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By C. S. Gibson

INTRODUCTION I WELCOME the opportunity to speak on Programmes in Safety. The invitation to do so shows that those guiding affairs of the Institute in this District realize the practical importance of this subject. My remarks are intended primarily for mines having 100 to 400 employees, approximately. With minor modifications, however, they apply also to larger or smaller operations. Others, I hope, will derive benefit from this paper, for they, too, have a part to play in accident prevention; for example, contractors such as shaft-sinkers; manufacturers of equipment; and consultants and designers of mining, milling, and metallurgical methods. These troubled times stress, as never before, the importance of efficient operations in mining. The days are gone when neglect can be afforded. Safe working conditions and satisfied employees are essential for efficient production at reasonable cost. The mining industry of Ontario long has been keenly aware of the human aspects of this subject, and as a whole it has done much to decrease the frequency and severity of disabling accidents. The number of fatalities per 1,000 employees has been reduced from a high of 5 some two decades ago to an all-time low of 0.89 in 1948; the incidence was slightly higher in 1949, being 1.17 per 1,000. The reduction in non-fatal compensable accidents also has been outstanding, frequency having ?been reduced from over 200 per 1,000 employees some two decades ago to 54 per 1,000 at the producing mines in 1949. These statistics demonstrate progress. Nevertheless, the general picture still leaves much to be desired when viewed from two other angles.

Jan 1, 1951

By C. Dupuis, P. Waite, S. Leboeuf

Casthouses throughout the aluminium industry commonly use chlorine gas as a fluxing agent for furnace and in-line treatment of molten aluminium alloys. Its positive impact on the removal of alkali elements and non-metallic inclusions is well known. Nevertheless, the elimination of its use is highly desirable due to the safety and environmental risks associated with storage and handling. Over the past decade, the aluminium industry has significantly reduced its chlorine consumption. This has been achieved by maximizing the chlorine gas utilization efficiency during metal processing, and by the chlorine replacement for crucible and furnace metal treatment applications. Operation of sealed in-line treatment units without chlorine is now possible, but with lower or inconsistent removal efficiency penalties for alkali and inclusions respectively. This paper reviews the progress made at Arvida Research and Development Centre regarding the reduction of chlorine and the development of an alternative to chlorine for in-line metal treatment without penalizing the metallurgical performance.

Jan 1, 2006

By Raj K. Rajamani, Nikhil Dhawan

"Agglomeration has become common pre-treatment step to improve heap leach percolation thereby recovery, the fundamental understanding of the agglomeration process for crushed ores is still lacking. Agglomeration is required for ores which either contain excessive amounts of clay or an excessive quantity of fines generated during mining and crushing. Numerous experiments have been carried out in laboratory scale batch drums using different ores. It has been found out that experimental agglomerate size distributions exhibit self-preserving spectra. The self-preserving/ similarity distribution of the agglomerates is found to be independent of operating conditions and is uniquely determined by the size enlargement mechanism. An empirical model based on the absolute difference between moisture applied and optimum moisture was developed. This model uses self-preserving spectra in the form of a Rosin-Rammler distribution function to predict size distribution at different operating conditions. The empirical model was considerably easier to work with plant scale agglomeration drums. Also, a test known as dip test is developed which improves fundamental understanding of the agglomerate formation and growth mechanisms. This test also provides the progeny size distribution of each agglomerate size. The progeny size distribution was analyzed with a model that partitions the particles into a host and guest category. The ensuing partition coefficient identifies the behaviour of a particle as a host for other particles or a guest layering on other particles. This concept helps in identifying the type of agglomerate that would result for a specific feed size distribution. INTRODUCTIONHeap leaching is one of the hydrometallurgical processes that have served as a green and economically viable process for the treatment of low grade complex ores of copper, uranium, nickel, silver and gold (Dhawan et al., 2013). Heap leaching appears to be a favorable candidate for the least energy consuming process for low grade ores. In heap leach operations nowadays a pretreatment step known as crushed ore agglomeration has been implemented (Dhawan et al., 2013). A bed of agglomerates improves the uniform percolation of solution through the heaps of ore. Therefore, it was possible to treat wastes and mill tailings via agglomeration and heap leaching. Agglomeration pretreatment is required for ores which either contain excessive amounts of clay or an excessive quantity of fines generated during mining and crushing (Bouffard, 2005; Dhawan et al., 2013).While agglomeration has become common practice pretreatment step in heap leach operations, the fundamental understanding of the crushed ore agglomeration process is still lacking. The author reviewed publications up to 2012 on the crushed ore agglomeration process and did not come up with modeling studies on the topic (Dhawan et al., 2013). Some of the possible reasons can be the stochastic nature of the process, experimental difficulties, and lack of instrumentation for fundamental studies."

Jan 1, 2016

By B. S. Ignasiak, B. N. Nandi, D. S. Montgomery

The growing need to measure the extent of weathering of coking coal in storage and in transit prompted the comparison of the dilatation of coking coal on heating, which is known to be a sensitive index of oxidation, with the composition and volume of the gases produced by a mild pyrolysis of the same coal. It was found that the pyrolysis method had the advantage in that it could be used to study coking coals in advanced stages of oxidation, when the swelling properties had been largely destroyed. Of the various constituents in the pyrolysis gas, the most sensitive indication of coal oxidation was the volume of carbon monoxide evolved per gram of coal. For the coals examined, this index appeared to be at its best when the temperature of pyrolysis was approximately 35oC.

Jan 1, 1970

By John A. Hudson, Xia-Ting Feng, Joseph S. Y. Wang

Evolution over decades and progress over last five years have been made in many topics of interests to rock mechanics, geosciences, physics, and multi-disciplinary interactions in underground research laboratories and development facilities, as well as in underground energy recoveries and environmental assessments. Rock mechanics and geotechnical engineering advances are associated with quantifications of disturbed/damaged zones and rock alternation and bursting processes and creation of underground spaces and accesses associated with deepening of shafts and lengthening of tunnels. Geophysics and earth sciences advances are associated with continuing collections of seismic, electromagnetic, and gravitational data and conducting various thermal, hydrological, mechanical, chemical, and biological investigations, both separately, simultaneously, and in different coupled ways. Astroparticle and underground physics advances are associated with many long term experiments to detect rare events and needs for increasing larger and deeper halls to accommodate next generation detectors, shielings, and isolations. There are also increasing interesting in underground settings to explore multidisciplinary and inter-disciplinary sciences and technologies. Energy and environmental sciences and assessments have evolved from traditional oil and gas focuses to recent activities associated with green resources and alternative recovery/disposal strategies. The evolution and progress of these interdependent and related fields are discussed in this quadrennial Congress.

Jan 1, 2015

By R. S. Boorman, H. G. Ansell

"Poor separation of lead from a copper concentrate of a major base metal producer was thought to have resulted from copper (0.2-0.4%) in the galena which caused it to float with chalcopyrite. No inclusions of copper mineral were detected which could account for the flotation of galena. The tendency for copper-bearing galena to float with chalcopyrite was confirmed by Hallimond-tube experiments in which the floatability of copper-doped synthetic galena (0.1-0.4% Cu) was approximately four times as high as copper-free galena. The difference in the cell edge (5.9338 ± 0.0003 A, Cudoped galena; 5.9361 ± 0.0002 A, Cu-free galena) indicated that the copper was lattice-bound and did not occur as submicroscopic mineral inclusions."

Jan 1, 1973

By W. Petruk

"D. Doyle How large is the beam to which you referred? Are we considering Watts, Griffis the probe of a 1 micron sized particle?& McOuatReply Yes. The beam would be about 1 micron. We could enlarge or reduce it depending on the current in-put.D. Doyle Then chemically bound material we might not see. If you are restricted to 1 micron then you would not be able to separate things smaller than this. Is this not so?Reply We won't be able to analyse it but we will see it as the scanning electron microscope has a resolution down to about 0.1 microns. We should be able to get the general composition of such a grain plus its surrounding grains. We feel we can then make a reasonable estimate if it were as small as 0.1 microns. An accurate analysis would be achieved with grains of 3 and 4 microns.D. Doyle Would this have an application in the hydrocarbon field?Reply The lowest atomic number would be sodium. We wouldn't be able to go below that atomic number. Anything with sodiumor a larger atomic number would enable us to analyse the carbon.M. Fairwether Do you have any policy relating to priorities. For instance areCominco companies going to be limited in the amout of samples permitted to give everyone a chance because quite frankly our company, and I'm sure all base metals companies can hardly wait for the installation of this equipment. I can forsee two years back-log of work in the first month.Reply Quite frankly, I haven't looked at this. At the present time the work is under the START program but I suppose we will have to look at possible changes. Anything under the START program has first line priority.B. Thorndycraft Will the briquetting of samples be automated as well? Pinson MiningReply No, not at this point. Our polish section laboratory is first-class and can turn out 18 polish sections a day which is more thar we can handle.B. Thorndycraft With the capability of this machine to operate in a hands-off manner perhaps it could start to look for the 5 micron gold particle in tailings?Reply I have such a program using a wave-length spectrometer rather than the energy dispersive. The wave-length spectometer is about 10 times as sensitive and would scan the section much faster. A one inch diameter polished section would be scanned in about 7 hours for anything 1 micron or larger."

Jan 1, 1984

By J. E. Dutrizac

Mercury balances have been obtained for the flotation circuits at Pamour Porcupine Mines, Timmins, Ontario, and at Brunswick Mining and Smelting Corporation, Bathurst, New Brunswick. The mineral form of mercury in both deposits has been ascertained. At Pamour Porcupine, the mercury is approximately evenly divided among sphalerite, native silverelectrum and tetrahedrite-tennantite; at Brunswick Mining, this element is contained mostly in the sphalerite, although tetrahedrite (and possibly pyrite) also contains minor quantities.

Jan 1, 1979

By Thomas M. Barczak

A critical safety component for all underground mining is intrinsic and standing support systems. Specifically, tabular hardrock mining exploits a wide variety of deposits that require various methodologies to safely mine the ore material. Several new support systems have been developed in recent years for hard rock applications which have been modified or applied in a variety of ground control applications. These include prestressing devices, improved cribs, and free standing supports. Various standing support and prop-type systems have been designed for hard rock applications with seismic loading conditions to accept prestressing. The prestressing, using water-filled cells, creates an active load upon installation and is considered essential to maintain support during and after the blasting of the mine faces. Heavy seismic activity is also present in these mines and the prestressing units can provide some energy absorption capability to help preserve the integrity of the support. This paper presents an overview of these innovations in support technology.

May 1, 2007

Surfaces forces have been measured between gold sphere and gold-coated glass plate in xanthate solutions using an atomic force microscope (AFM). The measurements conducted in potassium amyl xanthate (PAX) and potassium ethyl xanthate (KEX) solutions showed long-range hydrophobic forces, with the force curves showing no evidence for nanonubbles on the surface. The strongest hydrophobic force was measured at contact angle of 94° with a decay length of 23 nm. The hydrophobic force became weaker at higher concentrations and after a long immersion time, which may be attributed to the xanthate species adsorbed on top of the first mono layer. The hydrophobic force became stronger when the residual xanthate solution is displaced by pure water, indicating that hydrophobic force becomes the strongest in pure water.

Jan 1, 2009

By Perry L. Christian

"Mana/ta Coal Ltd. 's Costello Mine, located seven kilometres east of Estevan, Saskatchewan, has been operating at the present location since 1960. During the past twenty-three years, annual production of lignite coal has averaged 590 000 tonnes. The coal is used for power generation and for industrial and domestic use. Markets, operating techniques, facilities in place and reclamation are discussed. Introduction The Costello Mine (formerly the Klimax Mine) is located in southeastern Saskatchewan, approximately 210 kilometres southeast of Regina and 5 kilometres from the United States' border, as shown in Figure 1. The present mine, 7 kilometres east of the city of Estevan, has been operating since 1960. The history, however, of the Costello Mine and of the Estevan Coalfield dates from the initial settling of the area in the 1880s. Mining initially consisted of burrowing into the side of the Souris River Valley or other hillsides where the coal seam was exposed. Eventually, slopes were put down in the Estevan/Bienfait area and vigorous underground activity existed. In the late 1920s surface strip mining was introduced. The use of strip mining progressed to the point where it completely replaced underground mining in the 1950s and it is the only method in use today. During the past 23 years annual production has averaged 590 000 tonnes. The lowest production was in 1960 when the mine was starting up at 167 000 tonnes and the highest production was in 1977 when production was 1 509 000 tonnes. The Costello Mine controls approximately 11 400 hectares of mineral rights in the Estevan area. This is made up of 4 900 hectares of freehold coal and 6 500 hectares of leases. The area forms a large, irregular shaped configuration. Most holdings are contiguous and adjacent. The mine also owns some 8 400 hectares of surface rights. The lands under the Costello Mine's surface rights control, which are not being used in the mining operation, are leased to local farmers and ranchers. This ensures that the land is used to its full potential, both before and after mining."

Jan 1, 1985

By G. Lodewijks

This paper explores the savings that can be achieved in the energy consumption of belt conveyors used in mines by changing the conveyor components, the operational parameters of the system or the belt properties. First the concept of energy savings is introduced by looking at the energy consumption of belt conveyors from a theoretical point of view. Also methods for the calculation of the power consumption of a belt conveyor and the associated emissions are presented. Two case studies are presented in which the effects of the change of the operational parameters of the system, in this case the belt speed, and the belt properties, in this case the application of aramid products in the belt, are presented.

Aug 1, 2013

By Will Callupe Arzapalo

The success of the minimization of blast induced-damage at Barrick?s Pierina Mine in Peru is the result of an effective working relationship between Mine Operations and the Geotechnical Services Department. A detailed design criteria manual is used to match the blast plan to the site?s varying rock types and slope designs. The Geotechnical Services Department has further developed a comprehensive pre- and post-blast checklist that is critical to the drilling and blasting process as it pertains to wall stability. Wall control blasts are evaluated with quality assurance field checks, vibration monitoring and frequency control, video assisted performance quantification and post excavation face profiling. These detailed observations are compiled and summarized in a blast performance evaluation that is considered to be an ?Industry Best Practice?. The information and detail provided by each performance summary allows accurate blast analysis and effective design refinement.

May 1, 2006

By S. E. Daniel

"Due diligence reviews are an essential part of mineral property acquisitions. One of the primary reasons to complete an environmental review prior to exploration property acquisition is to assess the potential environmental liability. It is critical to identify the potential reclamation costs or existing environmental liability associated with the exploration property. A review of the existing condition of the property and its history can allow prioritization of exploration targets and ease future expenditures for historic damages. IntroductionIn Canada and some other jurisdictions, the purchaser of a property is assumed to know, and is (in the absence of deceit or fraud) financially responsible for, what is purchased. A plea of ignorance, at least from the perspective of environmental liability, is not an acceptable excuse to avoid responsibility (Nelson, 1994). Therefore, if an exploration company (for the purposes of this paper, any organization conducting exploration work) purchases a property that has environmental contamination, the new owner is liable for the cost to reclaim the site to an acceptable level. The cost to reclaim the site is the environmental liability. The new owner is responsible for existing environmental liability of the property, even if the exploration company’s personnel were not aware of the problem. In simplest terms, buyers beware. Therefore, in order to protect the exploration company’s interests, the exploration manager should determine the characteristics of the property of interest prior to purchase or other involvement, and exercise due diligence.The term “due diligence” is often used in the mining industry. To ensure clarity, in this paper’s context, the author has chosen to use the following meaning: “… due diligence is used to describe a detailed data review, generally in connection with the purchase or sale of a mineral property, the approval of a large capital expenditure, or the borrowing of a large sum of money” (Smith, 1997).Directors of the exploration company are held liable for the decisions made, unless they have relied in good faith on,“…a written report of the auditor, or a report of a lawyer, accountant, engineer, appraiser, or other person whose profession lends credibility to a statement made by any such person” (OBCA, 1994)."

Jan 1, 2003

By R. P. Kofluk

The nickel-cobalt sulphides produced from limonitic laterite ores by Moa Nickel S.A. in Cuba are refined at the Corefco nickel-cobalt refinery in Canada. Significant economic implications are associated with the refining of precipitated sulphides containing elevated iron contents. The Moa Nickel S.A. operations encompass laterite mining, high pressure acid leaching (H PAL), and ultimately, precipitation of a mixed sulphide product. These processes are reviewed as they pertain to the control of iron and the formation of a mixed sulphide containing nominally 55% Ni, 5% Co and 1% Fe. The contributors to the iron content of the mixed sulphide product are reviewed; the major contributors are the HPAL operation and sulphide precipitation. The precipitation of iron during sulphide precipitation is influenced by the solution acidity, the iron and copper concentrations in the feed solution, and the presence of laterite leach solids. The significance of the copper concentration of the sulphide precipitation solutions is manifested by both physical and chemical modifications of the sulphide precipitates, presumably through the formation of fine copper sulfide seed particles.

Jan 1, 2006

By T. Mulja, Michel Boily, Anthony E. Williams-Jones, Pierre Pilote

"The Preissac-Lacorne batholith is composed of suites of early metaluminous calc-alkalic gabbroic to granodioritic intrusives, three late peraluminous monzogranite plutons and numerous Li, Be and Ta-bearing granitic pegmatites. The Lacorne pluton is dominated by biotite and biotite + muscovite monzogranites containing abundant Be and Ta-bearing granitic pegmatites (40-80% volume). The pluton is surrounded by swarms of unzoned or poorly zoned spodumene-rich pegmatite dykes. The La Motte pluton is composed of biotite monzogranites, biotite+ muscovite monzogranites and rare muscovite + garnet monzogranites. Li, Be and Ta-bearing pegmatites are less abundant than in the Lacorne pluton and are commonly associated with molybdenite bearing quartz-muscovite-K-feldspar veins. In the Preissac pluton, muscovite + garnet monzogranites and muscovite + biotite + garnet monzogranites are the dominant rock types. The pluton rarely contains granitic pegmatites and these are generally barren. However, numerous molybdenite bearing quartz and quartz-feldspar-muscovite hydrothermal veins are observed.Li, Be andTa-bearing pegmatites display a crude spatial zonation around their parent monzogranites. Spodumene-rich pegmatites are generally unzoned or poorly zoned and are confined to the surrounding metasedimentary or metavolcanic rocks or crop out in the early gabbroic to granodioritic intrusives surrounding the monzogranites. Ta and Be-bearing pegmatites are usually concentrated towards the margins of their parent monzogranites. The highly fractionated nature ofmonzogranites (high Rb/Sr, low K?Rb, Ba?Sr, Zr/Nb ... ), their peraluminous composition (corundum normative and muscovite bearing) and the numerous occurrences of Ta and Be-bearing pegmatite dykes represent important criteria for the exploration of fertile granites."

Jan 1, 1990

By Josée Dartois

En 1988, à l?instar de plusieurs états du monde industrialisé, le Québec décidait d?accélérer la cadence de l?assainissement des rejets industriels et lançait un programme intégré de réduction de la pollution industrielle visant, à la fois, les rejets dans le milieu aquatique, les émissions atmosphériques et les matières résiduelles. Ce programme fut intitulé le Programme de réduction des rejets industriels.

Nov 1, 2002

By W. R. Lindsay

Considerable attention has of late been given to the blasting of large amounts of ore in one operation, on account of the saving in labour and explosives and consequent low cost per ton, and also on account of the additional safety to employees. The blast here described, at the Hidden Creek mine. at Anyox, B.C., is not necessarily unique either in size or methods employed, but some interesting p10blems were encountered and the solutions of these may be of interest to others engaged in similar work. The ore consisted mainly of old scope-bottoms and sill pillars, although there also were some braces and parts of vertical pillars included. Some of the stope-bottoms were overlain by caved waste, and one of the problems was to break them in such a manner that the maximum amount of ore could be recovered without serious dilution with waste. The ore blocks, designated as the 385 silt and the 7 A-103 blocks, were under preparation for blasting for over a year, as conditions permitted. This work consisted in drilling long machine drill holes, varying in length from 14 to 20 feet. These holes were drilled with the Numa detachable bit, made locally, starting at 2~-inch diameter and bottoming at 2 inches for the longest length. The long hole drilling was used in the thinner sections of the area. For the stronger, thicker portions, powder drifts (3 ft. by 4 ft. in section) were driven for the powder charges. Reference to the plan and sections (Figures 2 co 8 inclusive) show the relative location of these, as well as the long drilling. The amount of explosives used in the powder drift charges averaged 0.25 pounds per ton of estimated burden, varying from 0.2 to 0.3 pounds per ton.

Jan 1, 1934

By Robert A. Bosschart, Harold O. Seigel

"Most electromagnetic methods presently used in mining exploration are of the moving source type; i.e., the primary field source is moved simultaneously and in a fixed configuration with the receiver. Of the fixed-source methods, which employ a stationary primary field and a moving receiver, the Turam method is the most effective and has marked advantages over alternative electromagnetic methods. The results are little affected by topographic relief, and a high degree of resolution can be obtained because of the constant relation between source field and investigation area. Another inherent advantage of the Turam configuration is that it provides more favourable dimensional relations. Thus, the primary field attenuates at a much lower rate than in moving-source configurations and, secondly, the method is size sensitive; i.e., conductor size affects the strength of the response, which is not the case with moving-source methods. These factors result in a considerably better potential depth penetration."

Jan 1, 1966

By A. T. GRIFFIS, R. J. GRIFFIS

A large magnesite-talc body is locared in Delora Township, 11 km sourh-southeasr of Timmins, Onrario. The deposit occurs in part of an Archean greensrone belt dominated by volcanic and sedimenrary rocks and large bodies of ultramafic intrusions. The magnesite-talc zane is abour 1800 m long, has a maximum width of 300 m and has been drilled ro 120 m below surface. Chemical analyses of rhe main carbonate zane average 20 ro 28% soluble MgO (magnesia), 5 ro 6% rota/ iron oxide and less rhan 0.1 % CaO (lime). Mineralogically, the zane consists of approximately 54% magnesite, 28% rate, /5% quartz and 3% hematire. Perrographic srudies suggest that rhe various assemblages of magnesite, rate, quartz and serpentine were derived from a parenr serpenrinire (after dunire). An early carbonitization stage, which produced a high-magnesite, low-talc assemblage, preceded a farer decarbonitizarion stage, which formed rhe main magnesite-talc assemblage. Despite a favourably low calcium oxide content of rhe magnesite-talc rock, considerable iron in the magnesire /at rice has limited the quality of the beneficiared product: rhe besr flotation concentrate to dare yields 92 to 94% dead-burned MgO. Experimen- I L t r i i c:~:.•-4- -------- ? -_;> ,•----1---- ta/ work continues on finding a process whereby high-purity magnesia can be produced on a commercial scale.

Jan 1, 1984