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By T D. H McGrath, G Wardell-Johnson, E A. Oraby, W Staunton, A R. Bax, J J. Eksteen

"Gold ores often show significant inter-domain variation with respect to the gravity recoverable gold (GRG) content and the leach behaviour of the non-GRG component. Liberation assessment is extremely difficult for gold due to its malleability and the high sampling errors and poor test reproducibility resulting from gold’s high specific gravity and the low metal concentrations that occur in most gold ores. The use of microscopic techniques for the liberation assessment of gold is also impractical due to the high number of sampling errors and high cost of analysis.Curtin University’s Gold Technology Group has developed an online carbon-in-pulp/carbon-in-leach (CIP/CIL) simulation model called SIMCIL, which has been used since 1999 to model and simulate industrial leach-adsorption circuits. Recently the model has been upgraded to include an integrated liberation-leach modelling (ILLM) approach, which can be used to evaluate the impact of various process parameters (such as grind size, bleed to gravity etc) and circuit configurations on leach-adsorption circuit behaviour and overall plant gold recovery. A new time-efficient ore characterisation methodology has been researched and developed to provide the required liberation-leach data used in the ILLM approach, which is implemented online for the modelling of gold operations. The ILLM characterisation methodology, test work data analysis, interpretation and application of the ILLM test work data are discussed.CITATION:Bax, A R, McGrath, T D H, Eksteen, J J, Staunton, W, Oraby, E A, and Wardell-Johnson, G, 2016. An Integrated Liberation-leach Model and Ore Characterisation Procedure for Gold Ores, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 315–320 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By C Augustin, M Hahn, K Nienhaus

Operators of mining machinery like haul trucks or excavators have very limited information about the exact distance to other equipment as well as to the natural boundaries like berms, walls and structures such as crushers. The industry is seeking solutions to provide safety and positioning. The authors have developed a solution approach which is being used in several installations. This solution consists of three parts: first robust and compact two-dimensional (2D) radar scanners that provide range and angular information of the environment especially under difficult conditions like dust, rain, snow and fog; second an intelligent data processing framework flexible enough to adopt to different machines and operation modes like speed, inclination, visibility, tire friction, GPS position, orientation and acceleration; and third a high quality and easy to use interface giving highly condensed data to the operator, not blinding the operator at night and being sunlight readable. The truth of present proximity detection sensors is that they not only have a high false alarm rate but furthermore cover only a fraction of the possible scenarios. This makes them unsuitable for stand-alone collision avoidance systems. On the other side, mine dispatch systems only deliver database and GPS information, but no information regarding the real environment. The indurad company and its Australian partner CTS (http://www.cts.com.au) addressed these aspects by developing smart productivity enhancement driver assistance tools like lane and crusher dumping assistance.An innovative driver assistance tool developed in cooperation with the coal shearer manufacturer Eickhoff and the RWTH Aachen University has been awarded with the annual research award of its customer RAG, being the largest German hard coal producer, as well as with the bauma Innovation Award in 2010.

Sep 26, 2011

By I Gipps

A vision of what the future mine involves all aspects of mining, ie orebody access, ore stoping, material transport, processing and waste material disposal. This paper examines one aspect of the future mine: rock extraction, stoping, automated for remote operation, high productivity and low cost. Concepts for the future require a re-think of the mining process and ROES® re-examines how bulk stoping of ore can be undertaken and how this should be redesigned to accommodate the possibilities that exists with remote control and automated operations.ROES® is a new mining system for underground mines and quarries utilising a shaft located close to or within the stope for the ore breakage process. The system is designed to exclude personnel from contact with production drilling, explosive placement and detonation so all of these tasks are remotely controlled or automated. Survey of the shaft, stope back and broken rock within the stope will occur, following each blast, by remote control or automated techniques. The survey will include excavation geometry, rock fragmentation, geotechnical characterisation and estimation of ore grade. Blastholes will be surveyed before placement of explosives and, with the survey data, the optimal explosive placement and blast timing will be determined with the best available information.ROES® is designed for application in open stoping or sublevel caving in disseminated, geologically defined, thick tabular or narrow vein ore bodies. Technologies developed for ROES® will also have potential applications to caving operations, reducing the risk of frozen ore and poor fragmentation. In a typical sublevel open stope application, ROES® will reduce the stope associated development by half and will allow ore to be brought on-stream sooner and at lower cost. Other savings will flow with the centralisation of mining activities and operational data, reduction in mining fleet, reduction in ventilation requirements, improved occupational safety and reduced mine complexity.

Nov 22, 2011

By H Wang, D Wang

Mine dust is the most serious occupation hazard in coalmines. And many coal workers suffer from pneumoconiosis because of long-term inhalation of respirable dust. Reducing the dust concentration of workplaces by effective technical means is an important way to prevent coal worker’s pneumoconiosis (CWP). In order to overcome deficiencies in existing dust control technology for underground mining, especially the disadvantage of water spray technology mounted on roadheaders or continuous miners, the authors developed an integrated dust suppression technology utilising foam for fully mechanised heading faces. This paper presents an overview of the principles, materials, equipment and application of this technology. Among these, a jet type foaming device and a green foaming agent were developed, which can realise the goal of efficient preparation of foam. In addition, an arc fan nozzle used for foam spraying was invented, which can effectively cover and enwrap the dust produced by the roadheader at the cutting point and achieve the goal of efficient utilisation of foam. This dust suppression application of the proposed foam technology was investigated on fully mechanised heading faces. The results show that the dust concentration was cut down significantly with a dust suppression efficiency of greater than 85 per cent, an increase of over 30 percentage points compared to the water spray system. This study demonstrates that this foam technology can play an important role in dust suppression on fully mechanised heading faces, which provides an important method to improve the working environment and protect coal workers’ health.CITATION:Wang, D and Wang, H, 2015. Technology of dust suppression by foam for fully mechanised heading face, in Proceedings The Australian Mine Ventilation Conference, pp 177–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By D Suppel, Y Miezitis, S Jaireth

The competition between various options for the use of land is ever increasing. Commonly in Australia large tracts of land were un-encumbered by sweeping land use option limitations, but this situation has been rapidly altering in recent decades as governments are obliged to maximise the utility of the land for a broad range of competing interests. While the interests of miners have always been considered, the effects on limiting access to land for exploration and possible mining have not always been effectively incorporated into decision-making processes. As a result the challenge for national and state organisations representing these interests has been to develop a transparent process to allow for the mineral potential of an area to be systematically assessed and for information to be presented for use by specialists and non-specialists. Government agencies are called upon to implement government policy but also to provide accurate and meaningful advice which can assist in policy and land use decisions. Commonly timeframes are short and information can be less than complete. Nevertheless on-going decisions are made based upon the best available understanding. It is in this operational framework that the methods described in this paper are set. The paper describes a process for quickly and systematically providing advice on mineral potential for use by government agencies and ultimately the community within tight time and resource constraints. It is a method of combining the accumulated knowledge about mineral resources and their potential and presenting this information in an easily accessible form which can be used in a negotiation and policy development environment. Development of the method was undertaken to meet the needs of the Regional Forestry Agreement process in Australia. The method has been applied to study areas in New South Wales, Tasmania, Western Australia and elsewhere. Examples in this paper are taken from north eastern New South Wales.

Jan 1, 1999

By A Grice

AMC has completed a number of backfill options studies, including several in recent years for large, three-dimensional orebodies involving total extraction by longhole open stoping with backfill. This has led to the development of a thorough review methodology that assists in the selection of the most appropriate backfill system and the most economic mixes to achieve the required performance. A recently developed design tool has simplified the calculation of backfill strengths for various exposure dimensions and automatically determines strengths incrementally over the height of a stope. Using a generic orebody with a plan dimension of 120 m wide by 360 m long, several different stoping layouts have been analysed to determine the effect of stope dimensions and sequencing on backfill strength requirements. This has been done for stope heights from 50 m to 300 m, in 50 m increments. The required strengths have been calculated in slices and summarised for each stope in four equal layers. The average strength requirement for each layout at each stope height has been compared graphically. For all stope heights, a panel stope layout that minimises the proportion of primary stopes results in a lower average strength requirement than grid layouts on a checkerboard pattern. However, for very high stopes, smaller plan dimensions become more economic. The increase in required strength with stope height is non-linear, making taller stopes potentially more attractive. The main cost factor in most backfills is the rate of binder addition, which is closely related to the strength required. By choosing a layout that minimises the backfill strength requirement, significant savings in binder addition rates and overall costs can be achieved. These must, of course, be weighed against other factors to determine the optimum stoping layout and backfill system.

Jan 1, 2000

By M R. Lane, M L. Cramer, N P. Wines

Increasing attention is being focused by regulators and industry on the residual environmental liabilities associated with mining projects following site relinquishment (termed surrender in Queensland). Even sites that have been rehabilitated to a high standard and to the satisfaction of the regulator are not completely risk free and may require some degree of ongoing management. As well as ongoing monitoring and maintenance costs, considerations should include how costs associated with potential risk event occurrence can be quantified and, if considered material, how provisioning should be undertaken to minimise the risk to the state and to taxpayers. In Queensland for example, once a resource site is fully rehabilitated and meets its environmental authority conditions or rehabilitation completion criteria, the tenure and environmental authority can be surrendered. During the surrender process any ‘residual risks’ resulting from the use of the site for the resource activity must be considered, and, if requested, a payment given to the government to cover any ongoing management and risk costs. Accent Environmental, in conjunction with Lane Associates, was engaged by the Queensland Government as part of the government’s financial assurance framework reforms to develop an innovative, ‘one-size fits most’ Residual Risk Calculator for the Queensland resources industry. The calculator is an Excel-based tool that uses detailed user inputs to estimate post-surrender management requirements and liability at resource sites. If residual environmental risks associated with rehabilitated mine sites can be identified, quantified and managed through pragmatic regulatory tools and effective provisioning, site relinquishment/surrender can be achieved without compromising environmental and social outcomes or exposing the state to unreasonable financial risk. The effective management of residual risk can also help facilitate operations as well as relinquishment/surrender of sites where a ‘walkaway’ solution may not be otherwise technically feasible.

Aug 2, 2023

Completion of a project requires two separate money-focused activities, namely economic evaluation of the cash flows underlying the project (before financing) and if the economics look promising, how it can be financed. Economic evaluation might be best led by a person with a technical-operating background, whereas financing might be best led by an accountant. Both should be presented in simple language with easy to understand models. Economic evaluation has a sad and bad history because it evolved from the fringes of accounting. Anyone can become a self-appointed practitioner. Some still take pride in mathematical complexity without realising that they distance themselves from the decision-makers and alienate other team members. Today there is no evaluation modelling consistency across the mining industry and this reflects poorly on our discipline. It is not tolerated amongst our peers in engineering and accounting. In 2009 æbest practiceÆ economic evaluation modelling is well defined. It is:easy to follow;tailored to its purpose;transparent;discipline, rigour and consistency;recording of all source data; and hencequick to audit. Mantra: If you cannot readily understand my model you do not have a problem, I do! The task of the economic model is to make the range of business cases underlying the decision easy to understand. Intellectual power is used to simplify the decision to its key issues and risks and to present the full range of possible business outcomes in readily understood terms. Project team members, management and the board must be able to make their decisions with æeyes wide openÆ. A steering committee should be established to develop a set of standards and practices that could be adopted for economic modelling within the industry. The industry needs to purge itself of the undisciplined economic evaluation modelling that now characterises the discipline.

Jan 1, 2009

By D Sinclair

Sustainability will become a more stringent issue in mine planning over the next 40 years. The evidence of this is apparent in State and Commonwealth government policies now emerging in respect to water, green house gases, waste and other process emissions. The mining industry has developed policies such as æEnduring ValueÆ, which go some way towards establishing a framework within which mining can continue to be an underpinning strength within the Australian economy. However, the demands of new policies are directed at extending sustainability in ways that will change the way in which projects are implemented. This paper examines the nature of new policies aimed at water, energy and emissions, considering examples of where mining practices have or may change in order to meet new objectives in resource efficiency. Important issues will, as always, be the international price competitiveness of the mineral resources being produced but, where this is now devolved around mining and processing costs, these costs may in the future be strongly correlated to the nature and cost of local energy resources compared with those in Australia, the ability to mitigate and minimise water resource use and environmental impacts deriving from emissions and the veracity of competitor nations in meeting the same standards of performance in resource efficiency usage and in emissions control. As these systems bed down internationally mining in Australia will need to concentrate, amongst other things, on finding higher grade orebodies and on better technologies to release the value of lower grade ores. For our mining industry to remain strong, greater expenditure will need to be focused on these objectives. Finally, it will be important for the industry to remain vigilant and proactive in directing government policy development to ensure that practical objectives in mining are not curtailed unnecessarily through ignorance of mining market precepts developed over the centuries of mining operations.

Jan 1, 2008

New South Wales mining legislation reinforces a systematic approach to safety management. It is now a requirement of all mines in the coal, metalliferous and quarrying sectors in NSW to prepare a Mine Safety Management Plan. The paper briefly outlines work currently being undertaken by the Safety Operations Branch of the NSW Department of Mineral Resources (DMR). The DMR is working proactively with NSW mines in the preparation and implementation of effective Mine Safety Management Plans. There is a growing realisation that a systematic approach to safety management, underpinned by the process of hazard identification, has real potential to improve safety in the workplace. The paper briefly describes the framework used in a current æmines education programÆ and its æduty of careÆ foundation. Particular attention is paid to the role of mining operators in the implementation of Mine Safety Management Plans and their expected behaviour in demonstrating compliance. One challenge is convincing some mining operators that they must adopt new ways of working. Safety Operations officers are often reminded of the need to translate Mine Safety Management Plans into practical safety systems during audits and inspections of mines and through investigations into accidents and incidents. To have a real effect on the mineÆs safety performance, using these systems must be a normal way of going about a dayÆs work for all persons who work at the mine: not a safety manual collecting dust on the mine managerÆs bookshelf. Mine Safety Management Plans are important to mining operators. Not only will positive involvement in the development and use of safety systems ensure they meet their obligations under mining legislation, but it will also help prevent themselves or their workmates being injured or killed.

Jan 1, 2002

The recent trend of installing flotation cells with volumes as large as 200 m3 in concentrators is driven mainly by economic considerations such as lower capital, operating and maintenance costs. Despite the economic advantages, the metallurgical benefits from these large cells have not yet been fully realised by the industry. This is mainly due to the lack of understanding of cell operation, viz cell mixing and hydrodynamics, gas dispersion and froth transportation behaviour in large cells. There is still no rational basis for selecting optimum cell operating conditions and down-the-bank operating profiles. The relationship between cell operating conditions and metallurgy is not well established. This has resulted in poor utilisation of cell capacity in many operations. The present trend of installation of fewer cells in a bank requires each cell to be operated very efficiently. Optimisation of cell operation provides an opportunity for significant metallurgical improvements in a flotation circuit with minimal capital expenditure. Extensive work on optimising of cell performance has been carried out at various Teck Cominco operations in Canada, Peru and USA. Three different levels were involved in this work. The first level was aimed at identification of cell operating conditions for optimum mixing and hydrodynamics, gas dispersion, entrainment and froth flow behaviour in individual cells. The objective of the second level was to identify the optimum bank operating profile for cells down the bank in a circuit. The third level then focused on controlling these cell operating conditions and bank operating profiles for tighter control of concentrate grade and recovery for optimum bank metallurgy. This paper presents some of the major findings at all three levels and demonstrates the importance of each level in optimising the performance of flotation banks installed with large cells.

Jan 1, 2005

By J G. Petrie, H von Blottnitz

The selection and design of process options to deliver outcomes consistent with sustainable development requires simultaneous consideration of multiple objectives, within a climate of uncertainty û including the environmental and social aspects of technology management in addition to the technical and economic aspects of such. An issue of particular relevance in primary metal production is the deportment of minor and trace components within orebodies, products and wastes and the implications of such deportment for eco-efficiency û in particular, the long-term environmental impact of solid waste management practices. The identification of opportunities to enhance recovery of valuable by-products and simultaneously improve the environmental acceptability of final waste output requires a clear understanding of the distribution of the relevant ore components, which results from the choice of processing route and unit operation efficiency. This is challenging, given that process streams generated during primary metal production are generally poorly characterised and the behaviour and deportment of trace to minor and trace components is not well understood. This paper demonstrates how current data gaps and inconsistencies can be systematically addressed through the meaningful reconciliation of empirical plant data with a fundamental understanding of the mechanisms and parameters influencing element behaviour and deportment during the formation and subsequent beneficiation of mineral ore deposits. On this basis, quantitative distribution data and a comprehensive and comprehensible inventory of unit process inputs and outputs as a function of ore compositions and processing technology options can be generated, which is consistent with early design stage information requirements, both in terms of detail and accuracy, ie is æfirst-orderÆ in nature. This predictive approach to element distribution during primary metal production provides decision-makers with key information in the early design stages of a project (in terms of developing processes within the context of sustainability), whilst simultaneously guiding further data collection and environmental impact prediction studies.

Jan 1, 2006

By Ketelaar P. B, Nichols S, Power W. L, Utley D. C

The impact computers are having in geoscience is distinctly mixed. In the petroleum industry where much of the data are based on geophysics, computers have become an integral part of exploration and reservoir evaluation and simulation. In the minerals industry, the trend to computerisation is more advanced in some disciplines than others. Geophysical and remote sensing data are routinely processed and imaged using state of the art computer techniques. Mine surveying, planning, design and resource and ore reserve estimation are now all predominantly reliant on computers. However senior management of many companies, particularly in the mineral exploration industry, are still reticent to fully embrace the technology. 3D computer modelling of geology and orebody delineation is still largely in its infancy. Two current and significant drawbacks to the routine use of computer modelling of geology in both mining and exploration are the tedious and time consuming modelling process and the lack of seamless interaction between 3D computer-aided drafting (CAD) software and geographical information systems (GIS) which are largely 2D in their data treatment. There is an urgent need for a 3D spatial information system (eg 3D GIS) with intelligent and rapid modelling functionality. One of the keys to the successful building of 3D geological computer models begins with data base structure and design to ensure that there is no loss of data fidelity through data capture, storage, manipulation and modelling. Once a model is constructed, the latest generations of visualisation software provide sophisticated environments over a range of hardware platforms for visualisation in both mono and stereo viewing. This is demonstrated by the geological models which are presented in the digital interactive version of this talk whose URL on the World Wide Web is: http://www.ned.dem.csiro.au/FRACTAL/pubs/talk97AUSIMM/

Jan 1, 1997

This is a welcome opportunity to exchange ideas about educating for a profession in mining and metallurgy, and I shall use it to highlight the ways in which educators, the industry, and the profession can help one another make that educa- tion better. This is home ground for me in more ways than one. As the executive head of a uni- versity perhaps I may speak as an educator; and there is still, I hope, enough of the metallurgist in me to allow me to speak of what we metal- lurgists and mining engineers can do to help the educators. Another interest should be declared, too. Among the educating agencies I shall focus on universities; among universities I shall further focus on my own, the University of New South Wales. I know it best; and, more to the point, we are one of the minority that offer a full profes- sional training in mining and metallurgy. Further, we are as a university very much concerned- more than most-with specifically professional education, and especially with education in the professions based on science and technology. Mining and metallurgy have of course played a central role, from earliest times onwards, in the history and development of science and tech- nology. In that role they have been both pro- ducers and consumers of new knowledge. Indeed the whole new attitude to knowledge that began to spread in 16th and 17th century Europe owed a great deal to the interests and traditions of the miner and the metallurgist. The first modern text- book of mining and metallurgy, George Agricola's De Re Metallica, is very much more than a spec- ialist handbook; it is a major landmark in intel- lectual and cultural history.

Jan 1, 1978

By P F. Knights

Mining companies are striving to achieve new levels of operational maturity and drive process improvement across the organisation in the face of unprecedented demand and limited supply of experienced human resources. Advanced analytics techniques can help overcome these fundamental challenges by applying data techniques not previously applied in mining. Today, decisions are usually locally optimised but do not achieve optimum capability for the value chain. Although more information is collected then ever before, it is difficult to link many sources of data together in the same place in real-time, for example plant history, maintenance, mine planning, logistics and engineering data. Consequently complex analysis of data is time consuming and requires specialist skills and knowledge, and is often neglected in the decision-making process. In the future, analytics will close the loop between analysing data and taking action. Analytics will become embedded in the business and routinely applied to improve decision making across the organisation, from senior management to operations and maintenance workers, but will not require specialist skills or be time consuming to analyse data. As analytics becomes embedded in the business process, decisions are supported by data (not on gut feel), and critically, data from many sources are integrated in real-time to improve the quality of decisions. Ultimately, predictive tools will help suggest, or even in some cases automate, courses of action. The main opportunities for analytics exist where the enterprise requires supporting technology to enable it to continue to evolve to higher level of maturity. This will be in the areas of asset management, rapid reconciliation and adaptive planning, and the inbound and outbound supply chains. Advanced analytics are also a key enabler for increasing the effectiveness and realising the true value of Remote Operations Centres to safely and efficiently support operations in remote locations with smaller workforces.

Jan 1, 2008

This work was instituted to investigate the microscopic structure of brown coals by means of microtome sections cut from them. It was found to be essential to impregnate the coal with some material prior to cutting, because of its powdery and crumbly nature. Of a number of impregnating materials tried, e.g., glycerine gum, gelatine, by far the most satisfactory was paraffin wax. Samples of brown coals for section cutting must be moist. When obtained, they should be put immediately into air-tight tins, and, if they are not to be used for some time, it is desirable to keep them under water containing a small amount of formalin. If the sample is allowed to dry in air, it becomes too hard to be cut. It cannot be softened again even by prolonged soaking in water.PREPARATION OF COALSmall rectangular, blocks were cut from the sample with a chisel and a strong scalpel. The largest block prepared was 3·2 x 2·5 x 0·6 cm. The faces of the block from which sections were to be cut were approximately levelled before treatment. The block was then painted carefully on all sides with two coats of warm aqueous agar, approximately 2 %. This prevented crumbling and breakage of the block during treatment. When the agar was set, the block was placed in water, and all the air removed with a vacuum pump. The water was replaced first by alcohol, then by chloroform, by the usual step transference of a series of liquids, in each of which the block was placed for 24 hours: Ethanol %, 10, 20, 30, 50, 70, 85, 95, 100 (three changes); Ethanol-chloroform, 3: 1, 1: 1, 1 : 3, chloroform pure (three changes) '. The blocks were then embedded in paraffin of melting point 56-58°C. Fresh...

Jan 1, 1947

The approach to this subject is a very general one, but an attempt has been made to cover briefly a very wide field in the nationally important job of manufacturing iron for the iron and steel industry.Some historical data concerning the development of the furnace itself from early days have been followed by the modern ideas on raw materials and their beneficiation. Recent furnace design and modern auxiliaries have been given attention with, finally, some developments in practical operation.HISTORICALWhen dealing with such large 'and costly operating units as blast furnaces, there is not the same opportunity for research in design as in most other metallurgical processes. Over past generations the development of furnace design, or "lines" as it is usually termed, as well as most radical operating changes, has been very gradual.However, there have been some periods of rapid progress due to revolutionary changes. One such was the adoption of the steam engine for blowing and charging operations, and also, during this same era, about 1750, coke was first used as fuel in place of charcoal. Another revolutionary change came some 100 years later, when heating the blast became usual practice.Since then there have been great improvements in mechanical equipment and in the preparation of raw .materials. These factors, together with a better understanding of what happens inside the furnace, have led to the development of those large mechanically operated structures which are the most modern in blast furnace design.For many, years America has led the world in pig iron production and in furnace development, so that American design and practice is now recognised almost as standard. This type of furnace replaced the older stacks in England, Russia, Germany, South Africa and India, as well as here in Australia.

Jan 1, 1947

Coal losses and dilution are among a coal mine operators everyday problems. These losses and unwelcome additions are generated primar- ily by the stripping operation and secondly by the coal mining opera- tion. Losses in yield due to preparation plant efficiency are a separate issue although they may be related to the coal mining operation. The losses and dilution can be traced to the following operations: (A) Overburden or Interburden Removal (1) Removal of coal edge by blasting operations. (2) Removal of top of seam by drilling/blasting. (3) Removal of top of seam by stripping equipment. (4) Removal of coal edges by stripping equipment. (5) Dilution due to stripping equipment. (B) Coal Mining (for the case where seams are ripped rather than shot) (1) Coal rib losses. (2) Coal rib dilution. (3) Coal left in floor. (4) Coal left in fault areas. (5) Floor material picked up whilst loading. (6) Spoil material picked up. (7) Spoil material from poor surface clean up. (8) Top of coal losses from final clean up. (9) Dilution from ripping too deep, i.e. into floor below seam. (10) Dilution from interseam parting. The losses apply to both the single seam and multi seam oper- ations although they are more pronounced in the multi seam mines than in a single seam mine due to the position of the coal which is lost. For example in the multi seam case the top seam coal edge loss is final. There is little chance of recovery with the subsequent pass even if the extra rehandle is done. However conversely the lower seam is relatively easy to locate as it has nowhere to go being contained by the lowwall bench.

Jan 1, 1988

Many persons hold the opinion that the metal indus- ries are fortuitous and that the occupation is one of sordid toil, and altogether a kind of business requir- ing not so much skill as labour. But as for myself, when I reflect carefully upon its special points one by one, it appears to be far otherwise. So wrote Georgius Agricola in 1556. He could have been espousing the sentiments of an indus- trial archaeologist investigating mining sites in 1986. South Australia has a very rich legacy from its industrial past-especially in the area of its mining history. Industrial archaeology, which is part of the broad field of archaeology, is concerned with the material and documentary remains of this industrial past. This includes the products and processes of manufacturing, industrial, technolog- ical and engineering activity and their relation- ships to people and the environment. `Archaeology' immediately conjures up the image of excavations in Greece or Eygpt. Excavation however is only a part of archaeological methodology. Industrial archaeology utilizes documentary historical rec- ords combined with field survey techniques (both above and below ground) to create a composite picture of the past. Interest in our recent past has burgeoned in Australia in the last few years. This interest manifests itself in many ways-the unprecedented popularity of Australiana and col- lecting, the plethora of Australian historic films, the growth of the National Trust, local historical societies and genealogical research. Fortunately these trends have been reflected in academic and legislative circles. Various univers- ities, institutes of technology and colleges of advanced education run courses in aspects of cul- tural resource management and conservation of the historic environment. These courses are com- prised of archaeology, architecture, geography, his- tory, materials conservation, museum studies, and national parks management and planning.

Jan 1, 1987

This paper describes operational experience with seam gas and spontaneous combustion management, gained during ten years of production history (1993 to 2003) in the Wynn seam at Dartbrook Coal mine. In addition, comparisons are made with more recent operational experience in the overlying Kayuga seam. Development and retreat longwall operations were undertaken in a 4.0 m thick working section of the Wynn seam, contained within the lower quarter of a circa 24 m thick mega seam, from 1993 until mining operations were relocated to the overlying Kayuga seam in 2004. Production from the first block of the Kayuga seam is currently underway with seam gas and spontaneous combustion management requirements being refined as further operational experience is gained. Seam gas management techniques, including pre-drainage with pressurised fracturing, surface to underground goaf drainage of a carbon dioxide rich seam gas and novel, high capacity ventilation circuits, were employed in the Wynn seam. Ventilation strategies included operating up to carbon dioxide STEL concentrations of 3.0 per cent in segregated return airways rather than being limited to the TWA-TLV concentration of 1.25 per cent. The spontaneous combustion experience at Dartbrook Coal has, to some degree, resulted in a change in the way the risk is managed in Australian coal mines. Values of carbon monoxide make and hydrogen concentrations are profoundly different from previously recommended management plan trigger levels and those used elsewhere in the industry. However, the detection of higher hydrocarbons together with rising oxygen depletion ratios and absolute hydrogen concentrations remain as indicators of advancing spontaneous combustion events. In this respect, experience gained in the Wynn seam was important in the initial management of the shallower Kayuga seam, an essentially greenfield site with no prior operational experience being available.

Jan 1, 2005