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By Jianglan Duan, Steve L. Cockcroft, Andre B. Phillion, Carl Reilly, Daan M. Maijer

"In the aluminum alloy wheel casting process, careful design of the cooling system in the die and its operation (cooling channel timing) are critical to achieve quality and productivity goals. The problem is challenging owing to the cyclic nature of the process and the relatively large thermal mass of the die in comparison to the wheel. For a given die geometry, a set of constraints have been defined to ensure directional solidification and an objective function, based on cooling rate during solidification, has been defined to reach a target secondary dendrite arm spacing. The methodology presented in this study employs the commercial finite element package, ABAQUSTM, and an optimization module based on the open source library, Scipy. The developed methodology has been applied to a series of geometries and cooling system configurations, including a 2-D axisymmetric wheel and die assembly generated from a prototype die. Preliminary testing has shown that careful selection of the objective and constraint functions have made it possible to reach desired solidification pattern.TM- Dassault Systèmes Corp."

Jan 1, 2014

By C. T. Harper, B. J. Fryer, R. P. Taylor

"IntroductionThe Maurice Bay deposit is one of a number of uranium deposits that have been found in recent years in the Athabasca Basin of northern Saskatchewan (Tremblay, 1982). This deposit, along with the others, belongs to the unconformity type deposits (Beck, 1977). They are, for the most part, polymetallic, being characterized by a suite of metals which include U, Ni, Co, Cu, Pb, Zn, Mn, V, Ag, Au, Pt-group elements, S, As, Bi, Se, Te, and Mo, some of which, besides U, are present in economic concentrations (Amok, 1974; Ruzicka, 1975; Tapaninen, 1976; Hoeve and Sibbald, 1978; Dahlkamp, 1978). The Maurice Bay deposit was known to be a small low grade deposit in which the ore was essentially monomineralic, consisting mainly of pitchblende (Harper, 1978). However, the occurrence of trace amounts of some of the elements common in the larger polymetallic ore bodies (e.g. Key Lake, Cluff Lake D) was anticipated. Thus a lithogeochemical sampling project was undertaken in 1979 across part of the Maurice Bay deposit (Harper, 1979). Major oxides (SiO2, Al2O3, FeO, Fe2O, MgO, CaO, K2O, Na2O, MnO, P2O5, and TiO2) and a group of the most common trace metals (U, Ni, Co, Cu, Pb, As, Au, V, and Se) were analyzed to determine whether any elemental patterns (halos or depletions) could be detected which would reduce the number of pathfinder elements needed for exploration purposes. In addition to the above metals, Th was also checked because some conglomerate strata in the Maurice Bay area are known to be thorium-enriched (Harper, 1978). Only the trace metal distributions will be discussed in detail in this report.General GeologyThe Maurice Bay area is underlain by three major groups of rocks, the White Lake metamorphic complex, an unnamed granodiorite complex, and the Athabasca Group, described previously (Fig. 1; Harper, 1979). Table 1 summarizes the stratigraphic features as deduced by geological mapping and the examination of drill cores."

Jan 1, 1986

By E. A. Lowe, J. W. Smith, C. W. Overton

"The operations of Bethlehem Copper are situated in the south-central interior of British Columbia at an elevation of 4900 feet above sea level. Main road and rail transportation systems pass through Ashcroft in the Thompson Valley, which is 28 miles by road from the minesite. The operation was the first low-grade open-pit porphyry copper mine in British Columbia.The minerals are chiefly chalcopytite and bornite, while the rock is principally feldspar and quartz. In the outer fringes of the orebodies some pyrite is present. Average grade of mill feed is 0.55% copper.History of Milling Operations Production commenced in December 1962 at a rate of 3,000 tpd in a plant that comprised two-stage crushing followed by rod and ball milling. Production ratings were increased to 6,000, 10,000 and 12,000 tpd by the addition of a further stage of crushing and more rod and ball mills. When the last expansion was completed tonnage throughput exceeded the 12,000 ton designed rate and was stabilized at 15,500 tpd.However, recovery did not meet expectations at the expanded rate because of coarse flotation feed. Capacity in the rod mill circuits exceeded the subsequent fine grinding capacity, resulting in poor liberation. Studies were initiated to improve recovery without decreasing throughput.Description of Operation Prior to Pebble Milling Crushing with primary, secondary and a closed tertiary stage proceeds at a scheduled 20.5 shifts per week. Fine ore screened on 1/2"" x 4"" apertures is stored in a 30,000-ton bin ahead of two 12.5' x 15' rod mills. Rod mill discharge joins secondary ball mill (one 10.5' x 14' and one 11' x 14') discharge for classification in a single 50"" cyclone which closes the secondary mills. Overflow from this cyclone is split between three third-stage ball mill-pump-cyclone circuits (two 11' x 14' and one 12.5' x 15'). Prior to addition of the two pebble mills the flotation feed was produced by this three-stage grinding system. Grinding criteria are shown in Table I."

Jan 1, 1975

By L. Betteridge, A. Marks

"An OK 300 cu. ft. Skim - Air cell was installed at the HBM&S concentrator in Flin Flon in 1987. Since that time, 3 additional OK Skim - Air cells have been installed in HBM&S concentrators. The cell treats a coarse 70% solids slurry with a residence time of 2.5 minutes. The product from the cell (a unit cell type application) is a final grade copper concentrate with high precious metal values. Since its installation, the cell has improved gold recovery by 10 - 15%. Process variables such as circulating load, pH, froth depth, feed size, and reagent additions all have an effect on the operation of the cell. Maintenance on the cell has been minimal. Initial operating problems involving level control have been significantly reduced and operations are now relatively trouble free. Although very successful at Flin Flon, site specific operating circumstances will determine the suitability of this cell. INTRODUCTIONHudson Bay Mining and Smelting operates four concentrators in Northern Manitoba. Three treat copper-zinc ores, the fourth mills a copper-nickel ore. The Flin Flan concentrator operates two circuits in parallel which treat copper and zinc ores from the Trout Lake and Callinan mines. Both circuits in the Flin Flan mill have Skim-Air cells integrated into the grinding circuits.The Trout Lake cell was installed first and had a payback period of a few months. Required modifications to the cell were made to enhance its performance. These included changing the discharge valve size, tuning the level controller, and installing an insert into the rubber valve sleeve to increase its wear life. The payback period on the Callinan cell was significantly reduced because these modifications were completed prior to its installation.The cells produce a final grade copper concentrate and since their installation gold and silver recoveries to the final copper concentrate have increased significantly. Operating parameters such as coarseness of cell feed dictate the metal recoveries and froth depth determines the selectivity of the cell and therefore the grade of the concentrate.The Skim-Air cell can be suitable in applications where a final product is generated. However, when a bulk concentrate, which requires further separation, is produced, the coarseness of the product may not make it amenable to conventional flotation.The Flin Flan mills Skim-Air cells have worked exceptionally well with little maintenance required."

Jan 1, 1991

By K. Fagerlund, L. Rosenback, T. Mäkinen, Y. Anjala

This paper deals with the nickel smelter and refinery concepts Outokumpu has applied at Harjavalta and several other plants. Also other process routes and modifications developed and tested by Outokumpu during the recent years are highlighted. Outokumpu started nickel production in Harjavalta in 1959. Until 1995 the Flash Smelting - Peirce-Smith (PS) converting route was applied. High grade nickel matte from the converting step was further refined by means of leaching and electrowinning to produce cathode nickel. In 1995 the nickel production capacity was increased from 17 000 t/a to 52 000 t/a based on the Direct Outokumpu Nickel Smelting Process (DON). In the DON process PS converting is eliminated and high grade nickel matte with low Fe-content is directly produced in the flash smelting furnace (FSF). Metal values from the smelting slag are recovered in the electric furnace (EF) as iron containing Ni-matte. The DON process can be operated with either two matte concept, where high grade FSF matte and EF matte are produced, or a single matte concept, where EF matte is recycled to the smelting furnace and thus only one type of high grade matte is obtained. The additional refinery capacity at Harjavalta is based on hydrogen reduction producing.

Jan 1, 2005

By Angus D. Campbell

"IntroductionThe subject assigned to me tonight gives unlimited scope. The material available is so voluminous and leads into so many ramifications, and the memories of the Camp are so vivid and treasured, that it is difficult to decide just what to use. Then, too, the geologists are the story-tellers of our tribe - I am only a hard rock miner.Members of the Cobalt Branch and Cobalters everywhere will agree without question that this Cobalt camp has been the greatest of all influences on Canadian mining. To those who do not know Cobalt, our opinion may seem prejudiced and our statement exaggerated.Be that as it may, discussion on this subject can be profitable, since it is worthwhile now and then to think on 'whence we came' and 'where we are going'.In the revival of interest in the Cobalt camp, we hope our guests may feel some of the old Cobalt Spirit, which has become the Spirit of the North.Visitors may even, while here, catch a glimpse of that whimsical little guardian spirit of the camp - the original goblin, the Kobold - for which Cobalt was named.While Kobold brings that good luck which plays so important a part in mining, he can have his evil moments, as in his original German home. There, when he made the silver disappear from their good ore, they cursed the grey ore, calling it Kobold.Although this little goblin bas frequently upset our best mining plans and geological calculations, be has played the game as well. He placed •some silver on the surface, and when he hid ~t at depth he left dues .for its finding. He has rewarded many who sought his treasure and is still rewarding those who have persevered and had faith in him. t:lis influence and that of Cobalt camp has probably had a greater influence on your work and your mining areas than you realize"

Jan 1, 1950

"This paper describes some of the methods and equipment used for fine milling of minerals, and gives particular attention to the Vibro Energy system.In addition, the paper describes a specific application in the gold mining industry. This is the 200 tpd plant built by Anglo American Corporation at the President Brand Mine in South Africa in 1985, now a division of Freegold. This plant treats a gold bearing pyrite flotation concentrate which is finely ground to 15 microns prior to cyanidation and carbon-in-pulp (CIP). l .0 INTRODUCTIONFree milling gold ores are those that yield acceptable dissolution and recovery of the gold following grinding to what can be described as normal fineness, frequently between 50% and 90% passing 74 microns.Increasingly, gold metallurgists are faced with ores that are refractory. The traditiona1 treatment route for refractory gal d ores and concentrates has been by roasting, but for environmental reasons this is becoming less acceptable, or in some areas of the world, totally unacceptable. New methods of treating refractory gold ores are being developed and applied in practice. These new methods include pressure and biological oxidation. Higher gold liberation can also be attained by increasing the fineness of grind, although with conventional systems there are economic limits to this.In flowsheet development and test programs on new deposits, a standard procedure is to establish the relationship between the grind and subsequent go 1 d extraction. The normal situation is that gold extraction increases as the ore, or concentrate, is ground finer. Typically, this relationship is as shown in Fig. l, where the incremental additional extraction is very small once an optimum, or economic, grind has been achieved. This generally app1ies whether the material is free milling or refractory. The limits to grinding are set by the type of equipment which is commonly in use, usually ball mills. These mills have the obvious advantage of high capacity, however, they are increasingly inefficient as finer grinds are required. In general, ball mills are used to reduce ore to some agreed percentage passing 74, or possibly 53 microns."

Jan 1, 1988

By S. Steinlechner, S. Wegscheider

"In the past, the metallurgical industry was most of the time dedicated on their main commodity, recovering base metals like zinc, copper or lead but leaving other valuable side elements in the generated residues. As a result, these accompanying minor elements, like gold, silver, indium or also PGMs can be found in the dumps of the corresponding industry. Because of political unrest, strikes, economic reasons or decreasing primary resources leading to a high supply risk, also those mentioned minor elements moved into the focus of the recycling industry. Therefore, beside the base metals, first of all the recovery of those minor metals would be of high interest contributing to the economic viability of recycling processes, although they occur in much smaller quantities in materials. In this context, residues from zinc industry, like leaching residues or precipitation residues show high potential to carry silver as well as indium next to lead and zinc. Therefore, the paper summarizes carried out thermochemical calculations investigating a possible recovery of silver as well as indium by volatilization and the influence of zinc and lead on this process. Based on these theoretical investigations with HSC, trials in lab scale were done verifying the obtained results.INTRODUCTIONHuge amounts of iron precipitate, mainly jarosite get landfilled every year although there is a high content of valuable metals in this residue beside iron. Nevertheless, jarosite has to be dumped due to the presence of contaminating heavy metals. The accumulation of these residues takes up massive land on the one hand but also causes a series of environmental problems in ecosystems on the other. Moreover, some toxic ingredients such as arsenic and cadmium can be dissolved in rain water and are therefore harmful to the health of the aquatic systems. (Erdem & Özverdi, 2011; ÖzverdI & Erdem, 2010) Approximately 0.5 t of dry jarosite accumulate in the production of 1 t of zinc by the hydrometallurgical zinc-winning route (Svens, 2010). Jarosite is a precipitation residue formed during the iron removal. In general, the iron already exists in the zinc ore which is why zinc ferrite builds up during the roasting step of the zinc ore. Zinc ferrite is only soluble in strongly acidic solutions and during the hot acid leaching step it gets dissolved while zinc and iron enter the solution. It is necessary to get rid of the iron because otherwise it would deposit on the cathode first due to its precious character which would be harmful in the zinc-winning electrolysis. Nevertheless successful investigations were done by adding chlorine to the jarosite to recover silver. These findings leads to another residue which occurs in huge amounts – electric arc furnace dust (abbreviated with EAFD) from the iron and steel industry. In 2013 the annual electric steel production reached about 451 million tons. Around 15-20 kg of EAFD is produced per ton of steel in an electric arc furnace (EAF), creating approximately up to 9 million tons of dust per year. (Grabda, Oleszek, Shibata, & Nakamura, 2014; World Steel Association) Next to elements like zinc, lead and iron, chlorine and fluorine are present in this dust. While galvanized steel plates in the scrap act as a source for zinc, casting powders, flame retardants and synthetic coatings are responsible for the chlorine and fluorine contents in the dust."

Jan 1, 2016

By Donald E. Wakefeld

"The pace at which mining will occur in Northern regions and Arctic lands will depend on the answers to a number of questions. Who are the local aboriginal participants? What land uses are they pursuing? What are their objectives? What is their understanding of the process of mining development? This paper will focus on the last question, communicating the process of mineral development to local aboriginal communities.IntroductionIn the environmental impact hearings for the BHP-DiaMet diamond mine, the smaller Dene Treaty 8 Nation argued for the settlement of its Land Claims as a pre-condition to development. However, the larger Dene Treaty 11 Nation were prepared to permit the mine to proceed on the basis that their people would receive benefits during the construction and operation of the mine.Wherever mining is the significant basis for tax revenues and economic development expectations may be encouraged beyond the realities of the situation. Izok Lake has been known for several decades as a significant mineral deposit but because of its size and the transportation costs involved, it is now a “frozen” ore body. The extent of its mineralization at current metal prices will not support the mining and processing costs without substantial government support for infrastructure and roads. At the opposite side of Canada, Voisey’s Bay clearly satisfies all technical criteria but, nonetheless, two Inuit groups, the Innu, and Métis, have all made LandClaims relating to the mine area.Contrasting the mineral deposits at Voisey’s Bay and Izok Lake emphasizes that the timing of production is dependent on factors such as the grade and amount of reserves, their market price, location and availability of government support. Nonetheless, it is this author’s thesis that given an economic orebody the next most important factor is good communications. It is his view that Arctic mineral development will occur quickly only where good communication has resulted in the trust and mutual respect necessary to implement the mammoth cultural changes required."

Jan 1, 1996

By N. M. Stubina, P. J. Lind

Barrick Gold is in the process of building several new mines and implementing new processes at existing mines for which metallurgical technology is of key importance. The roles of the company's Strategic Technology Solutions team and the Barrick Technology Centre are discussed within the context of their responsibilities within Barrick's Operations Support group. The paper will present an overview of the development of the technology centre from the former Placer Dome Research Centre to its current form supporting strategic technology, capital projects, and operating sites. Novel approaches to research and development will be presented as well as an overview of some of the technologies developed from bench-scale to pilot-scale, and beyond.

Jan 1, 2011

By E. Rezazadeh Azar

Dump trucks are the main mean for hauling earth material within and outside of the construction and open-pit mining jobsites. The real-time monitoring of the material transportation trips is beneficial for proactive equipment management, volume estimation, and productivity measurement. The traditional manual observation is tedious, non-real-time, and expensive; therefore remote sensing technologies, namely GPS and RFID, have been employed for this reason. Ordinary construction videos are another costeffective alternative to monitor dirt loading and hauling operations in real-time. A vision-based system has been developed to recognize and count hauling trips. This system has three modules including object detection, tracking, and action recognition. This system processes videos taken from access roads in which it recognizes dump trucks and then tracks them throughout the viewfinder. The action recognition module is designed to reject false alarms and also terminate tracking. This way, the system is able to count the number of hauling trips and also record the time between each trip. Several state of the art computer vision algorithms were employed to develop this system. Some of these algorithms were modified using spatiotemporal information to minimize the inherent errors of the vision-based methods. The experimental results showed considerable performance of the system for practical application in the construction and mining sectors.

Aug 1, 2013

By J. M. Whatley

"IntroductionFEW COUNTRIES equal Canada in the diversity of its mineral output, the range of size of its mine operations, and the extremes of climatic and topographic conditions under which its mining is carried out. Camps large and small are scattered over thousands of miles, some served by excellent communication lines, many in remote regions of the north. Common to most of the deposits is that they are worked by underground methods, and rely on adequate hoisting installations for the success of their operations.Hoisting in some form •pre-dates all other mechanical operations in mines and the hoist remains one of the most important pieces of equipment at the average mine. It provides the single line of communication along which must pass the men and materials to mine the rock, and in turn carry the ore to a place for refinement.Development of Mine Hoists in CanadaCanadian designed hoists were first built and •placed in operation about the year 1880 and have since developed in pace with the rapid growth of the Canadian mining industry. Early machines were all of the steam or compressed-air driven types, of light construction and driven by two duplex slide-valve open-frame type engines. As their application and size increased, designs became more rugged and more efficient."

Jan 1, 1955

By H. B. Farnam

"THE IRON ORE Company of Canada has been using do-it-yourself type explosives for three years. During the last 12 months we have used over 10 million pounds of ammonium nitrate-fuel oil explosives and either purchased or formulated one million pounds of slurried explosives.W e have been moving approximately one million cubic yards of stripping and ore per month and we expect our production rate to in-crease. Eighty per cent of our strip-ping and ore is soft enough to be blasted successfully with ammonium nitrate-fuel oil mixtures. Twenty per cent of our material is extremely hard and requires an explosive having greater strength than an AN-fuel oil mixture.W e had been using canned am-monium nitrate base explosives and TNT pellets to give maximum bottom loading density to fracture hard rock. As AN -fuel oil became widely used, it was apparent that other types of explosives could be formulated to fit our blasting requirements. Dr. M. A. Cook of the University of Utah was consulted regarding new explosives and together we developed the blasting slurries.Figure 1 shows a general view of one of our hard rock pits. The foot wall is on the right-hand side and this material is called iron forma-Figure 1.-General view of hard rock pitstion by our Company but is called 'Taconite by the operators on the Mesabi Range. This material runs 35 to 45 per cent iron and many pieces are hard enough to scratch glass. The formation is tilted at an angle of 55 degrees as can be seen in Figure 3.The bedding planes of this rock are about 24 to 36 inches apart and if the material is not well broken or fragmented, large chunks or slabs must be handled by the shovels which reduces shovel capacity and efficiency and increases maintenance costs."

Jan 1, 1960

By Geo. D. Furse

"The information that has accumulated regarding the geology of the McIntyre mine is the result of work by several geologists and, as might be anticipated, their conclusions have varied. The writer has been at the mine only a few years and due to wartime conditions has not been able to study and review the mine's geology as thoroughly as his predecessors. Where the writer's conclusions differ from those of previous authors, it should be noted that he has been unable to re-map all the workings in which flow contacts are exposed, but has endeavoured to describe the structure as indicated by the evidence he has been able to observe. He wishes to thank H. G. Skavlem and H. S. Robinson for their constructive criticism of this paper, and McIntyre Porcupine Mines, Limited, for permission to present it. A list of references is appended.The McIntyre mine is in the central part of the Pearl Lake section of the Porcupine gold area. It includes the ""bed of Pearl lake, twenty-two claims to the north of the lake, and the Platt Vet lot to the southeast. It is bordered on the west by the Hollinger and on the east by the Coniaurum property. The chief ore-bearing veins on the upper levels lie very close to the north shore of the lake, but some occur under the lake, and others of lesser importance are found to the southeast. The most important veins are Nos. 3, 5, 7, 10, and 25. Some of the veins extend into the Hollinger. on the west and others cross the east boundary into the Coniaurum. The total production since the commencement of milling in 1912 to the end of March 1947 has been $168,448,218 in gold and silver from the milling of 17,690,963 tons of ore."

Jan 1, 1954

By E. L. Martheleur

The use of electricity in coal mines dates almost from the time when it was realized chat it could be used to produce mechanical power. The first motor put in service underground was installed to drive a small pump nearly 40 years ago, and since then the use of electricity in mines has reached an extent undreamed of at that time. We now find its universal adoption in all the mining countries of the world. Great progress has been made in the development of mining electrical apparatus in the last decade, and excellent and adequate material is now available for the use of electricity underground. Although mining accidents, due to the use of electricity, are not frequent, the miner is justified in demanding chat all electrical apparatus for installation below ground be constructed with a greater degree of safety than that used on the surface. That this view is shared by the authorities of the different mining countries is evidenced by governmental regulations relative to the use, erection, and maintenance of electrical apparatus below ground. Those with which we are specially concerned are the regulations for the installation and use of electricity in the coal mines of Nova Scotia. The potential dangers of electricity in coal mines are: Shock or burns by contact from live parts. Shock or burns by contact with parts which, although normally dead, have become accidentally alive. Fire. Explosion of gas or coal-dust Explosion of apparatus.

Jan 1, 1928

By Ye Chen, Jianhua Chen, Xianhao Long, Qingxia Liu, Zhenghe Xu

"It is crucial to understand the mechanism of the collector interacting with the mineral surface in the presence of water molecules, which could influence the relaxation and electronic properties of sulphide mineral surface due to the proximity effect for narrow band gap of semiconductors. The adsorptions of three typical collector molecules (xanthate, dithiocarbamate and dithiophosphate) on the sulphide mineral surfaces in the absence and presence of water molecule have been simulated by density-functional theory (DFT). The calculated results show that the adsorptions of collectors on clean mineral surface in vacuum are not in agreement with the observed flotation behaviours. The presence of water molecules has a great influence on the adsorption of collectors. The analysis of density of states of the mineral surface atom suggests that the adsorption of water molecules could influence the electronic properties of mineral surface and consequently influence the adsorption between the surface and the collector molecule.INTRODUCTIONIn the separation of multi-metal sulphide ores, the selectivity of a collector is a key factor for the efficient recovery of the aimed mineral. Xanthate, dithiocarbamate (DTC) and dithiophosphate (DTP) are the most common collectors used in the flotation of sulfide minerals. Generally, xanthate exhibits powerful collecting property but lack of selectivity. While dithiophosphate and dithiocarbamate show the good selectivity in the lead and copper sulphide mineral flotation. The mechanisms of these collectors interacting with the sulphide mineral had been attracted many attentions and several mechanism based on experimental results had been reported (Chander & Fuerstenau, 1974; Fuerstenau, 1990; Raju & Forsling, 1991; Crozier, 1991; Bradshaw, Cruywagen & O’Connor, 1995; Guler, Hicyilmaz, Gokagac & Emekci, 2006). However, the micro-mechanisms of the selectivity of these three thiol collectors on different sulphide mineral surfaces are not fully understood."

Jan 1, 2016

By Margarete Kalin

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

Jan 1, 2005

By H. P. Jacobi

"The last 25 years have seen tremendous economic pressure placed upon the base metal processor. Industry has responded with technological innovations that have contributed to significant reductions in capital and operating costs. Major changes in processing machinery and philosophy are highlighted for the main unit operations of a base metal mill. Changes in our attitudes on what is environmentally acceptable are also discussed.INTRODUCTIONNewton's law of motion paraphrased states that nothing will change unless there is a pressure to do so.Aase metal processing as a primary commodity related industry has been under severe economic pressure over the last 25 years. This has been brought on by over capacity from new operations in the L.D.C. 's, through material substitution in a host of traditional base metal applications and generally reduced world-wide economic activity. In addition to shrinking markets our collective environmental consciousness has raised effluent standards and workplace hygiene and the employee's as well as government's economic expectations of how much ought to be derived from ''nature's riches''.Industry has responded with technological changes which, it was hoped, would counteract the cost squeeze in which it found itself.I would like to briefly enumerate the major changes, as I see them, that have taken place in the main unit operations that form the normal processing chain for base metals.While the following paper will mention several brands of products, I would like to emphasize that these are the ones that I am most familiar with and is not to say that they are the only manufacturers which have contributed to changes. In fact it ls fair to say that all makers of mining and processing equipment have made improvements to their products, to a greater or lesser degree; they have had to, to still he in business in 1986."

Jan 1, 1987

By Gordon W. Parsons, Ross E. Sampson

"THIS PAPER will trace the work done in bringing the Munro underground ""A"" •Orebody into production to replace the open pit, which was scheduled to be completed early in 1959. Included will be an outline of the exploration work and early planning, and of the final decisions on mining methods. Some of the more detailed work will be described and reasons will be given for the decisions made regarding development work, mine ventilation, ground support, and equipment. Brief mention will be made of open pit operations, as these have had some influence on underground development. Also, some of the main geological features of the ore occurrence will be de-scri0bed, as these had to be taken into consideration when making decisions on ore development and mining methods.LOCATION AND HISTORYhe Munro mine of Canadian Johns-Manville is in Ontario, approximately 50 miles east of Timmins and 40 miles west of the Que-bec-Ontari-0 boundary. The producing orebody is in the southwestern part of Munro township. Property controlled by the Company extends nortl1westerly about 2¥2 miles into Beatty township, on which two other interesting asbestos-bearing zones have been partially expl-0red. Active exploration work on the property was started in March, 194.9, and continued until the summer of 1950."

Jan 1, 1960

By W. W. Bake

INTRODUCTION IN IN JUNE, 1943, the main pillars of the Beattie Mine glory hole failed, allowing over a million yards of wet clay and debris to flow into the mine, completely filling all workings to within seventy feet of the 3rd level. The resulting Job of clearing these workings and rehabilitating the mine represents a unique and hazardous operation, seldom, if ever, previously encountered in Canadian mining. The purpose of this paper is to describe one phase of this operation -that of cleaning and rehabilitating the mine from the 6th to the 9th level -to outline briefly the events which led up to this work and to describe the techniques and costs involved. It will be noted that such costs, methods, and performance figures as are dealt with in this paper refer only to work in the internal shaft and adjoining workings from the 6th to the 9th level, previous work having been done under other supervision and management. The Beattie mine is in Duparquet township, northwestern Quebec, twenty miles northwest of the town of Noranda and twenty-three miles southeast of the town of La Sarre. The mine and the town of Duparquet, which it?supports, are accessible by highway from Noranda throughout the year. Production at the Beattie mine began in May, 1933, and up to June, 1943, twenty-one million dollars in gold and silver had been recovered from five and a half million tons of ore.

Jan 1, 1951