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By John F. Gartner

"Traditionally, the geologists of Canada have been occupied with the tasks of finding new mineral bodies, locating gas and oil fields or hunting for economic deposits of industrial minerals. A very minor percentage of graduate geologists have applied their skills to solution of the ""urban blight"" or employing their understanding of ""Nature"" for the optimum use of land by mankind. However, things are changing quickly. The role of the geologist in the planning process is being established. It is an exciting time! Geologists are now being consulted on a wide range of urban planning problems. These vary, tor example, from assessment of the geological environment for the new communities of Erin Mills and Meadowvale, which will have total populations in excess of 100,000 people (truly a satellite city), to a complete geological/ geohydrological assessment of the new sanitary landfill for the city of Guelph.Use of geologic techniques and methods for urban studies must be enhanced with certain skills not taught, in the past, to the geologist. These include airphoto interpretation, soil mechanics, geohydrology, municipal engineering and highway engineering to mention a few. The geologist has the unique training to assess the natural environment and to discover, warn and explain the implications of man's attempt to command his environment."

Jan 1, 1972

By J. R. Kish, J. Dabrowski

"The susceptibility to intergranular corrosion modes is a major technical issue preventing widespread utilization of higher strength welded AA7xxx extruded beam profiles, in the peak-aged T6 condition, in automotive bumper assemblies. A study was undertaken to evaluate the relative exfoliation corrosion resistance (ASTM G85-A2) as a function of joint design parameters, namely the base alloy composition, heat-treated condition and beam orientation after exposure to a cyclic acidified salt spray test. This paper documents the major findings extracted from this study.INTRODUCTIONBumper systems play a predominant role in the passive safety of an automobile, since they are one of the main structures for absorbing the collision energy in the event of an automobile crash. Heattreatable AA6xxx-series (Al-Mg-Si) and AA7xxx-series (Al-Zn-Mg) Al alloys, with relatively high strength, toughness, energy absorption, weldability and formability, make it possible to design costcompetitive bumper systems to crush in a controlled fashion. In this context, Cu-lean AA7xxx extrusions, such as AA7003 and AA7108, which exhibit higher strength than AA6xxx extrusion, such as AA6082, represent an attractive light weight material from which to fabricate bumper assemblies (Clausen et al., 2000; Pedersen et al., 2008; Chen et al., 2009).Arc welding is a key joining process for AA7xxx alloys within the transportation industry. A major technological issue preventing widespread utilization of arc-welded AA7xxx joints is the susceptibility to severe localized corrosion (Kent, 1970, Reboul et al., 1985; Holroyd et al., 1987). It generally occurs as exfoliation corrosion within a heat affected zone (HAZ) a few millimeters from the weld bead, or a type of stress corrosion cracking (weld-toe cracking), which initiates at the weld toe and propagates into the interfacial region between the weld bead and the HAZ (so called “white zone”). In addition to the micro-galvanic cell activity induced by the intermetallic compound constituent and strengthening particles present, there is strong evidence that macro-galvanic cell activity between the weld bead and base AA7xxx alloy may be playing a controlling role. Electrochemical profiles taken across fusion welded joints, in cross-section, during exposure to saline solutions suggest that a significant potential difference exists across the AA7xxx arc-welded joint (Shumaker et al., 1967; Grauer and Wiedmer, 1980; Tuck, 1985, Onoro and Ranninger, 1993). These studies consistently show that the HAZ and base alloy are more electronegative with respect to the weld bead (arc-welded with AA5xxx filler wire). Despite this initial important work, the majority of the recent corrosion research effort on welded AA7xxx alloys has focused on the performance of friction stir welds (Lumsden et al., 1999; Wadeson et al., 2006; Hatamleh et al., 2009)."

Jan 1, 2012

By C. J. Cattarello

"The Langmuir Mine is located seventeen miles south-east of South Porcupine in Langmuir Township.The property was developed as a Joint Venture between Noranda Mines Limited and the International Nickel Company of Canada with Noranda responsible for the operation of the property.The Mine came into production in June 1973 at a rate of 700 tons per day of nickel ore.MINING The mining method selected for the Langmuir Project was a sub-level retreat method. This consisted of driving sub-levels longitudinally in the ore body at 35 foot, intervals with the sub-levels being connected by a ramp from each main level for the use of trackless mining equipment.GENERAL GEOLOGY OF THE LANGMUIR MINE The deposit is situated about 1,000 feet west of the shore of Carmen Bay at the south of Nighthawk Lake in Langmuir Township. The area is underlain by andesite and rhyolite flows with iron formations which are intruded by gabbro, diorite, peridotite and late precambrian diabase dikes."

Jan 1, 1975

By A. M. Esteves

This paper offers an overview of local content policies and practice in the mining sector. Specifically, the paper aims to answer the question of how national and regional governments, industry and civil society can work together to seek an optimal outcome while pursuing their diverse objectives. The paper begins by defining local content and its scope at the subnational level. Specific recommendations for the design of local content policies to mitigate social, economic and governance risks are developed. The document then offers some recommendations regarding the role of partners in design, implementation, monitoring, and enforcement of local content policies.

Aug 1, 2013

By J. Clark

Erosion control during the mining cycle can be more effectively planned using Erosion and Sedimentation Control Plans (ESCPs). This raises the issue of who should develop an Erosion and Sedimentation Control Plan Guidance document (ESCPG) to standardize the content of ESCPs. A search for ESCPG documents in Canada revealed no examples for mine sites. In the U.S. there are a number of regulatory authorities who developed such documents for mine sites, including EPA. An ESCPG is expected to result in: (a) plans will be more standardized (b) more clarity and efficiency for those generating ESCPs; (c) assisting regulators tasked with reviewing/approving ESCPs; (d) providing guidance for the mine effluent permitting process relative to sediment control; (e) providing a basis for developing and including ESCPs in the Environmental Assessment (EA) phase and the mine economic assessment; (f) applying and optimizing ESCPs above the ?watersheds? of sediment ponds; (g) utilizing the ESCPG document for ?exploration? sites; (h) lowering the risk of adversely impacting water quality downstream of mining activities; (i) providing a methodology for determining the need for sedimentation pond(s) during the construction and production phases; and (j) providing a clear environmental sustainability message relative to sediment control if the mining industry takes the lead in developing an ESCPG. ESCPs will proactively create increased administrative (regulatory) efficiency in the EA and sub-EA reviews relative to erosion control and sediment release from mine sites. This also assists the new initiative in BC, One Project, One Process (OPOP) and synchronous permitting (a variation of concurrent permitting): as an example, enhanced erosion control planning at the EA phase then allows the synchronous permitting initiative to proceed efficiently, particularly for the mine permit (Ministry of Energy, Mines and Natural Gas) and effluent permit (Ministry of Environment). Approximately twenty more management plans (e.g. ARD/ML, explosive management, emergency response, hazardous waste, sediment pond operation, environmental effects, environmental sampling, etc.) may also be entered into the EA process to create increased efficiency, and then feed into the synchronous permitting effort. The BC OPOP initiative also adds support to the Canadian Federal ?One Project, One Review Process? approach. The ESCP and a sediment pond management plan will also address the Canadian Metal Mining Effluent Regulations requirement for all discharges from mine sites to meet a grab sample of 30 mg/L Total Suspended Solids.

Aug 1, 2013

By Doug Russell

Natsource: At a Glance l 160 employees l Global reach ? New York, Washington, Calgary, Ottawa, Toronto, London, Tokyo l Major Environmental Commodity Broker ? Rated as Top GHG Broker (Environmental Finance Magazine Survey, Dec. 2000 & 2001) ? Leading RECs Broker ? Large Broker of SO2, NOx l Large Energy Broker ? One of Highest Volume Gas Brokers ? Major Electricity Broker Overview l International Market l Implementing the Rate-Based Proposal l Assessment and Management of Risk from GHG Emissions Limitations

Nov 1, 2002

By V. Polotski

Initiated and financed by the Canadian Space Agency, Micro-Rover Platform with Tooling Arm (MRPTA) project has targeted the development of a robotic system with remote control and autonomous navigation capabilities for testing a large variety of analogous planetary missions. Although developed for planetary exploration, the navigation system is highly suitable to such areas of application as construction and in mining. Autonomous navigation system is capable of moving the platform to predefined position(s)/orientation(s) while continuously mapping the terrain, assessing its traversability and choosing most appropriate path to follow. Designed according to the JAUS (Joint Architecture for Unmanned Systems) framework, the system consists of several interconnected components. Following components are of particular importance: Pose Estimator (PE), Terrain Evaluator (TE), Map Manager (MP), and Path Planner (PP). The PE uses a minimal sensor configuration consisting of an azimuth gyroscope, inclinometer and wheel odometry. The PE provides reliable pose estimates in spite of pronounced slippage by employing extensive use of fused data. The TE uses a nodding laser scanner which continuously sweeps the area in front of the platform and constructs a ?traversability grid? (TG) of the surrounding area. Multiple TGs are constantly constructed along the platform motion path are combined into a terrain map maintained by the MP. The PP uses this map to compute a motion path Obtained path is executed by the motion controller and remains current until it is contradicted by the most recent map ? at which point it is re-planned. This paper addresses integration issues, lessons learned and also outlines the possible applications for construction and mining.

Aug 1, 2013

By C. Kim

The integration of three-dimensional (3D) data with infrared thermography has received much attention for its potential use as input data for building energy simulations. Therefore, researchers have proposed methods to integrate 3D data with infrared thermography obtained by different sensors. These studies show the potential of the integration of 3D data and infrared thermography using various systems. However, these studies have ignored property aspects of infrared thermography, such as the low resolution of infrared thermography and external environmental influences. Thus, their proposed methods to integrate 3D data and infrared thermography are inadequate because these problems can affect the resulting building energy simulation. This research proposes a framework that integrates infrared thermography and 3D data while accounting for the resolution and shadow effect of infrared thermography. The proposed framework consists of three steps. In the resolution enhancement step, bi-cubic interpolation is proposed. In thermal data correction from the shadow effect, the shadow area is detected from the visible image, and then the shadow effect is removed from the registered infrared thermography. Finally, enhanced infrared thermography is mapped to the 3D data obtained by a laser scanner. The performance of the proposed framework was evaluated using test images obtained from a building in operation. The experimental results show that the proposed framework provides a 3D thermal model that is useful and accurate in simulating building energy. It is expected that the 3D thermal model can be used for accurate energy simulation of existing buildings. In addition, the proposed framework can be applied in defect detection for buildings. Furthermore, this novel approach enhances infrared thermography using visible images.

Aug 1, 2013

By R. B. Anderson, N. J. Sherren

The mining equipment at the Scully Mine, Wabush, consists of approximately twenty-five large haulage units, eight large dozer-loader applications and seventy other related pieces of service and maintenance equipment. This equipment is operating in sub-Arctic conditions. This pa-per presents a description of the tire maintenance procedures in use here and discusses the tire troubles that are being encountered and the methods of dealing with them.

Jan 1, 1969

By M. J. MONEA

Canada's only economic high-swelling bentonite deposit is mined in Wilcox, Saskatchewan, by A vonlea Mineral Industries Limited. The bentonite resulted from devitrified and altered volcanic ash released during the Laramide Orogeny. Volcanic ash was deposited in a pre-Cretaceous basin that was formed by salt solution collapse structures. Sedimentary rocks in the Wilcox area belong to the Snakebite Member of the Upper Cretaceous Bearpaw Formation. Bentonite beds are 61 cm, 46 cm and 30 cm thick; these are separated by 365 cm and 182 cm of shale respectively. Saskatchewan bentonite is used primarily in the oil well industry.

Jan 1, 1984

By Maria Agostina Cinellu

Some aspects of the reactivity of the two different kinds of gold(III) oxo complexes [Au2(N,N)2(?-O)2][X]2 [N,N = 2,2'-bipyridine (bipy) (1), 6-alkyl-2,2'-bipyridine (bipyR) (2), R = Me a, CH2Me b, CHMe2 c, CMe3 d, CH2CMe3 e] and [Au2(C,N,N)2(?-O)][X]2 [HC,N,N = 6-benzyl-2,2'-bipyridine (bipyR') (3), R' = CHMeC6H5 a, CMe2C6H5 b] (X = BF4, PF6) have been studied. Treatment with water converts the unsubstituted bipyridine complex [Au2(bipy)2(?-O)2][PF6]2 (1) and the cyclometallated derivatives [Au2(C,N,N)2(?-O)][PF6]2 (3) into the water soluble monomeric hydroxo species [Au(bipy)(OH)2][PF6] (4) and [Au(C,N,N)(OH)][PF6] (5), respectively. These hydroxo species, likely the intermediates in the formation of the oxo complexes, are quantitatively reverted to the latter ones by reflux in anhydrous solvents. Both kinds of oxo complexes react with PPh3 to give OPPh3, the gold(I) complex [Au(PPh3)2][PF6] and the free bipyridine ligands. The reaction of the dioxo complexes [Au2(bipyR)2(?-O)2][PF6]2 (2a, 2b, 2c, 2e) with different alkenes gives the unprecedented alkene complexes [Au(bipyR)(?2-alkene)][PF6]. The styrene adduct [Au(bipyip)(?2- CH2=CHPh)][PF6] (7) (bipyip = 6-iso-propyl-2,2?-bipyridine c) has been characterized, inter alia, by X-ray diffraction analysis. Organic products arising from olefin oxidation are also found in the reaction mixture.

Oct 1, 2003

By Rafic Moubarac

FRP (Fiberglass Reinforced Polyester) equipment has been used in different and several applications during metals processing and extraction, and the hydrometallurgical process. Case histories of such equipment will be shown of major projects worldwide.

Jan 1, 2015

By J. Starkey

A comminution circuit in recent history, is one of the most difficult parts of a mineral processing plant to design with confidence. It is usually the most costly part of a plant to build, and it can consume up to half or more of the energy used on a mine site. To suggest that comminution energy usage is sustainable in the long term is not possible at this time. What we have to choose from today, based on more than 50 years of experience, does include the best available technology, and the best way to design it. There is controversy in the industry as to how to properly approach the subject of comminution design, with many of the optional solutions requiring a level of training and expertise beyond the ability of a non-specialist engineer. Semi-autogenous grinding technology in particular, has not been properly appreciated because of many recent mistakes in its application and design, which have blurred the positive perception about what SAG technology is, how it can be used, and how it needs to be designed and built. In order to change this, mine owners and senior managers need to take responsibility for, and learn to understand the fundamental challenges that a comminution circuit poses to the project, to the design process, to the operators who use the equipment, and to the resulting metallurgy. This address is intended to summarize these challenges and offer fundamental engineering solutions, which are clear, specific and in a format which is directly applicable to the mining and mineral engineering community.

Jan 1, 2018

By George W. Bain

The area in Quebec immediately north of the Ottawa river is underlain by a large area of granite gneiss intruded in lit-par-lit fashion into Grenville sediments and low silica intrusives of the Buckingham Series. This complex of metamorphic rocks is intruded by a much later magma found, chiefly, as a very large stock about 20 miles in diameter and extending from Brownsburg to Grenville, and as dykes and small outliers at various places adjacent to its outer margin. 1A similar stock at Rigaud, Quebec, is situated south of the Ottawa river and has been described by O. E. Le Roy. The earliest representatives of the later magma are a series of granodiorite dykes characterized by abundant hornblende, along with primary magnetite and subordinate sulphides scattered as roundish grains through anorthoclase and aligoclase feldspars and subordinate quartz. The rock is found as narrow dykes and shows no prominent secondary structures, either in the field or in thin sections under the microscope.

Jan 1, 1926

By C. W. Eggert

This paper gives an account of the E.V.O.P. tests made at the Copper Rand mill of the Patino Mining Corporation in Chibougamau, Quebec. The runs were made to acquire an understanding of the method. A description of events, along with conclusions, observations and opinions, is out-lined.

Jan 1, 1967

By O. Engler, J. Friis, S. J. Andersen, C. D. Marioara, Y. Aruga

"This work investigates the early stages of precipitation in Al-Mg-Si alloys using a combination of high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), selected area electron diffraction (SAED) and density functional theory (DFT) calculations. Quenching from a high temperature (solution) treatment leaves an alloy in a high-energy unstable state, with solute and vacancies in supersaturation. Thus, already at room temperature (RT) a large driving force exists for solute atoms to cluster and order on the Al matrix positions. DFT calculations indicate that strain alleviation is important at this stage. We observe larger regions of Mg-dominated L10 ordering together with a Si-dominated ordering of smaller clusters in a particular geometry connected to the Si-network found in all the precipitates. In addition, building blocks of the main hardening phase ?'', stabilized by vacancies, are observed at higher, typical pre-aging temperatures.INTRODUCTION Al-Mg-Si (6xxx) alloys are widely used in industry due to a combination of favorable properties such as strength, ductility, corrosion resistance and lightweight. They undergo a complex production route, usually consisting of the following thermo-mechanical steps: casting, homogenization, extrusion or rolling, solution heat treatment (SHT) and artificial aging (AA). The SHT takes place at temperatures above the solvus line in the phase diagram, usually between 500°C and 570°C, followed by a rapid cooling to RT. This ensures that high amounts of solute atoms, uniformly distributed on the cubic face-centered (FCC) Al lattice, together with a large amount of vacancies, are quenched-in. The material is therefore in a super-saturated and unstable state. During the subsequent AA, at temperatures usually between 150°C and 220°C, the solute atoms diffuse and cluster, forming metastable precipitates with needle/ lath/ rod morphologies having the main growth direction along <100>Al. With a maximum alloy solute level (Mg + Si) of only 2%, these precipitates increase material strength up to three times that of pure Al, and are essential for the final material properties. To understand and make better use of this phenomenon, it is imperative to research the nature of the precipitates (such as their atomic structure), measure their key parameters (number density, size, volume fraction) and connect it to material properties (Marioara, Andersen, Zandbergen & Holmestad, 2005; Marioara et al., 2014). The following precipitation sequence is given for the Al-Mg-Si system:"

Jan 1, 2018

By T. Guan, G. Fu, X. Zhou, L. Deng

"One kind of tailings from gravity separation of polymetallic mine contains 0.5–0.8% SnO2. The proportion of –0.037 mm size fraction of the tailings is 37.12%, and the distribution rate of SnO2 is 60.32% in it. For this tailings, two processing technology was carried out. One was felt-shaking table gravity separation in which the concentrate with a grade of 30% SnO2 at a recovery of 10% was obtained. Another was flotation-gravity separation in which the concentrate with a grade of 51.20% SnO2 at a recovery of 51.69% was obtained, but the dosage of collectors was as much as 990g/t. Therefore, the experimental research on the influence of grain size composition on the cassiterite recovery were conducted. The results show that: (1) the flotation recovery of the cassiterite distributed in +0.043 mm size fraction is only 10%, flotation recovery is not suitable for it; (2) a portion of cassiterite distributed in –0.01+0.005 mm size fraction could be recovered by flotation, but the tin flotation performance will be worsened rapidly and the dosage of collectors will be increased due to the increase of the content of –0.010 mm size fraction; (3) flotation processing is not suitable for –0.005 mm size fraction of the tailings. According to the results, a new technology has been carried out, that is discarding tailings by gravity separation-hydrocyclone desliming-flotation-gravity separation processing flow. The processing index is close to that of the flotation-gravity separation processing flow, and the collector dosage is decreased to 360 g/t by this processing technology. And, it has been achieved that the cassiterite slime is recovered economically and reasonably.INTRODUCTIONAs the density of cassiterite is higher than that of gangue, gravity separation is considered to be a low cost, pollution free, and effective process for cassiterite recovery (Wills, 2009). However, cassiterite is a kind of fragile mineral, over crushing is easy to take place and a large amount of slime is inevitably produced in the crushing and grinding of cassiterite. For the cassiterite slime exists in –0.043 mm size fraction, the efficiency of gravity separation decreases sharply. The production practice shows that, for the fine cassiterite, the recovery of tin exists in –0.043 mm +0.010 mm size fraction is about 13% through shaking table gravity separation, and the tin exists in –0.010 mm size fraction is almost impossible to be recovered by gravity separation. If flotation is adopted to recover fine cassiterite, the problems of high reagent dosage, high cost, environmental pollution, and poor economic benefit would take place. Therefore, the recovery of cassiterite slime is a worldwide problem. A key way to increase the utilization of tin resource and increase the economic benefit of tin mines is developing suitable beneficiation process for fine cassiterite."

Jan 1, 2016

By Lan Vu

"The Ferderber mine consists of a series of Archean gold-bearing quartz lenses within a shear zone that crosscuts the central part of the quartz diorite Bourlamaque batholith. This zone has sharp contacts with the enclosing quartz diorite, and on average strikes N70E and dips 65SE. Along the contact with the shear zone, the quartz diorite is chloritized, sericitized and carbonatized. The chlorite schist within the zone is probably derived from mafic dykes.The geometry and distribution of structural features within the Ferderber shear zone suggest a long history of repeated movements. The majority of gold-bearing lenses were first emplaced during a probable early period of brittle shear which resulted from strike-slip movement. They were then folded and pulled into boudins by a later episode of reverse movement that accompanied ductile shear. New mineralized veins were emplaced in the shear zone and deformed at this time.Mineralized veins are dominated by quartz, carbonates, tourmaline and micas. Gold is more common within pyrite where chalcopyrite is abundant and is generally in contact with both pyrite and chalcopyrite at ""triple point"" grain junctions. This intimate association suggests that copper may have played an important role in gold deposition.Recent exploration has shown that the Bourlamaque batholith is cut by many parallel or en echelon shear zones. Study of ""Landsat"" and aerial photographs has indicated a number of linear structures striking ENE-WSW and ESE-WNW which form a conjugate system. The intersection of these two structural trends presents an interesting exploration target."

Jan 1, 1990

By D. Lopez, D. L. Doerr, T. J. Drake

Automated scanning electron microscopy has been widely used in recent years for gold and other precious metals characterization. However, application of this technology is resource intensive and in most instances needs specialized technical personnel to process the samples and information. Newmont Metallurgical Services (NMS) has recently acquired an ASPEX SEM. The ASPEX SEM offers some significant benefits/improvements in sample preparation and sample processing time. NMS and ASPEX have been working together to develop an approach utilizing this technology for the minerals processing industry and specifically for gold characterization.

Jan 1, 2011

By L. Dorador

"In block caving projects, the rock mass fragmentation process plays a controlling role in the design and success of the operation. Poorly understood, however, is the secondary fragmentation that occurs as blocks of caved ore move through the draw column and interact with one another. The initial size of these blocks can be considerable, as can their strength and stiffness as the presence of non-persistent joints and veining will be variable. Intuitively, more planes of weakness within the blocks should facilitate early fragmentation, but this assumption could depend on additional factors such as contact type between adjacent blocks and loads imposed through varying heights of the draw column. This paper reports the findings from a laboratory investigation examining the role of block strength and planes of weakness on secondary fragmentation. Testing was carried out on small-scale concrete cubes of uniform size, with and without embedded planes of weakness. The results obtained demonstrate the significance of veining and other planes of weakness on secondary fragmentation under one-dimensional compression, and allow for the development and constraint of empirical guidelines.INTRODUCTIONThe fragmentation process during block caving involves the initial (primary) fragmentation of rock in the cave back through stress-induced fracturing, release and fall of individual blocks onto the broken ore muck pile. This is followed by secondary fragmentation involving splitting and rounding of blocks as they move downwards through the draw column towards the draw point. The degree of secondary fragmentation achieved involves many variables related to the mechanical properties of the rock blocks as well as different operational factors. With respect to the block properties, the presence of planes of weakness in the form of veining and non-persistent joints is a topic of special interest given the significant influence it potentially has on the overall fragmentation process. However, the inherent heterogeneity and variable size of individual blocks generated from the cave back makes it difficult to develop any empirical relationships relating secondary fragmentation to compressive loading based on insitu observations and mine data. More preferable would be to keep constant block parameters, such as shape (aspect ratio and angularity) and size, through controlled laboratory testing. This work presents an efficient technique to fabricate concrete cubes in order to keep constant different block properties. These are then tested under one-dimensional compressive loading. The objective of these tests is to emulate a tight packing condition of single blocks such as that which would occur when the air gap between the cave back and broken ore in the draw column is small. When the air gap is small, detached blocks are unable to fall and rotate but instead maintain a very tidy arrangement with minimal voids left between adjacent blocks."

Jan 1, 2015