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By Matthew Violot

Introduction ?Located off highway 6, approximately 5 km, SW of Thompson, Manitoba ?Base metal mine: Nickel? Maximum Depth: 4100 ft ?Started Production in 1966 (INCO, 2006)?Halted in 1978?Re-opened in 1989 ?Two types of mining:?VBM (vertical block mining)?Cut and Fill 1.1 Problem ?Birchtree mine is experiencing failures and undesirable dilution in some of their stopes. ?Time can have a large effect on open stopestability. ?Birchtreeis interested in how time is affecting the stability of their stopes. ?The study focuses on the lower 84 complex, which extends from 2750 to 4100 foot level.

Nov 1, 2011

By Patrick M. Y. Waye

As mines utilise more automation in mining operations to improve efficiency and safety, a corresponding increasing demand is placed on the transport of information. Some of the recent technological advances in underground telecommunications are described for various data, voice and video applications. In particular, two new innovative underground communication systems are described, one with high speed data at 30 Mbps and the other for mine wide evacuation and safety applications. The high speed data system incorporates stateof- the-art data networking technologies and the existing leaky cable narrow band radio channels. The new system provides over the same basic infrastructure the high speed data network at 30 Mbps TCP/IP Ethernet with 100 Base-T interconnection, plus 32 narrow band radio channels. The second system is a system for mine wide evacuation with "through the earth" communication infrastructure. Emergency situation can be communicated to and from all the miners within seconds through a central control location. The technology involved does not require leaky cable or any other similar transmission media installation. Many applications are possible, including warning miners of emergency situations, mine rescue operation to communicate with trapped miners, regular reporting from miners working alone.

May 1, 2001

By Rees J. Llewellyn

High chromium white irons can be formulated to provide required combinations of abrasion and erosion wear resistance, toughness and capability to withstand corrosion attack. As a consequence, they are used widely in casting form throughout the mining/mineral processing industry, particularly as components for slurry pumps and also as mill and crusher liners, laminated wear plates in chutes and hoppers and in valves, nozzles and cyclones. Traditional cast chromium molybdenum and high chromium white irons for wear applications are covered in ASTM A532 Classes 11 and 111 and are also available as comparable proprietary alloys. They rely on heat-treated, hypoeutectic microstructures containing a high volume fraction of very hard eutectic/secondary metal carbides and martensite to provide extremely high wear resistance. The ability to increase the carbide volume fraction and hence achieve higher wear resistance, has been limited because of severe casting difficulties encountered when carbon and chromium contents are raised and hypereutectic alloys with structures also containing coarse acicular primary metal carbides are produced. The limitation has been overcome and cast hypereutectic chromium white iron pump components have established themselves in a wide variety of mineral processing service applications. Comparisons will be made between the microstructures and wear test performance data for the various alloy types and details will be provided of the service performance improvements that have been achieved through the use of hypereutectic chromium white irons.

May 1, 2004

By P. Srinivasan

Corrosion is a major operational problem in amine-treating plants causing significant expenditures each year, Corrosion may become more severe when the amine plants contain process contaminants ? namely heat-stable salts. The heat-stable salts enter the plants with feed-gas streams and makeup-solution, and/or are produced within the plants by reactions of alkanolamine and available carboxylic-acid anions, This work investigated interaction corrosion effects that may exist in amine-treating plants containing a mixture of heat-stable salts, The investigation was experimentally carried out in a 5 kmol/m3 monoethanolamine (MEA) solution containing 0,20 mol/mol carbon dioxide (CO2) loading at 80°C under atmospheric pressure using carbon steel 1018, Six heat-stable salts, including formate, oxalate, bicine, acetate, thiosulfate and chloride, were tested with a series of salt combinations, Potentiodynamic Polarization, Tafel Extrapolation, and Cyclic Polarization were used for revealing corrosion behavior, determining corrosion rate, and examining the pitting tendency, respectively, Results show that thiosulfate induces the most corrosive environment when present either individually or in the form of salt mixtures.

Jan 1, 2005

By R. D. Clarke, E. De Souza

"A framework for ventilation planning, with a focus on planning to the end-of-mine life, was developed for the Diavik Diamond Mine, Northwest Territories. This framework was successfully used by Diavik’s mine engineers to select a cost-effective ventilation plan that met the life-of-mine requirements. The framework achieved this result by reconciling the production plan with the ventilation plan. A set of design acceptability criteria was created and a PICK (possible, implement, challenge, kill) chart was used to quickly narrow down the generated ideas for detailed assessment and economic analysis. RÉSUMÉ Un cadre de planification de l’aérage, qui met notamment l’accent sur la planification jusqu’à la fin de vie de la mine, a été développé pour la mine de diamants Diavik. Les ingénieurs miniers de Diavik ont su mettre à profit ce cadre pour sélectionner un plan d’aérage rentable qui répondait aux exigences propres à la durée de vie de la mine. C’est en conciliant le plan de production et le plan d’aérage que cet objectif a pu être atteint. Un ensemble de critères d’acceptabilité de la conception a été créé et un tableau PICK (de l’anglais possible, implement, challenge, kill, une méthode donnant la priorité à certaines actions proposées ou à des idées visant à résoudre des problèmes) a été utilisé pour rapidement limiter les idées générées et les soumettre à une évaluation et une analyse économique détaillées.INTRODUCTION The Diavik Diamond Mine, Northwest Territories, has been an underground-only operation since 2012 and has a remaining mine life of 8 years. In the first year of underground-only operations, the production rate increased from 60 kt of ore per month to more than 160 kt of ore per month. In subsequent years, this rate was continuously increased (Table 1) because the operation went through various improvement initiatives. By the end of 2016, Diavik’s total production was 0.41 Mt (+22.8%) ahead of the 2012 budget for 2016 production."

Jan 1, 2018

By Michael Harley, E. Guy Charlesworth

"Abstract - Bedding-parallel thrust-hosted gold veins are developed in the Sabie-Pilgrim's Rest goldfield, eastern Transvaal, South Africa. The reefs display a complex history characterized by temporally and spatially overlapping events of similar mineralization and deformation. Recognition of the episodic reactivation of these low angle (5° to 10°) thrust faults implicates high fluid pressures (equalling or exceeding lithostatic pressures). Geochemical constraints limit the amount of fluid-rock interaction and the occurrence of transgressive mineralization within the Archaean granitoid basement suggests that the high pressure fluids originated at depth beneath the Transvaal Basin.Similarities exist between gold deposits of Sabie-Pilgrim's Rest and Telfer, Western Australia as well as Passagem de Mariana, Minas Gerais, Brazil. All deposits are sub-parallel to the enclosing bedding which is shallowly inclined. Furthermore, they are also hosted by contractional deformational structures and are clearly epigenetic in origin."

Jan 1, 1994

By L. H. Cole

FOR many years Industrial Minerals, or as they were formerly called, 'the Non-Metallic Minerals', compared with the metallics, were considered of only minor importance and as such were given scant attention in the technical press as well as in the public press. Those days are, however, happily passing, and thanks, to an appreciable extent, to the constant endeavour of the Industrial Minerals Section of this Institute, established in the fall of 1932 industrial minerals are now assuming the importance to which they are entitled. The term 'Industrial Minerals', when first adopted in this sense by the Institute, was thought to be original in its application, but it is interesting to note that it had been used many years previously by the Queensland Geological Survey in the following publication: SALT Article 1 in Industrial Minerals by B. DUNSTAN, Chief Government Geologist (Publication No. 268, in Part) Queensland Geological Survey, Department of Mines, Brisbane 1920 In Queensland, however, the term embraced some of the metals as well as the non-metallic minerals proper. The lead furnished by Canada in this matter bore rapid fruit, and already the term 'Industrial Minerals' is widely used, not only throughout Canada but in the United States as well.

Jan 1, 1939

By C. Pelley, S. Kelebek, T. Katsabanis, B. Nanthakumar

"As part of a larger investigation on generation of fines from mining activities and their effect on downstream operations, ore samples from Onaping area stockpiles of Falconbridge Ltd were studied. Batch flotation tests were conducted on the stockpile samples and fresh ore samples to explore the effect of stockpiling on grade-recovery performance. Head grade and particle size distribution of the samples from stockpiles were adjusted so that the samples compared are similar to each other. In additional tests, fresh ore samples were blended with stockpile samples at various percentages, representing 27.4, 50.2 and 81.5% of stockpile samples.The samples from stockpiles produced inferior nickel grade-recovery curves compared to fresh ore. The poorer grade-recovery performance was attributable to two factors. First, a significant dilution effect was observed due to the nearly complete flotation of pyrrhotite. Secondly, while pyrrhotite from stockpiled ore became highly floatable, the same stockpiling conditions caused nickel losses that were attributable to non-floatability of some pentlandite.In the case of blending, there was generally insignificant difference in the nickel grade-recovery between fresh and blended samples when the blending cases involved 27.4 and 50.2% stockpile samples. However, an increase in pyrrhotite recovery was observed for both blending cases. At 81.5% blending case, degraded grade-recovery was significant primarily due to the nearly complete flotation of pyrrhotite. There was a small, but noticeable amount of nickel loss for this case. However, for lower ratios of blending this loss was negligible.The increase in pyrrhotite recovery was partly attributed to its activation by Cu and Ni ions. Formation of a significant amount of elemental sulphur was also apparent from analysis of stockpiled samples. It can be concluded that pyrrhotite is mildly oxidized under stockpiling conditions while part of the pentlandite undergoes a more severe oxidation."

Jan 1, 2006

By J-L. Tang

A new rhcoforming processing of Al alloys with component shaping systems apart from slurry preparation systems is experimentally exploited, using the reversible multilevel-speed electromagnetic stirrer, the slurry transfer tool and its coating, the thin plate sample with five steps and rheocasting mould, all of which are independently developed. The results show that semi-solid A356 alloy slurry with shape factor of about 0.85 and particle size of 70~80 µm (under air-cooling condition) could be prepared in 20~25 s, fully meeting the production rate of high pressure die casting. The slurry could be smoothly transferred from the slurry preparation equipment to the rheocasting shot chamber while the slurry temperature of slurry decreases by no more than 3 . The tensile strength and elongation of the semi-solid rheocasting samples could be respectively increased by 11.6~18.2 % and 42.5~50 % compared with the traditional liquid die casting ones, and the rheoforming processing has close affinity with the traditional hot working processes.

Jan 1, 2007

By Eldridge Haynes

IF you ask the average American to define 'total war' he is apt to fumble for an answer. But in Britain everyone knows the answer, because Britain has mobilized its total labour force, including women. If we were to match, proportionately to our population, Britain's mobilization of labour, we should have 60,000,000 people working full time in the armed services, civilian defence, and war industries. Actually we have fewer than 35,000,000 so employed. In Britain two out of every three persons between the ages of fourteen and sixty-five are so engaged. For the first time in the history of any democracy Britain conscripts women for service in the army, navy, and air force. Two hundred thousand British women have been conscripted for the army, known as ATS, meaning Auxiliary Territorial Service. There are more women in the air force than the total personnel of the RAF at the outbreak of the war and almost all of the land base jobs of the British navy are now handled by women. In addition to cooking and office work, Britain's women soldiers and sailors are driving trucks and motorcycles, repairing motor vehicles, packing and repacking parachutes, installing, inspecting, and maintaining gun equipment and ammunition of combat planes after each raid, raising and lowering barrage balloons, forecasting weather, manning harbour craft, sending and receiving radio messages. A normal ack-ack unit is composed of 229 women and 189 men. The women man the gun height finders and predictors, give bearings, and signal to fire.

Jan 1, 1942

By Stopford Brunton

For many years it has been accepted as axiomatic that the greater number of 'veins' or 'leads' in the gold districts of Nova Scotia are of the 'interbedded' type. The corollary to this hypothesis is that the vein or lead will have a continuous hanging-wall of one kind of rock, and a continuous footwall of the same or another kind of rock; but the essential point is that the foot and hanging walls are, according to this theory, both continuous and of uniform composition throughout; and that the vein or lead conforms to the bedding of the adjacent strata. With regard to the deposition of the gold in the rocks, the probability is that the key of the problem is contained in a statement by E. R. Faribault, of the Geological Survey of Canada: "The combined effect of cleavage, jointing, and stratification is to cause the rocks, especially the quartzites, to break into rhombohedral blocks". It is essential to comprehend that the rocks of the Province are no doubt folded into anticlines and synclines; but also it must be fully realized that the gold deposits and pay-shoots do not depend so much upon these as upon the fractures resulting from the disturbance caused by the intrusion of granite masses, and controlled by the combined effect of cleavage, jointing, and stratification. These fractures would form the channels through which the ore-bearing vapours and solutions would rise, and at the junctions of these fractures, where the fracturing was greatest, the easiest passages would be afforded to the ore carriers, with the result that the ore-shoots would be found at or near the intersections of fractures. It is a significant fact that in at least thirteen different districts throughout the Province, operators have at various times remarked upon the occurrence of rich ore at the intersection of 'leads,' 'veins,' 'beds,' etc.

Jan 1, 1928

By W. N. Hamilton

As a result of a test-drilling program conducted by the Research Council of Alberta in 1968, a gypsum deposit averaging 30 feet in thickness, with a chemical purity of 84 per cent gypsum, has been proven to underlie the Clearwater River valley for a distance of 18 miles at depths ranging from near-surface to 300 feet. This and other subsurface deposits in the vicinity of Fort McMurray, Alberta are the product of local hydration of anhydrite beds believed to be the water-insoluble remains of the leached Prairie Evaporite formation of Middle Devonian age, the thick salt section of which is preserved down dip. The effects of salt solution are seen in the disturbed bedding and the intermixture of greyish green shale with gypsum in the core, the shale content being responsible for the rather low chemical purity of the deposit. A similar gypsum deposit, but probably of higher purity, is postulated to occur beneath the Athabasca River valley about 60 miles north of Fort McMurray.

Jan 1, 1969

By Clifford S. Gibson

THE Workmen's Compensation Ace defines Silicosis as "a fibrocic condition of the lungs caused by the inhalation of silica dust sufficient co produce a lessened capacity for work". This fibrocic condition muse exhibit a specific appearance in the X-ray picture of the chest-an appearance which is not characteristic of several lung conditions which can cause lessened capacity for work and which are not due co silicosis. The layman is sufficiently familiar with this subject co know chat, as far as our knowledge goes, quartz is one of the principal objectionable factors in the production of this condition. He should also know that silicosis respects neither geographical nor industrial boundaries. It is as much a factor in some industrial processes (e.g. foundry work, sandblasting) as it is in mines handling ores containing quartz. Its development co a recognizable stage is usually a matter of many years. As yet, its cure is unknown. Its prevention is possible in varying degrees. The layman should also know that the development of fibrosis may be accelerated by breathing in, or living in, any atmosphere containing dust. Few normal adults, particularly those above a certain age, have clear lungs, and fibrosis in varying degrees is noted in the farmer, the steel worker, the clerk, and many others in varied occupations. It is not restricted to miners. Medical and industrial journals, and at times the press, are crammed with data pertaining to this subject, much of which is misinformation. This is particularly true of certain !laces where the preventive and compensation measures for the good o those earning their livelihood in an industry in which silicosis may be contracted are not so far advanced as in our own Province. A great many of these publishings are alarming to the layman. They leave him with the impression that he is taking his life in his hands if he elects to work underground, particularly in a gold mine-that he has at once sold his heritage of health and chat sooner or later he will succumb to the ravages of this ailment. Nothing could be farther from the truth. Actually, under present conditions in Ontario mines, a very small percentage of the men employed ever become impaired by silicosis to the extent chat they must withdraw from the industry. I propose to tell you briefly something of this subject as it affects our mines.

Jan 1, 1937

By G. E. Cole

"Amongst the mineral products of Canada gold holds the second place in value of yearly output. . . . . .The production of gold has increased steadily during the past six years and has somewhat more than doubled in that time. For the past four years Canada has been third among the gold producing countries of the world, surpassed only by the Union of South Africa, and the United States of America," and now yields somewhat more than 9 per cent of the annual output of the world."-"The Gold Situation in Canada". Bulletin of Development Branch, Canadian Pacific Railway. The history of gold mining in Canada is comparatively modern and does not take one further back than the late 'fifties of the 19th century. If the efforts of the early explorers in Canada were expended in "seeking with equal ardour, proselytes and gold", history fails of any record of their success in the search for the precious metal. As early as 1849 not a few Canadians travelled from the east by land and water to the Californian goldfields. In the then settled part of Canadathe east-people were alive to the value of any mineral discovery; but the west, owing to its remoteness and to there being no ready means of communication, was virtually isolated from the east.

Jan 1, 1927

By Terry Keough

Contents for discussion ?Current liner technology ?Innovation of magnetic products ?Development of magnetic wear liners ?Installation and change out method ?Uses and capabilities ?Internal wear liners ?Summary Vulcanized rubber ?Many of you are familiar with using vulcanized rubber to provide wear protection on mining equipment. For years, this was the standard for most mining equipment, and mines spent a lot of money fabricating and lining steel equipment.

May 1, 2010

By Richard Maurice

RÉSUMÉ La restauration du site minier Poirier, à Joutel s?est déroulée entre 1998 et 2001. Le principal élément des travaux a été la restauration du parc à résidus et des zones d?épanchement qui totalisaient 4,5 millions tonnes de résidus répartis sur une superficie de 74 hectares. Les résidus sont fortement générateurs de drainage minier acide. La première partie de la présentation consiste en un bref rappel du concept de restauration suivi d?une description des principaux éléments de travaux avec l?emphase sur les leçons apprises de l?exécution des travaux. La deuxième partie de la présentation est axée sur les résultats du programme de suivi en cours depuis la fin des travaux en 2001. Les éléments de suivi se rapportent à la baisse du niveau de la nappe phréatique à l?intérieur de la cellule, au tassement des résidus dans la cellule, aux mesures de température et d?oxygène à l?intérieur de la cellule et finalement à l?amélioration dans la qualité de l?eau de surface. ABSTRACT The reclamation of Poirier Mine, in Joutel, was carried out between 1998 and 2001. The main component of the works has been the reclamation of the tailings basin and tailings spill area which contained a total of 4,5 million tonnes of tailings and occupied some 74 hectares of ground surface. The mine tailings are highly acid-generating. The first part of the presentation will deal with a brief review of the reclamation plan followed by a short description of the main work components laying emphasis on experience gained during construction. The second part of the presentation will deal with the results obtained from the environmental monitoring program still in progress since the end of reclamation work in 2001. The aspects discussed include the drawdown of pore water inside the covered tailing pile, the settlement of mine waste material, the monitoring of moisture, temperature and oxygen underneath the liner and finally, the reduction of loadings in surface water.

Nov 1, 2002

By Transfert Environment and Society

Transfert?s added value ? Building bridges between project promoters and communities ? Unique expertise in working toward Social License to Operate through meaningful community engagement ? 25 years of recognized innovation and a systematic approach ? Key mining clients: ? Royal Nickel Corporation ? IAMGOLD - Niobec ? Richmont Mines - Wasamac ? Mine Arnaud ? Managem

Aug 1, 2013

By J. van Huyssteen, M. Cantor

Newmont Ghana Gold Limited's Ahafo Operation has matured from its project ramp up stage into steady state operations after three years of operation. Management focus has shifted from addressing construction and commissioning problems to optimization and improvement. This focus change has coincided with the introduction by Newmont of a Continuous Improvement (CI) program across the company which provided a project management methodology that can be used in the execution of smaller scale projects. This paper focuses on the application of CI principles at the Ahafo Plant through the discussion of several case studies that demonstrate how these principles are applied.

Jan 1, 2011

By Martin Murenbeeld

Outlook: Nine Bullish Arguments 1. Global fiscal and monetary reflation: PIIGS, US, etc. 2. Global imbalances: the dollar must decline 3. Global FX reserves are ?excessive?: diversification 4. Central bank attitudes to gold: now positive 5. Gold is not in a bubble: room to rise 6. Mine supply is flat: ?peak? gold? 7. Investment demand: long-run uptrend 8. Commodity price cycle: many years to run 9. Geopolitical environment: positive

May 1, 2010

By M. Arvola, A. Mäkinen, N. Isomäki

Arsenic is a compound that has no significant market value. However, it needs to be removed from ores, concentrates and other process streams because of environmental or technical processing concerns. A wide range of arsenic containing minerals exists in nature, and in many instances these minerals are also associated with the ones that have commercial value. For example, sulfide copper ores are normally closely associated with minerals like enargite, Cu3AsS4 and tennantite Cu12As4S13. After mineral processing these arsenic sources can report to the waste waters and these effluents need to be treated before discharge or recycling. Ferric arsenate precipitation is a well-established method for stabilizing arsenic in effluents. Electrochemical arsenic removal utilizes the same adsorption/precipitation ideology as ferric arsenate precipitation. Electrochemical arsenic removal, even though it is a simple process in terms of equipment, is a complex system involving chemical and physical mechanisms taking place simultaneously to remove dissolved and/or solid arsenic components from wastewaters. The whole process can be described by the following three steps: 1) electrolytic oxidation at a sacrificial anode (dissolving electrode metal, iron for example), 2) chemical reaction between dissolved iron and arsenic to form a solid precipitate and 3) aggregation of the particles to form flocs, which can be removed by known solid/liquid separation methods. Electrochemical arsenic removal is a very efficient way to remove arsenic from different waters to very low residual concentrations.

Jan 1, 2016