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By H. Warren Newcomen, Dennis C. Martin

"This paper describes the investigation of a large, progressive slope failure on the southeast wall of the east pit at Highmont Mine, British Columbia Geotechnical investigation s consisted of geological and structural mapping, assessment of blasthole drilling records, review of rock core information, slope movement monitoring and back analysis of various possible failure modes. Climate records and mining history were also assessed to determine their relationship to slope movement .Analysis of movement monitoring records and geotechnical information indicates that the failure is deep seated. The upper portion of the failure surf ace occurs along clay filled discontinuities. The lower portion of the failure surf ace appears to occur through the highly altered rock mass. High groundwater pressures and mining at the toe of the slope are documented to have had a major influence on stability at various times during the failure. Stability analyses results are presented and possible remedial measures are discussed.IntroductionHighmont Mine is located near Logan Lake in the Highland Valley approximately 50 km southwest of Karnloops, British Columbia (Fig. I). Mining of the porphyry copper and molydenum ore bodies began in 1980. In May, 1983, when mining in the east pit had progressed to a depth of about 60 m (200 feet) , a failure (designated the Southeast Failure) began to develop in the southeast corner of the east pit. Subsequent mining to a depth of 110m (360 feet) was accompanied by frequent and substantial slope movements involving between 500000 and I 000 000 m3 of rock . The slope was monitored extensively to assess short-term movement trends for operational safety. Geological mapping, core logging and rock mechanics testing were used in conjunction with the long-term monitoring information to determine the failure mechanism, conduct stability analyses, assess the effects of instability on pit design and enable design and installation of remedial measures."

Jan 1, 1988

By Lionel Roberge, Borge J. G. Fredriksson

"Late in 1981, a six-rope friction hoist was installed in the Number 2 shaft at Les Mines Seleine Inc. on the Madeleine Islands in Quebec. This paper deals with the reasoning behind the selection of hoisting equipment from the economical point of view, safety point of view, future needs point of view, etc.After establishing the basic parameters for the hoisting system, features of the most common types of hoists (i.e. single-drum hoist, double-drum hoist, Koepe hoist) are briefly laid out. The reasons for selecting a friction (Koepe) hoist are summarized. However, why go for a six-rope hoist rather than the (in North America) more common four-rope hoist? As the subject hoist is the first six-rope hoist in Canada, this question is studied in more detail, covering initial cost, maintenance cost, etc., as well as practical aspects, such as safety, physical dimensions, etc.In summary, experiences from other multi-rope hoist installations world-wide are presented.BackgroundIn 1980, Seleine Mines Inc. was established as a subsidiary of SOQUEM. The new mining company was to develop and operate a salt mine and associated harbour on the Madeleine Islands in the Gulf of St. Lawrence. The Madeleine Islands form part of the Province of Quebec. The mine has a planned annual output of 1.2 million metric tonnes of salt, with reserves in sight for over 20 years. Mining will be by room and pillar, with an underground primary crusher and treatment plant. From the underground treatment plant, the salt will be transferred via conveyors to a 5.5-metre-diameter circular shaft and hoisted to the surface. Surface transportation to the warehouse will again be via conveyor, and a conveyor will also transport the salt from the warehouse to the point of shiploading."

Jan 1, 1983

By H. Warren Newcomen, Dennis C. Martin

"This paper describes the investigation of a large, progressive slope failure on the southeast wall of the east pit at Highmont Mine, British Columbia Geotechnical investigation s consisted of geological and structural mapping, assessment of blasthole drilling records, review of rock core information, slope movement monitoring and back analysis of various possible failure modes. Climate records and mining history were also assessed to determine their relationship to slope movement.Analysis of movement monitoring records and geotechnical information indicates that the failure is deep seated. The upper portion of the failure surf ace occurs along clay filled discontinuities. The lower portion of the failure surf ace appears to occur through the highly altered rock mass. High groundwater pressures and mining at the toe of the slope are documented to have had a major influence on stability at various times during the failure. Stability analyses results are presented and possible remedial measures are discussed.IntroductionHighmont Mine is located near Logan Lake in the Highland Valley approximately 50 km southwest of Karnloops, British Columbia (Fig. I). Mining of the porphyry copper and molydenum ore bodies began in 1980. In May, 1983, when mining in the east pit had progressed to a depth of about 60 m (200 feet) , a failure (designated the Southeast Failure) began to develop in the southeast corner of the east pit. Subsequent mining to a depth of 110m (360 feet) was accompanied by frequent and substantial slope movements involving between 500000 and I 000 000 m3 of rock . The slope was monitored extensively to assess short-term movement trends for operational safety. Geological mapping, core logging and rock mechanics testing were used in conjunction with the long-term monitoring information to determine the failure mechanism, conduct stability analyses, assess the effects of instability on pit design and enable design and installation of remedial measures."

Jan 1, 1988

By J. Bigu, M. G. Grenier

"Dust size distribution and aerosol size distribution measurements have been carried out in several Canadian underground uranium mines. In addition, dust samples have been analyzed for long-lived radioactive products of the U-238 and Th-232 natural decay chains using ex-spectroscopy and -y-spectroscopy techniques.From the data collected one may summarize: (a) most airborne particulates are of size below I u-m and 50% by mass are found above 1 u-m; (b) dust clouds are bimodal; (c) preferential deposition of radon (thoron) daughters takes place on airborne particulates in the sub -micron range at about 0.1 u-m; (d) deposition of radon (thoron) daughters is proportional to particle surface area; and (e) ex-spectroscopy and -y-spectroscopy of dust samples reveals the presence of U-238, Ra-226 and some of their short-lived and long-lived decay products.IntroductionExtended inhalation of airborne radioisotopes poses a potential health problem to occupational workers. Because of this, monitoring of radiation and dust levels for dose exposure calculation purposes is not only recommended but in most cases mandatory.CANMET (Energy, Mines a nd Resources Canada) has long since been engaged in a comprehensive monitoring program aimed at determining dust concentrations in the respirable size range, aerosol concentration in the sub-micron range, and in the radioactivity associated with these particulates in underground uranium mines. Measurements have been carried-out with gravimetric dust samplers, dust size selectors (including a horizontal elutriator , a fineparticle spectrometer and Nuclepore* filters of different pore sizes) and a condensation nucleus counter(1 – 6). Inactive and active working sites have been monitored according to some typical mining operations. A summary of these data has been given elsewhere(3- 5)."

Jan 1, 1984

By James L. Parks, David M. Kjos

"Significant increases in mill liner life and plant availability can be achieved by following guidelines that have evolved from over twenty years of practical experience with autogenous grinding (A0) and semi-autogenous grinding (SA0) mills. A0 and SA0 mill liner functions, performance criteria, designs, wear-resistant materials and maintenance procedures are reviewed. Operating practices that can lead to accelerated wear and breakage are discussed.IntroductionEfforts to improve the performance of liners for autogenous grinding (AG) and semi-autogenous grinding (SAG) mills began as soon as the modern, large-diameter versions of these comminution machines were first intalled in commercial plants twenty years ago . While concentrators with conventional circuits were typically running at 95010 or better mill availability, many of the new autogenous and semi-autogenous circuits were struggling to achieve 80% availability. Liner maintenance, which involves not only material and labour costs but also loss of production, was quickly identified as one of the major reasons for downtime.Today, liner designs and materials have evolved to the point where virtually maintenance-free liner life of two to three years is possible in autogenous mills and one year in the more severe operating conditions encountered in semi-autogenous mills. Of concern, however, is that hard-won lessons from the past sometimes seem to be forgotten or ignored during the design of new mills and the operation of existing mills. As liner suppliers, we are often confronted with performance problems that could have been avoided by applying well-publicized guidelines for liner design and materials selection.This paper provides an overview of AG and SAG mill liner functions, criteria for evaluating performance, designs, wear-resistant materials and maintenance procedures. Also, operating conditions that can lead to accelerated wear and liner breakage are discussed in detail."

Jan 1, 1990

By J. R. Morris, A. E. Ball, G. W. Kuzyk

"AECL Research has constructed an underground laboratory for the research and development required for the Canadian Nuclear Fuel Waste Management Program. The experimental program in the laboratory will contribute to the assessment of the feasibility and safety of nuclear fuel waste disposal deep in stable plutonic rock.In 1988, AECL extended the shaft of the Underground Research Laboratory (URL) from the existing 255 m depth to a depth of 443 m in cooperation with the United States Department of Energy (USDOE). The project, which involved carrying out research activities while excavation and construction work was in progress, required careful planning. To accommodate the research programs, full-face blasting with a burn cut was used to advance the shaft. Existing facilities at the URL had to be modified to accommodate an expanded underground facility at a new depth. This paper discusses the design criteria, shaft-sinking methods and approaches used to accommodate the research work during this shaft extension project.IntroductionThe Underground Research Laboratory (URL), a major geotechnical research facility, has been developed by AECL Research, 120 km northeast of Winnipeg, Manitoba. The URL is part of the Canadian Nuclear Fuel Waste Management Program (CNFWMP), which is assessing the concept of nuclear fuel waste disposal in a vault deep in stable plutonic rock of the Canadian Shield (Hancox, 1986). The URL provides a representative environment to conduct a wide variety of geotechnical research relevant to nuclear waste disposal. Extensive characterization and monitoring programs were carried out prior to construction and will continue during operation. The operating phase experiments began in 1989 and will continue until the year 2CXXl (Simmons, 1990). Figure I shows the present extent of the URL facilities and the proposed future development."

Jan 1, 1991

By D. C. Carter, J. P. Anderle

"Exploration drilling of evaporite sequences in eastern Canada has undergone significant changes in equipment, techniques and philosophy since the early 1970s. The result has been the recovery of full-size cores from properly conditioned and stabilized holes, high quality open hole geophysical logs, and high quality metallurgical samples. The majority of modifications have resulted from the necessity to preserve the integrity of the evaporite deposit, and thus ensure the potential development, combined with the need for cost-effective high quality information. This is particularly evident in the priority placed on the development of non-erosive drilling fluids, casing and cementing procedures. The results are applicable to diamond drilling exploration of evaporite deposits anywhere in the world.IntroductionThe majority of current technical and scientific literature and expertise available on such subjects as drilling fluids or cementing procedures is applicable to large diameter, deep (several thousand metres) oil-field type drilling . The differences between oil-field drilling and wire-line core diamond-drilling are dramatic: large diameter, deep holes drilled with a low rpm tricone bit using large volumes of fluid pumped through a large annulus versus small diameter, shallow (less than 600 m) holes drilled with a high rpm diamond-set core bit using small volumes of fluid pumped through a small annulus. Exploration drilling of evaporite sequences in eastern Canada in the early I970s was conducted using oil-field equipment and techniques to complete holes of moderate (1000 m to 1500 m) depth . The prohibitive cost of these operations has necessitated that subsequent exploration drilling employs modified diamond-drilling equipment and techniques developed as part of a transition away from oilfield methodology. The result has been full size core, recovery approaching 1000/0 and the ability to run open hole geophysical logs; a combination of factors enhancing the collection of high quality information (Carter, I989a)."

Jan 1, 1990

By Sylvain Létourneau

Help organizations maximize the benefits of the data that they collect ? perform scientific research in: machine learning, data mining, statistics, artificial intelligence, soft computing, information retrieval, information systems, and natural language processing ? preferred application areas: Equipment Health Management, Bioinformatics, Health, Web Mining ? today?s talk limited to Equipment Health Management While the aircraft is still in the air, IDS: ? clusters relevant WRN, FLR, and snag (pilot) messages ? identifies probable causes based on TSM and provide links to corresponding TSM pages ? assesses MEL conditions (GO, NOGO, GOIF, ?) ? displays relevant maintenance history, suggests fixes based on similar cases ? Commercialization with MxI Technologies Ltd and Air Canada in 2000

May 1, 2008

In this paper, geostatistical techniques are applied to forecast the annual copper price in the short and medium terms (from one to five years ahead). These techniques allow the incorporation of monthly and multivariate information in the analysis and provide more accurate results than traditional approaches, especially as far as the one-year forecast is concerned. A second advantage of geostatistics stems from its ability to assess the uncertainty associated with the unknown future prices, thanks to estimation variances or confidence intervals, depending on the technique used. Such an assessment has a crucial importance in decision-making, from both macroeconomic and microeconomic points of view

Sep 1, 2004

By S. Caron, P. Radziszewski

Industrial practice in mineral processing shows that an important problem in understanding and monitoring in-mill parameters is due to the lack of fundamental knowledge and appropriate sensors. However, over the last decade, Discrete Element Method (DEM) modelling has shown an interesting potential in describing the fundamentals of grinding mill behaviour, in improving the understanding of internal grinding mill dynamics, and in developing solutions to industrial practice. With the objective of bringing this modelling technology into the concentrator control room to assist operators, this paper aims to describe the main elements needed to apply this emerging and developing technology to on-line mill performance monitoring.

Jan 1, 2004

By Richard C. Banting

Excessive vibration is known to have an adverse affect on soft body tissue and operators of heavy mining equipment can be exposed to vibration that exceeds levels recommended in international guidelines (ISO 2631-1, for example). Research has found that many of the seat and suspension systems currently used in mine haul trucks and load haul dump vehicles are actually amplifying the vibration. This overview presentation will outline the current research being conducted at Laurentian University and the University of Western Ontario, and the roles of partners in rating the ability of a number of commonly used mine vehicle seats to isolate harmful vibration.

Oct 1, 2010

By David L. Anderson

This paper explores the financial impact of the initial version of the Saskatchewan Potash Reserve Tax; first, a one; and second, in conjunction with the other taxes affecting the industry's profitability. A though the introduction of the Reserve Tax is shown to lead to a substantia increase in a hypothetical firm's effective tax burden, the more unusual outcomes frequently attributed to this levy on y occur after the imposition of other non-provincial tax rulings. Despite this qualification, the results obtained suggest that the Reserve Tax undoubted y acted as a catalyst in the polarization of attitudes during the ear y period of industry/government confrontation

Jan 1, 1979

By Knut F. Garshol

Quality and durability of sprayed concrete depends on the concrete mix design, the type and use of accelerator and all the aspects of the placement onto the rock surface in the underground working. A large number of influence factors are involved and they must be managed for a successful and durable permanent sprayed concrete structure to be produced. The paper discusses some of the central issues, including how to view the long-term effects of chemical admixtures and accelerators in wetmix sprayed concrete. Permanent lining sprayed concrete for rock support is increasingly being used today and the durability can be equally achieved as for any other concrete.

May 1, 2003

The Rabbit Lake In-Pit Tailings Management Facility contains frozen layers of tailings due to subaerial deposition during the coldest periods of winter. Thawing is required to ensure full consolidation of the tailings and to regain disposal space presently occupied by ice. Electric resistance heating has been used to heat soil for bitumen extraction and remediation of volatile contaminants. A preliminary evaluation of the application of electric resistance heating to thaw about 0.3 cubic metres of frozen tailings was conducted using tailings frozen at about -2 oC. Visible thawing of the tailings mass was observed after 25 hours, demonstrating the feasibility of this approach.

Aug 1, 2010

By M. J. Baker

Energy and Minerals Australia Ltd are undertaking a study of the recovery of uranium from the Mulga Rock Deposits in Western Australia. Approximately 80-90% of uranium identified to date is present as tabular layer up to 5 m thick within a lignite seam 30 m to 50 m below surface. Other metals are also present. Metallurgical studies at ANSTO Minerals laboratories in Sydney have focused on identifying a suitable uranium leaching process and assessing the possible downstream impacts of the organic material in the ore. The extraction of other metals has also been examined. This paper provides the results of testwork performed at ANSTO to date.

Aug 1, 2010

Commercial SOFC systems will likely utilize hydrocarbons or hydrogen produced from hydrocarbon fuels and therefore will likely be exposed to sulfur impurities. Conducting-Atomic Force Microscopy (C-AFM) is a scanning probe microscopy technique which maps both sample topography and conductivity with tens of nanometers resolution. In Ni-YSZ, C-AFM measures the resistance of the metallic network at scanned locations, with the ability to differentiate between interconnected and isolated metallic particles. We have applied C-AFM to Ni-YSZ SOFC anode materials, with the goal of monitoring changes in the conductivity of the Ni anode network resulting from SOFC degradation processes, such as H2S poisoning.

Jan 1, 2005

By David Meadows, Elmer Palmer, Steve Dixon

As part of the Goldcorp Inc growth plan Minera Peñasquito SA de CV has developed its polymetallic deposit with a large “state of the art” concentrator to process lead and zinc ores. The plant consists of two grinding lines including 38ft diameter SAG mills and 24ft diameter ball mills. During mid to late 2009 concentrator commissioning activities commenced. First concentrates were produced in October 2009 and now the plant is meeting its design basis of 65,000 mtpd per line. This paper describes the design and operational experience to date for its grinding circuit design, together with the recently commissioned HPGR crushing circuit.

Jan 1, 2012

By D. C. Van Aken, O. J. Rajtora

A research effort sponsored by the Department of Energy (DOE) and several steel producers, is investigating the benefits of coating steelcasting nozzles with various materials. Coatings were applied to casting simulation nozzles made from industrial tundish nozzles (primarily of magnesia) and industrial submerged entry nozzles (SEN's) (primarily of alumina-graphite) in order to extend casting time prior to nozzle clogging. Nozzles were coated by air plasma spray (APS) using a 9M series APS system from Sulzer-Metco. The ability of these coatings to provide protection from clogging was evaluated using a steel casting simulation. Substrate-coating compatibility was characterized using optical and SEM microscopy.

Jan 1, 2004

By J. Aguilar-Santillan, H. Balmori-Ramirez, R. C. Bradt, I. Vernet-Patiño, F. Cunha

Kyanite is an alumino-silicate mineral that has been widely used for the production of refractory products for industrial applications. Kyanite provides a high alumina content, it readily produces mullite during firing, good hot strength of products and can be adapted to produce dimensional stability of products during firing. This research addresses the application of kyanite in mixes to produce (0 dense mullite aggregates with the addition of alumina, (ii) dense composite refractory aggregates of forsterite / spinel with additions of magnesia, and (iii) dense cordierite aggregates with the addition of talc. Effects of attrition milling and conventional ceramic processing are addressed as they affect the properties of these unique aggregates.

Jan 1, 2004

By G. Tozsin

A six-stage sequential leaching procedure was used to assess the leachability of heavy metals from waste rock in Antamina Mine. Sequential extractions procedure is well established for fine and small (? 1g) samples. However procedures for coarse and large test samples are lacking. This study presents results of the sequential leaches tests conducted on relatively coarse and large representative samples in terms of the availability and mobility of metals. Selective chemical reagents were used to extract metals from six different fractions where metals released with each subsequent extraction are believed to be bound tighter than those released in prior steps and therefore less likely to be leached.

Aug 1, 2013