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By A Simmons, R Longey, D Brett

The South Deposit Tailings Storage Facility (SDTSF), located at Grange Resources Pty Ltd’s (Grange) Savage River mine in north west Tasmania, has recently begun construction. The facility will provide storage for approximately 37 million cubic metres of tailings, equating to approximately 20 years’ tailings storage.The SDTSF embankment will be constructed entirely out of waste rock won from mining operations, and will feature a flow-through drain constructed from alkaline, non-acid forming (NAF) waste rock. This provides Grange with an economical storage solution for waste management (both tailings and waste rock) and maximises available space on site. The outflows discharged through the alkaline rock ‘flow-through’ will provide a long-term source of alkalinity to Main Creek, subsequently feeding into Savage River. This will provide environmental benefits to the downstream ecology that has long been degraded due to the effects of legacy acid and metalliferous drainage (AMD), caused by historical mining operations.CITATION:Longey, R, Brett, D and Simmons, A, 2015. Integrated mine waste management – South Deposit Tailings Storage Facility, Savage River mine, Tasmania, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 343–352 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By D Connelly

Silver and gold bearing ore from the Troy Resources NL Casposo Gold-Silver Project, located within the San Juan Province of Argentina contains a complex mix of gold, silver, electrum and silver sulphides in the ore. Casposo is a typical low sulphidation epithermal style gold–silver deposit where mineralisation is hosted within rhyolite – andesite flows and breccias. Veins are typically banded quartz–chalcedony colloform - crustiform banded with quartz - carbonate infill. Mineralisation is associated with an assemblage consisting of quartz, chalcedony, adularia, calcite, illite, sericite and trace sulphides. Gold and silver occur as electrum, native silver, sulfosalts and silver sulphides. This paper presents a case study that describes the process selection, development and engineering of a tailored process plant for the recovery of gold and silver from this ore.The original feasibility study, modelling, metallurgical testwork and engineering studies are outlined. The final flowsheet was based on minimising capital cost, operability, recovery and minimising technical risk.The process flowsheet uses the traditional Merrill Crowe route because of the high silver to gold ratio in the feed and achieves maximum gold and silver recovery while providing a common facility for future ore body treatment.

Aug 8, 2011

By I Sherrell, R Jain

Worldwide iron ore feed grades are trending downwards and will continue to do so with the increasing difficulties of upgrading ores. This has led to operations looking for ways to capture current tailings that still contain valuable material. In the past, these were acceptable to dispose of, but this practice is no longer economically feasible. With the increasing trend of re-mining previous tailings deposits that could be decades old, new equipment designs have been introduced to upgrade current or historic beneficiation plants. These designs can effectively upgrade these tailings to saleable products.Outotec conducted test programs for upgrading iron ore tailings from flotation rejects, thickener underflow or tailings dumps on samples provided by customers around the globe. The studies utilised Outotec’s SLon vertically pulsating high-gradient magnetic separator in combination with preprocessing equipment such as low-intensity magnetic separation, screen or scrubber and flotation for downstream processing of the magnetic concentrate. A review of the equipment required to economically process these tailings is provided, along with testing data and industrial implementation examples. The effect of different operational and design parameters on Fe grade and recovery from processing each tailings sample has been highlighted.CITATION:Jain, R and Sherrell, I, 2015. Iron ore tailings reprocessing to maximise ore production, in Proceedings Iron Ore 2015, pp 149–158 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By M Morey

Ok Tedi Mine is located eighteen kilometers from the Irian Jaya border in the Star Mountains, Western Province, Papua New Guinea. Sequential flotation concentrators produce a copper / gold concentrate for market, and a pyrite concentrate for environmental containment, with low sulphur tailings from the pyrite flotation sequence being discharged to river. Strict sulphur assay targets are set for the riverine discharge. Current porphyry and skarn ore blends from open pit operations at Mt. Fubilan will cease by 2017. However, drill cores indicate an economic ore body in the skarn ores surrounding and below the current pit limits. With proposed mining from a western pit wall ‘cut back’ and an eastern pit wall underground operation, potential for ore ageing in sub level cave underground stockpiles is apparent. With little information in the literature, Ore Ageing test work at prefeasibility level consisted of multiple one tonne stockpiles of -50 mm crushed rock. For the bankable feasibility study, a successful test work program was implemented utilizing 40 tonne ROM ore stockpiles composed of exposed pit extensions of future ores. Realistic ageing profiles of Skarn ores were obtained from one tonne monthly samples subjected to laboratory testing. Test work outcomes included:• Similar ore ageing profiles from both the pre feasibility study (PFS) and feasibility study (FS) programs, suggesting ore susceptibility to oxidation has greater effect in ore ageing than rock size for Ok Tedi skarns. • Laboratory rougher flotation of pyrite showed significant variation in sulphur recovery rate, suggesting three classes of pyrite floatability.• Laboratory rougher flotation of both copper and pyrite for up to 19 months ore ageing from 11 stockpiles, suggested three stages in the ore ageing process.

Aug 8, 2011

Over the longer term, the adoption of new technology is an essential component in the endless tasks of reducing mining costs, improving safety and improving environmental standards. However the choice of which of the many available new technologies to adopt and which not to adopt is not easy and the price of mistakes can be very high. The most important issue for mine developers faced with making such choices is knowing whether or not a new technology has been developed to the stage where the timing is right for its adoption. A system for categorising new mining technologies is provided. It provides a basis for more easily reaching common understandings about various new technologies and the background information supplied provides an understanding of what it takes to get new technologies to the proven stage and the risks of never getting there. Wherever possible, new full-scale mine developments should not rely on unproven technologies. Approaches to handling situations where a proposed new mine development is not feasible on the basis of proven technologies are also provided. If any commitment to the use of unproven technologies is made, a guarantee of high quality development support from the supplier of that technology is essential. Several case studies of successful and unsuccessful new technology development programs at BHP are Provided.

Jan 1, 1997

By R Small, S Combrinck, R Lindsay

Maintaining your competitive edge in the growing Australian mining sector today is an arduous task. With an ever increasing demand to extract more ore, safely, complete visibility throughout the blasting cycle has become vital to any operation. To achieve this requires full two way communication with every detonator during the testing and programming cycle, as well as, inside the firing window. Concerned with an increase in the number of incidents involving mining equipment, uncovering and digging into unknown misfires on-sites across Australia, Black Star Mine made the decision to embark on the use of electronic detonators to eliminate this hazard. With this safety goal achieved, the mine set about using the added benefits of electronic detonators to improve their drill and blast processes with impressive results.CITATION:Combrinck, S, Lindsay, R and Small, R, 2012. Eliminating unidentified misfires at Xstrata ZincÆs open pits through the application of electronic detonators, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 27-30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By N McKenzie, E Taylor, S V. L Barrett, H Lagger, A Purwodihardjo

This paper discusses the temporary support design methodology for the largest road caverns ever built in Australia—the Lutwyche Caverns—part of the Airport Link project in Brisbane, Australia. The Lutwyche Caverns with a maximum excavated span of 27 m form a key component of this major road project, allowing on and off ramps merging with the underground highway. In addition to the two large span caverns, a 15 m soft ground tunnel with 5 m cover above the caverns and two 24 m deep burial chambers for the 12.4 m tunnel boring machines (TBMs) had to be built in record time at Lutwyche.The temporary support design methodology involved the use of a range of analytical approaches, including empirical methods to provide a starting point for design development, key block models to determine the potential influence of discontinuities on excavation stability and 2/3D continuum and discontinuum models to determine the potential influence of adjacent excavations and the proposed construction staging on the design. In addition, probabilistic analysis of potential kinematic instability using a discrete fracture network (DFN) approach was also undertaken to establish the critical block loads for the temporary lining, while the continuum and discontinuum models were used to design the support for the 1.5 m diameter rock pillar at the north end of the northbound cavern.The numerical modelling was undertaken in close conjunction with the contractor to develop the optimal construction sequence, considering the available construction equipment on-site and the overall project program requirements. Part of the presentation will further show the applicability of the developed design during construction (deformations, monitoring field observations) and lessons learned for future cavern construction in Australia.CITATION:Lagger, H, Purwodihardjo, A, Barrett, S V L, McKenzie, N and Taylor, E, 2014. Temporary support design for the largest road caverns ever built in Australia – the Lutwyche Caverns, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 399–410 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Iwu GO, Almond DP, Joasoo _

The gravimetric integral Knudsen effusion method was used to measure cadmium activity values in binary liquid In-Cd alloys in the range 523 to 573 K. The activity measurements together with other studies from the literature indicate that special bonding conditions exist in the melts near a composition corresponding to InCd3. Sound velocities in In-Cd melts were also measured using a precision pulse-echo over- lap method in the range 404 to 953 K. The frac- tional deviation of experimental and ideal isentropic compressibilities at 623K shows a functional dependence on composition with a pronounced maximum near the composition 75 at.%.

Jan 1, 1980

By H Law, M Muller

Mount Isa Mines (MIM) Copper Concentrator currently utilises Agitair 120 banks for its roughing flotation circuit. Apart from a rotor change, the only other significant work completed to the Agitair banks since their installation and commissioning over 40 years ago has been a like for like refurbishment in 2016. The Agitair banks at the MIM Copper Concentrator currently utilise the Pipsa rotor design which progressively replaced the original Chile X rotor design in the 1980’s and 90’s in the copper concentrator. Since the development of the Pipsa rotors, modern rotors such as the Dorr-Oliver (DO) high shear rotors have been released to the market with proven recovery and concentrate grade improvements over previous rotor designs. This paper aims to detail the installation, testing and comparison of Pipsa versus Dorr-Oliver rotors in two different flotation sections of the MIM Copper Concentrator.CITATION:Muller, M and Law, H, 2018. High shear rotor trials in the Mount Isa Mines Copper Concentrator, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 393–402 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By J. K. A. McLEOD

Address by the President of the Institute (Mr J K A McLeod) in presenting the Institute Medal to Howard Knox Warner, C.B.E. Address by Howard Knox Warner after accepting the award.

Jan 1, 1978

By F Phillips, E Deucker, J Kato

It is challenging to determine the optimal mining strategy to maximise value when a mine plan includes mineralised material which does not meet the full cost of mining but has value exceeding the variable cost of mining (‘marginal material’). Mining too much marginal material dilutes the operation’s head grade and undermines profitability. Conversely, leaving too much metal behind fails to achieve the full value of the endowment. Finding the balance between the two will maximise value delivered from the asset. This dilemma has traditionally been approached by calculating a suite of cut-off grades to define the grade of material that meets economic targets for an orebody (or zone within) and should therefore be included in the mine plan. A problem with this approach is that individual mining blocks within the zone have different costs, value and confidence levels, with each having economic co-dependencies between them. Blocks of identical grade but different mining contexts will have distinctly different economic outcomes. For example: • a block may be a low-grade increment or shell around a higher-grade stope; • a block may be available to be mined when there is spare mining capacity; or • a block may defer access to significantly higher cash flow material. Each of these circumstances would result in different value from the blocks if included as part of the mine plan. Cut-off grades calculated as averages over zones of material, or in isolation from schedule-based information, are missing the entire mining context that determines the ultimate economic outcome of making a mining decision. There are tools and techniques available to address this for open pit mining, however underground mining has different nuances. There are more intricate economic and physical dependencies between potential ore blocks, and importantly, the decision to leave material in situ can be made at any time. The case study in this paper explores a new methodology for underground mining, targeted towards strategic planning applications. It examines whether the economic logic usually applied via cut-off calculations can be implemented in the schedule so that optimal economic decisions can be made on a block-by-block basis, taking into account the mining context of the block, with the objective to maximise asset value. The results of the case study scenarios in Table 1 demonstrate the magnitude of the potential improvement in NPV that can be attained by a block by block valuation approach

Mar 15, 2021

By C te Kloot, Z Liu

Blast performance and the resulting drawpoint condition and volume of oversize has the potential to impact operator safety and mine productivity. Underground measurements showed that approximately 14 per cent of production rings in the Ernest Henry Mine (EHM) sublevel caving (SLC) operation had either overbreak in the brow or left collars. There were also oversize rocks reporting to approximately 30 per cent of drawpoints, which accounted for over 7 per cent of total production and significantly impacted production rates. A series of trials were conducted in 2015–2016 at EHM to test changes to certain charge parameters in an attempt to optimise blasting results and, in particular, reduce oversize and overbreak. The detailed analysis conducted included field observations, hole surveying, blast monitor analysis and blast modelling. There were a total of nine charge parameters tested in the project, which fell into two major categories: energy distribution and inter-hole delay. These were based on observations made in establishing baseline data and those parameters most likely to have a significant impact on overbreak and oversize.Key results from the project included oversize reduction and improved brow conditions when energy distribution was reduced through changing charge lengths in certain holes in the standard charge plan. Similar benefits were also seen when the inter-hole delay between blastholes was reduced from 50 ms to 25 ms. Based on these results both changes were made to the standard production ring charge plan at EHM.Moving forward, the aim is to continue monitoring the results from the changes made on all levels to ensure efficiencies are being realised and sustained. A 3 per cent improvement in oversize as a percentage of total tonnes and improved brow conditions not only has a positive impact on production rates, but removes people from any potentially hazardous situations and contributes to a safer working environment.CITATION:te Kloot, C and Liu, Z, 2017. The evolution of production blasts at Ernest Henry Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 33–38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Connell JE

The Worthing Mine near Hallett Cove. 20 km southwest of the cite of Adelaide, belongs to Aus- tralia's first mining era, which took place in South Australia between 1841 and 1851 (Figure 1). Oper- ations began in 1849 only six years after the com- mencement of metal mining in Australia at Glen Osmond. Although not as historically significant as Glen Osmond (1841), or the much larger copper mines of Kapunda (1844) or Burra (1845) its importance lies with its Cornish enginehouse and chimney. The Worthing enginehouse, built in 1851-1852 is the oldest remaining in Australia and certainly the most significant relic of Australia's first mining era. Six other stone enginehouses were built during that period: at Kapunda in 1848 and 1850: at Burra in 1849, 1850 and 1851; and at Tungkillo in 1849. All of these houses have long since dis- appeared although the foundations of one (Kapunda, 1850) still remain. The significance of the Worthing site is enhanced by its magnificant environmental setting in the bare, steep valley of Field River. Currently (1986) the Worthing Mine is the only site within the City of Marion which is on the Register of State Heritage Items. The site is also included in the Classified List of the National Trust of South Australia and on the Register of the National Estate.

Jan 1, 1987

By Q Gong, J Li, J Zhao, Y Zheng

Excavation by tunnel boring machines (TBMs) offers many advantages over conventional excavation methods, in terms of safety level, working environment, advance rate and overall cost. While TBMs have been extensively used in civil tunnel construction, they are also viewed as a competitive alternative to the drill-and-blast method for underground mining, attracting increasing attention from the mining industry. This paper presents an overview and general assessment on applications of TBMs in mines, by reviewing more than 60 TBM applications in underground/open pit coal and hard rock mines around the world. The projects range from the early exploratory trials of TBMs in mines in Germany, England, South Africa and America in the 1960s and 1970s, to the ongoing projects in Australia, China and Chile. The paper focuses on the geological compatibilities, the problems encountered, the solutions undertaken and the lessons learned from those projects. The paper summarises the progress made in the past and highlights the challenges faced by TBMs in mining due to complex ground conditions and geometrical requirements. With the technological advances of TBM and experiences gained in the past, more applications of TBMs are expected in underground coal and hard rock mines.CITATION:Zheng, Y, Gong, Q, Li, J and Zhao, J, 2014. A review of the applications of tunnel boring machines in mines, in Proceedings 15th Australasian Tunnelling Conference 2014, pp 691–704 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By G J. Harbort, K Lam, C Sola

The relationship between the geology of porphyry copper deposits and their processing performance is an area of interest. Being able to predict comminution properties of the ore from physical characteristics and geological descriptions would allow an increase in the precision of capital cost estimates, operating cost estimates and throughput rates. This geometallurgical approach would reduce the requirements for expensive comminution tests.As the comminution circuit is the highest capital cost item in the plant and a possible throughput bottleneck, understanding the variability in hardness within the orebody is critical. A geometallurgical model allows calculation of ore hardness values in mining blocks from ore characterisation data. This model subsequently uses a combination of simulation and power-based approaches to relate ore hardness and flotation feed size to grinding circuit throughput.This paper reviews the geometallurgical models developed for seven porphyry copper deposits and discusses the strengths and shortfalls of the methodology and similarities and differences between the different deposits.CITATION:Harbort, G J, Lam, K and Sola, C, 2013. The use of geometallurgy to estimate comminution parameters within porphyry copper deposits, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 217-230 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Y Durkheim, P Saunier, L Ameglio

"In the last decade Afitex developed the Draintube™ geocomposite, which provides simultaneous drainage and waterproofing functions. This new type of drain tubes planar geocomposites (DTPG) differs from other geocomposites as the drainage core is composed of multiple corrugated and perforated pipes instead of biaxial or triaxial nets. It is furthermore associated with needle-punch stitched layers of non-woven geotextiles, which act either as capillary mediums or as filters.In this paper, the structure of the Draintube™ drainage composite is presented along with its key properties and the drainage mechanism associated with its particular structure.The relevance of this kind of structure is then reviewed based on past and current laboratory bench evaluations and field installations for mining applications such as the covering of acid rock drainage (ARD) tailings for the Central Manitoba Mine (Canada) site-rehabilitation; and as a pregnant solution collection layer in heap leach pads.Some of the demonstrated critical advantages of Draintube™ in the mining industry are as follows: reduction of the thickness, hence lower volume of granular drain layers improvement of fluid and gas collection and reduction of the hydraulic load reduction of secondary collector network mechanical protection of the sealing membrane fast and economical installation of interlifts stability under extreme conditions (compression, temperature, pH) increased stability of entire covering system and reinforcement of protection of dykes filtration of the covered material customised drainage positive connection of the geocomposite to collector pipes enable leaks detection (using a conductive textile layer) with an electrical test.CITATION:Saunier, P, Ameglio, L and Durkheim, Y, 2015. Tubular drainage and lining geocomposite for mine tailings and heap leach pads, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 297–304 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 27, 2015

By S Norman

The Water Delivery Alliance (WDA) was established to design, construct and commission the pump station and desalinated water delivery pipeline to link the desalination plant on the Kurnell Peninsula (constructed by others) with the existing distribution network at Erskineville, Sydney, Australia. The WDA consisted of McConnell Dowell Corporation Ltd (Macdow), Bovis Lend Lease Pty Ltd (BLL), Kellogg Brown and Root Pty Ltd (KBR), Worleyparsons Ltd (WOR), Environmental Resources Management Group Inc (ERM) and Sydney Water Corporation (SWC).Sydney’s Desalination Project is one of the initiatives to secure Sydney’s water supply against the effects of climate change, population growth and drought. The desalination plant, 100 per cent powered by renewable energy, can supply up to 250 million litres of water per day (mld), which is up to 15 per cent of Sydney’s water needs. The project involved the construction of an 18 km pipeline with an ultimate capacity of 500 mld to accommodate any future increase in the output of the desalination plant.The Alliance procured three full-face tunnel boring machines (TBM) from Herrenknecht AG to construct the 6.5 km of tunnel that would provide a conduit for the DN1800 welded mild steel cement mortar lined (MSCL) pipeline at a number of locations along the route. Nineteen shafts and 16 tunnels were required to complete this work.Crucially one of the TBM drives involved construction of a tunnel into Botany Bay under protected marine life habitats; enabling the connection of the MSCL water carrier pipeline into the dredged section of pipeline underwater, approximately 800 m off-shore in Botany Bay.This paper details the retrieval of the 17.4 m long TBM from the ocean floor upon completion of the Botany Bay tunnel allowing for subsequent use on the Project. Elements covered in the paper include the 835 m tunnel, design and construction techniques for the tunnel and recovery, and details of the methods used to install the DN1800 water carrier pipeline.

Mar 8, 2011

By C J. Unger, T Baumgartl, C J. Bond, P Sabourenkov, V C. Glenn

Social licence to mine is influenced by society’s perception of the mining sector’s ability to effectively rehabilitate mined land and for governments to appropriately regulate that process for the broader community benefit. In Queensland, Australia, many mine rehabilitation personnel working for active coalmines, as either staff, consultants or contractors, belong to the Central Queensland Mine Rehabilitation Group (CQMRG). The CQMRG was established 23 years ago with the aim of sharing informal knowledge related to practical aspects of rehabilitation in order to leave as positive a legacy as possible from mined land. This voluntary group of professionals also includes members from regulatory agencies and civil society. Within the dynamic regional mining environment, mine rehabilitation professionals benefit from sharing their informal knowledge.CQMRG is currently a group in transition. Mining boom and downturn cycles have exacerbated the loss of accumulated knowledge in the core CQMRG membership due to rapid changes in personnel at mines in the region. Additionally, some of the most experienced CQMRG-affiliated rehabilitation practitioners are approaching the end of their careers and want their valuable and less formal knowledge retained. This paper discusses the development of a research project that emerged in response to the anticipated loss of several decades’ worth of valuable knowledge as rehabilitation practitioners in CQMRG left the region or the workforce.CITATION:Unger, C J, Bond, C J, Baumgartl, T, Glenn, V C and Sabourenkov, P, 2016. ‘MRC-wiki’ – a mine rehabilitation and closure knowledge management tool for Central Queensland coalmine practitioners, in Proceedings Life-of-Mine 2016 Conference , pp 39–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

Thank you for this opportunity to address your conference on The role of coal in the New Zealand energy market".New Zealand's energy market has, in common with much of New Zealand, undergone major change following the market reforms of the Labour Government.As far as the energy sector is concerned this change has been for the better, as it has created for the first time in a very long time a "true economic market" for energy in New Zealand.

Jan 1, 1990

By N Yarahmadi

Characterization of pore pressure is critical for appropriate design of tailings dams. Furthermore, if seepage rates through tailing embankments increase unexpectedly or become uncontrolled, undesirable conditions may prevail to progress piping or internal erosion that could lead to the dam’s instability or ultimate failure. A three-dimensional seepage analysis was performed on a tailings dam using finite element method to find the rate of seepage and pore water conditions in the embankment and foundation. The results were then compared to a conventional two-dimensional seepage analysis carried out on the typical cross section of the embankment and the field data acquired from the instrumentation system. Considering the monitoring data, comparison of seepage analyses results for the two and threedimensional models, showed that the results of the conventional two-dimensional seepage analysis are significantly underestimating reality. Relying on two-dimensional seepage analyses might result in underestimation of seepage rates and impact the safe operation of tailings dams. Similarly, unrealistic prediction of pore water pressure conditions, based on simplified seepage analyses, can lead to overestimation of the rate of strength gain of material and consequently safe embankment raising rates.

Jul 1, 2021