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The Bendigo goldfield is centred on the urban area of Bendigo (population approximately 60 000) in central Victoria, 130 km north west of Melbourne, Australia. Gold was discovered at Bendigo in 1851 and production continued through to 1954. The Bendigo goldfield is the second largest goldfield in total gold produced in Australia, after KalgoorlieÆs Golden Mile with a total production of 22 million oz. The geology of the Bendigo Field consists of a series of tightly folded, interbedded sandstone and shale sediments. Within the sediments the gold mineralisation is hosted in quartz reefs or ribbons closely associated with anticline axes and reverse faulting. The gold within the quartz reefs is typically both coarse grained and erratically distributed.

Jan 1, 2002

Its two years since we have presented at this conference and since that time we have made significant progress with our coal developments in New Zealand. In 2005 we held the Whareatea West exploration permit and had just completed the purchase of the Cascade mine. Today, in addition to Cascade and Whareatea we now have the Takitimu Mine, Eastern Coal Supplies, our coal blending and distribution facility in Timaru, prospecting permits at Ohai and Orepuki and an established customer base underpinned by the contract to supply FonterraÆs Clandeboye plant commencing in September 08. For this presentation I would like to take you through our purchase and development of the Takitimu mine.

Jan 1, 2007

By Kawatra SK

The incentive to control coal flotation circuits arises because of disturbances, from plant operating practices and variations in feed coal characteristics, which result in large amounts of fine coal being lost in circuit tailings streams and lower grade concentrates being produced. Additionally, the flowrates and compositions of con-centrates and tailings streams can have significant effects on dewater-ing brocesses. A universal control strategy for these circuits cannot be developed. Rather, three major groups of variables must be con-sidered during strategy development: coal characteristics; circuit design and operating practice; and the variables selected to control the process. The second. and third groups-are discussed in this paper and examples from studies in operating plants are presented.

Jan 1, 1985

Throughout industry in Australia, time lost through work accidents and illness is three times greater than strikes. In 1978 in New South Wales alone, 400 workers died, 125,000 were injured, 6,000 were indust- rially deafened, and 3,800 people died of occupational cancer. It has been estimated that less than 10% of workers injured make claims for common law damages. The figure is probably in fact much lower than that. However, common law damages claims are starting to become a boom industry and employers are only now starting to see the effect of the increase in Claims. I predict that within 5 years the number of common law damages claims made will increase dramatically.

Jan 1, 1982

By B M. Moudgil

Atomic force microscopy (AFM) has become an important tool for understanding the nano- to molecular scale mechanisms predominant in multiphase systems. In flotation research, the use of AFM holds promise for unlocking and establishing fundamental mechanisms, ultimately leading to significant advances in process performance. From measuring and characterising surface forces, the structure of molecules at interfaces, and nanoscale features on flotation media, AFM is a powerful tool that has only begun to impact flotation research. Highlights of advances made in the utilisation of AFM for flotation research at the University of Florida are given with an emphasis on interpreting the mechanisms behind calcium activation in phosphate flotation and the impact of nanoscale asperities on collector-born surface hydrophobicity.

Jan 1, 2005

Australia has a high level of research and development capabilities in government, industry and tertiary institutions. In the- remote sensing fields, we have developed a range of applications in geology, agriculture, infrastructure and environmental monitoring which are very cost effective and applicable to projects in the Asian and Pacific region. Support by the Department of Science through the Scientific Industries Steering Committee has enabled rapid penetration of this technological capability into projects with significant economic and financial benefits. It has also led to the opportunity for development of new sensors and processing systems, through collaborative projects with regional countries, which. will have applications in cloud covered, rainforest, and coastal tropical regions for geological and resource applications.

Jan 1, 1987

The alluvial diamond deposit in the Kimberley Region of Western Australia which became to be known as the Bow River Diamond Mine was discovered in 1982 by joint venture partners Freeport of Australia Inc and Gem Exploration and Minerals Ltd. Mining commenced in 1987. This paper describes the exploration programs and results from discovery to commencement of mining and reviews the public reporting of this process in the light of 1992 Ore Reserves Code (JORC, 1992). This case study illustrates the difficulties involved in resource estimation of alluvial diamond deposits. The study also shows that current reporting standards were, to a large extent, adhered to a full ten years before the diamond reporting section to the Code was formulated.

Jan 1, 1996

By Ellis CG

The N.S.W. Department of Mineral Resources commissioned its first Mobile Gas Laboratory in 1973.Although originally intended for diesel exhaust analysis, it has been progress- ively made more suitable for mine air analysis. Currently there are two upgraded units in operation. These laboratories have been used at the scenes of four mine fires, two mine explosions and three recovery operations. The authors' experience jointly covers all of these incidents. In this paper they recount the role of the Mobile Laboratory in each incident - including the difficulties encountered - and trace the development of these units to their present state. Future improvements are foreshadowed, and some comments offered concerning the likely future role of these vehicles in mine Emergencies.

Jan 1, 1981

Green policies have gained momentum since the 1972 Stockholm Environment Conference. The environmental movement has influenced political initiatives both in New Zealand and abroad. Governments and international institutions have addressed local, regional and global environmental issues with varying degrees of success. New Zealand so far has not supported the United Nations' call for sustainable development in a,consistent manner.New institutions and new rules for resource management mean there are opportunities to look after the land in different and more ecologically sensitive ways than has happened in the past.The increasing influence of regional councils in resource management planning will have important implications for mining and mineral exploration. These trends are discussed and possible future events outlined.

Jan 1, 1990

By Mould GR

Gas drainage has been practiced for many years mainly for safety reasons in various countries in Europe, in the U.S.A., the U.K. and Japan. Legislation has been developed to control the production, transport- ation and utilisation of methane and associated gases. Gas drainage is now being carried out at some Australian Collieries, but as this is a new venture little specific legislation is available. This paper briefly describes the drainage methods and legislation applied overseas, gives a brief history of gas drainage in N.S.W. and indicates the deficiencies of the present legislation. It outlines the approach to new legislation which will deal comprehensively with gas drainage operations and utilisation in New South Wales.

Jan 1, 1982

By Russell J

A sustained drop in the grade of Mount Isa lead-zinc-silver ore occurred in mid 1980. It was decided to increase concentrator throughput from 200 000 to 240 000 tonnes/four week period to maintain budget metal production. To achieve this increase whilst maintaining acceptable grinding and flotation performance, crushing plant final product size had to be reduced from 100%-13mm to 1000-11.2mm. The goal in the crushing plant was to achieve a 20% increase in throughput with a 20% decrease in the top size of the product. This was achieved by operational changes to improve plant availability and optimisation of the existing crushing and screening equipment Performance.

Jan 1, 1978

By Miller M. J, Bauer J. C

The continuous copper drossing process operated at Port Pine since 1962 has had limited copper removal capacity as determined by a maximum tolerable Cu/S ratio in feed and the level of sulphur in blast furnace bullion. Recent process development has been to overcome these limitations to meet increased copper throughput requirements. A sulphur addition system was developed and installed in August 1987. The system has capacity to increase sulphur input by over 150%, meeting the increased copper capacity requirement and also allowing independence from the upstream process for sulphur supply. Developments in process understanding have been applied within the limitations of the existing furnace design with a 10% increase in the maximum tolerable Cu/S ratio.

Jan 1, 1989

By Harper B

The mining industry has developed a comprehensive view of the need to have production personnel well trained in the use and maintenance of mining equipment. A strong commitment from the industry to this view has been instrumental in creating an efficient, profitable and productive industry based on modem production processes, sophisticated equipment and a multi skilled workforce. As the industry continues to develop, and the skills and knowledge needed by productive workers continues to expand, the training processes adopted by the industry will need to develop in parallel, not only making use of the latest advances in learning theories, instructional design and technology, but also using these knew ideas in more efficient ways.

Jan 1, 1998

In 1972, with the West Lyell Open Pit winding down, mining operations transferred underground. All development tunnelling until the end of the decade was carried out by a fleet of ten pneumatic Jumbos.A decision was made in 1980 to purchase an electric-hydraulic Jumbo and a second was purchased in 1982. Their introduction changed the face of development at Mount Lyell. Significant new demands were placed on main-tenance sections, particularly on electrical reticulation.Subsequently, two further electric-hydraulic Jumbos were purchased from Agnew Mining in 1984, and successfully overhauled and commissioned. As well, two electric-nydraulic production drilling rigs have been purchased. Only one of the original pneumatic Jumbos remains in service.

Jan 1, 1985

By Cox SJD, Kramadibrata S

One of the major causes of accidents and loss of production in underground mines is falls of ground.As mines go deeper, higher stresses are encountered and strain energy stored in the rocks is more likely to be released dynamically. This results in bumping in the rock mass around a stope or development face. Such noises and increasingly difficult ground conditions are obviously a warning of more serious problems ahead. The activity is collectively referred to as rock bursting.In Australia the mining of metalliferous deposits is taking place at increasing depths at Mt Isa, Broken Hill and the Eastern Goldfields and ground control problems with rock bursts has already been experienced at all three sites.

Jan 1, 1990

By Canning RL, Pritchard J

The surface treatment works in the Mount Isa Mines Limited copper stream consist of a concentrator and smelter with annual capacities of 5.6 million tonnes of ore and production of 155 000 tonnes of anode copper respectively. Both plants have been sites for process optimisation in recent years, the emphasis being to achieve productivity gains in each particular plant. The continued low real world prices for copper resulted in an in-depth review of the entire copper process stream. This indicated the need for developments within both the concentrator and smelter, and changes to operating strategy to ensure that the entire treatment stream could be optimised. The paper reviews these changes.

Jan 1, 1986

The need to estimate the block size distribution of a jointed rock mass is of great importance in the design of blasting rounds to attain a pre- established fragmentation. Other Geomechanics topics, such as ,hydraulic behavior of rock-masses, as well as the determination of their strength properties, also require the accurate prediction of a rock-mass composition in terms of block size taking in due account the three dimensional interference of joints and other geologic discontinuities. In this paper, a method for computing the block size analysis of a jointed rock mass is described, using as input the common geologic data (dip and strike) of fracture planes existing in a rock bench prior to blasting.

Jan 1, 1977

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

In early 1985, Bougainville Copper Limited commissioned an automatic truck despatch system to control its fleet of 44 trucks and 9 shovels. Productivity gains in the past have been the result of increasing equipment size then improving availabilities. The emphasis now is on improving the use of that availability and in particular for trucks, in reducing non-productive truck movement. A batch allocation computer based truck control system had been in operation since 1978, so to achieve the desired improvements it was necessary to move to an automatic dynamic control system. A description of the system installed is given, together with a review of how the project was engineered, the problems encountered and the results achieved to Date.

Jan 1, 1986

By P Mulvey, M Stuckey

"Inter-aquifer leakage due to fractures caused by coal seam gas extractions or longwall mining is an important issue for both the gas and coal industries. Currently, predicting stress induced macro-porosity associated with hydraulic fracturing, depressurisation via dewatering or collapse of overlying seams to infill a void left by longwall mining, is problematic. If fractures can be located the fracture can be sealed. Locating fractures is difficult. The non-geophysical approaches to locate fractures has been to consider the mixing of different waters, particularly that of more recent shallower groundwater with older deeper groundwater, via differences in radio-isotopes integrated with geochemical models to predict likely mixing of waters. This approach is applicable under appropriately complex settings; however, it is an expensive technique and is based on the assumption that the daughter isotopes are equally non-reactive which may not always be the case.Potentially a cheaper and faster technique is to consider integrating geochemistry (mineral weathering) and hydrogeology. The chemistry of groundwater, controlled by the weathering of primary rock?minerals and?formation of secondary minerals, can not only be differentiated between geological strata but also within strata as different stages in weathering results in differing impacts on water quality (ie different reactants).Field analysis of pH, electrolytic conductivity (EC), oxidation reduction potential (ORP) and dissolved carbon dioxide together with laboratory analysis of dissolved constituents characterise the chemistry of the water. Collection of rock samples at the time of drilling for bore installation can provide the (only) opportunity to assess the media in which the groundwater resides and migrates through. An assessment of aquifer matrix chemical makeup, via bulk sample chemical analysis, X-ray diffraction (XRD) and petrographic analysis can achieve this.The chemistry of groundwater is dependent on the water velocity. Water at deposition and post-diagenesis dissolution of minerals by hydrolysis and oxidation will result in equilibria of the dissolved phase with the solid phase. Post-depositional fractures caused by either tectonic activity or weathering alter the rate of weathering and thereby the geochemistry. Slow water flow in microfractures results in water in equilibrium with the rock minerals. Faster flow in larger fractures results in water being in disequilibria with rock minerals.Fractures can alter groundwater chemistry by two pathways: changing groundwater velocity, which changes the rate of hydrolysis or oxidation mixing water from different geological strata.Both pathways cause subtle changes in the water chemistry.It is however, the dissolved phase chemical data, which can be observed over time at individual locations and/or at a point in time along a flow path, which allows the hydrogeologist to ælook up-gradientÆ and locate the zone of leakage. Hence, influences on rock/groundwater chemistry, from anthropogenic sources to natural mixing of waters, can be assessed via appropriate interpretation of geochemistry, hydrogeochemistry and flow data.This paper will use the example of the geochemical and hydrogeological characterisation of aquifers within the Hawkesbury and Bulgo Sandstone of the Southern Coalfields to the south of Sydney in New South Wales to demonstrate this approach.CITATION:Stuckey, M and Mulvey, P, 2013. Looking for fractures - integrating geochemistry with hydrogeology to find inter-aquifer leakage above dewatered or collapsed coal seams, in Proceedings Water in Mining 2013, pp 99-108 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013