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By H. D. Goodfellow, R. A. Elliott

"This paper covers the evolution of large mills and autogenous grinding and compares grinding practice in the iron ore industry with that in the base metal industries. Comments on novel methods of grinding are presented for discussion. Recent developments in the field of classification are briefly reviewed. A systems analysis approach to grinding circuits is discussed. Finally, a point is made for establishing a group within the industry with the purpose of developing a comprehensive evaluation of grinding research and development."

Jan 1, 1971

By F. J. Alcock

THE Magdalen islands have recently been attracting attention as a possible source of manganese. As early as 1880 small masses of manganese oxides were known to occur in the soil and at least one attempt was made to develop them. In 1939, after the outbreak of war, interest in the possibilities of the field was again aroused and during the winter of 1939-40 claims were taken up by two groups of Toronto interests. The islands also contain large quantities of gypsum. During the summer of 1940, the writer mapped the islands geologically, giving particular attention to a study of the manganese occurrences. For a base-map, the chart of the islands was enlarged to a scale of half a mile to an inch. Additional roads were added from traverses carried out in connection with the geological work, and form lines with approximate 100-foot intervals were put on from barometer readings. The geological map is the first that has been prepared of the islands. Previous Work In the summer of 1880, James Richardson of the Geological Survey of Canada studied the rocks of the islands and his r~port concerning them appears as Part G of the Report of Progress, 1879-80. In 1903, J. Obalski, Inspector of Mines for the Department of Lands, Mines and Fisheries of the Province of Quebec, visited the islands, chiefly to investigate the occurrences of manganese and gypsum, and his notes are found in the report on mining operations in the Province for that year. Around 1890, Robert Chalmers of the Geological Survey paid a visit to the islands, and his observations, which chiefly concerned the surface geology, appear in the Annual Report of the Survey, Vol. VII, 1894, Part M, p. 94. The next geological work was carried out by John M. Clarke, Director of the New York State Geological Survey. Clarke paid many visits to Gaspé peninsula between the years 1900 and 1920, collecting fossils and gathering h1s~orical data, and extended his investigations of Gaspé county over to the Magdalens. His Observations on the Magda/en Islands is included in the New York State Museum Bulletin 149, seventh report of the Director, 1910.

Jan 1, 1941

By Thomas M. Ware

"MR. Chairman, our Honourable Minister, Mayor Cole, it is a pleasure for me to come here, and join with you in one of the largest industrial shows ever held in Saskatchewan.It is an honour to be asked to keynote your meeting, to help mark an early chapter of this new industry for Saskatchewan. God has placed in our hands a new resource for His man on earth. This store of potash, 350 million years in the making, offers a vital resource to help man support his advanced intellect for thousands of years. It is a gift so large we must all wonder at its purpose and our responsibilities in serving our fellow man with it.We who are here to plan and implement the development of this essential mineral resource enjoy a great -privilege; and we share a great responsibility -to see that the billions of tons of potash which have waited beneath these prairies for millions of years are widely and wisely used to nourish the earth through future millenniums.To know the true value of potash, to be able to bring forth this re-source from over 3,000 feet deep in the earth, to establish markets and develop its potential worldwide is all part of our great heritage from generations past. So I think it is fitting on this occasion that we reflect for a moment on this heritage, to help us assess the responsibilities of its future development."

Jan 1, 1966

By A. Giacomini, M. Nazem, E. Fathi Salmi

"Numerical simulation of collapse of tunnels in weak rocks is one of the challenging problems in rock mechanics. Collapse can impose technical and financial difficulties during the construction of underground excavations. This phenomenon, particularly in shallow excavations, may lead to propagation of a caved zone toward the surface and formation of chimney subsidence. Chimney subsidence has numerous catastrophic consequences such as the adverse environmental impacts and damage to surface structures in vicinity of excavations. Due to the importance of subsidence in civil engineering, the main goal of this study is to propose an appropriate method for preventing the formation of subsidence in shallow tunnels in weak rocks. The Dolaei road tunnel is investigated as a case study, where a large chimney subsidence has occurred. The geology of the area and the geostructural characteristics of the rock mass surrounding the tunnel are briefly reviewed in this paper. Two-dimensional as well as threedimensional numerical simulations are conducted to study the tunnel stability. Moreover, the effects of staged excavation and pre-supporting method on controlling the ground movements are studied. Outcomes of this study indicate that employing forepoling and staged excavation can be a practical remedy to control the ground movements and prevent the formation of chimney subsidence.INTRODUCTIONPredicting the formation of subsidence, mainly sinkhole subsidence over civil or mining excavations, is a very challenging task. An accurate prediction of subsidence is required for selecting an appropriate control and mitigation system to reduce the level of ground movements and its impact on the surface life (Bétournay et al. 1994; Leca and New 2007). Excavations, particularly in weak grounds, could result in surface subsidence; they modify the in-situ stress conditions as well as the hydrogeology of the area. Construction of unsupported excavations in soft soils and relatively weak rocks usually leads to the formation of a failure zone behind the face. In a very soft ground, the failure zone can extend towards the ground ahead of the tunnel face. Propagation of this zone toward the ground surface results in generation of sinkholes."

Jan 1, 2015

By Nick Vayenas, Ming Cai, Hongbin Zhang Lorrie Fava, Enrique Acuña

"A hybrid methodology is proposed to improve the accuracy of Diesel Particulate Matter (DPM) concentrations simulated in a ventilation network model by using Computational Fluid Dynamics (CFD). DPM, as a primary concern for underground hard-rock mines, has been studied in two dominant numerical models, ventilation network solvers and computational fluid dynamics. Ventilation network solvers are efficient, but they are not able to provide three-dimensional DPM concentration contours and only accept area-average DPM data as input. CFD simulations are time-consuming, but generating DPM concentration results with high accuracy. Besides, both monitoring points and planes can be created in a CFD model, which can take both point data and area-average DPM data as input. The hybrid methodology is intended to combine the advantages of the two by using the CFD results to update the network model results at key locations. A field study was conducted in a dead-end heading in an underground gold mine in the United States. Real-time DPM monitors were used to collect data. A CFD model and a network model were built for the experiment area. The CFD model was calibrated to the experimental data. In the study presented here, results from a calibrated CFD model are converted to equivalent diesel emission rates in the ventilation network model at a shared outlet. The hybrid methodology is used to provide better input for the network model. INTRODUCTION Mine ventilation system is one of the most important parts for an underground mine. It not only provides fresh air to the personnel but also helps clear the contaminants generated from the diesel-powered equipment. For most underground metal and non-metal mines, diesel particulate matter is the main contaminant. It is also the focus of this paper."

Jan 1, 2019

By T. Adamcewicz

The province's lignite resources lie mainly in the south, extensions of the much larger deposits in Montana and North Dakota. Because of planned additional capacity, conventional steam power generation will probably remain as the dominant resource usage for many decades. Conversion of coal to other energy forms is receiving emphasis and in the future will compete with steam power generation in terms of quantities used.Economic deposits, minable by present-day technology, have been generally defined. Because a large percentage of the total lignite resource is in seams containing multiple partings, future extraction will become much more difficult and capital intensive.Increased public involvement will ensure that the impacts of future coal mining and usage operations are compatible with environmental and social objectives.

Jan 1, 1982

By P. R. Clark, M. D. Gleghorn

"IntroductionAt TransAlta Utilities Corporation's Highvale Mine, located west of Edmonton, Alberta (Fig. I and 2), dragline stripping has proved to be a practical and economical method of overburden removal and future plans have been based upon the continued use of draglines (Fig. 3) as the major stripping equipment (Williams, 1979, Nikols et al., 1986). However, long range planning has shown that the capacity of draglines alone will be exceeded in the early 1990s as mining progresses into deeper overburden cover (Tapics, 1983). Strip ratios will increase from I.3 bank m!/ t of coal in 1985to 4.5 bank m3 / t in 1995. During this period the depth of overburden will increase substantially and the areas to be mined will be characterized by weak soils including glacially displaced overburden. This increased overburden depth in relatively weak soils will make it impractical to _continue side casting by draglines without prestripping in advance. In 1983, a major investigation was initiated to determine what additional overburden removal equipment was appropriate to the Highvale operations, and recognizing the long delivery times of this major equipment. when it would be required. This paper describes studies and tests which were undertaken in 1983 and 1984 to select prestripping methods and equipment for the future operation of the mine.Previous planning studies have shown that with the current burn schedule and with the economies of progressing from low cover to high cover, as has been practiced in the past, overburden volumes will exceed the capacity of the existing draglines in the early 1990s (Fig. 4). These previous studies had placed reliance on (I tandem dragline operation for future overburden removal requirements up to a depth of 45 m throughout the Highvale Mine. New drilling together with the associated geotechnical studies and some detailed planning on the practicality of using tandem draglines, created concerns about their universal application. Even without considering geotechnical conditions there was a depth limitation to tandem dragJines and substantial prestripping would be required to achieve the ultimate depths."

Jan 1, 1987

"Block caving is the preferred underground mining method to profitably extract massive, low-grade orebodies; however, lack of cave access inhibits understanding the rockmass response to mining, which is needed for safer, more productive operations. Combining large datasets from multiple sources with virtual reality scientific visualization (VRSV) is an alternative method for understanding complex cave behaviour, by providing virtual access to the cave. A customized VRSV module was developed at UNSW Australia to investigate rockmass response to undercut developments at a case-study block caving operation. Time/sequence effects are investigated in rockmass response to blasting, which is an important factor in hard-rock mines.RÉSUMÉ La méthode d’extraction souterraine par blocs foudroyés est la méthode préférentielle pour extraire rentablement des gisements massifs à faible teneur. Toutefois, le manque d’accès à la chambre restreint la compréhension de la réponse de la masse rocheuse à l’exploitation, ce qui est nécessaire pour obtenir des opérations plus sécuritaires et plus productives. La combinaison de grands ensembles de données de multiples sources avec la visualisation scientifique par réalité virtuelle (VRSV) constitue un autre moyen de comprendre le comportement complexe de la chambre en fournissant un accès virtuel à la chambre. Un module de VRSV sur mesure a été développé à l’Université de Nouvelles-Galles du Sud (UNSW) en Australie afin d’étudier, dans une étude de cas d’une exploitation par blocs foudroyés, la réponse de la masse rocheuse aux développements de galeries de sous-cavage. Les effets de temps/séquence sont étudiés dans la réponse de la masse rocheuse au sautage, ce qui est un facteur important dans les mines de roches dures."

Jan 1, 2016

By R. Stach, S. Gola, P. Zgrzebski, K. Soroko

"The future of Polish copper mines KGHM Polish Miedz S.A. will be associated with mining at depth. At present, technologically advanced measures are being introduced to minimize the adverse influence of the environmental hazards on people working underground. Polkowice-Sieroszowice mine is the only mine in Poland where mining takes place in copper and salt deposits. On the basis of the current and anticipated methods of ventilation of a selected ore deposits the paper will analynze a number of solutions enabling planned mining of copper ore deposit, while minimizing the impact of natural aerological hazards in working areas. INTRODUCTION The future of copper ore mining, carried out by KGHM Polska Miedz S.A., will be based on mining from continuously greater depths (Butra, 2015). It is forecast that this will be accompanied by an increasing climatic hazard, resulting from an increase in the original temperature of rocks of more than 45°C as well as gas and geodynamic hazards (Soroko, 2015; Andrusikiewicz, 2015). Due to the safety of underground teams, a need arises to develop methods eliminating the adverse impact of the natural hazards, down to a level enabling the mining activity to be carried out on an industrial scale while maintaining favourable economic parameters. Current depths of the copper ore deposit being developed are effectively verifying the technical methods and measures employed to date for eliminating the natural aerological hazards. Amounts of air supplied to mining areas, with lengthy transport routes, are becoming insufficient for miners’ temperature safety, whereas increasing the power of cooling air-conditioning stations for cooling the air undermines the economic legitimacy. However, along with the temperature hazard, a significant problem at the current depths is an increase in gaseous occurrences in the headings’ areas. The concentrations of natural harmful gases found, even with the values below the permissible concentrations, in the case of limited amounts of air and/or low airflow rates, may pose a considerable danger to the workers. The hazards referred to are currently the major factors determining the advance of headings, above all in mining sections, being the outcome of geological structure and depth of lying of a deposit. However, at the current depths of mining minerals from deposits, room-and-pillar mining systems employed also have a decisive impact on the increase in natural aerological hazards."

Jan 1, 2019

"Pilot plants for pressure hydrometallurgy represent special design and project execution challenges. Over the past twenty years, Zeton has designed and fabricated a variety of world-class pressure hydrometallurgical pilot-plant facilities for the nickel industry, and this paper discusses design considerations and strategies related to such projects. Project execution methods are also discussed, and guidance is given for the selection of materials of construction and for the selection of appropriate pressure and temperature design points for pressure hydrometallurgical pilot equipment. The paper concludes with a discussion of the need for process similarity with future commercial operations and the realities of pilot-scale equipment.INTRODUCTION The process technology developer or owner and the designer/fabricator of a new pilot-plant facility are faced with some difficult technical choices even after the decision to build a dedicated plant has been taken. A pilot-plant project is usually on the critical path of a large commercial project involving investments many multiples greater than the capital cost of the pilot plant. Schedule savings in the design, manufacture, and commissioning of the pilot plant or in a rapid completion of the experimental program can be disproportionately beneficial to the overall development project. However, inappropriate shortcuts resulting in major oversights can be disproportionately problematic. A number of considerations and suggestions for both the project execution approach and the process engineering design of pressure hydrometallurgical pilot-plant facilities are presented as a guide for potential owners and operators of new pilot-plant equipment and facilities. These suggestions are particularly applicable to the nickel industry, where the majority of our firm’s prior hydrometallurgical experience was obtained. This paper is an update to an earlier publication (Martin, 2004), offering an opportunity for a new generation of metallurgists and engineers to learn the specialist requirements of pilot- and demonstration-scale plant design, which are key functions in the development and commercialization of new processes."

Jan 1, 2017

By Constantin D. Pitis

?Demand-side measure" means a rate, measure, action or program undertaken to conserve energy or promote energy efficiency?? (BCUC, 1996) In actual economical environment, business sustainability requires high-efficiency technological processes. That is why the efficiency concept has to be present at all levels of industrial activities. Nowadays, some purchasing decisions are still driven predominately by the purchase price, in spite of the evidence that such price represents up to 5 % to 7 % of the total costs of ownership with full consequences of energy efficiency and the impact on total ownership costs. The paper presents essentials of converter types and basics of the Global Efficiency (GEff) Concept that has been promoted over the last few years in South African industries (Pitis et al., 2006/7). GEff concept is proven as a useful tool used on price-efficiency decisions. Theoretical and technical aspects of this concept were substantiated with case studies. First part presented in this paper will describe how GEff concept was used on price ? efficiency decisions when single input or direct converters and systems (considered as low value equipments) have been replaced. Besides the impact of energy savings and new innovative developments, the paper suggests general other benefits of: ? Technical and economical performance improvements and competitiveness of mining corporations to international standards; ? Defusing incipient energy crisis in the sector; ? Improving environmental conditions; ? Creating new job opportunities in mining sector. Proposed concept in this paper could be further developed as models of improving companies? corporate energy policies.

May 1, 2010

By Chris Twigge-Molecey

"Over the last 50 years there has been a dramatic evolution in the metallurgical engineering field in Canada. In the 60s the field was dominated by large American and UK groups, often selling major process and equipment packages. The local content was limited to wrap around facilities and the civil and structural work. The mining and metallurgical companies had strong internal teams to lead these projects. Over the decades and business down cycles the large foreign contractors disappeared or re-structured and the mining companies largely shed their engineering and project management groups. The resulting gap was filled by a cadre of local specialist engineering companies, some of whom have grown to be world leaders in the field. The paper traces this evolution and examines the underlying causes and consequences."

Jan 1, 2015

By Zihe Ren, Edouard Asselin, Marcus Tomlinson, Tianbi Zhang, Jing Liu

"Raman spectroscopy is used to quantify the extent of disorder in the carbonaceous matter associated with preg-robbing ores. Previous studies of Goldstrike ores showed that the height and width of the peaks for the “D” (disordered) and “G” (graphite) bands, the so-called “Raman ratio” had a strong correlation to the preg-robbing value (PRV) measured for various ore samples. A brief literature review on Raman spectroscopy as it applies to preg-robbing ores is presented. Further, recent studies, presented here, have shown no correlation between the Raman ratio and the PRV for a wide variety of ores. This suggests that the extent of organic carbon crystal disorder is not the main factor in determining preg-robbing characteristics.INTRODUCTION Preg-robbing may arise from natural carbonaceous materials in the ore. Several mechanisms have been proposed in the past decades including a physical sorption process by the carbonaceous matter, or via the reduction of aurocyanide at the mineral surface (Abotsi & Osseoasare, 1986; Afenya, Osseoasare, & Abotsi, 1983; Tan, Feng, Lukey, & Van Deventer, 2005). Nevertheless, the mechanisms of preg-robbing remain poorly understood. Understanding the nature of the preg-robber is of practical importance for the selection of a suitable treatment process. Fine carbon particles in the ore have been recognized as preg-robbers due to their similarity to the activated carbon used in the carbon in leach (CIL) or carbon in pulp (CIP) processes. Previous research has illustrated that the activated carbon (also referred to as amorphous carbon in some literature) has a much higher absorption ability than pure graphite with high crystallinity (Adams & Burger, 1998). Adams et al (Adams, Swaney, Friedl & Wagner 1996) concluded that carbonaceous matter is largely responsible for the overall preg-robbing capacity of a given ore. However, the mechanism of carbon preg-robbing was still not clear mostly due to the complexity of amorphous carbon and its behavior in different solution matrices, and at different pH and temperature (Adams, 1990, 1993)."

Jan 1, 2017

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

By James Mackie

The Vancouver Stock Exchange (VSE) has been providing venture capital for start-up companies since 1907. Ninety years' experience in the junior mining industry has enabled the VSE to develop policies and procedures tailored to the unique needs of start-up companies. Policies and procedures applicable to listed companies are documented in the Corporate Finance Services Department "Policy and Procedures Manual." Approximately 50% of the companies listed on the VSE are in the mineral exploration and development business. The largest number are exploring base metal, precious metal or diamond properties. A recent count shows that about 20 companies are exploring industrial mineral or non-metallic deposits. The minerals sought by these companies include limestone, decorative stone, building stone, lava rock, wollastonite, zeolite, garnet and graphite. There are two basic routes to obtaining VSE financing for an industrial mineral property. The owner can either sell an interest in the property to a listed company or form a company and have it listed on the VSE. In each instance, the listed company is responsible for raising funds to develop the property. A typical financing consists of the sale of company securities byway ofeitherprivate placement or prospectus offering.

Jan 1, 2001

By Guoqiang Lan, Jun Song, Bin Ouyang

Rare-earth pyrochlores, commonly exhibiting anomalously low lattice thermal conductivities, are considered as promising topcoat materials for thermal barrier coatings. However the structural origin underlying their low thermal conductivities remain unclear. In the present study, we investigated the phonon properties of a group of RE pyrochlores, Ln2Zr2O7 (Ln = La, Nd, Sm, Gd) employing density functional theory and quasi harmonic approximation. Through the relaxation time approximation (RTA) with Debye model, the thermal conductivities of those RE pyrochlores were predicted, showing good agreement with experimental measurements. The low thermal conductivities of RE pyrochlores were shown to largely come from the interference between the low-lying optical branches and acoustic branches. The structural origin underlying the low-lying optical branches was then clarified.

Jan 1, 2015

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée.AURIX®100 RESINAuRIX100 resin is a crosslinked polystyrene alkaline resin developed by Henkel (Virnig, Mackenzie, & Adamson, 1996). The resin beads are off-white in colour and spherical, with a nominal size of 100% +600 µm. This resin is highly selective for gold and silver over many metals, by way of extracting precious metal–cyanide complexes from leach solutions with a pH of less than 11.5. The higher end of the pH scale produces the best selectivity according to the order of preference: Au > Ag > Hg > Zn > Ni > Cu > Co > Fe. Purolite produces the resin and Gekko Systems maintains licensing of AuRIX100 resin for use in its G-REX column, as part of its unique suite of gravity gold–handling equipment.Significant cost savings over carbon-in-solution (CIS) systems are realized with AURIX100 resin: approximately 4–12% in capital savings and 27–40% in operating costs (Virnig, Mackenzie, Katsikaros, & Gray, 2004). Additionally, AuRIX100 resin is not susceptible to fouling; that is, the resin does not load with inorganic salts or organic compounds that would affect the loading and extraction of precious metals. To counter any potential for fouling by inorganic salts, a dilute acid wash is periodically conducted in service on the resin to unblock resin pores."

Jan 1, 2017

By Derek Apela, Coralee Heske, Bunyamin Kahraman, Muhammad Adi

Effective blast fragmentation is essential in underground mining, as it directly influences downstream processing efficiency and operational expenses. This study investigates the application of Non-Newtonian Fluids (NNF) as stemming materials, presenting a novel method to enhance energy confinement, minimize environmental impact, and optimize blast performance. NNFs exhibit shear-thickening behaviour, enabling them to transition between fluid-like and solid-like states under stress, which renders them suitable for regulating explosive gas ejection during blasting. Field trials were performed by Vale Base Metals in Thompson, Manitoba, in their underground nickel mine to evaluate conventional slag stemming against NNF-based stemming in production-scale blasts. Emulsion explosives were employed, and blast performance was assessed through velocity of detonation (VOD) measurements, vibration monitoring, and AI-assisted fragmentation analysis using WipFrag. Preliminary results indicate that NNF stemming improves fragmentation, resulting in a reduction of D50 by as much as 38%, enhances energy confinement, and may decrease the incidence of hole plugging and re-drilling in subsequent blasts. This study presents an alternative to conventional stemming methods, highlighting potential advantages for enhanced safety, efficiency, and sustainability in blasting operations. Additional research and field trials are necessary to improve implementation protocols and facilitate the widespread adoption of this unique method in the mining sector.

May 4, 2025

By A. H. Burns

"Regenerative and recuperative burner systems require advanced combustion techniques to minimize NOx emissions. Various methods of pollutant minimization and furnace design considerations are described. Cited examples are a large high temperature furnace and a small Zinc vaporizing furnace. The concept of total carbon footprint is introduced. The application of Biomass combustion as an effective method of cost and green-house gas (GHG) reduction is discussed. Practical considerations of scale, location and process limitations are discussed. Two examples of biomass fired equipment are cited. Ideal sites have large biomass resources available locally. Processed biomass fuels will be an important substitute for fossil fuel. INTRODUCTIONIn 1992, I presented a paper entitled Combustion Strategies In The Modern Industrial Environment (1992). At that time an abundant supply of cheap fossil fuel made many of the measures I talked about difficult to justify for anything but new equipment.Since 1992 we, as a society, have demonstrated an ability to accelerate the pace of industrial and societal change. The term industrial revolution applied to this age of incessant change is completely meaningless, implying a discrete moment in historical time. What our society has built is a system capable of unfettered, continuous and accelerating technological change. With this change comes an increasing demand for energy and materials.This year is the anniversary of the Titanic disaster, a moment in time when technological certainty met the caprice of nature and gave us a brutal reminder of what can happen to us if we underestimate that power (Mowbray, 1912). In the intervening interval we have regained the technological arrogance that was lost in 1912 bringing us back to the problems of climate change and the need for sustainable industrial activities.We use advanced mathematics to describe many complex systems, sometimes with disastrous results. For example there has been a recent attempt to model the global economy as a completely deterministic system. This premise is flawed at its foundation as human nature and emotion are indeterminate constants in the equations, yielding probabilistic solutions at best. As engineers we are all familiar with stiff problems. The solution to such a problem is meaningless and we have all had the misfortune to live through and rue the effects of that miscalculation over the last few years."

Jan 1, 2012

By L. Price, R. Hortie

Movement of ore and waste from the Hilton Mines pit is accomplished by truck haulage. With the aim of reducing costs, a study of truck fleet replacement was initiated. The study included on-site short-term tests and longer-term rental purchase agreements for haulage trucks. The operation and maintenance characteristics of different trucks, along with projected haulage conditions, were used to prepare cash flows, from which the most advantageous trucks were selected. The results of the study and implementation of the recommendations gave a cost saving greater than had been estimated. The study also indicated areas where improvements could be made, and resulted in much more attention being paid to road conditions, the training of operators and mechanics, and the development of a practical preventative maintenance scheme.

Jan 1, 1971