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This paper cites selected, prominent examples of current, major projects in Southern Africa in both the mining and civil fields. Differences and similarities in the life cycle of mining and civil projects are discussed. A closer relationship between the mining and civil fraternities is beginning to develop and should be encouraged because of the resultant exchange of experience and technology which benefits both disciplines. An attempt is made to assess future potential for new, major projects and trends in the implementation thereof.

Jan 1, 1999

It is no longer adequate when starting a new mine to simply select the best equipment. Today's competitive international commodity markets demand superior efficiency which requires systematic involvement of people in continual improvement of production and commercial processes. True Total Quality of Management (True TQM) principles provide an operating philosophy for maximising productivity and minimising unit costs of output. The presentation will show the practical and successful use of these principles. This paper will introduce the case study and provide background material on True TQM.

Jan 1, 1995

By X S. Li

The modern mechanical excavation machines have enough power for cutting hard rock. The ‘bottle neck’ which limits the use of machines for hard rock excavation is ‘cutting tool’. To cut hard and abrasive rock, CSIRO has been developing Super Material Abrasive Resistant Tools (SMART*CUT). SMART*CUT technology replaces the tungsten carbide (WC) tip of conventional pick with thermally stable diamond composite (TSDC) and attaches the TSDC tip to steel tool body with CSIRO worldwide patented bonding technology. This paper introduces the key features of SMART*CUT, compares its performance with conventional WC tipped tools, discusses the challenges faced by SMART*CUT and the further developments needed for successful application of SMART*CUT to mining industries.

Nov 22, 2011

By H Asche

The Melbourne Metro project has evolved from the Victorian Transport Plan. MM1 is the second major phase of the proposed separation of Melbourne’s radial railway system, creating a line that will operate independently across the metropolitan region. The central section will run beneath the inner suburbs and the central city. The initial project comprises nearly 8 km of twin bore tunnels, three cavern stations and two cut and cover stations, as well as a dive structure and connections with the existing rail system. This paper describes the development of the geological model, a modification of the rock mass classification system derived during the EastLink project and the influence of the geology on the design of the tunnels and stations for the Department of Transport’s business case.The majority of the tunnelling will be in the siltstone and sandstone bedrock. This material has been extensively folded, sheared and intersected by igneous intrusions. A revised rock mass classification system has been developed for the Melbourne Formation to assist in identifying the important engineering properties of the rock and to rationalise the support types required.The Metro’s tunnel alignment crosses the Yarra Delta deposits in the lower reaches of the Moonee Ponds Creek and again at the Yarra itself near Princes Bridge. These deposits vary in extent and thickness over very short distances. The investigation of these materials has been carried out using conventional drilling techniques in conjunction with sonic drilling methods.Over the central section of the Metro, the positions of the new station are determined largely by transport planning requirements and urban development opportunities. However, the stations, and the tunnels, have been the subject of studies, optimising exercises, and selection processes to arrive at the concept design. This paper describes the influence of the varied geology on the development of the design, and the identification and management of the risks in tunnelling under the centre of Melbourne.

Mar 8, 2011

By P Louden, C Rothnie, G Showers

Tiwest employs several methods to assess the quality of heavy mineral concentrates in ore and process samples. Mineralogy is determined using a method called MA98, developed in conjunction with JKMRC over the last three years (Zhang and Whiten, 2001). A range of other techniques are also used to characterise ore, heavy mineral concentrates and mineral products. MA98 is the culmination of efforts since 1989 to determine mineralogy from chemical analysis without recourse to heavy liquid fractionation, which has traditionally been used to discriminate between light-heavy , zircon, rutile and leucoxene. The major advance with MA98 is the use of statistical mass balancing for all chemical species, as opposed to reliance on key chemical species for each mineral. Three magnetic fractions are analysed by X-ray fluorescence spectrometry, with a minerals balance performed for each. Heavy mineral concentrates processed by this method include drill samples, process samples from the wet concentrators and Dry Mill, and mineral products. TBE can be avoided for higher heavy mineral grade samples since quartz is determined from SiO2 balance. In this sense the method is sufficiently universal and robust to cope with a wide range of sample types and compositions. The MA98 algorithm provides abundant information in addition to mineralogy, including TiO2 and Fe2O3 grades of ilmenite and leucoxene, and concentrations of weakly magnetic zircon and kyanite. Information such as this is invaluable in tracking different minerals through the processing plants. Other ore assessment procedures used by Tiwest provide for modelling of orebodies by mineral sizings, Fe in zircon, and FeO and U+Th in ilmenite. Microscopy is used to provide important qualitative information such as grain shape, surface staining and degree of cementing. These quality measurements are included with mineralogy in geological ore models and are available for mine scheduling. In using the above methods to characterise heavy mineral concentrates, Tiwest is better placed to predict and monitor plant performance and product quality from any ore zone.

Jan 1, 2001

By S Harvey

An inrush of water or mud into an underground mine, or sudden subsidence above mining voids represent low probability but high impact risks in underground mining. About two such incidents involving multiple fatalities or loss of production are reported each year worldwide. On average, Australia experiences one such incident every three to four years. This paper reports the development of a Standard that is intended to eliminate fatalities due to inrushes and subsidence.

Jan 1, 1998

By J Isles, S King, A Valenza, R Lawolo, J Evert

PT Nusa Halmahera Minerals (PT NHM) is an Indonesian joint venture company owned by a subsidiary of Newcrest Mining Limited (75 per cent) and PT Aneka Tambang (Persero) (25 per cent). PT NHM operates two underground gold mines, Kencana and Toguraci at the Gosowong mine site in North Halmahera District, North Maluku Province, Indonesia.The Toguraci underground mine development commenced in 2011 with ore production commencing in 2012. Water temperatures ranging from 50°C to 80°C were encountered in the Toguraci open pit associated with the structures containing the gold bearing veins and are believed to be fed from a relic volcanic system one to two kilometres below the mine. Underground development and production has continued to intersect these structures with the result that an integrated programme of geological, hydrogeological modelling and operational project work has been required to dewater the mine ahead of the descending stoping fronts.This paper will detail these programmes.CITATION:Lawolo, R, Isles, J, Evert, J, Valenza, A and King, S, 2017. Hot water management at PT Nusa Halmahera Minerals’ Toguraci Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Morley C

The Mount Charlotte gold mine is located 0.75 km east of the General Post Office in Hannan Street, Kalgoorlie WA and about 3.5 km north of the Fimiston Operations on the famous Golden Mile.Mechanised underground bulk-mining at Mount Charlotte has been in continuous operation since 1963. For the 30-year period ending December 1992, the mine produced 22 million tonnes (Mt) of ore for a recovery of 2.73 million ounces. During 1991/92, the mine produced 1.53 Mt of ore at a head grade of 3.15 gramshonne (g/t) for a recovery of 135 822 ounces.The principal ore source at Mount Charlotte has been the Charlotte Orebody which is now largely mined out. Since 1990, approximately 75 per cent of production has been sourced from the Reward Orebodies. The Charlotte Orebody was a relatively homogeneous quartz stockwork with simple geometry and average bulked grades in the range of 4.0 to 5.5 g/t. This is in contrast to the Reward Orebodies and the more recently defined Charlotte Deeps and Maritana Stockworks, which have complex grade distribution and geometry with lower average bulked grades (2 to 4 g/t). The lower grades are principally due to the decreased density and volume of stockwork venation and related vein halo alteration. Typically, these stockworks comprise a patchy mosaic of quartz veins and vein swarms, with irregular distribution and geometry within the quartz gabbro host rock.

Jan 1, 1993

By M Sandy, A Vakili, J Albrecht

Although rock strength anisotropy is a well-known phenomenon in rock mechanics, its impact on geotechnical design is often ignored. No widely accepted guideline currently exists for its characterisation. Anisotropy can significantly control the failure mechanism and progression of damage into the rock mass, particularly in high-stress conditions. As such, it can play a key role in the stability of underground excavations and subsequent geotechnical design.This paper introduces the concept of anisotropy at both intact and rock mass scales. It then presents guidelines for measuring anisotropy and assigning rock mass strength properties. An improved unified constitutive model (IUCM), which can account for more complex failure mechanisms, is then briefly described. This IUCM is used to better understand the typical responses of anisotropic rocks to underground mining and to develop an improved damage classification scheme for these conditions.The application of conventional design methods in anisotropic conditions is shown to lead to significant errors. Two case histories are then presented, illustrating how the proposed methodology can improve the reliability and accuracy of the geotechnical analysis when compared with conventional design methods.CITATION:Vakili, A, Albrecht, J and Sandy, M, 2014. Rock strength anisotropy and its importance in underground geotechnical design, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 167–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By A G. Shellsh, R J. Henham, J R. Foley

The Porgera Gold Mine, west of Mt Hagen in PNG is a large open pit and underground operation currently producing gold at the rate of almost one million ounces per year. This deposit has produced some 8.8 million ounces to-date and has current reserves of 103.4 million tonnes @3.2 g/t Au. The Porgera Joint Venture has invested over $A1 billion in infrastructure in this project. Technical management of this operation involves the interrogation of some 700 000 metres of diamond drilling, some 50 000 blastholes per year, and very large volumes of laboratory, geotechnical, environmental and production reporting data. Over the past seven years this data has been consolidated into a single centralised, relational database which now acts as the single reference point for all the technical application systems used for surveying, grade control, production reporting, deposit evaluation and modelling. Data transfer to application programs and management systems is controlled by the centralised database, this process at times involving a two-way, real-time, binary data transfer. The benefits of a specialised database application include security and integrity of the data asset, ease of access, and performance in a multi-user environment. This replaced fragmented, inconsistent data sets stored inefficiently as individual, unindexed, variably formatted files associated with the different application programs. Most importantly, the database has allowed mine management at all levels to make timely, confident investment, cash flow and optimisation decisions as it provides the primary link between the deposit and operational data sets on one hand, and the application programs and management and performance measurement systems on the other. This paper discusses the economic value and importance of technical data in terms of the resource asset and the means by which this data is being managed and used at Porgera.

Jan 1, 2000

By M Bouare, C Holland, K N’Diaye

Two adjacent open pits in Mali hosted by deeply weathered saprolitic materials were mined consecutively over the course of approximately 12 months. During excavation, both pits experienced significant displacement and tension cracking as the result of deeper than expected depth of weathering coupled with relatively steep slope angles and significant groundwater. In response, geotechnical and operations teams overcame numerous monitoring challenges with prisms and radar to develop a simple and effective monitoring system coupled to a Trigger Action Response Plan (TARP) which enabled continued safe operations while reducing ore loss. Observations of previous slope performance of these two pits allowed for greater confidence in empirical failure runout calculations that was used to specify the standoff widths for the exclusion zones in the pit. Back analysis of the slope as-built performance after the first indications of slope distress was also conducted. The back analysis was used to confirm rock mass parameters for modelling while being utilised as a reality check for the stability analysis. The stability analysis indicated that leaving a large step-out or buttress would not prevent the displacement, resulting in some ore being sacrificed to ensure the safety of personnel. Key learnings from this experience highlight the importance of: • up-to-date geological interpretation of the depth of weathering • ensuring slope design guidance is reviewed and updated as latest information (ie geology and monitoring) is received • having multiple complementary slope monitoring methods to ensure redundancy • ensuring visual observations and as-built performance are utilised as a reality check to provide greater confidence in stability analysis and design guidance.

Jun 22, 2022

The Mt Keith Mining Alliance operates a fleet of large capacity hydraulic face shovels and more than 40 X 240 t capacity haul trucks to deliver annual production in excess of 40 Mbcm per annum. The Mt Keith Nickel mine is currently operating at a depth to 300 m below surface with a planned final depth of the order of 500 m. As is the case with any large open pit managing the health of the workforce on continuous shift operations is of critical importance to achieving outstanding safety and production outcomes. Fatigue management at Mt Keith is effectively managed by the personnel operating the mining equipment, with assistance and understanding of the management team and supervisors. The program has been driven through the introduction of Fatigue Champions and a comprehensive management plan that includes education, individual health plans and the use of new technologies. Mt Keith has been instrumental in trialling new technology which assists in monitoring fatigue in operations personnel. Insight into these developments is provided in the context of the overall fatigue management plan. The field trials of the OptAlert(TM) system and how it assists in measuring fatigue is explained. The implications for individual operators and the context for a fleet wide approach to fatigue management is also discussed. Mt Keith has recently completed the second phase of trials with the result that this new and exciting technology is being considered for adoption globally across BHP BillitonÆs open pit mining operations.

Jan 1, 2007

By D Van Doorselaere

The purpose of blasting during mining is to produce a muck pile that can be efficiently loaded and transported. There is an increasing awareness of the variation in muck pile characteristics and its economic implications. It is well known that good fragmentation by itself is not sufficient to optimise the muck loading efficiency. The swelling and configuration of the muck pile also significantly affect the productivity of the loading equipment. The characteristics of a muck pile depend upon the blast design parameters, explosive properties and rock mass geology. This study has focused on the dependence of muck pile configuration on blast design parameters, explosive properties and size distribution of the muck.The field work was done in two phases. In the first phase 12 blasts were monitored, while in the second, three blasts were monitored. The blast design parameters and explosive properties for each blast were documented and the following muck pile characteristics were measured:muck pile height and its distance from the facedistance of throwwidth of the power troughsize distribution by image analysis technique.The effects of burden, bench height, heave energy of explosive, row-to-row delay, powder factor and the mean particle size of the fragments on muck pile configuration were examined. It was observed that muck pile height and distance of throw are strongly influenced by the burden, bench height, heave energy of the explosive and the size distribution of the muck. The width of the power trough depends upon the row-to-row delay, powder factor and total burden. In addition, the effect of the fragment size distribution on the muck pile parameters has also been discussed.CITATION:Singh, S P and Van Doorselaere, D, 2015. The relationship between blasting parameters and muck pile configuration, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 369–374 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By A Hilli, K Kosmara, J Steyn

PT Nusa Halmahera Minerals (PT NHM) is an Indonesian joint venture company owned by Newcrest Mining Limited (75 per cent) and PT Aneka Tambang (Persero) (25 per cent). PT NHM operates two underground gold mines, Kencana and Toguraci at the Gosowong mine site in North Halmahera District, North Maluku Province, Indonesia.On 8 February 2016, a major ground movement occurred in the K-Link orebody of the Kencana underground mine, effectively blocking the only two access ways to the stoping area. Following mine clearance, it was found that a Solo production drill rig operator, who had been drilling in the Level 10 Extraction Drive was still underground, cut off from the rest of the mine by the ground movement.Communication, nutritional and logistic supply to the trapped operator was established with the breakthrough of two diamond drill holes. A range of technical expertise and opinions from both on and off-site were sought and two options were chosen for implementation of the rescue operation. The rescue was completed successfully on 16 February 2016 with the operator being rescued in good physical and mental health.CITATION:Kosmara, K, Hilli, A and Steyn, J, 2017. Eight days entrapped – PT Nusa Halmahera Mineral’s rescue of a trapped miner, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By R Moller

Reconciliation at large iron ore operations is a complex and time- consuming process. Often the volume of data and the large range of different stakeholders makes the process almost impossible. Up until recently geologists and engineers at these operations would spend hours cutting and pasting data in and out of monster spreadsheets, diligently comparing how resource/reserve models, grade control and survey pick-ups compare to what was actually produced. In 2003 the Sishen Iron Ore Mine in South Africa broke this cycle by implementing SnowdenÆs Reconcilor software. The implementation of a dedicated reconciliation system required a number of existing practices to be changed, with the involvement of stakeholders right across the mine. Data sources had to be clarified and validated, terminology had to be standardised, processes needed to be documented and some methodologies needed to be updated. This was a task that required significant effort by Kumba personnel so that the system could be successfully implemented. This paper provides a case study of the reconciliation system implementation at Sishen. It is a story of an operation that evolved from using a number of fragmented reconciliation processes to using a unified automated system. This paper outlines the key estimates and measurements that are used for reconciliation, details the characteristics of an automated web-based information management system to facilitate the process and provides some insights about the benefits that have been gained though the use of a rigorous reconciliation process.

Jan 1, 2005

By R Knight

The spatial variability of geometallurgical characteristics in a mineral deposit can have significant impact on financial and mine planning, mineral processing, concentrate quality and tailings composition throughout the life of a project. These characteristics that may determine the success of a project are not readily apparent to geologists unless they are integrated with deposit geology and assay data, modelled in 3D and incorporated into resource block models.One of the primary objectives of geometallurgy is to integrate and incorporate various geologic, geotechnical and geometallurgical parameters into resource block models, which typically are limited to in situ tonnes and grade of economic metals. Critical attributes, such as concentration of deleterious elements that affect the project viability need to be identified and integrated into the resource block model early in the exploration stage to predict project profitability and address potential environmental impacts.Using data from a volcanogenic massive sulfide deposit we present an example of the integration of ore geochemistry (cadmium, arsenic and antimony) with the results of preliminary, bench-scale metallurgical test work in a 3D geometallurgical model that predicts subdomains of poor-quality concentrate and tailings containing environmentally-sensitive elements. This critical information was incorporated into the existing resource block model in order to inform both financial modelling and mine planning.This example demonstrates that geometallurgical data can be effectively integrated with geological and assay data using Leapfrog MiningTM software (Leapfrog Mining) early in the exploration stage of a project. Three-dimensional representations of geometallurgical data can be created directly using primary additive data, as well as from proxies of non-additive parameters. Resource block models can be updated continually with new information as the project passes from exploration through production. In addition, the software allows for 3D visualisation of the characteristics of the materials that will eventually constitute the mill concentrate, tailings, and waste. This study emphasises the critical importance of establishing a systematic geometallurgical approach early in the exploration stage that can be continuously updated with new information throughout the life of the project. In the example that we present, sulfide ore that had otherwise been identified as high-value (in the absence of geochemical and metallurgical data) turns out to be low-value ore due to concentrate penalties and increased environmental impact.

Sep 5, 2011

By A J. Ryan

The Ernest Henry copper-gold Mineral Resource is the major asset heldby Ernest Henry Mining Pty Ltd, comprising A$6.4 billion of containedmetal. The case history presented below describing the evolution andevaluation of this resource generally observes best industry practice and is a good example of effective due diligence in the resource delineation and estimation process. Early reconciliation data from mine production confirms the accuracy and validity of the resource estimate, providing valuable assurance to the mine owners.

Jan 1, 1998

By D McKeon

In July 2006, ten Mining Engineering students and Associate Professor David Laurence from the University of New South Wales (UNSW) participated in the universityÆs inaugural overseas mining field trip. The ten-day trip to western Canada involved visits to two mines in British Columbia, the Diavik Diamond Mine in the Northwest Territories and the Syncrude oil sands operation in Alberta. Importantly, the groupÆs main objective was to gain a global understanding of todayÆs mining industry by observing the different cultural, legal, social and environmental setting found in Canada. It should be noted that the entire trip was planned, organised and directed by the students and benefited from extensive industry support both in Australia and Canada. This report intends to provide an overview of the field trip and describe to a limited extent the Canadian approach to mining.

Jan 1, 2007

By Will D. P

A 328 m, 2.4 m diameter raise-bored shaft has been equipped with a modular ladderway system to provide a second means of egress from Aberfoyle's Hellyer Mine in Tasmania. The modular ladderway consists of platforms, ladders and service pipes assembled at the surface and progressively lowered down the shaft. This system provides a rapid, safe and economical non-entry approach to equipping a shaft. The modular construction and single suspension allows for future extension or for reuse in another shaft.

Jan 1, 1988

By S Saydam

Professional engineers need to be able to apply university learning to practice. In particular, they have to take responsibility for interactions between technical systems and the complex social environments in which they operate. The most effective way of building this competency is through active experiential learning. We have been developing an advanced educational integrated simulation system to provide mining engineering students with an interactive and immersive learning experience that is not otherwise possible. This will give students an authentic experience in working with industry software packages, while also contextualising the learning in terms of the broader and longer-term impact of technical decisions. We have been piloting the system, in undergraduate courses in order to establish its effectiveness in building systems thinking competencies for mining engineering. For postgraduate students and professionals, the same tools and methods can support studies of more challenging and complex scenarios where mining engineers have to place their decisions within complex global industry contexts.

Nov 22, 2011