to ensure all fines and loose particles are collected and included in the sample for total chemical analysis.Similarly open hole and reverse circulation drill methods are not usable in areas containing old mine workings, heavily fractured ground or highly degraded/oxidised mineral assemblages. Nor are these methods usable to assess a bulk mineable target where the enriched zones were peripheral to or between old mine cavities.

Jan 1, 1993

By P Hanna

In an effort to improve returns to shareholders, the Australian Mining Industry has consolidated considerably over the past decade or so. Technical services at mines have been re-structured, whilst those at corporate offices have been all but eliminated. A recent study of the role of the geologist in BM Alliance Coal Operations Pty Ltd (BMA), showed the adverse impact on the companyÆs performance due to a lack of geologists. With an education campaign, to demonstrate the contribution of geologists to the æbottom lineÆ and in increasing the options available to the company, the value of the geology role became better understood. The implications of the loss of invaluable corporate knowledge, when long serving geologists left the company, also became clear. Steps have since been taken to increase the numbers of company geologists, particularly on mine sites. In common with other sectors of the mining industry, the Australian coal industry is experiencing a critical shortage of experienced coal geologists, as companies have found in recent recruitment efforts. This is further evidence that the recommendations from the recent study by World Competitive Practices, commissioned by The Australasian Institute of Mining and Metallurgy, æRising to the ChallengeÆ have not been adopted. People, and the mineral resource base, are the assets from which mining companies gain a sustainable competitive advantage. Geologists, as the nexus between the resource base and people, are in a unique position to enhance the profitability of their companies. To maximise their contribution to the industry, and ensure that they receive due recognition, geologists must adopt a more commercial approach in their work and take a front foot stance in promoting their value to management. Geology is a core competency for all mining companies. The tendency for companies to outsource this function, to the detriment of the company geologist role, is not sustainable in the longer term. TodayÆs geologists need to work closely with management, technical and human resource professionals, universities and schools to ensure their significant value is well understood, and that the industry can attract, train and retain new recruits through the implementation of graduate programs and company career paths.

Jan 1, 2003