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An underground storage and filling distribution system is presently being established at North Broken Hill Limited in the No.3 Shaft area. This has been necessitat- ed by the dependence of the present filling system on the No.2 Shaft and its imminent closure due to cessation of production. The storage will consist of three tanks excavated in low grade ore, between the No.20 and No.21 levels, at approximately 2700 feet below the surface. The tanks will each have a capacity of 1500 cu yds. Consideration was given for surface storage, although under- ground storage was thought to have greater merits. Two tanks have been excavated, and are in operation. Three or more outlets are installed beneath each tank, with horizontal connections into the No.21 level 'mixing box'. Water decants from the top of the fill in the tanks, and passes into a decant water sump, at the bottom of which is a borehole to the No.21 level. This is then connected to the mixing box and water used as make-up water with the semiwet solids for transport into the existing pipe distribution system. Preliminary results of the system have been satisfactory and it is envisaged that this system will readily cope with the filling demands of the future.

Jan 1, 1973

By H Mischo, G Barakos, J Gutzmer

The continuously growing demand for rare earth elements (REEs), in combination with the crisis of 2009 and the price spike of 2011, has initiated a treasure hunt for rare earth deposits all over the world in recent years. Since then, commodity prices have declined and are now quite stable, yet the world is still dependent on China’s dominance of the market and its export policies. Exploration is unremitting and numerous resources of potential interest have already been revealed in many countries; however, proceeding to mining operations is not that simple, especially when it comes to the exploitation of rare earth deposits. Evaluating the feasibility of a mining project is always a unique, sensitive and rather complex process that depends on multiple criteria.This paper focuses on clarifying the present and future global situation in the development of respective deposits and on identifying rare earth-specific criteria that influence the overall feasibility assessments of any potential (especially underground) mining projects. Environmental impacts, legislation issues and the presence of radioactive pollutants are some of the notable boundary conditions that govern rare earth mining operations and need to be taken into consideration. Furthermore, the balance problem between the supply and demand of the different REEs can determine decisively whether a deposit of specific REEs is economically exploitable. For this reason, evaluations are made regarding the future strategies to be enacted in order for the rest of the world to detach itself from this situation. The ultimate goal of these evaluations is for them to be incorporated in an overall assessment tool for rare earth underground mining procedures that will be implemented in real case studies to determine their sustainability.CITATION:Barakos, G, Mischo, H and Gutzmer, J, 2015. Status quo and future evaluations of global rare earth mining (with respect to special rare earth element-industry criteria), in Proceedings Third International Future Mining Conference, pp 21–30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Haskard R. W

A method of raising has been developed at Cobar Mines Pty Ltd's CSA Mine which has achieved advance of up to 6 m in a single blast and raises are now developed which have averaged 4.2 m per blast. The method is a form of Long Hole Raising and is applicable to short raises of less than 50 m length. Blast holes are column charged and initiated sequentially with short delay detonators (millisecond). The equipment used to drill the raising blast holes consists of normal production drilling rigs and accessories and no other special equipment is required. The method has significant advantages in rates of performance and fits neatly into production drilling and blasting schedules. The method is also far safer than any non-mechanical or conventional means of Raising.

Jan 1, 1983

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

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

Oct 16, 2017

Western Mining Corporation has grown from a small gold exploration and mining company, funded by large established mining companies, into a large multi-commodity and multi-national mining company with shareholders who no longer have the same understanding of mining as the founders. Ore reserve calculation methods and reporting procedures have gradually changed throughout the group during this growth. These changes have been led by the newer mines, in particular the Kambalda nickel mines, where the need for more global, less conservative reserves were required to justify capital and forward sales contracts and to inform shareholders of the true worth of their company. This change in attitude to reserves has flowed back to the gold mines and has allowed a better informed management and investing public to plan for the future. Management of the calculation of reserves remains the responsibility of individual mining operations, but a corporate reporting and management structure exists through the office of the Director of Exploration and divisional chief geologists who strive to maintain standards of calculation and reporting. Specialist ore reserve geologists are starting to justify their place in the organisation, particularly at the larger operations. Reporting to the new AusIMM Standards is fully supported, although the amount of supplementary information requested will need to be considered carefully because of the large number of factors that make up even the simplest reserve.

Jan 1, 1990

A minimum target of economic growth in Australia has been set at 5% per annum growth in G.N.P. at constant prices (Vernon Committee). 2. The core of the problem of sustaining steady growth at this or a similar rate is to ensure regular flows of investment. This sustains productivity, helps to control balance of payments pressures, and to check inflation. 3. The regular intake of human and physical resources, in conjunction with intensive capital development involving finance, technology and management, is basic to sustaining the growth rate and ensuring rising standards of living.

Jan 1, 1971

A new test coke oven of seven cubic foot capacity is described. The oven was designed to simulate conditions in a central section of a battery oven and a special feature is the achievement of unidirectional heating from the flues on either side of the charge. The method of charging permits close control of charge conditions'such as bulk density and moisture content. These conditions, as well as coking conditions (e.g. flue temper- atures., coking time) must be varied to simulate conditions in different batteries, The effects of several variables on coke quality are discussed. Using test oven conditions corresponding to those of Newcastle steelworks batteries, good agreement was obtained between strength indices of test oven and battery cokes; for 17 tests, the average A.S.T.M. stability and hardness indices for the test oven coke were 38,5% and 69.7%, while those for the battery coke were 37.1.% and 67.6%.

Jan 1, 1969

By Wright G. A

The objective of refining in steelmaking is to reduce the concentration of impurity atoms, e.g. sulphur, phosphorus, from an initially high level to a specified low concentration. A two-film theory of refining is presented in which the rate of

Jan 1, 1980

By Sen A. K

The Chiria Iron Ore deposit falls within the well-known Horse-shoe-shaped Singhbhum-Bonai-Keonjhar belt in India, where most of the deposits supplying ore to various steel works of Steel Authority of India Limited (SAIL) and Tata Iron and Steel Company (TISCO) are located. With an estimated reserve of about 2000 million tonnes of ore (at 55 per cent Fe cut-off) spread over four contiguous blocks, it is the largest iron ore deposit in India and one of the largest in world. The present study is confined to only one of the four blocks of Chiria viz North Block, comprising an area of 2.11 km2. `Corporate Plan 2005' of SAIL envisages development of a large open cast mine at Chiria to meet its enhanced requirement of iron ore by 2001-02 AD.

Jan 1, 1995

By M Malec, J Szczerbinski

Hazards in underground mines are concomitant with the mining of mineral deposits and have their source in a minerÆs work environment. The authors of the paper have undertaken a trial classification of these hazards into three groups, depending on the sphere of their occurrence:lithosphere, ie rock mass, atmosphere, ie air in mine workings, and technosphere, ie machines, equipment and facilities in mine workings. The lithosphere creates such hazards as bumps, rock outbursts, the atmosphere is a factor causing fires, methane explosions and climatic hazards, whereas accidents concomitant with an operation of machines and equipment occur in the technosphere. Assuming that the number of accidents in the mining industry, concomitant with hazards, reflects the degree of safety, it has been shown, that in Poland they are under control to a large extent.

Jan 1, 1999

The South Junction deposit of St Barbara Mines Limited was discovered in 1989 by the geologists of Ross Atkins Mining.The deposit occurs in the lower part of the Gabanintha Formation of the Lukes Creek Group in the Mt Magnet -Meekatharra greenstone belt. Country rock is predominantly talc-chlorite schist. Gold mineralisation is associated with north-south shear zones, quartz-carbonate-fuchsite alteration of the ultramafic rocks and in particular close to deeply weathered quartz-albite porphyry. For a detailed description of the geology of the South Junction Deposit see Fiala (1992).

Jan 1, 1993

By Abbott T. M

Alcoa of Australia operates three Alumina refineries in the South West of Western Australia at Kwinana adjacent to the South suburbs of Perth and at Pinjarra and Wagerup in rural settings 100 and 150 kilometres south of Perth respectively (see Figure 1). Alcoa's total alumina production is currently around five million tonnes per annum and this will increase to 5.5 million tonnes by early 1990. Further expansion of production is likely if current world aluminium demand trends continue. Alcoa's refineries utilise bauxite mined in the nearby Darling Range which is low grade by world standards having around 32 % by weight extractable alumina (by comparison Weipa bauxite yields around 55% alumina). This means that for every tonne of alumina produced two tonnes of solid wastes remain and therefore while we in Western Australia can boast of hosting the largest alumina industry in the world with around 18% of total world production we suffer from having the lion's share or 40% of the world's bauxite residues to dispose of. In its Western Australian setting the management of these residues in a manner which is acceptable to the community creates many challenges. These are primarily due to the mass and volume of waste produced, its chemical and physical characteristics and the environmental features of the local area including close proximity of neighbours, competing land uses and the presence of natural resources such as surface water and groundwater. In addition the trend towards more stringent statutory environmental controls and greater political and community awareness of environmental issues means that we must be able to demonstrate improvements that will reduce the considerable adverse impacts of past practices. Of course we must also try to keep the overall cost of residue disposal as low as possible to maintain our competitiveness with refineries which may have much smaller volumes of waste to dispose of and less environmental constraints.

Jan 1, 1989

Revegetation at Perseverance Mining's Nagambie Gold Project is an excellent example of cost effective revegetation in the Central Victorian Goldfields. Work has centred on waste rock dumps, vegetative screens, amenity planting and revegetation trials on cyanide heap leach pads. A wetland is under construction and in consultation with farmers, waste heaps were planted with perennial pasture species.The area treated to date is 18 hectares comprising: 16 hectares of pasture and two hectares of trees/understory. Direct seeding and tubestock planting has cost $16,464. Cost effective revegetation demands careful planning from the EES stage onwards. The Government agreed rehabilitation plan should be comprehensive, realistic and above all flexible. This document must be kept in mind during the mining operation.

Jan 1, 1992

The Kennedy Siltstone Open Cut provides graded rock for stope filling. Rotary drilling of 310 mm blastholes with a Gardner Denver GD120 is used, and the successful application of an equilateral triangular drilling pattern is described. Charging practices and the development of bulk slurry handling are outlined. Blast monitoring plays an important role in K.S.O.C. drilling and blasting operations. The proximity of nearby residential areas (1300 m) and the Mount Isa Airport (4500 m) necessitates special attention with regard to the minimisation of both air blast and ground vibration levels. The application and control of drilling and blasting parameters has had a direct bear- ing on success of the mining operations and also played an important role in reducing the disturbance to the community.

Jan 1, 1978

By Plumridge C. L, Lynch J. E, Forresty R. J

The Amanda Bel Goldfield (new name) is an area of approximately 1000 sq. km centred 65km WSW of Ingham and 150km due east of Kidston (Camel Creek homestead to Ryeburn homestead area). Gold mineralisation has been located in tightly folded sediments of the Silurian Greenvale Formation as well as in the Early Devonian Kangaroo Hills Formation and the Early Carboniferous Clarke River Formation. The area is traversed by a major NW-SE structural corridor, with many of the numerous basaltic, andesitic and rhyolitic dykes of the region sharing a similar trend. So far fourteen gold-bearing zones have been located, all of which are new discoveries delineated by bulk cyanide leach sampling and subsequent geological reconnaissance. The region has undergone three periods of deformation with gold mineralisation introduced syn-D1, post D1 - pre D , syn-D and post-D2/D , thereby revealing an involved metall~genic history. Mineralisation types include Sb, Sb-Au, Sb-Au-As, Sb-Au-As (-Pb-Zn) and Au-As. Minor occurrences of W, Pb-Zn-Ag and Pb-Zn-Ag-As-Sn are also present as are alluvial (deep lead) tin Drosoects.

Jan 1, 1989

By Qi P. H

Gold dissolution can be achieved with a number of complexing ligands, all with varying degrees of stability. Processes based on the use of halogens have been known for many years. Beside providing the necessary complex- ing role, the halogens under the appropriate conditions are very effective oxidants for gold. Of the halogens, the gold iodide complexes are the most stable in aqueous solution. Iodine can establish the desired oxidation poten- tial for oxidizing gold, and unlike chlorine and bromine, the oxidizing potential of iodine is mild enough to avoid the oxidation of impurity constituents like metal sulfides. A series of experiments to investigate the fundamental electrochemistry of gold in different halide solutions was performed. Cyclic voltammograms of gold in the presence of 10-2 M chloride, bromide and iodide, respectively show that for a given potential the rate of oxidation is much faster in iodide solution than in either chloride or bromide. An overlay of linear sweep voltammograms for the anodic oxidation of gold in iodide and the cathodic reduction of iodine species on gold provides an effective method for examining the dissolution of gold in iodideftodine solution. The dissolution rates obtained from both electrochemical and actual leaching results are compared. Optimum leaching conditions are analyzed in terms of the iodide/iodine concentrations. Conceptual processes for the recovery of gold and iodide and the regeneration of iodine are discussed.

Jan 1, 1991

By Yianatos J. B

The advances in the study of control alternatives for flotation columns are reviewed. An integral solution to the control problem has to deal with problems associated with instrumentation, process modelling, control strategies and control algorithms. The term hierarchical control is used here to mean the intelligent integration of available knowledge, control algorithms and logic rules of decision. The selection of information, algorithms and rules is based on the experimental and theoretical knowledge of the column flotation process. The software support was designed and implemented in object oriented computer programs. This technique allowed the implementation of a combination of control techniques, algorithmics and heuristics, in the form of a control strategy. This strategy has shown to fit well with processes exhibiting complex dynamic characteristics. The hierarchical control was implemented in a pilot column and included the following general aspects: co-ordination of distributed conventional control loops, use of sets of control parameters for the froth depth control loop according to the froth depth state, verification and diagnosis of sensors, on-line predictive estimation of gas hold-up, diagnosis of common operating problems and the use of predictive control to account for feed flowrate changes.

Jan 1, 1995

Five Hypotheses are given for factors influencing long-run metals price forecasts. 1 . Geologists succeed when given the money. 2. Better understanding of a metals market depresses its price. 3 . Statistical techniques get forecasts wrong. 4. Long-run metals prices are related to crustal abundance. 5 . Economic cycles affect metals prices more than is realised. These are then framed within the transition between eras as influenced by apparent long waves in economic activity. Innovation surges during the transition between eras. The transition to the 5th Wave since the Indus- trial Revolution 200 years ago is now underway. Finally, price projec- tions are given both for the 5th Wave and 200 years from now on the assumption that a similar monetary measure to today will be then extant.

Jan 1, 1988

By Stewart W. J

The volumetric method of estimating hydrocarbon resources and recoverable reserves is and probably will remain a dominant method in petroleum engineering. The method is technically very simple, but has one main problem: how to express, measure and properly handle the variable and complex uncertainty of each estimate. The computer age brought in the Monte Carlo Simulation method which enables correct arithmetic operation using data with specified probability distribution. However, several problems are still not solved uniquely and still exist. For instance, the determination and description of the distribution of single parameters, the determination of the degree of dependency between parameters (e.g. hydrocarbon saturation-porosity), and standard probabilist- ic definition of generally used categories (e.g. proved, probable, possible). Methods for handling these problems are discussed.

Jan 1, 1979

By Pinter R

Several major routes connecting Northern and Southern Europe or Asia run through Austria. These highways have to surmount the alpine range which traverses Austria from west to east. In order to ensure safe driving conditions even in winter, tunnels, at times quite long ones, are necessary. Austria now has tunnels totalling 160 km in length. These tunnels are either already in use or just about completed. The Plabutsch tunnel near Graz will be one of the longest tunnels in the world: approximately 10 kilometers in length. It will be put into operation in the summer of 1987. Before construction could begin, soil and rock conditions had to be investigated by means of a test tunnel. Afterwards, excavation was begun to the full 100 m' cross section. The new Austrian tunnelling method with conventional blasting was used for the major part of the tunnel. It was necessary to have such a large tunnel cross section because a fully transverse ventilation system is installed for environmental reasons. In order to avoid air pollution from the tunnel, exhaust fumes are not allowed to escape from the tunnel portals but from two shafts, each with a diameter of 8.5 m. In this way, exhaust fumes must rise 90 meters or 240 meters before they reach the open air and will thus not affect the city. The ventilation system influences the size of the excavation, and especially the size of the ventilation caverns and the air shafts. All these factors directly influence construction and maintenance costs, and an economical optimisation leads to the appropriate dimensions for the excavation.

Jan 1, 1987