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By Lawrence M. J

It must be stressed that the following comments are offered only to assist mineral industry professionals in understanding the issues involved in personal liability. The information and views expressed herein are not intended to be a comprehensive guide or definitive statement of the law and they should not be regarded as a substitute for specific advice for individual situations. Readers should consult their own legal and other professional advisers before applying the content of this paper to their own particular circumstances. It is hardly news that work in the mining industry is governed by a complex regulatory and legal system which is constantly changing, but few realise just how directly they can be affected and become personally liable for any breaches. These may result in civil or criminal proceedings and personal assets are at risk. Owners, company directors, managers and now employees are at risk, together with consultants, contractors and suppliers of equipment or consumables, as well as government inspectors. They are liable for their personal decisions to act (or failure to act) in managing operations or carrying out directions, as well as for the actions of others under their control. This paper identifies the areas where such individuals in the open pit mining industry in Australia face the risk of personal liability and measures which can be used to minimise the risk or which can be used to make out a defence to legal action which could arise. There have always been a myriad of Commonwealth, State and Local Government laws and regulations with which to comply, and now international protocols are being used as a basis to impose greater obligations on all people. Once, the `corporate veil' gave some protection to the individual, but today there is negligible protection from the full force of the law. Not only are there various types of law enforcement officers, but public interest groups, shareholders, customers, suppliers, creditors etc may litigate. This paper is not intended to be an exhaustive discussion of the provisions of all the legislation or case law where individuals can be held) personally liable. These areas would include environmental, pollution and heritage law (including Aboriginal sacred sites); occupational health and safety (including workers' compensation) law; trade practices and fair trading law; contract law; corporations law (including the requirements of the Australian Stock Exchange [ASX] and Australian Securities Commission [ASC]); industrial relations law; anti-discrimination and sexual harassment law; taxation (including superannuation trustee) law; and the Common Law. The focus is on the following areas of regulation, which are outside the usual experience of those in the open pit mining industry (the Mining Acts and Regulations are specifically not dealt with here): ò Environment Law; ò Trade Practices Law; ò Occupational Health and Safety Law; and ò Corporations Law.

Jan 1, 1994

By Jaracz K

At the operation of mine winders in deep shafts considerable oscillations of winding ropes may occur due to elasticity of both wind-ing and balance ropes. The amplitudes of longitudinal oscillations may reach + lm at relatively low frequencies, ranging from 0.5 to 2 c/s. These oscillations may be dangereus for the rope and produce several hazards to the winding installation as a whole. They may cause conside-rable instant accelerations on the pulley and dangerous tensions in ro-pe wires. The excessive acceleration may cause the uncontrolled rope slip on the pulley. Several methods of limitation of these accelera-tions were developed, some of them have been already in control system: of electric drive of the winder. The most simple ones are: a/ limita-tion of the rate of change of acceleration and retardation of the win-der /so called "jerk"/ and b/ the proper selection of regulators of the winder control system to get the optimal control. The trouble in solv-ing the problem of rope oscillations is that the dynamic system of the winder is a nonstationaryone owing to changing distance of conveyance from the pulley. Besides, the system is described by the equations with distributed parameters. The brief discussion of the theory and its practical aspects are enclosed as well.

Jan 1, 1985

By Ghiani M, Currelli L, Fuganti A

the results of an experimental study aimed at beneficiating a complex ore containing bastnaesite and other rare-earth minerals, with associated barite and fluospar are illustrated. Owing to its minero-petrographic, physico-mechanical and structural characteristics, the crude ore is not amenable to classic concentration methods, such as flotation, magnetic and gravity separation. Therefore the technical feasibility of selective disintegration followed by size classification has been studied, whereby bastnaesite and the other rare-earth minerals can be concentrated into the finest size fractions. Leaching and subsequent extraction of rare-earth metals by liquid-liquid separation represents the final stage of beneficiation.

Jan 1, 1993

By Miller D. R

The mineral exploration and extraction industries have gained major cost and efficiency benefits from the use of computers. However these industries are now at a cross-roads with two seemingly disparate developments - that of an increasing number of complex geoscience databases and, at the same time, the merging of all known data for the particular regions at minimal cost. These two developments can be managed by the development and of an industry accepted geoscience data model and dictionary. This will provide a common basis of understanding for geoscience data through a common language and a common structure for geoscience information. Integration of specialist systems and databases can then proceed efficiently. The development of a data model is going ahead with consensus from the mining industry. This is a joint government and industry funded project and managed through the Australian Mineral Industries Research Association, AMIRA. AMIRA is a well known research broker to the Australian mining industry obtaining sponsorship for projects both from private and government groups. The AMIRA project, P431, called the Geoscience Data Model, is to be the Australian standard data model for geoscience disciplines. The requirement for a standard geoscience data model has been recognised in Australia for some time. In October 1991, the Australian Government Geoscience Database Policy Advisory Committee (GGDPAC) established a Geoscience Data Standards Working Group which drafted a comprehensive list of data categories of the geoscience area. An AMIRA project called AMDEX was established to develop a transfer standard for the mining industry data at about the same time as this committee was in operation. The first AMDEX sponsors meeting was held in May 1991. It was proposed to use the US Spatial Data Transfer Standard (SDTS) as the basis to transfer mining data in AMDEX. A limited data model of mining data to be transferred was developed for the AMDEX standard under SDTS. The Australian Geological Survey Organisation (AGSO) saw the need to extend this and develop a complete data model for the geosciences and proposed this as a new project to AMIRA. This was strongly supported by GGDPAC which lead to sponsorship of the project from most state geological surveys. The Geoscience Data Model can be broken down into separate data models for a number of geoscience themes and sponsorship obtained so far will enable models to be developed for a comprehensive set of themes selected by the project sponsors. Further sponsorship is required to enable a more complete coverage of the geoscience area to be developed. Sponsorship for the Geoscience Data Model has been strong from the geological surveys and there was some effort by GGDPAC to promote the project in these organisations. An Australian geoscience data model is of immediate use to the geological surveys in assisting the standardising of huge quantities of geoscience data held by government agencies and it is preferable that this be an Australia-wide standard.

Jan 1, 1995

By Casale G

This paper discusses a long range mine plan development at the Santa Fe Pacific Gold Twin Creeks Mine based on the reserves of Mega pit. The key constraints of the schedule development included two types of mill ore targets (sulphide and oxide mill ore), consideration of blending of six chemical constituents (sulphide sulphur, carbonate, organic carbon, the ratio of iron/[arsenic, antimony]), and mining of acid generating and acid neutralizing waste at pre-defined proportions. Solution approaches, selected results, and project experiences are discussed.

Jan 1, 1995

An Environmental Impact Statement (EIS) for a major mining development typically has to address various aspects of surface water management, including some which generally tend to be the more contentious: the diversion of rivers and creeks from areas disturbed by mining, and their rehabilitation; the effective management of disturbed area run-off via the collection, containment and treatment of contaminated water on site in sedimentation dams; the collection, containment and treatment of mine pit water; the decommissioning of surface water storages; final void water quality; and water discharge criteria. Environmental Impact Assessment processes for proposed mining developments in Australia at the state and commonwealth level usually involve a form of Initial Advice Statement (or Notice of Intent), Terms of Reference, an EIS, and a Supplementary Report (or similar) which responds to agency and public comment on the EIS. The EIS is used by approval agencies to decide the acceptability of the Project, and to set the conditions of approval. The conditions are often in the form of a state-issued æOperational LicenceÆ or similar. With mining, the initial approval at the EIS stage is often just a pre-cursor to various other planning related approvals, including obtaining a mining lease. Afterwards, mine plans and plans of operations must be submitted to government at various stages of the mineÆs life, ostensibly to provide the detailed mine planning over periods of one û five years. Despite all this additional planning and documentation beyond the submission of the EIS, government approval agencies are increasingly not satisfied with conceptual water management designs and commitments to an outcome (such as meeting a specified water quality standard) in the EIS. Agencies are also requiring sufficient water management design information to be convinced that the outcomes are achievable. To assist proponents of major mining developments, the Queensland Government has published Technical Guidelines for water management, and Environment Australia has published a æBest Practice Environmental Management in MiningÆ booklet on water management. In addition, the Australian and New Zealand Environment and Conservation Council (ANZECC. 2000) has published Water Quality Guidelines which provide an approach to water management, and provide receiving water investigation trigger criteria. So, what are the water management issues that are likely to be the subject of comment, debate and negotiation prior to the EIS being approved? and what commitments may a mining proponent have to make in order to convince the approval agencies that sufficient investigation and design has been provided? This paper provides some answers to this question, by reference to recent major mining proposals which the author has managed through state and commonwealth Environmental Impact Assessment processes.

Jan 1, 2003

Historic mining across the Bendigo goldfield reached an average mining depth of 750 m over an area of about 16 km by 4 km, with two shafts exceeding 1400 m. Mining ceased in the mid 1900s due in part to increased dewatering and ventilation demands. Water extraction technology of the day, combined with multiple mine ownership, did not allow uninterrupted and thus economic mining activity to prosper. Today Bendigo Mining Limited (BML) is targeting gold-bearing reefs beneath the water-filled historic mine workings. To ensure mining activity can proceed without the risk of water inrush, historic workings are being dewatered by submersible pumps in historic shafts and through a series of underground drain holes intersecting old workings. Due to the high heads involved, individual drain hole development requires rigorous safety control implementation and assessment prior to drilling. Water extracted via drain holes is pumped to the surface through a series of pipe lines and rising mains in conjunction with two staged pumping stations. Both stations are equipped with high-speed centrifugal pumps, each capable of pumping 40 L/s at a static head of approximately 300 m. BML, which operates beneath and within a large city, is confronted with unusual environmental and social challenges compared to many within the mining industry. The raw mine water, which contains elevated salt levels, is piped through residential areas and must comply with strict controls to prevent impacts on the surrounding environment. The final delivery point is BMLÆs water treatment plant at the north end of the city. The water treatment plant utilises chemical pretreatment and reverse osmosis. It is able to process 7 ML of mine water per day at full production. The product is approximately 5 ML of reusable irrigation quality water, which is made available to the Bendigo community for public gardens, sporting facilities and rural irrigation. The 2 ML of brine is directed to a purpose-built evaporation pond facility located 7 km north of the water treatment facility.

Jan 1, 2008

The paper describes the development leading to the bucket wheel excavator systems now used in the Latrobe Valley and refers in particular to the new S.E.C.V. dredgers Nos. 14 and 15 which will be employed in the Loy Yang open cut. The design concept and operating possibilities of these dredgers are described in detail with reference to the machine characteristics designed for the operating conditions in the Latrobe Valley. The design is compared with units of similar capacity in open cuts of other countries.

Jan 1, 1982

By Lawson F

The Australasian Institute of Mining and Metallurgy is a society of engineers and scientists formed in 1893 (incorporated by Royal Charter in 1955) to advance science and engineering in the mineral industries, and to facilitate the exchange of information and ideas to enhance the professional excellence of its members. The Institute has several grades of members. The professional members are linked with Student and Company Members, as well as an Affiliate grade covering other professionals and non-professionals with experience in the mineral industry. The diverse group covers all sections of the mineral industry, from exploration through production to marketing of minerals and petroleum. Corporate (professional) membership also covers science and engineering professionals from specialisms other than the "traditional" ones in geosciences, mining and petroleum engineering and metallurgy. The Institute has Branches throughout Australia, New Zealand, Papua New Guinea and Oceania, whose activities complement the corporate occasions arranged for the benefit of all members by Headquarters in Melbourne. Members are drawn from all sections of the industry - private enterprise, government, research, education, and the support sector, including consultancies, manufacturers and suppliers. Membership of The Institute allows professionals to contribute to their profession through participation in The Institute's seminars and conferences, its many committees and Branch meetings, and through contribution to its many high standard publications. The Institute is the main body for the accreditation of professionals in the minerals industry. The activities of The Institute are directed towards the achievement of professional excellence. It provides opportunitites for contact with, and professional support from, colleagues, and the interchange of information on the latest industry developments.

Jan 1, 1989

The application of modern sciences prior to nineteenseventies have resulted in the placing of Continental Drift theory into broader concept of Plate Tectonics. The concept is applied to explain the Cenozoic Tectonics of North Sumatera.Oceanic crust flooring the Indian Ocean is moving northeasterly and being obliquely subducted at a Benioff zone along the western margin of Asian Plate, marked by the Sunda Trench in the west coast of Sumatera. This phenomenon was generated since late Mesozoic, continued during Cenozoic era up to present day, resulted an exellent example of arc-trench system which can be traced along SW - NE transect of North Sumatera.The oblique-subducting plate of Indian Ocean beneath Asian Plate, together with spreading of Andaman seafloor beginning in Pliocen epoch, have led to the origin of Sumateran Fault System; the System extends throughout the length of Sumatera island. In the region under review it comprises almost contiguous set of broadly SE-trending. Evidences for transcurent-dextral displacement have been observed.

Jan 1, 1990

As near surface deposits are increasingly mined out and pit widths beginto exceed the reach of practical direct-casting stripping machines, high haulage costs can make truck-shovel pre-stripping operations uneconomic. This is compounded because the rate of inflation for diesel fuel oil, lubricants, tyres, etc. exceeds the general rate of inflation. The use of conveyor transport systems, long established in terracemining operations in weak materials, e.g. engineering soils, can provide a viable haulage alternative in pre-strip operations and in some open pit settings. The paper describes the engineering requirements and basic economics of such systems.

Jan 1, 1985

A BRIEF account of the water-power potentialities of Tasmania is given, together with possible applications of the power commercially. A short history of the Waddamana development is then given, and the main works are described.WATER POWER POTENTIALITIESTasmania is an island of approximately 24,500 sq. miles area (exclusive of small islands). An area of 12,000 sq. miles is at an elevation of over 1000 ft. above sea-level, and of 2300 sq. miles at over 3000 ft. above sea-level. Average annual rainfall varies from' over 140 in. on West Coast to 20 in. on East Coast, and for the whole island averages 48.5 in. The total water-power available, based on conservative figures for run off and efficiency, is 6,000,000 b.h.p. Only a small percentage of this total will, under present conditions, and under likely conditions in the immediate future, be capable of being developed commercially.An extensive hydro-metric and water-power survey is at present being carried out in order to collect information concerning the most promising water-power schemes. Already 400,000 b.h.p. has been located in different proposals, and there is still a large area of very likely country along the West Coast which has not been investigated yet. Tasmania thus has very vast power potentialities, which, combined with good ports and communications and wonderful mineral and timber resources, should augur well for the establishment of the great key industries, particularly chemical and metallurgical.

Jan 1, 1923

Cataclysmic or flood-like release of gas-charged brines, hydrocarbons and slurries accompanied widespread mineralisation of Upper Devonian environments. These are well represented in the Canning and Burdekin Basins of Western Australia and Queensland respectively.The Burdekin Basin provides particularly instructive vein structural sequences. These fall into organic residue to carbonate paragenetic sequences which are known elsewhere to record progressive decarboxylation. Fibrous veins indicate overpressure in fractures with organic residues, acids and gas derivatives driven to overlying groundwater flows. This combination of large flow rates and potent organic mineralisers led to extensive arsenical rare-metal mineralisation which is similar to that concentrated in Upper Devonian extinction horizons of the Canning Basin. Organic-residue mineralisation appears concentrated by certain hvdrostructures and targeted upon particular species. These controls need to be understood to guide modern management stragegies for mineralised organic and nitrogenous wastes.

Jan 1, 1990

By Kyle J. H, Misra V. N

The most recent development in gold processing is the increasing use of heap leaching for the extraction of gold from low grade ore, and old tailings dumps. The reason for this trend is mainly to do with economics. The advantage of heap leaching is the considerable saving in both capital and operating costs. However, not all ores are amenable to heap leaching. It is only applicable to well oxidized ores that have suitable permeability char- acteristics, and the gold recovery is poorer than by conventional process. In this study, an attempt has ben made to ascertain the heap leaching characteristics of Western Australian gold ores on the bench scale using multiple, appropriately sized leach columns. The influence of particle size, flow rate, column depth and leaching time on the rate of gold extraction was determined. The percolation rate of cyanide leaching solution was deter- mined with and without gypsum additions. Efforts were also made to minimise particle segregation, fines migration and solution channelling during leaching, so as to improve solution percolation, gold extraction rate and recovery.

Jan 1, 1991

Samples of the feed, underflow and overflow mediums from dense medium cyclones operating at low separation densities in eight commercial coal washeries were sized and analysed, to obtain comparative cyclone classification performance curves for the magnetite, shale and coal components in the circulating medium. The resulting component classification curves indicated that the dense medium cyclones hydraulically classify the magnetite and the shale to the underflow with a Stokesian size and density relationship at these low medium densities, ie the shale curve was shifted parallel to and appropriately coarser than the magnetite curve because of the lower density of the shale. However the lower density coal reverse classified to the overflow (ie away from the cyclone wall) with a similar Stokesian relationship. By correcting the magnetite and shale classification curves for the bypass inefficiency to underflow, and similarly correcting the coal classification curves for the bypass inefficiency to overflow, the corrected classification curves for the magnetite, shale and coal were reasonably parallel (considering that the coal has a range of densities). Using a value of five for the density of the magnetite, the displacement of the shale and coal curves corresponded to densities of 2.27 and 1.38 respectively for one circuit, although the data was not as good for the other circuits. This reverse classification mechanism was confirmed in a 140 mm diameter laboratory dense medium cyclone circuit using low density (1.20 - 1.30 RD) tracers, sized from 0.25 to 2 mm. These classification performance curves were corrected for bypass ineffiency (as above). The corrected curves were parallel and displaced according to tracer density, even though the lowest density tracers were reverse classified to the overflow. The data indicate that the rates of classification of all particles could be described by the same Stokesian relationship, regardless of the direction of travel, except for a narrow band at the partition density. Particles heavier than the partition density classified to the underflow, particles lighter than the partition density reverse classified to the overflow and particles identical to the partition density were not classified at all. Consequently it should be possible to simulate partition in dense medium cyclones, operating under free settling low density conditions, with a simple cyclone classification model, provided the partition density can be accurately calculated from, or correlated with the cyclone feed, underflow or overflow pulp densities. The tracer partition performance in the laboratory cyclone was an inverse function of the tracer particle size, as proposed by King and Juckes (1984) for medium/coal ratio in low density medium systems. Their sized coal data was parallel, with lower partition values due to a higher energy cyclone. Partition data with similarly sized tracers (Scott, 1988) showed a parallel shift to higher partition values due to the separate effects of higher viscosity medium and a larger diameter lower energy Cyclone.

Jan 1, 1993

In a state-of-the-an review of predictive methods for longwall support load calculation, special respect is paid to those techniques which enable actual roof conditions and local lithology of strata to be involved. Principal systems of roof examination include the borehole perforation test and seismic velocity measurements. Roof strata stability is related to caveability classifications and roof inclination due to subsidence. The critical analysis of both load resistance prediction methods and roof stability classifications shows that each has its own value of reliability level. The present research opportunities analysed underline the significance of developing fully reliable prediction techniques as needed by the coal industry.

Jan 1, 1991

By Warren L. J

In the mineral processing industry solid-liquid separation within a thickener usually requires the addition of a synthetic flocculant to enhance the settling rate of fine particles. The characteristics of the resulting flocculated suspensions may vary considerably depending upon the physical and chemical conditions which prevail during the flocculation process. For example, parameters such as flocculant type, dosage and solution concentration, surface chemical characteristics of particles and the suspension agitation conditions can influence the degree to which the particles aggregate. Aggregated suspensions exhibit various structures, and range from those composed of small, dense aggregates to those containing large, voluminous aggregates. The size distribution and structural type of the aggregates which form within the feed-well of a thickener can have a dramatic effect upon overall thickener performance. Thickener performance cannot be optimized without optimization of the aggregate structure produced in the feed by synthetic flocculant addition. This has required the development of new techniques to quantify the nature of aggregated suspensions, details of which are presented in this paper.

Jan 1, 1989

The aquifer at Phosphate Hill, north-west Queensland, presents special management challenges. The site contains a phosphate rock mine, fertilizer plant and camp. All of the site water is provided by the Duchess Embayment Aquifer, located within the Burke River Outlier of the Georgina Basin. The Duchess Embayment is a triangular shaped, Cambrian marine sedimentary basin consisting of siliceous and calcareous phosphorites, shales, siltstones and sandstones. It is fault-bounded on all sides and has a regional dip of 5¦E. The aquifer is largely confined to the siliceous facies of the Beetle Creek Formation. It has a very flat potentiometric surface and an average thickness of 45 m with confining beds above and below. The siliceous facies derives from weathering of the calcareous phase and is highly transmissive while the calcareous zone itself contains less water and is dependent upon interconnecting fractures for its permeability. Recharge appears to occur where the siliceous facies crops out around the edges of, and within, the Embayment. Aquifer management issues revolve around two points: successful dewatering of the orebody for mining; and efficient management to maintain water quality and ensure supply over the predicted 30-year life of the project. Current operations are extracting water at levels much below that originally estimated. This is having a detrimental effect on mine dewatering with the SWL lowering at a rate slower than anticipated. As a result, ore parcels are now beginning to intersect the water table, providing a major constraint to the mining plan. The aquifer drawdown cone is extensive and very flat so to keep the water table at an appropriate level for mining the management plan will include more aggressive dewatering to lower the level of the entire aquifer. The additional water will either be disposed of downstream or stored in a holding dam or via the use of artificial storage and recharge. Water resource management will also need to maintain the current quality. About 37 per cent of the water currently extracted forms the low chloride supply required by the ammonia plant and the power station. This ratio is expected to remain applicable under any future operating conditions but the low chloride resource is restricted so will require prudent management to enable the supply to continue. At current usage rates aquifer recharge versus use will need careful monitoring to ensure that the resource remains viable in the long-term.

Jan 1, 2003

By Scott A

The object of most blasting operations is to destroy the insitu structure of the rock mass so that mechanical equipment can efficiently excavate the rock fragments. In achieving this objective the blasting engineer is also concerned with minimising damage to the adjacent rock which forms the mine structure relied upon to provide support. Damage to this "structural" rock is undesirable but usually occurs as a result of two distinct processes: ò readjustment of stresses around the excavation as a result of the mining process itself ò impact of vibration and high pressure gases from blasting operations. Gross damage to mine structures from either cause is observed as visible alteration to the appearance of the rock structure in the form of cracking, slabbing, back or over break and visible displacement. Recent work at the Julius Kruttschnitt Mineral Research Centre (JKMRC) has shown that significant reduction in the strength of a rock mass can take place well before the onset of these obvious signs of damage. It has been demonstrated that the effect of blast damage on the behaviour of the rock mass can be many times more prominent than the effect of stress redistribution. This offers the blast design engineer the opportunity to significantly reduce blast induced damage to rock structure by modifying blasting practices. This paper introduces the current JKMRC postgraduate research projects investigating the evaluation and control of blast damage.

Jan 1, 1990

By Corbett GJ

Comparisons between individual SW Pacific Rim gold deposits have facilit-ated proposal of a new classification of porphyry-related mesothermal gold deposit types. Carbonate base-metal gold systems form at relatively high crustal levels, peripheral to porphyry intrusions. There is a spatial assoc-iation with major structures which focus fluids from degassing porphyries at depth. Milled matrix intrusive breccias and extrusive maar volcano/ diatreme breccias form as a result of pre-mineralisation phreatomagmatic eruptions. These focus degassing magmatic fluids by the provision of fracture ground preparation, typically within competent host rocks, adjacent to the breccia bodies. Local dilational structures control the form of individual deposits which may contain bonanza gold grades at sites of fluid quenching and/or repeated mineral deposition.Early quartz veining and porphyry-related alteration is common and later gold mineralisation typically occurs in association with carbonate veining and Fe and base metal sulphides as Zn > Pb > Cu. The progressive cooling by mixing of the upwelling mineralised magmatic fluid with descending bicarbonate waters, produces characteristic zonations in carbonate compositions. These vary with distance from the porphyry source, from Ca through Mg, Mn and distal Fe types. Gold mineralisation is preferentially distributed within the Mn/Mg carbon-ates.

Jan 1, 1994