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Falling asleep at the wheel of a moving vehicle is not only dangerous but avoidable. It is implicated in up to 30% of all road fatalities in general and up to 65% of mining incidents involving haulage trucks. These types of crashes normally result in serious injury and/or fatality due to the lack of breaking that occurs. However, when a 300 tonne haul truck has a sleep related crash it is not only the safety of the driver that has a high price but also the commercial impact on the mines? productivity and efficiency. We have been developing our ASTiD technology which stands for the Advisory System for Tired Drivers to seamlessly integrate in to Modular Mining?s Dispatch system to provide real-time early warning fatigue risk management. The benefits being driver shift optimisation, sustained productivity and of course less accidents. By monitoring the drivers alertness levels in real-time using ASTID, the Dispatcher becomes empowered to make critical, management decisions that will ultimately prevent serious injury or loss of life and the driver gets to stop when he needs to and not just when he is supposed to. This paper shows how this integrated solutions works.

May 1, 2011

By D. Legg

This is the first in a series of studies commissioned by the European Environment Agency that aim to raise awareness of the use of economic instruments and assess their effectiveness. The emphasis is on sharing good practice and increasing knowledge and understanding across European countries in this emerging policy area. A methodology for evaluating the effectiveness of economic instruments has been developed and this will examine whether the inclusion of economic instruments in complex policy packages can improve the overall performance, particularly as a prevention tool in terms of resource use and waste generation The focus for this initial study is the use of aggregate taxes in four EU countries which include the Czech Republic, Italy, Sweden and the UK so that a range of experiences (e.g. geographical, political etc.) can be included. The findings will be used to inform and influence future policy development in other EEA countries. The methodological approach is divided into two main sections: - Technical analysis, which covers quantitative and qualitative analysis. - Process design, i.e. who should be involved when, where and how. Process design is essential if the full learning benefits are to be gained from the technical analysis, which is the ultimate objective of these evaluations.

Jan 1, 2007

The emerging discipline of ægeometallurgyÆ is not new but is becoming increasingly recognised as a discrete and high-value activity that reflects an ongoing commercial and cultural trend towards more effective mine site integration and optimisation. The AMIRA International P843 æGeMIIIÆ project (Geometallurgical Mapping and Mine Modelling) is a major new cross discipline research collaboration designed to provide support for this emerging industry trend. The project is currently supported by 18 global mineral companies and involves collaboration between the CODES Centre of Excellence (University of Tasmania), JKMRC and BRC (University of Queensland) and CSIRO Exploration and Mining. These groups represent recognised research excellence in the fields of economic geology, automated core logging, advanced microscopy and process mineralogy, mineral processing, mine planning and resource optimisation. The needs and challenges of geometallurgy as an integrated activity will be outlined together with the ongoing contribution and aims of the AMIRA P843 æGeMIIIÆ project. The main emphasis is on development of predictive geometallurgical indices for key processing performance parameters that reflect inherent geological variability. The ultimate aim is to provide predictive indices of geometallurgical performance that can be confidently embedded into resource models and used for risk-defined mine planning and optimisation.

Jan 1, 2008

By Juan P. Camus

One of the most important decisions in mine development is the selection of the mining method. Open pit or underground methods are selected depending on the shape of the deposit, and its position with respect to the surface. When the decision is not clear or evident, then the common rule is to compare underground and open pit projects to choose the one which yields the maximum return. However, in some circumstances' the best alternative is to start-up the operation with an open pit until a point where mine operating costs make more convenient to employ an underground method. In this case, the final pit limit is not directly related with commodity prices and its position is a funtion of capital and operating costs associated with both methods. The goal of this paper is a mans of establishing the proper ultimate pit considering a potential underground mine. The methodology is quite simple and can be implemented to work with a variety of available routines for pit optimization, such as Lerchs-Grossmann, floating cone, network flow and the Lemieux moving cone optimizing algorithm, which is the tool used by the author.

Jan 1, 1992

By Sehic OA

One aim of testwork and flowsheet development is to ultimately provide a reliable and flexible plant that is simple to operate and maintain. Testwork can indicate amenability of ores to CIP treatment and provide a basis for process design and economic appraisal. Batch cyanidation and CIP tests are often sufficient for small projects. Continuous multistage test rigs can be operated to simulate plant operation and to provide data for flowsheet optimisation. Operating requirements, gold recoveries and potential problem areas can be anticipated at an early stage with more confidence. Subsequent project development involving decisions on the basic flowsheet, equipment types and general plant arrangements are based on practical considerations and experience. Computer aided process modeling and economic appraisal can be useful in analysing various tradeoffs, firming up the flowsheet and equipment sizes, and in specifying operating targets for the future CIP plant. INTRODUCTION Carbon-in-pulp (CIP) technology which has developed rapidly since 1974 is now accepted as an economically and technically viable process for the efficient recovery of gold. This paper describes testwork and flowsheet development procedures used for CIP evaluation and design.

Jan 1, 1982

By A. T. Yu

Two key components make up the core of a rapid excavation operation. They are: the breaking up of the rock and its removal. Owing to the complexity inherent in mechanical rock-breaking and the relative infancy of the art, for a number of years the first of these two components has received virtually undivided attention from the industry. Only recently has some concern been expressed about the technology and the economics of the much ignored second component: muck removal. As the continuous boring machine's percentage downtime continues to trend lower in the future, the need for adequate and more effective materials handling systems in rapid excavation will become increasingly more acute. (1) Recognition of the need for a broader and more far-sighted approach to our problem has been eloquently underscored in the conclusions of the Committee on Rapid Excavation sponsored by the National Research Council: "Ultimate attainment of the desired cost and speed improvements is significantly dependent on recognition of the excavation process as a system whose subsystems are critically inter-related. Substantial amounts of full-scale field testing of integrated driving, muck removal, and support subsystems are required." (2)

Jan 1, 1997

In attempting to vegetate pnob!em sites some basic pn.i,ne%ptes, namely the phys.ica.e and chemi.ca2 pnope/ti;es og the problem mateni.al and the selection oU hu.itab.2e p!antts {cor pnopagati.on, have to be considered. Pnobtem sites such as tai ing dams, mined-out atteas, and areas which have been genehaUy advehse2y a46eeted by mining activities, are not only o~ten located in a divehs.ity o4 climatic regions, but they also usuaUy dL64en substantially in theAjt .int' Lns c phys.ica2 and chem.i cat pnopen t i.es . To estabP.ish vegetation on such sites 6requent2y requites: .%) The ame Lonaton oU adverse {yaetors in onde t to exeate a hoot env.utonment suitable Uon "satis1actony" plant growth. .%i) These.2eationo4 plant species suited to the improved Hoot env.utonment, and eompat%b&e with the e2imate o{y the site, and the ultimate Land use o4 the site. iii) The estabL shment o{y a Laboratory and p-LLot scale testing programme to aeeomptizh the above.

Jan 1, 1976

By G. Viramontes-Gamboa

Approximately 70% of world copper reserves consist of the mineral chalcopyrite, and much international effort has focused on its study. Ultimate objectives include the development of environmentally friendly alternatives to smelting, and technologies to treat low-grade ores, for which concentration and smelting are economically unviable. Unfortunately, chalcopyrite leaching is inefficient in H2S04-Fe2(S04)3-FeS04 solutions, which is considered to be the most desirable oxidizing medium for leaching of copper sulfides, since the chemistry is well known, corrosion of industrial equipment is negligible, subsequent copper recovery by SXlEW is well established, and environmental impact is minimal. The main reason for this inefficiency is the self-passivation of chalcopyrite. We have devoted considerable effort in the understanding of this phenomenon, and have developed a predictive electrochemical methodology capable of establishing a priori the precise range of potentials within which chalcopyrite leaches and where it is passivated. Since potential control is a critical parameter in chalcopyrite leaching, this experimental methodology can be very useful for establishing the best conditions to leach chalcopyrite. In this paper, the scientific foundations of this predictive experimental technique are presented, and its practical application is demonstrated by comparing its predictions with leaching experiments from the literature.

Jan 1, 2007

By K. Rama Sarma

Piles are frequently subjected to lateral forces and moments in addition to vertical forces and hence the piles have to be designed for both lateral loads as well as vertical loads. In the design of such pile foundations, two criterias must be satisfied. First an adequate factor of safety against ultimate failure and second, as acceptable deflection at working loads. In this study the work has been carriedout to study the lateral deflection pattern of the pile. The solutions to the problem primarily depend on soil modulus. Equations for computing the values of slope, deflection and coefficients for many types of soil conditions have been developed for static loading for long piles. As analysis part is not available for the above methods for the values of depth coefficients in the tables. It is required to go for linear interpolation which is not valid and highly unreliable. In this present method, coefficients can be obtained for any value of depth coefficient (z) with simple calculation. The present method is very concise and allows one to ana­lyse any type of pile with varying depth coefficient (z) even without the availability of any practical data regarding applied lateral load (P1) and moment (M1).

Jan 1, 1996

By James E. Monsees, Richard J. Proctor

INTRODUCTION Los Angeles is one of the world's largest cities in area with a span of 70 km between its north and south limits. The population in the Los Angeles Basin exceeds 11 million people. Los Angeles is second only to New York City in density of U.S. urban population and it operates one of the largest city bus fleets in the world, 2,500 buses. After many years of planning and many consultants' reports, it is planned to initiate a 30 km (18.5 miles) starter line subway -- the "Wilshire Corridor" (Figure 1). Construction is to start in 1985. In several locations, subway routes ultimately will skirt or cross old oil fields, which may cause gassy tunneling. Of particular note are the La Brea Tar Pits, which overlie a part of the old Salt Lake oil field. Tunneling through tar sands for about 3 km will be unique for subway construction and will occur on the starter line. Experience with previous gassy tunnels in the greater Los Angeles area shows that tunnels can be completed safely if precautions are taken. Abundant ventilation is the main solution, although other precautions are discussed herein.

Jan 1, 1985

By W. A. Selvig

"INTRODUCTION In 1942, Lowry and Junge 3/ reported the results of a statistical study of errors for the proximate and ultimate analysis of coal and coke when made according to the standard Methods of Laboratory Sampling and Analysis of Coal and Coke (D271-42) 4/ of the American Society for Testing Materials. Some of the laboratories that cooperated in the investigation reported difficulty with determination of the volatile matter of anthracite and low-temperature coke. The small number of analyses reported for these particular fuels was considered inadequate to justify definite conclusions regarding the precision of this determination.The investigation described in this report was made at the request of Committee D-5 on Coal and Coke, A.S.T.M. (A. C. Fieldner, chairman), to secure additional information regarding the errors of the volatile matter determination for anthracite, low-temperature coke, and subbituminous coal; the last fuel also gives trouble in this determination, The committee has recognized that the allowable differences between duplicate determinations of volatile matter for these fuels as given in the standard methods are perhaps too stringent and may require revision."

Dec 1, 1943

By Plato Malozemoff

Our young, technically oriented people today are entranced by the space program, by physics that unlocks the secrets of nature, by electronics, and by other new technologies. The mining industry seems to be their last choice. Enrollment in mining schools is dropping and so is the interest of our great universities in mining curricula. The image of the mining industry appears to be one of being conservative, nonprogressive, resistant to change, and lacking in excitement and challenge. I submit that this public image is wrong. While the initial development of mines is usually slow and seemingly plodding, the problem of solving the imponderables of nature-the ore emplacement, its structure and physical characteristics, its response to recovery processes, and its probable ultimate profitability-is stimulating to the most acute and searching of minds and requires careful application of a combination of many technologies. The paths to obtaining the desired results must be within the bounds of reasonable expenditures in the early stage of development when risks are still high, and this financial discipline is a further stimulus to the imaginative search for the right answers.

Jan 6, 1968

The Mineral Resources Act 1989 was assented to on 25th October, 1989 after more than two years of consultation and negotiation between Government, the mining industry and other affected parties particularly the major rural organisations.The legislation proposes major conceptual changes in a number of areas and adopts a totally new approach to the definition of land and the mechanisms available to the mining industry for accessing such land.Unfortunately the passage of the legislation through Parliament coincided with the lead-up to the State election. Ultimately it became an election issue generating much adverse comment in the media particularly from rural and landholder groups. It was obvious that much of this anti-mining propaganda resulted from a lack of understanding of the legislation and the benefits that flow to the majority of landholders as well as the mining industry.It is essential that the contents of the Mineral Resources Act be thoroughly understood by all parties. Only then will all the State's resources be able to be developed in a multiple land use environment.This paper outlines the philosophy behind the new Act and the more important provisions contained therein.

Jan 1, 1990

By B. C. Scott, A. Baker

The Pitch mine of Pinnacle Exploration, Inc. is in the Marshall Pass district, thirty miles east of Gunnison, Colorado. This is a new mining district, having come into existence as recently as 1955, when uranium mineralization was discovered rather late in the days of the uranium boom. There have been three other mines in the district, all of them now inactive. Two of these produced a few hundred tons of very high-grade uranium ore, and the third, Pinnacle's Little Indian 36 mine, produced a few thou- sand tons of lower grade ore. Pinnacle was one of the first companies in the district, and was able to acquire a large acreage. The first two years of exploration were essentially wasted in looking for Plateau-type deposits in a mineralized sandstone bed, but this "wasted" work produced two specific items that paid off. One was an ore-grade outcrop that ultimately became the Little Indian 36 mine, and the other was a boulder of very high-grade uranium ore that eventually led to the discovery of the Pitch mine; however, the actual source of the boulder still has not been found.

Jan 5, 1961

By J. A. Reizes, C. A. J. Fletcher, T. Jancar

Spirals play an important role in fine coal and mineral processing. To date, almost all spiral designs have been empirically based. Although many operational units have evolved utilising this approach, it does not necessarily lead to optimal spiral designs. This paper presents the preliminary results of a collaborative computational and experimental research program to understand the detailed separation process which will ultimately lead to a parametric assessment of alternative spiral designs through computational simulation. Unlike the empirical approach, a computational simulation is only subject to the fundamental physics of the fluid flow. No prior knowledge of the generic spiral flow is necessary. The computer code implements a robust finite volume technique to predict the three dimensional fluid motion. A height function method is used to model free surfaces and the code is capable of handling arbitrary spiral geometries. Preliminary validation of the computational simulation is carried out through analysis of an existing spiral design -the Mineral Technologies LD9 unit. Computational flow predictions are compared with experimental measurements obtained using a number of techniques, including sampling and flow visualisation, for flow test cases where no solid particulate is present.

Jan 1, 1995

Optimising a mining or a quarrying operation about the overall cost is quite a challenge as there never is a situation where we have exactly the same conditions regarding rock properties, explosives' performance, mining equipment or evironmental restrictions. The amount of endless influencing parameters and variables make the evaluation process difficult. The enormous progress we have seen during the recent two decades in computing has however significantly increased our ability to evaluate and process the information gathered, and refine our existing prediction models. Refined models demand an increasing volume of good quality information to show reliable conformity with reality. There is a great need for co-operative work in the mining and quarrying society if we shall be able to screen all available data, systematically find the key-parameters influencing the results and to build robust scientific models. No organisations today have all the skilled people needed or can afford to hire the necessary specialists in all the overlapping branches. This paper highlights some on-going work where the Dyno Explosives Group is adding some new pieces to the giant jigsaw puzzle representing the ultimate model of the mining and quarrying operations we all of this society would like to see completed.

Jan 1, 1995

Nearly eighteen months ago Newmont Waihi Operations joined with the local district council and members of the Waihi community in the initiation and running of a community liaison forum.   This forum û the Waihi Community Consultative Committee (WCCC) û was set up with the objective of improving communication, providing a forum for discussion and ultimately working through a range of issues relating to the future of the town and district after the projected closure of Martha Mine in late-2006.   After 18 months of meetings where all represented groups have presented their views, the challenge now is to work together to investigate likely options, seek sources of funding, produce business proposals and plan for the future of Waihi in what we call the Golden Legacy Project.   This paper backgrounds the companyÆs experiences to date, the issues the group has addressed and its proposals for the future. Methods employed to set up an effective community liaison forum are considered, drawing on specific examples from the WCCC. The actions and structures required to ensure effective and ongoing community æbuy inÆ at all levels are also discussed.   This paper develops themes addressed in Taking it to the Streets presented in 2003.

Jan 1, 2004

By P Lilly

Blasting is the primary comminution process in most mining operations. This process involves the highly complex and dynamic interaction between two main components. The first is the detonating explosive and the second is the rock mass into which the explosive is loaded. The mechanical properties of the rock material (such as dynamic strength, tensile strength, dynamic modulus and fracture toughness) are important considerations in understanding the blasting process. However, it is the characteristics of the geological defects (joints, foliation planes, bedding planes) within the rock mass that ultimately determine how effectively a blast performs in terms of fragmentation, all else being equal. The defect characteristics include, but are not limited to, their orientation, spacing, and mechanical properties. During the blasting process, some of the geotechnical characteristics of the rock mass are substantially changed. From the blasting outcome point of view, the most notable and important is the change in fragment size distribution that the rock mass undergoes. The pre-blast in situ defect-bounded block size distribution is transformed into the post-blast muckpile fragment size distribution. Consequently, it is fundamental to our understanding of and ability to predict the blasting process that both the blastability of a rock mass and its transformation into the fragment size distribution can be appropriately quantified.

Jan 1, 2001

By Jeffrey R. Kelly, Paul M. Kubera, Richard A. Howk

Mixing of solid-liquid slurries is a unit operation that is widely encountered in the minerals processing industry. Applications may range from simple slurry storage in open tanks to complex chemical reaction systems under extreme conditions of temperature and pressure. The specific process requirements dictate both the degree of mixing required and the type of agitation employed to achieve the desired results.' Many continuous-flow process applications feature tanks operating in series to provide a discrete number of stages and a known residence time for the slurry. Because these tanks operate at a constant level in an overflow mode, the mixer must maintain uniform solids concentration and size distribution throughout the tank; failure to achieve uniformity results in accumulation of coarse solids in the tank, ultimately leading to a process or mechanical failure. Downward-pumping, axial-flow mixing impellers are widely employed to produce uniform solids suspension. The specific impeller type, number, size, and power draw is a function of each given situation. The use of high-efficiency, fluid-foil impellers (Figure I) has evolved as a recognized standard for these flow­controlled applications. Recent small-scale experimentation and full-scale experience has demonstrated that, when uniformity is required, capital and operating expense can be minimized by employing an additional upper impeller pumping in the upward direction.

Jan 1, 1995

By W. G. Woolnough

Production of oil in Australia is negligible at present. A very small quantity of crude is being recovered from lean pumpers in Victoria, and a little activity is evidenced in Queensland, where two new wells were sunk during 1934. One of these, at Warooby Creek near Roma, obtained a noteworthy gas flow, but no oil production has been recorded. Geological investigation is going on in Western Australia, but no drilling activity is apparent. The "boom" in oil prospecting came to an end when the wave of depression swept over the country, and the investing public turned its attention actively towards gold. There is great activity in gold prospecting at present. I still maintain as strongly as ever that the prospects of obtaining flow oil in Queensland, Western Australia and Victoria are good, and that really scientific methods must ultimately succeed. Active and excellent geological work is being carried out in the Mandated Territory of New Guinea, and it is reported that drilling is likely to be undertaken next year. Matters in Papua are at a standstill. The question of extraction of oil from the oil shales of New South Wales and Tasmania is perennially active, and attempts to exploit this source commercially are renewed from time to time. Hydrogenation of coal is also receiving a good deal of attention.

Jan 1, 1935