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By Robert B. Parsons

"Ontario and Quebec taxpayers will have to dig deeper into their pockets to pay more tax, according to budget papers tabled in these provinces in May 1993. Individuals will be hardest hit, but corporations will also have to ante up in the face of higher rates, reduced deductions, and new taxes.Up, up, and away...Somewhere in the bleak picture of the 1993 Quebec and Ontario budgets, there is a bit of good news for the mining industry.Careful scrutiny reveals:• Ontario will correct a capital tax provision which inadvertently penalizes flow through share issuers;• Quebec's flow-through incentives will be extended to December 31, 1995; and • both Quebec and Ontario will allow deductions for mine site reclamation payments.The industry may also find some comfort in the fact that Ontario's new corporate minimum tax will be profit-based (unlike the federal minimum tax), so that non-producers should not face a liability for this tax. There is some concern though, about Quebec's announcement that the refundable credit mechanism in the Mining Duties Act will be reviewed."

Jan 1, 1993

By K. M. Deen, E. Asselin

Hydrometallurgical processes, i.e., Cu extraction from a mineral concentrate and Zn electrowinning, are coupled in a battery-like system. A naturally-sourced CuFeS2 concentrate mixed with activated carbon is used as a positive slurry electrode separated by a membrane from the negative compartment. The Zn is deposited on the negative Al current collector from the circulating solution containing 100 g L–1 Zn2+ in 0.2 M H2SO4. In this battery-like system, both CuFeS2 oxidation and Zn deposition are possible during the charging cycle. The additional benefit of this setup is the energy storage if discharged by re-dissolving the Zn in the negative compartment. Cyclic charge/discharge testing revealed oxidation of the mineral concentrate supported by the Zn2+/Zn redox reaction. The coulombic and energy efficiencies increased monotonically to 95.6% and 43%, respectively, with approximately 7% Cu extraction during the first 10 charge/discharge cycles (completed in 2.4 hours). The discharge energy density also increased from 2.7 to 36.2 mWh L–1. In the following 90 cycles, the low energy (~14%) and coulombic (~33%) efficiencies that were obtained confirmed the progress of irreversible reactions e.g. Cu extraction from the mineral concentrate. Overall, approximately 16% Cu was extracted from the mineral concentrate over 100 charge/discharge cycles (or about 12.2 hours). INTRODUCTION Chalcopyrite (CuFeS2) is the main economic copper-bearing mineral, which is generally processed through pyro-metallurgical methods to produce Cu. However, environmental challenges with smelting, depletion of high-grade ores and a large number of impurities (some toxic) have resulted in continued research aimed at the development of hydrometallurgical technologies to process CuFeS2. There are a number of different proposed hydrometallurgical routes in the literature to treat CuFeS2 concentrates, but only a few have attained commercial acceptance (Dreisinger, 2006). Zn is another commercially important metal that is mainly produced via acid leaching of roasted sphalerite (ZnS). The pregnant leach solution is rigorously purified to remove all the soluble metal impurities, particularly those that are electrochemically more noble than Zn and present large kinetic activity towards H2 evolution (Hu & Piron, 1992; Mackinnon, Brannen, & Fenn, 1987; Mureşan, Maurin, Oniciu, & Gaga, 1996). Metal impurities such as Cu, Co, Ni, Cd, Pb, Sb, As, Ge and Fe etc., if they exist in the leach liquor beyond the tolerance limits, can decrease the current efficiency during electrowinning and deteriorate the deposit quality (Alfantazi & Dreisinger, 2001). A complete flow sheet, describing the process steps of Zn metal production from mine site to pure metal is presented elsewhere (Brown, Meisenhelder, & Yao, 1983).

Jan 1, 2019

By Yve Potvin, Fabien Miller, Deni Jacob

"The potential benefits of measuring the volume of excavated open stope are enormous. By comparing the actual excavation of the orebody contour, it is possible to determine the “real"" amount of mining dilution, as well as the ore left in place. Noranda Technology Centre (NTC) has developed a stope survey system that allows for rapid and efficency measurement of underground excavation volumes. The system comprises a commercial laser (EDM), a set of lightweight rigid rods, an automated scanning device, a hand-held data logger and Autocad-based software for volume calculation and drawing manipulations. This system is an invaluable tool for the optimization of mining practices and could also be used for the delineation of caving areas. IntroductionDilution is the most common and devastating mine disease. In some instance s it could systematically cripple the profitability of an operation, and in more extreme cases, it could become a terminal disease. The Northern Miner Journal (1988) reported that many operations have closed because of uncontrolled dilution, before they even completed their first year of production. Other studies (Pakalnis, 1986) have shown that approximately 40% of all underground operations have more than 20% dilution. Considering that every ton of dilution costs in the neighbourhood of $25, the total direct cost of dilution to the Canadian mining industry may easily exceed one hundred million dollars per year.The dilution problem has been a major concern to Noranda Minerals for some time and in 1984 a comprehensive geomechanics research program was created at the Noranda Technology Centre (NTC) in Pointe-Claire, Quebec. New empirical stope dimensioning techniques, improved cable bolting techniques and sophisticated ground control instrumentation projects (among others) contributed to improve the situation at Noranda.A new tool which can have a very significant impact on the ""war"" against dilution is being developed by the Noranda Technology Centre. The laser stope survey system allows for a rapid, precise and efficient measurement of underground excavation volumes. By comparing the excavation planned with the volume excavated, it becomes possible to determine the ""real"" amount of mining dilution as well as the amount of ore left in place. This system may also allow for early detection of a dilution problem. As with other diseases, early detection provides the best chance for a fast and total recovery."

Jan 1, 1992

By E. Kouame, M. D. Everell, D. Hodouin, T. Kasongo

"To properly operate a mineral beneficiation plant it is often necessary to have systematic evaluations of the performances of a piece of machinery, of one of the processes or of the plant as a whole. The state of a process can be described from a collection of data: flow-rate values, particle-size distributions and chemical compositions of the various streams of the circuit studied.However, the obtained raw data are generally redundant and inconsistent from a material balance viewpoint, due to natural disturbances, sampling errors, unreliable instrument readouts and laboratory analysis inaccuracies.BILMAT is a computer program which upgrades mineral processing data, adjusting them in a least-squares sense in order that they may verify material conservation constraints. As a consequence, the program is able to calculate the best values of unmeasured flow rates (such as. circulating load ratios). BILMAT is a very general program in the sense that it can accept various data from any type of mineral processing circuit, and its usefulness is demonstrated here for three processing circuits of a pyrochlore concentration plant: grinding, desliming and flotation.IntroductionComputation of the material balance around any metallurgical process, that is the determination of stream flow rates and composition. is a basic step in its evaluation. In spite of the simplicity of the physical laws of mass conservation. and of the very fundamental need to know the flow of components around a process. it appears, particularly in mineral processing. that material balancing is quite often a difficult task. The reasons for this involve the problems associated with collecting measurements in mineral dressing plants. They are generally poorly instrumented and invariably data must be collected through hand sampling. Due to the heterogeneous nature of the streams, segregation occurs and samples are often not adequately representative, a problem made worse by the lack of circuit sampling facilities, which are often completely ignored by plant designers. Furthermore, the nature of the measurements to be performed (for instance particle size distributions in the fine range) frequently gives inaccurate results."

Jan 1, 1981

By Barry James

"This paper discusses past and current energy use patterns in the mining and manufacturing sectors of the industrial minerals industry. Information is presented on the primary energy input types as purchased by the industry, the quality and form of the energy actually required by the various production processes, and the residual form of this energy, either embodied in the product or rejected in gaseous and liquid waste heat streams. With the continuing concerns about the availability of energy combined with the rapidly increasing cost of energy as a production input, the reduction of energy usage through improved efficiency will undoubtedly be an increasing priority for the industry during the 1980s. Reduced energy consumption through investment to improve energy efficiency appears to be advantageous from both the corporate and national perspectives.IntroductionEnergy, like labour and materials, is one of the basic production input s to the various mining, processing and manufacturing production stages in the industrial minerals industry. Energy costs, as a percentage of total production costs, have been well above the average for industry in Canada, accounting for more than 50 cents out of every dollar in the most extreme cases. Consequently, energy has always been a relatively important management concern in the industrial minerals industry.The energy supply and price situation in Canada and internationally has been changing rapidly since 1973, following a long period characterized by declining real energy prices and an abundance and wide choice of energy supplies. It is generally accepted that energy prices will continue to increase rapidly, and that there will be uncertainties about the long-term continuity of supply of some energy types. In essence, a period of relative stability has been replaced by a period of relative uncertainty. In such a changing situation, a reassessment of the role of energy as a production input is appropriate.The following sections outline some of the effects of the changing energy scene on the industrial minerals industry. These effects are dealt with primarily in terms of energy costs, because, in most circumstances, a change in the cost of energy as a production input is the end result of both energy price and energy supply changes."

Jan 1, 1981

By R. G. Bradbury

The paper uses two hypothetical, but typical, situations to show that hydraulic rock drilling equipment has very significant economic advantages over pneumatic equipment both in drifting applications (even in the situation where advantage is not taken of the high productive capacity of the hydraulic drill) and production drilling applications. Other factors, including the non-economic advantages and the disadvantages of hydraulic drilling, are discussed. The paper concludes with a brief analysis of why the Canadian mining industry has been slow to take advantage of this apparent broadly advantageous advance in rock drilling technology.

Jan 1, 1979

By J. Aiello

"A brief history of previous mining activity on Coal Mountain, near Corbin, British Columbia, is followed by a description of the steps leading up to the resumption of mining in /974 by Byron Creek Collieries. New developments, including a preparation plant, a rail spur and a totally enclosed facility, as well as operating techniques, are also discussed. IntroductionThe Corbin Mine of Byron Creek Collieries Limited is located in southeastern British Columbia, approximately 110 air miles southwest of Calgary (Fig. I), 15 miles south of Highway 3 via a newly constructed provincial road (Fig. 2). Development of the area began on July 30, 1905, when D.C. Corbin, a prominent businessman from the northwestern U.S., and his associate E.J . Robert s, first visited the site of Coal Mountain on horseback. Coal was in great demand by railways and other industrial users, so the Corbin Coal and Coke Co. , after acquiring 15,000 acres of land in the area , began to develop a mine.F.J. Roberts was responsible for the construction of the 14-mile rail spur, the Eastern British Columbia Railway, which joined the mine to the CPR main line at the McGillivray Loop. Rail access to the mine and its developing community, Corbin, B.C., was completed in September 1908, the same year that the first underground mine began production.The Corbin Coal and Coke Co. operated six mines on Coal Mountain (Fig. 3), and production from 1908 to 1930 inclusive totalled 2,337,800 tons. This production was allocated to the mines as shown in Table 1. No.3, 4 and 6 mines were operated intermittently from 1931 to 1935."

Jan 1, 1980

By D. S. Conochie

The world is poised for rapid growth in consumption as large, less developed economies acquire greater wealth. It might be expected that there would be a corresponding growth in waste generation, but this might not necessarily be the case. The metallurgical industry has an excellent record of process development which has allowed it to provide a high tonnage supply of low cost, high quality metals. Environmental challenges have been faced and indeed the recycling of scrap iron through the electric arc furnace has made a massive contribution to cleaning up obsolete structures and equipment of past generations. Issues in waste generation and processing still remain, and the expectation for cleaner processing and environmental performance continues to rise. The waste impact of key process developments of the last century and the recent developments in metallurgical waste processing in Canada will be outlined. The potential to use state of the art design tools to produce the next generation of zero waste processes will then be explored.

Jan 1, 2004

By Umbreen Agha, Stephan L. Chryssoulis, A. Margaritis

"The deportment of gold in samples of the biooxidation feed and product from the Harbour Lights mine in Western Australia was determined using optical microscopy and microbeam techniques such as Secondary Ion Mass Spectrometry (SIMS), Time-of-Flight Laser Ionization Mass Spectrometry (TOF-LIMS), and Electron Probe Microanalysis (EPMA). The main objective was to determine the mechanisms by which acidophilic bacteria (Thiobacillus ferrooxidans) liberate refractory gold which is locked in a sulphide minerals host as visible gold inclusions (> 0.1 µm) and as submicroscopic or 'invisible' gold.Using the integrated mineralogical approach approximately 99% and 100% of the assayed gold in the biooxidation feed and biooxidation product was accounted for. The results were compared to and verified by chemical assays.The gold deportment study indicates that during biooxidation, locked visible and 'invisible' gold is rendered cyanidable by the direct action of Thiobacillus ferrooxidans as well as indirect chemical leaching. Visible gold which is enclosed in sulphide minerals is liberated or partially exposed and is therefore rendered cyanidable as the host mineral is oxidized and dissolved. 'Invisible' gold either coalesces on the surface of the host sulphide mineral as the particle is dissolved or is released into the liquid phase and immediately adsorbs onto the surface of other ore particles with a net negative charge.The shakeflask suspension indicates that direct bacterial oxidation pits and channels correspond to zones of 'invisible' gold and arsenic (in pyrite) enrichment in the host sulphide mineral."

Jan 1, 1996

By Michael L. Free, Zongliang Zhang, Joshua M. Werner

In the copper electrowinning process, short-circuiting between the anodes and the cathodes is a critical problem that changes the current allocation among local electrodes and reduces the current efficiency significantly. Possible reasons for the short-circuiting include the improper alignment of the electrode, bent electrode, and nodules on the cathode surface. In typical tankhouses, there is often a time between shorting and harvesting as well as between shorting and clearing. Therefore, it is inevitable to have short-circuiting affect the operation performance in practical electrowinning operations. However, one key piece of missing data is the actual measurements of the current efficiency as short-circuiting is approached and allowed to continue. Consequently, short-circuiting tests that allow tracking of electrowinning parameters before and after short-circuiting were performed in a laboratory scale Cu electrowinning cell. In the tests, the electrode spacing change, the mass of electrodeposited Cu, the deposition morphology, and the current allocation as well as the current efficiency before and after short-circuiting were studied. Results show that the short- circuiting affects the current allocation and the current efficiency significantly. Moreover, it changes the Cu deposition on the short-circuited cathode and therefore causes problems for Cu electrowinning. INTRODUCTION Electrowinning (EW) is commonly used for copper production around the world, with a rated production from 120,000 to 200,000 tons per year per operation (Wiechmann, Aqueveque, Henríquez, Muñoz, & Morales, 2014). In Cu electrowinning, Cu ions in the electrolyte are reduced on the cathode surface as metallic copper with a DC current, while on the anode, a counter anodic reaction occurs with oxygen gas generation (Werner, Zeng, Free, Zhang, & Cho, 2018; Zhang, Werner, & Free, 2018; Zhang, Werner, & Free, 2018). In copper electrowinning, an average current density of 200 to 400 A/m2 is applied to the electrowinning cell (Wiechmann et al., 2014). As the Cu deposits on the cathode, the distance between anode and cathode reduces and most of the time, short-circuiting forms between some anodes and cathodes in a large tankhouse containing thousands of electrodes, reducing the current efficiency and increasing the energy consumption significantly. The current efficiency in well-run copper EW operations is typically above 90 %. Most of the unused current is wasted through short circuits, stray currents, and by-byproduct formation (Davenport, King, Schlesinger, & Biswas, 2002; Wiechmann, Vidal, Pagliero, & Gonzalez, 2002; Wiechmann, Morales, & Aqueveque, 2010). Usually, in the tankhouse, the short-circuiting increases the current in the involved cathode by up to 1500 A (Wiechmann et al., 2010). Multiple reasons can cause the short-circuiting in the cell, and the most common reasons include the uneven current distribution among cathodes, tilted electrodes, bent electrodes, and nodules formed due to the large deposition roughness. Recognition of this challenge in the Cu electrowinning process has led researchers to perform many investigations on approaches to avoid and reduce the short-circuiting in the cell. A series of research investigations have been conducted to develop and improve a new type of intercell bar for Cu electrowinning (Wiechmann et al., 2002; Wiechmann, Morales, Aqueveque, & Burgos, 2007; Wiechmann, Morales, & Aqueveque, 2009; Wiechmann et al., 2010; Wiechmann et al., 2014). The associated test results show that this new design limits the occurrence and magnitude of short circuits and allows operation at higher current densities. Sandoval, Clayton, Dominguez, Unger, and Robinson (2010) stated several keys to control short circuits, such as maintaining the straightness of the cathode, removing “edge hair” from the cathode starter, and maintaining electrode alignment in the cell. Prengaman and Siegmund (1999) from RSR technologies developed a new Pb-Ca-Sn anode to prevent the anode deformation, thereby reducing the short-circuiting in the Cu electrowinning cell. Although the negative effects of short-circuiting on the Cu electrowinning have been recognized, and various investigations have been conducted to address this issue, the actual measurements of the electrowinning behavior and performance as short-circuiting is approached and allowed to continue are seldom reported. However, in typical tankhouses, there is a time between when shorting occurs and harvesting/clearing are performed. One key factor in determining the harvest time is the frequency of shorting. Consequently, we have performed short-circuiting tests that allow us to track electrowinning parameters before and after short-circuiting.

Jan 1, 2019

By B. M. Das, V. J. Hucka, J. H. Tu

Subsidence can cause serious damage to surface installations such as railroads, highways, pipelines, buildings and other facilities over a period of many years. Although total elimination of the effects of subsidence is difficult, the damage can be minimized through a systematic analysis. An example of such a study for reducing the effects of subsidence on pipelines is presented in this paper. Subsidence-induced stresses on a pipeline over some coal mining properties in Utah have been analyzed using a computer with graphics capabilities. The results are useful in predicting the extent of damages due to mining subsidence. In view of the gradual replacement of room-and-pillar mining by longwall with caving, this sort of analysis will become more and more important. In the next phase of this study the predicted results will be compared with the permissible stress levels on pipelines over actual subsided areas in an actual case.

Jan 1, 1989

By J. B. Hinzer, J. D. Harvey

"Noranda's Lyon Lake property in the Sturgeon Lake area of Northwestern Ontario was staked by Mattagami Lake Mines Limited in May 1969 to cover airborne Input anomalies. Subsequent ground geophysical and diamond drilling programs resulted in the disco very of the Boundary Extension, Lake and Creek ore zones. As of December 31, 1978, ore reserves were estimated at 3,945,000 tons assaying 6.53 per cent Zn, 1.24 per cent Cu, 0.63 per cent Pb, 3.42 oz/ton Ag and 0.010 oz/ton Au.These deposits are hosted within the South Sturgeon Lake volcanic pile of Archean age, which consists of several cycles of basic intermediate and felsic volcanic materials overlain by a sedimentary iron formation and built upon a plutonic base (Franklin , ' 1975). The top 50 m of the second felsic cycle, according to mine terminolo gy, contains the mineralization within Quartzphenocryst- bearing felsic lapilli tuff and underlying thin discontinuous graphitic sediments and altered coarse pyroclastics. The basal andesitic member of the overlying cycle forms the hanging wall to the ore deposits.Although there is no alteration pipe below the deposits, the coarse footwall rocks are permeated by chlorite, garnet, carbonate, iron sulphide and magnetitie-bearing veins intensifying from west to east.Immediate host rocks are alkali depleted and MnO, FeO, Zn and Cu enriched compared to Goodwin's (1972) average Archean rhyolites. Bedded pyrite-pyrrhotite-chalcopyrite lenses with sphalerite-rich tops are underlain by weakly developed stringer mineralization.Traversing eastward from the Lake Zone to the Creek Zone and toward the Sturgeon Lake Mine deposit, more rapid facies changes, more pronounced chloritic and carbonate alteration, the presence ofgarnets, greater MnO, FeO, CaO and Ag abundances, and increasing Zn/Cu and MnO/FeO ratios are apparent."

Jan 1, 1981

By Derek E. McBride

"Exploration work in the Beardmore - Tashota area has led to a reinterpretation of relationships between gold mineralization and the geologicalevolution ofthe area. The host volcanic rocks form two parallel volcanic belts connected by a much smaller cross-cutting band, which trends northeast from Beardmore to Tashota. This connecting band consists of mafic and felsic volcanic, plus clastic sedimentary rocks in a sequence conformable with the contact of the Onaman Lake Batholith to the east. A metamorphic aureole or incorporated xenoliths are lacking along this major contact and the only intrusive relationship observed is chilling between mafic dikes and a cold host granite in proximity to it. Granite dikes are totally lacking in the volcanic succession, or the overlying sedimentary sequence. A major part of this sequence consists of a polymict basal conglomerate with granite boulders and volcanic clasts in a fine-grained chloritic matrix. The nearest source for these boulders is the Onaman Lake batholith.Gold mineralization in significant economic quantities (+ 50 000 ounces) occurs at the top or above the mafic volcanic succession as quartz bands. In the Northern Empire Mine, the band is conformable, folded, boudinaged and the mineral zoning shows a relationship to variations in the host rock, not structural overprinting. In general, where the host mafic tuff is medium-grained, the quartz band is thicker, up to a metre wide, and carries economic grade; where the tuff is finer-grained and bedded, the band is very thin and low grade.Stratigraphic control and metal zoning shows that the mineralization formed as part of the development of the volcano- sedimentary succession. The other major deposits in the area (Leitch and Sturgeon River) have a similar structural history suggesting that they are also syngenetic in terms of the stratigraphic development. Regionally, these deposits were emplaced prior to any significant tectonic deformation but at the end of the mafic volcanic event.The mafic activity was related 10 a period ofextension which caused the volcanic troughs to develop along centres of rifting. The hiatus at the end of this event permitted extensive hydrothermal systems to form and deposit siliceous exhalite bands within sedimentary or terminal mafic volcanic environments in promixity to major thermal sources. Subsequently, the Kenoran Orogeny deformed the entire succession into upright folds with a sub-vertical schistosity. Evidence shows that the deposits have remained intact since deposition."

Jan 1, 1987

By F. Prescott, D. Hiam-Galvez, J. Hiam

Mines are frequently located in remote areas with little conventional employment and few opportunities for the existing population. The development and operation of the mines results in several years of intense activity followed by a near-complete reduction in employment and opportunities after the mines are closed. Designing Sustainable Prosperity (DSP) is a method for rectifying this situation by designing for long-term growth in areas that host mines. This process involves the participation of local and national governments, local community, mining companies, investors, academics and those with sector expertise. The mines will be the catalyst for regional sustainable development. If successful, long-term economic and environmental prosperity should be the result for the areas affected by mining and, in some instances, promoting the regions as centres of excellence for a particular industry. This paper will describe how the concept works using the copper producing region of Peru and Chile as an example. Designing sustainable prosperity starts by looking at regions based on the natural resources and skills available, the infrastructure and possible energy sources. Integrated natural resource models and innovative market studies, followed by education and skills requirements, are then established to determine the potential for the region and what needs to be done to realise the possibilities. INTRODUCTION Industry 4.0, or i4.0, dubs the fourth and current industrial revolution. Where previously they have been founded on ever-increasing consumption and production, i4.0 distinguishes itself by its partial focus on reducing resource intensity; lightweighting, energy efficiency, sensors and automation to improve resource efficiency. Industry 4.0 is an era of artificial intelligence, genome editing, biometrics, renewable energy, 3D printing, autonomous vehicles and the Internet of Things (Lu, 2017). These drivers represent key opportunities for the economic future of nations and regions.

Jan 1, 2019

By A. Consigny

New "clean technologies" to treat mining and metallurgical effluents containing dissolved metals have been successfully applied at mine sites in North America and Asia, treating water flows up to 24,000 m3/day. These clean technologies offer significant benefits compared to conventional alternatives and provide a sustainable solution that eliminates residual waste sludge, improves water conservation, generates revenues from wastewater, and delivers overall improvements to the environment. This paper will profile these technologies, and provide best practice case study examples of their application at mining operations, including data for water chemistry, flows, water quality, capital and operating costs, and life cycle costs of treatment.

Jan 1, 2011

By Robert B. Parsons

"Canadian income tax legislation contains a number of provisions which serve to facilitate the structuring of business arrangements, including mineral resource ventures. These rules are often fairly complex and not easily understood. This article attempts to explain in plain and understandable language the mechanics and benefits of one of the more frequently encountered provisions, the ""Section 85 election"".IntroductionThe Canadian resource industries are probably singled out for more special attention under this country's tax legislation than any other industry. This special treatment is, of course, not always welcomed by the industry, such as where unnecessarily restrictive taxation is perceived to exist or where agonizingly complex tax legislation must be dealt with. On the other hand, certain provisions in the tax legislation treat the industry in a relatively favourable manner, including a number of rules which, in recognition of the high risk and capital requirements of the resource sector, serve to facilitate the structuring of resource ventures."

Jan 1, 1984

Operating and Social Considerations from a Contractor?s Perspective

May 1, 2013

By Brian E. Robertson

"This paper summarizes work carried out at the Dome Mine to mechanize the mining of narrow veins of less than 1.5 m in width by the introduction of new mining methods and specifically designed electric LHDs.Extensive mining trials have been conducted using sublevel blasthole, modified Avoca, and resuing mining methods. The introduction of the Microscoop and the Jarvis Clark remote, radio-controlled scooptram has increased mucking productivity.As a result of this work, additional narrow vein stopes are now being prepared for production. In the future, narrow vein stoping wil lprovide a greater percentage of the total mill tonnage.IntroductionThe Dome Mine, which is owned and operated by Dome Mines Limited, is located at Timmins, Ontario. Production has been continuous since 1910 and in 1984 was increased from 1814 to 2721 tonnes per day.At least six distinct ore types have been recognized at the mine. In general, these orebodies can be broadly categorized into wide and narrow deposits. The wide deposits are approximately lenticular in shape and vary in width from 10 m to 40 m. The narrow orebodies consist of quartz and quartzankerite veins ranging in width from a few centimetres to six metres. The average dip of the veins is 65 degrees.Since the I970s, mining activity has been largely concentrated in the wider orebodies using highly productive open sublevel blasthole and mechanized cut-and-fill stoping methods. With the demise of shrinkage stoping in 1975, investigations were initiated to develop new mining methods and introduce LHDs - truly designed for narrow orebodies. These investigations resulted in test trials of the sublevel blasthole, modified Avoca, and resuing mining methods. Consultations with equipment manufacturers and suppliers led to the development of the Jarvis Clark remote, radio-controlled electric scooptram and the introduction of the France Loader Microscoop."

Jan 1, 1986

By John H. Walsh

"ForewordThis paper is to be published in two parts in succeeding issues of the CIM Bulletin. In Part I, the problem of global climate change is explored together with a summary of the government's present policy in this field. Implications for the steel industry are examined as are possible strategic responses. Part II of the paper will present a new possibility - the joint production of iron and liquid fuels useful for transportation purposes. In the joint production case, the objective is to use carbon for more than one purpose in what might be termed a 'carbon cascading' technique. ABSTRACTIt is becoming increasingly probable that emissions of carbon dioxide from the fossil fuels will have to be reduced to deal with the threat of global warming. This issue is likely to be resolved one way or the other in the period 1995 to 2000 which does not leave much time to develop responsive options. In the intervening period, the policy of the Government of Canada is to stabilize emissions of greenhouse gases at their 1990 level by 2000, by encouraging greater efficiency in the use of energy. Should further reductions prove necessary, economic instruments would probably be employed but these would not be applied before a comprehensive international agreement is reached.There are three main themes in this paper: it is assumed that measures to control carbon dioxide emissions will in fact be necessary by the tum of the century; that there will be a rising need for liquid fuels to supply the world's steadily growing fleet of motor vehicles for many years to come, and that the future niche for Canada 's industry in such a carbon-constrained world will be the operation of the energy-intensive industries with efficiency and environmental sensitivity.The steel industry, as a large user of both coal and energy in other forms, would be significantly affected by a need to reduce carbon dioxide emissions. This paper first examines what might be called the conventional responses open to the industry in such a situation and then explores a new possibility for making better use of carbon by the co-production of iron and liquid fuels."

Jan 1, 1992

By Marc C. Betournay, John E. Udd

"In this study, the authors investigated the stabilities of slopes cut predominantly into Trenton limestone in a large quarry in the Montreal region. Analyses of the bench and pit walls indicated that small-scale toppling, ravelling, and wedge failures are the most likely modes of instabilities. Because most of the joints dip steeply, however, the conclusion was made that relatively high walls could probably be justified.The field investigations were supplemented with the determinations of the shearing strengths of artificial discontinuities that were cut into samples of the limestone. The properties of a fine-grained limestone were found to be influenced very much by the magnitudes of the loads that were applied, while the properties of a crystalline limestone were found to be much less, or not load-dependent.The study is one of a number that are being conducted in this area.IntroductionExtensive quarrying has been done in the sedimentary strata of the Montreal area for a very long time. By any standards, it can be said that the Island of Montreal is a major mining area. At present, approximately 20 quarries are being operated in, or near, the city of Montreal.In addition to the millions of tons of limestone that are removed each year, a large number of excavations for foundations are cut into the sedimentary rocks.To date, however, very little information has been published concerning the engineering properties of the local geological materials. No mention is made of this aspect in the references which are presently available.Because of this lack of information, the senior author has initiated a study in which the strength properties of most of the rock types, and of the natural discontinuities contained in these, would be investigated. To date, the results of one other investigation have been published and other work is in process. It is hoped that the end result will be a comprehensive knowledge of the important strength properties of all of the rocks in the entire region."

Jan 1, 1983