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By Philippe Angers

This article analyzes the social acceptability process of a mining project located in an existing city. It will explore how the principles of sustainable development have been integrated in the project of the Canadian Malartic open pit mine held by the Osisko Mining Corporation, and the corporate social responsibility (CSR) initiatives proposed to strengthen the social acceptability of the project. This mine is located on the ancient south quarter of Malartic and has required the displacement of hundred of houses and five institutions. The location and the inherent social impacts generated by the relocation of the citizens of the south quarter makes this case particularly interesting to understand social dynamics in an era of environmental consciousness. These major constraints of the mine generate high expectations within the urban population with regard to the social and economic benefits it will receive from the project. In a context where society demands higher CSR from the corporation, Osisko is closely followed regarding their actions toward the sustainable development principles to see if they respect the environment and the desires of the community. From the beginning, the company had to be a model of sustainable development in various aspects reflected by the manifold interest of the population. To understand the endeavor made by the company to fulfill the demand of CSR, we will analyze how the company understood sustainable development principles and what CSR initiatives Osisko company put forward. We will explore the involvement of the company in various social aspects like employment, employee satisfaction, and the level of commitment to non-discrimination policy in employment, notably with the native populations. We will also take a closer look at the relationship built by the company with the community and the level of commitment with the various stakeholders of the community. In this way, we will be able to seize the level of involvement of the company in the fulfillment of the principles of sustainable development toward a higher CSR, and to specify the trajectory adopted to build social acceptance.

Aug 1, 2013

By D Veneziano, J Van Dyck, R Snow, W Pytel, O Zanoli

Best practice standards generally recommend assessment of the environmental and societal risks posed by tailings storage facilities, but they rarely specify how the analysis should be made. As a case study, this paper describes a safety assessment of the Zelazny Most tailings pond operated by the Hydrotechnical Unit of KGHM Polska Miedz SA in Poland. The complete assessment includes a failure mode effect criticality analysis (FMECA) that considers all conceivable failure modes, but this paper focuses on one key mode, the loss of stability during the planned raising of the crest above its current level. Reliability against static dam failure considers uncertainty on the safety factor in a limit equilibrium approach. The threat of dynamic (earthquake induced) instability is assessed by developing a model of future seismicity as a function of the mining plan and considering uncertainty on the induced permanent displacements along critical sliding surfaces. We quantify the additional level of protection against outflow provided by the beach using an event tree with expert-assigned probabilities. Continuous monitoring of the dam for premonitory signs of instability and a set of loss-prevention plans in the case of a spill provide additional layers of protection; their effectiveness is quantified by estimating the fraction of the population that could be evacuated as a function of warning time. The probabilistic analysis indicates that the safety targets are met and produces practical recommendations on how to maintain and improve the safety level while the dam crest is raised above its current level.CITATION:Van Dyck, J, Pytel, W, Veneziano, D, Snow, R and Zanoli, O, 2015. Safety of a tailings storage facility against dam instability, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 253–262 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By W. D. Haley

The report of the Forestry Committee, presented to the recent Imperial Conference at London, is discouraging in its view of the future of timber resources and supplies. From a review of the forestry situation throughout the world, there is every likelihood that, thirty years from this, a shortage of the soft-woods will be severely felt. In the United States, only about one-third of the present forest area contains virgin timber. This will be cleared at the rate of five and a half million acres a year, so that in twenty-five years it will be about all gone. Canada has only about 27 per cent of her original forests left, and her virgin soft-wood will last but another half century. At the present time, the value of her lumber products is over $300,000,000 annually. During the summers of 1909 and 1910, the Government of Nova Scotia caused an examination to be made of the forest conditions in this Province. The reconnaissance, which was under the direction of Professor B. E. Fernow, of Toronto, involved an examination of the various soils, the rate of growth of the wood, and a general survey of the forest area. The importance to the Province of conserving its forest resources was clearly shown, and a number of recommendations were made, which; however, were never acted upon.

Jan 1, 1927

By Joe H. Skidmore

This paper, describing mining and milling methods and costs at the Gold Hill mine, is one of a series being published by the Bureau of Mines. Boise Basin, in which the geld Hill mine is located, is in the central part of Boise County, Idaho, about 30 miles by air line northeast of Boise. The mine, owned and operated by Talache Mines, Inc., is at the southern end of the town of Quartzburg. About 115 to 125 tons daily is mind by square-setting and is treated in an amalgamation plant.

Jan 1, 1938

By The Staff

"THE Wabana iron ore mines, owned and operated by the Dominion Steel and Coal Corporation, Limited, .are on Bell Island in Conception bay, on the east coast of Newfoundland. Mining began on surface in 1895 and, although open-pit work is still done on a small scale, the entire output may be considered to•be derived from extensive submarine workings. In 1958 the average daily production of hematite ore was close to 12,000 tons, almost all of which was concentrated in a heavy-media plant. SUMMARYThe character, occurrence, and extent of the submarine bedded deposits enabled early operators to meet prevailing market demands with the minimum attention paid to exploration. Mechanization of the mine and the pressure for sustained high tonnages since 1955 have emphasized the importance of an expanded exploration and development programme.A serious handicap has been the impossibility of utilizing normal diamond drilling methods to explore ore conditions in advance of mining faces. Drilling between tl1e bedded zones has been done but the major difficulty has been to delineate ore reserves in the lower bed, which has the greatest ore potential of the three mineable seams."

Jan 1, 1960

By B. W. Gandrud, G. D. Coe

"INTRODUCTION The Southern Experiment Station of the U.S. Bureau of Mines, cooperating with the University of Alabama and Alabama coal producers, has made a series of investigations of the washability of coal from commercially important bens of Alabama. The results of 13 investigations pertaining to the Mary Lee, Clark, Black Creek, Jefferson, Pratt, Corona, Carter Brookwood, Blue Creek, Thompson, and Woodstock beds have been published. 4/ This report, the fourteenth of the series, deals with run-of-mine coal from the Henry Ellen bed at the Acmar No. 5 mine of the Alabama Fuel & Iron Co.The Acmar mine is 1/2 mile west of Acmar, Saint Clair County, in the northern part of the Cahaba field. Present production at the mine is about 800 tons per day, all of which, accept the lump coal, is treated in jigs. The washability data were obtained by means of screen-sizing and float-and-sink tests. There are included, also, tests showing the extent of liberation of impurities by recrushing the coarser sizes of coal from the top bench and tests showing the flakiness in selected sizes.SAMPLING AT THE MINEThe Henry Ellen bed at Acmar consists of two benches separated by a shale parting. At the point of sampling the top bench was 6 feet 3 inches thick and contained a 1-inch and a 1 1/2-inch band of bone. The bottom bench was 5 feet thick and was separated from the top bench by 20 inches of shale. In taking the samples for the washability study the working face was squared up, and a representative 2-ton section was out from each bench. The shale parting was discarded, according to usual mining practice."

Nov 1, 1936

By T. Negeri

Flotation is the most efficient and preferred solid-solid separation method in mineral processing. However, enhanced production of high-grade concentrates at sufficiently high recovery still poses technological challenges to-day. A novel flotation method to produce final-grade concentrates from finely-ground ores in a single step is being developed and tested by CANMET. For the complex sulphide ores tested, grades are superior while recovery is considerably improved. Furthermore, concentrate production rates, at similar recoveries, are faster than for the conventional rougher-scavenger-cleaner configuration. This paper discusses the physical operating parameters affecting Cu-Zn flotation metallurgy.

Jan 1, 1995

By Byron M. Bird, Earl R. McMillan

"The method and apparatus described herein was developed at the Northwest experiment station of the Bureau of Mines, Interior Department, in cooperative research work with the University of Washington. A fuller description will appear in a bulletin entitled ""study of coal washing problems in the Pacific Northwest, to be published by the University. During the past four years this Bureau and the University have been co-operating with various coal companies in the Pacific Northwest in an extensive study of coal washing problems. Much of the valuable data resulting from this study has been obtained with the well-known float-and-sink test. This test has known for a number of years****, but its possibilities have not been thoroughly understood. A few investigations have developed apparatus and technique suitable to their needs, but these were not adopted to the conditions faced in the Northwest. Thus, the necessity arose for designing suitably equipment and working out a method of procedure or technique in carrying on the fundamental studies of coal washing by means of the float-and-sink test method."

Feb 1, 1924

By V. “Ram” Ramachandran

"In view of the increasing number of environmental regulations that have been promulgated all over the world in the last thirty years, non-ferrous smelters and refineries have had to learn and adapt to treating process bleed waste streams containing heavy metals. The result of such treatment invariably yields a gypsum-saturated solution containing salts such as alkali metal sulfates, chlorides and fluorides. Presence of anions such as sulfates, chlorides and fluorides in the discharge streams – presently not a major problem- are coming under increasing scrutiny and will have to be addressed in the near future. It is envisaged that discharge limits for sulfate ions will be in place in the near future. Treatment of brackish water to produce drinking water also results in brine streams containing alkali salts that have to be addressed for proper disposal. This paper reviews treatment options for such streams containing high levels of total dissolved solids with emphasis on sulfate removal. Areas covered would be: a) chemical treatment for removal of various constituents that make up the total dissolved solids b) processes for sulfate removal processes –thermal and non-thermal-to recover and reuse of treated water and c) brine use and treatment options.INTRODUCTIONThe rising cost of water and meeting the ever-changing stringent environmental discharge regulations make water recycling and reuse essential. The metallurgical industry has used water as a medium for dissolving and/or rejecting metals and chemicals in addition to removing thermal energy. Any excess process effluent is collected and sent to end-of-pipeline treatment and ultimately discharged to surface water for disposal under a permit. The conventional- and probably the cheapest way -of treating metal-bearing process effluent streams is lime neutralization followed by sulfide polishing for elimination of heavy metals to produce a stream that meets NPDES discharge limits. This results in a stream containing dissolved solids.These dissolved solids normally comprises of inorganic salts. The possible constituents are cations calcium, magnesium, sodium and potassium. The anions are sulfate, chloride, fluoride, nitrate, carbonate and bicarbonate. In addition to these constituents, the treated effluent streams contain very small amounts of heavy metals, oxyanions such as arsenites, arsenates, selenites and selenates. Process streams from gold operations contain residual cyanide. Small amounts of ammonium ions are also present in these streams based on the pH of the solution."

Jan 1, 2012

By Paul E. Queneau

The QS (Queneau-Schuhmann) copper converter is a gently sloped, stepped, horizontal kiln-type tilting reactor in which desired bath oxygen activity, compositional and temperature gradients are created by countercurrent flow of matte and slag phases through a series of controlled bubble plume, mixer-settler configurations. Flow of gas and slag is normally concurrent. Copper sulfide concentrates are top-fed, employing oxygen flash burners. Oxygen and oxygen-carbonaceous fuel mixtures are bottom-blown into the smelting bath through judiciously located, independently regulated submerged injectors. Composition and mass flow rates of injector inputs are controlled to produce bubble plumes of desired character, without jetting through and out of the bath. The mixer-settler pattern can be reinforced if desired by employment of suspended shallow baffles. State-of-the-art instrumentation provides timely information required to govern key process variables. The outstanding capabilities of the QS converter for coppermaking have now been indicated by the current success of industrial QSL (Queneau-Schuhmann-Lurgi) leadmaking reactors. Modified converter designs are employed for leadmaking, nickelmaking and steelmaking.

Jan 1, 1993

By Thomas Brunsing

The program was carried out to develop deep kerfing and core breaking techniques to be incorporated into the design of a field prototype hard rock mining machine. The field machine is designed to mine non-abrasive bedded deposits up to 20,000 psi in uniaxial compressive strength. The mining technique involves cutting approximately 2 ft deep parallel kerfs spaced 2 ft apart in either a horizontal or vertical direction and subsequently breaking out the cores so defined. The prototype machine is intended for demonstration of the technique in a quarry or equivalent field environment. The program was aimed at minimizing the required kerf width, obtaining reliable breaking within that kerf width and determining cutter blade requirements necessary to achieve a mining rate of 20 ft3/min. Full scale breaking experiments and 1/2 scale kerfing experiments were employed to evaluate the system. High strength concrete test specimens were used to simulate the rock being cut and broken. The test results indicate the kerf/break technique can achieve the desired mining rate by utilizing two 7 ft diam blades to cut 2 in. wide by 24 in. deep kerfs. A lateral load applied at the base of the kerf (base shear) was selected at the core breaking technique to be employed by the full-scale prototype machine.

Jan 1, 1983

By I. Iwasaki

In recent years the rapid depletion of high-grade iron ores and the demand by blast furnace operators for increasingly low-silica ores have stimulated interest in flotation studies of low-grade iron ores, such as wash-ore tailings and oxidized taconites. Four processes have been reported for the flotation separation of these iron ores--anionic and cationic collection of the iron oxides, cationic collection of siliceous gangue, and anionic collection of activated siliceous gangue (5).5/ The effectiveness of any one method, however, depends largely on the mineralogical composition and on the physical structure of the sample; hence, a comprehensive study of the floatability of the individual minerals occurring in these materials is essential. A review of the literature shows that the floatability of hematite and magnetite has been frequently investigated, whereas very little corresponding information is available for goethite, or for its more earthy form, limonite, both of which are abundant in the Mesabi and Cuyuna ores (19). The purpose of this investigation was to formulate general information on the floatability of goethite. Vacuum flotation, contact angle measurement, and simplified flotation tests using a modified Hallimond tube were used. The experimental results were correlated with the electrokinetic properties of goethite as determined by streaming potential measurement. The results were used to interpret the batch flotation tests made on an artificial mixture of quartz and goethite.

Jan 1, 1960

By R. S. Celmer

The distributions of cobalt, molybdenum, copper, and selenium between nickel matte and silica-saturated iron silicate slag have been determined in the region of the metallic saturation boundary, at 1523 K. Results are given as a function of the composition of the coexisting Fe-Ni alloy and the activity of iron in the system. Under strongly reducing conditions, these minor elements display a marked preferential accumulation in the sulphide phase. It is shown that the dissolution of cobalt and molybdenum in slag follows an oxidative mechanism, and distribution equilibria are correlated with the oxygen potential. From these data, the thermodynamic properties of cobalt in nickel matte are computed. Further, comparisons of minor element partitions are made between the nickel and copper matte smelting cases under metal saturation conditions.

Jan 1, 1988

This paper describes basic parameters, such as surface forces and film elasticity, affecting the stability of foams (two-phase froths). We used the thin film pressure balance (TFPB) technique to measure the surface forces in foam films stabilized with various frothers such as pentanol, octanol, methyl isobutyl carbinol (MIBC), and polypropylene glycol (PPG). The results were compared with the foam stabilities measured experimentally and the film elasticities calculated using a new model developed by Wang and Yoon (2006). It was found that at low electrolyte (NaCI) concentrations foam stability is controlled by both film elasticity and surface forces (or disjoining pressure), the relative contributions from each changing with frother type and concentration. Further, the kinetics of film thinning was studied at a high electrolyte concentration. The results obtained in the present work showed that the major role of a frother is to decrease the hydrophobic force rather than to increase the film elasticity. This conclusion is drawn from the observation that at the typical frother (MIBC) concentrations employed in flotation, frother additions cause sharp decreases in hydrophobic force while causing relatively little changes in film elasticity.

Jan 1, 2006

By Alan Rice

Abstract-The mechanism by which stratiform ore deposits of PGE (platinum-group elements) are laid down in ultramafic igneous complexes is not completely clear. Early studies by the author and coworkers on numerical analyses of the convective cooling of low-Rayleigh-number magma chambers examined the effect of suspended crystal load on fluid density, and raised the possibility that the growth of the suspended crystal load during cooling could split a magma chamber into several convecting layers. The lower layers would have a higher content of refractory phases than the upper layers, which would consist of more evolved melt. This paper considers numerical modelling, as well as theoretical and experimental work in other fields dealing with suspended loads in fluids. The calculations, which are based on the physics of convecting magmas, yield quantitative relationships consistent with the observation that economically interesting stratiform PGE deposits are restricted to large magma bodies, and also yield estimation of the depth in a magma chamber at which certain grades of mineralization may occur.

Jan 1, 1997

By G. A. Savanick

The Bureau of Mines has designed, fabricated, and field tested a water jet cutting device capable of perforating nonmetallic well casings for the purpose of completing or stimulating in situ uranium leaching wells. The device is lowered into the wellbore, where it issues a high-velocity water jet that penetrates either a polyvinyl chloride or fiberglass casing, cement, and from 1 to 4 feet into the surrounding uraniferous sandstone. The resulting perforations allow leaching solution to pass between the sandstone and the wellbore. This report describes the water jet perforator, tells how it is used, presents cost data, and discusses the results of laboratory and field tests. The tests were designed to (1) determine the optimum operating conditions for water jet perforation, (2) assess the effects of changes in these conditions, (3) evaluate the performance of the water jet perforator under actual conditions, and (4) compare this method with other methods of well completion. These tests showed that water jet perforation is superior to conventional well completion methods for selectively achieving communication between the well-bore and adjacent sand while maintaining sand control, for restoring permeability lost through wellbore damage, for stimulating poorly performing wells for completing wells with casings that have inside diameters as small as 2 inches, and for extending the effective well diameter.

Jan 1, 1981

By A. D. Fisher

This paper describes the future position of metallurgical coal, particularly as applied to Canadian reserves. Quality coking coal is declining in availability, but preheating practices may alleviate this situation to some extent. Two new processes are discussed in the paper - formed coke and direct reduction - and their coal specifications are outlined.

Jan 1, 1972

By Marco V. Ginatta

Current world production, 60'000 ton/y, is exceedingly too small for titanium's extraordinary combination of favorable properties; it should be 1,000,000 ton/y (7% of stainless-steel). Prices that competitively sustain that sales volume are achievable only with electrolytic production, as it is for all other commercial nonferrous metals. But titanium does not have its commercial electrolytic plants yet, because of producers decisions and strategies, scientists works, industrial problems with chloride process, lack of consumers sponsors. Fluoride high temperature process has the advantages of aluminum electrolysis, plus other favorable characteristics specific to titanium and its feed material. One electrolytic titanium potroom replaces several different plants used for sponge production. Production of titanium ingots with zero defect is achieved. The solidified cathode rectangular slabs are suitable for direct rolling.

Jan 1, 2001

By John M. Devine

The severe corrosion of equipment that is caused by the presence of hydrogen sulphide in oil and gas has been described in detail by several authors. Such corrosion, termed "low-temperature hydrogen sulphide corrosion", presents a somewhat different problem from the "high-temperature hydrogen sulphide corrosion" that is encountered in refinery operation and which has been described by various-investigators of refinery corrosion.

Jan 1, 1932

By Jennifer Mager, G. P. Martins, Dean Mussatti

"The role of lead, at low concentrations in high pH cyanide-electrolytes, on the dissolution behavior of gold, has been a topic of scientific and industrial concern for well over a century. The recent paper by Kondos et al [1] at CANMET (1995) this continuing interest and apparent importance. Nevertheless, the mechanism(s) by which this (and other heavy metal) component influences the electrodics of this electrochemical system has still not been unequivocally demonstrated. Instead, several plausible hypotheses, by pioneering researchers in this field, have been advanced and reiterated OVer the ensuing years. While it is generally accepted, based on equilibrium elctrode-potential calculations, that reduction (or co-reduction when oxygen is present in the electrolyte) of lead on the gold surface may occur due to cementation (contact reduction), the cemented lead has never been characterized. The work presented has reexamined the role of lead in this system, by delineating the species distribution of these system components and by interpreting the results of potentiodynamic studies in conjunction with SEM analyses of a gold electrode.1. INTRODUCTIONThe leaching of gold ores in cyanide electrolytes has been practiced for well over a 100 years. Research conducted on this topic has been primarily focused on the effects of operating parameters such as concentrations of oxygen and cyanide, and the pH of the electrolyte; or the leaching behavior of carbonaceous and sulfitic gold-bearing materials.Mechanisms by which pure gold is leached in alkaline cyanide media, with oxygen serving as the oxidant, have been subjected to continual examination and re-examination in the published technical literature during this century. Recently, it has been speculated that without the presence in the electrolyte of trace heavy metals, such as lead or mercury, that gold would not be leachable. Researchers who have tackled this topic, have either considered heavy metals to be a natural occurrence in these systems and ignored the role they may serve in the leaching process, or they have deliberately focussed on controlling their concentrations in the system to undetectable limits. As a result, conflicting findings have been reported for what would appear - depending on the details provided in these reports - to be identical systems."

Jan 1, 1997