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By S J. Woods

As a part of Solid Energy's progressive rehabilitation of the Stockton Mine, it was determined that significant rehabilitation of the existing Mt Frederick Sidecast would be required to ensure the long-term stability of the sidecast. The goal of this rehabilitation is to reshape the existing stockpile into a more stable slope configuration, and the construction of a comprehensive stormwater collection and discharge system. The reconfigured slopes will facilitate the final revegetation of the exposed surfaces and the management of surface and groundwater discharges from the area. This paper briefly describes the specific details of the project and the significance of seismic conditions on the long-term stability of the reconfigured stockpile.

Jan 1, 2003

Sampling is an integral part of gold bullion analysis. Gold mining industries sell millions of dollars worth of gold on the basis of analyses. Biased sampling can cause a serious loss in terms of monetary value to a mining company; hence accurate sampling is of great importance. The sampling procedures for gold bullion will be described. Emphasis is given to the most reliable method of obtaining a representative sample from a gold bar. The problems associated with sample preparation will also be discussed.The sampling procedure at the Kalgoorlie Metallurgical Laboratory will be evaluated in the light of comparative results from the Australian Gold Refineries (Perth, Kalgoorlie). The most common sampling practices adopted by different gold mining companies in the Goldfields and Australian Gold Refineries, Western Australia will also be presented.

Jan 1, 1976

By J P. R de Villiers

The Vanderbijl Park sinter plant in South Africa was investigated to determine the reason for the production of very fine sinter not acceptable as feedstock for the blast furnace. A procedure was designed to generate representative samples and to prepare the samples for chemical and mineralogical analyses. Results from a mineral analyser showed that the samples are extremely heterogeneous and therefore the sampling and sample preparation methods had to be tested in order to produce representative samples. The high production capacity at the sinter plant could also give rise to sampling errors. The method designed involved sampling of the conveyor belt at the sinter plant every four hours for the duration of three days. The samples were then milled and split into smaller sections appropriate for analysis. X-Ray diffraction (XRD) and X-Ray fluorescence (XRF) analyses were conducted on the samples. The results showed a standard deviation of less then one per cent, which indicates that the samples were representative and that the method used was therefore adequate. Systematic differences in the phase proportions between normal and fine sinter samples were detected, with the fine sinter containing more haematite than the normal sinter. The sampling method employed gives added confidence that the differences are real.

Jan 1, 2008

By Wilson O. A, White R. W G

The Mount Morgan mine occupies a unique place in the mining history of Australia and although not as glamorous during the second phase of its existence, it made a significant contribution to the technical and financial history of the nation throughout its life. The stories of the intrigue surrounding its discovery and early operation, the enormous return received by its original investors in its first five years as a public company, its influence on the local, national and international scene to its final closure have been documented in many publications, the most recent and authoritative being by John Kerr (1982). Institute publications as far back as 1911 have documented details of the mining, metallurgical and engineering practices of the two companies which worked the 100 or so acres which were alleged to be `the richest single gold mine in the world'. Within the Institute records appear the names of Presidents, Institute Medal recipients and others connected with Mount Morgan who have played an important part in the Institute history.

Jan 1, 1993

By Sanders GJ

Coals from the Southern Coalfield of New South Wales treated in the Port Kembla coal preparation plants of Australian Iron and Steel Pty Ltd differ substantially in their characteristics. Knowledge of, performance not only enables comparison and promotes better control, but also provides the means for predicting results. Evaluation of performance of cleaning equipment has been made in terms of probable error (Ep.) Results for Baum jigs, a Chance cone, heavy medium cyclones and water washing cyclones are examined. The efficiency factors derived from the probable error are applied to the float and sink analysis, mathematically simulating operating conditions. This method is applied to the Balgownie seam. The Balgownie seam lies between the Bulli and Wongawilli seams in the Coal measures of the South Coast and mining on a large scale began recently in the Bulli area. It is known locally as the Four Foot seam and exhibits er difficult washability characteristics, due to a comparatively high middlings content. These properties and the tively high inherent ash make careful selection of cleaning equipment essential for optimum recovery. The prediction technique is used to determine the possible results when this coal is cleaned in the Port Kembla plants. Predicted values are compared with results from full scale trial washings demonstrating the validity and accuracy of the technique. Applications of result forecasting are listed.

Jan 1, 1970

Risk Management has been applied relatively slowly in the mining industry. Except for the risk concept application in financial considerations, the application of Risk Management in safety management has been far from satisfactory. When applied it was treated in a global occupational safety and health sense. Regardless of how much the mining industry has progressed over the years it is still, in many respects, `state-of-the-art' business. The safety aspects of mining are well known and yet little understood by the public. Regardless of what has been achieved so far and how much effort has been put into it, mining is regarded as an unsafe and somehow rude business. Safety records of the mining industry vary from State-to-State. Latest mining related disasters in PNG and Queensland and some other fatal accidents support this public perception. They purport a need for change in managing safety in the mining industry. The latest mining fatalities have raised the issue: What must be done to improve safety standards? Duty of care, risk management and system engineering concepts can provide some answers. Risk Management principles which have been advocated for some time provide many answers and explanations and can make safety management more constructive and workable. What has been missing so far is that this concept has neither been applied nor has been modified for its practical application and purpose on a larger scale. A risk management approach to the management of safety and health in the mining industry is addressed, herein. This approach does not attempt to provide the solution. It does, however, provide a basic understanding of what Risk and Risk Management are all about. Rational management of risk is addressed in the life cycle and system contexts. A system of continuous improvement is applied. There is always a chain of events, outcome, exposure, consequence(s), and consequence(s) value(s). It means that development of an event takes place in time and space. Dynamic circumstances have been created in or within the system. It is a decision-making process designed to provide a methodology which is directed not toward a mathematical model but toward easy use and application in dynamic working environment, by decision-makers who can be anybody from either a risk taker or a risk creator. The emphasis is placed not only on arriving at the best practical, possible and fair decision but also on structured and systematic acquisition of knowledge about the system, its hazards and associated risks, hence increasing the decision maker's ability to manage the decision-making process related to the management of risk.

Jan 1, 1995

The Australian mining industry has suffered from a decline in its public image during the past decade. This has occurred partly as a result of increased questioning of accepted social and economic values since the mid-1960s and the greater restrictions placed on industry since then, and partly ò from the industry's inability to effectively answer its critics. Public opinion surveys have shown the depth of the decline in the industry's community acceptability and highlighted those issues which people regard as disadvantages of mining. The industry's poor public image has contributed to the difficulties of attracting young people to take up professional careers in mining. All those involved in the industry have a responsibility to assist in activities designed to improve the industry community Acceptability.

Jan 1, 1981

By D La Rosa, W Valery, A Jankovic, S Ese

Metso Minerals Process Technology Asia-Pacific (MMPT-AP) has been working with many mining companies worldwide performing æMine to MillÆ or Process Integration and Optimisation (PIO) studies. MMPT-AP has developed a proven methodology to improve the efficiency of the mine-mill interface and gain maximum benefit. The PIO methodology involves rock characterisation, mathematical modelling and simulation to generate a list of operational and control changes for both the mine and concentrator. Following the methodology, the list of recommendations is developed relatively easily; the more challenging part depends on the company. Success of a PIO project relies on the ability of an organisation to implement change û both operationally and culturally: the human element. When a PIO project is started, there is initial interest and commitment from the company. But how can this be maintained? How does an operation know if the benefit continues? MMPT-AP is now developing long-term relationships with clients to ensure that the increased production and improved efficiency continues. Direct and indirect measurements are used to determine the key factors involved and to understand the cause/effect relationships. Simulation tools also can be used to compare current with recommended practices û so when material properties vary over time, the benefits can still be quantified. PIO is about empowerment: by measuring and understanding what parameters affect concentrator performance, the site personnel now have the knowledge to make a difference. Rather than simply reporting variable or poor concentrator performance, operations can predict when production will be affected and put controls in place to prevent it from happening. This requires support and commitment from the company or æbuy inÆ. Ensuring this buy in continues is the challenge facing every company involved in PIO work û but the benefits are well worth it. This paper will review MMPT-APÆs experiences in implementing PIO projects in the long term: from both the consulting and operational viewpoints. MMPT-APÆs involvement with a number of companies will be discussed as examples of what works and what does not.

Jan 1, 2007

By E du Plessis, J Kapusta, J L. Mauk

The world-class Bulyanhulu gold deposit (375 t Au) is in the Sukumaland greenstone belt, Northwestern Tanzania. The main mineralised quartz vein structure, termed Reef one, occurs at the contact of felsic metavolcanic rocks on the hanging wall and mafic metavolcanic rocks on the footwall. Reef one is dominated by massive quartz together with pyrite, pyrrhotite and minor chalcopyrite. Alteration in the footwall basalt is characterised by extensive chloritisation, calcification and silicification, which is strongest near the vein. Sericitisation also locally occurs adjacent to the vein. Metamorphic hornblende and plagioclase (albite) increase in abundance at a distance of 120 m from the vein and reflect the gradation into less altered rocks. The increasing abundance of chlorite, calcite, quartz and local sericite near Reef one, coupled by replacement textures suggests that most of these footwall minerals are the product of hydrothermal alteration, rather than regional metamorphism. Geochemical data shows slight enrichment in Ca, Fe and As towards the vein, whereas Zn in several drill holes becomes enriched away from Reef one. The Bulyanhulu gold deposit is a quartz-pyrite-chalcopyrite shear controlled vein with an adjacent extensive chlorite-quartz-calcite hydrothermal alteration zone (and a limited local sericite alteration zone) that passes to a hornblende-albite metamorphic assemblage further into the footwall.

Jan 1, 2002

Interest in mineral sand mining in the south west corner of Western Australia began in the late 1940's and significant production commenced in 1956. Early land use conflicts arose because of conservation implications (Ludlow tuart forest), expanded to include post-mining rehabilitation requirements (the Wonnerup mine near Busselton) and today include some agricultural/mining disputes. These latter conflicts are largely caused by the need for mining companies to secure longer-term reserves. To date, deposits containing mineral valued at A$440 million have been sterilized and are unlikely to become available in the future. There is additional pressure being placed on presently available reserves and a pessimistic picture could be drawn, whereby the southwest mineral sands industry ceases to exist by the year 2010. However, sensible land use planning, the support of policticians and the community, and responsible attitudes towards compensation and rehabilitation could, in combination, see the industry maintain significant mineral output until the middle of the 21st century. Examples of deposits sterilized by adverse land use will be given.

Jan 1, 1986

By Moorrees C, Koh P. T L, Tsambourakis G

Examination of Ihe calcination and carbonic acid leaching behaviour of a number of Australian magnesites shows that there are substantial differences between the massively crystalline and the cryptocrystalline forms of magnesites. Crude magnesias formed by calcination of the massive variety of magnesite have considerably smaller surface area and show lower rates of reaction with carbonic acid when compared With those derived from cryptocrystalline magnesites. In order lO producc a rcactivc magncsia from massive magnesite, the calcination conditions must be carefully controlled over a narrow temperature range (eg 680-720°C). For the cryptocrystalline calcines, the temperature of formation has little effect on reactivity.The results confirm the general applicability of the calcination/carbonic acid leach process for producing magnesia from magnesitc. If a mixed crystalline/cryplocrystalline feed is to be processed, then processing conditions must be optimized in terms of the behaviour of the crystalline component of the feed.

Jan 1, 1985

IT is intended herein: to make some brief comments on geophysical 'work in general and on the various methods, and then to refer to that branch which, perhaps, is of the greatest importance and interest to the metalliferous mining engineer, i.e., the variousmethods of electrical prospecting.The term geophysics was originally applied to those larger physical and geodetic studies and methods concerned with such purely scientific subjects as the investigation of the true figure of the earth and the determination of the stability relations resultingtherefrom. Applied geophysics and geophysical methods of prospecting are concerned primarily with the search for, and investigation of, useful mineral deposits concealed within the earth's crust and not readily detectable by the normal methods employed bythe mining geologist and prospector. The methods employed have been devised as a result of co-operation between mining men, geologists, and physicists, and, although steady progress has been made during the past 20 years or so, it is within the last four orfive years that the importance of these methods has been acknowledged by the mining world in general. Although many of these methods are still in, or have barely emerged from, the experimental stages, a steadily increasing list of important discoveries is attributable to their employment-more particularly in Europe and America than elsewhere. The various methods have each their own limitations regarding the class of work they can undertake, and no one method is capable of general application. The greatest care should be exercised in selecting the method, or methods, to be employed in any particular area, the...

Jan 1, 1928

By Willey GJ

A brief test program was undertaken to assess the viability of air-sparged hydrocyclone beneficiation at the Cadjebut concentrator. Three different process streams were processed (lead rougher feed, lead scavenger tail and `mine water' solids) in a small scale ASH unit (one litre volume, feed rate 1000 to 1800 kg solids/hour). Analysis of the concentrates indicated that ASH based flotation was successful, selective and capable of achieving improvements to the overall metallurgical performance of the concentrator. The flow regime inside the device accentuates the selective flotation of the finest particle size ranges generally not recovered to any significant extent in conventional mechanical flotation devices. The testwork proved that the ASH is a viable alternative option for increasing the flotation capacity of the lead beneficiation stage of the Concentrator.

Jan 1, 1993

By G Kuntz, V Wall, B New

The prime aim of the Campbell Mine project was to develop a 3D geological model for the Campbell-Red Lake system to contribute to an exploration model for the region. The base data is composed of over 60 years of geological data covering an area of 16 by 8 km, and from surface down to 1830 m depth. This paper concentrates on the methods used in the GeoSpace system for the processing, integration, display and interpretation of such a large and diverse data set. A block model was developed that recorded the relative frequency of each geological feature within each block. The data input for the block models were based on recoding of the Campbell Mine drilling and channel sample databases into lithological, alteration and structural subsets. The value for each geological characteristic inserted into each block is calculated from all available data that falls within the block. Relative and absolute comparisons of the individual variables provide a targeted outcome from which the blocks are coloured for visual inspection. Different combinations of variable comparisons can be evaluated so that required features are highlighted for interpretation. Blocks are displayed to illuminate the ædominantÆ rock type, according to a formula that may be varied interactively to display the features required by the geologist. This flexibility allows rapid remodelling of lithological distributions, commonly highlighting minor lithological packages not readily visualised in, and interpreted from, drillhole traces alone. The 3D geological model was built from the drillhole datasets and old mine plans utilising standard 3D mining, GIS and database software, with several iterations of plan and sectional interpretation. Near surface bedrock geological interpretations were further constrained by low level aeromagnetic data. The Geospace approach employs an innovative technique for visualisation of the distribution of lithological packages and alteration via block modelling. The method utilises the block model format of data handling as it is considered to be more visible than drilling, flexible enough to incorporate a wide range of data sources, and allows for spatial proximity relationships to be investigated. The method is a simple form of processing large data sets so that results are clearly visible. The calculation is much more rapid than estimation procedures, and does not have any requirement for geostatistical interpretation which is also time consuming. Geospace is not unique to any mine environment software and it is expected to be able to be performed in any system. The proper portrayal of the internal structure of the mineralised body will provide practical input to exploration and mining principally in the areas of resource estimation, exploration vectoring and ore/waste characterisation and may be incorporated with other data to include mine support and mine scheduling.

Jan 1, 2003

The title of my address today is "Oil and Gas Valuations - A Simplistic View of Some Critical Issues". Alternatively I could have called this address "Pitfalls for investors' and corporates in accessing Independent Experts Reports" 'as in this brief 12 minute talk I will briefly comment on some common misconceptions with regard to the valuation of exploration areas and production interests, and comment on how the draft release guidelines address these issues.

Jan 1, 1989

Industry has a very special request to make. Environmental issues must not be allowed to become a factor of competition so that nations or individual industries can gain economic advantages for themselves by encroaching unduly upon the environment. An international harmonisation of the demands imposed on specific industries and industrial plants where discharges are concerned is therefore essential. The same applies to any to any action contemplated against noxious products. An important step towards that goal is no doubt represented by the United Nations Conference on the Environment scheduled for 1972. Conclusions: Australia must recognise its responsibilities in an inter- national movement to control pollution. It must react on a national scale to a problem which is threatening our whole national environment. To gather, collate and coordinate the information needed to ensure policies which strike a balance between conservation and development, we must look towards the Commonwealth to coordinate the activities of its own instrumentalities and those State and independent bodies working in the area. Financial aid must be provided to stimulate research and later to ensure that environmental protection policies are observed. These policies will be founded on social economic theories which will be both practical and sound, The United Nations conference on the Environment is scheduled for 1972 and in this is the opportunity for international cooperation. Cooperation in the field of controlling legislation and the collection of much needed data. There is an imperative need to assemble facts for world use - an international know-how bank which acquires the most sophisticated technology of process design and waste purification. Arising out of this Conference, is it too much to expect that there could be established an international authority for environmental control, whose activities are governed on a multi-national basis? Such an organisation would have as its primary concern the collection and classification of official regulations, as well as the sheer collation of data to permit economic evaluation of the costs of conservation of the environment. There is an international scope with different factors involved, including industrial technology: in other words, the concrete measures taken against industrial pollutants ought to be more or less identical for similar industries irrespectives of the countries in which they operate. The assembling of an international common foundation of knowledge is imperative so as to acquire the most sophisticated technology of process design and waste purification available for all who are interested.

Jan 1, 1971

It was once considered sufficient to revegetate old mine sites using grass or trees. At the commencement of the Stawell JV (SJV) operation in 1981, management determined that pre-existing vegetation would be replaced. This policy was somewhat 'ahead of its time'. The cost of rehabilitation at SJV averages $8000 per hectare. Rehabilitation of this calibre requires a practical understanding of local ecosystems.

Jan 1, 1992

By P Allum

This paper presents a case study to reduce the operational cost on the secondary ball mill circuit in the Lead/Zinc Concentrator at Mount Isa Mines. The circuit includes two five-metre diameter ball mills each closed with a cluster of ten 15-inch cyclones. The operating cost for both ball mills is about six million Australian dollars per annum.The concentrator achieves 75 per cent of the plant design capacity with one ball mill operating, but will have to use two ball mills when 100 per cent plant capacity is required. The optimisation study on the circuit identified a new flowsheet that enabled the concentrator to reach 100 per cent of the capacity by using one of the two secondary ball mills. The success of the project utilised the existing equipment rationally and saved the operational cost for one ball mill at full concentrator capacity. A further simplified secondary circuit is proposed using the IsaMill for the secondary grinding duty. Performance of the IsaMill circuit and the potential cost savings are predicted.

Jan 1, 2002

Mineral exploration and development can have a significant impact on the environment and local communities, in some circumstances extending well beyond the mine site. Poor environmental performance and consequent social impacts by some companies have affected the reputation of the whole industry to the extent that the principal public concern about mining is its impact on the environment. This is consistent with public attitudes about other major natural resource sectors such as forestry and commercial fishing. Traditionally the community has relied on governments to set the benchmark for acceptable environmental and social performance through establishing and revising regulations governing the mining industry. This however assumes that regulations keep pace with community expectations. It also does not take into account those circumstances where governments can have conflicting roles as both watchdog and project partner. Government regulations and industry self-regulation are not in of themselves sufficient for the minerals sector to demonstrate that it has adequately addressed environmental and social issues associated with the sector. For the minerals sector to improve its reputation it must first improve its environmental and social performance. To do this requires the sector to operate to acceptable standards of environmental and social performance and for the sector to be able to credibly communicate this to its stakeholders such as investors, non-government organisations (NGOs), customers, staff, regulators and local communities. Independent third party certification of environmental and social performance (æcertificationÆ), already operational in forest and fisheries management, is proposed as a mechanism to enable the minerals sector to achieve this. World Wide Fund for Nature (WWF) and industry partners will be collaborating in a project to ascertain the applicability of æcertificationÆ to the minerals sector. A number of economic, social and environmental benefits are identified that could accrue should mining companies be able to differentiate themselves on the basis of environmental and social performance, an attribute evident in æcertificationÆ schemes. External audiences are seeking increasing levels of information and data on environmental and social performance of mining companies, be it local communities, investors, financial institutions or NGOs. Environmental and social reporting should be a key communications device that stakeholders can rely on as a reliable, credible source of information on environmental and social performance. WWFÆs contribution to the debate about environmental and social reporting has been to develop a process to assess the quality of environmental and social reports against reporting ingredients which WWF believe are important if a report is to be an accurate reflection of the reporting entitiesÆ environmental and social performance.

Jan 1, 2002

By Baker EM

The Kidston orebody is a kilometre diameter breccia pipe of Permo-Carboniferous age' assoc- iated with rhyolitic dykes and hosted by Proterozoic granodiorite and metamorphic rocks. Mineralization and alteration are associated spatially and temporally with brecciation and rhyolite intrusion. Three stages of alteration have been recognized: pre-brecciation, and early and late stage post-brecciation. Gold is known to be particularly associated with late stage post-brecciation cavity infill and sheeted veins. Fluid inclusion and stable isotope results show the importance of moderate-high temperat- ure, saline, magmatic fluids in the early stage mineralization and in the brecciation of the pipe. Later periods of alteration, accompanied by gold deposition, are associated with fluids only slightly depleted in 180 relative to mag- matic waters, unlike the strongly 180-depleted meteoric water typically found in hydrothermal Permian and Carboniferous deposits of eastern Australia. The 5180 values and low salinities in fluid inclusions suggest the fluid may have formed from vapour condensation from a magmatic fluid. Fluid inclusion data and alteration assemblages define the prevailing chemical conditions. Gold transport under these, conditions would have been primarily as a bisulfide complex.

Jan 1, 1987