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By A Creighton, C McKenzie

Blasting is a critical task in the development of an open pit. The formation of stable slopes is also essential to the safe and economic extraction of ore. The objectives of a mine blasting department are often considered to be in direct conflict with those of the geotechnical department. This should not be the case. Personnel in the various mining departments need to understand that their goals are the same û to optimise safety and cost-effectiveness of the operation. Blasting has the potential to damage rock that is to remain in situ by generating either excess vibration, and/or pressure. These damage mechanisms are described and guidelines with respect to blast design to minimise the potential for damage are given. A rock mass could be expected to be subjected to varying degrees of damage by blasting, including both intensity of damage and also the extent of damage. These issues have potential to impact significantly on geotechnical design considerations. It is therefore important for the practitioner to define what constitutes damage. In the context of mining, it is recognised that there is a need to balance the requirements for efficient excavation with those of forming stable and cost-effective pit walls. It is therefore important to have a set of key performance indicators (KPIs) against which the performance can be bench marked. These would include cost and time, both of which may be influenced by very diverse factors such as drilling, explosives and their performance, fragmentation, excavator and haul truck performance, requirements for batter clean-up and safe working practices. KPIs are identified and discussed in this paper.

Jan 1, 2003

By P Trotta

The majority of water to the Olympic Dam mine and the nearby townships of Roxby Downs and Andamooka is supplied from the Great Artesian Basin (GAB). There are no permanent local water sources available to Olympic Dam. The use of water from the Great Artesian Basin by Olympic Dam receives considerable attention by BHP Billiton and is extensively regulated by the Government of South Australia. Olympic Dam has robust business management systems in place to ensure the sustainable use of water from the GAB including ISO9001 and ISO14001 systems to deliver the targeted outcomes and obligations of the Olympic Dam Environmental Management and Monitoring Program. The management systems ensure that Olympic Dam retains accountability for its water demand from the GAB over the life of the mine. This accountability has delivered continuous improvement in water use efficiency driven by operating discipline, implementation of water saving projects, using water on a fit for purpose basis including substitution from non-GAB sources, and risk management to prevent and mitigate water supply disruptions to Olympic Dam and Roxby Downs. Since the establishment of Olympic Dam, BHP Billiton has funded a reduction in GAB water flow from bores, previously going to waste, that is greater than the annual average flow used by Olympic Dam.

Jan 1, 2009

By Whiting AN

Major changes in the world in recent years are changing the criteria for selection of future developments. Oil prices soared during the 1970's while commodity prices including metals and minerals fell. Many new independent nations, have been created and now control the resources in areas which were once part of great colonial Empires.

Jan 1, 1983

By W P. Darcey

Jabiru Metals completed a feasibility study on the Jaguar Base Metal Project in July 2005. The study was based on conventional truck haulage via a decline. Conveyor haulage was considered but not in sufficient detail to provide a meaningful comparison. The current study investigates the cost and productivity of alternative ore transport systems for the Jaguar project. The options considered are conventional underground truck, conveyor, road train, rigid frame truck, monorail haulage and shaft hoisting. Shaft hoisting was not considered in detail due to the high capital outlay for such a relatively short mine life of less than six years. This study goes beyond the common approach of evaluating haulage systems in isolation; it includes development costs, timing of ore production and costs associated with mine services as well as administration and milling costs. The results of this study indicate that the best haulage option for the Jaguar project is conventional truck using the Hitachi AH400 trucks. The net present value (NPV) for this option is A$8.13 million higher than the next best option namely the Kiruna E635 electric truck. The conveyor option has the lowest operating cost per tonne of ore but the longer development time negatively impacts on its NPV. The monorail option is considered impractical due to the number and length of trains required to achieve production targets.

Mar 21, 2011

By N Power, A D. Costar

There has been significant growth in mining and energy exploration in South Australia, which has identified new major potential opportunities. This sector generates significant economic value to the state and their support remains a priority for the state government. The delivery of this economic and associated community value to the state is dependent on the mining and energy sector being able to access reliable water supplies.The vast majority of priority areas for the mining and energy sectors are located in areas that have traditionally been of low priority from a water-use perspective and hence, data and knowledge levels are generally low.Recent studies have identified a potential increase in demand for water in the mining and energy sector for potential developments from approximately 40 GL to over 170 GL over the next ten years. The studies found that water and water infrastructure is the second highest proportion of planned infrastructure capital investment by resource companies. The South Australian GovernmentÆs Plan for Accelerating Exploration (PACE) initiative (PACE 2020), also identifies addressing the issues of location, use and management of South AustraliaÆs water resources as a key priority for the growth of the mining and energy sector.The Department of Environment, Water and Natural Resources (DEWNR) has developed the facilitating long-term outback water solution (FLOWS) initiative. DEWNR is currently undertaking a suite of programs to provide groundwater information at the regional scale to better target water supply options for mining and energy developments and community water supplies.The Goyder Institute for Water Research has leveraged significant research investment of $3 M to develop methodologies to interpret airborne geophysics to map groundwater sources.The FLOWS Initiative will provide key content for the PACE Water Program and will also assist in the development of water supplies for remote far north communities by identifying alternate groundwater sources to improve water supply security.This paper will discuss how developing an appropriate science and knowledge base will encourage and secure development where appropriate, enable prudent decision-making and policies regarding water allocation, accounting and licensing, whilst ensuring the protection of environmental assets.CITATION:Power, N and Costar, A D, 2013. Finding long-term outback water solutions, in Proceedings Water in Mining 2013 , pp 191-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Cornell J. B

Scaling in Bayer Refineries is a natural consequence of the super-saturated liquors used in the process. The caustic liquor is supersaturated not only with alumina but also silica and calcia at various stages of the process. The basic scaling mechanisms are reviewed and examples of the two basic types, growth and settled scales, are given. Examples include gibbsite scales formed in the precipitators and silica scales formed in heat exchangers. The main factors affecting the rate of growth of growth scales are temperature and supersaturation and are highlighted using a silica scale example. For growth scales chemical cleaning rates can readily be predicted from kinetics and an example for a gibbsite scale is given. For settled scales the growth rate cannot be predicted and the hydrodynamics within the system have most effect. There is no simple method to predict the potential for chemical cleaning of settled scales; some of the relevant issues are discussed, in particular methods to identify the cementing phase in the scale. An example of design considerations for a scaling system, transport of slaked lime, is Given.

Jan 1, 1996

By Boyd G. L

Stress measurement is at the core of most stability design analyses. It is demonstrated that contrary to accepted practice, it is the field measurement, and not the calculated prediction, of stress that requires most examination and review. Since it is not really possible to quantify rockmass properties, the stiffness values used in reduction of stress measurements and in subsequent design analyses (either empirical or numerical modelling) must consider an appropriate range of values.

Jan 1, 1995

By Van Hoorn PD

For the development of BHP's Gregory open cut coal mine in Central Queensland a mini computer was successfully used to assist staff in the evaluation of the deposit and the planning of the mine. The Gregory deposit is essentially a single mineable seam deposit, however the systems developed may be applied to other coal deposits including multi seam occurences. The first phase of the Gregory computer evaluation and planning project involved the establishment of a borehole data base for the storage, retrieval and analysis of both strata and quality data. During the second phase a numeric block model of the coal deposit was created. Using this model reserve calculations were carried out by specifying the area with the aid of a digitizing tablet. The third phase involved the develop- ment of systems to simulate the dragline stripping operations including the rehandle percentage calculation, a dragline production schedule showing coal quantity and quality exposed, and a combined multi dragline operation schedule that can produce figures and graphs for up to 20 variables. A derivative of the operating plan was a programme that gave productioh cost estimates

Jan 1, 1978

By Miller RJ, Eager DT, Lama RD

For safe and efficient mining operations, it is essential that environment and equipment status be monitored. A system that gives quick access to status at any given time, and also permits quick analysis of their history, is required. Such a computer based monitoring system has been installed at West Cliff Colliery.The system is based on 2 super mini computers. Three major sub-systems monitor conditions in the longwall operations, environmental conditions in the intake and return roadways, status of the underground and surface installations, and mining and transport equipment.

Jan 1, 1985

Many volcanoes in western Melanesia have tectonic settings and rock compositions that do not conform to conventional models of arc- trench systems. Part of the reason for this may be that in an environment of rapid tectonic change mantle source regions bear the imprint of former subduction even though subduction has now ceased. Results bearing on this concept and on other important aspects of Plelit nesian v ican ism and tectonics, were obtained in 1982-1986 from >e,:eral marine - geoscience studies in the re,,ii n

Jan 1, 1987

By Keele R. A

The Cambrian structure in the Mt Read Volcanics was produced by four deformational events: obduction of forearc-derived mafic/ultramalic complexes in the early Middle Cambrian, a middle Middle Cambrian extensional phase related to the post-collisional Mt Read volcanism and VHMS mineralisation, Middle Cambrian E-W folding, and Late Cambrian N-S folding and basin inversion. The major phase of VHMS mineralisation in western Tasmania is restricted to the very brief period of extensional tectonics within the middle Middle Cambrian. Within this period a N-S graben was produced with a complex series of transfer zones, largely striking E-W. Most VHMS mineralisation is restricted to the top of massive volcanic successions, with several mines close to Cambrian transfer structures. Many of the transfer structures continued to be active until the Devonian. The later compressional Cambrian events are not significant in localising orc formation. Within the Rosebery mine a complex pattern of minor Cambrian normal faults has a second order control on the distribution of the mineralisation.

Jan 1, 1997

By E Mare

Recent highly publicised incidences of disastrous containment failures, none more pertinent than the 2019 iron ore tailings dam failure in Brumadinho, have focused the world’s attention squarely on the often-challenging subject of tailings storage. Unwanted ultrafines, that are deemed to be unworthy of further treatment or not to have further saleable value, are therefore a significant issue for mine owners looking to reduce risks and perceptions associated with long-term storage of tailings. In this context, there are strong drivers to identify safer approaches to ultrafine tailings management, especially if it can also lead to increased revenue, together with better water stewardship and environmental outcomes. The better management of tailings needs to be considered from both containment challenge and processing opportunity perspectives. This paper focuses on the latter, reviewing from a technical and economic perspective, the feasibility of more extensive processing and/or reprocessing of specifically iron ore tailings, in a bid to reduce the overall volume for management in long-term storage. Herein the opportunity lies in recovery processing, as much as enhanced thickening and/or mechanical dewatering, and therefore the paper discusses both issues as equally important sides of the same coin. Recent interest in iron ore ultrafines processing and reprocessing studies suggests that the enhanced processing of iron ore tailings offers multiple perceived advantages. Apart from a potential reduction in tailings volume, associated with safer containment, lower environmental impact and improved water management, the prospect of increased revenue from additional Fe recovery presents supplementary motivation for iron ore players to embrace this approach, as further elaborated in this paper.

Nov 8, 2021

By Zhou Y, Karmis M, Haycocks C

Hazard analysis utilizes interaction mecha- nisms in combination with geologic, structural and mining conditions to delineate areas of potential damage in seams subject to interaction. Using characterizations of conditions peculiar to multi- seam mining, such as innerburden thickness, geol- ogy and structures, initial interaction contour maps can be constructed. Geologic hazard analysis is then carried out on roof, pillar and floor condi- tions in the affected seam using lower seam rock properties and layout geometries in the overlying seam. Either safety factors or damage ratings can then be developed representing degree of hazard in the lower seam. The final hazard map shows both the aerial extent and magnitude of potential dam- age from interaction.

Jan 1, 1992

By Cocks T

The 15-year long debate between the industry, Government and Aboriginal people about the rights and wrongs of Land Rights, the right of Aboriginal people to control development on their land and the relationship between the parties, has been long and often bitter. It has so far been a war of words and often the truth has been the first casualty. This paper looks at the debate and presents the perspective of Aboriginal people, as well as looking at how the industry and Aboriginal people can work together for everyone's benefit. It addresses such matters as: ò why Aboriginal people believe they have the right to control development on their land; ò the perception that Aboriginal people are anti-development; ò the perception that Aboriginal land is 'locked-up'; and ò how companies can negotiate with Aboriginal people.

Jan 1, 1994

By M Wortley, J McKay, D La Rosa, O Guyo

It has been a generally held concept that crushing operations were, by their nature, too simple to benefit from the implementation of advanced process control. The commissioning of an OCS¬ expert control system and image-based oversize detection system, VisioRock, at the Pilbara Iron Tom Price facility are dispelling these notions. A constraint-based OCS¬ expert control system has been designed and commissioned on the high-grade crushing and screening plant along with a vision-based oversize detection system functioning on six product conveyor belts. To date, the expert control has demonstrated the ability to increase production by maximising dynamic constraint utilisation. Dynamic constraint utilisation is a concept developed by Rio Tinto Technical Services for effectively evaluating constraint-based control logic performance. The VisioRock system has been installed and configured and has been operating for a period of several months. Currently, Tom Price and Metso personnel are working to define correct oversize detection thresholds. Details of the plant implementation are discussed.

Jan 1, 2005

By Greaves J. N

The U.S. Department of Interior, Bureau of Mines, is investigating the treatment of refractory gold ores. Chlorination in the treatment of refractory gold ores is applicable in many low-grade gold operations. When usable, this treatment provides an economic means of consuming sulfides and deactivating disseminated organic carbon. Chlorination, however, is a pretreatment technique that requires the neutralization of the chlorine prior to leaching the ore with cyanide. Research by the Bureau has extended the present chlorination technology to allow for the recovery of gold without the use of cyanide and allow treatment of some ores presently deemed untreatable by gold operators using cyanidation or chlorination/cyanidation techniques. Chlorination without carbon of two carbonaceous ores extracted between 1 and 20 pct of the gold; however, carbon-in-chlorine (CICL) treatments resulted in about 90-pct recovery with a reduction in carbon loading. A statistical design campaign for stripping metallic gold from the carbon loaded in a chlorine environment demonstrated elutions exceeding 90 pct.

Jan 1, 1991

The celebrations which took place in 1986 to mark South Australia's Jubilee 150 served to focus attention on all aspects of the State's heritage. Until that time the sites and relics of South Aus- tralia's early mines had been generally neglected. Marked by the ruins of enginehouses and littered with the remains of the massive technology of the Industrial Revolution, these sites have now been recognised as containing the threads of a fascinat- ing story. In the early days of settlement the economy of the Colony was based on land and farming. Droughts caused periods of economic depression which were alleviated by chance discoveries of gold, lead, silver, and copper ore. Some of the mines which were opened on the copper deposits were the largest in the world at that time and their names well-known throughout mining circles. Working by hand with primitive equipment, the early miners excavated vast networks of shafts and stopes often extending to great depths: at Moonta- Wallaroo Mines for example workings extended to 860 m below ground. Because of the presence of underground water, mining to these depths would not have been possible without the Cornish pumping engine. Operated by steam power these massive engines and their associated equipment were transported from Cornwall by clipper and delivered to the mines by bullock cart. At this time the engines were at the peak of their devel- opment and, although expensive to import and install, they were highly reliable: the engine oper- ating Hughes pump at Moonta worked continu- ously for sixty years without a major breakdown.

Jan 1, 1987

By Marshall K. I

THE problem of satisfactorily eliminating the fumes and dust which are unavoidably produced in various metallurgical and manufacturing industries is one which has received considerable attention in the past, and has been the subject of much investigation and research. The solution of this problem was urgently desired for two reasons, the principal one being the fact that a considerable percentage of the total process losses in many industries was represented by the commercial values of the fumes and dust that escaped from the stack.The other reason is that, in some instances, the emission of the matter is regarded as objectionable. Various methods have been designed with a view to solving the problem thus presented, and the latest development that has beendesigned is the process of electrostatic precipitation. Continued investigational and developmental work with this process has already demonstrated its applicability to many industries, and new uses to which the process can be put are being opened up. Its use is already widespread, and the economic success that has attended its application in most instances would indicate that its use will become more general in the future.It has proved its ability to treat gases over wide ranges of temperature, and has successfully handled various types of fumes whose chemical characteristics differ very considerably. In many processes it has now come to be regarded as standard equipment.HISTORY OF ELECTRICAL PRECIPITATIONThe first recorded observations on the influence of an electrified insulated wire on gases containing solid particles in suspension was made as early as 1824 by Hohlfeld, in Leipzig. He found that, if he electrified a wire hung in a bottle filled with smoke, the smoke cleared rapidly, and a deposit formed on the sides and bottom of the bottle.

Jan 1, 1923

White Cliffs Opal Field is situated in the Parish of Kirk, County of YulguIgra, New South Wales, about sixty miles from Wilcannia, and the River Darling. It is near the southern edge of the cretaceous basin of the interior of Queensland, New South Wales, and South Australia. Twelve miles south-west of the field, at Tarella station, a well sunk at the homestead reached silurian slates at about 127 feet, getting no water but about three miles north-west from the originally discovered and no central portion of the field, a well was sunk by the Momba, Pastoral cmpany, to a depth of 270 feet all the way through the cretaceous beds. At 250 feet a small supply of water was struck, but so much mineralised as to be quite useless. The temperature also was so high that a man could not keep his hand in it and Mr. Hogarth, the Momba Pastoral Company's manager, informs me that so corrosive was the action of the water, that a shovel left down the well for a fortnight, at the time of sinking, was completely eaten away.The well having now fallen in, I have been unable to obtain any of the water for analysis.The western termination of this portion of the cretaceous basin is situated about twenty miles from the present opal field, at which distance the slates, with (probably) devonian sandstones and quartzites resting unconformably thereon, commence to appear. The opal bearing country, as far as at present known, follows a more or less well defined line running north and south towards the northern end of the field, and north-east and south-west towards the southern extremity.

By Tilley H. L

The 90 m deep Yallourn Open Cut brown coal mine in the Latrobe Valley, Victoria is developing into an area close to a reverse fault. A major batter stabilisation program, matched to ongoing operations, has com- menced to maximise coal recovery where the fault is within 100 m of the Open Cut. The various mine development options considered during the planning stages are outlined. These options were formulated in a back- ground of geotechnical constraints and the need to maintain continuous and reliable coal supply at a time when a new coal field would be developed. The geotechnical investigations and analysis procedures under- taken to determine stability of the batters during their excavation are presented. The geotechnical constraints on the mine design and opera- tions required to ensure safe working conditions are detailed. Current operational and batter stability conditions are considered satisfactory.

Jan 1, 1989