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By Corby G. Anderson

"Laboratory testing, plant optimization, and the interpretation and application of metallurgical technologies can be tedious, time consuming and costly. This paper outlines the use of proven statistical design of experimentation software for rapid laboratory testing and optimization of operating plants with limited representative sample utilization. This results in less costly required testing, a more thorough understanding of results and the ability to simultaneously optimize several variables and outcomes at once. At the Center for Advanced Mineral and Metallurgical Processing (CAMP), this testing methodology has been used successfully in many metallurgical development and plant optimization projects thereby confirming its real world utility and application. Accordingly, several applied examples in flotation and hydrometallurgy will be outlined in this paper. This will include flotation testing of a copper gold ore, flotation testing of a copper, cobalt and gold ore, optimization of an industrial hydrometallurgical jarosite circuit and optimization of industrial nitrogen species catalyzed pressure leaching of a copper enargite concentrate.INTRODUCTIONWhile flotation technology is now 100 years old, the testing, interpretation and application of lab results can be tedious, costly and time consuming requiring extensive sample collection and preparation. In addition, recent applications like hydrometallurgical pressure leaching and associated unit operations, such as precipitation, still remain more of an art than a quantifiable science. This paper will elucidate the application of STAT-EASE Design-Expert software to minimize required laboratory testing while rapidly optimizing multiple results and outcomes in a statistically valid manner. The STAT-EASE program is based on proven design of experiment fundamentals. In this paper, the real world application of this methodology for lab testing, plant optimization and process development will be elucidated."

Jan 1, 2006

By Augustine O. Orumwense, Micheline Boisclair

"The use of stirred mill to complement tumbling mills in grinding fine grained minerals is increasingly becoming an attractive processing option. Parameters such as agitation speed, grinding media type and size, feed pulp density, and grinding time were studied in order to elucidate their impact on stirred milling. Test results showed that the parameters have a profound effect on stirred mill efficiency and operating cost. A comparative test with a tumbling ball mill was also made and the specific energies of both mills in fine grinding were analyzed. A difference of over 40% in energy savings particularly when the product size is smaller than 20 µm was obtained with the stirred mill.INTRODUCTIONIn industrial processes where very fine and ultrafine particles are required such as in chemical, ink, food, paint and lacquer, pulp and paper, plastics, pharmaceutical, metallurgical and ceramic industries, the use of stirred mills for grinding is well established. Mineral processing plants are gradually shifting focus to the use of stirred mills for fine grinding and /or regrinding purposes as the target liberation size gets very small. A number of plants processing finely/sparsely disseminated ores are known to have adopted stirred milling technology for their fine grinding needs (Enderle et al., 1997; Harbort et al., 1999; Gao et al., 2000; Davey, 2003 & 2006; Pease et al., 2006).There are different kinds/designs of stirred mills available on the market but, all can be divided into two sub groups namely fluidized and non-fluidized types. The non-fluidized stirred mills consist of Tower mill, Vertimill, Sala agitated mill (SAM), and ANI-Metprotech (SVM). These mills are characterized by their low-speed and the use of fairly coarse grinding media size, 3 – 20 mm. Hence, they are mostly suitable for relatively coarse grinding application. The fluidized type includes the Isamill, Netzsch mill and Stirred mill detritor (SMD). These mills have a characteristic high agitator speed, use fine grinding media size of 0.5 – 5 mm, and are employed in very fine grinding operations. The superior fine grinding capability of stirred mills is attributable to two main process parameters, which are the use of fine grinding media and a high mill speed."

Jan 1, 2008

By P. Scinto, P. Hudson

"Modern day ore bodies are becoming increasingly harder, more abrasive and lower grade. The Mako deposit is located in Senegal and consists predominantly of primary mafic and felsic lithology that are both very competent and very abrasive ores (Axb < 30, BWi >20 and Ai >1.0). The deposit was initially discovery in 2010 and the Toro Gold management team fast tracked the Mako Project through development and into production to achieve its first gold pour in January 2018. The comminution circuit comprises primary crushing single stage SAG milling with recycle crusher (1oCR SS-SAC). The mill reached design throughput and grind size seven weeks after first ore. The Mako project marks another successful international application of single stage milling, which represents a simple and easy to operate comminution circuit for small-to-mid size projects with a low capital cost. This paper describes the ore interpretation, comminution modelling, grinding circuit selection and design, as well as an overview of the commissioning and ramp-up of the mill.INTRODUCTION The Mako Gold Project is operated by Toro Gold Ltd., which holds a 90% interest in the project. The project is located in south-eastern Senegal in the Kedougou region, close to the Gambia river and township of Mako. The Mako deposit lies in the “Kenieba Window” of eastern Senegal and western Mali, which hosts a number of gold mining operations and development projects. The Mako Gold Project has an estimated life of 8 years with overall recoverable gold estimated at 924 koz. The process plant is designed to treat 1.8Mt/a of ore and produce 128 – 143 koz of gold per annum. Lycopodium Minerals Pty Ltd (Lycopodium) was appointed to provide feasibility studies and EPCM services for the greenfield project. Forming part of consultancy services provided by Lycopodium, Orway Mineral Consultants (OMC), a subsidiary of Lycopodium, was involved in the design, commissioning, ramp up and ongoing post commissioning support of the comminution circuit."

Jan 1, 2019

By Jr. Blanchette, Claude Bazin, Paul Blatter

"Reporting of the gold production during a month implies to estimate the mass of gold that is processed by a mill, recovered as dorés, lost to the tailings and the change of gold inventory within the plant equipments. Carbon in pulp and/or carbon in leach tanks may contain gold inventory as large as 72 000 g (2 200 troy oz) of gold which needs to be estimated from measurements obtained from sampling the material contained in a tank. Sampling and analysis introduce measurement errors that could be systematic and/or random. This paper examines the effect of measurement errors on the estimation of the gold inventory and on the variation of the inventory in the carbon in leach tanks of the Agnico-Eagle Mines Limited Lapa concentrator. Results of the analysis demonstrate that the inventory is measured with ±10% reproducibility, while the variation of inventory used for mass balance is known with ±300% reproducibility.INTRODUCTIONThe preparation of a production report implies to reconcile measured data with the constraint of material balance over the considered period of production. The sampling and data reconciliation problems were recently reviewed by Morrison (2008) and Jansen (2009a; 2009b). Typically a production report is prepared to cover a period over which the mass conservation hypothesis can be considered valid. In gold processing plants, the change of inventory can seldom be neglected and plays a significant role in material balance calculations. This is particularly true for circuits using carbon adsorption, where the complete cycle of carbon is measured in days.In a 2000 t/d gold ore processing plant, the inventory can be as large as 140 000 g of gold in gravity concentrator bins, carbon in pulp tanks and in the electrolysis circuit. This is equivalent to the mass of gold that fed the circuit during 10 days of operation with 7 g/t feed assays. The change of inventory may therefore strongly impact the production figures and especially the plant recovery at the end of a week or a month. Despite the financial impact associated with gold inventory, few publications are devoted to the subject. Bruington (1991) and Morrison (2008) discussed the problem and stressed the need for the development of reliable methods to estimate the gold inventory in carbon in pulp or carbon in leach circuits."

Jan 1, 2011

By J. -M. Bosgiraud, G. Armand, S. Dewonck, L. Richard-Panot

"The Meuse/Haute-Marne Underground Research Laboratory (URL) is located on the eastern boundary of the Paris Basin. The URL started to be built in 2000 (shaft sinking operations) in the framework of ANDRA’s (French national radioactive waste management agency) research program aimed at determining the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive waste (HLW, IL-LLW). Its underground drifts are used to study the Callovo- Oxfordian claystone layer between 420 m and 550 m in depth.The ongoing research program (started in 2006) following the “Technology Readiness Level” (TRL) Scale is more dedicated to technologies improvement and demonstration issue of the different disposal components, even if characterization and monitoring studies are still ongoing.In rock mechanics, at the main level of the URL (located at 490 m), construction and evolution of disposal cells of different size are studied for HLW and IL-LLW packages. A step by step approach, started in 2006, is carried out based on comparison of HM behavior of parallel drifts excavated/supported by different construction methods. These various configurations give insight of the influence of construction method on the EDZ extent and evolution and on the progressive loading of the support, which are key issues to design the Cigéo disposal drifts and excavations.The concept of disposal cells studied for HLW consists in horizontal steel lined micro-tunnels 80 m long and 70 cm in diameter. Several campaigns of tests have been carried out since 2009 in order to demonstrate the feasibility of excavating such micro-tunnels and study their behavior under different conditions (with and without back filling the annular gap between the rock and the casing, watertight or not casing). A full scale demonstrator representative of the benchmark concept has also been excavated, to study its behaviour under thermal loading with heat produced by electrical heaters."

Jan 1, 2015

By J. H. C. Scrimgeour, T. Toong, R. E. Hamilton

"The principles involved in the use and application of mathematical models as an aid to the development of advanced process control computer systems are described briefly. This is followed by a brief survey of known models of this kind for the simulation of mining industry processes.The main part of the paper describes a dynamic model of the flotation process developed by Canadian General Electric. Using flotation rate constants for each species of mineral and gangue, the model provides a numerical solution of the differential equations describing cell behaviour. The cell mode] is used repeatedly as a subroutine in the •over-all-plant model. The features of the cell and plant models are described.Simulation runs from the plant model show stream .assays and other indications of plant behaviour printed typically in 1-to 10-minute steps for several hours of •Operation following typical disturbances such as changes in feed rate or reagent addition rate. The simulation can :Show expected behaviour for both uncontrolled and computer-controlled plants."

Jan 1, 1970

By Ralph Harris, Qi Xia

"Gold cyanidation rates are known to be limited by the rate of oxygen dissolution in the cyanidation tanks. The effect of solids loading on the oxygen dissolution rates is not obvious and the results of previous studies are ambiguous. The present paper presents an analysis of oxygen dissolution rates using a ""spent"" commercial gold slurry diluted to various levels of solids loading. It was found, in an 170 litre stirred tank reactor using an inverted cone sparger, that under certain high loading conditions, there was a decrease of as much as 50 %, i.e., there was a halving of the rate of oxygen dissolution as compared to that in clean water. In particular, it was observed that, due to gas flooding of the impeller, there was a drop in kLa even with an increase of gas velocity. Gas holdup reached a maximum value of only 1.7 %. The total power consumption was between 0.06- 0 .10 kw/m3 within the range of gas velocity before flooding occurred. The decrease in oxygen dissolution rate with increased solids loadings is believed to be mainly due to the increase in the apparent viscosity which reduced the turbulence and shearing effect and resulted in larger bubbles and hence reduced the reaction area a. The interrelations between solids loading, gas holdup, flow pattern, power consumption, and liquid mass transfer coefficient are discussed.IntroductionThe reactors generally used in gold cyanidation are Stirred Tank Reactors (STR). Compared with other types of reactors like fluidized bed reactor and column reactor, STR is of particular importance due to its wide application in industry. It is reported that the stirred tank reactor is used for more than 50 % of the world's chemical production (Xu and McGrath, 1996)."

Jan 1, 1997

By Gordon L. Draeseke

"Before getting into more specific aspects of my talk today I should put in one disclaimer - one week in Mainland China and one day with Premier Kosygin does not make me an expert on Sino-Soviet affairs nor on Canadian-Chinese relations. Perhaps though there is a message in the fact that one meeting took place in relative openness in China and the other was at least partly in a bullet-proof limousine in Canada. I thought it might be interesting and appropriate to explain something of the forest industry to you who are engaged in the mining industry. Our industry, like yours, is based on a natural resource and the basic activity that we engage in is the extraction and conversion of that resource into saleable materials. However, the fundamental difference between our industries is that our resource is on top of the ground - easily visible and easily measurable, whereas yours is under the ground - difficult to find and, having been found, expensive to measure. A second difference is that ours is renewable while yours is extractive, and you must keep finding more to keep up reserves."

Jan 1, 1971

By K. Awuah-Offei

Long-term production scheduling optimization has been a challenging issue for the mining industry because of the size and complexity of the problem. The current planning algorithms have limitations in terms of addressing the stochastic variables underlying the mine planning problem. In this paper, an intelligent agent-based mine planning framework based on reinforcement learning is introduced. The long-term mine planning is modelled as a dynamic decision network. The intelligent agent interacts with the block model by means of a stochastic simulation and employs a Q-learning algorithm to learn the sequence of pushbacks that maximizes the net present value of the mining operation. The intelligent open pit simulator (IOPS) was implemented with an object-oriented design in Java®. A comparative application case study was carried out to verify and validate the models. The proposed method was used in planning an iron ore deposit and the results were compared to the Milawa scheduler used in Whittle® software. The outcome of the study demonstrates that the intelligent agent framework provides a powerful basis for addressing real-size open pit mine planning problems.

Jan 1, 2008

By The Staff

"IntroductionThe published information concerning treatment of uranium ores has been very limited as far as Canadian ores are concerned. Such information has dealt mainly with refining processes for concentrates or rich ores, designed to recover radium rather than uranium; these methods could not be economically applied to low-grade ores.The purpose of this paper is to describe treatment possibilities for some of the .ores that have been treated at the Mines Branch, and .to show how the character of these ores influences methods and results.What is a Uranium Ore?Prospecting for uranium has been extremely active during the past two years and a great many occurrences of radioactive minerals have been recorded. Such prospecting has been based to a large extent on the use of the Geiger counter in the fie1d. This equipment is an invaluable aid when the results are properly interpreted.Most definitely, indications of high radioactivity do not always prove the presence of a valuable orebody. First we have to determine:(1) Is the radioactivity due to uranium or to thorium. There is no immediate market for thorium.(2) Can the uranium in the ore be economically recovered.Chemical analysis is the most exact method of determining uranium content, but a fair estimate of the uranium, and also of the thorium, content can be made from the difference in gamma and beta activity. The Mines Branch guards against misinterpretation by determining both beta and gamma activities and, if more than a minor amount of thorium is indicated, then a Chemical analysis is made."

Jan 1, 1950

By K. V. Lindell

Introduction This paper describes a recent innovation in the design and construction of mine headframes. A reinforced concrete headframe was built by using sliding forms. A concrete headframe of conventional design was originally considered, but investigation of this project showed that it was doubtful if the bearing strength of the soil was sufficient to support the great weight of a structure of this type. In addition, the slope and the fractured condition of the serpentine bed-rock did not permit satisfactory piling. A conventional steel headframe with storage bins was then designed, but, due to the steel situation, delivery promises were set back many months. The concrete headframe was again investigated, and a design was adopted incorporating a circular headframe lower in height than that first considered, with skips discharging into a smaller surge bin. The upper section of the shaft collar was strengthened to result in a stable structure which would be supported by bed-rock, as well as by the concrete and steel lining of the shaft itself.

Jan 1, 1948

By Fei Dai

Musculoskeletal disorders (MSDs) are a group of painful disorders that affect muscles, tendons, nerves, joints, cartilage, and ligaments. They are a serious problem among the workforce in the United States. In the construction industry, high physically demanding tasks expose construction workers to a number of well recognized MSDs risk factors such as repetitive motion, high force exertion, and awkward body posture. Finding ways to effectively identify and evaluate risks of MSDs can significantly alleviate this problem. To this end, this paper reviews state of practice and research in the assessment of risks of MSDs among construction workers, in which a number of biomechanical models have been developed to evaluate joint and tissue loading with the aid of state-of-the-art remote sensing technologies. Findings from the review reveal that despite the advances in tracking human motion and muscle activities, current remote sensing approaches still involve sophisticated instrumentation and expensive experiment setup. These factors greatly limited the applicability of such approaches in real construction settings. How can we detect and evaluate the construction worker?s MSDs risk in real work environments? In this paper, strategies by utilizing video surveillance systems are presented, to set the stage for addressing the above question and discussing future research in real-time, marker-less, and costeffective MSDs risk assessment.

Aug 1, 2013

By The Staff

Introduction It is the purpose of this paper to discuss a number of the metallurgical improvements in the technology of copper-nickel ore treatment which have been introduced during recent years in the plants of ?the International Nickel Company of Canada, Limited. In common with other ore treatment processes, the procedure for extracting nickel and copper is changing almost continuous! y. These changes are necessitated by reason of changes in ore grades and characteristics, rising material and labour charges, and the constant drive to maximize metal recovery and to minimize production costs. It is not possible to present a comprehensive list of all the changes made, and only a selected number of the improvements in the milling, smelting, and refining operations are covered. It should be clearly understood that some phases of the procedures described have been pioneered by others in kindred fields and due acknowledgment is given to their foresight and efforts. Articles have been published over the years describing the operations of the International Nickel Company plants and the reader is referred to the Engineering and Mining Journal, Vol. 130, No. 9, November 10th, 1930, and to the Canadian Mining Journal, Vol. 58, No. 11, November, 1937, and Vol. 67, No. 5, May, 1946. Other references are the Transactions of this Institute, 1932, 1938, and 1946; Metals Technology, American Institute of Mining and Metallurgical Engineers, February, 1938, and Canadian Chemistry and Process Industries, April, 1940.

Jan 1, 1948

By J. L. Jambor, R. W. Boyle

"The Magnet Cove barite-sulphide deposit is a raking pipe-like body that replaced and partly filled a large brecciated zone at the junction of two faults at the contact between sedimentary rocks of the Horton and Windsor Groups of Mississippian age. The principal minerals in the deposit are siderite, barite, hematite, pyrite, marcasite, galena, sphalerite, chalcopyrite, tennantite, proustite, pearceite, acanthite and stromeyerite. The mineral assemblage and textural relationships indicate that the minerals were deposited from low-temperature solutions. The source of the elements in the deposit is believed to be the enclosing sedimentary rocks, with connate or ground waters as the transporting medium, and solubility products as the governing factor controlling the abundance and order of deposition of the minerals."

Jan 1, 1966

By H. Cay, J. Zachwieja, T. Esplin, R. Ravenelle, T. Olsen-Tank

Barrick Goldstrike mine utilizes a carbon-in-leach (CIL) circuit to simultaneously leach gold into solution with cyanide and adsorb the gold-cyanide complex onto activated carbon for further refinement. If the gold bearing ore contains a significant amount of native carbonaceous material, gold cyanide can be adsorbed at these sites instead of onto the desired activated carbon and the gold is effectively lost to tailings in a detrimental process known as "preg-robbing." The preg-rob effect is considerably reduced by treating the ore with a surfactant, which is hypothesized to adsorb to and passivate the native carbon surfaces. Past laboratory and pilot studies have consistently demonstrated significant gains in gold recovery after treating carbonaceous ore with surfactant. With success in bench and pilot scale testing, a plant trial was conducted at Barrick Goldstrike to evaluate the feasibility of using an alkoxylated fatty amine surfactant (Ethomeen T/12) to aid in the leaching of high preg-robbing ores. This paper analyzes the performance of the surfactant during the plant trial in addition to the problems that occurred during the trial period. Suggestions for improvement are also discussed.

Jan 1, 2014

By Guy Archambault, Réal Daigneault

"Un trait marquant du cadre tectorwstratigraphique de la Sous-province de l'Abitibi est la présence de nombreux couloirs de déformation d’extension régionale et sub-concordants au grain stratigraphique. La présence de grandes masses granitoïdes qui perturbent l'allure du grain tectonique est typique de la partie nord de la Sous-province de l'Abitibi. Des rides E-W constituées de complexes plutoniques précoces forment des reliefs structuraux agissant comme des moles résistants qui interfèrent avec la déformation régionale.Deux types de couloirs de déformation sont distingués, les couloirs de bordure et les discontinuités structurales. Les couloirs de bordure représentent des auréoles de déformation élevée qui s’accompagnent généralement d’un métamorphisme au faciès amphibolite. lls suivent /'interface entre les roches granitoïdes et les assemblages supracrustaux. Ces couloirs sont de puissance kilométrique et sont confines, surtout au sein des roches vertes, a l’interface des complexes granitoïdes d’importance. La limite entre la Sous-province de l'Opatica et les roches supra crustales de l'Abitibi est caractérisée par un important couloir de bordure issu possiblement d'un chargement tectonique irrégulier et concentre lors du raccourcissement horizontal.Les discontinuités structurales sont des failles ductiles qui se propagent surtout en direction E-W mais avec des variantes de directions SE et NE. Les discontinuités E-W se caractérisent par la présence d'une linéation d'étirement à fort angle de chute. Les discontinuités SE sont caractérisées par des linéations d'étirement horizontales et directionnelles et les mouvements observes sont system attiquement dextres. Les discontinuités NE sont des failles à comportement beaucoup plus fragile et se distinguent par des composantes de mouvement senestre. Elles sont tar dives par rapport aux discontinuités E-W et SE et ne représentent pas la symétrique du système SE.La combinaison des systèmes E-W et SE décrit un motif anastomose a l' échelle régionale. Les failles ductiles se rejoignent defaçon asymptotique, isolant des blocs peu ou pas affectes par la déformation. L'anastomose est un phénomène qui se produit a toute échelle et est reliée principalement aux Mt érogénéités et aux anisotropies 1) des forces agissantes (champs de contraintes régionale et locale) et 2) de la réponse del' empilement supra crustal (compositions différentes, fabrique initiate, propriétés mécaniques variées, niveaux d'altération).Dans le but de respecter un raccourcissement horizontal N-S, différents modelés sont proposés; ils mettent en cause soit une transpression dextre, soit des failles inverses réactivées en failles décrochèrent dextres soit des failles de chevauchement redressées."

Jan 1, 1990

By Jeanne B. Percival, Paul Ramaekers, Charles W. Jefferson, Pat A. Hunt, Eric G. Potter, Katherine E. Venance, William Davis, Sean A. Bosman

"A 10-cm thick clay-rich layer near the top of the Manitou Falls Formation of the Athabasca Group is unusual in its breccia texture, alteration, and detrital mineral composition relative to the adjacent overlying and underlying sedimentary beds. This layer is composed of angular quartz grains set in an illite >> kaolinite + dickite matrix. Deformed clay-rich fragments within the layer have very similar mineral assemblages. The presence of euhedral accessory minerals including Ti-oxides and aluminophosphatesulphate minerals points to a diagenetic/hydrothermal origin. The presence of individual grains of Kfeldspar and amphibole is unusual relative to the typical Athabasca quartz arenite; originally, these minerals were probably included in detrital quartz and subsequently liberated during fracturing. The textures and alteration characteristics suggest that this layer is a hydraulically-fractured unit, which has experienced hydrothermal fluid alteration - a possible pathway distally related to uranium mineralization Une couche argileuse de 10 cm d’epaisseur pres du sommet de la Formation de Manitou Falls du Groupe d&apos;Athabasca est remarquable par sa texture brechique, son alteration et la composition de ses mineraux detritiques qui different de ceux des couches sedimentaires sus- et sous-jacente. Cette couche est composee de grains de quartz angulaires dans une matrice composee d’illite >> kaolinite + dickite. Des fragments deformes riches en argile dans cette couche presentent des assemblages mineraux tres similaires. La presence de mineraux accessoires idiomorphes dont des oxydes de titane et des aluminophosphates-sulphates suggere que ces derniers ont une origine diagenetique / hydrothermale. La presence de grains de feldspath-K et d&apos;amphibole est inhabituelle comparativement aux arenites quartziques typiques de l’Athabasca; initialement, ces mineraux constituaient probablement des inclusions dans le quartz detritique qui ont ete subsequemment liberees pendant la fracturation. Les textures et les caracteristiques de l&apos;alteration suggerent que cette unite a subi une fracturation hydraulique et a ete alteree par un fluide hydrothermal - possiblement en lien avec les effets distaux de mise en place de la mineralisation en l&apos;uranium."

Jan 1, 2013

By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days&apos; plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years&apos; operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984

By Hans Lundberg

Introduction Today, geophysical exploration is recognized as a special science wedged between geology and mining. Universities and technical institutes have special professors teaching geophysics applied to oil and ore prospecting. The list of literature on geophysical exploration has grown from practically nothing at all some twenty-five years ago to ~ several thousands of books, some of them very imposing volumes. Most of the methods now used have been developed since the first World War, and very large systematic exploration campaigns have been carried out in many places, in many countries. It has been rather difficult to obtain enough information as to what is going on in Canada. However, since the Associate Committee on Geodesy and Geophysics of the National Research Council became more actively engaged in promoting geophysical research, it may be easier to obtain information and, in the future, the quarterly issued Canadian Geophysical Bulletin may throw considerable light on the current geophysical activities in Canada. Some twenty crews have been engaged the last few years in geophysical prospecting for ore. In the United States, between 500 and 600 crews are employed exclusively in geophysical prospecting. Most of these, however, are engaged in oil exploration. During the winter 1942-1943, the German Government employed some fifty crews on geophysical exploration, and some ten crews were working for private enterprises.

Jan 1, 1948

By M. Kuyumcu

After German reunification the mining industry in former East Germany was profoundly restructured. Beside privatization of profitable companies the public sector took over responsibility for the mining operations to be shut down. Therefore state-owned companies cope with technical, ecological, and social challenges. The rehabilitation and reclamation has to rededicate former mining areas to new use and provided new jobs as well. In the lignite mining districts there are around 100,000 ha of mining area, a mining caused disturbance to the groundwater balance and to the system of surface water bodies of approx. 390,000 ha. They are called the largest landscape construction site in Europe. In addition to the results and diverse experience achieved over the past 23 years, a description will follow of our new challenges and of an outlook on remaining tasks. This article will describe the financing, as well as aspects of the jobcreation policy arising from lignite industry remediation.

Aug 1, 2013