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By Trendell B

While objective selection and assessments are an accepted part of employing managers and other staff, they have had only a limited place when selecting mineworkers in Australia. Wambo Mining Corporation has used occupational testing as part of its recruitment process since 1994. For managers and staff in particular, it is considered this has contributed significantly to a 95 % fit of those appointees. In 1997 when Wambo undertook development of a new "on site" subsidiary underground mine called Wollemi Services, they wanted to select the most appropriate people in terms of skill and on the job performance. To achieve this they reviewed and improved their recruitment processes to facilitate selection and transfer of an initial intake of almost 50 staff and mineworkers.One of the issues for Human Resource Management was to provide an environment where employees could let go of previously held (but not necessarily individually believed) entrenched views about individual performance and assessment. It needed to be emphasised that performance could be objectively and fairly assessed. More importantly, the performance being assessed was the application of skills and that new skills could be learnt and individuals could choose to change Behaviour.

Jan 1, 1998

By R R LARGE

In the past decade mineral deposit models have become an important tool for the exploration geoscientist. By combining genetic theories on the formation of particular deposit styles, with geological, geochemical and geophysical criteria relevant to ore location, it has been possible to more effectively focus exploration effort to the regions and local targets which have the best chance of success. However, such models have their limitations, and must be carefully and critically applied and continually updated as new technical and research information becomes available.

Jan 1, 1992

By S Fidler

Underground coal gasification (UCG) is a process by which coal is converted in situ to a combustible gas that can be used as a fuel or chemical feedstock. The process has been used in commercial-size projects in the former Soviet Union for more than 40 years, while significant national research programs have been undertaken in the United States and Western Europe. The Chinchilla UCG project is located at a site southeast of Chinchilla in Queensland. The UCG operation commenced in December 1999. A controlled shutdown of the process was initiated in January 2002 and successfully completed in April 2003. The process is currently under conservation and ready for restoration of gas production for commercial use in the near future. Groundwater plays an important role in the gas formation process during UCG. Most of the process water required for chemical reactions is usually derived from the coal seam itself and from surrounding aquifers. If insufficient water is available for chemical reactions the UCG gas will contain reduced concentrations of combustible components, and conversely, excessive water influx into the process area would cool down the reactor and thus limit the energy available for gas production reactions. Because of the importance of groundwater in the gasification reactions, and the potential to contaminate groundwater if the process is not correctly controlled, it is essential to predict and to control the groundwater influx into underground gasifiers during and after underground gasification. Control of groundwater requires a thorough understanding of hydrogeological conditions in the vicinity of the gasifier in order to be able to predict inflow rates, and constant monitoring throughout the process of water production rates and groundwater pressure in the coal seam and adjacent aquifers. Hydrogeological testing and groundwater monitoring in the vicinity of the UCG operation commenced six months in advance of its initiation. Monitoring of groundwater pressures in the vicinity of the gasifier have also been undertaken using vibrating wire piezometers installed in the coal seam at varying distances from the gasifier. This paper presents the results of the hydrogeological testing and groundwater quality monitoring carried out at the site, which show that it is possible to operate a UCG process without uncontrolled impacts on groundwater.

Jan 1, 2003

By G Giles

One of the main tools used by mining operations to mitigate the risk of rock burst is the installation of a so-called ædynamic resistantÆ support system. Such systems are designed to absorb the impact of shockwaves created by mine-induced seismic events. Dynamic support must be strong and capable of sustaining high loads and, at the same time, they have to be flexible and accommodate large deformation. A dynamic support system is therefore a system capable of absorbing a high quantity of energy. Ground support systems are composed of rock reinforcement (rock bolts or cable bolts) and surface support (mesh or shotcrete). In terms of surface support, fibre-reinforced shotcrete is increasingly seen as the industry preferred solution when difficult ground conditions are experienced, including areas of high seismic hazard. A thick layer of shotcrete is certainly strong but it is by no means flexible. Normal weld-mesh has some flexibility, but it is not very strong. The Australian Centre for Geomechanics (ACG), in collaboration with Onesteel Reinforcing Pty Ltd, is currently working on a new high-energy absorption mesh that combines strength and flexibility. The new mesh can be installed with a jumbo, in a similar way as the widely used sheet of weld-mesh. This paper describes the development of this new mesh system.

Jan 1, 2008

By S Ramsay, D Povey

This paper presents recent case study data collected by field portable x-ray fluorescence spectrum analysers (FPXRF) as part of grade control activities at three separate (nickel, copper and copper/gold) mining operations. FPXRF has been under utilised for grade control in recent years, largely because the success of early versions of FPXRF was limited to a few metals (eg tin). Efforts to utilise these early versions for other metals was largely unsuccessful and created a perception that FPXRF could not be utilised more broadly within the mining sector and specifically the area of grade control. The structural setting of the analytical function within mining operations has also contributed to the under utilisation of more recent FPXRF instrumentation. The concept of FPXRF as a grade control tool straddles the boundaries of the geology and laboratory departments. As such, this option is often not considered as part of an assessment of grade control procedures for new and existing mining operations. This paper assesses data collected by Australian and New Caledonian miners using FPXRF technology as part of the grade control function and concludes that FPXRF can provide operational and cost benefits to certain mining operations.

Jan 1, 2003

This paper describes an ongoing study into the management systems developed by mining operations in Papua New Guinea to address particular public health issues in the workforce (primarily communicable and lifestyle diseases). The first stage of the study involves the analysis of the site health and safety management system documentation of three major mining operations in Papua New Guinea, producing a descriptive summary of each system. In the second stage of the study these summary descriptions are evaluated using a maturity model constructed through a detailed review of literature. Experience with the evaluation process is then used to refine the maturity model. The analysis performed in the study is used to develop a process for creating a maturity model for mine site health risk management based on a theoretical risk management framework, and refining it through empirical evaluations of the actual systems in place on site. Companies can use maturity models as a guide to organisational improvement, which in the context of the study will assist the operations in developing their systems for the management of health both in their workforce and in local communities.

Jan 1, 2007

By Keren Z, Huanguo G, Jlchuan Q

In this paper, the authors introduce a new flotation technique, a double collection flotation precess, which succeeds in separating feldspar from quartz effectively in weak acidic medium (pH = 5-6). In the presence of sodium hexametaphosphase(HMP), sodium oleate selectively improves the floatability of feldspar in the first collection step. Dodecyl amine- hydrochloride is used as collector in the second collection step to separate feldspar from quartz. The flotation tests with pure minerals as well as artificial mixture give out satisfactory results. The mechanism of reagent effect was investigated briefly, which is helpful for understanding the Process.

Jan 1, 1993

The End of the Line for Roadway Development By Michael Kelly, CSIRO Exploration & Mining Michael Kelly highlighted that roadway development performance remains one of the threats to expansion of Australia underground coal exports to the growing Asian market. In a recent industry study, automation was highlighted as one of seven strategies for roadway development improvement. Growing Asian markets The expansion of the Asian coal market is a long term driver for expansion of the underground coal industry in Australia - if significant productivity improvements are made. Imports of steaming coal by Asian APEC members are predicted to rise by from 150 MT to 190 MT. Australia is one of the few countries which has a potential capacity larger than predicted internal needs. Predictions are for exports of black steaming coal from Australia to increase from 50.3 MT in 1992 to 106.3 MT in 2010. To meet this prediction, an investment of $10.7 billion (in 1992 dollars) will have to be made in mining and transport facilities. This is equivalent to the opening of a major new mine each year until 2010. Many of these mines will be underground operations. However, much of Australia's capacity to respond to increased Asian demand will depend on its ability to develop underground technologies and improve productivity. The inability to make sustained improvements in roadway development rates has to date been one of the main reasons why new underground projects have failed to deliver the expected returns.

Jan 1, 1997

In the future, Illawarra Coal, the primary metallurgical coal producer in the southern coal fields of New South Wales, will face many unique challenges not found in other coal or minerals production areas. To manage these challenges and determine the best strategy for the business, Illawarra Coal has adopted a systematic strategic planning process, which starts from the broadest possible options analysis and culminates in a ægo-forwardÆ operating case that individual mine sites use as the basis for short-term planning. This paper will discuss two major topics. Firstly an overview of the Illawarra Coal and BHP Billiton strategic planning processes. This will demonstrate the range of variables and inputs that are required for the planning process, and the system which is followed to evaluate different alternatives for the extraction of the resource. Secondly, having discussed the primary external and internal factors that must be accounted for in the planning process, and the main issues affecting the viability and likelihood of each alternative, the paper will discuss the particular challenges that Illawarra Coal will face in the coming decades. These challenges include: market and price uncertainty; managing impact on surface features, infrastructure and environment; community interaction; transport and logistics constraints; unknown mining environments; lack of geological knowledge; limited surface access for new mining domains; changing attitudes to longwall mining in the Illawarra; ageing workforce; and cost and overhead management. The paper intends to discuss how these issues impact the business currently and how they are incorporated into Life of Asset plans and overall corporate strategy for Illawarra Coal.

Jan 1, 2007

The Australian Mineral Industries Research Association, set up by the mineral industry in 1959, acts as a research and development broker and manager for the industry. In 1984/85 it contracted out just over $3 million of projects. Its structure and method of operation is described and highlights of some of the successful projects are given. The complex process of developing new proposals is described. This involves the establishment of effective communication networks within the industry and between the industry and research personnel working outside it. The advantages of the industry tackling some of its problems on a jointly sponsored basis are listed. Possible avenues for future development by the Association are given.

Jan 1, 1986

By Hatherly P, Dunn P

There are- several in-seam coal research projects currently under investigation by the Cooperative Research Centre for Mining Technology and Equipment (CMTE). The overall aim of the projects is to produce new technologies to enhance safety and the efficiency of in-seam gas drainage drilling. Results from high pressure waterjet rotary drilling trials indicate that by applying high pressure water to a rotary drill bit, the hole can be drilled to follow the planned trajectory very closely. Steerable drill bits for drilling long holes (>1 km) have been produced and trialed. A flexible high speed drilling system provides a capacity for rapid in-seam drilling, particularly suited to cross panel drainage. Geophysical tools are being developed to provide a geological steering capability and a better understanding of potential gas outbursts zones.

Jan 1, 1998

The lignite mines in the Latrobe Valley of Victoria/Australia have been using continuously operating mining systems for more than 50 years. The relatively small bucket chain dredgers of the early years have been progressively displaced by bucket wheel dredgers with increasing size, increasing capacity and increasing service weight. The large machines for the new open pit Loy Yang have a bucket wheel outreach of 46m, an effective capacity of 3350 bm' coal/h respective 2500 bm' overburden/h and a serv- ice weight of approx. 4500 t. The time between signing of con- tract and starting of operation for these machines is at least four years. The high service weight, the resulting high capital invest- ment and the long period for design, design review, manufac- turing, erection and commissioning of these machines directed the SECV to investigate a possible application of compact dredgers for the Latrobe Valley.

Jan 1, 1989

By Kelly E. G

New Zealand suffers the disadvantage of widely scattered ore bodies, none of which is large enough to economically support its own smelter. This leads to the concept of a centrally located smelter which must be flexible enough to cope with var

Jan 1, 1980

By Dr Subagyo

The energy consumption for producing metal from ore is strongly linked to the chemical stability of mineral being processed, availability and richness of the ore, and process route. Energy efficiencies are particularly linked to the process route. The energy efficiency of high temperature operations vary considerably but energy efficiencies greater than 70 per cent are achieved for large-scale metal production. Low temperature processing through grinding, leaching and subsequent electrowinning use large amounts of energy. In particular, grinding and electrowinning suffer from low overall energy efficiencies. The physical chemistry of a new proposed low temperature route, reactive ball milling, is unclear but preliminary evaluations indicate that it is likely to suffer from high energy consumption. In conclusion, low temperature processing routes for metals generally consume more energy that comparable high temperature processing routes.

Jan 1, 2002

By I Grant

On the 1 June 1978, the Town and Country Planning Act 1953 was replaced by the revised and more comprehensive Town and Country Planning Act 1977. The new act brings in some substantial changes to the law affecting regional and district planning, and for the first time makes provision for maritime planning. The importance of the Town and Country Planning Act 1977 to the Mineral industry is primarily in the relationship between Regional Planning Schemes and District Schemes as the needs and resources identified in a Regional Planning Scheme will override the underlying District Schemes. The mineral extraction industry must be recognised as a regional responsibility which draws on the resources of a region to satisfy the demand of the communities within that region rather than a purely local operation within one District.

Jan 1, 1978

The increasing use of Ditch Witch trenching to define gold ore bound- aries in supergeme enriched near surface open cut mines has led to the consideration of using this technique for other sampling procedures. The use of Ditch Witch trenching for exploration has not been widely used and it is anticipated that the technique described will help stimulate more extensive use and new sampling techniques.

Jan 1, 1988

Solid Energy New Zealand (SENZ) uses a 20+ year period for integrated planning of all its business activities. It has an ongoing program of coal resource assessment to optimise future mines within this 20 year period, using a six step resource and mine planning process. Desktop review and conceptual study at preliminary Levels 1 and 2 are based on general coal resource information. Further coal resource investigations are carried out for the more detailed evaluations in secondary assessment, prefeasibility study, feasibility study and detailed engineering from Levels 3 to 6. At Levels 1 and 2, completing conceptual planning, including preliminary resource evaluation and economic appraisal to the target cost uncertainty level of ¦33 per cent, is challenging in New ZealandÆs highly variable geological and geographical conditions. Where coal deposit geometries are relatively simple, approximate methods for determining pit limits using overburden strip ratios, seam thickness, physical boundaries, and quality cut-offs may be sufficient. Many New Zealand coalfields are however complicated structurally, with multiple seams and extensive folding and faulting. Coal seams are characterised by variable dip, thickness, and quality over relatively short distances. In the North IslandÆs Waikato coalfields, coal is typically overlain by weak sediments and clay rich strata that necessitate very flat cut and fill slope angles. The proximity of these deposits to major infrastructure (including towns, highways and rail lines), significant environmental features such as the Waikato river and lakes, and valuable dairy farmland, add further complexity. Traditional preliminary mine planning techniques applied in these conditions are insufficient. Pit optimisation software, widely used in the metalliferous mining industry since the 1980s, offers the ability to analyse many more specific factors affecting pit limits, mine layouts, and economics, with more rigour and for a much larger number of scenarios, than traditional methods allow. SENZ therefore decided to adapt and use æWhittleÆ pit optimisation software for Level 2 analysis of several Waikato opencast prospects. This paper describes this work.

Jan 1, 2005

By Itoh K, Sakai K, Tsuji K

In Japan there exists a strong demand for mechanical excavation for tunnelling bacause the blasting method which produces much vibra- tions and noises is restricted in its applica- tion due to the fact that there can be many cases where tunnelling sites are located ad- jacent to residencial areas as a result of Japan's being a thickly inhabited country. Pressing demands for and deep interest in the mechanical excavation method have been shown by the circles concerned with reasons that it produces smooth cutting surface and causes less overcutting of profile as a result of the diffusion of NATM (New Austrian Tunnel- ling Method) in the recent years. This has caused a strong desire of the users to apply the conventional mechanical excavation method that has been used mainly for soft rock cutting also to the field of hard rock cutting. In order to meet such needs of the tunnel- ling industry, further research and development have been continued to have successfully real- ized the Boomtype Tunnelling Machine for Hard Rock.

Jan 1, 1987

Computer programs for the storage, retrieval and use of basic thermodynamic and physical property data for chemical substances are described. Methods are presented for the collection, critical assessment and pre- processing of source data for files containing enthalpy, entropy and heat capacity data for 3000 compounds, enthalpy and excess entropy for 200 dilute solutions and critical propert- ies and vapour pressure for 600 compounds. Retrieval programs are discussed which allow the tabulation or plotting of many basic and derived thermodynamic properties for chemical substances or balanced reactions. Examples are given of the use of such data to infer the stability or corrosion resistance of materials and the feasibility, yield and heat release of reactions. A general purpose calculation program is discussed which allows the equilibrium compos- ition to be found for complex systems with many species and phases, using the method of Gibbs energy minimization. Methods of correction for non-ideal behaviour in these systems are discussed, as well as methods for fixing, maximizing or minimizing any desired property of the system. Examples are given of the simulation of various laboratory Experiments and industrial processes by this method.

Jan 1, 1977

By Bigdy D. N

The paper describes a system for providing mine management with a continuous indication of the effectivness of longwall coalface powered supports in controlling roof-to-floor convergence. The system comprises on-face instrumentation monitoring convergence and support leg circuit pressures, a means of transmitting the output of that instrumentation to the surface for collection, and software which presents both a condensed analysis for rapid review of the current state, and extended analyses from which remedial action can be recommended if a problem is identified. The results of a field trial are presented showing that meaningful results can be obtained.

Jan 1, 1988