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It is not often that mines have as much warning of the approach of bad ground conditions as was the case at the Western Mining Corporation, Kambalda Nickel Operations Lafranchi/Schmitz Decline. Most aspects of this operation are in fact quite unique and like the best solutions, the answer to the problem of weak and foliated ground conditions was relatively simple; requiring the use of readily available explosives although the idea of using it in this manner may not be the most obvious.The use of high shock energy POWERGEL 2131 cartridges proved to be the correct answer, in conjunction with small changes in drill pattern design. The resulting lack of overbreak bears testimony to the success of the concept and the commitment of the miners to achieving a safe working environment.

Jan 1, 1992

The Douglas mineral sands deposit is located 75 km north of Hamilton in western Victoria, Australia. The deposit was discovered in the late 1990s by Basin Minerals Limited and purchased by Iluka Resources Ltd in 2002. Prestrip mining commenced in December 2004, with ore mining commencing in August 2005. Douglas is the first of several projects being implemented by Iluka Resources Ltd in the Murray Basin, with all heavy mineral concentrate planned to be treated at the companyÆs mineral separation plant in Hamilton. The mineralisation at Douglas lies along the south-eastern margin of the Murray Basin. It is hosted by marine Pliocene Loxton-Parilla Sands and consists of three discrete deposits; Bondi Main, Bondi West and Bondi East. The mineralised sediments dip at a low angle to the west and lie unconformably beneath a veneer of top soil (50 - 100 mm) and subsoil (up to 600 mm) and between three to 12 m of overburden. The barren overburden, characterised by high clay content (<53 ¦m material) generally provides a stark contrast to the sandy ore, which is between 1 m (parts of Bondi East) and 15 m (Bondi Main) thick. Both overburden and ore are removed utilising standard dry mining techniques using both scraper-bulldozer and truck-excavator combinations. All ore is delivered to run-of-mine (ROM) stockpiles before being reclaimed by front end loader into the processing plant. Grade control at Douglas is based around visual dig control aided by high precision survey, which enables accurate reference to the resource drilling and block model data. Vertical excavator faces, inclined scraper faces plus regular test pits and trenches provide opportunities for in pit mapping and sampling. This data is used to refine not only the resource estimate for Douglas but also the drilling, interpretation and resource modelling methods used for similar deposits across the basin. The foundations of the geological reconciliation process at Douglas are the in pit surveys undertaken each time the mining fleet has completed building a ROM stockpile. These surveys and the subsequent interrogation of resource models enable robust estimations of the heavy mineral content of the stockpiles, which are subsequently used to predict the daily input grades into the plant during their reclamation. Reconciliation of this daily data is then undertaken at the end of each month against metallurgical production data and plant balances. Learnings and results from the reconciliation process are used to further refine subsequent resource models and modelling methods.

Jan 1, 2009

Industry can achieve best results via thorough planning, consultatiion with agencies and local communities and a 'hands on' approach to' environmental problem solvingThe Department of Energy and Minerals, through its Minerals Group, has regulatory responsibility for the mining and extractive industries in Victoria. The role of the group is to facilitate the environmentally responsible development of these industries for the benefit of Victorians. It has a wide range of contacts with other government agencies, local government and community groups.The paper is in three parts; firstly, an overview of the nature and contribution of the mining and extractive industries in Victoria; secondly, the industries' regulatory framework; and thirdly, the environmental issues facing the industries and the management of these issues.

Jan 1, 1992

By Peck W

The tunnel alignments investigated for the Gosford Regional Sewerage Scheme are located in the Terrigal Formation and are covered for most of their length by a thick blanket of soil and weathered rock. The following techniques were found to be most effective in geotechnical investigations for tunnelling in this area: air-photo interpretation, seismic surveys to pinpoint drilling targets, in-situ measurements of strength,deformation modulus and permeability in cored holes, and the construction of rock- mass models. Cross-hole seismic modulus measurements, surface resistivity soundings and electric well-logging techniques were found to have limited applicability due to adverse local conditions.

Jan 1, 1976

By D Adhikary, M Khanal, B Poulsen, H Guo

During longwall mining, the ability to reliably estimate the height of longwall mining-induced fractures is critically important in order to effectively manage mining-induced water inflows and aquifer interference. The extent of mining-induced subsurface deformation, fracture, surface subsidence and aquifer interference is largely controlled by local lithological conditions, mining methods and mine layouts. Therefore for the purpose of quantifying mining impacts it is imperative to incorporate the local geology and mine plan parameters in a mine scale model. Two different numerical models based on 3D continuum (Finite Element Method) and 2D discrete (Discrete element method) domains, respectively, are developed to incorporate the mine site parameters of a study site in Australia. Both the models are calibrated and validated with measured mine data. The continuum numerical modelling method is used to investigate the change in permeability of the overburden strata due to underground extraction considering the full 3D nature of geology and mine layout. The discrete element modelling method is used to simulate the initiation and propagation of fractures, allowing the caving of overburden strata to be represented in a realistic manner, and the permeability enhancement of the strata overlying the goaf to be calculated from first principles. Permeability enhancement in the discrete element model is a direct function of the fractures induced in the deformation/caving process; fracture location, extent, aperture and connectedness. From the numerical modelling under the simulated condition for the mine studied here, it is predicted that the permeability of the caving zone from the goaf to five times the mining height increases by almost six orders of magnitude. In the fracture zone to approximately ten times the mining height, the change in permeability is predicted to be around two to three orders of magnitude. At the height of more than ten times the mining height the magnitude of permeability increased is predicted to be one to two orders of magnitude. CITATION:Khanal, M, Poulsen, B, Adhikary, D and Guo, H, 2018. Modelling of height of connective fractures during longwall mining, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 254–265 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

The Gympie Goldfield was the sixth largest producer of gold in historic terms in Australia. The Joint Venture Agreement between BHP Gold Mines Limited and Devex Limited was signed in January 1987. Since that time, some $20 million have been spent on underground and surface exploration work in the southern portion of the goldfield. The project is of considerable interest as the dewatering, rehabilitation and equipping of an old rectangular timber-lined shaft has been undertaken. The project is located in Gympie, a city of 10,000 people. The issues of dealing with urbanisation and associated environmental aspects are vital to the success of the project. An outline of the project and the geology of the mineralised structures follows:

Jan 1, 1989

By R van Berkel, J Lay, D van Beers

The development of regional resource synergies in intensive areas with concentrations of minerals processing industries provides a significant avenue towards sustainable resource processing. Gladstone (Queensland) and Kwinana (Western Australia) are two of AustraliaÆs major heavy industrial areas. There are a number of successful regional synergies in both areas. In addition to the existing regional synergies in both areas, more potential synergy opportunities appear to exist which, upon implementation, could benefit industry, the environment and the community. To further enhance the development of such potential regional synergies, the Centre for Sustainable Resource Processing (http://www.csrp.com.au) commissioned research projects to facilitate the identification of potential synergies and assist with their implementation in both regions. This paper presents a selection of specific examples from both regions to illustrate the sustainability benefits from regional synergy developments. Although the composition of industries in the Gladstone and Kwinana regions is different both in terms of geography and industry diversity, similarities in synergy developments for both regions are apparent. Consequently, the examples discussed in this paper are organised around the key themes of water, energy and inorganic by-products. Comparison on a theme basis highlights success factors of successful synergies and demonstrates the range of benefits resulting from their implementation.

Jan 1, 2006

The completion of the Hot Strip Mill at the Port Kembla works of Australian Iron & Steel Ltd., makes possible the production of steel plates and wide strip of a quality and in quantities not possible previously in Australia, and will also enable the production of tinplate to be undertaken in this country.The site chosen for the mill was a mud fiat underlain by a hard stone bottom at 5, to 801 feet below the surface; and a total area of one hundred acres was reclaimed to a level of 20 feet above the original surface.Three adjoining buildings were constructed to house the slab receiving yard, mill equipment and electric drive, together with the plate finishing line.After slabs have been heated to 2250°F at a rate of 90 tons per hour, they are transferred to the vertical scale breaker which is the first stand in the hot roughing mill. Here the primary furnace scale is first cracked and then blasted off by high velocity water descaling sprays.The next stand is the horizontal scale l;Jreaker, where any remaining primary scale is broken and then blasted off. After descaling, the slabs pass to the broadside mill, where short slabs are turned and rolled on broad side for wide plate.The next step is a slab squeezer which squares up the edges after broadsiding ready for the reversing mill. This is the finishing stand for plate and the last roughing stand for strip, which then passes to the finishing mill.The hot strip finishing mill consists of six stands with a maximum finishing speed of 2,230 feet per minute. Strip is cooled for coiling by water sprays on a hot run table and then coiled on a mandrel type downcoiler, from whence coils of hot strip are weighed and transferred by conveyor to the coil storage building.Plates are transferred from the reversing mill to the plate finishing line where operations consist of levelling, inspection, branding, cutting to width and length:INTRODUCTIONDue'to the increasing production of cars, refrigerators, washing machines and similar consumer goods in Australia, together with the increased requirements of galvanised iron...

Jan 1, 1956

By Burford B. D, Johnson N. W, Rohner P

Under design philosophy, the Hilton concentrator produced lead, zinc and LGM (lead plus zinc) concentrates. The LGM (Iow grade middling) concentrate was produced by combining coarse middling streams from the lead and zinc circuits, regrinding and subsequent flotation. Mineralogical examination of the zinc circuit middling stream prior to regrinding suggested that production of zinc concentrate from the zinc circuit middling stream should be possible by rearranging existing plant equipment. Laboratory testing of samples of plant products, however, showed that regrinding combined wi th the usual reagent suite was nO1 sufficient to produce a zinc concentrate of the required specifications.Examination of the process water highlighted a problem with dissolved salts in the circuit water, which was solved by in-circuit precipitation of the dissolved ions with soda ash. Implementation of the procedure in the concentrator effectively transferred to the zinc concentrate all sphalerite previously recovered to the LGM concentrate.

Jan 1, 1994

Integrated geological interpretation of aerial photographs and Landsat images revealed that the gold mineralisation at Kyauk Pahto took place in a narrow zone of tension fractures within part of a previously unrecognised dextral wrench fault system. The latter is the wider manifestation of the well known Sagaing (right-lateral) strike-slip fault which has a length of more than 1 000 km, and it demarcates the boundary between the Indo-Australian and Asian plates. A subtle, right-handed kink affects the full width of the Sagaing Wrench-fault System at about the latitude of Kyauk pahto, and the extra dilatancy imposed on the tension fracture zone facilitated episodic ingress of mineralising hydrothermal fluids by "seismic pumping".

Jan 1, 1987

By Larsen D. F

Minor iron formation related base metal sulphide mineralization occurs in granulite facies metamorphic rocks of the early Proterozoic Willyama Complex. Rock sequences hosting three iron formation related Cu, Zn, Pb prospects from the Thackaringa Group (Suite 3) are described. A caparison of host rock sequences, style of mineralization and facies of iron formations suggests major differences in terms of the overall depositional environment. However, significant similarities are present with respect to the nature and distribution of iron formation facies and the occurrence of chlorite 'alteration' zones in close proximity to mineralization in all cases. The chlorite within these zones occurs in a number of diverse forms in a range of rock types. A comparison of the prospects shows that there is no evidence to indicate that the chlorite in the zones is a retrograde alteration product of former higher grade prograde mineralogies - the chlorite appears to have survived granulite facies metamorphism. The mode of occurence of the chlorite in the 'alteration' zones together with the fact that the association quartz + chlorite + magnetite + pyrite + base metals is cx rmn to all areas suggests that the chlorite is specifically related to the processes which deposited the stratiform iron formations and related sulphides. It is considered that the chlorite precursor was a prenetanorphic alteration product or chemical sediment closely related to submarine hot spring activity which was also the source for chemical sediment precursors of the iron formations, associated lode rocks and Sulphides.

Jan 1, 1983

By Hossaini SMF

The applicability of four empirical strength criteria for rock masses, namely, Hoek and Brown, Bieniawski - Yudhbir et al., Ramamurthy - Arora and Johnston - Sheorey et al. has been tested against the triaxial test data for jointed plaster of Paris of Arora. The following modified Bieniawski criterion shows best agreement with the triaxial test data for jointed plaster of Paris: 611=1+B(63)O.825 acm 6cm where a1= axial compressive stress at failure, MPa; a3 = confining pressure, MPa; acm = uniaxial compressive strength of jointed plaster of Paris, MPa; and B = - 3.988 + 9.674 (aim ) -0.185 The modified Bieniawski strength criterion can be used to estimate the strength of a coal pillar, based on a knowledge of stress distribution in it.

Jan 1, 1992

Most types of nuclear power reactors use uranium dioxide fuel. Power reactors using natural uranium dioxide'fuel are of special interest to countries such as Australia that have their own uranium supplies. A wide range of uranium dioxide powders can be fabricated and the ideal one flows readily, presses without the need for binders or lubricants, sinters to the required density and gives low reject rates at all fabrication stages. Sinterable uranium dioxide is usually produced via the ammonium diuranate route. The A.A.E.C. is aiming to demonstrate production of nuclear grade uranium dioxide from Australian concentrates, improving technology where possible. Details are given of the dissolution, solvent extraction, precipitation, filtration, drying, and calcination-reduction steps. Solvent extraction from sulphate media is also under study with a view to developing a process to produce a nuclear grade product at the mine treatment plant site,

Jan 1, 1969

By J St George

Much of AucklandÆs transport infrastructure has been developed on surface with little or no consideration of underground options. Current and planned transportation routes are now facing high costs due to land values and increasing environmental resistance to surface development. The option of utilising underground space becomes a feasible investment decision for these links as well as being the only option to develop the rail network within the inner city area. Transportation tunnels offer a quieter, more energy efficient means of getting around with minimal impacts on the surface environment. One of the major impediments to tunnelling is the high construction cost, which is partly related to the risks of encountering unexpected ground conditions and/or the possibility of causing surface ground deformations which could damage structures. The geology of Auckland has had substantial investigation through various studies and projects. The sediments of the East Coast Bays Formation (ECBF) underlie most of the Auckland urban area. It is classified as a soft rock and is a suitable material to tunnel through using either a tunnel boring machine or a roadheader. This paper reviews the limited amount of tunnelling completed in the urban Auckland area, together with the international advancements that have been made in the tunnelling industry. From the known features of the local geology and the problems encountered historically, the likely risks of tunnelling in Auckland are presented and ways in which those risks could be reduced and managed, are discussed. In addition, contractual arrangements between client and contractor are assessed with respect to complicated projects (such as tunnelling), so that the risks can be managed to create efficient infrastructure routes with reduced costs.

Jan 1, 2008

By Ward B

Central Colliery was developed to exploit large underground reserves in the German Creek lease. It was planned from the outset as a retreating longwall operation and is the first longwall mine in Queensland. Longwall mining is not new to Australia but all previous experience has been confined to the coalfields of New South Wales. There was no precedent for longwall extraction in the markedly different geological setting of the Bowen Basin in Central Queensland. Various investigations were thus carried out during the initial development of Central Colliery, prior to the installation of the longwall, to ascertain the geotechnical characteristics of the coal seam and the adjacent strata and to predict the performance of the heading and pillar design as mining proceeds to depth. Laboratory tests showed the coal to be weak with an unconfined compressive strength of 9.6 MN/m2. Site inspection and geophysical correlation revealed a shear zone and extensive intraformational shear planes in the seam. The latter were found to exert a controlling influence on rib reaction in the headings. This behaviour was predicted by finite element modelling of the development headings which indicated that mining induced stresses in the coal would be relieved by block movement of the ribs. A chain pillar width versus depth curve was established for yielding pillar design based on empirical and computational methods. This gave pillar widths from 25m to 48m over the proposed depth range of 150m to 300m. Finite element modelling of the 25m pillars chosen for the first gateroads confirmed the overall stability of the design but suggested that rib spall could be significant in the adjacent tailgate. (1) Chief Mining Engineer, Capricorn Coal Management Pty. Ltd., German Creek Mine, Queensland (2) Senior Engineering Geologist, Coal Division, The Shell Company of Australia Limited, Melbourne

Jan 1, 1986

Samples weighing 0·5 g are fused with potassium hydrogen sulphate, leached with 4 ml. of 4 M nitric acid and diluted to 10 ml. with water. An aliquot of the clear solution is treated with EDTA, adjusted with ammonia to give a pH value between 5 and 6 treated with cyanide, ammonia, and sodium diethyldithiocarbamate then bismuth diethyldithiocarbamate is extracted with chloroform and the yellow colour is compared visually with a standard series. Alternatively, the bismuth complex may be filtered on a "Millipore" filter and subjected to x-ray fluorescence spectrometry.

Jan 1, 1971

On-line radioisotope gauges determine information on the characteristics of ore to enable improved control of processing operations. In the metalliferous mineral industry, in-stream analysis systems based on radioisotope X-ray techniques determine concentrations of valuable minerals at various stages of the concentration process. In the coal industry, on-line gauges determine ash and moisture contents, and the specific energy of coal.In-stream analysis systems developed in Australia are installed in about 30 mineral concentrators. Their use has led to the increased recovery of valuable minerals, and the time taken to recover the cost of installation is usually several months. The savings to Australia resulting from use of these analysis systems is estimated to be more than $A 15 million per year.Australian experience in the training of mineral industry personnel shows that the most effective approach is to combine courses on nuclear techniques and control of processing operations. This is the basis of Australia's contribution to the minerals sub-project of the United Nations Development Program (UNDP) Industrial Project.

Jan 1, 1985

By Wright R. J

The Commission called tenders for a four boom hydraulic jumbo, plus basket, on an art- iculated carrier in Sept. 1977. Atlas Copco submitted the successful tender in Jan. 1978 for the supply of a three boom jumbo, plus basket. The Promec TH470 jumbo was commiss- ioned in the 2000 m long Sophia tunnel in Nov. 1978. Adequate spare parts were not available during the first three months of operation and the hammers could not be overhauled at the recommended interval. One hammer was removed after drilling 13 600 m due to a crack in the intermediate housing. Tests were conducted with different types of drilling consumables. Both rope and Hi-teed threads were tested and found compar- able. The average penetration rate in the granite was 1.1 m/min. Initially the drillers were not experienced enough to operate the BUT 15ERH booms without causing damage to the booms and hoses. Drilling deviation espec- ially of the perimeter holes was greater than expected. It is now obvious that greater attention must be given to attracting, train- ing and retaining the right type of operator and maintenance fitter.

Jan 1, 1981

By M I. Pownceby, S P. Suthers, V Nunna, G J. Sparrow

Global demand for iron and steel has increased substantially over the past 20 years and there has been a greater focus on developing suitable processing options to treat low-grade hematite-goethite ores containing higher levels of silica and alumina impurities. The processing applicable to reduce the impurity levels in these lower-grade iron ores depends on their mineralogy and a thorough understanding of the process dynamics associated with the separation technology. Different separation technologies used to remove silica and alumina from low-grade iron ores were reviewed. The major concentration methods that may be applied to upgrade lower-grade lump iron ores include magnetic separation, wet and dry heavy media separation, and air-pulsed jigging. The technologies applicable to beneficiating iron ore fines include wet and dry gravity and magnetic separation, flotation, and roasting followed by magnetic separation. It is necessary to investigate the application of separation technologies on a case-by-case basis to select economically viable beneficiation strategies suitable for the particular low-grade iron ore. A commercial flow sheet is expected to involve the implementation of several separation technologies.

Nov 8, 2021

The phenomenon of Instantaneous Outbursts, although not new to Australia, was sharply drawn to the attention of the local coal-mining industry by two isolated fatal occurrences on widely separated fields, both late in 1954. An outburst is the eruption of apparently solid coal from the face, aided by vast quantities of gas released from the coal, as the coal fails under mining stresses additional to its natural stressing.The gases involved are principally methane and carbon dioxide. The various factors which combine to produce outburst conditions range from external factors such as stresses arising from depth of cover and other causes, to inherent factors such as strength of coal,and its capacity to retain gases (sorption). Of the localities where instantaneous outbursts occur the Gard Basin in Southern France has had the greatest number and the most serious occurrences. By contrast, local outbursts have been minor.Experimental work into some influencing factors has been carried out by various overseas authorities and some research has been accomplished in Australia. Practices used in some overseas areas to improve safety of working are largely empirical, as are the local rules and recommendations for work in affected areas.The appearance of further outburst areas is anticipated as mining becomes more extensive and deeper.INTRODUCTION"Instantaneous Outbursts" can be described as violent eruptions of coal from the solid accompanied by considerable gas evolution. The projected coal is usually of small size, and a high proportion is pulverized, and may be carried and deposited over great distances by the gases, liberated from the outburst. This outburst coal is of bituminous to anthracitic rank, and the gas involved is essentially methane or carbon dioxide, or a mixture of both. Outbursts involving carbon dioxide are usually more violent and dangerous. The phenomenon is relatively unusual, being confined to probably sixteen known areas in the entire world, these areas comprising only portion of the coalfields in which they occur. Usually only one or two mines on each field are affected.

Jan 1, 1958