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By B J. Hutchison, S Gannon, J Chambers, D Oko-oboh

The Kanmantoo copper mine is located in the Adelaide Hills area of South Australia and is owned and operated by Hillgrove Resources (HGO). The mine is a drill and blast, truck and shovel operation mining sulfide (chalcopyrite) ore located in chloritised andalusite biotite schist. The initial Kanmantoo open pit operation occurred in the 1970s, before falling copper prices closed the mine. In 2010 the mine was reopened by HGO and the Kavanagh cutback of the Kanmantoo pit was undertaken. The Spitfire, Nugent and Emily Star satellite pits were also mined through to 2015 before the latest steep wall Giant pit design was developed to take mining out to 2019.There are no major fault structures and only two significant shear zone structures exposed in the open pit walls. The main Garnet Andalusite Biotite Schist (GABS) unit is quite competent so the pit designs have therefore mainly been controlled by four distinct joint sets. This paper is a case study on the influence of the joint regime on the wall stability of the main GABS unit and how a better understanding of the joint regime and the use of rock reinforcement has allowed the steep wall design to be adopted.The paper also describes the remote geotechnical mapping and slope monitoring techniques used to manage the rockfall risks associated with the steep walled slope design.CITATION:Hutchison, B J, Chambers, J, Gannon, S and Oko-oboh, D, 2017. Case study of joint structure and the design and performance of open pit walls at the Kanmantoo copper mine, in Proceedings Tenth International Mining Geology Conference 2017, pp 355–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

The history of the discovery and development of the Kambalda nickel orebody. is reviewed and the decision to process the Kambalda concentrates by the Sherritt-Gordon process at Kwinana is discussed. The Kwinana Nickel Refinery is described and the problems encountered in the first year of operation are Outlined.

Jan 1, 1971

Hydraulic backfill is generally retained in slopes using permeable barricades. Mitchell et a! (1975), Mitchell (1992) and Grice (1989) have shown that under normal drainage conditions, barricades experience low levels of loading. Cowling et a! (1988) have also shown that barricades are susceptible to piping failures if excess water has ponded on the upper backfill surface and if leakage of backfill from the barricades has occurred. During 1997, six hydraulic backfill barricades failed in four different Australian mines. Fortunately, in each case, the quantity of backfill slurry released was small, and no injuries to personnel nor damage occurred. Detailed investigation of two of the incidents showed that the primary cause of failure could be attributed to the delivery of excess quantities of transport water from the low-density slurry. For each of the incidents investigated there was evidence of the development of piping failures, which resulted in hydrostatic loading conditions on the barricades from the ponded water on the upper backfill surface. The circular failure surfaces in the barricades were characteristic of the application of point loading Conditions.

Jan 1, 1998

By Savory P. J

Uranium mining operations commenced at Ranger mine site, Jabiru NT Australia in May 1980. The Ranger orebodies, totalling approximately 110 000 tonnes contained U305 had been indicated by airborne radiometric survey in 1969 and confirmed by drilling the following year. Both diamond and percussion drilling methods were used to define the mineralisation and samples were analysed using a combination of radiometric and neutron activation techniques. Ore reserve estimates were calculated from conventional and geostatistical methods, and following the mining of 15 million tonnes of ore, reconciliations with before mining estimates are well within acceptable industry standards. In-pit grade control employs radiometric techniques including a radiometric truck discriminator built in Australia to mine specification to meet production requirements and improve productivity. Environmental requirements associated with uranium mining are a daily consideration.

Jan 1, 1993

I trust you know now or will know by the time you havecompleted your degree and added a little on-the-job experience,how to make the product from the mine you are working for. Butyou may not know the process to turn it into dollars, which ofcourse will be the life blood of your company. I am not going topromise to turn you into super salesmen, but I hope I can takeyou beyond the level of believing that selling our mineralproducts is as simple as putting in it on to a train, waving itgoodbye and waiting for the cheque to turn up in the mailbox afew weeks later.

Jan 1, 1994

By Hebblewhite B, Humphreys D

An experimental mining project has been carried out in the Collie Basin to demonstrate the safe operation of total extraction mining techniques in the underground mines of the basin. To achieve this, it was necessary to design and install a means of controlling or removing groundwater so that goafing of the overlying strata could be safely achieved as part of the mining operation. The site chosen for the experiment was a triangular panel adjacent to Western No 6 (WD6) underground mine, which includes the 3 to 4 m thick Wyvern Seam beneath 130 to 180 m of overburden. The test area abuts a major fault on the downdip side. The overburden and underburden sequences include several horizons of permeable sandstones which form major aquifers. Water problems have long been recognized in all underground mines in the Collie Basin, and have previously prevented the successful application of total extraction mining. Following extensive hydrological investigations, dewatering and depressurization systems were designed to dewater the immediate roof aquifers and to depressurize aquifers higher in the sequence and in the floor. This would enable stable roof conditions to develop and controlled goafing to be achieved. The roof dewatering/depressurization procedure involved a combination of in-mine vertical roof drainage holes and conventional dewatering bores constructed from the ground surface above the mining trial area. The dewatering system was installed and operated for 29 months before the commencement of mining. Mining was eventually successfully completed in two trial panels using a retreat Wongawilli extraction system using bridge conveyors and continuous miners. Water inflow into the mine workings was channelled to a constructed sump area at the lowermost corner of the panel and pumped to the surface via vertical sump bores. The dewatering and depressurization measures adopted were successful in permitting the first controlled and systematic total extraction recovery of coal from the Collie Basin. This trial mining exercise demonstrated the potential for increasing substantially the recovery of coal from the Collie Basin, where previously recovery rates of around 30 percent from underground mining were commonplace, using only bord and pillar methods.

Jan 1, 1988

By M Podreka, P Merry, L van den Berg

Anglo Gold AshantiÆs Sunrise Dam operation is located in Western Australia approximately 55 km south of the town of Laverton. Currently, the mine is producing from both its open pit and underground operations and is planning a significant step change in underground production as the pit phases out. The mine ventilation system is arranged in three independent ventilation districts: Astro, GQ and Cosmo. The future ventilation infrastructure requires significant upgrades to keep up with the increased tonnage. In the short term, increased production is planned for the GQ district as well as for Vogue, which is an extension in the Cosmo ventilation district. In the long term, however, Vogue is likely to become the centre of attention for mining activity.This paper explores several ventilation scenarios which include upgrading the existing fan stations, rentals, establishing a common ventilation backbone, and establishing new upcast infrastructure for GQ to support the short-term production increase. These developments were modelled using ventilation network simulation software to determine airflow distribution and fan operating points for each option. For the GQ area, with its short-term increase in production, each option is evaluated for total owning cost by considering capital and operating costs over a three-year period. For Vogue, which is to become the main focus of mining in the future, a different strategy is followed in analysing the ventilation requirements. Instead of considering different short-term options, a number of staged upgrades are considered to achieve the desired production rates.This paper summarises the planning criteria, airflow requirements, ventilation infrastructure requirements, and economic analysis associated with the conceptual ventilation system design. It highlights how the best short-term ventilation infrastructure upgrades can be selected when considered in isolation but highlights that long-term production planning can have an effect on the decisions made in the short-term.CITATION:van den Berg, L, Podreka, M and Merry, P, 2013. Sunrise Dam short- to long-term ventilation planning, in Proceedings The Australian Mine Ventilation Conference , pp 107-114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By O N. Savassi

A rigorous methodology for prediction of flotation plant performance is presented, which is based on a standardised batch flotation test called the MFT. The work is part of the FLEET program, developed by MinnovEX with the support of seven large mining firms. The methodology is divided into three key steps: direct measurement of the kinetics of true flotation in the pulp, independent of hydraulic entrainment and other froth effects in the batch cell; benchmarking of the industrial plant over a broad range of ore types and operation conditions; and model calibration to describe froth effects in the plant, with a minimal number of parameters. To date, the methodology has been applied with success at several industrial plants, encompassing copper, gold, nickel, iron, lead, zinc and coal operations. This paper includes a description of the laboratory testwork procedure and scale-up to full industrial circuits. Examples of industrial application are also presented.

Jan 1, 2005

By N Van Buc, E Coroiu

The rapid socio-economic growth of Hanoi City coincides with a corresponding growth of the transport demand. Today, the transport in Hanoi is completely dependent on private modes of transport. Because of the lack of an efficient public transport system and the expected rapid increase in traffic volumes, the movement of people and goods in the urban areas of Hanoi will cause congestion in the present city transport network. The solution of the construction of new roads, or the widening of the existing streets, is very expensive in urban areas and usually causes many social problems due to the resettlement of people. From the point of view of the number of inhabitants, Hanoi City is now over one million. Above this number the international experience shows that the public transportation must be a mass transport system with large capacity, commercial speed and also independent as much as possible from the street network. According to the Hanoi Master Plan for 2020, the Hanoi urban population will be over 3.5 million persons. Also, in the next 15 years, the distances between centre-destination points will be doubled by comparison to 1995.

Jan 1, 1999

In terms of tunnelling the mining industry is generally thought of as the crude cousin of the civil construction industry. Mining has tended to concentrate on speed and flexibility rather than the high standards required in civil tunnelling. Historically this difference has been based on the belief that such high standards were not required by the mining industry, they would slow down the development of the project and as a result increase the costs and extend the time period between start up and a positive cashflow.For civil works the construction of a tunnel is the project, for mining the construction of declines, crosscuts and drives are merely the means of accessing the orebody so that the real work can begin û MINING. Extraction of ore is the core business of most mining companies û it is what pays the bills.Though most mining companies have the equipment, the people, the knowledge and the ability to excavate tunnels, in the past mining companies did not appear to put the same energy into their tunnelling operations as they put into improving their ore extraction operations. In the past decade this appears to have changed, many mining companies now realise how important the correct excavation of a decline is to the success of the overall mining operation. They began to recognise that there were cost benefits to be gained in using the correct development techniques without overly sacrificing the benefits of speed and flexibility.This recognition also coincided with the growth of underground contractors whose predominant work was primary development (declines and ore access crosscuts and drives). The contractors again had the same knowledge, the same people, and similar equipment but their focus was different from that of the mining company û the contractors were focused on the development of the mine, the excavation of declines, crosscuts and drives. These deliverables were the contractorsÆ core business û itÆs what paid the bills.

Jan 1, 1999

By A J. Minns

This paper addresses the question: how can the minerals industry remain viable; viable in the sense that we are able to access land for exploration and discovery, we are able to develop and operate mines (and processing plants) safely and profitably and we are able to close operations in a responsible manner, so that modified landscapes are restored to acceptable community standards?Many of the answers to this question can be addressed through the theme of this conference û that of eco-efficiency. The eco-efficiency concept is very useful, since it does help to translate principles of sustainability into business value at the operational level. To provide some context to how this can be achieved, the paper discusses what is happening at the international level, outlines some key industry initiatives within Australia and then discusses what work is being done within companies.

Jan 1, 2004

The King River Power Development on the West Coast of Tasmania has involved the storage of the waters of the King River in the new Lake Burbury and their diversion through a 7 km tunnel to a 144 MW power station. The last kilometre of this tunnel descends through 160 m under a ridge before emerging from the bank of the King River at the power station site. The decreasing cover over the tunnel as it approaches the power station meant that a steel lining was required in the last few hundred metres of the tunnel. This paper describes the geotechnical investigations which were carried out to establish the necessary length of the steel lining.

Jan 1, 1993

By Morris B. J

Soil air samples taken from the top one metre of the soil profile, were measured for C02 and 02 using portable field analysers at a number of sites of known sulphide mineralisation in South Australia. Carbon dioxide anomalies were detected over actively oxidising sulphides during autumn and winter following recent rainfall. Anomalies were not detected where no oxidation was occurring, where seasonal conditions had been very dry, or where the sulphur content of the ore was low (

Jan 1, 1993

By Sarkar B. C, Sen A. K

India is well endowed with vast reserves of banded hematite ore, about 12 billion tonnes, estimated by some conventional methods. Various authors have assessed this huge reserve using some advanced geostatistical methods. A Banded Iron Formation (BIF) belt named the `Singhbhum-Keonjhar-Bonai' belt in India has been chosen as a case study. In this paper, the experiences of Chiria iron ore, in particular, have been described. This study will finally create a dynamic mineral inventory after standardising the geostatistical parameters which will help to cater for the needs of the stringent quality requirements of the Indian steel industries.

Jan 1, 1995

By H S. Smit, P Lotz

Gold mining companies who are signatories of the International Cyanide Management Code (visit www.cyanidecode.org for further information) are required to measure WAD cyanide on-line and destroy WAD cyanide in excess of specified limits. Weak acid dissociable (WAD) cyanide refers to those cyanide species liberated at a moderate pH of 4.5 such as HCN(aq) and CN-, and the majority of Zn, Cd, Cu, Ni and Ag complexes with low dissociation constants. It is potentially toxic to humans and animals. Recognising and in response to the gold mining industryÆs need for an on-line WAD cyanide measurement device, Mintek recently developed the WAD Cynoprobe. The WAD cyanide analysis technique is based on the use of a ligand exchange reagent that liberates WAD cyanide from metal-cyano complexes. The ligand exchange reaction is represented by the following chemical equation: Metal(CN)X + yLigand <-> Metal(Ligand)y + xCN- The plant filtrate is treated with a ligand exchange reagent, to liberate WAD cyanide, before measuring the free cyanide concentration via amperometry. The instrument proved to be accurate and reliable in the laboratory as well as under industrial gold plant conditions during various trials. It has gained wide-spread commercial acceptance both locally and internationally. However, itÆs recent exposure to complex ore types have called for refinements to the analysis technique. It has been further developed to improve its precision and accuracy and to remove reagent and thiosulfate interferences. Its compatibility with the most commonly used destruction oxidants has also recently been investigated. The WAD Cynoprobe may be configured to measure both free and WAD cyanide concentration. Its fast analysis time, approximately 5 min, makes it suitable for use in the control and optimisation of the cyanide destruction and recovery process. Proper oxidant dosage control and monitoring of effluent concentration levels will ultimately result in less cyanide and post-destruction salts discharged into the environment.

Jan 1, 2008

Crandallite and millisite in Christmas Island 'B' and 'C' phosphate ores are rapidly decomposed by sodium hydroxide solutions at about 80QC. As these phosphates generally contain less than 1% silica, an alkaline extraction process can be designed, in which up to 95% of the sodium hydroxide used, may be recycled. The insoluble residue consists of an impure, highly reactive apatite, which in pot trials, has given good responses as a direct application fertiliser; alternatively this residue can be underacidulated to give a granular product with fertiliser potential. The hot leaching solution contains up to 95% of the alumina and approx- imately half of the phosphate from the original ore. Simple crystallising techniques have been developed on a laboratory-scale to use this leaching solution for producing smelter-grade alumina and detergent-quality trisodium phosphate. As the demand for detergents is limited, an investigation was made of the reaction between trisodium phosphate and slaked lime, derived from a high-grade New Zealand limestone occurring near Oamaru. The product is calcium phosphate, containing up to 40% P205, and less than 0.2% each of iron, aluminium and fluorine, and it should be a useful raw material for phosphoric acid manufacture. A preliminary economic evaluation of the whole process looks promising, And warrants further investigations, including pilot-plant work.

Jan 1, 1971

By X Li, W McKeague, M S. Powell

This paper explores the importance of operators in the overall efficiency of mineral processing plants. With the potential of future control configurations becoming more remote, it is time to review the implementation of control and utilisation of operators. This paper is based on a preliminary review of operators and control room operations and clearly shows that, in the minerals industry, operations are typically run in a reactive mode (with a focus on ensuring equipment operation), rather than in a proactive mode (with a focus on optimising the process performance). The primary reason for this misguided approach is the short sighted thinking applied to the challenges of designing technology and organisational tools capable of addressing the essential operational needs: an approach which inevitably results in a disconnect between people and technology. Contrary to the popular approach of replacing operators with expert systems, the thesis of this paper is that the shift to more complex circuits, with higher demands on processing capability and control, will require the actual upskilling of operators. Experience in mineral processing and other industries indicates that expert systems cope well with small changes but are typically unable to respond to major changes in feed material and this is where the expert operator becomes crucial. Providing operators with ongoing high level training in process understanding, and restructuring how they interact with the plant and interface with the control system is the approach being proposed here - an approach surprisingly underutilised and often absent in the minerals industry today.CITATION:Li, X, Powell, M S and McKeague, W, 2012. Unlocking processing potential by empowering our operators, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 333-340 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By H Rossiter, A Maddever, J Market, P Jeanneau, A Virani

It is generally acknowledged that the head grade of the world’s copper resources is declining. Accordingly, there is an increase in the volume of resource material being mined and processed to maintain copper production. This has led to increases in cost base accompanied by reductions in Life of Mine (LOM) Net Present Value (NPV). The higher tonnages of material mined are driven by increased quantities of lower grade material required to satisfy the short term mine model. In turn, this has brought an increased focus on sampling and assay methods, since any error associated with estimating the grade of each block and determining its correct destination serves to magnify the losses that will occur. Presently most open-pit copper mining operations use blasthole sample assays to feed their shortterm model. The problematic nature of blasthole sampling is well documented (Engström, 2017), particularly the poor timeliness of the data and the significant errors that are inherent to the technique. Methods to improve grade control, such as drilling a separate grade control grid, have been proposed but come with their own cost, logistical, and accuracy shortcomings. A recent development in grade estimation is the Pulsed Fast and Thermal Neutron Activation (PFTNA) downhole logging probe. Deployed on an efficient semi-autonomous platform, PFTNA is being aggressively adopted in the Australian iron ore industry. The technology provides in-situ elemental analysis of the geological formation, delivering high accuracy, high efficiency, near realtime data from a sizeable measurement volume. In this paper we consider the application of the technology to copper. Whilst there are several operational components to such a value proposition, we focus on the benefits of improved gradeestimation. A simulated copper mine is used to model the quantum of improvement expected from a reduced grade-estimation error, which reduces the likelihood of misallocating material to the wrong destination, which in turn increases NPV.

Nov 10, 2020

By A Roseman, T Gruber

Traditional methods for installing gaskets for segmented bored tunnels have relied upon different bonding procedures with adhesives that carry a series of disadvantages to segment producers. Fixation of the gaskets into the concrete segment as part of the casting procedure has been developed over the last 20 years and has emerged as an economical solution to produce high-quality tunnel segments for various technical tunnel applications. This paper investigates the advantages of using anchored gaskets, the different tunnel systems that employ anchor gaskets and reviews the first anchor gasket project; the Lee Tunnel and analyses how segment production efficiencies are gained.CITATION:Gruber, T and Roseman, A, 2014. Use of anchored gaskets in segmented bored tunnels, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 253–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

In the first half of 1987 two four metre diameter raise bore holes were drilled at the Olympic Dam Project for ventilation purposes. The first hole, 476 m x 4.0 m diameter was completed in 96 days, 35 days longer than scheduled. The second hole, 407 m x 4.0 m diameter was completed in 39 days, 2 days ahead of schedule. Both holes were drilled with a Robbins 121R rig using a Wirth head that consisted of 23 face cutters and 5 side cutters, supplied by a contractor. After the sites were located a grouting program was carried out to help seal off an aquifer between 160 and 180 m below the surface. Cavities discovered in the Andamooka Limestone were filled with concrete. Because of the overlying dune sands and clay both sites were pre-sunk to the competent Andamooka Limestone.

Jan 1, 1988