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By A. A. McCloskey

APPROXIMA TEL Y 95 percent of Waite-Amulet's Lower A orebody will be mined by diamond-drill stoping. This method of stoping was developed, and has been successfully applied, at the Noranda mine in recent years(1) and is now used in several base-metal and gold mines in north-western Quebec and in other parts of Canada, South Africa, and Australia. The purpose of this paper is to deal with the features of the Lower A ore-body which led' to the adoption of this method of stoping, and in addition to give a general description of stope layout, stope development, main haulage development, chutes and grizzlies, diamond drilling for stope blasting, diamond drilling and equipment, primary blasting, secondary blasting, haulage and loading, ore pockets, pumping and drainage,. and shafts at Waite Amulet. Figure 1 is an isometric projection of the orebody, illustrating the mining system. The factors that led to the adoption of diamond-drill stoping of Lower A orebody are as follows: (1) Safety.0 (2) Size and shape of the orebody, and depth of the orebody below surface. (3) Strength of the hanging-wall, footwall, and sulphide ore. (4) Continuous ring-drilling from sub-level drifts, with no delay for blasting. (5) Large-tonnage blasts at the end of Saturday afternoon shift, after ali men are out of the mine. (6) Sub-levels may be retreated from top to bottom simultaneously, or lower sub-levels may be retreated first without any change in the ring-drilling la yout. (7) Large stopes up to 100 feet wide can be mined, leaving substantial pillars up to 60 feet in width, which may be partially recovered by âiamond~drill stoping or by other stoping methods. (8) A large tonnage may be drilled-off in advance of blasting, but only a supply of unoxidized ore for flotation treatment is blasted. (9) Better ventilation during working shifts. (10) Gravity flow of all broken ore to grizzlies located in the footwall of the orebody. (11) Electric blasting by a crew of two men.

Jan 1, 1941

By E. P. Williams

"Prince Edward Island, Canada's smallest Maritime Province, is located in the southwestern part of the Gulf of St. Lawrence. The Province is more or less centrally located in the Maritimes Basin, a large intermontane basin within the Appalachian orogenic belt. The Maritimes Basin is subdivided into sub-basins and uplifts which exhibit two dominant structural trends: east and northeast. The Basin is known to be petroliferous because of the seeps, shows, oil shales and albertite found in southern New Brunswick and northern Nova Scotia and the gas and oil produced from the Stony Creek field near Moncton, New Brunswick.Permian beds are exposed on the Island, mostly along sea-cliffs. A maximum thickness of about 5,000 feet of red beds -shales, sandstones and conglomerates -make up the sequence. Over most of the Island, the Permian section is much thinner. Four key wells (Mississippian tests) and several shallower tests have been drilled. The Pennsylvanian-Mississippian section thickens rapidly off the Port Hill Uplift at the northwest, where it is less than 4,600 feet thick, and continues to thicken to about 20,000 feet in the Cumberland Basin at the southeast. Geological and geophysical data combine to give us the structural picture of the deeper beds.Prospective reservoir rocks are primarily in the Missis-sippian Horton and Windsor groups. Prospects are:-1. on or over structural highs in the basement; 2. on anticlines or fault highs; 3. over or peripheral to salt domes or salt-core anticlines; 4. at truncation pinchouts of Mississippian prospective beds; 5. in basal sandstone or granite wash on the pre-Carboni-ferous basement; and 6. in facies traps at changes from sandstone to shale or porous to tight carbonate rocks."

Jan 1, 1967

By W R. Honeywell

Two series of laboratory flotation tests were carried out to study the treatment of Faraday ore by two-stage flotation. First the acid-consumers and then the uranium minerals were floated. On ore ground in the Faraday mill grinding circuit, and using Faraday mill water in the flotation step, a recovery in the flotation concentrate of from 91 to 93 percent of the uranium was obtained in 45 to 50 per cent of the weight at a grade of 0.24 per cent U30s. The saving of acid in leaching the uranium-bearing flotation concentrate, as compared to leaching the whole ore, ranged from 30 to 46 per cent. The average over-all extraction resulting from flotation and leaching of the flotation concentrate was 88.1 per cent. The best collector for the acid-consumers was sodium oleate. Acintol F A-1 emulsion was the best collector for the uranium minerals, and, in the uranium flotation step, an acid pH in the slurry was found to be necessary. The reagent costs were estimated to be 22 to 26 cents per ton of ore.

Jan 1, 1963

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened some time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too ex pensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By A. G. Roach

HISTORY AND LOCATION SEAL HARBOR GOLD MINES, LIMITED, was incorporated in January, 1934, to take over 116 acres of mining lands in the Stormont gold district, Guysboro county, Nova Scotia. The nearby ten-stamp Mulgrave mill was also purchased, and since that time 974 acres of adjoining properties have been secured from the Government by direct lease. The property is served by a motor road and is about two miles from the village of Goldboro, situated on the shore of Isaac's harbour. The bulk of ?the supplies are brought in by coastal steamer from Halifax, a distance of about 100 miles, since the nearest railway connections are at Antigonish, some 40 miles distant. EARLYY WORK The Seal Harbor properties include the old Partington and Beaver Hat mines. A small tonnage of ore was mined from each and treated on the properties in stamp mills, which were later torn. down . A survey of old records shows that this ore averaged about $8.00 gold per ton. Development work by the present Company was confined to the 100-foot level until February, 1935, but after that rime the incline shaft was deepened to 425 feet and the 300-foot level was explored east and west of the shaft. Six belts of ore were intersected to the west of the shaft. The ore from these belts was hand sorted and the ore portion was put through the 10-stamp Mulgrave mill to defray operating expenses and to serve as a sample of the deposits. The average recovery per ton from this sorted ore was $6.10. Samples of the ore were sent to the testing laboratories of the Mines Branch, at Ottawa, and of Canadian Industries, Limited, at Toronto. Recommendations from both of these authorities were for removal of the coarse gold by concentration and barrel amalgamation, followed by cyanidation of the residue.

Jan 1, 1937

By D. M. May

"Cut-and-fill mining is a stoping method that has been widely utilized in the mining industry over the past forty years. It took preference over shrinkage methods at Levack in the early 1930sbecause of its safety aspects; i.e., prompt support of the stope sidewalls, good working floors and better accessibility to support poor back areas. In addition, higher recoveries of ore were possible because of the flexibility of the method in that silling could take place easily at any horizon; low-grade ore could be sorted and left in the stope as fill and certain zones of rock could be left unmined. With modern techniques, a steady production rate can be established, as filling and mining can be carried out stimultaneously.AIthough there are numerous variations of cut-and-fill mining throughout the world, this paper reviews the original type of mining, with modifications and improvements through the years to present modern practices, with the Levack West operation appearing to be the most productive at this time. Stoping efficiencies have also increased substantially from the original 10 tons per manshift to the present 55 tons per manshift.The paper also outlines the many improvements that have been made with respect to mucking and ground support operations; from hand mucking in a single stope to the use of frontend loaders and haulage trucks in fully accessible stope complexes; and from timber props to roof bolts of various types. Although present methods are extremely satisfactory, experimentation is continually being conducted to improve safety and productivity for future mining.IntroductionThe major mining operations of the Ontario Division of Inco Limited are located in the Sudbury Basin (Fig. 1). Around the rim of this geological formation and within 30 miles of the City of Sudbury are nine producing mines and one ' open pit operated by the company .Ore production currently approximates 11.5 million tons per annum from underground and open-pit operations. Underground mining methods include sub-level caving, shrinkage, cut and fill, undercut and fill, blasthole and vertical retreat. The Levack Complex, the main plant of which is the central Levack Mine, produces 11,000 tons per day.The first prospecting in the Levack area, in 1887, was conducted by James Stobie, who examined rock cuts along the route of the Canadian Pacific Railway to the northwest of Sudbury. However, it wasn't until 1913 that operations commenced at Levack under the Mond Nickel Company."

Jan 1, 1981

By J. M. Réjean Gagnon

"Quebec Cartier Mining Company is currently mining a low-grade iron ore deposit in northeastern Quebec. The Company is producing some 8,000,000 dry gross tons of concentrates per year, grading about 66 per cent iron. The pit, which is located on the keel or hinge line of a fold, will eventually be about 1,000 feet deep with a surface area of 8,000 by 2,600 feet. The most significant structural discontinuities in the mine are the natural bedding planes and secondary perpendicular joints. The exposed walls are subjected to a sub-Arctic climate and heavy blasting occurs approximately six times a month.QCM utilizes design and operating techniques to control rock fall. Steps are also being taken to analyze the ultimate over-all pit slope stability."

Jan 1, 1968

By C. T. Bischoff

Introduction Air conditioning is a term which has come into common use only during our generation. By definition, it means the positive and accurate control of temperature, humidity, movement, purity, and component constituents of the atmosphere within an enclosure. Claiming such results for Noranda's ventilation system, or for that of any other large mine, at present would be an idle boast. However, we are working toward that end with considerable success. Modern underground ventilation at Noranda dates back about six years. The later development of air conditioning is in its fourth season, but still in the experimental stage. Various ingenious methods have been devised to cool mines which, because of climatic or geological conditions or depth, are excessively warm. A few installations have been made to warm intake air during the winter months where this is necessary. However, the method currently in use at Noranda is unique in that it accomplishes both ends by one process. This method utilizes the freezing and melting of ice to equalize year-round temperatures. Mining Methods While a discussion of mining methods at Noranda is not proposed in this paper, a brief summary may be in order. The Horne mine of Noranda Mines, Limited, has been developed by six shafts, four of which are now active. The most recent, an internal shaft, extends to 6,000 feet below surface, but all of the ore mined to date has come from above the 3,000-foot level. Figure 1 shows a model of principal ore bodies. The area mined is relatively small in plan, considering its vertical extent and the tonnage per vertical foot. Most of the ore lies within an ellipse about 600 by 1,000 feet. While this has certain advantages, the mining of such massive orebodies has presented many problems.

Jan 1, 1947

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

By K. C. Grogan

"GeneralGIANT ORE is complex, with the gold values for the most part occurring in extremely close association with arsenopyrite, stibnite, jamesonite, and a wide group of antimonial minerals locally termed 'the grey minerals'. Pyrite is the most abundant of the sulphide minerals• and minor quantities of chalcopyrite, galena, and sphalerite also occur. Pyrrhotite has been found in some sections of the mine, but to date none of it has been nickeliferous. Native gold occurs in varying amounts throughout the ore bodies.In 1944, ore dressing investigations were commenced on diamond-drill core rejects and samples of surface outcrop ore. Results soon indicated that treatment to produce satisfactory recovery of the gold values would involve fine grinding to 80-85 per cent minus 200 mesh, recovery of free gold by jigs, followed by flotation, roasting of the flotation concentrate, and subsequent cyanidation of the calcine. Proceeding from this information, the flow-sheet was prepared, plant design worked out, equipment purchased, and construction of the treatment plant commenced in May, 1947.The crushing, grinding, and flotation units of the plant were rushed to completion and commenced operation on May 12th, l.948, at 225 tons of ore per day. This rate was maintained until January 27th, 1949, when the Allis-Chalmers roaster and cyanide plants were completed and commenced operation. During the period May 12th, 1948, to January 27th, 1949, gold recovered by amalgamation was the sole source of revenue. Flotation concentrate was stockpiled pending the completion of the Allis~Chalmers roaster and cyanide plants."

Jan 1, 1953

By Corrie Pitzer

Safety performance in many companies and even industries has stalled in the few years. Accidents rates are at a ?plateau? and yet, serious accidents and fatality rates are not. In more dramatic cases, such as in the BP Texas disaster, organizations that have ?exemplary? safety statistics, suddenly have a catastrophic or multi-fatality event occurring. Other classic examples are the Piper Alpha disaster and NASA?s Challenger and Columbia disasters and even the Chernobyl nuclear reactor. Looking into the root causes of these accidents provides an insight into the events and deficiencies that led up to the accident, but what are the common features in the organization?s mindset? What characterizes these organizations? decision making, their approach to safety and to risk and are there specific cultural features that can be delineated? The research and review presented in this paper covers a period since 1994, which started in the Australian resource industry and since then covered international events. The features of these organizations are summarized as the seven deadly delusions, based on extensive research since 1997 of organizations that suffered unexpected disasters. Their huge focus on safety, the achievement of lofty goals and celebration of safety successes led to ?mindset? that they are leaders in safety, protected by an extraordinary safety system and that their safety incident figures indicated a truly world-class safety performance. It led them into the trap of the seven deadly delusions?

May 1, 2011

By A. K. Ratte, C. M. Brown

"IntroductionIn autogenous mills, grinding of the ore feed is accomplished by the direct action of the variously sized rocks making up the feed on each other and the mill interior. Size reduction is achieved without the addition of grinding media foreign to the mill feed, differing in this respect from rod, ball, and pebble milling. The term ""semi-autogenous"" has entered common usage in the industry to describe autogenous mills to which supplementary grinding ball additions are made to increase the rate at which size reduction of the mill feed occurs, beyond that achieved solely by the action of rock on rock. In a semi-autogenous grinding (SAG) mill, 50Jo to 10% of the mill volume may be occupied by grinding balls, whereas a range of 25% to 45% is more usual in ball milling.The comminution of mineral ores using ""conventional"" techniques has been described in previous papers. In conventional operations, size reduction of mined ore, and liberation of the valuable mineral content, is typically accomplished using flowsheets employing two to four stages of crushing. Crushing is followed by one to three stages of grinding and classification using various combinations of rod, ball, and pebble mills. This paper describes operations employing autogenous or semiautogenous grinding as the principal stage in the comminution process. Primary crusher discharge, or in some instances run of mine ore, is fed directly to an autogenous or semi-autogenous grinding circuit. Final product sizing may be accomplished in a single grinding stage, the mills operating in closed circuit with classification equipment, or in several stages using autogenous and semi-autogenous mills for primary grinding, and ball or pebble mills for secondary grinding. In several operations a portion of the primary mill discharge is crushed in an intermediate comminution step, these circuits being called autogenousball- crusher circuits (ABC). Many different flowsheets exist, but common and important to most are crushed ore stockpiles, reclaim feeder and mill feed conveyor systems, pumps, screens, and classifiers. Autogenous grinding is employed in both wet and dry processes, although today wet predominate."

Jan 1, 1989

By W. T. Robson

LAKE Shore Mines, Limited, with property at Kirkland. Lake, Ontario, was incorporated m 1914 and commenced product10n m March, 1918, with an initial capacity of about 60 tons per day. Since that time a gradual expansion has taken place until a present capacity of approximately 2,300 tons per day has been reached, giving a total annual gold production valued at approximately $16,000,000. At the time of incorporation of the Company, the Lake Shore property consisted of four mineral claims and four fractions, totalling 171.05 acres. In 1934, four claims belonging to the Minaker Kirkland Gold Mines, Limited, were acquired and a controlling interest purchased in the Kirkland Hudson Bay Gold Mines, Limited. Both these properties adjoin the Lake Shore claims on the south. From the accompanying compilation of the world's largest gold mines for 1934 (1), it will be seen that, while Lake Shore holds sixth position in respect to the number of ounces produced, there are twenty-five gold mines which treat a greater tonnage of ore. This is an indication of probably the most unusual feature of the Kirkland Lake deposits, namely, the high aver-age tenor of the ores. coupled with the comparatively large tonnages available.

Jan 1, 1936

By R. L. Dunsmore

Introduction If one had been called upon to describe petroleum oil refining seventy-five years ago, he could have acceded to the request quite satisfactorily in about fifteen minutes. Fifteen years ago, an hour and a half would have been sufficient to give a general idea of oil refining, and of the equipment used for this purpose. Today, so extensive has been the research into all phases of the refining and manufacturing of petroleum products, and so rapid the strides in improvement in technique and equipment, that I doubt if a week would suffice to give an adequate outline of ail the ramifications of present-day oil refining. I propose to only 'hit the high spots', dealing particularly with the equipment and methods employed at the Imperoyal refinery, which you are to visit. Crude oil, the refiner's raw material, contains essentially only two elements, hydrogen and carbon. These are not present in the free state but are combined in various proportions as 'hydrocarbons'. A given crude oil is not made up of just one hydrocarbon, but of myriads; some solid, others liquid, and still others gaseous at atmospheric temperature and pressure, ail dissolved one in the other. Moreover, the nature and the relative amounts of the several hydrocarbons vary very considerably in crude oils from different sources. That is, a 'crude' from Oklahoma will contain hydrocarbons not present in crude from Mexico, and is different again from the Venezuela crude. Not only this but oil in a certain well in, say, Peru may be differently constituted from that in a well half a mile distant from it.

Jan 1, 1931

By E. LaRocque

"Denison Mines Limited has been processing uranium ore in the Elliot Lake area since May of 1957. The ore body is located i11 the Huronion sediments on the north limb of the Quirke Lake syncline. Minerals of metallurgical significance are brannerite, uraninite and monazite. Gangue minerals include quartz, chlorite, sericite, pyrite, pyrrhotite and rutile. Silica content of the ore is greater than 75 % and pyrite-pyrrhotite content around 7 %. Specific gravity of the ore is 2.75.The Denison flowsheet is based on sulphuric acid leaching to extract the uranium values from the ore followed by liquid-solid separation to wash the uranium-bearing solution from the barren ore. The resultant pregnant solution is concentrated and purified by ion exchange followed by two-stage precipitation with ammonia to produce an ammonium yellow-cake.Elliot Lake ores require high acid concentrations and high temperatures to extract the uranium from brannerite and monazite. Uraninite will leach at low acid concentrations as long as oxiclizing conditions exist. The whole ore must be treated so that these conditions do exist.This paper provides a description of the leaching process equipment as originally installed and major changes in that equipment to date. Process control refinements to economically improve extraction are also discussed."

Jan 1, 1979

By S. R. Gilbert, C. O. Bounds, R. R. Ice

"Many ores are upgraded to produce auriferous sulphide concentrates (principally pyrite) which are not amenable to direct cyanidation. Often these refractory gold-bearing concentrates contain undesirable elements such as arsenic, antimony, etc., which present environmental and/or processing problems. The pretreatment techniques most often considered for processing these concentrates prior to cyanidation include roasting, pressure oxidation, chemical oxidation, pre-aeration, and recently, bacterial oxidation. In this paper, the technical performance and economics of bacterial pre-oxidation vs the classical roasting approach for treating a specific auriferous pyrite concentrate are compared. The results provide flow sheets, preliminary operating and capital cost estimates, and rates of return for the two processes and demonstrate the potential advantages of bacterial pre-oxidation. IntroductionThe increased attention that gold has received in the last ten years has prompted mining companies to look for lower grade orebodies. Many of these low-grade ores do not respond well to conventional direct cyanidation recovery techniques. As free-milling ores decline, gold is sought in refractory environments which, ultimately, drive up the treatment costs.There are a number of reasons for a gold ore to be termed refractory, most of which can be identified by thorough mineralogical examination. The mineralogical occurrence of gold can, to a great extent, impact the method by which the ore is treated and, consequently, the capital and operating costs. Gold in a refractory ore can often occur as discrete particles locked in a host of silicate or carbonate gangue, or associated with sulphides or sulphosalts. Depending on its particle size, gold can be liberated and recovered by mechanical size reduction such as regrinding. This approach is most effective for gold in the 10 - 50 micron range. Gold can also be associated with clay, iron hydroxides, or other minerals which tend to coat the gold surface and inhibit the penetration of the cyanide solution, resulting in poor plant recovery. Because of their resistance to cyanide dissolution, gold tellurides and other refractory gold minerals are also responsible for losses to the tailings. For these reasons, it is paramount that the mineralogical occurrence of the gold be thoroughly and accurately determined before selecting a final process flowsheet."

Jan 1, 1988

By W. C. Whittaker

"This paper gives a brief resume of the changes in the market picture for Western coal since 1948. It then analyzes present markets and recent developments in Western Canada, the western United States and Japan, and forecasts future markets in these areas to 1975.INTRODUCTIONCOAL HAS BEEN MUCH IN THE NEWS OF LATE, both in the United States and in Canada. In the United States, this is because of the booming condition of the industry and because of the purchase of control of a number of America's largest coal producers by the integrated oil and metal producing companies seeking additional fossil fuel reserves and diversification. In this regard, it is interesting to note that ownership of America's largest strip coal producer was recently acquired by one of the world's largest copper mining companies. In Canada, the conclusion of several large-scale, long-term contracts for the sale of coal to the Japan Steel Group and the projected use of Canadian coal in steel mills in the western United States has focused much attention on the coal industry."

Jan 1, 1968

By Shintaro Takamiya, Kazunari Yoshida

"Recently, small sized micro-needles for medical are required more frequently by patients. The biggest reason is that it presents great burden on the patients, due to the size of the needle injection. People need to use a very small needle to lower the pain, but the downfall is that it makes them more expensive due to their complicated manufacturing method. Therefore, we need to fabricate a needle by wire-drawing to decrease its price. Tube-drawing is beneficial for its production value; however, in conventional tube-drawing it is difficult of control the wall thickness of the tube and makes it 1mmor lower in diameter. That is why, we propose fluid-mandrel drawing for new tube drawing. This method allows fabrication of a fine tube by using the pressure of the fluid in the tube. In this research, the goal is the fabrication of a fine tube by fluid-mandrel drawing and its evaluation. Finally, the fabrication of a fine tube by fluid-mandrel drawing was conducted and in result a tube with a diameter of 0.2mm, high strength and thin wall and fine inner surface was drawn, which can be used as a lesser pain micro-needle.INTRODUCTIONThe main manufacturing method of the current medical needles is roll forming. With this method, it is difficult to make a tube with a diameter lower than 1mm. Deep drawing has been proposed and used as method to further reduce the diameter, but this method is costly and the injection needle obtained by this method is several times more expensive.Therefore, we need to obtain a fine medical needle by drawing process that can be mass-produced and inexpensively manufactured. However, with the conventional drawing process, it is not possible to obtain a syringe needle with a reduced diameter easily, that is why, a fluid-mandrel drawing has been proposed which can reduce the diameter without damaging the inner surface. The methodology of the method is, a fluid is filled in the sealed tube and the pressure inside the tube during drawing is responsible for the good inner surface and wall thickness. It is also expected that the fluid can be easily discarded and that the tube can be manufactured on a long scale."

Jan 1, 2017

By Julien Rivard

Au printemps 2011, la Corporation minière Osisko met en production le gisement Canadian Malartic, qui devient la plus importante mine d?or à ciel ouvert au Canada. Pour lui faire place, elle a déménagé un quartier de 205 maisons et construit 6 nouveaux bâtiments institutionnels. Les démarches ont commencé en 2006. La compagnie a d?abord établi l?emplacement du nouveau quartier résidentiel, en collaboration avec la Ville de Malartic, puis fait la conception de ce quartier de manière à refléter au mieux les caractéristiques du quartier à déménager. Elle a ensuite effectué une opération d?assignation consistant à proposer à chaque propriétaire intéressé un lot dans le nouveau quartier. Au total, 140 résidences ont été déménagées en 2008 et 2009 et 65 été rachetées par la compagnie, le tout par des ententes de gré à gré sauf pour un seul cas. La réussite d?une opération d?une telle importance sociale n?a été possible que parce que la compagnie s?est assurée d?un soutien massif de la population et des autorités pendant tout le processus. Cette expérience peut être fort utile pour les nombreux projets miniers dont l?insertion dans la communauté est un enjeu important.

May 1, 2011

By B. Erdem, N. Çelebi

An important problem associated with tandem dragline systems is that of matching the productive capability of individual draglines in the combination. In this paper, a dependence mechanism among draglines in a tandem system is described, and possible consequential problems in a poorly-matched system are defined. The rate of linear advance and the cost of stripping are determined as two major indications for an efficient operation. The proposed decision criteria and the underlying mechanism to select a synchronous couple are introduced and used in simulating tandem dragline systems. The developed model is tested on a hypothetical strip mine where pullback stripping is applied with a tandem dragline system.

Jan 1, 1999