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Australian contract mining as it is known today had its origins in the early-1980s. Before this time there were numerous examples of underground mine development, and specifically shaft sinking being carried out by contractors. However, these were typically international contracting companies who came to Australia for specific projects. Growth in the underground mining industry in the 1980s opened up the opportunity for contractors. Mine owners had a need for contractors who could bring technical and operational capabilities to a project combined with capital in the form of equipment. In the early years the contracting industry was dominated by smaller players who focussed on mine development. The relationship between mine owner and contractor was loose and typically contract documents were rarely referred to. Through the 1980s and 1990s the underground contracting industry in Australia grew to where today there are over 20 underground contracting companies operating in an industry with an estimated annual value in excess of $1 billion. Of these 20 companies approximately five dominate with annual turnovers exceeding $100 million. Underground contractors now provide all facets of underground mining including development and production. Over the last 20 years the underground contracting industry has been able to consistently lower costs to mine owners through a combination of:equipment productivity, labour productivity, and technical innovation.

Jan 1, 2002

The grades of alluvial ore deposits are low compared with grades of hard rock mining. This factor, combined with other parameters of irregular distribution of particles, bedrock irregularities, size of particles, nugget effect, ore characteristics, and wet horizons, combine to place alluvial deposits among the most difficult to evaluate, and on which to establish an ore reserve with a high degree of confidence. With increased geological input, correct selection and implementation of sampling method, due regard to sample representativity and process design, these confidence levels can be achieved.

Jan 1, 1987

With the introduction of the Health and Safety in Employment (HSE) Act 1992 and the subsequent repeal of regulations pertaining to mining, there has been an upheaval of the management of health and safety in mines.  More than ever, employers know that they must ensure that their workers are competent to carry out their assigned tasks.

Jan 1, 1997

Sustainable development places a heavy burden upon everyone involved in the public policy debate, about how to balance economic growth and environmental protection. We must treat that responsibility very seriously indeed. The mining industry especially cannot dodge the responsibility, even if it wished to.

Jan 1, 1992

The recommendations of a recent American report on "Better contracting for Underground Construction" are considered in relation to Contracting practices on major Australian projects by representatives Of the "classical trilogy" - the Owner, Engineer and Contractor.

Jan 1, 1976

Basic premises for evaluating special characteristics of gold-bearing porphyry metal systems stem from their contrasts with properties of the class as a whole. Included features are differences in geologic, thus tectonic, environments, subtle but real differences in the proportions of accessory metals Mo-Ag-Au that are regionally and within some regions, tempo-rally distinct, contrasts in the Ag:Au ratios, petrological-geo-chemical as well as isotopic differences between intrusive suites, the age and nature of host terranes, contrasts in alter-ation style, and zoning variations of mineralogical and physical properties of rocks. These properties are linked in various ways in different regions and suggest that in large gold-bearing systems where gold may be uniformly distributed, environ-ments of emplacement, and compositions or sources of igneous "progenitors" may dominate in importance over processes, and that systems in which gold is zoned are processes-dominant.

Jan 1, 1990

By Markic S, Subelj A

Long-term plan for lignite mine Velenje has been made by using technical parametrisation method where the basis for periodical, middle- term and short-term plans as well as for scheduling has been already fixed. For a certain time period a plan

Jan 1, 1998

Fluid bed sulphation roasting followed by leaching at low pH was developed as a means of separating copper and bismuth from a mix- ture of flotation concentrates and flash fur- nace flue dust. A 65 tonne/day plant was established and typically achieves 89 percent copper extraction with negligible bismuth and iron extraction. Acid-chloride leaching of bismuth from copper leach residue was then established, with bismuth oxychloride being precipitated from solution by dilution with water. A small scale batch plant presently in operation typic- ally achieves 80 percent recovery of bismuth to bismuth oxychloride.

Jan 1, 1986

By S Cossfo Torres

Minera PenmontÆs gold mine, La Herradura, is located at the northwestern Mexican state of Sonora and consists of an open pit mine and heap leaching facility for the recovery of gold. The production began in July 1998, and today La Herradura produces about 200 000 oz of gold per year. Standard sampling and assaying protocols were established during exploration based on heterogeneity tests. However, at deeper zones of the pit, coarse gold became evident and it was necessary to develop a new sampling protocol in order to minimise the fundamental error and improve the metallurgical accounting. This new sampling protocol requires cyanide leaching the whole pulverised sample from the blasthole, assaying pregnant solution and fire assaying 50 g of tailings. A sampling study was performed on 195 blasthole samples analysing gold under the standard and new protocols. The new protocol demonstrated that the original one underestimated gold grade by approximately 27 per cent, with impacts on ore misclassification and metallurgical accounting. According to the ore grade control system, mineral with gold grade above 0.35 g/t was sent to the leach pad and mineral with lower grade was classified as waste. Based on the sampling study, it was decided to classify a low-grade ore with gold assay between 0.20 and 0.35 g/t which was stored for future treatment under better gold prices or should mine production decrease. These two conditions were present during 2005 and 2006, when about 3.5 Mt of low-grade ore were leached.

Jan 1, 2008

By J Demchak, L M. McDonald

The duration of acid mine drainage flowing out of underground mines is important in the design of watershed restoration and abandoned mine land reclamation projects. People conducting land reclamation projects usually employ remediation strategies once (reshaping land, revegetating soils, and installing water treatment) with the hope that these methods will adequately improve water quality for a long time, with little planning for future changes. An understanding of changing acid water conditions from underground mines over time will help in designing efficient and cost-effective treatment methods. Past studies have reported that acid water flows from underground mines for hundreds of years with little change, while others state that poor drainage quality may last only 20 to 40 years. Several factors are important in making a prediction of drainage quality over time, such as inundation or flooding history, coal seam characteristics (primarily sulfur content), residence time of water in the mine, time since mine closure, mining method and amount of coal remaining, collapse of roof and other disturbances within the mine, and subsequent nearby surface mining. More than 150 above-drainage (those not flooded after abandonment) underground mine discharges were located and sampled during 1968 in northern West Virginia, and we revisited 44 of those sites in 2000 and measured water flow, pH, acidity, alkalinity, Fe, Al, and sulfate. All 44 discharges were from mines in the Pittsburgh and Upper Freeport coal seams, and both seams have been extensively mined in this area during the past 70 years. We sampled during the same months (June to October) as were sampled in 1968, and we found no significant difference in flows between 1968 and 2000. Therefore, we felt that the water quality data could be compared and that the data represented real changes in pollutant concentrations. There were significant water quality differences between year and coal seam, but no differences between disturbed and undisturbed mines. Average acidity declined 79 per cent between 1968 and 2000 in Pittsburgh mines (from 3342 to 702 mg/L), and 56 per cent in Upper Freeport mines (from 1189 to 519 mg/L). Iron decreased an average of about 80 per cent across all sites (from an average of 345 to 69 mg/L), while sulfate decreased between 50 to 75 per cent. Pittsburgh seam discharge water was much worse in 1968 than Upper Freeport seam water. Twenty of our 44 sites had water quality information during 1980, which served as a midpoint to assess the slope of the decline in acidity and metal concentrations. Almost all parameters showed an exponential rate of decline in acidity, iron, and sulfate.

Jan 1, 2003

Alaska Native corporations, as representatives of the aboriginal inhabitants of Alaska, control the mineral rights to 18 million hectares of Alaska, approximately 12% of the state. These corporations were established through legislation passed by the United States Congress in 1971 designed to settle the land claims of the Native peoples of Alaska. Twelve corporations, each representative of a specific geographic and cultural region, were established and granted the mineral rights to most Native lands in their respective regions. Since that time the Native corporations have taken an active role in mineral development in the state. Generally through agreements with established mining companies, Native corporations encourage balanced exploration and development of their lands. Substantial mineral potential has been recognized on Native corporation land, which includes holdings in many historic mining districts of Alaska. Several world class deposits have been discovered on Native corporation land, including the Red Dog zinc-lead deposit, which began production in late 1989. The experience of Alaska Native corporations demonstrates that aboriginal peoples can be very positive forces in resource development.Alaska, although remotely located in the Northeast corner of the Pacific Basin, is playing an increasing role as a supplier of natural resources to the region and the world. Most of Alaska's privately held natural resources are owned by the aboriginal inhabitants of the state. These aboriginal inhabitants, now collectively referred to as Alaska Natives, have emerged in the last two decades as having a major international impact in mineral resource exploration, development, and production.

Jan 1, 1990

By Braes J. R, Neale J. R

The New Broken Hill Consolidated Limited (NBHC) mine currently produces 1.42 million tonnes of silver, lead and zinc ore annually. All of this ore is treated by the NBHC milling ccx[plex. This paper describes the crushing, grinding, flotation and filtration circuits used in the treatment of this ore and lists the major items of equignent used in these circuits. Metallurgical results, manning levels and consumption rates of reagents and grinding media are shown.

Jan 1, 1983

It is people, not organisations, that make countries great, so it seems appropriate in this Centenary year of The Australasian Institute of Mining and Metallurgy to highlight some of the mining personalities who have contributed to the greatest and most important of Australia's export industries, the Resource Industry.

Jan 1, 1993

This paper presents the results of studying the influence of catastrophic failures arising in mines, on the behaviour of mine ventilation systems. It is very important to take account of this influence for the stable operation of the system and to ensure mine safety when mining underground coal and ore deposits.

Jan 1, 2003

In the 1890s, The Goldfields Water Supply Department in Western Australia commissioned the diamond drilling of two deep artesian exploratory water bores near Coolgardie (Blatchford, 1899). At the time, in spite of strongly-worded advice to the contrary from the Government geologists, there was a wide popular belief that you could obtain artesian groundwater virtually anywhere providing you drilled deep enough. The first Coolgardie hole was drilled to over 900 m, despite the fact that the bore penetrated granite from a depth of 5 m below the surface. Drilling proceeded for more than 16 months, between July 1896 and November 1897. A small quantity of salt water was struck at a depth of 36 m. The second bore was mercifully terminated at a depth of 50 m, also in granite, with again only a small inflow of salt water. Such were the desperate lengths that were pursued to obtain a reliable water supply for the influx of people in the Eastern Goldfields gold rush. The WA Goldfields continued to rely on huge condensers for water supply until that great engineering feat, the construction of a water pipeline from Mundaring Weir to Coolgardie, was completed in 1903. An enormous network of rail tracks penetrated outwards from Kalgoorlie and Coolgardie for the collection of timber, principally to feed the condensers. Remnants of the rail network are still visible today. The acute shortage of fresh water led to great deprivation, disease and death among the early miners. Today, the water problems faced by the mining industry are thankfully not as severe, but they are nevertheless no less challenging. The southern part of the WA Goldfields is a notoriously difficult area for finding potable quality groundwater. Even as recently as the 1990s, there were occasional serious efforts to find potable groundwater in that area, some very imaginative and innovative. One mining company, working south of Southern Cross, spent many months experimenting with recovery of potable quality water from a shallow freshwater lens overlying hypersaline water in a low permeability weathered granite aquifer. They used very low capacity pumps manufactured from car windscreen washer pumps powered by solar panels.

Jan 1, 2000

According to the analysis of 126 mine gushing records and the relevant water supply and hydrogeologic condition, the gush can be classified into eight types;cave type,collapse -column. type, subterranean stream type, fault zone type, contact zone type, upper plate type, bottom heaving type and surface water invasion type. The formulae for counting the peak discharge of gushing point are further put forward in this paper.

Jan 1, 1988

More than ten seafloor massive sulfides (SMSs), which tend to be enriched in Au and Ag with varying amounts of Zn, Pb and Ba, have been reported in Japanese Exclusive Economic Zone (EEZ) including the Jade hydrothermal field in the Izena cauldron Okinawa, theSunrise deposit in Myojin knoll Izu-Ogasawara, and other active deposits found in the past 20 years. From the fiscal year 2008 some universities in Japan will begin development of sensing devices to delineate surface distributions of known SMSs and to find new ones. The devices would be deployed by an autonomous underwater vehicle (AUV) or remotely-operated underwater vehicle (ROV) later in active hydrothermal fields and potential areas in the EEZ. On the other hand, different laboratories are planning to research and evaluate SMSs with state-of-the-art methods such as the benthic multi-coring system and geophysical devices to collect information in deeper parts of the SMSs. In this session recent projects on exploration and evaluation of SMSs with some new trials including geophysical and geological surveys in Japan will be reported. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By C Xu, B Li

Multi-sensor fusion visual perception technology significantly enhances visual perception capabilities in complex and harsh environments by combining visual data from different sensors. This technology is especially useful for scenarios where traditional single visible light sensors, such as standard cameras, struggle due to poor lighting, adverse visual conditions, or other visual obstructions. In environments with low light, smoke, or dust, the performance of conventional visible light sensors degrades, limiting their application. By integrating data from various sensors like radar, infrared thermal imaging, and others, multi-sensor fusion technology provides a more comprehensive and complementary visual solution. This fusion not only enhances the robustness of visual systems but also greatly expands their potential applications in fields like visual surveillance. In recent years, deep learning methods have become the mainstream technology for addressing multi-sensor fusion issues, demonstrating significant advantages in adaptive feature selection compared to traditional machine learning methods. However, deep learning-based multi-sensor fusion algorithms still face several challenges. The design of network structures is often redundant, lacking effective screening of useful components within multimodal information. Mainstream fusion algorithms focus excessively on improving display effects without adequately considering the needs of downstream applications and tasks. Existing fusion perception algorithms are generally designed for open visual scenes and lack targeted design for complex visual degradation factors present in tunnel environments of mines. Current deep learning methods for designing multi-sensor fusion networks heavily rely on manual experience to create fusion modules. This reliance increases the complexity of network design and can lead to redundancy. Redundant network modules are difficult to identify in end-to-end learning tasks at this stage, significantly slowing down network inference and potentially interfering with the output of fusion perception. Additionally, training these fusion modules typically requires large amounts of well-annotated multimodal data, further increasing implementation difficulty and cost. For instance, the fusion network design proposed by Li and Wu (2018) focuses on extracting multimodal fusion features, while Zhao et al (2020) introduced a feature decomposition mechanism in the feature fusion and extraction modules. Researchers like Zhang and Ma (2021), Xu et al (2020), and Liu et al (2017) have attempted to improve network structures through dense cascades and the introduction of residual connections. Although these methods have improved the handling of multimodal information to some extent, they still face limitations in distinguishing between useful and redundant information, with redundancy persisting in network designs. Ideally, the design of fusion networks should be more intelligent, guiding network structure design heuristically based on the importance of different modal information for the current task. This would reduce information redundancy and network weights, requiring the development of new algorithms or frameworks capable of automatically identifying and optimising fusion strategies, thereby reducing dependence on manual experience while improving fusion efficiency and network performance. Current deep learning designs for multi-sensor fusion algorithms often overlook the

Sep 1, 2024

Every year my consultancy business reviews over 100 mines worldwide, primarily focusing on property and business interruption risk. What we have found is that the most successful mines have: identified their principal risks and determined what controls are required to manage or eliminate these risks; and managements systems that underpin these risks and the business in general.

Jan 1, 2003

This paper provides an overview of the future for underground thick seam coal mining in Australia. It reviews the available and anticipated mining systems and technologies which may be adopted to mine coal seams of greater than 4.5 m thickness, together with an assessment of the likely technological and operational risks and challenges involved. This overview of mining systems is presented in the context of both current and recently completed research projects funded through the Australian Coal Association Research Program (ACARP). The projects have been joint investigations between The University of New South Wales Mining Research Centre (UMRC) and the Centre for Mining Technology and Equipment (CMTE). Outcomes from the projects have included an appraisal and classification of underground thick seam reserves in Australia and their suitability for each mining method.

Jan 1, 2000