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By Jean-Marc Lulin

"Depuis 1906, près de 130 gisements ont été découverts dans la inture archéenne polymétallique (Cu, Zn, Au, Ag) du nord-ouest québécois. Une étude régionale du développement du potentiel inier est présentée puis détaillée pour quatre secteurs: Rouyn-Dranda, Val d'Or-Malartic, Bousquet-Cadillac et Matagami.L' analyse est conduite a l' aide des paramètres suivants: temps, méthodes de découverte, profondeur des gisements et poids métal. Les courbes cumulatives illustrant le nombre de gisements découverts fonction du temps montrent une forme générale en ""S"" dont les i'iations de pentes correspondent aux variations dans les taux de couverte. Initiation, réalisation et stabilisation des cycles de décourté sont ainsi mis en évidence. Deux ""bourns miniers"", de 1922 à 1945 et de 1955 à 1965, rassemblent 72 % des mines identifiées sqú à présent.La plupart des mines sont trouvées en subsurface: 90% ont leur mmet entre 0 et 100 mètres de profondeur dont 70 % entre 0 et 10 êtres. Dans le temps, il y a d' abord récolte par prospection puis par ophysique et enfin, développement progressif du potentiel en proeur avec des méthodes composites. Environ 80% du poids métal extrait de 4 camps miniers, couvrant 8% de Ia surface régionale quelques gros gisements dominent /a production.Ces données permettent de proposer une nouvelle approche pour analyse d' une région minière:La distribution de Ia profondeur des gisements en fonction du temps est indicatrice de la maturité d' un camp minier et peut servir a évaluer son potentiel résiduel.L’analyse des courbes en ""S"" permet d’extrapoler les taux de succès relies aux différentes méthodes et met en relief le rôle crucial de I' innovation dans I' exploration.ABSTRACTSince 1906, some 130 deposits have been discovered in the Archean polymetallic belt of northwestern Quebec. In this paper, the development of the mining potential is analyzed at the regional scale and for the following mining camps: Rouyn-Noranda, Val d'OrMalartic, Bousquet-Cadillac and Matagami.The analysis is based on the following parameters: time, discovery method, depth and weight of metal extracted. Curves showing the cumulative number of deposits discovered as a function of time are ""S"" shaped with slope variations corresponding to changing discovery rates. Initiation, realization and stabilization of discovery cycles are thus well represented. Two ""mining booms"", 1922 to 1945 and 1955 to 1965, account for 72% of the mines identified to date.Most exploitable orebodies have been found near the surface: 90 %have their top between 0 and 100 meters, including 70% between 0 and 10 meters. Early discoveries were made by prospecting, followed by geophysics while the progressive development of the depth potential is being realized by a combination of methods. Approximately 80 %of the metal extracted comes from four mining camps which cover 8% of the area, but most of the production can be allributed to only a few large deposits. Based on these data, a new approach to the analysis of a mining region is proposed:1) The distribution showing deposit depth versus time is indicative of the maturity of a mining camp and can serve to evaluate its remaining potential.2) The ""S"" curve analysis can be used to extrapolate the success rate of a specific exploration method and also stresses the crucial role of innovation in exploration."

Jan 1, 1989

By Gordon Jackson

"There are two accomplishments of air and gas drilling: a new series of economic and mechanical challenges; and, acceptance as a standard drilling and completion tool.The new challenges are related to the concept of using a gaseous circulating medium in drilling for oil or gas. For purposes of discussion, a two part division has been made: the challenge of fluid invasion control and that of equipment and tools. Great strides have been made in the development of materials and techniques to combat formation fluid invasion. Chemicals and the ""mist drilling"" technique, now in use, have the versatility to cope with a wide range of downhole fluid entry conditions.Equipment and tools have been developed to meet the challenges of better, more economic drilling and completion possible with a gaseous circulating fluid. Economic and operational challenges remain.Acceptance of air and gas drilling as a normal operating tool was reached with difficulty. It is now established as a means of reducing costs in exploratory and develop-mental well drilling, exemplified in a recent study of 226 wells covering 419,407 feet of hole in the United States. Air reached the projected depth in 85 per cent of the operations, although formation water was encountered in 48.7 per cent of the holes. Slim hole bit performance and cost all compared for overall bit averages as part of analysis."

Jan 1, 1961

By J. Desrosiers

"Minnova Inc. has five operating divisions thoughout Canada. One of them is Lac Dufault which was established in 1964.Lac Dufault is located 15 km north of Rouyn-Noranda, in what is known as Noranda volcanic centre, in northwestern Quebec. For more than 25 years, Lac Dufault has produced copper, zinc, gold and silver from four different mines: Norbec, Millenbach, Corbet and now Ansil.Ansil, officially in production since July 1989, is one of the deepest mines presently in production in Quebec. This high-grade copper, gold, zinc and silver orebody is being mined at a rate of 1200 tonnes per day with a total workforce of 200 employees.Of particular interest are the high mechanization level of the underground mine, technical innovations also underground, and computer applications throughout the division.IntroductionMinnova Inc. was formerly known as Corporation Falconbridge Copper until 50% of its shares were bought by Kerr Addison Mines Ltd . in 1986 and it became a member of Noranda Group of Companies.Minnova stands for mining innovation. It means Minnovaaims to use state-of-the-art technologies in mining and exploration to achieve maximum efficiency and cost effectiveness. It also means that they aim to use both proven and innovative management principles to the optimum benefit of their employees and shareholders. Minnova has operations across Canada. Presently four mining divisions produce copper, zinc, gold, silver and lead. Two are situated in Quebec: Lac Dufault (established in 1964) and Lac Shortt (established in 1985); one in Ontario; Winston Lake (established in 1988); and one in British Columbia; Samatosum (established in 1989).Minnova has an annual exploration budget of $15 million divided 60/40 between base metals and precious metals. Most of Minnova's exploration efforts are concentrated around their existing mines. Exploration is carried out from six regional offices located at Rouyn-Noranda and Chapais in Quebec; Thunder Bay in Ontario, Vancouver in British Columbia, Reno, Nevada in the United State and Panama City Panama. Each of the Canadian offices maintains close liaison with nearby operations.Lac Dufault Division is located in the Noranda mining camp, approximately 15 km north of the city of Rouyn-Noranda, in northwestern Quebec (Fig . 1)."

Jan 1, 1991

Of the many organic impurities present in Bayer liquor, sodium oxalate is known to have one of the most detrimental effects on the Bayer process. Because of its limited solubility, it will co-precipitate with gibbsite during the precipitation stage which results in many operational challenges for the refinery. Despite the importance of this phenomenon, the interaction mechanism between gibbsite and sodium oxalate is not well understood. In this study, the growth of sodium oxalate on three main morphologies (random agglomerates, prims and hexagons) of water-washed and caustic-washed gibbsite was observed under synthetic Bayer conditions using in situ optical microscopy. After a short induction period, oxalate started to nucleate on gibbsite crystals, and grew with a needle-shaped morphology which eventually developed into oxalate bundles. In addition, the results indicated that caustic washing was able to partly decompose gibbsite crystals and thus make the gibbsite surface rougher, which provides more potential sites for oxalate nucleation and growth. The growth rate of oxalate crystals on the basal (001) face of water-washed gibbsite was 1.33 µm/min determined by the time-lapse imaging of in situ optical microscope.

Jan 1, 2014

By T. Banerjee, Y. Dumais, R. Lemire

"Agnico Eagle LaRonde produces over 300,000 ounces of gold annually, along with silver, zinc and copper by-products. The LaRonde plant consists of a conventional SAG and Ball mill circuit, followed by flotation. Load management is imperative for maintaining stability in grind size and ensuring consistency of the flotation feed. In flotation, the mass pull profiles of the cells and reagent dosage rates need to be managed to maximize recovery, while maintaining product quality. This is achieved by controlling the air, level and reagent addition set-points across the circuit. However, disturbances such as feed size distribution, ore hardness and mineralogy make it challenging to maintain efficient control using traditional control techniques. LaRonde therefore worked to develop a progressive control strategy, targeting stability and optimization. This started with a year-long instrumentation upgrade campaign, focusing on optimizing the performance and reliability of plant-wide instrumentation. The process was then optimized, leveraging AwaRE advanced controllers running in closed loop with PARC modules embedded within the PLC. The installation of 8 PFC cameras in flotation changed the flotation operation from a level and air control based strategy, to one that controls mass pull. This new control philosophy has allowed the plant to effectively manage mill load, improving grind size and providing increased throughput with better flotation performance.INTRODUCTION Background Since 2015, Agnico Eagle LaRonde has been conducting an optimization campaign to maximise the performance of plant assets leveraging instrumentation and control. The grinding and copper flotation circuits were identified as the areas having the greatest opportunities and value proposition for advanced control. A disciplined approach was followed to design and implement a progressive control solution to achieve operational excellence."

Jan 1, 2018

By R. Amata

"The Gakara Rare Earth deposit in Burundi (East Africa) is unique for its high grade (e.g., 54.3% TREO on average) and low uranium and thorium levels. The majority of the light rare earth (RE) elements in material from Gakara are contained within the familiar RE minerals bastnaesite and monazite. Extensive metallurgical test work was conducted by SGS Minerals Services on mineral samples collected from the Gakara deposit. Various whole ore hydrometallurgical processing routes were examined in a scoping level test program. Preliminary beneficiation testing was also conducted, though it was determined that only marginal upgrading would be achieved with significant RE losses. Thus a hydrometallurgical process on whole ore was developed to minimize the overall process complexity and achieve maximum RE recovery. Results from the test work will be presented, along with the selected base case flowsheet involving agitated atmospheric sulphation of the RE minerals, RE double sulphate precipitation, caustic conversion, redissolution, and carbonate precipitation. Following the base case flowsheet, a purified cerium free mixed RE carbonate with low levels of radioactive elements was produced.INTRODUCTIONRainbow Rare Earths Limited (Rainbow) is a mining company engaged in the exploration and development of the Gakara rare earth deposit in Burundi; Figure 1 shows the project location. The project is located in the Bujumbura Province and 45 km from the Burundi capital of Bujumbura. Notable for its exceedingly high in-situ grade – 54.3% on average total rare earth oxide (TREO), low uranium and thorium levels and familiar rare earth minerals, bastnaesite and monazite – Gakara is the world’s richest rare earth deposit. The project, a previously operating mine from 1948–1978, has a significant mineral inventory base, a long life of mine, well understood mineralogy, and robust economics. Rainbow is focused on bringing Gakara into production in the near term, ramping up to produce 5,000 t/y of a 54%+ TREO concentrate."

Jan 1, 2016

By B. Yu, S. Kelebek, C. Gibson, M. Aghamirian

There are a number of high grade niobium deposits worldwide which have been deemed untreatable by flotation due to the very fine grained nature of the in situ pyrochlore, the primary niobium bearing mineral. A known method of recovering extremely fine particles is through the use of chelating reagents such as hydroxamic acids which have a strong affinity for transition metals. However, one of the major issues in the flotation of niobium bearing minerals using hydroxamic acids is the corresponding recovery of other transition metal gangue minerals including magnetite, hematite, and pyrite. In order to better understand the differences in behavior of niobium and iron bearing minerals in flotation with benzohydroxamic acid (BHA) and sodium hexametaphosphate (SHMP) at a range of pulp temperatures, a Box-Behnken experimental design was employed. Regression models for the global recovery of iron indicated that iron mineral recovery was significantly influenced by both BHA and SHMP dosage. Upon examinination of flotation products by semi-quantitative XRD, it was observed that recovery of iron oxide and sulphide minerals (hematite, magnetite, goethite, and pyrite) was problematic at high benzohydroxamic acid dosage, while sodium hexametaphosphate was mainly helpful for carbonate mineral depression. Iron rich carbonates (likely an iron rich dolomite) largely reported to the tails with increased SHMP dosage.

Jan 1, 2015

By M. W. Airth

ON THE 6TH JULY in the year 1953 an announcement was made to the public that touched off one of the greatest staking rushes in the history of mining in Canada and resulted, in tl1e space of a few short years, in the development of the greatest reserves of uranium-bearing ore in the world. It was ?On this date that the famous "Blind River back-door staking bee" was completed with the acquisition of some 2,000 claims by the Preston East Do me-Technical Mine Consultant teams under the direction of Mr. Franc Joubin and Mr. Robert C. Hart. That story has been told from coast to Coast and is too well known now to re-quire elaboration. Suffice to say that, in the short elapsed time of less tl1an five years from that momentous summer of 1953, three of the Algoma mines are in full production, three more are rapidly nearing full production, five more 1are approaching the production stage, a new hard-surfaced highway, 108, has been built to serve the area, and a brand new, completely planned city, Elliot Lake, is being built to provide the amenities of living to the 22,000 people already in the area.

Jan 1, 1958

By G. H. Robbins

"Originally presented at TORONTO 94, CIM-AGM, this paper has been updated to reflect the present status of business development for theSO2/AIR process. The paper reviews the back-ground leading to the invention, discusses the process chemistry and historically tracks the commercial development. Engineering and cost considerations are presented.IntroductionThe year 1994 was particularly significant in terms of the technical and business development of the INCO SO2/AIR cyanide destruction process. The year marked a decade of service to the world mining community since INCO acquired the Canadian patent in 1984. In that time period, the technology had become widely recognized as the state-of-the-art process in the field of cyanide detoxification and today we enjoy the distinction of having licensed the process at over 50 project sites worldwide. The application for the process has mostly been in the mining industry in precious metal recovery plants where it offers treatment for a wide range of waste streams such as: CIP/CIL slurries, Merrill-Crowe barren bleed solutions and/or re-pulped filter cakes, tailings pond water recycle or discharge, make-up water to flotation circuits and feed to underground backfill plants. The process also applies to the treatment of high cyanide rinsewaters from metal plating shops. More recently the process is being applied to the rinsing and abandonment of heap leach pads where it has proven to be a very cost-effective application of the INCO process. The distinct advantages that have led to the success of the process are the ability to work on slurries as well as solutions and the significantly low cost of sulphur dioxide products. The process is safe and easy to manage and uses all forms of SO2(liquid, gas or salts) which gives the process tremendous versatility with respect to geographic application. Having more than ten years of service"

Jan 1, 1996

"The outlook for Eastern Canada is decreased coal production and for Western Canada increased production. The market for Western coal is expected to reach 40 million tons per year in metallurgical and thermal-power markets.Technical developments in Eastern Canada include successful methane drainage experiments, modifications to the shearer-loader to improve cutting rates, mechanized mining of a tail-gate stable and mechanical stowage of level brushing. In Western Canada, the most modern equipment is used in mining, beneficiating and shipping coal. Underground hydraulic experiments were started in 1969. The importance of reclamation was recognized and plans have been made to re-vegetate disturbed areas and mine dumps.The Mining Research Centre closed the field office in Nova Scotia and is preparing to open a new field office in Calgary, Alberta."

Jan 1, 1970

By L. C. Stevens

The particular purpose of this paper is to direct attention to the development of underground conveying as applied to methods of working coal in the mines of Alberta. Historical A retrospective view of coal mining discloses a continuous effort, on the part of those interested, to substitute mechanical contrivances for hand labour. A patent for a coal-cutting machine was granted to Michael Menzies in 1761, at which time much of the transportation of coal underground was accomplished by means of sledges. Early forms of cutting machines attempted to duplicate the action of a miner's pick, and one hundred years lacer than Menzies? patent we still find this class of machine, driven by water power or compressed air, in use to a limited extent. A coal-cutter using the principle of a circular saw and worked by hand was exhibited in London in 1851, and from these crude beginnings the machines of today have been evolved. Transportation of coal underground has similarly been subject to considerable improvement. The above mentioned Michael Menzies took out a patent in 1750 covering the use of a self-acting incline plane, which is probably the earliest record of any system devised to lighten the load of the crammer or car-pusher of those days. In the year 1868 the Gillot & Copley machine was patented, this being a compressed-air-driven disc coal-cutter which proved highly successful. The chain cutters were a natural development from this type, and for a number of reasons they have been even more successful in the majority of cases.

Jan 1, 1930

"Real time analysis of conveyed bulk materials can be used to improve process performance by reducing variability and upgrading ore quality through selective removal of increments of flow that do not meet appropriate selection criteria. This paper focusses on proven Prompt Gamma Neutron Activation Analysis (PGNAA) and microwave transmission technologies used to representatively measure conveyed ore quality in real time so that meaningful decisions can be made between the mine and mill. This enables the effective removal by bulk diversion of small increments of conveyed flow such as waste, highly deleterious material or sub-economic material from the mill feed. Improved ore quality in plant feed optimises process performance, reduces processing costs and minimises tailings generation. Analysis is unaffected by particle size, dust, layering or segregation, mineralogy and belt speed. Technologies are explained and performance examples given from installations in copper and iron ore. The technology has been used successfully in bulk sorting for over twenty years typically using measured increments of a few minutes. Improvements in technology and calibration performance have resulted in accurate measurements over increments of thirty seconds and below.INTRODUCTION Ore quality variability exists on a number of scales. Block model grades represent a few hundred to many thousands of tonnes. Grade control at the mine occurs on a scale typically down to the size of a haul truck, which may be a few hundred tonnes. Highly variable ore quality is detrimental to process efficiency and effectiveness. Processing waste or low grade ore when higher quality feed is available represents a lost opportunity to generate higher revenues earlier in the operational life. Measuring ore quality accurately over short time increments during conveying enables small increments to be measured and diverted according to their quality. The paper explains the technology and benefits. Neutron irradiation techniques were considered potentially suitable for conveyed bauxite measurement by Beurton et al, 1995. Tran & Evans (2001) concluded there was no equivalent technology to Prompt Gamma Neutron Activation Analysis (PGNAA) in terms of material penetration power. PGNAA was evaluated by Nelson & Riddle (2003) for possible use in the phosphate industry and recommended its use for further characterisation of the mine’s various ore types to improve stockpile allocation and grade control. Cottle (2007) discussed test work for an iron sinter application and Delwig et al (2011) described the successful installation in 2009 and performance of PGNAA for base-to-acid ratio control in sinter feed with the analyser output used to control lime addition. Geoscan (PGNAA) works very well on iron ore and can “improve control over what is happening in the plant” and that comfort can be provided in knowing that the product is on-spec according to Minnett (2010). PGNAA is not yet used in the minerals sector for tariff purposes as has occurred since 2000 with Coalscan (PGNAA) in coal (Minnett, 2010)."

Jan 1, 2017

By A. H. Ransom, M. E. Robb

The Salmita Gold Mine is located 240 air kilometres northea t of Yellowknife on the east shore of Matthews Lake. Salmita is one of several gold showings which are regionally associated with the steep easterly dipping contact zone between mafic, intermediate and fe lsic volcanics to the west and overlying finely laminated argillaceous sediments to the east. The volcanic assemblage forms a narrow 2 m to 7 m wide north to northwesterly trend ing Belt of Yellowknife Supergroup Archaen greenstone rocks. The contact zone exhibits exhalite character and the increased sulphide content provides a di stinct VLF-EM , IP/Resisti vi ty and/or magnetic signature. Gold occurs at or near this contact in three main settings: associated with si liceous vein-like structures; with finely disseminated sulphides within ericitic altered upper fe lsic tuffaceous unit ; or with quartz in narrow shear zones within the overlying sediment . The B-Vein is of the former type with free mi ll ing gold occurring within a highly sil iceous zone having an average widtn of 1.69 m. Alteration is intense within the immediately su rrounding host lithologies and includes the development of si lica, carbonate, sulphide, sericite and chlorite with minor graphite, epidote. tourmaline and scheelite. The mineable zone above the 4th level (-200 m) ha an average strike of 160 m and is divided into three south plunging ore shoots separated by the regional Salmita Shear Zone in the south and by a low-grade structural hiatus in the north. Production from the B-Vein commenced in August 1983 based on a diluted in situ ore reserve of 140,000 t grading 26.6 git Au . As of December 31, 1985, a total of 131 ,537 t grading 27.8 git Au have been mined at a ra.te of 160 t per day and a 96.4 percent recovery, to produce 3,522 ,000 g (113,227 ounces) of gold . Current (January I, 1986) reserves total 45,500 t grading 37 g/t Au down to the 10th level (-500 m) .

Jan 1, 1986

By Lloyd Buckingham

Barrick Gold Corporation (Barrick) has undertaken innovative methods of evaluating and improving the performance of grinding mills in several of its operations around the world. The results have been positive with some of the mines showing more than 20% net energy improvement leading to more than 43,000 tonnes per year reduction in CO2 emissions in four of the operations reviewed.

Jan 1, 2012

By V. Panayotov, M. Panayotova, R. Villas-Bôas

The "United Nations Framework Classification (UNFC-2009) for Fossil Energy and Mineral Resources 2009” is the international system designed to meet (to the extent possible) the needs and to support the decision making and resources management of private industry investment, governments, policymakers, bank investment, scientists. There are different international and national systems classifying commodities (resources, reserves, possibility and feasibility to extract them, etc.) with their own definitions and reporting terminology which often do not overlap entirely or even differ significantly - thus creating difficulties and problems among stakeholders to understand each other. The UNFC-2009 is developed to allow “speaking in one language”. The paper presents briefly the UNFC-2009. The UNFC-2009 applies simultaneously three fundamental criteria to classify projects: economic and social viability, field project status and feasibility, and geological knowledge (so called E, F and G axes), thus creating a visualized, easily understandable three dimensional system. The E, F and G axis categories are divided to subcategories, using additional criteria. The UNFC-2009 is already applicable to solid minerals, nuclear fuel resources, petroleum. The amounts of solid waste generated by metals production from ores (mining, minerals beneficiation, extraction metallurgy) and its metals content are discussed from the viewpoint of using the waste as resource. An attempt is made to apply the UNFC-2009 to technogenic waste from metals production from ores - both to old engineering constructions (historic mining dumps and reclaimed beneficiation tailings ponds) and new (currently in use) dumps and ponds.

Jan 1, 2016

By K. Howard Poulsen

Shear zones are tabular tructures which tend to occur either discordantly within, or concordantly along the margins of, competent rock masse uch as plutons, sill or flows. They contain deformed equivalents of their host rock and are common sites for gold mineralization localized in tructure oriented y tematically relative to the shear zones and internal linear fabric. Apan from genetic implications, hear zone analysis proves useful in exploration for this type of deposit because the zones are generally wider and more continuous than associated mineralization and because there is an element of predictability to mineralization geometry (i.e. vein orientation. plunge).

Jan 1, 1986

By H. J. McQueen

About 1973 the abrupt decrease in crude oil shipments due to political action by Middle Eastern suppliers, caused a shortage and a steep price rise. In response, Canada had to develop strategies of diminishing consumption and increasing production in both traditional and environmentally friendly resources. To clarify the situation in Canada, there are brief histories of energy (discovery, pipelines), manufacturing and science development, 1800-1970. Energy strategies, both nationally and in Quebec, succeeded in curbing consumption and in expanding production while fostering research in renewable sources. The industry-sector committees provided free exchange of conservation techniques through the federal energy ministry, with progress reports issued annually. Pipeline history in North America is reviewed along with manufacture and construction plans in Canada. Considerable success in all the aspects provided long lasting benefits, but after the embargo was lifted, many research initiatives were gradually abandoned for political reasons. Sustainability is the goal; society must conduct conserver analysis, legislation and action to enhance it.

Jan 1, 2015

By Edward S. Bell, Frank Angebrandt

"Nuclear reactors must have very large heat outputs to compete with conventional sources and the only feasible applications are in the production of electric power or large quantities of process steam. This paper considers alternative fuels for electric power generation in Canada. In a publicly owned utility, nuclear stations are economic for base-load generation for unit sizes of 500 mega• watts or larger where competitive fossil fuel costs are higher than about 30 cents per million Btu. In British Columbia, Alberta and Saskatchewan, fossil fuels will continue to be in adequate supply at costs lower than 30 cents per million Btu and thus, except for the special case of Vancouver Island, power generation in Western Canada will continue to be the hydraulic and conventional thermal type. In Eastern Canada, fossil fuel prices are likely to be higher than 30 cents per million Btu and most utilities will be able to install units of 500 mw or larger, so that nuclear power plants will provide much of the base-load generation required. Base-load generation comprises about two-thirds of the energy generated by power utilities. By 1990, the total annual electrical energy load will be over 600 billion kwh, with two-thirds of this load in Eastern Canada. Allowing for additional hydraulic resources which may be developed in Quebec, British Columbia and Manitoba, hydraulic generation is forecast to provide a little more than a third of this electrical energy, nuclear generation a third and fossil-fuelled generation about a quarter."

Jan 1, 1969

By S. W. Marcuson, P. J. Mackey

The Canadian non-ferrous mining and metallurgical industry has made great strides in environmental protection during the past half century. The path taken by the copper-nickel smelting industry in reaching today’s level is traced in this paper. Following the practice at early copper smelters in Wales and in the US, Canadian smelters originally used tall stacks to disperse furnace of-gases. This was the normal mode of operation and was accepted by society and by Government. Gradually, Government regulations required fixation of sulphur dioxide emissions and Canadian companies responded with significant technical developments to achieve this result. The initial development in Canada of the first new technologies such as the Cominco Flash Suspension Roaster and the Freeman Flash Smelting Process - both representing early versions of the modern established flash smelting technologies - and then later technologies such as the Inco Flash Smelting Process and the Noranda Process, both of which continue to this day, are discussed in this paper in terms of their contributions to the development of environmentally friendly plants. The evolution of these and other technologies is also discussed. Some comments regarding how the industry will face the future are also included.

Jan 1, 2015

By Dale Verran, Jared Orynik, Chad Sorba, David Bronkhorst

Denison Mines Corp. (“Denison”) has a 90% interest in the Wheeler River Uranium Project (“Wheeler River”) located along the eastern edge of the Athabasca Basin in northern Saskatchewan between the Key Lake mill and the McArthur River uranium mine. The project is host to the high-grade Phoenix and Gryphon uranium deposits, discovered by Denison in 2008 and 2014 respectively, which include combined Indicated Mineral Resources of 132.1 million pounds U3O8 (1,809,000 tonnes at an average grade of 3.3% U3O8). The Pre-Feasibility Study (“PFS”), completed in accordance with NI 43-101 in September 2018, is highlighted by the selection of the In-Situ Recovery (“ISR”) mining method for the development of the Phoenix deposit, with an estimated average operating cost of $4.33 (US$3.33) per pound U3O8. Phoenix is the highest-grade undeveloped uranium deposit known globally, including Indicated Mineral Resources of 166,000 tonnes at 19.1% U3O8 for 70.2 million pounds U3O8. The paper aims to provide a summary of Wheeler River and an overview of the proposed development of the Phoenix and Gryphon deposits according to the PFS completed for the Project. Further details regarding the PFS, including additional scientific and technical information are described in greater detail in the NI 43-101 Technical Report titled "Pre-Feasibility Study for the Wheeler River Uranium Project, Saskatchewan, Canada" dated October 30, 2018 with an effective date of September 24, 2018. A copy of this report is available on Denison's website and under its profile on SEDAR at www.sedar.com and on EDGAR at www.sec.gov/edgar.shtml.

Jan 1, 2020