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By J. Guha, A. Gobeil, P. Pilote, A. Tremblay, E. Dimroth

The Mount Bourbeau Lac Berrigan area is located just to the north of the Town of Chibougamau. The axial trace of the Chibougamau syncline borders the northern part of both areas. The area contains Archean rocks of the Roy Group, intruded by the Cummings Complex and the Line Lake tonalite stock. Proterozoic sedimentary rocks occur in a series of outliers. Various Cu, Zn, Pb, Ag, Au and Mo showings are dispersed over the area in a wide range of time and space. Pre-Kenoran (stratiform and stringer) showings related to volcanic activity may be distinguished as well as the syn-or post-Kenoran (vein) types whose nature is imprecisely known. In this area, the stratiform showings occur in the Gilman and Blondeau Formations, whereas the vein type showings occur for the most part in fractures or breccias within or along the contacts of the various sills of the Cummings Complex. Mount Bourbeau is distinguished by the greatest variety of showings as well as the proximal volcanic facies of the Blondeau Formation. A volcanic centre is presumed to lie a short distance north or east of the locality. Locally, the Line Lake stock contains significant silver, molybdenum and gold mineralization. Its role as a metal reservoir, a source of heat for the circulation of hydrothermal fluids and its control of the local tectonic style remains to be determined.

Jan 1, 1984

By Dwight Newman

This paper discusses the author?s work identifying international law norms of consultation with indigenous communities and poses a potentially counterintuitive argument that corporate stakeholders? interactions with indigenous communities may have effects on the content of those norms. The claim is counterintuitive because the international law of pertinence is customary international law, which arises from consistent state practice and opinio juris (a belief by states that they are acting in a way they are legally bound to do so). Customary international law traditionally has no reference to corporate conduct per se. The paper first surveys several sources on developing international law on consultation obligations. Then it references the impact these norms can have on corporate stakeholders in industries like mining. Then, it poses an argument as to an economic ratcheting effect that can occur through various agreements between corporate stakeholders and indigenous communities that then feeds through into international law via several mechanisms. The consequences for mining companies are diverse and include the possibility that conduct by one company can have longer-term implications for the obligations of other companies and, indeed, of states. The effects will differ in the context of different competitive environments and may actually have effects on the economics of different competitive models.

Aug 1, 2013

By F. Chiesa

The permanent mould process, which is a favoured process for producing premium quality aluminium casting, is rarely used to produce magnesium alloy parts. This may be attributed different factors such as: the reservation with which the automotive industry considers using magnesium in structural castings; also the relative hot shortness of most magnesium alloys when compared to aluminium A356/357 is another factor. A third reason stems from the fact that the "heat content" of magnesium is much less than that of aluminium, resulting in the difficulty, for a relatively slow process such as permanent mould (versus pressure die casting), to reach a mould dynamic equilibrium temperature sufficiently high to avoid premature freezing and misruns. The present work will address this problem by carrying out controlled cycling of a laboratory mould, poured with aluminium and magnesium alloys. The influence of insulation of the mould and artificial electric heating on the run-in mould temperature will be determined experimentally. A thermal model will be sought for these thermal devices that will allow to predict the thermal behaviour of moulds of different geometry before a single casting is poured. The model will be tested on an industrial casting in a workshop environment.

Jan 1, 2006

By Alice H. Zhu

Belt conveyors are widely used in materials handling industries. The bulk materials which can be transported include ores, coal, earth, grain, limestone, wood chips, fertilizer components such as potash and many others. Along with the new technology development and enhanced industrial automation requirements, belt conveyor instrumentation has also been modernized to improve conveyor availability and performance. Traditionally, belt conveyors are equipped with emergency pull cord switches to shut the conveyor down, misalignment switches to signal the belt offline condition, speed sensors to detect the belt slippage, and level switches to prevent material plugging in the discharge chute. Belt rip detectors are also normally provided for long belt conveyors. As a rule, equipment condition monitoring is not automated at most operating facilities, but is performed manually by maintenance staff via time-based surveillance. The new generation of condition monitoring instrumentation and control equipment can be successfully utilized to design a reliable, cost-effective, and centralized monitoring system, capable of monitoring a wide variety of mechanical equipment. The implementation of the condition monitoring automated system can provide continual monitoring of the plant equipment to ensure safe operation of the equipment to its required capacity. Any abnormal behavior of the motors, gear reducers and pulleys can be analyzed, alarmed, and recorded immediately, so problems can be detected and resolved before critical components failure. Therefore, the current trend is to provide the belt conveyors with condition monitoring system in addition to the traditional instrumentation, where temperature probes and vibration sensors can be installed on motors, gear reducers and all pulleys. Another innovative development is a three-in-one type belt rip detector which combines laser, tray and cord type detection together to ensure a prompt belt tear indication. The purpose of this paper is to present the latest development of belt conveyor instrumentation and introduce the application of newly developed instruments.

Nov 1, 2011

By P. H. Oliver

"The current theory of how explosives fracture rock offers no explanation for the improvements in fragmentation and the reduction of fly rock and back break which occurs when an adequate inter-row delay time is used. Nor does it explain why fragmentation improves with rectangular drill patterns where the hole spacing may be as much as four times the hole burden.A new theory of rock fragmentation is proposed which builds on the existing theory. It offers rational explanations for the many blast effects which the current theory does not address and the need for adequate timing delays between rows. It improves on the design of inter-row delay timing by defining the length of free-blasted face needed in front of a hole *Retired from Inco Ltd., Sudbury, Ontario when selecting the delay element which will provide an adequate inter-row delay time."

Jan 1, 2003

By P. H. Oliver

The current theory of how explosives fracture rock offers no explanation for the improvements in fragmentation and the reduction of fly rock and back break which occurs when an adequate inter-row delay time is used. Nor does it explain why fragmentation improves with rectangular drill patterns where the hole spacing may be as much as four times the hole burden. A new theory of rock fragmentation is proposed which builds on the existing theory. It offers rational explanations for the many blast effects which the current theory does not address and the need for adequate timing delays between rows. It improves on the design of inter-row delay timing by defining the length of free-blasted face needed in front of a hole when selecting the delay element which will provide an adequate inter-row delay time.

May 1, 2003

By L. M. Gould

"Syncrude Canada operates the largest oil sands crude oil production facility in the world and produces over 13% of Canada’s total oil requirements. To achieve this, Syncrude mines the oil sands in open pits, extracts the raw oil known as bitumen from the sand using water-based processes and upgrades it into sweet light crude oil by fluid coking, hydroprocessing, hydrotreating and reblending. The final product, Syncrude Sweet Blend (SSB), is sent by pipeline to three Edmonton area refineries and then to pipeline terminals which ship the SSB to refineries in Canada and the United States.As parts of the Mildred Lake base mine reached their economic life, they were replaced with new facilities at the Aurora Satellite mine. Aurora is situated on Oilsand Leases 10, 12 and 34, 35 km northeast of the Mildred Lake facility (Fig. 1).In 2000, the first hydrotransport low-energy extraction production train started up at Aurora. A second production train is scheduled for start-up in 2003. Open pit mining at Aurora occurs using two hydraulic shovels, two cable shovels, and trucks ranging from 320-ton to 380-ton payload capacities (Fig. 2).Once the oil sands is excavated, the trucks dump the ore into a crusher designed to break up the big lumps of oil sands and rock at peak rates of 11 000 t/hr. The ore is then transferred by conveyor to a surge pile and then to a mixing box which combines the oil sands with hot water. Following bitumen separation in the primary separation vessel, froth is delivered to Mildred Lake for processing via the intersite pipeline (Fig. 3).The goal of this paper is to illustrate how high precision shovel GPS (HPGPS) is being used at the Aurora mine to aid in mine planning. This can be accomplished by first describing the function of the mine planning department, describing the Aurora orebody, and finally explaining how the HPGPS system functions and how it is employed at Aurora.The short range mine planning department ensures a steady supply of ore is delivered to the plant at the desired grade in a sequenced and economical manner. This is done by creating a mine plan that consists of shovel dig locations that require the shovels to mine in a specified area at a specified elevation."

Jan 1, 2002

Ground support audits are sometimes necessary in ageing underground mines. Usually, the purpose of such audits is to assess the state of the ground support in various parts of the mine, identify areas that require attention and establish rehabilitation requirements. In 2005, Brunswick Mine, located in Bathurst, New Brunswick, Canada, completed a comprehensive mine-wide ground support audit. The areas examined included excavations in several mining blocks, as well as ramps, shaft stations, garages, shops, etc., throughout the mine. A vast amount of data was collected over a period of two weeks by multiple auditing teams. The audit was followed by a data digitisation exercise, and the creation of a data management system to store audit results and keep track of subsequent rehabilitation activities as they occur. One aspect of the data management system was the incorporation of a function for reporting on ground rehabilitation progress, along with the capability of updating mine level plans for easy visual presentation of this progress. This article describes the approach implemented at the mine to carry-out the audit, as well as the database constructed to manage the results.

May 1, 2009

By Aleksandar D. Bugarski

Despite extensive research efforts conducted in the past decades, occupational health risks associated with exposure to nano and ultrafine aerosols emitted by diesel power equipment are still not completely understood. The complexity of physical and chemical properties of diesel aerosols, constantly changing with the implementation of advanced diesel emissions control technologies, make this task rather challenging. The objective of this paper is to identify and characterize nanometer and ultrafine aerosols emitted by diesel engines in the underground environment and evaluate the effects of selected contemporary control technologies on physical properties, chemical composition, and in-vitro toxicology of diesel aerosols. The physical and chemical properties of the nanometer and ultrafine diesel aerosols are to be characterized through a test series in the NIOSH Lake Lynn Laboratory experimental mine. The crucial part of the study has been development of a facility that allows researchers to generate field results with precision and accuracy characteristics of a laboratory environment. The knowledge obtained from this study should strengthen our understanding of the health implications related to exposure to diesel particulate matter and aid in assessing the potential of various control technologies for reducing this exposure.

May 1, 2007

By J. E. Ryan

General Description Due to the extreme cold weather experienced in Flin Flon during the winter months, thought and precaution were necessary in the design of the plant buildings. The machine shop, carpenter shop, drill shop, and coal plant buildings are similar in the building materials used in their construction. They are sided with two-inch shiplap, insulated with celotex and asbestos paper, and covered with corrugated iron on all side-walls. Roofing consists of 2 by 4 lumber on edge, laminated, and further covered by celotex and three-ply roofing. These buildings are heated by means of unit heaters. The heaters are primarily steam-heated radiators, through which the air of the buildings is circulated by electrically-driven fans. Our machine shop is located to the east of, but central to, the main operating buildings of the mine and plant, and is so connected by a net work of tracks as to be able to serve all portions of the entire plant conveniently. The building is divided into two bays, the main bay 53 ft. by 340 ft., and the east bay 24 ft. by 340 ft. The shop office and drafting room, a two-story annex 24 ft. by 30 ft., is located on the west side of the shop. The arrangement within the shop is such as to house conveniently the several departments, namely, heavy machine tool section, repair floor section, boiler shop heavy tool and floor section, blacksmith heavy tool and forge section, tool room, electric welding rooms, stock room, tin and copper shop, and electrical parts and armature winding and repair shop (see Figure 1). All the heavy tools, the repair floor section, and railway tracks are so located in the large open bay as to be fully serviced by an electrically operated 15-ton bridge crane, with a span of 50 feet and a travel the full length of the shop. A standard-gauge railway track, branched off the main line, penetrates the full depth of the building. This track lies along the extreme east side of the main bay, allowing easy entrance and movement of rolling stock and heavy machinery, loaded on standard flat-cars, to the repair floors in the main bay. Eight jib cranes, affixed to building columns, further facilitate the heavy repair work throughout the various shop divisions. Our light and heavy machine tools are standard equipment, not unlike tools used in mine, mill, and railway shops.

Jan 1, 1935

By Matthew P. Wickham

The use of existing mine records in conjunction with an appropriate classification scheme can be used successfully to identify and characterize the composition of existing waste rock facilities where traditional approaches based on sampling may be impractical or costly. This paper describes an alternative approach used in an acid rock drainage investigation at a porphyry copper mine with numerous waste rock dumps of varying ages and composition. The approach integrated detailed lithologic and mineralogic information about the ore body and overburden materials with records of pit development and dispatch. A waste rock characterization matrix was developed for the site to meaningfully classify lithology and mineralogic composition of the waste rock. The approach resulted in a focused geochemical testing program and facilitated interpretation and application of the test results.

May 1, 2002

By Richard Poulin

Rehabilitation of mined out areas is often enforced by environmental bonding. It is usually assumed that this process provides financial assurance that rehabilitation will be carried out as agreed at the permitting stage. Shortcomings of the current practice in environmental bonding for mining are reviewed. Of particular importance for the public, for governments and for the environment is the absence of protection against cost overruns and companies defaulting before the bond amount is entirely paid. Elements of solution are identified through the emergence of environmental insurance as a complement to bonding for cost overruns and defaults. A cover of environmental catastrophes could also be added, hence reducing the risk for the public and the environment. We examine the merit of creating a captive insurance company under the responsibility of the mining industry. The use of insurance techniques would incorporate a genuine risk management dimension to the financing of rehabilitation.

May 1, 2004

By Margarete Kalin

"Difficulties arise in implementing environmental technologies in the mining sector because important fundamental processes, which lead to the environmental degradation, are ignored. Weathering rates, the role of bacteria in the process and the incomplete application of the matching principle of accounting at the time the mining disturbance take place. Mining is a multi-stakeholder activity and the environmental problems have multivariate dimensions also effecting process.The limiting factors in the contaminant generation process are the transport of oxygen by advection, convection or diffusion in air or water and the associated microbial activity. Weathering products are transported from the mineral surface by atmospheric precipitation to surface and groundwater. This contamination takes place at different rates, requiring a long time to evaluate technological choices.Restoration efforts have to focus on slow reaction rates in the contaminant generating processes. Technology, which does not address the reaction rates and is selected based on inappropriate time scales, will not provide long-term solutions. Natural approaches to reduce acid generation, based on Ecological Engineering principles have required decades of research and field testing, but now show promise in addressing the cause of AMD and ameliorating its effects."

Jan 1, 2005

By Will Callupe Arzapalo

The success of the minimization of blast induced-damage at Barrick?s Pierina Mine in Peru is the result of an effective working relationship between Mine Operations and the Geotechnical Services Department. A detailed design criteria manual is used to match the blast plan to the site?s varying rock types and slope designs. The Geotechnical Services Department has further developed a comprehensive pre- and post-blast checklist that is critical to the drilling and blasting process as it pertains to wall stability. Wall control blasts are evaluated with quality assurance field checks, vibration monitoring and frequency control, video assisted performance quantification and post excavation face profiling. These detailed observations are compiled and summarized in a blast performance evaluation that is considered to be an ?Industry Best Practice?. The information and detail provided by each performance summary allows accurate blast analysis and effective design refinement.

May 1, 2006

By George C. Coupland

"THE PRELIMINARY EVALUATION of the orebodies was computerized for tonnages and grades on a 20- by 20-ft grid. The evaluation was based on drill-core intersections over 40-ft vertical projections coinciding with the proposed bench intervals, taking the deviations of the drill holes into account. The computer print-outs gave an ore distribution and evaluation bench by bench and indicated the areas of varying mineralization. The two orebodies have a combined length of 2,200 ft. and a maximum width of 600 ft. They strike almost due north, dip about 85 degrees east and rake to the north. The computer print-outs were used to design an open pit with an over-all waste to ore ratio of 2.58:1. At the outset, the waste to ore ratio was 4:1. The pit is tear-drop shaped, with the narrow end to the south, and at the surface is 2,600 ft long by 1,800 ft wide. Ramps are 100 ft wide, with a 10% grade. The south ramp is left-handed, starts at the southeast and will continue to the bottom of the pit. A second ramp on the west and north walls runs from surface to join the south ramp at 7 bench. This ramp will handle the total pit production when part of the south ramp, from 4 bench to surface, is lost due to the underground operation. Over-all wall slopes are 53 degrees, and are laid out to avoid prominent protuberances which could relax and become unstable and potentially dangerous (Fig. 1) ."

Jan 1, 1974

By Alfred Annor

Deep mining requires innovative approaches in ground control technology and the search for new ground support materials including backfill. There is a need to look at mine waste materials that may be available in deep mines to assess their suitability for use as composite backfill. Composite materials are widely used in all areas of engineering because of their unique and often superior structural properties compared to those of the singular constituent materials. Over the past few years, there has been a growing interest towards the investigation and use of various types of composite backfill materials as special applications fill in mines. A research project is being conducted at CANMET- Mining and Mineral Sciences Laboratories, Natural Resources Canada, to investigate the properties of potential ground support materials for use in deep mines. As part of this investigation, composite backfill materials were prepared by combining waste rock aggregates and mill tailings in various ratios, to determine their optimal mix proportions for strength development. A few cemented rockfill and straight tailings paste backfill samples were also prepared and were used as controls for the study. Two sample sizes were used for the investigation in order to evaluate the scale effects on the material behaviour. A set of samples were cured at 44 EC to simulate the anticipated temperature conditions in deep mines. A second set of samples were cured at 23 EC to provide engineering reference data. The test results show that compared to either the cemented rockfill or the straight tailings pastefill material, the composite backfill samples were the strongest and stiffest of all the test materials investigated in this study. The composite backfill samples also produced the lowest void ratio and porosity values compared to the cemented rockfill and the straight tailings backfill material. This paper will present the results of the laboratory investigations to date. It will also outline the on-going work at CANMET - Mining and Mineral Sciences Laboratories to further assess the ground support potential and viability of using composite fills in deep mines.

May 1, 2003

By Chris Cross

A working group from Anglo American, BHP Billiton, Rio Tinto and Xstrata reviewed supply and demand for graduates from mining education departments in countries where they normally recruit: Australia, Canada, Chile, Western Europe, South Africa and USA. Departments are typically small and increasingly unsustainable, resulting in a steady rate of closure. Supply and demand for graduates in the minerals industry is cyclical, with supply lagging behind demand and trending downwards. Currently, supply is tight and the industry is trying to expand with an ageing workforce. Greater collaboration between universities and within the industry is recommended to address these issues.

May 1, 2006

By H D. Smith

T HE production of coal in Canada was slightly higher in 1964 than in the immediate past, and the major users continue to be the electric utility and metallurgical industries. There are continuing trends toward the increased use of cokes and chars in various metallurgical applications. Geological Research During 1964, the coal drilling program of the Research Council of Alberta (RCA) was concentrated in the extreme south of the Province (notably in the Milk River area and the region immediately to the northeast of this area). Field work commenced on June 1 and was completed at the end of September, by which time a total of 376 holes, aggregating some 48,500 ft., were drilled in 132 townships. Although no new major coal occurrences were intersected, the pro-gram yielded useful data for defining the extent of the known coal deposits in the area. Detailed results will be analyzed during the winter and reported in due course. Meanwhile, a full report on the

Jan 1, 1965

By Jehan Rondot, Raymond Marleau

"Des quartzites trés pars ont été découverts au cours de la cartographie de la region du lac des Martres, étape de l'étude géologique de la region de Charlevoix.On distingue quatre groupes métasédimentaires, tons con tenant des niveaux de quartzite dans an mains deux domaines géologique différents, c'est à l'ouest, clans le do¬maine gneisso-charnockitique que se situent les quartzites du groupe des Martres. Quartzite et gneiss à, grenat et sillimanite, en banes épais, constituent la formation de La Galette. A Pest, dans un environnement gneisso-granitique, les deux groupes métasédimentaires de Saint-Siméon, et de La Malbaie comprennent, par contraste, des bancs pen épais et de compositions variées. Les niveaux de quartzite dépassent rarement 50 m d'épaisseur. L'autre groupe métasédimentaires, celui de Saint-Tite des Caps, recoupé de nombreuses intrusions charnockitiques et granitiques, ne possède que de minces niveaux de quartzite.La pureté et la grande épaisseur des quartzites de La Galette suppose une histoire complexe qui se termine par des depots continentaux de climat aride, par opposition aux depots marins des autres groupes. D'autre part, la presence de ces quartzites an sein de roches Presque anhy¬dres et de haute temperature que sont les charnockites leur confére des caractéristiques de fusion sans decrepitation.Parmi la multitude de depots de quartzite qui existe clans le monde, peu sont de qualité supérieure. Or, de par sa composition chimique, le quartzite de La Galette se compare avantageusement à ceux des meilleurs gisements des Etats-Unis, de l'Europe de l'Ouest et de l'Afrique du Sud. D'accès facile pour l'exploitation, les gisements ne sont qu'à une trentaine de milles de Baie Saint-Paul ou de La Malbaie, sur le Saint-Laurent.L'utilisation en metallurgic prévue pour le quartzite de La Galette comprend la production de silicium, de ferro¬silicium et d'autres alliages de silicium. La composition du quartzite est en outre appropriée pour la production de carbure de silicium et de silicate de sodium. Les fines peuvent être utilisées pour la fabrication du verre et comme matiere de charge"

Jan 1, 1977

By M. Pekguleryuz, S. A. Argyropoulos

"The recovery of additions in light metals is an important parameter influencing consistency of the finished product, which ultimately means cost. Recovery is a function of many parameters such as assimilation speed, addition density, addition practice, liquid metal processing conditions, etc. In liquid metal processing operations, it is desirable to have the maximum possible recovery at the shortest possible time.In this paper a new index will be presented, namely, the rate of recovery (RR). This index quantifies the addition recovery and introduces the time dimension in the recovery increase. As such, the RR equips the liquid metal practitioner with an accurate picture of addition assimilation in liquid metals. Results will be presented on how this index is applied to a variety of additions in liquid aluminum. IntroductionThe data on addition assimilation kinetics offer a valuable parameter describing how fast a given addition enters the metal bath. These data may be expressed as gr m-2 s-1 of additive for a set of experimental conditions which might include bath temperature and degree of bath agitation among others. However, the liquid metal processing practitioner is more interested in the recovery of additions. In other words, the point of interest is the percentage of the used addition entering the metal bath. Ideally, the addition recovery can reach the 100% level. However, in practice, the addition recovery never or rarely reaches that level. Many factors can contribute to this. Some of these factors can be slow assimilation kinetics, addition density, addition practice, turbulence of the melt, etc. In some cases, sloppy addition practices can contribute to low recoveries, or even worse, to erratic recoveries.In this paper a new parameter is introduced. This parameter relates the maximum addition recovery observed over the time needed to achieve this maximum recovery."

Jan 1, 2002