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Currently an Australian Standard for tunnel fire safety is being developed for road and rail tunnels. Other local guidance relating to tunnel fire safety that has recently become available includes publications by both the Roads and Traffic Authority and RailCorp of New South Wales. Internationally, the World Road Congress has completed its 2004 - 2007 cycle, which has resulted in a number of publications. International developments in rail guidance include a new European Standard regarding fire safety in railway tunnels that will come into effect in July 2008. In addition, the National Fire Protection Association committee NFPA 130 are in the process of revising their standard for fixed guideway transit and passenger rail systems, which is due for publication in late 2009. This paper outlines the status of these and other recently published relevant local and international fire safety guidelines and their implications for tunnel projects in Australia.

Jan 1, 2008

By I Lourel

In evaluating the installation of an in-pit crushing and conveying (IPCC) system for any mine, a number of options are available for each of the dig side, transport and dump side operations. Some of them are moreappropriate than others; given the pit arrangement, the material being handled and the rates at which it needs to be moved. This paper seeks to document the options that might be employed, and to rank them in terms of their applicability at any mine and their practicality overall, with a view to nominating those that would be most suitable for further study.

Jan 1, 2009

By J D. Goldsworthy

The McPhee Creek bedded iron deposit is a recent discovery made by Giralia Resources NL (Giralia) in the northern Pilbara of Western Australia. The deposit lies 30 km north of the town of Nullagine along the southeastern margin of the East Pilbara Granite-Greenstone Terrane (EPGGT).The McPhee Creek area is located in the Kelly Greenstone Belt in the southeastern part of the EPGGT. The Archaean aged greenstone belt consists of volcanic and sedimentary sequences including the Warrawoona Group and the Gorge Creek Group. The McPhee Creek iron ore deposit lies within banded iron formation (BIF) rocks of the Gorge Creek Group. The structure of the McPhee Creek area is dominated by a northeast trending, upright synform (Sandy Creek Syncline) and associated folding that is truncated by northeast trending faults in the east. Iron ore mineralisation is predominantly stratabound and follows the dip of the bedding – however, in some areas, particularly in the southwest of the deposit, mapped steep to moderate dips of bedding planes are at odds with underlying fl at mineralised zones in drill sections. Zones within the deposit that contain substantial thickness of iron ore correspond to areas of complex folding suggesting structural control and iron enrichment in fold hinges. Petrographic analyses confirm mineralisation is goethite dominant and the deposit is strongly supergene enriched.Giralia initially identified iron ore potential in the McPhee Creek area through the presence of a small known channel iron deposit (CID) mesa. Giralia began exploration in 2008 by re-drilling a portion of the CID (subsequently named Crescent Moon) and reported a small low-grade Inferred Mineral Resource. Target generation in the wider area utilising Geological Society of Western Australia maps and Ikonos satellite images identifi ed strongly ferruginous outcrops associated with major structures along an 8 km long range located 2.5 km to the west north-west of the Crescent Moon CID deposit. In late July 2008, a total of 62 rock chip samples were collected during a helicopter supported sampling program conducted at McPhee Creek. Samples taken from haematite-goethite enriched BIF and canga zones outcropping intermittently over the 8 km length of the western and central areas of the prominent range assayed up to 63 per cent Fe. These zones represent the discovery outcrops and surface expression of the McPhee Creek main range iron ore deposit.Follow up sampling, geological mapping, bulldozing of access tracks and ramps and reverse circulation (RC) drilling commenced in September 2009. A maiden Inferred Mineral Resource was announced by Giralia to the Australasian Securities Exchange (ASX) on 15 December 2009.The current Indicated and Inferred Mineral Resource at December 2010 stands at 260 Mt grading 56.2 per cent Fe, 0.12 per cent P, 6.7 per cent SiO2, 2.3 per cent Al2O3 and 9.5 per cent LOI at a 50 per cent Fe cut-off. McPhee Creek is one of the largest iron deposits found in Archaean BIF in the northern Pilbara.

Jul 11, 2011

By S Thacker, M Noakes

The Newmont Tanami Operations (NTO), formerly the Granites Gold Mine, commenced operation in the mid-1980s with tailings deposition evolving over the past three decades as production has increased and the operation has expanded. Paddock-style tailings storage facilities (TSFs) and in-pit tailings deposition have fulfilled the tailings requirements for NTO over its lifetime with the technical specifications of these facilities improving over time in line with the positive development of standards, guidelines and best practice.This paper reviews the options for tailings storage facilities at NTO and the many considerations that have been analysed and deliberated upon before settling on specific TSF types and designs. It also explains the operating philosophies of the tailings deposition and how the facilities have always strongly maintained the optimum capture and retrieval of water. The current TSF design and criteria is presented, along with the introduction of dry tails harvesting for use in paste production as a backfill product for the underground mine. Tailings deposition and recovery remains a critical function of the Granites process to ensure long-term operation and gold production.CITATION:Thacker, S and Noakes, M, 2015. Newmont Tanami Operations – tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 305–314 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By J B. Pateiro-Fernßndez, M Fuchsschwanz, G Deissmann, S Ahmad

Quang Ninh province is the most significant coal producing region in the north of Vietnam. The Nui Beo Coal Company (NBCC) operates open pit mines in Quang Ninh province and the waste overburden produced is dumped as sidehill fill in the Chinh Bac waste dump site. In the past, no special consideration has been given to the environmental impacts during the dumping operations. The mine waste is transported in trucks from the mine site to the dumping site and the loading, hauling and dumping operations are the main sources of dust emission. Rain events, especially during the rainy season, cause the generation of contaminated surface water as well as seepage of water through the dump at a number of locations. The existence of cracks at the top of the dump can pose serious stability problems with heavy rain events leading to failure of slopes which can potentially disturb vast areas of land currently used for agricultural purposes and human settlement. For sustainable development at the Chinh Bac waste dump site in the future, apart from the social and economic considerations to be assessed, there is an absolute necessity for environmental protection measures to be in place both during and after the dumping of the mine waste overburden. Research Association Mining and Environment in Vietnam (RAME) is working to develop and implement concepts for the mitigation of environmental problems emerging from dust, contaminated water and lacking slope stability to ensure successful rehabilitation of the coal mine waste dumps in the north of Vietnam. Within the framework of RAME, the Institute of Mining Engineering I (RWTH Aachen University) is managing and working to develop the stabilisation concepts for the solid mine waste dump in collaboration with the Chair of Geotechnical Engineering (RWTH Aachen University), Brenk Systemplanung and the Vietnamese group of companies VINACOMIN (Vietnam National Coal-Mineral Industries Group). The most economical and environmentally sound operations, as well as locally adaptable environmental protection measures, are essential for the sustainable development of the dumping operations at Chinh Bac dump. This paper describes the dump site and the sustainable development possibilities with an emphasis on the environmental protection and stability problems at the Chinh Bac waste dump.

Jan 1, 2009

By J J. Boshoff

This iron ore mine site, located in the Pilbara region of Western Australia, commenced operations in 1998, with ore derived by mining of open-cut pits in Channel Iron Deposits (CIDs). A portion of the ore extracted at the mine is processed at wet processing plants that produce both ore saleable product and waste fines (i.e. tailings) slurry. The waste fines produced at the wet plants are presently stored within Waste Fines Cells (WFCs).Waste fines cells A (WFCA) and B (WFCB) are located within an Autonomous Haul System (AHS) area and consist of embankments that span the width of the pit in east-west alignments. Technical studies and design analyses were carried out to support embankment raises and ongoing development of the WFCs. During operation and development of the WFCs, a multitude of simultaneous activities took place to the immediate north and south of WFCA respectively. These activities included the construction of the embankment raises using the AHS fleet, mining of the CID to not only mine the ore but to also create future deposition space for WFCB, blasting next to the WFC embankments as part of the mining activities, seepage collection and dewatering of the pit in the vicinity of the WFC.This paper discusses the material characteristics, design approach, construction staging and equipment requirements, blasting near embankments, water management, facility consequence category and closure concept.CITATION:Boshoff, J J, 2018. A waste fines cell with a multitude of concurrent activities, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 39–49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By X T. Nguyen

Western AustraliaÆs Mining Act 1978 was amended in 2010 to provide for the requirement of a mine closure plan to be submitted to the Department of Mines and Petroleum (DMP) for approval, as part of a mining proposal application. The mine closure plan must be prepared in accordance with approved guidelines. Guidelines for mine closure plans were developed to assist the mining industry in Western Australia to plan and implement effective closure of mines. The guidelines focus on the application of integrated mine closure principles and industry best practice information on mine closure. This, includes stakeholder consultation, risk based approach, data collection and monitoring, development of completion criteria and financial provision.Due to the potential high level of public interest in the guidelines, extensive consultation with stakeholders was conducted. The purpose of this paper is to share experiences from the consultation process.CITATION:Nguyen, X T, 2012. Mine closure guidelines for Western Australia and consultation process, in Proceedings Life-of-Mine 2012 , pp 43-46 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By L Boczek

The term Engineer of Record (EoR) is commonly used in North America and South Africa to define the responsible person for the design, construction and operational phases of a tailings storage facility (TSF). Recently, this role has been elevated in prominence within Australia, but what does it really mean? Recent updates to international TSF guidelines suggests appointing an EoR is good practice, but where does the responsibilities of the EoR start and finish. Interestingly, both Samarco and Mount Polley failures had active EoR’s in place. This suggests that nominating an EoR alone, is not the full answer to mitigating the potential for a TSF failure. Appropriate construction and operational practices are key to the success of the design of TSFs, where all too often, operators ignore the operating plans developed by the designer. To be successful, a key consideration of the EoR role, is involvement in the operational phase of the TSF. This requires ‘buy-in’ from the mine managers and a change in the way TSFs are perceived by site. This paper explores how the roles and responsibilities of the EoR can assist in improving governance of TSFs if implemented effectively and what role the client has to ensure the success of the EoR.

Jul 1, 2021

By A R. Proudman, A H. Purvis

The Granites Gold Mine Callie gold deposit is located 550 km northwest of Alice Springs in the Tanami Desert. Gold mineralisation occurs due to a complex interplay of geological factors which include but are not limited to favourable lithology, structure, alteration and quartz veining. High-grade mineralisation, while pervasive under favourable conditions, is highly variable over short distances and is very nuggetty. In contrast, the lithology and geological structures that host the mineralisation are very continuous. Orebody modelling techniques have evolved over time because of a growing understanding of the mineralisation controls. Modelling issues such as sampling and assaying accuracy, modelling method, data density, gold population statistics, geological interpretation and domaining, grade boundary and calculation conditions, and model block size are constantly being reassessed in an effort to increase understanding of the mineralisation controls and modelling accuracy. The evolution of the modelling process in response to increasing data levels and a growing understanding of the mineralisation controls has resulted in changes to the perception of the orebody size and style. This has caused the choice of underground mining method to be revised several times and the process to final mining method selection to take longer than usual. In order to achieve the planned production start-up date of July 1998 the process has been allowed to progress in parallel with development of the underground mine. This paper describes the resource modelling and mining method selection process applied to the Callie underground mine and some of the issues which have contributed to its evolution. Some conclusions that are relevant to the efficient planning and development of new mining projects in general are presented.

Jan 1, 1998

By Secis R

Northparkes Mines is located 27 km northwest of Parkes in central west New South Wales. The E26 deposit is the largest of all defined to-date in the area, containing over 50 per cent of Northparkes' resources and reserves. The combination of orebody geometry and geotechnical characteristics provide ideal conditions for the block cave method of mining of the first lift of the E26 deposit. Although this method of underground mining has been used for decades in other countries, E26 is the first example of its use in Australia. Copper-gold mineralisation at Northparkes is related to quartz monzonite porphyries that have intruded coeval Ordovician volcanics. Sulphide mineralisation (dominantly bornite and chalcopyrite) occurs principally within quartz veins associated with the porphyry intrusions. Veining and mineralisation occurs within both the porphyries and volcanics. To optimise the recovery of a resource within a block cave mine, a good understanding of the rock mass and ore flow characteristics is essential. These have a significant effect on the fragmentation size and range and on parameters such as the drawzone spacing, height of interaction zone and dilution entry. As ore within a cave column moves and mixes when material is extracted from below and beside it, the total reserve extracted is unique for a particular draw strategy/production history. Until recently, reserve estimates and production schedules were based on the application of a uniform dilution factor to the tabulated resource. However, given the complicated flow and mixing within the cave column, such a simplistic approach can produce erroneous results. Northparkes Mines purchased and sponsored the upgrading of a commercially available software package specifically developed for modelling removal of resource blocks under caving conditions. This Gemcom software package, PC-BC, has been used for mine planning, reserve reporting and production scheduling. Blocks within it resource block model are converted into a mineable reserve taking into account mixing and dilution during depletion of drawcolumns (by horizontal and vertical redistribution of insitu tonnage and metal). As PC-BC gives individual drawpoint reserves, it can be used during the planning stage to determine whether or not a drawpoint is economic. For E26 Lift I an optimal layout containing 130 drawpoints has been developed based on a nominal 14 m x 14 m drawpoint spacing and a 0.8 per cent equivalent copper (eCu) cut-off grade. Annual production schedules for the depletion of material above this layout are based on: I higher tonnage removal from higher grade drawpoints in the early years of production; and 2 drawpoint production rates proportional to the total tonnage of orr remaining in the drawcolumn up to the optimal height of draw tier subsequent years. The reserve is tabulated from the combined annual production schedules over the life of the lift. The pre-mining reserve for Lift I of E26 is 26.6 Mt at 1.43 per cent copper and 0.39 g/t gold, of which approximately 23.4 Mt will be extracted under caving conditions. By scaling down the annual production schedule, weekly drawpoint tonnage calls can be given for short-tern production scheduling.

Jan 1, 1997

Goldfields (Tasmania) Limited operates a small, high-grade underground gold mine on the West Coast of Tasmania, 30 kilometres north of Queenstown. The main orebody, Zone 96, was discovered in 1989, with major development work commencing in 1993. The mine was officially opened in July, 1996. Initial production came from a shallow orebody known as the Sill Zone, some 50 - 150 m below surface, which was accessed by a 1 in 8 decline. Zone 96 lies between 350 m and 550 m below the surface and is accessed by a 402 m deep, 3.2 m diameter internal shaft from the collar level located 100 m below surface. The main ore extraction system in Zone 96 is mechanised cut and fill, using high density paste fill. Run of mine ore and waste are hoisted in a single 5.5 tonne overturning skip, then trucked from the underground collar to the gold plant ROM pad or waste dump, respectively. Ground conditions in the mine vary with orientation and proximity to major faults. The gold is contained in a sequence of strongly altered volcanic rocks adjacent to the Henty Fault. Most of the gold is contained in massive quartz, ranging in width from 0.5 m to 7 m, which has been subjected to substantial faulting. Average mineable grade is about 27 grams gold per tonne. Ore reserves in 1996 proved an initial mine life of approximately 4.5 years at 90 000 ounces gold per annum, with significant potential for additional resources from extensions to Zone 96 and adjacent zones. The lease is located in an environmentally sensitive area and a very high standard of environmental management is an essential part of the operation. This paper describes the relevant aspects of mining at Henty including grade control, ground support, backfill placement and environmental management.

Jan 1, 1998

By Baker G

The detailed mineral composition of the lead-zinc ores at Captain's Flat was first studied in 1942 (Edwards, 1943).At that time the workings did not extend far below the 750ft. level. Since then development has been extended to the 1,390ft. level, and -at the request of the management of Lake George Mines Ltd., an examination of the ore from the deeper levels has been made as part of the research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organization.This account is. based on that examination (Mineragraphic Rept. No. ,537, C.S.I.R.O.)GENERAL GEOLOGYThe geology of the Lake George Mines has been described briefly in The Geology of Australian Ore Deposits (1953), and in much greater detail in an unpublished report by K. Glasson (1952). The area consists of fossiliferous Upper Ordovician sediments overlain by volcanics (Kohinoor VoJcanics), and by fossiliferous Silurian sediments. The volcanies comprise a series of· flows ranging in' composition from dacite to rhyolite, with interbedded tuft's and shale lenses.The region has been strongly folded. The regional strike is from 340° to 355°, and dips are from 75°W. to 75°E, A major syncline, pitching 200 N., occupies the centre of the area. The Kohinoor Volcanic'l outcrop as two bands which represent the east and west limbs of this syncline.The Volcanks in the western limb, with whIch the orebodies are associated, are more strongly sheared than those in the eastern limb.

Jan 1, 1953

By R Kjar

Globally, it is anticipated that the mineral sands industry will enter a period of short supply. Demand for both titanium dioxide and zircon is forecast to continue increasing, with new projects needed to come on-stream to fill the supply gap. Victoria is well placed under this scenario as a source due to the high quality of its mineral assemblage, its excellent resource grade and the globally significant size of its mineral sands resources.Australia’s mineral sands rich Murray Basin remains under-developed, especially at its extensive Victorian margins. Development to date has not progressed adequately for the reasons of technology difficulty, history of competition with other jurisdictions and the absence of a platform that requires development as a consideration for security of tenure. Victoria’s mineral sands potential is not just about the Murray Basin, in addition, there have been discoveries in the Gippsland Basin and prospective sites in the Gippsland Basin remain under-explored. Key problems included the lack of available ground for potential developers and the intellectual property of solutions to technological problems associated with the fine grained mineral deposits belonging to a previous developer (with patents now expired).As such, the timing is right to re-visit the potential of the Murray Basin as a site for long-term development with high returns based on current and predicted prices.In order to understand why Victoria’s earth resources in general, and mineral sands in particular, remain under-explored and undeveloped, the Department of Primary Industries initiated an internal review of its role in encouraging and supporting investment in the earth resources sector.As a result, the Victorian Government has committed to taking action to encourage effective ground turnover and acknowledges that a new focus on engagement with industry is needed to bring new investment to the State. The revision of the Mineral Resources (Sustainable Development) Act 1990 provides an opportunity for the government to better align its legislative processes with industry project lifecycles and facilitate access to valuable resources that currently remain undeveloped.Victoria has a track record in assisting projects reach development stage. Iluka currently has two operations in the State in addition to its mineral separation plant that is capable of processing HMC from its South Australian operations. Iluka is expected to ramp up its Murray Basin Stage 2 operations with the WRP mine scheduled to come on line in early 2012. Meanwhile, Astron is actively seeking partners for its Donald Mineral Sands project. The project is becoming increasingly attractive given the recent price hike in zircon; Astron has access to an estimated five to 6 Mt of zircon in its Donald WIM 250 deposit.Given its substantial and valuable mineral sands endowments, the State of Victoria should sensibly be the centre of future investment in project development. However, as previously mentioned this is currently not the case. The Government is therefore committed to implementing new measures that protect security of tenure but ensure that genuine companies can access endowments where they have a clear intent to work those resources.

Oct 5, 2011

By L H. G McClean

Environmental, social and governance (ESG) factors have always been important to the minerals industry and is now considered one of our most important opportunities (and risks). Getting it right from the beginning is critical for the minerals industry, and that starts with mineral exploration. Exploration, or the process of investigation of an economic mineral deposit, is generally low impact and short-term. Exploration operations vary in size and scale and often shift priority, focus and location relatively quickly. Australia is a highly regulated jurisdiction with different regulatory systems and requirements in every state and territory. Most mineral exploration is undertaken by junior exploration companies or ‘explorers’. Exploration companies are lean operations with limited staffing and resources, traditionally with no income apart from funds raised or work through partnerships. Funds are tight and administrative investment is minimised so that investment into activity on the ground is maximised. All these variables mean that understanding and implementation of ESG frameworks for an exploration company can be challenging. ESG is a fast-moving sector with currently multiple frameworks and reporting standards. Interest from community and government stakeholders as well as investors and off-take partners has been growing, with mandatory reporting soon to be implemented. The upcoming changes to the JORC Code will ensure that ESG considerations will be a key component of all public reporting. Resources have been developed to support explorers implement, manage and report on ESG considerations. Due to their scale, agility and direct importance of land access and social licence, many explorers are not the ‘cowboys’ (or ‘cowpersons’) of the industry, but industry leaders in ESG. Strong interest and leadership have led to innovative practices and strongly embedded vertical frameworks that directly contribute to social licence to operate.

Sep 1, 2024

By A Parbhakar-Fox, S C. Dominy

The prediction of acid and metalliferous drainage (AMD) from mine waste materials is critically important during all stages of the mine value chain. However, to determine such geoenvironmental characteristics static and kinetic testing of individual waste units must be performed on representative samples. The importance of sample selection cannot be underestimated; it is the single most critical aspect of any geoenvironmental investigation. Poor sampling techniques and inadequate sample selection will contribute to excessive variance, difficulties in interpretation and incorrect assessment. By undertaking mesotextural characterisation based on hyperspectral mineralogical data (with sulfur assay data if available), opportunities to improve sampling strategies are presented. Such data will inform the selection of samples for low-cost total sulfur, paste pH and geoenvironmental logging, which collectively will allow for accurate AMD forecasting and improved sampling practices to be achieved. Once sampled, robust quality assurance/quality control (QA/QC) protocols must be developed where the use of international certified reference standards become obligatory. This is currently not practised, resulting in inter-laboratory discrepancies when undertaking waste classification. Further improvements in geoenvironmental characterisation testing lies in the adoption of blended static testing protocols, whereby blends of waste materials can be efficiently tested so as to give an early forecast as to whether they will produce acidic or metal-laden drainage. Such information is integral in developing a waste schedule that will allow for a non-acid forming waste landform to be constructed right from the start of the operational phase. Ultimately, improvements in this discipline lie in technological innovations with regards to mineralogical characterisation, and by offering geoscience and minerals engineering students a competent education in the discipline. Collectively, this will empower a step-change in AMD prediction and waste handling, and will make the realisation of the United Nations Sustainable Development Goals a reality, rather than a dream.CITATION:Parbhakar-Fox, A and Dominy, S C, 2017. Sampling and blending in geoenvironmental campaigns – current practice and future opportunities, in Proceedings Eighth World Conference on Sampling and Blending , pp 45–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By G J. Harbort, Z Pokra

It has been observed in several Jameson cell installations where the source for flotation feed is deslime screens, that the recovery of coal particles greater than 0.5 m is not as great as that of finer material. Consequently, a research project was undertaken at a CHPP in the Bowen Basin, Queensland, to assess the possibility of increasing the recovery of coarser particles (+0.5 mm) within the downcomer of the Jameson Cell. The effect of decreasing turbulence and agitation in a commercial-scale downcomer was investigated to assess the effect on the recovery of both coarse and fine coal particles. This paper details the findings of the testwork, summarising the results relating to differences in the operating parameters within the downcomer.

Jan 1, 2005

By R Jacobs, J Yeates

"The Stockman base metals project is situated in State Forest in the alpine area of East Gippsland, Victoria, adjacent to a National Park and within the headwaters of a major Ramsar-listed wetland catchment and the Murray-Darling River system. Site topography is steep, and elevated (650 m – 1200 m above sea level), and subject to circa 1 m annual rainfall, with occasional winter snowfall. The project consists of two volcanogenic massive sulfide (VMS) deposits to be mined by underground methods and treated in a 1.0 Mt/a central concentrator to produce copper and zinc concentrates for export over a ten year operational life. New resource projects are rare in Victoria. Recognising the sensitive setting, planning for the Stockman Project, which is now in the advanced permitting stage, has focused on balancing economic, environmental and social outcomes to ensure social licence to operate is secured and can be maintained. This has involved close attention to triple bottom line (TBL) risks and outcomes. Stockman has successfully gained State and Federal approvals via the Environmental Effects Statement process. The process of obtaining these approvals has required close attention to effective stakeholder involvement, and management of a lengthy and difficult approvals process, which is still to be finally concluded. This paper is a case study of the process of that permitting and the issues encountered to date. Key learnings from the experience have included: successful approvals require close attention to much more than just the project and its technical aspects and physical setting – effective stakeholder involvement and endorsement is critical the differing consultation requirements for local, regional and government stakeholders, to design and plan implementation of a project to meet TBL objectives, and to gain social licence to operate within the Victorian approvals process, the need for an effective lead government agency with policy authority dealing with material policy change requiring post-closure financial sureties estimating realistic permitting time and cost during the project evaluation phase. CITATION: Jacobs, R and Yeates, J, 2016. Stockman base metals project – sustainability, social licence to operate and permitting lessons learnt, in Proceedings Project Evaluation 2016, pp 98–110 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By D Reid, J Vinod, M Rahman, A Fourie, T Vo, J Ayala, A Russell

This paper reports on an industry and Australian Research Council funded research project, TAILLIQ, that is a joint initiative between four Australian Universities. The paper discusses the accuracy with which the critical void ratio can be determined for a given tailings; it does this by presenting the results from a ‘round robin’ study in which 18 geotechnical laboratories around the world participated, testing the same tailings (sampled from a gold mine in Western Australia). The results were variable, although a reasonable number were very similar, as described in the paper. The paper provides additional test data for sandy silt gold tailings recovered from a sponsor’s site in Australia, including preliminary calibration chamber test data, results from direct simple shear tests and characterisation tests to determine unsaturated geotechnical properties.

Jul 1, 2021

By P Trout, B Macaulay

Ridgeway Gold Mine (RGM) is an underground sublevel caving (SLC) operation that is owned and managed by Newcrest Mining Limited (NML). Production drill and blast practices are critical to the success of the SLC method at RGM. SLC production ring precharging was introduced in November 2001 to enhance these practices and deliver safety, productivity and cost improvements. Current precharging practices require up to two rings to be loaded ahead of the ring to be blasted in each drawpoint. The explosive may be required to remain in the up-holes for periods of four weeks or more prior to blasting. During this æsleepÆ time it is subjected to repeated shock from the blasting ofadjacent rings and from rings in adjacent drawpoints. The project described in this paper was designed to gain an understanding of the factors affecting explosive performance in the precharging environment and to develop explosive products and operating practices that would meet RGMÆs requirements in terms ofsaf ety, reliability and blast outcomes. Several months oflaboratory and field testing were required to characterise the explosive and quantify the effect of post-loading blasting shock. These results were used to determine the most appropriate loading and sleep time criteria for RGMÆs precharging practices. In addition, the information is being used to guide the development of the next generation of emulsion explosives for use in underground precharging operations.

Jan 1, 2005

By B E. De Gee, N Viviers, A Naidoo

In 2013 the Mopani Copper Mine Mufulira plant in Zambia embarked on a project that was aimed at improving concentrator recoveries. The project commenced with the automation of the milling and flotation circuits. This involved the installation of new instrumentation, namely measurement devices and actuators, and the connection of these to new programmable logic controllers (PLCs).The infrastructure changes were followed by the implementation of basic proportional-integral-derivative (PID) controllers on the PLCs. Supervisory control and data acquisition (SCADA) interfaces were also implemented to allow for switching between controller modes, inputting of setpoint variables and to provide a visual display for process monitoring. The final phase of the project involved the installation and commissioning of advanced process control (APC) solutions on the milling and flotation circuits. This work was carried out by Mintek over 21 on-site days. The APC solutions included the MillStar and FloatStar suites of advanced controllers.The MillStar control suite focused on stabilising the mill feed and mill discharge on the two primary mills as well as the flotation circuit feed. Mintek’s CyLas instruments, which provide a measurement of the hydrocyclone underflow angle, were also installed. The measurements were incorporated into the discharge stabilisation control on both milling circuits. The FloatStar level stabiliser controller provided flotation cell pulp level control on fourteen cells, including two columns.Performance tests showed that the Mintek APC system stabilised the mill feed and mill discharge while ensuring the process remained within operational constraints. The MillStar control system utilised the CyLas instrument to prevent roping on the hydrocyclone underflow. This was not always achieved under normal operation. Additionally, the flotation section was stabilised as a result of improved level control by the FloatStar control system.Performance comparisons showed that the Mintek control system improved the operation of the milling and flotation circuits resulting in a greater copper recovery.CITATION:Naidoo, A, De Gee, B E and Viviers, N, 2014. Implementation of an advanced milling and flotation control system at Mopani Mufulira copper mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 363–368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014