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The unique characteristics of the Target orebody and modernistic approach to mining present significant challenges and a concomitant high potential for new opportunities. The break-away from the traditional labour intensive mining methods improves both safety and productivity significantly. The intention of the paper is to illustrate the application of well known mining methods to the particular requirements of a complex orebody at depth. The evolutionary process followed to establish the final mining method design provides insight behind the finished product, and the modern approach to the planning and service principles equips the reader with a suite of mining engineering ideas.

Jan 1, 2000

By J Walasiak

In the climate planning of mines and tunnelling with anticipated poor climatic conditions, and especially in case of longer working shifts, the main question is whether it can be reliably prevented that certain climatic limits laid down be exceeded. Working at high temperature and/or humidity can lead to reduced human working energy û a very important economic aspect û and to a risky lack of concentration on the part of the miners or to heat collapse and extremely dangerous heat stroke. With the Deutsche Montan Technologie GmbH (DMT) climate prediction programs, both the dry and the extremely significant humid heat transfer can be calculated. This is due to the high planning reliability involved. With the help of these climate prediction programs it is already possible to determine the anticipated climatic values for the operation phase as early as the planning stage of new ore or coal fields or of tunnel construction projects and to design the optimum air cooling system for every underground project with due regard to technical and economic aspects.

Jan 1, 2005

By Opitz E. A

The integration of environmental and permitting strategies into development has become a routine part of doing business for the international minerals industry. Paralleling the development schedule with the environmental and permitting schedule is critical to ensuring that design recognises environmental constraints and that the environmental and permitting program has the right focus and achieves the objective of obtaining workable permits that reflect the project design. Regulatory issues including the law of and controls established by the country the project is situated in, the requirements of international financing institutions, international politics and the role of environmental groups and the particular precedents and processes established are all important issues that must be recognised and incorporated into the permitting program by the developer. Technical issues including collecting early environmental data during exploration, establishing hydro-meteorology equipment, baseline data gathering, and getting good environmental engineering information as a part of feasibility and design are also critical issues to the success of a project which are under the direct control of the developer. Finally tying all of these issues into a single integrated strategy under the direction and control of a nominated team is necessary to maintain focus and achieve results.

Jan 1, 1997

By S Pontual

Compact and field portable infrared spectrometers have been increasingly used over the past few years by an exploration industry constantly searching for a technological edge and the ability to more accurately and rapidly assess project areas. In particular, this technology allows large amounts of data to be rapidly collected on-site and sample mineralogy, mineral crystallinity and mineral composition to be quickly assessed. In recent years, short wave infrared (SWIR) reflectance spectroscopy has proved useful in a wide range of geological environments and at various stages of exploration programs, from grass roots reconnaissance through drilling programs and resource evaluation. Unfortunately these data have frequently been analysed and interpreted in isolation using time consuming data analysis techniques removed from the realities of a fast moving exploration industry. This paper presents new analysis techniques which allow these data to be efficiently integrated in the exploration program. Although SWIR data contain a wealth of mineral information it is impractical to use this information in its raw form. A more effective approach involves the extraction of key characteristics of these data (ie mineralogy, mineral composition and crystallinity) as numerical values, and the integration of this ædigital mineralogyÆ with more conventional exploration datasets (eg geochemistry, coordinate data, etc). This paper demonstrates that the integrated analysis of sound geological observations, geochemical, spatial and spectral data can quickly lead to a greater understanding of the nature and distribution of target mineralisation. As a first step, software driven pattern matching routines enable the identification of the major clay mineral species in a series of samples (eg kaolinite, montmorillonite and sericite). This allows the major alteration facies and their spatial distribution to be identified. Quantification of diagnostic absorption feature characteristics then allows more accurate determinations of mineralogy to be made (eg mineral composition and crystallinity). Examples of the application of SWIR analysis for alteration mapping from selected porphyry and epithermal systems from around the Pacific Rim are discussed. The data presented are derived from a variety of locations and sample types including drill core, ridge and spur rock chip samples, soil samples and geochemical pulps. In these large alteration systems, the spectral data can be used to describe and map the distribution of various alteration facies as many of these are characterised by clay and phyllosilicate mineral assemblages and are detected by SWIR analysis (eg smectite, chlorite, biotite, illite, muscovite, kaolinite, dickite, pyrophyllite, alunite, etc). In addition, the ability to evaluate even subtle trends in mineral crystallinity and composition is often vital in these systems when looking for vectors towards higher temperature parts of the system. In addition to detailed evaluation of mineralogy, the integration of digital mineralogy data with geochemical data leads to the ability to describe not only geochemically anomalous intersections or regions but also to recognise associations between subtle changes in mineralogy and target mineralisation. This is often important because understanding these mineralogical associations can lead to more accurate targeting and rapid assessment of the project.

Jan 1, 1999

The characteristics'of the Darling Range bauxite deposits are compared with tho"se of other large deposits in Australia and over seas The Bayer Process is them described with particular reference to the way.in which the process has been adapted to suit Darling Range bauxite. The.main characteristics considered are the physical aspects of the deposit.and its' effect on mining techniques, the grade of the ore and its effect on residue treatment, the nature of the alumina, iron and silica. content and their effect on process methods, equip- ment and raw material. Usage.

Jan 1, 1973

The current boom conditions in the Gold Mining Industry, open cut low grade gold mines have become the initial cash flow source for most companies. To achieve the required cash flow the head grade needs to be maintained at the required level. The methods of grade control to achieve .the planned head grade have evolved various systems, one of which is the Ditch Witch Trencher. The application of this machine has revolutionised open cut grade control and Geology and this paper records the various methodologies developed in the Eastern Goldfields of Western Australia.

Jan 1, 1987

By A C. Robertson

Over the past decade there has been continual change in the way that mines have been managed and the component roles of those people who make up the total mine management system. Major issues have included the change in the business structure of mining companies, the change in on-site infrastructure, increased personal liability of managers for the safety and health of employees and increasing social and environmental pressures on managers and their staff. This paper looks at the changing roles of two of the many groups of professionals associated with the mining industry - the equipment supplier and the mining consultant. The profiles of the ACME Group Pty Ltd, suppliers of ventilation equipment and ancillary canvas and plastic products to the mining and construction industry, and Tennent, Isokangas Pty Ltd, Consulting Mining Engineers, are presented.

Jan 1, 1998

By S Pfaff, R Rajic

In the case when the number of independent variables is greater, a careful design for carrying out tests has to be made in order to obtain, with the smallest possible number of tests, as much as possible neutral information about the influence of independent variables on the dependent ones. Only on the basis of such design and its statistical analysis it is possible to come to right conclusions about the function of the whole system. The influence of pressure, temperature, humidity and granulation of the coal upon the resistance to pressure and the water absorption of the briquettes has been tested, with the aim to examine how each of the two dependent variables changes depending on the values assumed by any of the four independent variables and which of the mentioned independent variables significantly influences the dependent ones. The full factorial design with 16 experiments and the central composite design with 27 experiments have been applied. The influence of the independent variables upon the dependent ones has been examined by applying the analysis of variance. The influence values of individual factors and their interaction upon the dependent variables have been stated as well as coefficients of curvilinear equation.

Jan 1, 2003

By Cox A

A key concern both in public perceptions of the environmental performance of the mining industry and in the development of policy relating to mining activities is the state in which the areas may be left at the completion of mining operations. There is, in effect, concern that the transient economic benefits of mining are enjoyed by the few, while the 'scars' may remain for all. While the techniques of mine rehabilitation have improved rapidly in recent years, an important set of economic issues has generally been neglected.In this paper, the economic and policy aspects of mine rehabilitation are examined. The key issue addressed is how to determine when expenditure on rehabilitation should stop. The answer to such a question requires consideration of the full range of social, as well as private, costs and benefits of rehabilitation at a particular site. Clearly these costs and benefits will vary between sites. From both an economic and policy perspective it is important to establish whether the additional gain from more rehabilitation would exceed the additional cost.It is concluded in the paper that the technical feasibility alone does not justify a paeticular level of rehabilitation activity and expenditure. While more rehabilitation at a particular site may be technically feasible, the additional expenditure incurred in undertaking that rehabilitation may result in little extra benefit. This conclusion has important implications for government policy, particularly with respect to establishing the goals for rehabilitation, criteria for successful rehabilitation and enforcement of rehabilitation objectives.

Jan 1, 1992

By S Williams

The primary objective of most mining projects is to maximise the value delivered to the companyÆs shareholders. Achieving best practice performance and maintaining competitive advantage through low-cost production and high productivity is essential to achieving this aim. Benchmarking is an essential tool for the identification and implementation of best practice performance, and to realise continuous improvement by ensuring best practice becomes common practice. But to be successful, that is to deliver long-term value creation, benchmarking must be holistic and align operational performance with strategic intent. This paper outlines a rigorous and structured approach on how to conduct a successful benchmarking program that aligns operational performance with the businessÆs goals. Further it investigates the benefits that benchmarking can provide throughout the project life cycle and provides some key learnings from some of the worldÆs leading miners.

Jan 1, 2009

This paper is a tribute to the late Dr Donald Martin Hausen as a father of applied mineralogy. His dedication to promoting the field through technical societies and through his professional work was outstanding, and his activities as a humanitarian are noteworthy. Dr HausenÆs involvement in technical societies included organising and conducting the only ICAM congress that was held in the USA, co-founding and nurturing the Process Mineralogy Committee within the American Institute of Mining, Metallurgy and Petroleum Engineers, and participating in CAM, the International Mineral Processing Congress, as well as other technical societies. The Process Mineralogy Committee that he co-founded has continuously organised annual meetings in the USA by conducting a series of sessions, and 17 books on the proceedings from those sessions have been published. As an applied mineralogist Dr Hausen solved many problems in exploitation and processing of minerals, metals and materials, especially gold. He helped to find many Carlin-type gold orebodies by outlining targets using alteration halos as determined by X-ray diffractometry, and he defined mineral characteristics that affected gold metallurgy and cyanidation. It is also noteworthy that Dr Hausen and his wife, Mary, opened their arms and home to many foster children and were instrumental in their placement in many homes. They also sponsored refugees from south-east Asia, taught them English, housed them, and provided constant support until the refugees became responsible and independent US citizens.

Jan 1, 2008

By Fitter JF

Drilling and blasting practices at Groote Eylandt are undergoing a period of rapid change. Practices over the last ten years are reviewed and some specific blasting problems currently being faced are described. A move from percussion to rotary drilling is outlined, together with the reasoning behind a proposed return to ANFO from watergel explosives. A brief outline of the various firing patterns used is given, together with a description of the drilling and blasting recording procedures currently in use. Current and planned developments in drilling and blasting at Groote Eylandt are also outlined, emphasizing the success of wide patterns, fired in line with long inter-row delays.

Jan 1, 1982

AustraliaÆs record-breaking drought, efforts towards environmental best practice and the current commodities boom is demanding water use and reuse as never before. Mining practices, processing, the remote communities and support industries require vast amounts of specific quality water. Sustainability of water use has been a key factor in mine development, expansion of existing operations and increasing profitability of processes involving water. Developments in water treatment technology have enabled the use of a range of processes to produce this water reliably at ever decreasing costs. This increasing acceptance of new technologies has seen seawater desalination, recycling of plant wastewater streams, municipal wastewater reuse and others to become commonplace. Processes including seawater and groundwater reverse osmosis (RO), low pH RO, thermal desalination, high rate clarification, brine water treatment, ion exchange and other advanced treatment technologies are now used as part of mining operations. This paper surveys the trends in water treatment for the mining industry both in Australia and internationally with a review of technologies and case studies of operating plants. The key technologies are explained with an emphasis on the specific requirements for mining operations û unusual raw water, process and operations limitations, environmental concerns, as well as harsh climate. Case study information from several mining operations is included.

Jan 1, 2006

The use of black and white and colour infrared film in remote sensing of natural resources, is reviewed. In heavily-forested areas such as New Zealand, the main value of the method is in surveying the vegetation cover to detect the existence of plant communities characteristic of specific geological formations, By contrast, in and areas of Australia where the vegetation cover is sparse and where rocks and soils are well exposed, the method can be used in detecting different rock types or other geological differences.

Jan 1, 1971

By D S. Scovira

The effect of blast vibration on highwall stability is a common concern for many open pit mines. Vibration in such a case is a typical near-field blast vibration situation. Vibration modelling in the near-field of a blast requires consideration of both the amplitude and frequency attenuation of waveforms with distance. Most existing blast vibration models are designed for far-field vibration and do not simulate the frequency attenuation and its effect on waveform shape. With the advent of electronic detonators it is desirable to quantify the effects of blast delay on the amplitude as well as the frequency of blast vibrations. A suitable modelling tool is proposed here. At present, a blast vibration model with double attenuations(amplitude and frequency) has been developed at Orica. The present model simulates the amplitude and frequency attenuations separately using different transfer functions. The amplitude attenuation is modelled according to the non-linear relation between the peak particle velocity (PPV) and the charge weight scaled distance established from the signature hole vibration. The frequency attenuation is modelled with the signal broadening based on KjartanssonÆs transfer function û a linear model for attenuation of waves. The model is capable of taking multiple sets of signature waveforms as input to improve the modelling accuracy of the wave propagation in the geology at a site. The screening effect of the earlier firing holes in the path of a later firing hole is taken into account on not only the amplitude, but also frequency attenuation. The present blast vibration model is suitable for modelling both near-field and far-field blast vibrations. It yields reasonable agreement with measured field data for the near-field vibration examples discussed.

Jan 1, 2007

By Van Rooyen F

An introductory review of the current grade control blasting techniques (selective mining strategies) used in the Eastern Goldfields has recently been undertaken. The survey was initiated and conducted by the Western Australian School of Mines. Four distinct selective mining strategies have been identified and a number of trends have been highlighted. Many operations, however, have developed techniques which use a hybrid method to suit the site conditions. The aim of all the mining strategies is to produce an optimum product. The optimum product is one which contains no diluent and experiences no mixing of the various identified ore and waste blocks and is fully reco- vered at the minimum overall operating cost. Due to this unified aim all of the grade control blasting techniques have many common design Features.

Jan 1, 1988

By Komosa T

The increase in the proportion of sulphide ore treated by the gold mining industry has led to generally higher oxygen requirements. Additions of pure oxygen, hydrogen peroxide and in some cases calcium peroxide, have been proposed as a means of satisfying the oxygen demand and overcoming the problems from reactive sulphides in the ore. Current oxidant addition options and practice are reviewed.Laboratory oxygen demand tests are reported for a suite of ores to show some of the effects of pH and preaeration.Laboratory leach tests at high and low dissolved oxygen levels are reported on two of the ores with higher oxygen demands, and the results are assessed in terms of gold leaching kinetics, ultimate gold extraction, and cyanide requirements.

Jan 1, 1992

Callide Coalfields produces a sub-bituminous, very subhydrous, low rank, steaming coal with good combustion properties, primarily for domestic power generation. Geological input into planning of coal extraction requires expedient production of detailed structural, lithological, analytical, geophysical and geotechnical data. The CSIRO-developed SIROLOG borehole logging software and hardware system allows for detailed spectrometric analysis of coal/interburden. The gamma-gamma and neutron-gamma SIROLOG techniques both provide improved prediction of ash content over other borehole techniques. The neutron-gamma technique also predicts density and some important ash constituents (especially iron, alumina and silica). The software/hardware configuration allows for quick, easy interpretation of coal seam depth and lithology, parting thickness and ash/ash constituent contents immediately after a borehole has been logged. Within certain mine areas in the Callide Basin, the iron content of mined coal is widely variable in both vertical and lateral extent within and between seams. This variability creates problems in predicting the slagging behaviour of æas-receivedÆ coal during combustion, especially where the iron content of the ash exceeds 19 per cent. Using the SIROLOG tool in co-operation with traditional borehole sample laboratory analysis results, patterns in this variability can be determined and related to geological properties and process of formation of the coal seams. Subsequently, areas of high iron can be predicted in advance of mining. Since 1992, on-going collection and interpretation of SIROLOG downhole geophysical log data has significantly contributed to a number of research projects related to gaining a preliminary understanding of the iron distribution and formation during the Coal MeasuresÆ deposition. Because the probe was able to record variations in coal mineral matter content, it was found to complement more conventional techniques such as reflected light petrography, X-Ray Diffraction and SEM techniques that examine the mineralogy of iron species. Additionally, software has been developed to allow integration of SIROLOG data into existing geology databases, enhancing coal quality modelling and daily prediction of parameters such as raw ash, silica and iron contents that are indicators of ash fusion propensity. The correlation of SIROLOG-derived iron geophysical traces between drillholes and other sample points highlighted lithological and structural controls in the iron distribution in the sequence previously not detected. This work has allowed the development of a methodology for predicting iron in advance of mining and reconciling as-sold coal quality to that predicted. Predictions are currently being assessed at the coal face as mining progresses through high-iron zones.

Jan 1, 2000

Coal mining in the Illawarra commenced in 1848. By the early twentieth century mining operations were spread over quite a distance along the coast centred on Wollongong. By this time there were already numerous tunnel mines and one shaft mine. Coal was first reported in Illawarra by Lieutenant Flinders on a voyage of exploration, southerly along the coast from Sydney in 1796. Because of the topography, particularly the escarpment and the narrowness of the coastal plain, access from Sydney was not easy by land and the normal access was by sea. It was not until some coastal areas had been developed for agricultural purposes that the mining of the seams on the South Coast commenced for the supp- ly of fuel. The most important mines in the early nineteenth century were Bulli and Osborne Wallsend. In general, coal was won from the tunnel mines and was transported directly, usually by tramway, to the nearest shipping point. Considerable hardship attended the earliest attempts at mining coal in regard to materials for mining and the way of life of the miners in the vicinity of the mines. With the growth of production and the installation of coke ovens at some mines the area, hitherto virgin bush- land, began to take on a more industrialised appearance. The mines were necessarily small,

Jan 1, 1976

By Hyde L. J

Blasting is one of the available technologies to be employed in underground excavation systems. In many instances it can be the only technology which is suitable. The recent moves towards more mechanised working systems is resulting in a reduced awareness of new blasting practices and technologies on the part of many excavation engineers. Recent developments in blasting systems can be utilised to significantly improve operating efficiency, reduce total cycle times, better comply with regional environmental constraints and reduce the total cost of underground excavation. Blasting is and will remain, a very adaptable and exciting alternative which is far from boring.

Jan 1, 1987