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By V. C. Wansbrough

First, permit me to say with what very great pleasure we find ourselves assembled in this most ancient and honourable city of Quebec. It is a city which we deeply respect as the fountain-head of the culture of French-speaking fellow citizens, and the seat of government of a province which is steadily recording new achievements in Canadian mining. Such achievements prove what can be accomplished when enlightened and progressive government policy, technical and scientific competence, and private initiative pull forward together in harmonious rhythm. It is a most happy and auspicious event also that the guiding control of the affairs of the Institute and of the fine traditions of provincial administration have for the past year been united in the person of our honoured President, Dr. A. O. Dufresne. This year, again, we have bad prepared for us by our hosts a splendid programme of technical sessions and social entertainment. Each year we pay an unspoken compliment to the Institute, expecting as a matter of course nothing but the highest standards in both these spheres. In its annua1, semi-annual, and regional meetings, in the constant activity of its local Branches, the Institute continues with marked success to perform its great dual service, social and educational. We are all its beneficiaries to the extent to which we choose to profit by participation in its affairs. But, one imagines, to none are the advantages of Institute membership more valuable than to young men embarking on their professional careers.

Jan 1, 1951

By J. Gray, J. Peck

As the turn of the century approaches, traditional open pit mining methodologies and processes are being modified through the introduction and use of new technologies. As in other industries, the personal computer is dramatically changing the traditionally conservative mining industry by allowing mines of varying size and capacity to increase their productivity and efficiency through the use of easy to use, office software. Computer-based monitoring and control systems are also being used more frequently to measure and optimize, in real-time, the performances of operating equipment. When communicated to an end-user, this information can provide accurate and timely answers to questions of how much, where, when, and by whom. This capability forms the foundation of a more comprehensive, proactive management and planning facility where, ultimately, information acquired from the producing equipment will be used to optimize and control machine and human activities. As these technologies mature and become essential tools in a mine, they will eventually serve as the basis for more robotic and autonomous mining operations.

Jan 1, 1999

By H. L. Snyder

This paper outlines the approach to the underground construction work involved in the Churchill Falls Power Project. It is the first in a series of papers which CIM Bulletin plans to publish as the different 11hases of this large-scale operation evolve.

Jan 1, 1968

By M. H. Allan

"This paper presents the geographic and geological setting of Saskatchewan Power Corporation's Poplar River Mine in south-central Saskatchewan, about 8 miles from the U.S. border. Generally the mine, which is being expanded to four million tons per year, is in an extremely disturbed geological area with severe dewatering problems. The lignite coal, which is strip mined, is supplied directly to an electric power generating station by means of a 7-mile unit-train private railroad.A number of unique reclamation and socio-economic problems were encountered because of the proximity to the U.S. border and because of the lack of experience of the regulatory authorities in projects of this kind. These are described in some detail, as well as the performance of one of the largest draglines in Canada. IntroductionThe Saskatchewan Power Corporation is a publicly owned utility which has the franchise to supply electricity and natural gas to all customers within the boundaries of Saskatchewan.Saskatchewan is a province which can almost be divided in two: the populated southern portion, principally devoted to farming, and the northern portion which is mostly on the Precambrian Shield and consists of lakes, rocks and muskeg. This portion is largely uninhabited except for a number of small villages. However, in the last few years there has been considerable mineral exploration and development, notably for uranium. This has helped considerably in the diversification of the basic agricultural economy of the province.Saskatchewan consists of 251,700 square miles, 761 miles north to south and an average of 335 miles east to west. It has a population of approximately 960,000, giving a population density of four persons per square mile. The Saskatchewan Power Corporation supplies 357,249 electrical arid 221,378 natural gas customers."

Jan 1, 1982

By Oakley B. Gwillam

The study of leached outcrops as an aid in determining the character of mineralization beneath the surface is in its infancy. Practically all the work on this subject up to the present has been applied to the 'porphyry' copper deposits of the southwestern United States. Some work has been done also on the zinc-lead solid sulphide deposits of the western United States. The question has been asked, "Can this study be applied, and would it have any practical application, in northern Manitoba?" When one realizes the size of the unprospected territory in this Province and the consequent need for a cheap and rapid method of interpreting the countless outcrops which occur in order to discriminate between valueless iron sulphides and valuable sulphides of the base metals, it is readily seen that the study is of great value if it can be applied with a reasonable degree of surety. Augustus Locke, well known economic geologist of the southwestern United States and a pioneer in the study of leached outcrops of disseminated copper ore, has written much on the subject. Messrs. Blanchard and Boswell in a series of articles have dealt with the leached outcrops derived from lead and zinc sulphides in the western United States. Since this paper is essentially a comparison between the leached outcrops of the southwestern United States and those of northern Manitoba with the purpose of testing the adaptability of the study in this Province, an outline of the criteria used in the southwest will be of value to the reader.

Jan 1, 1930

By T. E. Warren, K. W. Bowles

"IntroductionTHE PROBLEM of producing synthetic liquid fuels from coal and other raw materials is of increasing importance in Canada as well as in the United States. This is due, to a large extent, to the continually increasing demand for gasoline and other liquid products which are now obtained solely from petroleum. The United States has reached a position where domestic supplies of crude petroleum must be augmented by imports and Canada is still a long way from self-sufficiency. In the event of war, there might well be an immediate need to find supplementary sources of liquid fuels. It is, therefore, expedient to consider alternative sources of production now -well in advance of the time when supplies of petroleum may prove inadequate to meet requirements.The purpose of the present paper is to give a short review of the history of liquid fuel production from coal, to describe briefly the research sponsored by the Federal Government on the coal hydrogenation process, and finally to evaluate the present status and future trend of the synthetic fuel industry, with special reference to necessary research work.History of the Oil-From-Coal IndustryThe history -of coal liquefaction began in 1913, in Germany, with the work of Frederick Bergius. His first approach to the subject was not deliberately planned."

Jan 1, 1952

By P. Tarassoff

Extractive metallurgy is concerned with the winning of metals from their ores and concentrates. It is therefore not unexpected that extractive metallurgy in Canada has always been closely linked with mining. The discovery and exploitation of new orebodies has provided the impetus for the building of many of our smelters and refineries - past and present - and for the development of new metal extraction processes. The purpose of this paper is to provide a brief overview of those early metallurgical developments, and to highlight the continuing expansion and diversification of the Canadian metallurgical industry.

Jan 1, 1999

By Laszlo Imreh, Pierre Trudel, André C. Tessier

"The Siscoe gold mine is ranked as the fourth largest mine in the history of the Val d' Or mining district with a total production of 27.4 tAufrom1929 to 1949. Most of the gold mineralization occurred in quartz veins, hosted in a small (.69 km2) intrusion of altered quartz gabbro known as the Siscoe stock. The southern contact of the Siscoe stock is crosscut by a major shear zone (the ""K"" zone) trending 295/80 NE and from which gold mineralization was also exploited within the limits of the stock. Field and petrographic observations of the Siscoe stock combined with chemical analyses of major, trace and rare earth elements of the stock and its volcanic host rocks (Dubuisson Formation) suggest that:The Siscoe stock comprises four alteration facies formed from a homogeneous precursor: 1) the actinolite - Mg-chlorite facies, characterized by low FeOt,Na2O andTiO2 , and highAlp3 and MgO; 2) the albite- Fe-chlorite facies, containing high concentrations of FeOt and Nap; 3) the Mg + Fe-chloritefacies, which is transitional between the actinolite- Mg-chlorite and albite- Fe-chloritefacies; 4) the carbonate-chlorite facies, which consists of rocks that were subjected to extreme hydrothermal alteration, is spatially associated with mineralized veins and part of the K-zone. The first three facies are depleted in SiO 2, CaO and Au, and enriched in MgO, relative to fresh rocks of the Siscoe stock and the equivalent rocks of the Dubuisson Formation.Hydrothermal fluids introduced mainly along the K-zone ""channelway"" induced three types of element remobilization, resulting in the various alteration facies: 1) redistribution of elements within the stock from one facies to another (e .g., FeOt, Nap, Ti02 migrated from the actinolite- Mg-chlorite facies to the albite- F e-chlorite and Mg + Fe-chlorite facies); 2) remobilization of elements from the intrusive rocks into veins (e.g ., SiO 2 and CaO ); 3) introduction of elements by hydrothermal fluids in rocks of the Siscoe stock (e .g., Al2O3, MgO, H2O, CO2 and FeOt).The Siscoe stock and the Dubuisson Formation form part of the same tholeiitic suite. Similarly, the Bourlamaque batholith and the Val d'Or Formation belong to a single calc-alkaline suite. In view of this relationship, dissimilarities between the petrochemistry of the Siscoe stock and the Bourlamaque batholith suggest that the two intrusions are not co-magmatic.Finally, gold may have been leached from rocks of the Siscoe stock and remobilized into the quartz-carbonate mineralized veins. In order to account for the total production at the Siscoe mine, approximately 1.2 km3 of the Siscoe stock is thought to have been partially leached of its gold."

Jan 1, 1990

By Michel Chouteau

"A very conductive zone was revealed in 1977 and 1978 by magnetotelluric (MT) measurements carried out near Ste-Mathilde, 6 km northeast of La Malbaie . In order to identify the structure causing the anomaly, thirty-five MT soundings were recorded in 1980 and 1981 on and around the conductor within a radius of4 km. Results confirmed that the conductor is of limited extent (less than 2 km by 0.4 km). The proposed model is a highly conductive vertical slab, the top of which is within 200 m from the surface. At a depth of approximately 825 m this structure joins a conductive layer which extends to the northwest but not to the southeast. The large conductivities and the depths involved can only be explain ed by a fractured zone flooded with electrolytic solutions, by graphite veins or by metallic mineralization (sulphides). The former seems to be the most likely hypothesis because an EW fault running across this zone could have allowed percolation of water and the leaching of disseminated pyrite out of a mylolisthenite filling the fault.IntroductionLa Malbaie is located 130 km northeast of Quebec City on th e North Shore o f the St. Lawrence River (Fig. I). Four major groups o f rocks have been mapped in this area: charnockitic rocks to the west , granitic rocks in the north east and southeast, gneiss and pegmatites northwest and south of La Malbaie , and Paleozoic sediments in the Clermont-La Malbaie Valley and along the shore of the St. Lawrence River (Rondot, 1966). Two major features dominate the structure of the region: Logan ' s line , a major thrust fault beneath the St. Lawrence which separates the Grenville Province to the north from the Appalachian regime to the south, and the Charlevoix Crater , a large Paleozoic impact crater that created an almost perfect annula r structure centred on Mont des Eboulements (Rondot, 1970). Ste-Mathilde is a village lying 6 km northeast of La Malbaie, just outside the ring-like graben zone caused by readjustments after meteorite impact. The survey area spreads over a granite body which is more than 2 km long and 0.6 km wide, surrounded by a wide migmatite zone which is injected by many bodies of pegmatite, the latter likely related to the granite body (Fig. 2). A zone of leptynites lies west of the area. An east-west trending fault (FA1) related to the Charlevoix Crater runs mid -way across the survey area; a second parallel fault (FA2) south of FAI separates the gneissic rocks from the Paleozoic sediments. The overburden is usually thin with outcrops frequently encountered except for the centre of the survey are a where 10 m of glacial sediments are expected (E. Gaucher, 1982, personal communication)."

Jan 1, 1985

By T. M. Siew

"This paper begins with a brief discussion of the geology of the Newfoundland Zinc Mine area. The results of groundwater studies and pumping tests are then presented. It was decided that groundwater in the mine could best be controlled by conventional sump pumping and grouting. The system is fully described, as well as plans for improvements on the method. LocationThe Newfoundland Zinc Mine is located in the Great Northern Peninsula of Newfoundland, six miles northeast of Daniel's Harbour. The mine is situated at an elevation of approximately 350 feet above sea level, 5 miles farther inland , west of the long range of mountains which rise abruptly with elevations of over 2,000 feet above sea level.GeologyThe ore deposits occur in lower Ordovician carbonate rocks that form part of the stable St. Lawrence platform, which is mainly composed of (1) the lower Cambrian Labrador group, (2) the upper Cambrian to lower Ordovician St. George group, (3) the disconformity overlying Middle Ordovician limestones and shales of the Table Head formation and, (4) two overlying klippen composed of Cambrian and lower Ordovician rocks.The ore deposit is a Mississippi Valley type of the Tennessee variety, having proven are reserves of 5.3 million tons averaging 9.70/0 zinc from eleven ore zones which exist in an area of 5.5 square miles.Among these ore zones, the L zone is the major underground mining area, and is by far the largest of the known deposits. It has proven are reserves of 3.4 million tons with 11.5% zinc; this underground development has been inprogress since 1974.Stratigraphically, the orebody, which occurs about 300 feet below the disconformities between the Table Head and St. George formations, is situated in the upper St. George formationof lower Ordovician age.The upper St. George formation of the L zone is divided into three main units (Fig . I) : the underlying lower limestone the middle grey dolomite pseudo breccia unit and the overlying siliceous dolomite unit. In this area of the mine, the beds of the St. George formation dip gently west to northwest to 10 to 15 degrees. The orebody, which is generally strata controlled with a southwesterly plunge and which has the form of thin, narrow, but elongate, en-echelon ore bed s, is contained in grey dolomite pseudo breccia. Its dimensions vary from 50 to 900 feet in width and 8 to 120 feet in thickness, and the over-alllength exceed s 6,000 feet.The surficial deposit of the area is a till comprising a heterogeneous mixture of sand, gravel, cobbles and boulders, with an average depth of 20 feet."

Jan 1, 1980

By K. M. Deen, E. Asselin

Hydrometallurgical processes, i.e., Cu extraction from a mineral concentrate and Zn electrowinning, are coupled in a battery-like system. A naturally-sourced CuFeS2 concentrate mixed with activated carbon is used as a positive slurry electrode separated by a membrane from the negative compartment. The Zn is deposited on the negative Al current collector from the circulating solution containing 100 g L–1 Zn2+ in 0.2 M H2SO4. In this battery-like system, both CuFeS2 oxidation and Zn deposition are possible during the charging cycle. The additional benefit of this setup is the energy storage if discharged by re-dissolving the Zn in the negative compartment. Cyclic charge/discharge testing revealed oxidation of the mineral concentrate supported by the Zn2+/Zn redox reaction. The coulombic and energy efficiencies increased monotonically to 95.6% and 43%, respectively, with approximately 7% Cu extraction during the first 10 charge/discharge cycles (completed in 2.4 hours). The discharge energy density also increased from 2.7 to 36.2 mWh L–1. In the following 90 cycles, the low energy (~14%) and coulombic (~33%) efficiencies that were obtained confirmed the progress of irreversible reactions e.g. Cu extraction from the mineral concentrate. Overall, approximately 16% Cu was extracted from the mineral concentrate over 100 charge/discharge cycles (or about 12.2 hours). INTRODUCTION Chalcopyrite (CuFeS2) is the main economic copper-bearing mineral, which is generally processed through pyro-metallurgical methods to produce Cu. However, environmental challenges with smelting, depletion of high-grade ores and a large number of impurities (some toxic) have resulted in continued research aimed at the development of hydrometallurgical technologies to process CuFeS2. There are a number of different proposed hydrometallurgical routes in the literature to treat CuFeS2 concentrates, but only a few have attained commercial acceptance (Dreisinger, 2006). Zn is another commercially important metal that is mainly produced via acid leaching of roasted sphalerite (ZnS). The pregnant leach solution is rigorously purified to remove all the soluble metal impurities, particularly those that are electrochemically more noble than Zn and present large kinetic activity towards H2 evolution (Hu & Piron, 1992; Mackinnon, Brannen, & Fenn, 1987; Mureşan, Maurin, Oniciu, & Gaga, 1996). Metal impurities such as Cu, Co, Ni, Cd, Pb, Sb, As, Ge and Fe etc., if they exist in the leach liquor beyond the tolerance limits, can decrease the current efficiency during electrowinning and deteriorate the deposit quality (Alfantazi & Dreisinger, 2001). A complete flow sheet, describing the process steps of Zn metal production from mine site to pure metal is presented elsewhere (Brown, Meisenhelder, & Yao, 1983).

Jan 1, 2019

By Chun-Sheng Liao, Chun-Hua Yan, Sheng Wu, Fu-Xiang Cheng

"INTRODUCTIONChina is providing more than 90% of the rare earth products consumed in the whole world. Acidic extractants are commonly used in the extraction separation of rare earths. Saponification of the acidic extractants by basic substances is usually necessary for the purpose of increasing and stabilizing their extraction capacity, and meanwhile inorganic acids are required for both scrubbing and stripping. Thus acids and bases are the main consumed chemicals, and the resulting salts are the main pollutants generated by rare earth separation processes. Currently, due to increasing environmental concerns in China, rare earth solvent extraction separation techniques are being developed to reduce both consumption and emission of chemicals, which is driving the developments on both theories and processes for solvent extraction separations.In the 1970s Prof. Xu et al. developed the Theory of Countercurrent Extraction (Xu, Li, & Yian, 1985). In recent years, the development of novel processes for rare earth separation has moved beyond the earlier theory. One rare earth separation process, the so-called hyperlink process, has been developed in the past decade and proven in industrial practice to dramatically reduce both the consumption and emission of chemicals during multi-component solvent extraction separations, and therefore is now widely used in the Chinese rare earth separation industry (Liao, Wu, Cheng, Wang, Liu, Zhang, & Yan, 2013). The present article will give a brief review of the development of the theory of the hyperlink processes, and the hyperlink separation flowsheets for typical rare earth mines in China designed using the theory.HYPERLINK PROCESSES (LIAO et al., 2013)A flowsheet of multiple-component separation consists of a couple of separation units. The units of a conventional flowsheet separately consume chemicals for saponification and scrubbing and discharge wastewater with resulting salts. In contrast, the separation units in a hyperlink process are hyperlinked and thereby the chemical demands of the whole flowsheet are decreased. For a feed containing t components of A1, A2, …, and At, it has been proved in theory that the separation mode of (AtAt-1…A2)/(At-1At-2…A1) is preferred in a single separation unit. The hyperlinking between separation units can have two forms. The link between two units locating at a same separation level, such as between (A4A3)/(A3A2) and (A3A2)/(A2A1), is known as horizontal hyperlinking. The link between two units located on different levels, such as between (A4A3A2)/(A3A2A1) and (A3A2)/(A2A1), is known as vertical hyperlinking. Both the hyperlinking forms have been proven to save chemical usage and consequently to lower the pollution emissions in industrial practices as well as in theory."

Jan 1, 2016

By Silvana Costa

In the last two decades, there have been nearly no new mining towns built in Canada. Governments and mining companies have viewed long distance commuting (LDC), commonly known as fly-in-flyout or fly-in mines, as a way to avoid problems associated with building a new community and providing for its sustainability after mine closure. LDC is also considered more cost-effective than building a mine town. The intensification of the use of LDC in the Canadian mining sector has been quite rapid, particularly in northern regions. However, LDC has implications to employees, their families and communities, which deserve further examination, particularly considering the significant expansion in Northern mining and Aboriginal participation in this sector. This paper presents a review of the major issues in long distance commuting, both from an industry and community perspectives. It is a result of preliminary investigation for a PhD research project that will be pursued by a Bridge Fellow and UBC Mining Sustainability Working Group member, and guided by an interdisciplinary research team at the University of British Columbia (UBC). The Bridge Fellowship Program is research-training program linking the UBC?s Faculties of Medicine, Engineering and Graduate Studies. Its mission is to develop creative evidence-based prevention measures for public, environmental and occupational health problems. The SWG is an interdisciplinary student group based in the UBC Department of Mining Engineering, committed to respond to the complex sustainability-related challenges currently faced by the mining industry. In other to pursue this project, it is paramount that industry and local communities alike participate in the development and clarification of research questions as well as in the research design. It is hoped that this paper will function as an invitation for industrial and community partners for such study. The main themes identified for this research are occupational health and safety of LDC employees, family life impacts and community health impacts of this model of resource development.

May 1, 2004

By E. C. Grunsky, B. W. Smee

"The development of low-cost, rapid multielement analytical techniques has generated large geochemical databases in many exploration programs. When a sampling program consists of several thousand samples, the resulting data matrix is enormous and effective interpretation using all of the elements individually becomes burdensome. However, the application of multivariate statistical techniques can extract geochemical patterns related to the underlying geology, weathering, alteration and mineralization. Imaging the results over topography enhances the interpretation of these patterns. Examples of this approach are shown from mineral exploration programs in Canada and Mexico. IntroductionThere has been a dramatic change in the effectiveness of using geochemical survey data in the past ten years. This is mostly due to:• lower cost of geochemical analysis;• lower detection limits;• new methods of multi-element analysis;• a marked decrease in the turnaround time;and• the intelligent use of computers in presenting geochemical data.Geochemical surveys commonly have two objectives: locating abnormal concentrations of ore-forming or pathfinder elements and characterizing the underlying host lithologies. Geochemical surveys often employ a wide range of sample media that may typically include whole rock lithogeochemistry, various soil horizons, till and basal till sampling, stream sediments, lake sediments, and various forms of weathered regolith. Each of these sample media will exhibit a unique element distribution that must be factored in the interpretation phase of a geochemical survey study. This can become a cumbersome process if univariate data handling methods are employed."

Jan 1, 2003

By T. Peters, W. C. Ferguson

"Shebandowan is about 600 miles west of Sudbury and 50 miles west of Thunderbay close to the trans Canada highway. Shebandowan Lake is about 38 miles long. The ore body is located between No. 1 and No. 2 shafts at the lower end of the lake. The economic mineralization lies between 200 and 2000 feet below. Years ago development of this ore body would probably have entailed draining the lake and using the open pit method to mine the ore.The water of Gold Creek which flows into Lake Shebandowan is representative of all local waters and is very close to rain water in purity. It is obvious that any industrial water discharged would have a measurable impact on the local water. The dissolved solids content is low and consistent with what is normally found in northern Ontario.A Koepe headframe is the only visible evidence of the mine from the lake. The Koepe headframe is esthetically pleasing and quiet in operation. The structure is of concrete to control noise. Noise from ore dumping is controlled by dumping underground to an ore pocket 400 feet below the surface. A 3600 foot conveyor belt carries the ore underground to the mill and is out of sight of the lake and the cottagers. The main objective to all our environmental efforts has been to preserve the natural beauty of the region. The mill is housed in a conventional metal-clad-siding building painted in esthetically pleasing colours. A single service building houses warehouse, dry storage and offices. The area surrounding the mill and service building is paved or grassed and drainage from this area is collected and pumped to the tailings area. Air intake silencers are installed on the compressors which are mounted at the back of the mill. Sound measurements taken on the lake indicate that noise suppression is excellent."

Jan 1, 1975

By R. V. Typliski, G. J. Labarre

"Hudson Bay Mining and Smelting Co., Limited, Flin Flon, Manitoba, Canada, has developed a metallurgical wastewater treatment system employing two-stage lime neutralization, sludge recirculation and conventional mechanical thickening.Laboratory investigations, initiated in 1970, led to the construction of a pilot-scale minewater treatment plant, at Schist Lake Mine, in early 1971. This plant, treating 600 cubic meters/day wastewater containing 30-60 mg/l zinc, demonstrated metal extraction efficiencies of 99% under normal operating conditions.On the basis of this pilot work, a second pilot-scale treatment system was established in 1975 at the Flin Flon metallurgical plant to treat zinc refinery process waste water. Through numerous improvements, including automatic control equipment, the system has evolved to a full-scale operation capable of treating 800 cubic meters/ day wastewater containing 4-11 gm/l zinc. Treated effluent contains 0.2-20 mgll zinc. Hydroxide sludge produced returns to the metallurgical process for recovery of metals while clarified effluent discharges to waste.With the system, Hudson Bay Mining has achieved its original goal: the reduction of environmental contamination, while realizing ii return from metal recovery."

Jan 1, 1980

By T. Salman

Most authorities agree that the dissolution of gold from an ore takes place according to the Elsner equation first stated in 1846. The main requirements for the dissolution reaction to proceed are:(1) that the gold be clean.(2) that the gold be exposed to the solution.(3) that the cyanide solution be active, i.e., not over loaded with impurities which could retard or inhibit the reaction.(4) that an adequate supply of oxygen be available (from air).When the above conditions are met, cyanidation becomes basically a mechanical operation.Minerals such as quartz, calcium carbonate are relatively inert to cyanide though they may give rise to mechanical troubles. Most ores present an assortment of chemical problems, depending upon the constituent present, which react to the solution to varying degrees. It should be borne in mind that minerals which are disturbing to the operation, though present in small amounts, usually exceed the weight of the gold by several hundred times. In addition, the application of flotation and other forms of concentration to gold ores, previous to cyanidation, concentrates not only the gold, but also the other heavy minerals and these complicate the chemistry of the process.

Jan 1, 1975

The North Saskatchewan River flows southwest to northeast through a 22-km-long valley in the City of Edmonton, supplying the drinking water to dozens of downstream communities. During heavy rains, combined sewers occasionally overflow into the river, which has a significant negative impact on the water quality and the sensitive environment. The West Edmonton Sanitary Sewer (WESS) W12, a syphon connecting the Rat Creek Trunk to the Gold Bar Wastewater Treatment Plant across the river, was designed and constructed to take the overflow to the wastewater treatment plant. Due to the complexity of the project, various 3D technologies were applied to facilitate decision-making processes. 3D models were developed for design review and design conflict detection, while 4D models were established to help create a robust construction schedule. Construction sequencing animation was used to convey design intents and demonstrate construction stages to contractors and workers. The combined applications of 3D technologies helped the project team to identify critical issues, and assured effective communication among engineers, management, contractors, and other parties. Therefore, it provided more opportunities for the success of the project.

Aug 1, 2013

By Brian W. Mackenzie

"This paper briefly outlines the characteristics which should be considered in assessing the economics of mineral exploration, and illustrates such an assessment by using data from the Canadian base metal sector. Implications for the sector are found to include the following:(1) base metal exploration has the potential to create a substantial amount of new wealth;(2) investment incentive for exploration under current conditions is not unattractive over-all;(3) because of existing taxation policies, there is much more incentive for large companies to explore than for smaller enterprises;(4) succesful exploration is sensitive to the size, financial resources and organizational structure of the exploration entity;(5) the general level of recent exploration expenditures should be adequate to maintain the current rate of production and perhaps to support very modest growth; and(6) there is an important opportunity for growth in the sector.The findings of the study suggest that government policies should be made more flexible, in order to take into account the risks associated with exploration and with price fluctuations in the base metal sector. Recommendations are also made concerning improvements in provincial regulations for disclosure of exploration information."

Jan 1, 1981

By E. I. Vargha-Butler

The determination of surface tensions and contact angles of coal particles is of great interest for coal beneficiation processes such as froth flotation and oil agglomeration and for the inclusion of coal particles into oil droplets as a means of enriching the fuel. Methods for contact-angle measurements on small irregularly shaped solid particles have not been available in the past. Therefore, we recently developed a novel technique to determine contact angles and surf ace tensions of coal particles. Two types of bituminous and one type of subbituminous coal particles have been tested. The technique used is called the freezing-front technique and it considers the behaviour of the test particles (in the range of 20-250 pm) at the solidification front of carefully selected, well-defined solidifying melts (matrix materials) such as thymol, biphenyl, naphthalene, salol and 2-phenyl phenol.The results show that the technique works well, providing quantitative and detailed information on the wettability of coal particles. The sensitivity of the method is so high that a difference in contact angle of approximately 4 degrees between the smaller and the larger particles is clearly registered.

Dec 1, 1981