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By G. S. Hume

"THERE HAS BEEN a marked growth in the petroleum industry in Canada since the end of the war. The rate of growth in the demand for oil products has exceeded that in United States, although the per capita consumption is still less. Estimates of the consumption of petroleum and petroleum products in Canada in 1951 are approximately 154,000,000 barrels, which is slightly more than 11 •barrels per capita, whereas the estimated consumption in United States for the same period, according to World Petroleum, is placed at 2,619,- 970,000 barrels. This, on the basis of a population of 154,000,000, would be equivalent to 17 barrels per capita. The increase in consumption of the petroleum and products is world wide. World production in 1951 has been estimated (Oil and Gas Journal) at 11,700,000 barrels a day or more than 41;4, billion barrels for the year. United States production increased 13.7 per cent to 6,143,000 •barrels a day and Canada'.s ,, total production increased about 65 per cent from a total of 29,091,235 •barrels in 1950 to an estimated (Dominion Bureau of Statistics) 48,096,800 barrels in 1951.The trend to use increased amounts of petroleum and petroleum products, particularly in the United States and Canada, has also been supplemented by increased use of natural gas. The rate of expansion of the consumption of natural gas in United States in the past few years has been very rapid, increasing from 2,600 billion cubic feet in 1940 to 5,975 billion in 1950, with the proven reserves in the same period increasing from 85,000 billion to 186,000 billion cubic feet."

Jan 1, 1952

By A. E. Moss

"IntroductionTHE WORLD-WIDE search for iron ore has been vastly accelerated during the past fifteen years .and Canada is playing a most prominent role in this prospecting boom. During this period, the search for .and development of iron ore deposits in Canada bas proven eminently successful and there is every indication that exploration will continue to be active for many years.This paper has been prepared primarily for the information of those who have bad little or no experience in iron ore exploration. For convenience, it is divided into three parts: ( 1) a brief discussion of the marketing of iron ores, with special reference to Canadian production; (2) a summary of the main features to be considered when prospecting for or evaluating a potential iron ore deposit; and (3) an outline of the methods and procedures used in the search for the direct-shipping iron ores in the Quebec•-Labrador iron ore field.The Iron Ore MarketDue to the tremendous tonnages of high-grade direct-shipping iron ore indicated in the iron ore fields of the Quebec-Labrador and Steep •Rock areas, it might be assumed that there would have been a sharp decline in iron ore prospecting in this country. On the contrary, the development of these two major fields, which must be classed among the world's greatest, has been responsible for much of the current activity. The search for high and medium grade magnetite deposits is being• conducted in many parts of the country and a number of these have reached the development stage. Production is being expanded from the known fields, such as Wabana in Newfoundland and Michipicoten in Ontario."

Jan 1, 1955

By J. Hall Carpenter

"Wet concentration has, in the history of ore dressing, been the primary treatment method following crushing, grinding and sizing, when these have been necessary. The evolution of new methods of gravity concentration has been comparatively slow.Today, the most significant and sophisticated of the new types of gravity concentrators is, no doubt, the cone concentrator developed by Ernst Reichert of Mineral Deposits Pty. Limited in Southport, Australia. These units have now had some years of use in the field, are becoming one of the standard tools of the industry and their metallurgical results, as outlined in this paper, are out-standing."

Jan 1, 1966

By Scott Hommema

? Bitumen in the oil sand averages Bitumen 12 wt%; water makes up 4 wt% ? Imperial Oil (operator) and ExxonMobil developing Kearl Leases #6, 36, 87 (~200 sq. km) ? Target resource > 4 Billion Barrels ? 3 Phase development, ~100 kbd per phase High-quality resource ? Surface mineable bitumen ? Average properties (full lease) ? TV:BIP < 8 ? Grade > 12 wt% bitumen ? Ore thickness of 40 m ? Overburden thickness of 20 m Status ? Phase 1 ? Front end engineering and design underway ? Detailed engineering to start 2008

May 1, 2008

By Y. Béliveau

Emission of perfluorocarbon gases, CF4 and C2F6, produced during anode effects from aluminum electrolytic cells are a significant part of the total equivalent CO2 emitted by aluminum plants. With the current concerns about global warming, the reduction of these PFC gases is a key issue in reducing greenhouse gases for a smelter and achieving GHG emission agreement goals. This paper will present the approach taken by the Alcoa vertical-stud Soderberg plant in Baie-Comeau to reduce GHG emissions generated during anode effects and close emission gaps with other Alcoa Soderberg plants. The approach has been to adapt the existing technology in place at the Baie-Comeau Soderberg plant. PFC emissions were lowered by reducing both the anode effect duration and frequency through different methods. Examples of change include: implementing skimming practices and wider side crust break area for better alumina dissolution in bath, increasing the ratio between reacted and pure alumina, reducing the time to declare anode effects in the potrooms, implementing best work practices and finally educating the workforce on the importance of reducing PFC emissions.

Jan 1, 2007

By Edward R. Lauer

Energy conservation is an integral part of Canada&apos;s energy strategy. We must pursue conservation and energy management vigorously if we are to remain competitive in domestic and world markets, and minimize our reliance on external energy sources. Energy management in industry is discussed from three viewpoints: (l) as a means of directly improving profitability; (2) as a major factor in the supply picture; and (3) as a significant influence on Canada&apos;s balance of payments and over-all economic well-being. The Federal role in promoting a voluntary industrial energy conservation program is described.

Jan 1, 1977

By E. J. Burrough

Coal Reserves The Crowsnest Pass coal fields form part of a greater area which comprises the Inner Foothills belt of the Alberta coal fields and the southeastern coal fields of British Columbia. The most valuable and most extensive reserves of the bituminous coals of Canada are concentrated in this?area, of which the Crowsnest Pass fields form an important part. The extent of these coal reserves together with those of the rest of Canada were recently studied by the Geological Survey of Canada for the Royal Commission on Coal of 1946 (1). Quotin from the report, it is of interest to note that, prior to this work, the most widely known, and in fact the only Canadian-wide estimates of, coal reserves of Canada available to the Commission were those prepared by Dr. Dowling in 1913 (2). At that time it was estimated that Canada&apos;s reserves of coal were over twelve hundred billion tons. The more recent estimates of mineable coal for the whole of Canada are of the order of 10 per cent of that figure and are reported. as 99 billion tons, which is further reduced to 40 billion tons on the basis of the estimation of recoverable coal. This considerable divergence in estimated reserves is explained in part by the big difference in the bases of measurements. For example, in the original report, seams of one foot occurring at a depth of 4,000 feet were included in the estimates.

Jan 1, 1951

By C. S. Touchard, F. Bourgeois, L. Cassayre, Julcour-Lebigue C.

Developing a hydrometallurgical process that can overcome the refractory nature of chalcopyrite (CuFeS2) to leaching still eludes the minerals industry, despite major research efforts spanning decades. The several leaching experiments of this ore in sulfuric acid tend toward the same conclusion that the precipitation of elemental sulfur or iron containing species are the main dissolution inhibitors. Describing both the electrolyte composition and the various solid phases in equilibrium for the Fe-H2SO4-H2O system is essential to overcome this issue and to find an operating window. According to the thermodynamic models and to the thermodynamic data, we demonstrate, in this study, the need to use the Specific ion Interactive Theory (SIT) model to describe complex electrolytic systems through a limited number of parameters. Hence, the binary interactions for our case study have to be defined and estimated. This work develops a methodology to determine these parameters of the SIT model up to 90°C and an acid concentration of 1 mol/kg from published data for H2SO4-H2O and Fe(II)-H2SO4-H2O sub-systems or from new experimental data for the Fe(III)-H2SO4-H2O one. This method will eventually be applied to copper systems to lead to a thermodynamic description of the complete CuFeS2-H2SO4-H2O system. INTRODUCTION A leaching process consists in the dissolution of a solid phase into an aqueous medium in order to extract compounds of interest. It is a key step in the hydrometallurgical processes used in the primary production and recycling of metal components. One of the main leaching issues is the formation of passivating layers on the surface of solid particles, whose consequence is a partial or total hindrance of the dissolution. The leaching of chalcopyrite (CuFeS2) in sulfuric acid is a prime example. No industrial solution for the atmospheric pressure leaching of this ore has been developed to date because of passivation phenomena caused by the formation of elemental sulfur or iron-containing precipitates on the surface of the particles (Li, Kawashima, Li, Chandra, & Gerson, 2013). In the 1970s, the Pourbaix diagrams established for the Cu-Fe-S-H2O system at 25°C for low concentrated solutions (Garrels & Christ, 1965; Peters, 1976) agreed that copper and iron are fully dissolved at high potential and in acidic medium (pH < 4). However, they neglected the many stable solid phases that can form in these conditions. In addition, the Pourbaix diagrams of chalcopyrite in water, calculated with two recent databases (FactPS and Thermoddem 2017) associated to FactSage and PhreeqC softwares respectively, show large discrepancies at 75°C (Figure 1). Indeed, at high potential, FactSage predicts the formation of goethite FeOOH at a pH value of 1, while PhreeqC predicts the formation of jarosite (H3O)[Fe3(SO4)2(OH)6] for pH greater than 2.5.

Jan 1, 2019

By Derrick Hunter, Pat Feighan, Keith Chrystall, David Wells

"Equipment which may be remotely operated, has some degree of on-board intelligence, and which for periods of time may operate autonomously, is referred to as telerobotic. Recent advances in electronics, computers and hydraulic equipment have dramatically reduced the cost and simplified the process of converting standard industrial equipment to telerobotic control. The benefits of telerobotic equipment include improved safety by removing the operator from dangerous situations, reduced maintenance costs and increased productivity. This technology has been proven in various military, nuclear, and police applications.The surface mining industry has expressed an interest in automation and is characterized by a willingness to use remotely operated equipment, however, the majority of telerobotic equipment currently in use is experimental or prototypical. Potential applications of telerobotic equipment for surface mining include remote operation of equipment near dangerous high walls and other unsafe areas, utilization of robotic trucks for routine hauling operations, and control of jointed equipment. In addition, component technologies of telerobotic systems are relevant to various forms of condition monitoring, operator feedback systems, and vehicle positioning.Attention must now be directed toward resolving more complex problems associated with enhancing feedback to the operator, improving the man/machine interface, and ultimately, improving efficiency. Removal of the human operator from the work site introduces significant complications in replacing the sensory inputs that an operator normally uses to efficiently run his machinery. These can be difficult to define and even more difficult to replicate remotely and may include restrictions pertaining to vision, hearing, and touch.In cooperation with Defence Research Establishment Suffield and the Alberta Research Council, Robotech Industries Ltd. is pursuing the development of additional technologies to further enhance an operator’s ability to control remote telerobotic equipment. These developments include a head-mounted display, additional control station displays and improvements to coordinated motion control software. Prototypes of these developments are expected to be completed and tested by the fourth quarter of 1997."

Jan 1, 1996

By Michael J. Rosko

Methods have been developed for processing and analyzing reflected solar radiation data obtained by Landsat 5 Thematic Mapper multispectral scanner. Spatial resolution for the Landsat series satellites is 30 meters per side per pixel. Materials on the Earth?s surface absorb or reflect different parts of the electromagnetic spectrum depending on their physical and chemical properties and, therefore, typically have characteristic spectral ?signatures?. Using these signatures, environmental parameters such as surface water and vegetation may be identified and analyzed. Principal advantages of the satellite image method for environmental monitoring include: a relatively long historic period beginning in 1985 for which information is available, the reliable numerical basis for the results, and the ability to assemble a historic environmental baseline and provide on-going monitoring for large or remote areas where standard monitoring methods may not be practical. However, because the long-term continued operation of Landsat 5 is problematic due to the age of the equipment, QuickBird and IKONOS satellite images were processed to determine if the two systems are sufficiently similar in their results to allow continuing monitoring using QuickBird data. The QuickBird satellite was launched in 2001 and collects the same visible and near infrared spectral bandwidths as Landsat 5, allowing for equivalent process algorithms for QuickBird, IKONOS, and Landsat 5 data. Spatial resolution for the QuickBird images is 2.4 meter per side, allowing for more detailed characterization of the land surface; spatial resolution for the IKONOS images is 4 meter per side. Because of several differences between the satellite systems, including degradation of the Landsat 5 sensor, it is necessary to calibrate QuickBird and IKONOS results to the Landsat results to verify similarity. Recent images from the satellite systems have been processed and results have been compared to determine the validity of comparing Landsat 5 and QuickBird/IKONOS images so that these newer data can be used reliably in the future instead of Landsat 5 data. Results from this comparison are presented in this paper and suggest that analyses for vegetation using the two satellite systems are comparable, and that little calibration is required. Results from comparison of surface water results from the two systems are less comparable and is currently being investigated by the authors.

Oct 1, 2009

By J. C. Allan

THE purpose of this paper is to outline the pogress made in the development o the gravity separation method o ore dressing known as Sink-and-Float, which, in the opinion of the writers, has now reached a stage justifying the claim that this new method marks a highly important advance in the technique . The essential feature of the newest development of this process is the extremely accurate separation achieved. This is responsible for higher extraction in the sink-and-float unit on coarse sizes and, in consequence, for substantially higher overall recoveries. Whilst this is the most remarkable feature of the new process, it has further important contributions to make to ore dressing under the following heads: (1) The introduction of the sink-and-float separator as a buffer helps to iron-out irregularities in the mill feed. By supplying a concentrate of constant grade to the flotation section, the process also indirectly improves overall recovery. (2) The addition of a sink-and-float unit to an existing mill results in substantial increase in capacity at low per ton capital cost. (3) Where the plant can be installed underground for the pre-treatment of low-grade ores, there is a saving in hoisting costs, and excellent &apos;fill&apos; is provided near the point of use. ( 4) Low-grade mixed oxide-sulphide copper ores may be pre-concentrated, thereby producing a flotation feed sufficiently rich to render the oxide residue from such flotation economic for subsequent treatment by leaching or other methods. (5) Application of the process eliminates hard gangue constituents which cause high grinding costs, or gangue constituents which adversely affect flotation. The plant is compact and easily controlled. No highly skilled operators or expensive reagents are required, and the labour and power per ton are low. The separator is extremely flexible, working equally efficiently on any throughput up to its maximum capacity.

Jan 1, 1940

By H. R. Banks

SHORTLY after the commencement of operations at the Sullivan concentrator, the use of a pilot table was instituted in order to present a visual control of various products by showing the amount of galena still present in the tailing from several stages of flotation. Among the products so treated, the final tailing was later included. It was sratifying to note that very little free galena was escaping, but a fine streak o a whitish mineral appeared at the concentrate zone. This mineral was identified as cassiterite. The amount was small and the newly recognized component in an already complex ore was considered primarily as of academic interest. However, the problem of recovering a usable metal was intriguing and, as opportunity presented itself in temporary lulls in research on Sullivan and other ores, the concentration of tin was a useful &apos;bit of knitting&apos; to go on with. It was recognized from the start that the bulk of the mill tailing would have to be floated and the residue subjected to gravity treatment. Since one of the predominating features of Sullivan concentration operation has been the necessity of fine grinding, the problem of gravity concentration was thereby intensified. Several batch runs were made, and sufficient pulp was treated to produce about one ton of final tin concentrate assaying 67 percent tin. The overall recovery was under 30 percent and the estimated profit at full tonnage was only marginal. Testing was resumed several years later, when the price of tin again appeared attractive, in an attempt to develop a more compact plant with better recovery of tin. The weakness of the original plan of concentration was the large number of tables required to treat a feed so low in tin.

Jan 1, 1941

By J. Clark

Erosion control during the mining cycle can be more effectively planned using Erosion and Sedimentation Control Plans (ESCPs). This raises the issue of who should develop an Erosion and Sedimentation Control Plan Guidance document (ESCPG) to standardize the content of ESCPs. A search for ESCPG documents in Canada revealed no examples for mine sites. In the U.S. there are a number of regulatory authorities who developed such documents for mine sites, including EPA. An ESCPG is expected to result in: (a) plans will be more standardized (b) more clarity and efficiency for those generating ESCPs; (c) assisting regulators tasked with reviewing/approving ESCPs; (d) providing guidance for the mine effluent permitting process relative to sediment control; (e) providing a basis for developing and including ESCPs in the Environmental Assessment (EA) phase and the mine economic assessment; (f) applying and optimizing ESCPs above the ?watersheds? of sediment ponds; (g) utilizing the ESCPG document for ?exploration? sites; (h) lowering the risk of adversely impacting water quality downstream of mining activities; (i) providing a methodology for determining the need for sedimentation pond(s) during the construction and production phases; and (j) providing a clear environmental sustainability message relative to sediment control if the mining industry takes the lead in developing an ESCPG. ESCPs will proactively create increased administrative (regulatory) efficiency in the EA and sub-EA reviews relative to erosion control and sediment release from mine sites. This also assists the new initiative in BC, One Project, One Process (OPOP) and synchronous permitting (a variation of concurrent permitting): as an example, enhanced erosion control planning at the EA phase then allows the synchronous permitting initiative to proceed efficiently, particularly for the mine permit (Ministry of Energy, Mines and Natural Gas) and effluent permit (Ministry of Environment). Approximately twenty more management plans (e.g. ARD/ML, explosive management, emergency response, hazardous waste, sediment pond operation, environmental effects, environmental sampling, etc.) may also be entered into the EA process to create increased efficiency, and then feed into the synchronous permitting effort. The BC OPOP initiative also adds support to the Canadian Federal ?One Project, One Review Process? approach. The ESCP and a sediment pond management plan will also address the Canadian Metal Mining Effluent Regulations requirement for all discharges from mine sites to meet a grab sample of 30 mg/L Total Suspended Solids.

Aug 1, 2013

By J. J. Fitzpatrick

"This paper deals with the methods used by Quebec Cartier Mining Company in the evaluation and selection of new haulage equipment and in increasing the productivity of the existing fleet.Selection of new equipment is based upon the comparison, for each model under consideration, of the capital investment required and the estimated operating costs and production rate. The calculation of the production rate is based on a widely used estimating procedure. Actual operating conditions considered in the method include: payload, haul distance, road grade, rolling resistance, loading and dumping times, and operational efficiency. A digital computer is used to handle the large volume of repetitive calculations required. Where a fleet of haulage equipment includes trucks of different size and performance characteristics, the problem exists of assigning each truck type to the different working locations to minimize total cost. Linear programming can be used in the solution of this problem."

Jan 1, 1967

By Georges Houlachi, Raynald Labrecque, Jean-Noël Cloutier

"Electrodialysis (ED) is an electro-membrane technology based on electrochemical process using electrical energy for the production of chemicals. The process can be used for concentrating, extracting, separating products, modifying molecules, purifying solutions, pH adjustment and regenerating salts into their base and acid. This paper reviews the principle of ED, present some of the different options and discuss applications that are relevant to the hydrometallurgy and mining industries for the treatment of effluents focusing on recovery of chemicals (acid and metals) and recycling of water minimizing the environmental footprint.INTRODUCTIONElectrodialysis (ED) is usually defined as an electrochemical separation process in which electrically charged membranes and an electrical potential difference are used to separate ionic species from an aqueous solution and other uncharged components [1]. ED technology consists of an electro-membrane technology based on an electrochemical process using electrical energy for the production of chemicals. It is a method combining electrolysis and dialysis was proposed for the first time in 1890 by Maigrot and Sabates [2]. In the late 1930s Teorell, Meyer and Sievers discussed membrane phenomena, revealed membrane potential, electric conductivity, transport number [3]. Meyers and Strauss introduced a multi-compartment ED apparatus consisting of two electrodes and a stack of ion-exchange membranes between them [1]. They succeeded to double the concentration of a KCL solution [3- Tarleton]. In general, ED consumes less energy than electrolysis to perform salt splitting. In that regard, one can expect an energy reduction of about 30% [4–5]. ED offers a great versatility in the domain of separation processes. Indeed, it can be used for concentrating, extracting, separating products, purifying by desalination, pH adjustment and regenerating a salt to acid and base components. This paper reviews the principle of ED, presents various options available and discusses potential applications relevant to the mining and metallurgy industries with economics of some successful industrial applications."

Jan 1, 2016

By Jaeheon Lee

"Biooxidation of gold ores or concentrates could be a very attractive alternative to pressure oxidation (POX) or roasting to liberate the gold grains from various sulfides. Crushed heap bioleaching was successful in US and many operations using tank bioleaching of gold concentrate are currently running around the world. Many parameters need to be considered during the project of sulfidic refractory gold ore process. Capital and operation costs are among the most important ones. Run-of-mine heap biooxidation could be very inexpensive and the smaller the crush size (particle size), the more expensive the capital and operating costs for biooxidation application are expected. The capital cost of biooxidation could be a fraction of the cost for building POX plant or roaster and the operating cost could be 1/3 of POX or roasting depending on the method utilized. A new biooxidation process, Sand Farming, is introduced as an alternative to POX and tank biooxidation process. A relatively coarser particle size (P80 = 650 µm) of the process benefits the low cost of grinding against the conventional grinding size (P80 = 75 µm) for other options. The cost of Sand Farming is less than 40% of that of pressure oxidation with comparable gold recovery from the downstream process. This paper will review the laboratory scale testwork for various biooxidation process of sulfidic refractory gold ores and concentrates and provide the economic evaluation showing the biooxidation could be the most economic method without much sacrificing the overall gold recovery. INTRODUCTIONThe decreased availability and lower grade of raw materials has motivated industries to consider recovering values utilizing low cost process options. The process may treat high grade concentrates or submill grade ores that cannot be processed economically by conventional milling-flotation or leaching. Sulfidic refractory gold ores/concentrates have been economically processed by roasting, pressure oxidation, and biooxidation in stirred tank reactor. The process selection is based on a series of studies including multi-year long ore characterization and metallurgical investigations."

Jan 1, 2016

By J. C. Beidelman

One of the oldest settled portions of Canada is that "strip of land" extending into the Gulf of St. Lawrence, known as the Gaspe peninsula, with the Bay of Chaleur on its southern boundary. This "strip of land" is still so very sparcely populated that only at a few places does settlement extend more than a few miles from the coast. ? The peninsula is 160 miles long, 75 miles wide and with the exception of the above mentioned settlements is a mountainous wildness-void of all roads or inhabitants. Developments in the interior, of all nature, out-side of the cutting of timber by limit holders, was entirely lacking until the year 1915, when mining was first commenced. In the summer of 1844 Sir William Logan made a preliminary survey across the peninsula, from Cape Chat on the Gulf of St. Lawrence to Cascapedia on the Bay of Chaleur, passing through a country ?of which very little was known at that time. After a rather rough trip to the headwaters of the Grand Cascapedia river, Logan&apos;s party descended this river to its mouth, passing ten miles west of what is now known as the Federal mines. There is no record of Logan, or of any of his party, finding zinc or lead ores of any character on their journey across the peninsula, and until 1909 no precious or base metals were discovered within reasonable distance of Logan&apos;s survey.

Jan 1, 1924

By George E. Cole

"It is a truism that the metals, and particularly the precious metals tend to monopolize the attention of those interested £n the mineral industry. This is a tendency to be mildly, but actively and continuously combatted if we are to have a well-rounded mineral development." There are in the province of Ontario a number of industries centred about the non-metallic minerals. Too little is heard of the part these play in our industrial life. It is with the intention of showing what the gypsum industry is doing in Ontario that this paper is written. The writer lays no claim to any originality in the discussion and merely offers some material in an endeavour to assist in bringing about that &apos;well-rounded mineral development&apos; sought for Ontario. M. Y. Williams in his "The Silurian Geology and Faunas of Ontario Peninsula and Manitoulin and Adjacent Islands"1 in discussing the industries dependent on the Silurian rocks of south-western Ontario points out that "the splendidly ordered gypsum mine at Caledonia, formerly owned by the Alabastine Company of Paris, and now owned by the Ontario Gypsum Company, is a revelation to the average man, who disconnects mining entirely with this part of Ontario". This region is better known as one of the richest and most thickly settled agricultural areas in Canada.

Jan 1, 1925

By H. Yasuhara, N. Kinoshita, S. Nakashima, K. Kishida

"In this study, flow-through experiments in fractured rocks have been conducted under different stress, temperature, and pH conditions so as to understand the evolution of permeability induced by these conditions. Throughout the experiments, the confining pressures and temperatures are well-controlled. Effluent concentrations are also measured for the ten elements of Si, Al, K, Fe, Ca, Na, Mg, Ti, S, and Cl that are included mainly in the targeted rocks. In the early stage of the experiments, the fracture permeability measured abruptly decreases with time, and subsequently reaches quasi-steady state within a relatively short period. In contrast, the permeability in the intact rocks monotonically increases with time. The permeability increase and decrease are attributed likely to the relative dominance of mineral dissolution in the pore spaces and to that of mineral dissolution/crushing at the propping asperities within the fracture and/or mineral precipitation onto the free surfaces, respectively. The evolving rates and magnitudes of the permeability are likely to be controlled by the stress exerted over the contacting asperities, temperatures, and pH of the permeant. Thus, this complicated behavior should be attributed to the coupled chemically- and mechanically-induced effects, which should be examined in more detail for longer period to contribute to the safe entombment of radioactive wastes. INTRODUCTIONUnderstanding of the flow and transport characteristics of porous/fractured rocks is required for the safe and long-term geological isolation of energy-related by-products (i.e., high level radioactive wastes and anthropogenic CO2). Notably, under relatively high temperature and stress conditions, mechanically- and chemically-mediated processes may alter the pore structures in rocks, resulting in an irreversible evolution of the flow and transport behavior. Augmentation in permeability may result from mechanical dilation due to shearing and mineral dissolution within the pore spaces, while reduction may result from reversible or irreversible mechanical compaction, mineral dissolution at the contacting areas, and clogging of pore spaces by precipitation of secondary minerals."

Jan 1, 2015

By Sunil S. Gandhi

"The Mountain Lake deposit is a tabular sandstone-type uranium deposit, hosted by the basal unit of Middle Proterozoic Dismal Lakes Group. Uranium occurs mainly as sooty pitchblende disseminated in stratiform lenses within gently dipping quartzose sandstone. It is associated with copper sulphides, pyrite, hematite, and traces of nickel and cobalt arsenides and of silver.Exploration HistoryUranium showings on the PEC claim group were discovered during 1969 by an airborne radiometric survey carried out over the Dismal Lakes-Great Bear Lake area by Aquitaine of Canada Limited (Bizard and Salat, 1969). Some drilling was done in the vicinity of the showings in 1975 by the company under a joint venture with Eldorado Nuclear Limited but the results were not encouraging (Hassard and Woollett, 1975). During 1972, Trigg, Woollett and Associates Limited conducting surveys for Imperial Oil Limited, discovered numerous high-grade radioactive boulders scattered over a distance of several kilometres north and west of the showings, and the area north of the PEC claims was staked as the YUK claims (Ahuja, 1974). A systematic study of the boulder distribution and Pleistocene geology suggested a source additional to the showings. More intensive exploration followed, and in 1976 drilling just north of the PEC claim group boundary intersected the main deposit at a depth of 75 m to 150 m, beneath overburden up to 60 m thick. Part of the deposit extends into the PEC claim group which is under exploration by the Aquitaine-Cominco Joint Venture.The following brief description is based on the presentations in 1978 by F. Hassard of Trigg, Woollett and Associates Limited at the Geoscience Forum in Yellowknife, and by S.S. Gandhi of the Geological Survey of Canada at the Mineralogical Association of Canada Uranium Short Course in Toronto."

Jan 1, 1986