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By Yve Potvin, Fabien Miller, Deni Jacob

"The potential benefits of measuring the volume of excavated open stope are enormous. By comparing the actual excavation of the orebody contour, it is possible to determine the “real"" amount of mining dilution, as well as the ore left in place. Noranda Technology Centre (NTC) has developed a stope survey system that allows for rapid and efficency measurement of underground excavation volumes. The system comprises a commercial laser (EDM), a set of lightweight rigid rods, an automated scanning device, a hand-held data logger and Autocad-based software for volume calculation and drawing manipulations. This system is an invaluable tool for the optimization of mining practices and could also be used for the delineation of caving areas. IntroductionDilution is the most common and devastating mine disease. In some instance s it could systematically cripple the profitability of an operation, and in more extreme cases, it could become a terminal disease. The Northern Miner Journal (1988) reported that many operations have closed because of uncontrolled dilution, before they even completed their first year of production. Other studies (Pakalnis, 1986) have shown that approximately 40% of all underground operations have more than 20% dilution. Considering that every ton of dilution costs in the neighbourhood of $25, the total direct cost of dilution to the Canadian mining industry may easily exceed one hundred million dollars per year.The dilution problem has been a major concern to Noranda Minerals for some time and in 1984 a comprehensive geomechanics research program was created at the Noranda Technology Centre (NTC) in Pointe-Claire, Quebec. New empirical stope dimensioning techniques, improved cable bolting techniques and sophisticated ground control instrumentation projects (among others) contributed to improve the situation at Noranda.A new tool which can have a very significant impact on the ""war"" against dilution is being developed by the Noranda Technology Centre. The laser stope survey system allows for a rapid, precise and efficient measurement of underground excavation volumes. By comparing the excavation planned with the volume excavated, it becomes possible to determine the ""real"" amount of mining dilution as well as the amount of ore left in place. This system may also allow for early detection of a dilution problem. As with other diseases, early detection provides the best chance for a fast and total recovery."

Jan 1, 1992

By D. O. Tansey

This paper will describe the mechanisms involved in delay blasting and how they are applied with the use of D.S.B. It will examine the control of potential damage resulting from detonations, and show how good fragmentation and efficient recovery of this material blasted can be achieved

Jan 1, 1979

By T. Eger

Load Haul Dump vehicles (LHD) are extensively used in underground mining however equipment design and operating conditions contribute to restricted operator?s visibility. The inability to clearly see people, objects or hazards around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines visibility assessments are traditionally completed in the field. However, field methods are unable to evaluate visibility under dynamic operating conditions and are limited in their ability to provide feedback on the impact of various operator characteristics such as sitting height, for example. Results of this research show computer simulation and virtual reality can be successfully used to evaluate visibility during the operation of LHD vehicles. In order to benefit from virtual reality applications the work environment, LHD vehicle and human posture need to be represented as accurately as possible. A computer simulation program with ergonomic ana lysis features, Classic JACK 3.1, was successfully used. Threedimensional CAD models of LHD vehicles were developed from manufacturer specifications and pictur es taken from LHD vehicles currently in use. The LHD models were imported into the JACK environment, a digital human was positioned in the cab of the LHD vehicle and the vehicle and human where driven over a typical mine route. Real-time feedback in the JACK program was used to identify what the operator could see under different operating conditions. Machine characteristics and operating scenarios resulting in impaired visibility were successfully identified with this method. The JACK program can also provide real-time feedback on the human?s joint forces and torques, strength requirements, postural comfort, and metabolic energy expenditure. As a result, this method could be used to successfully evaluate musculoskeletal injury risk factors along with system design recommendations to improve workplace safety and productivity in any setting. The LHD VRML files imported into JACK have also been combined with environment files into other VR software packages (e.g. Maverik) to view in a VRL facility, managed by MIRARCO at Laurentian University. The VR models using these packages can be viewed in stereo to provide better appreciation of spatial visibility issues.

May 1, 2003

By G. Macfarlane

"In 1985, a crushing plant, located in the feed preparation area of Kidd Creek's copper smelter, was modified. The plant, which originally had treated only copper-bearing materials for the smeller, at a rate of 10 tonnes per hour, was expanded to 40 tonnes per hour capacity and modified to treat silica ores to meet the smelter’s flux requirement and also gold ores from the company's Hoyle Pond property. In the storage area adjacent to the crushing plant a 300 tonne per day gold mill was constructed.This paper outlines the construction and first year of operation of the crushing plant and gold mill with emphasis placed on the capital and operating advantages to be gained by utilizing an existing metallurgical infrastructure.IntroductionThe Kidd Creek Mines Ltd. copper-zinc-silver orebody is located 24 km north of Timmins, in Northern Ontario . Mining of this massive sulphide de posit commenced in 1966 and, in the ensuing years, a concentrator and zinc plant were constructed at the metallurgical complex, approximately 17 km by rail from the mine site . At this same site, in 1981, a copper smelter and refinery were commissioned. The smelter which utilizes the Mitsubishi smelting process for the continuous production of blister copper from copper concentrate, has been comprehensively described in previous papers.At the time of the smelter construction, a small (10 tonnes per hour) crushing plant was installed in the smelter's feed preparation area. This plant was used to treat the copper-bearing revert material produced by the smelter, and, apart from periods when slags and matte were produced through furnace drainage at the end of each operating campaign, it was generally under-utilized. This fact, together with the requirement to devise a more cost effective method of providing silica flux for the smelting operation, was the basic rationale for modifying and expanding and crushing plan t. At the same time, development at Kidd's Hoyle Pond orebody had progressed to such a stage that a gold mill of 300 tonnes per day was warranted."

Jan 1, 1988

By J. F. Liu, L. Chen, C. P. Wang

"Calcite-cemented joints abound in the rock masses of Beishan area, which is the most potential area for the high-level radioactive waste (HLW) disposal of China. The mechanical properties of Beishan granite containing a calcite-cemented joint with a dip angle of 82° was investigated under uniaxial compression and the acoustic emission (AE) characteristics were also studied in this paper. Compared to intact granite, the calcite-cemented joint caused a decrease more than 50% in uniaxial compressive strength and a decrease more than 90% in shear strength. The Young’s modulus was also decreased, while the circumferential deformation of jointed granite was sharply increased. The AE monitoring system successfully recorded the process of micro-crack development and the results indicated that the risk of rock-burst could be reduced due to the appearance of calcite-cemented joint.INTRODUCTIONThe properties of jointed rocks differ considerably from that of intact rock. Due to the difficulties in specimen preparation, analogue experiments with artificially prefabricated fractures are often used to study the mechanical behavior of jointed rock (Chen et al. 2012; Kulatilake et al. 2001; Singh et al. 2001). However, natural joints are not quite similar to the artificial fractures and it is necessary to investigate the mechanical behavior of jointed rocks. Xie et al. 2011 studied the mechanical properties of marbles with natural joints by uniaxial compression tests and found that the uniaxial compressive strength of jointed rock is greatly decreased. With the unaxial compression tests, Jacobsson 2005, 2007 tested the intact and jointed granites, which were taken from the potential site for high-level radioactive waste (HLW) disposal of Sweden. However, no significant difference in strength or modulus was found. The above research results are inconsistent and it indicates the complexity of the mechanical properties of natural joints."

Jan 1, 2015

By Patrick M. - Langevin

THIS TALK IS ABOUT : How the DBL mining camp deposits have been found and what is done to find the next one PLAN: Overview of the geological context Historical exploration perspective Deposits geology and key features Conclusion

May 1, 2006

By Abhilash

Uranium is conventionally extracted using a process that employs strong acid (H2SO4) and an oxidant (MnO2) as leaching agents. This method often creates environmental problems, requires large amounts of energy, and involves a complex operational plant. It is not, however, economically attractive to extract uranium from low-grade ores by chemical leaching. Because the content of U3O8 in the Indian ore is usually below 0.1% by weight, it is necessary to develop an alternative process to enable the efficient and economic recovery of uranium. Uranium ore from the Narwapahar mines, UCIL is a type of vein deposit found in India, which accounts for ~54% in India. The ore (0.047% U3O8), though of Singhbhum area, possess exceptionally different mineralogy due to presence of some refractory minerals and richness of apatite (5%) resulting in a maximum 78% recovery through conventional processing at UCIL, with a very high consumption of sulfuric acid and pyrolusite, besides possible loss of uranium as uranium phosphate. To avoid usage of environmentally non-benign oxidants, remediation of influence of phosphates, and improve the overall process output of uranium; an alternate extraction technology using microbial isolate(s) is worthwhile exploring and the same is presented in the paper. The microbial isolate enriched with Acidithiobacillus ferrooxidans grown from source mine water was employed for bio-leaching of uranium while varying pH, pulp density (PD), particle size, etc. On varying pH at 35oC using 20%(w/v) PD and <75µm particle size, 83.5% and 78% uranium bio-recovery were observed at 1.7 and 2.0 pH in 40 days against maximum recovery of 46% and 41% metal in control experiments respectively. Whereas, it was observed that grinding of ore to finer size actually helped dissolution of uranium. Finer size particles (<45µm) gave a maximum biorecovery of 93% in 40days at 10%(w/v) PD, 1.7 pH and 35oC. The bio-recovery of uranium fell down from 93% to 82.73% and 60% on increasing the pulp density from 10% to 20% and 30% respectively for particles of <45µm size. The higher uranium dissolution during bioleaching at 1.7pH can be correlated with increase in redox potential from 433 mV to 664mV in 40 days.

Aug 1, 2010

By C. Cano

One of the main concerns within the mining industry is to minimize the impact of tailing facilities to the environment and nearby communities. Since the implementation of the first thickened tailings disposal (TTD) methodology at Kidd Creek in 1964, the thickened tailing disposal has been growing alternative disposal technology to mitigate the environmental impacts. Technical investigations on the TTD technology have been studied in detail to counteract the increasing shortage of water resources. One of the benefits observed with TTD is its resistance to potential earthquakes, particularly in zones with high seismic activity (Los Andes). TTD technology optimizes the maximum possible density for the material and generates a negative internal pore pressure in the material due to the surface and sub-surface water evaporation. This internal pore pressure should be enough to resist the pores pressure to which tailings are subject due to an earthquake action. The objective of this study is to verify the Shrinking Limit (SL) of thickened tailings during initial deposition and in the long term and the ability of tailings deposited by TTD would resist liquefaction. Fresh tailings coming from a flotation process of a copper plant concentrator were used. The samples put under cyclical three-dimensional tests associated with maximum credible earthquake magnitude range of 7.0 8.0 to develop a curve for the safety factor v/s depth for dry densities related to the maximum density obtained at the SL. At a dry density of 1.65 t/m3 liquefaction did not occur at any depth. At 90 % of dry density of 1.51 t/m3, liquefaction did not occur at earthquake magnitudes of 7.0 or 7.5 nor at any depth but liquefaction occurred at magnitude 8.0 between 0 m and 14.5 m; below 14.5 m, liquefaction does not occur.

Jan 1, 2007

By G. D. Mcdowell, L. B. Cochrane, B. D. Thompson

"Abstract - Exploration for deep underground copper and nickel sulfide deposits in the Sudbury mining camp is carried out with surface drilling. More detailed drilling, with an advanced underground exploration program, may be necessary to establish an accurate interpretation of the deposit geology and upgrade the resource estimate to the measured category for reserve estimation and feasibility assessment. Resource evaluation is a lengthy and costly process that could result in a decision not to proceed with the project. For projects that proceed to production, significant reductions in the operating and capital costs could be achieved with a more accurate interpretative model of the deposit geology and mineralization. Quality control procedures to ensure the integrity of the drilling data and interpretation guidelines are essential steps in the development of a deposit model. The use of block modeling techniques and the application of geostatistics for resource estimation further improve the quality of the resource model.Significant improvements to the interpretive models can also be achieved by incorporating additional information from geophysical measurements to validate and constrain the geological interpretation. The geophysical models must be consistent with known geological environments and oreforming processes, which has required the concurrent development of comparative models from exploited deposits. These geophysical techniques can also provide key geotechnical information required for the optimum design of the mining method and mining sequence. The objective of this program is to improve the accuracy of the deposit model and the quality of the resource and reserve estimates in order to optimize capital investments and reduce the development and operating costs of underground mining projects. Several of these techniques are currently being tested at INCO Limited’s Sudbury operations. The results from those tests are presented and their applications are discussed within the framework of resource/reserve classification systems and project evaluation objectives."

Jan 1, 1998

By Md. Rashedul Islam

Magnetic data was collected from the Yeoju historical sites using the fluxgate gradiometer through six sites & several grids. We measured the vertical gradient by the FM256 Fluxgate gradiometer. The readings were logged every half meter. The obtained data were processed and treated to introduce a high quality magnetic image. The gradiometer results defined various positive and negative magnetic anomalies, which revealed the existence of several archaeological features of different shapes and sizes. The study of the process magnetic images give us a concept that the subsurface features are caved shape stone chamber tombs, burial mounds, deep room structure, Yeoju mausoleum, pagoda?s square foundation stones, walls etc. All these are superior work of early Goguryeo inheriting orthodox Silla style. So, the study area may have great archeological interest.

May 1, 2009

By J. D. Bateman, A. S. Dadson

"The Giant claims are on the west side of Yellowknife bay about 1 ½ miles north of the settlement of Yellowknife. They were staked in 1935 by prospectors in the employ of Burwash Yellowknife Gold Mines, Limited, and were transferred to Giant Yellowknife Gold Mines, Limited, in 1937, on the incorporation of that Company. During the period 1936 to 1940 a number of surface discoveries were investigated by trenching, test pitting, and diamond drilling. A shallow inclined shaft was sunk on the Brock zone, a system of narrow and irregular quartz veins, and some 75 tons of high-grade ore was mined and shipped to the Trail smelter. In 1943 management control was acquired by Frobisher Exploration Company, Limited. An intensive campaign of diamond drilling was commenced in January 1944 and carried on continuously for 2 years. This drilling indicated the presence of substantial gold orebodies lying within well-developed shear zones. Two shafts, 1 ¼ miles apart, were sunk during 1946 and underground development started on two of the orebodies.The claims are underlain largely by rocks of the Yellowknife greenstone belt, which extends from the shore of Great Slave lake along the west side of Yell ow knife bay and northward . The most conspicuous structural features are the steeply dipping late faults. The chief of these is the West Bay, which bisects the greenstone belt at an acute angle and crosses the southern part of the Giant group. At the 'big bend' near the west boundary of the claims there is a remarkably sudden change in the strike of the fault, from about 12° N.W. to about 3° N.E. The apparent horizontal displacement along this fault is of the order of 3 miles, with the east side moved relatively north. There are also a large number of lesser faults with apparent horizontal displacements of a few feet up to l,70J feet for the Townsite fault. Most of these faults trend north to northwest. Surface examination indicates that, at least for most of them, the movement corresponds to that along the West Bay fault, that is, the east side moved relatively north. According to the available evidence, all or most•of the movem:nt along the West Bay fault and along the lesser faults was post-ore. Late diabase dyk:s that cut through ore-bearing shear zones, with chilled margins in contact with the mineralized material, are apparently displaced to the same extent as earlier geological markers. ( see Frontispiece. )"

Jan 1, 1954

By H. R. Butler, R. N. Browne

"The International Nickel Company of Canada Limited consumes some 33 ½ millions of gallons of fresh water and reuses more than 100 millions of gallons of water daily. The continuing search for suitable recycle methodology has enabled the Company to put one 25,000 TPD mill on line utilizing recycled water entirely and a second 35,000 TPD mill is under construction which will likewise employ the concept of recycled water. Future milling plans are aimed at the replacement of all fresh water with recycled water, including sewage effluent and mine waste water.WATER REUSE AT INCO’s SUDBURY MILLSAs man searches unexplored horizons for new and economic industry, he must be constantly and acutely aware of the presence or absence of that precious commodity without which Industry, indeed Man himself, could not survive -- W A T E R. The water requirements of the world today are magnanimous, considering that in 1960 the estimated consumption in the United States was over 300 billion GPD (l) or more than 1,700 GPD per person(5) The magnitude of the problem can be visualized as one considers that three times this quantity of water will be required in the United States by the year 2000, when the dependable supplies of water are estimated to be only two-thirds of that required(2). How, then can we continue to wreak such havoc on that life-sustaining substance - WATER?"

Jan 1, 1970

By C. S. Liao, S. L. Wang, C. H. Yan, F. X. Cheng

A significant development in the theory of countercurrent extraction will be presented in this article. A new term in countercurrent extraction process analysis, "Adjacent Stage Impurity Ratio" (ASIR), is proposed, and its expression is deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in the 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed.

Jan 1, 2014

By Patrick Moore

In 1971 the government of British Columbia issued a permit for the Island Copper Mine to commence disposal of 33,000 tons per day of mine tailings into Rupert Inlet, a marine fjord on the northwest coast of Vancouver Island. There was considerable controversy surrounding the development, public hearings were held, and as a requirement of the permit the company was obliged to carry out a comprehensive environmental monitoring program. The results of this program provide a thorough assessment of the environmental impact of submarine tailings disposal over the 24-year life of the mine. Following closure in December, 1995, the monitoring program continued for three years to determine the extent of marine ecosystem recovery and re-colonization. It is apparent from the findings of the monitoring program that the mine tailings were dispersed more widely than was originally predicted. It is also clear that widespread heavy metal contamination has not materialized. In retrospect it appears that submarine tailings disposal has resulted in far less severe environmental impacts than if the alternative of land disposal had been adopted. This review highlights significant aspects of public policy decision-making, design of environmental monitoring programs, and questions of interpretation of monitoring program data.

May 1, 2002

By Mike Power

Geophysical techniques have played a pivotal role in northern kimberlite exploration since the initial discovery at Point Lake in 1991. In the Slave Craton and surrounding regions, there are definite contrasts in physical properties between kimberlite intrusions and surrounding bedrock. Kimberlite commonly displays higher magnetic susceptibility, distinctive remnant magnetism, low electrical resistivity and lower density than surrounding rocks. In addition, the distinctive geometry of kimberlite pipes is reflected in geophysical responses which further facilitates target discrimination. There has been an evolution in geophysical exploration strategies over the past 12 years. Helicopter total magnetic field and electromagnetic (HEM) surveys have proven to the most cost-effective means of conducting first pass investigations in prospective areas. During the early 1990&apos;s, total magnetic field and frequency domain electromagnetic surveys were virtually the sole techniques employed during follow-up surveys. Inevitably, the initially high rates of kimberlite discovery declined in the areas surrounding the original finds. Marginal magnetic and EM anomalies were all that remained to be tested and this spurred interest in the improvement of existing interpretation algorithms and in the application of additional complementary techniques to reduce the exploration risk. Gravity has become a popular third survey following the deployment of the Falcon (TM) airborne gravity gradiometer system by BHP Billiton in 1999 and improvements in ground techniques. Ground penetrating radar (GPR) has proven to be particularly useful in delineating kimberlite pipes following drill discovery and in exploring for kimberlite dykes in settings where indicator mineral trains indicate such targets are likely. Seismic methods have been tested for both reconnaissance and delineation but remain underemployed. Given the high cost of drilling in the North and the proven success of geophysical techniques in reducing exploration risk, it is likely that an increasingly diverse range of geophysical techniques and innovative interpretation techniques will continue to be applied in kimberlite exploration.

May 1, 2003

By Wojciech Naworyta

The development of the Gubin lignite deposit, located in western Poland is the first mining investment of this magnitude in 30 years. Gubin is the second largest prospective lignite deposit in Poland, with over one billion tonnes of indicated reserves, which would be sufficient for a 2700 MW power plant for almost 50 years. The paper presents select problems related to the mining development of Gubin deposit. Attention has been paid to changes in legal and formal requirements for mining investments that were introduced after the change of Polish social and economic system. The significance of spatial, environmental and social conditionings has been emphasized. Typical attributes of the mine planning process have also been presented. Those include the long time horizon of the investment, uncertainty of external conditions and resulting difficulties in the project?s economic evaluation. Focus has been placed on mutual connections between particular elements of the project and time dependence during the process of their development. Iterative characteristics of the design process have been proven, together with resulting necessity of frequent verification of previous assumptions. As a background for presenting selected problems related to future development of Gubin lignite deposit, the methods of design have been discussed ? the variants method, the empirical method and the method of consecutive approximations. The tools and the possibilities of their use for solving specific problems related to mine design of an open pit have been broadly discussed. The chapter in which the authors relate to the specific problems of Gubin deposit development constitutes the main part of the paper. It depicts the assumptions on which the annual production and the total extraction of lignite during life-of-mine period have been based. The process of mine designing has been discussed, taking into consideration environmental, geotechnical, spatial, social and mining conditions. The criteria for choosing the location of the opening cut and the external dump have been mentioned. In the summary, the present state of mine design progress has been presented, together with some problems that will need to be solved during the next stages of the deposit?s development.

Aug 1, 2013

By Odette Corbu

The Canadian Trade Commissioner Service: Who we are ? A worldwide network of professionals in international business development, with preferred access to business knowledge and contacts, committed to advancing Canada?s interest ? Our global presence ?At home: 17 Regional Offices with over 100 trade officers ? Abroad: 149 offices in 101 countries with over 900 trade officers.

May 1, 2009

By H. Memarian

In the last few decades, many developing countries have tried to expand and improve upon higher education, which is acknowledged to be the leading factor for development. In this respect, develiping countries have significantly increased the number of tertiary institutions and their students. These rapid expansions, along with all the benefits, have drawbacks as well. An example is the status of mining engineering education in Iran. Presently, the number of active mining engineering departments in Iran (27) is more than the sum of similar departments in Canada, Australia, the United Kingdom, and South Africa (23 altogether). Also, the number of annual mining graduates in Iran (645) is more than the cumulative graduates of the United States, Canada, the United Kingdom, and Australia (613). The expansion of mining engineering education in Iran has coincided with the closing or merging of similar mining departments, as well as a decline in the number of interested students in the industrialized world. The present study shows that the need for development and the excessive number of high school graduates, resulting from high population growth in the early 1980s, are the two primary factors influencing the significant expansion of mining engineering education in Iran.

Jan 1, 2007

By V. G. Papangelakis, I. Guzman, S. J. Thorpe

Pressure oxidation (POX) leaching has been commercially applied to refractory gold ores since the 1980s. In the process, sulphide material is oxidized and dissolved in order to release the gold encapsulated in the sulphide matrix, making the gold available for further recovery. Redox potential is a significant parameter during POX, however it is only measured ex-situ at atmospheric conditions. In-situ redox potential measurement would provide instant information that allowing adjusting the process parameters accordingly. In the present study, redox potential measurements were performed during POX of sulphide material at high temperatures and high pressures. The working electrode was an Ir electrode combined with a flow-through reference electrode in a novel and robust configuration. Experiments were performed in a 2 L titanium autoclave, at 200–220°C, 50–110 psi oxygen overpressure, and 10–30% solids mass fraction. Temperature and oxygen pressure conditions were selected in order to reflect POX of refractory gold ores. Results show that the Ir electrode is consistent with theory and is able to perform well under these conditions, showing promise as a new in-situ sensor.

Jan 1, 2017

? The Mining Association of British Columbia (MABC) was established through an Act of Parliament in 1901 ? The MABC represents the interests of B.C.?s ? Coal and mineral mining companies ? Smelting companies ? Advanced stage development projects ? Key areas of work: ? Environment, Health and Safety ? Policy & Government Relations ? Knowledge and Information Services

May 1, 2008