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Tailings management trade-off studies are done for all mining projects. There is wide variability in these studies as their approach, details and outcomes are determined by the experience and focus of the project team. While some of these approaches may consider the whole life cycle of the project others may focus only on capital and operating costs and direct environmental impacts. A complete life cycle approach is not standard practice. This paper describes an approach to implementation of formalised life cycle assessment (LCA) following ISO 14044 to tailings management trade-off studies. The paper describes the implementation of the methodological framework for the LCA, ie goal and scope definition, life cycle inventory analysis, life cycle impact assessment and life cycle interpretation. This standardised approach to implementing tailings management trade-off studies following the LCA approach will contribute to the state-of-the-practice in sustainable mine development.

Jan 1, 2009

By A L. de Ambrosis, S J. Clarke, R Bertuzzi, J Redelinghuys

The M2 Upgrade Project involved widening 15 km of the existing M2 Motorway, which is a key route in Sydney’s road network. The Norfolk Twin Tunnels in North Epping convey traffic over a 460 m length of the motorway. The project involved widening the twin tunnels to provide a third lane and breakdown lane in each direction.The widening of the tunnels was fundamentally different to other ‘greenfield’ tunnel projects in that the operation of the tunnel was maintained throughout construction, with motorway traffic permitted close to the excavation faces on a daily basis. The widened works had to integrate with the existing tunnel support, construction details, and mechanical and electrical infrastructure.The existing tunnel afforded the opportunity to review existing ground conditions in the tunnel. Exposures were mapped within the tunnel, and key design parameters were back-analysed from the original monitoring data to provide increased confidence in the assessed impact from the widening works.Traffic capacity of the tunnels was maintained by detailed staging of the works, and included the ability to reopen the tunnels at short notice.A permit to tunnel system was developed to manage the risks associated with re-opening the tunnel to traffic. A comprehensive suite of instrumentation was maintained to provide reliable monitoring data to support this process. Emphasis on the robustness and reliability of tunnel instrumentation provided increased confidence in the adequacy of the tunnel support being installed. The monitoring was routinely compared with design predictions to check the adequacy of the support measures being installed and confirm the design.The approaches and methodologies developed for the widening of the Norfolk Tunnels were effective in maintaining the safe operation of the tunnels throughout the two years of construction, and provide a framework for increasing the capacity of existing tunnel infrastructure in the future.CITATION:Clarke, S J, de Ambrosis, A L, Bertuzzi, R and Redelinghuys, J, 2014. Design and construction for the widening of the M2 Norfolk Twin Tunnels, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 591–602 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Implementation of Fine-Screening in Preparation of KGHM PM SA Sandstone-Carbonate Copper Ore for Flotation

Sep 13, 2010

Operational effectiveness is fundamental to any operation, becoming highly topical in those experiencing less than optimal output from their fleets. It is all encompassing aiming to identify those factors that could be improved within production and suggesting solutions in order to optimise the existing fleet and obtain the greatest capital return on expenditure.Argyle Diamond Mine (ADM) is a large open cut diamond mine located in the East Kimberley region of Western Australia, approximately 180 km south of Kununurra. It is owned and operated by Rio Tinto on a two week on/two week off roster fly-in/fly-out from Perth or drive in/drive out from Kununurra. Through benchmarking the operation between January and June 2002, a study was undertaken allowing identification of areas falling below target. Following this, analysis of annualised hours and production downtimes were undertaken to quantify the potential gains of improvements in these areas. Strategies were then identified as stated in the 2002 mine plan, in operational effectiveness meetings, and by staff members. This project aimed to maximise direct working hours through determination of the main issues hindering performance. External and internal factors were considered and a continuous improvement program (CIP) was developed. The CIP aimed at internal site-based improvement teams to identify and implement solutions for improvement on a day-to-day basis.

Jan 1, 2003

This paper reviews rehabilitation, closure, and post-closure management of the Tui, Golden Cross, and Martha Mines, all of which are located in the Waikato Region of New Zealand. There was no requirement for rehabilitation of the Tui mine, which was abandoned in 1973. There was a requirement to rehabilitate the Golden Cross mine. Mining at that site ceased in 1997, and rehabilitation is now well advanced. When first approved, there were some requirements for rehabilitation of the Martha Mine, but when reconsented in 1998, those were extended, and in addition a requirement for post-closure management was included. As a result, a Trust, funded by the mining company, has been established to take long-term responsibility for the site following completion of closure. The different rehabilitation/closure requirements at each of these sites illustrates that we have learnt something from the experiences of the past.

Jan 1, 2003

By I Canbulat, J Emery, L Yao and C Zhang

This paper documents a process of data analytics and machine learning applied to coalmine roof convergence data. It follows a publication documenting the formation of the database. For each set of analyses Python scripts were utilised to extract data from an SQL database, with subsequent analyses also executed in Python, utilising open-source tools such as scikit-learn. Preliminary analyses with classic machine learning algorithms included multiple logistic regression, K-nearest neighbours, decision tree, random forest, support vector machine, kernel support vector machine, artificial neural network (ANN), naïve Bayes and multiple linear regression. Results indicated that relationships were complex and non-linear, with the artificial neural network most suitable. An ANN model was then refined through a standard process of hyperparameter optimisation and data augmentation to arrive at a final model. Due to the black box nature of the ANN further insight into how the parameters interacted was sought and found with Shapley additive explanations (SHAP values). SHAP values utilise Game Theory, where each input parameter or feature is a ‘player’ while the data set is the ‘team’. The SHAP value is the impact of each player on the target value, essentially establishing the contribution of each input parameter. The results from all analyses are delivered in the paper, together with insights, applications, strengths, and limitations of the methodology.

Nov 29, 2022

By S Jokanovic

At New Zealand Steel MiningÆs Waikato North Head operation a Bucket Wheel Excavator û shiftable conveyor mining system is used to excavate titanomagnetite bearing sand and clay. The system utilises two Bucket Wheel Excavators and two Beltwagons with a two shiftable bench conveyors and two common trunk conveyors to deliver material to a processing plant. The original system was commissioned in 1984 as a high capacity, low cost method of excavating. In 1996 a second Beltwagon was purchased, increasing the flexibility of the mining system.

Jan 1, 2002

By S C. Labram, A Stabile

"Modern train load out stations are becoming faster and have the ability to load a 100 wagon train in less than three hours. At 70 metric tonnes per wagon, that is an average fill rate of 2333 t/h and considering the train is continuously moving, the instantaneous feed rate into the wagon is in the region of 4200 t/h.The main feed conveyor that maintains the level in the surge hopper, above the final weigh hopper, operates in excess of 5000 t/h to ensure uninterrupted charging of the weigh hopper to not disrupt the train loading operation.To avoid demurrage costs (a charge by the Rail Operating Company for exceeding the contractually agreed loading time) the train has to be handled speedily and efficiently and spend the absolute minimum time at the loading facility. Everything else has a much lower priority, including sampling.Thermo Fisher Scientific’s brief was an engineering, procurement and construction management (EPCM) contract to provide a sampling scheme adjacent to the prepurchased and predesigned load-out facility, but which interfaced seamlessly with the loading system of the trains and provided the following: an instantaneous particle size distribution (PSD) result for each truck loaded, and a final PSD for the total train prior to the train leaving the loading facility a crushed (-3 mm) composite sample for chemical analysis for the whole train a composite physical analysis sample for the whole train.The design presented some interesting challenges to our team, but the end result is a system that not only ‘stands alone’ but interfaces seamlessly with the loading system. This paper discusses the design itself and potential improvements to future systems.CITATION:Labram, S C and Stabile, A, 2017. An automatic sampling methodology to determine contractual particle size distribution in rapid train load out stations, in Proceedings Eighth World Conference on Sampling and Blending, pp 229–234 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 9, 2017

In spite of the many contributions that have been made to our knowledge of the creep properties of polycrystalline lead, the precise influence of various factors on these properties is not yet fully understood. Indeed, the position is such that several important points in connection with the creep of lead are a matter of controversy. This has been brought about largely by the fact that, in the case of lead, the changes that are produced in the creep behaviour by slight variations of such factors as the purity, grain sizeand previous treatment are out of all proportion to the magnitude of these variations.In order to study the fundamental properties of lead as related to creep, and so gain a more enlightened perspective with which to consider the creep of lead in general, the work that is described in a series of papers, of which the present paper is the third part, has been carried out. It deals with lead in the form of single crystals.It has been shown (1) - (3) that the grain boundaries as well as the actual grains play a part in the creep of polycrystalline lead. The present work, by eliminating grain boundaries, enables the. contribution of the grains themselves to the process of creep, in other words, crystalline creep, to be studied effectively.This object was, possibly, the major one in this work.

Jan 1, 1940

The Taupo Volcanic Zone inNew Zealand and the Philippine Mobile Belt in the Philippines are characterized by active subduction, active volcanism and high seismicity. The main factors affecting characteristics of geothermal systems in both countries are: tectonic setting, source magmas, maturity of the systems, and depth to the degassing magma body. Within New Zealand, geothermal systems are grouped into arc- and rift-type. Fluids in arc-type systems contain high amounts of volatiles (<20%), with high CO2/Cl, CO2/He, and N2/Ar ratios. Mantle-type volatiles predominate in rift-type systems. Philippine geothermal systems are largely arc-type, the topography is rugged, leading to the separation of water and vapour upflows, as opposed to the overlap found in New Zealand. The relatively shallow depths of degassing magma bodies in the Philippines results in steeper geochemical gradients, leading to higher proportions of arc-type magmatic water (>40%) and higher Cl contents (3000 - 10 000 mg/kg), Maximum temperatures are also higher, reaching up to >400¦C. Arc-type alteration assemblages in New Zealand and the Philippines are similar. Because Philippine geothermal systems are less mature, have higher temperatures and steeper geochemical gradients than New Zealand ones, advanced argillization is more widespread occurring down to depths of 2000 m. Mineral phases are more varied due to the active input of magmatic waters and the formation of vapor conditions at depth, forming P04-, B-, Li-, Ce-, F-, and Cl-bearing minerals at high temperatures. In the Philippines, high temperature magmatic-hydrothermal to contact metamorphic assemblages containing biotite, amphiboles and pyroxenes are relatively common, but rare in New Zealand.

Jan 1, 1995

In the late 1970's and early 1980's a considerable number of large scale open pit mines were developed in N.S.W. and Queensland. At the time these mines were planned, the industry was characterised by rising coal prices, rising fuel prices, and a host of other labour and government constraints different to the situation today. Yet some mines have clearly been able to cope with this change much better than others. While one mine may now be expanding and profitable, its neighbour may still be labouring under painful adjustment processes. This paper examines the major reasons for this difference. It suggests more robust criteria for assessment of future projects to reduce their sensitivity to changes outside management control.

Jan 1, 1990

By G F. Brent, S Hawke, M Rothery, P Dare-Bryan

Mine-to-mill studies have previously demonstrated downstream productivity benefits from relatively modest increases in blast energy, or powder factor. These increases have up to now been limited by safety and environmental constraints, since excessive blast energy can result in flyrock, unacceptable vibration, airblast and wall damage.Here, a new blasting method that overcomes these constraints is presented. For the first time it is possible to employ powder factors that are several fold higher than conventional blasting. Independent modelling has shown that such powder factors can potentially increase mill throughput by 20 to 40 per cent. The economic implications are substantial, both in terms of increasing production in existing operations and in consideration of capital and plant requirements for greenfield sites. In addition, mill electricity and grinding media consumption and their associated costs and energy and emissions penalties can be reduced.This method represents a step-change in blasting practices. It involves a novel design utilising dual blast layers within a single blast event, all initiated with state-of-the art electronic blasting systems. The energies in the lower layer can be as high as five times the standard energies, providing for intense fragmentation of the ore. Results from blast models have been confirmed in field trials of the method.Open cut gold mining, in particular, stands to benefit from this method. As gold grades decline, milling costs and throughput increasingly become constraints on production that can be alleviated with this new method. Additionally, it opens possibilities for improved recovery. Blast modelling studies show that dilution of gold ore within the blast can be managed with the new method. Furthermore, it has been shown that vibration from the new method is actually lower than from conventional blasting, allowing the use of the technique in proximity to mine highwalls and other key infrastructure such as underground orepasses.It is concluded that this new method could substantially increase gold mine production and profitability while reducing overall energy consumption and associated emissions.CITATION:Brent, G F, Dare-Bryan, P, Hawke, S and Rothery, M, 2013. Ultra-high-intensity blasting - a new paradigm in mining, in Proceedings World Gold 2013 , pp 395-400 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By M Kozikowski

The primary purpose of these investigations is to determine dewatering requirements and likely impacts associated with mining operations. Standard aquifer testing techniques were carried out at multiple locations within the Ord Range near Pardoo, Western Australia. Aquifer properties of an oxidised haematite orebody were calculated from test pumping data conducted in five fully penetrating test bores. Hydraulic properties of the Ridley magnetite orebody were calculated based on short term constant rate pumping tests, and packer tests. Packer tests were conducted in undeveloped and uncased exploration holes and diamond core holes. The new data sheds light on the hydrogeological properties of this previously unexplored region of Western Australia.Aquifer testing procedures for each bore included a preliminary step test followed by a constant rate test. Recovery data were collected in each bore over a period of four to six hours. Prior to testing, background water levels and water samples were collected in a network of monitoring and exploration bores to establish baseline water levels, gradients and water quality. Water quality within the bedrock of the Ord Range varies from 2000 to 5500 mg/L TDS whereas water quality within the alluvial sequence of the De Grey River is highly variable (400 to 2500 mg/L TDS), but is predominantly brackish with some water of potable quality which is used to supply Port Hedland. Test pumping supports the conceptual hydrogeological model that consists of a pod like orebody (aquifer) surrounded by low permeability waste rock (BIF), with very weak hydraulic connection to the adjacent alluvial systems. Calculated hydraulic conductivity from test pumping data across Pardoo ranged from 0.01 to 59 m/d, depending on deposit tested.A groundwater model was used to simulate dewatering required in proposed pits and to estimate the impact of dewatering on the surrounding shallow alluvial aquifers. Test pumping and numerical groundwater flow modelling indicate the proposed below water table pits can be successfully dewatered utilising in pit dewatering production bores. Yields from individual dewatering bores will reduce with time due to the reduction in saturated aquifer thickness.Based on the numerical groundwater modelling and field investigations the likely impacts to the adjacent De Grey River alluvial aquifer system (within the Priority 1 De Grey River Water Reserve) resulting from mining and dewatering activities is considered minimal. Recalibration of the groundwater model will be undertaken once several months of dewatering data are available.The aim of this paper is to present a range of aquifer parameters derived through standard aquifer testing techniques for an area previously unexplored in terms of hydrogeological characteristics. It is the goal of the authors to provide this comparison data set for future work in similar geologic media.

Jan 1, 2009

By P K. Smith, N G. Corner, R J. Ryan, D C. Arne, F P. Bierlein

The Reefton Goldfield has produced 67 t of gold from mesothermal vein gold deposits in metasedimentary rocks of the Greenland Group (Cambrian-Ordovician). The Globe-Progress deposit contributed 13.2 t (418,000 oz) of this total, predominantly from quartz veins. Recently a resource of 14 Mt at 1.96 g/t Au (27.5 t or 882,300 oz of contained gold) has been delineated at Globe-Progress in quartz vein remnants and disseminated within adjacent sedimentary rock, much of which has been locally brecciated. The breccias consist of quartz vein and sedimentary wall rock fragments set in a matrix of clay ærock flourÆ and sulphide (arsenopyrite plus minor pyrite and stibnite). Gold, closely associated with sulphide, is disseminated within the breccia. Disseminated gold also occurs in massive siltstone and sandstone adjacent to the quartz veins and breccias. Exploration drilling at Globe-Pogress, and several other Reefton prospects (e.g. Capleston, Merrijigs, Big River and Alexander River), has intersected zones of disseminated arsenopyrite carrying up to 20 g/t more gold. These mineralised sediments commonly have little or no megascopic quartz and or carbonate veining. There is little visible indication of former primary or secondary permeability for the passage of hydrothermal fluid and deposition of gold. However, porosity and permeability were formerly present in inter-granular pore spaces and microveinlets now filled with quartz, carbonate and K-mica. The Fosterville gold deposit in Victoria bears many similarities to the Globe-Progress deposit at Reefton, in terms of age, host rocks, hydrothermal alteration and mineralisation style. Many ofthe disseminated deposits in Nova Scotia, including deposits at North Brookfield and Moose River (Touquoy Zone), have similar characteristics to the Reefton disseminated mineralisation, but commonly have abundant pyrrhotite and some deposits have disseminated metal alloy grains of complex metallurgy.

Jan 1, 2000

During the lifetime of an open pit mining project, each stage from exploration activities to exploitation and mine closure produces disturbances on the mining region. Mined land reclamation plans establish constructive solutions to rehabilitate the disturbed areas. Open pit mining as an effective method for exploitation of a wide range of orebodies especially for massive reserves of shallow metallic substances has exhaustive and harmful environmental effects on the mining project region. Nowadays, closure and reclamation stage in a mining project is emphatically enforced by the relevant environmental protection regulations in many countries. It is therefore obvious that closure and reclamation costs of an open pit mining project, as costs of other stages of project, must be estimated to enter the planning and design processes in open pit mining. Post-mining land use is the most important factor to recognise closure and reclamation costs. Thus, using a model to define optimal land use in planning phase of an open pit mining project is necessary in this regard. In this project a model was developed to define optimal land use regarding different sections of open pit mines such as pit(s), waste dump(s), tailing pond(s), roads, areas for onsite facilities and free land zones which are not mined. TOPSIS and PROMETHE techniques were applied to create the developed model. Lumber production was recognised as the optimal post-mining land use for the pit area of the case study in this project.

Dec 6, 2010

By Hindmarsh J. W, McCoy A. E R

Instantaneous outbursts of coal and gas have occurred at various times in several working districts of Metropolitan Colliery, N.S.W.They have occurred in headings only, under both hand and mechanised conditions, and with seam gas ranging from mainly methane to nearly pure carbon dioxide. A modification of inducer shotfiring using a shear cut was introduced in 1955, and in 1961 full face firing both to a machine cut shear and off the solid was introduced. The current series of outbursts -1961 to 1963 - has been induced under these systems with full control of the time of outburst, but without prediction, and with some disappointing production features.Various aspects of current conditions and practices at Metropolitan are considered singular, such as the coarse granulometry of outburst coal, the prevalence of floor heave, the absence of strong structures at outburst sites, the possibility of outburst at any stage in pillar formation up to the last few yards, the effect of rate of advance on outburst occurrence, and the mildness of many outbursts experienced.It is concluded that inducer shotfiring is a reliable control but it suffers by comparison with outburst-free conditions, and that control by preyention would be preferable.INTRODUCTIONThe phenomenon of instantaneous outbursts of coal and gas has been described in detail previously (Hargraves, 1958). Briefly, it is a combined gas and stress hazard of deep coal mining, usually occurring in virgin work and during active face advance, when coal and seam gas burst from the face into the workings.Instantaneous outbursts have occurred sporadically at Metropolitan Colliery, N.S.W., since 1895. Early outbursts were recorded as firedamp and recent outbursts are of blackdamp.Mining methods used have been conventional hand work, with progressive and relatively complete mechanisation over the past 25 years to substantially conventional...

Jan 1, 1964

The discussion in this paper centres on examples of mining that are drawn mainly from the coal mining industry. The intention is to review the opportunities that exist for incorporating environmental planning into mining industry practice in New Zealand. The coal mining examples serve to make some general points which have some application for many types of mining.

Jan 1, 1981

By A Jewbali, J Phillips, C Boyle

Normal practice in the mining industry is the creation of a single geological model. These models provide a single interpretation of the geological and mineralisation domains. These interpretations infer the exact behaviour of ore domain contacts at shorter scales when resource definition drilling is done on wider scales and are thus locally highly uncertain. The interpreted geological model provides a single number for the volume and tonnes of mineralised material enclosed by the mineralisation envelope. It is on this single number for volume and tonnage that capital intensive mine development decisions (mine design and scheduling, stockpile strategy, waste management, closure planning, dewatering strategy, product quality, etc) are based. Some of these decisions require knowledge of grade variability for small volumes of material such as quarterly production periods. It is generally recognised that this information cannot be derived from single kriged geological models, but can potentially be modelled by conditional simulation techniques. Uncertainty in the extent and continuity of the mineralised envelope and its effect on grade variability for shorter production periods is thus recognised as a major source of uncertainty in new mine development.CITATION:Jewbali, A, Boyle, C and Phillips, J, 2013. Quantifying domain uncertainty for an iron ore deposit, in Proceedings Iron Ore 2013 , pp 157-168 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Kudremukh Iron Ore Company Ltd, a wholly owned Government of India Enterprise, was established in the year 1976 to develop mine and plant facilities to produce 7.5 Mtpa of high-grade iron ore concentrate at Kudremukh. The mine and plant facilities were commissioned in 1980. In view of high demand for iron oxide pellets in iron and steel industry worldwide and as a diversification activity, a pelletisation plant of 3.0 Mtpa capacity was commissioned in the year 1987 at Mangalore for production of high-quality blast furnace and direct reduction grade pellets for export. The pellet plant capacity has been increased to 3.5 Mtpa by technological improvement which included installation of roll press for quality and productivity improvement. In addition, the pellet capacity is being increased to 4 Mtpa by the addition of Shaft Pelletising Furnace plant.

Jan 1, 1999

By G Eastwood, C Joyce, P Ryan, G M. Johnston

Over the years, predictive techniques for Acid Mine Drainage (AMD) and the natural processes affecting acid generation have received considerable attention. Less emphasis has been placed on the sampling strategy and the integration of testwork results with the geological data base. The sampling strategy employed and the development of a geological model to determine the spatial distribution and volume of acid producing material are often crucial for developing cost-effective containment and mitigation measures. The geological model provides a link between the occurrence, timing, destination and placement of mined waste rock. Careful and accurate interrogation of a comprehensive geological database provides this linkage. The AMD testwork program at Cadia in NSW has been designed to identify the temporal selective handling requirements that will be required during operation. Sampling involved collection of representative combinations of all waste rock types identified within an extensive geological database. These samples were subjected to static, kinetic and accelerated weathering predictive tests. Preliminary results have been used to construct a waste block model for the deposit that identifies the quantity and distribution of acid producing material. Integration of the block model with the mine scheduling determines when the material will be mined.

Jan 1, 1996