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By Aimee Williamson

Bio-mining is a cost-effective, energy efficient and potentially environmentally protective method of exploiting a variety of ore deposits, from high-grade base metal deposits of nickel to lower-grade uranium deposits such as are found in the uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario, using bacterial metabolic processes are used to enhance the solubilization of the metal(s) of interest. The cost effectiveness of bio-mining in Elliot Lake depends on the bacterially-influenced dissolution metals of economic importance, as well as on the ability to suppress microbiological activity following the release to solution of the economically important elements. This poster provides an overview of elemental recovery results and release kinetics for more than 50 elements. The data is obtained using a combination of advanced spectroscopic tools (ICPAES and ICP-MS) to analyze solutions obtained from a series of environmentally controlled biologically mediated uranium ore extraction experiments. The focus will be on rare earth elements, potential environmentally toxic elements, and metals of economic importance. Furthermore, the importance of these findings will be put into an economic and geologic context for the re-development of the mining industry of the Elliot Lake Camp.

Aug 1, 2010

By A. Otsuki

"This paper discusses the primary collector adsorption onto a sulphide mineral in mixed collector systems to understand its adsorption mechanism. UV-vis measurements were performed to identify the primary collector concentration adsorbed on pyrite, and the adsorption kinetics under different conditions were compared to distinguish their difference between single and mixed collector systems. Small amount of secondary collector addition prior to the primary collector addition significantly improved the adsorption kinetics of primary one. The result was explained by the combination of two previously proposed mechanisms (i.e., different adsorption site mechanism and multi-layer product mechanism). This study showed UV-vis measurement as an effective tool to study mixed collector adsorption behaviour.INTRODUCTIONCollectors are surfactants composed of heteropolar molecules with a non-polar and a polar group (Lotter & Bradshaw, 2010). In a froth flotation process, the function of collector is to improve the hydrophobicity of target minerals and selectively float them with the aid of gas bubbles. Because of the chemical or physical attraction between the polar group and the mineral surfaces sites, collector molecules adsorb on the particle surface with the non-polar group assigned towards the bulk solution (i.e., water), thus the mineral particle surface becomes hydrophobic (Wills & Napier-Munn, 2006).Thiol collectors are major collectors widely used in sulphide mineral flotation. Potassium amyl xanthate (PAX), dithiocarbamate (DTC), dithiophosphate (DTP), mecaptobenzothiazole (MBT) are some common thiol collectors. Previous studies reported that some mixed collectors systems enhanced the flotation performance (e.g., Bradshaw, 1997; Bradshaw et al., 1998; Rao & Forssberg, 1997). Thiol collector mixtures are often used in the flotation of sulphide ores, and discussed with the synergistic benefits (Bradshaw et al., 1998) which include lowering the total collector dosage requirements, improving the sulphide recovery and the rate of flotation as well as the improving the froth characteristics. The current paper mainly considered the mixture between two thiol collectors (PAX and DTC, considered as a weaker and selective collector, and stronger and less selective collector, respectively (Bradshaw, 1997)) to further understand their adsorption mechanism that should assist in improving the flotation performance of refractory gold ore."

Jan 1, 2016

By C. Paulo, W. N. Wheeler, M. Kalin, M. P. Sudbury

Many researchers have tested the addition of various phosphatic materials, including Natural Phosphate Rock (NPR), to mining wastes. It was assumed that iron in the waste would form FePO4 precipitates, restricting oxygen access to pyrite surfaces and reducing oxidation. Phosphate additions were based on stoichiometry (phosphate mass to sulphide content of waste). Although some interesting, positive results were obtained with low dosages, these were considered accidental, not having followed the expected stoichiometry. In 1991, we began experimenting on tailings and waste rock with NPR, postulating that if chemo-lithotrophic microbes on the mineral surface accelerate oxidation, then heterotrophic (oxygen-consuming) microbes would reduce oxidation. All wastes with NPR produced effluents with elevated pH and low metal acidity. Later, microscopic investigations of the rocks found an organic layer on the mineral surface, which was confirmed by independent research organizations repeating experiments with very low NPR mass additions to sulphidic wastes. In 2013, heterotrophs were identified and quantified as they grew on German lignite with NPR. These data conclusively showed that the development of heterotrophic biofilms is a consequence of adding waste NPR leading to a reduction of sulphide oxidation and improved effluent from sulphidic mining wastes. We document our gradual understanding of the effects of NPR on the reduction of sulphide oxidation, covering 23 years of research.

Jan 1, 2014

By Jacques Nantel

Mechanical-electrical personnel are present in all phases of the mining industry; the coverage is broad and diversified. Concepts of energy accounting are reviewed to pinpoint the sectors with a large energy consumption. Four sectors are reviewed: underground hard-rock mines, underground soft-rock mines, open-pit mines and mineral processing. In each sector, five or six technical innovations are analyzed as to their contribution to a more efficient use of energy.

Jan 1, 1979

By A. L. Hinde, H. Dong, J. T. Kalala

"The High Pressure Grinding Roll (HPGR) is gaining acceptance in the mineral processing industry and has become a competitive technology in reducing the specific energy consumption in Mineral processing plants. The amount of samples required for HPGR amenability testwork and HPGR wear tests is usually high and often cannot be available at early stage of projects were only a few drill cores are available.Although HPGR was initiated from small scale piston die compression tests, the development of small scale piston die test to predict the performance of HPGR has been slow.The objectives of this paper was to present the designs, operating procedure of piston-die press and operating conditions which have resulted in similar particle size distribution obtained from a piston die test and HPGR Labwal unit starting from the same feed size distribution. Testwork were conducted using a 2 MN piston-die press and a Labwal HPGR unit on major South African ore types, viz, gold, platinum and iron ores. The results obtained show that piston-die test can generate data to predict energy consumption, product size distribution, and even to evaluate the edge effect."

Jan 1, 2012

By P. Chu, J. A. Finch, R. Li

"Bubble size plays a key role in flotation. In this paper, we examine the possibility of using passive acoustic sending to determine bubble size. Software was developed based on Short Time Fourier Transformation (STFT) to analyze the frequency of the acoustic signal emitted from the bubble formation event. Bubble size was determined from the Minnaert frequency. The acoustic-determined bubble size responded to reagent dosage, but was less sensitive than that given by imaging. The constraints of the current acoustic approach are discussed.INTRODUCTIONBubble size is an important factor affecting flotation performance. It determines the maximum available surface area for collecting and transporting mineral particles. Of interest for process control (Gorain, Franzidis, & Manlapig, 1995), it can be determined by several techniques, such as image analysis (Grau & Heiskanen, 2002; Hernandez-Aguilar, Gomez, & Finch, 2002); conductivity (Barigou & Greaves, 1992); drift flux analysis using gas rate and gas holdup measurements (Banisi & Finch, 1994); and optical sensors (Randall, Goodall, Fairlamb, Dold, & Connor, 1989). However, all these techniques have drawbacks.Acoustic analysis of the oscillatory behaviour of bubbles to extract bubble size is another possibility (Leighton & Walton, 1987; Pandit, Varley, Thorpe, & Davidson, 1992; Al-Masry, Ali, & Aqeel, 2005; Manasseh & Ooi, 2009; Leighton & White, 2012; Spencer et al., 2012). The fundamental basis is the work of Minnaert (1933) who first correlated the bubble size with its natural frequency, Equation 1:"

Jan 1, 2016

By L. Byszynski

The results of a three month evaluation of the application of EMEW® technology at the KGHM Glogów II Smelter tank house bleed stream are presented. The current, conven¬tional electrolyte decopperization process has some limitations, including: only a fraction of its production is commercial grade cathode copper, significant operating costs, low current efficiency, low current densities resulting in low copper depletion rate, and arsine gas and sulphuric acid emission. The EMEW® cell technology developed by Electrometals Technologies Ltd. can overcome many of these limitations. Tests were performed on a pilot EMEW® installation comprising 30 cells at ambient temperature on electrolyte bleed, using current densities between 100 and 600 A/m2 , with copper concentrations between 45 and <1g/dm3. Results showed that a high grade copper can be obtained to the level of 7 g/dm3 of copper concentration in electrolyte. The use of EMEW® technology allows the direct and efficient recovery of over 85% of the copper contained in the bleed electrolyte. Glue & thiourea addition were tested in order to improve the parameters of the copper depletion process. The behavior of Arsenic and Bismuth was observed and a means for their elimination from the system proposed. On-line copper concentration monitoring is proposed to improve control and performance.

Jan 1, 2007

By D. A. Brown, C. Lowe

"Abstract -A multi-sensor (electromagnetics, magnetics, gamma-ray spectrometry, and VLF) geophysical survey was recently conducted in the Purcell Basin of southeastern British Columbia in an area encompassing the world-class Sullivan Sedex deposit. The purpose of the survey was to geophysically characterize the known mineral occurrences and to develop strategies to enhance future mineral exploration in the basin. Follow-up investigations of geology and measurements of rock physical properties helped constrain interpretations of the geophysical data sets.Despite extraction of more than 90% of the ore from the Sullivan deposit, it is clear that the mineralization there, as well as at other Sedex occurrences surveyed, is characterized by high conductivity values, strong bedrock conductors, and elevated magnetic anomaly values. The albite-sericite alteration which accompanies this mineralization yields high potassium and low thorium-potassium ratio values. Associated Moyie gabbro is characterized by low electrical conductivity and radioelement concentrations and by high magnetic anomaly values. The study has also aided exploration for other mineral deposit types including stratabound Cu-Ag, placer gold, vein and disseminated basemetal deposits. In addition, the geophysical data have helped constrain geological interpretations of the basin."

Jan 1, 1998

By P. van Zyl, M. Lombaard

The 14MW SAG mill at Tarkwa, Ghana, experienced a frozen drop charge incident on 10 February 2010. This caused downtime of 112 hours, a repair cost of $200k and production loss of 162,000 tons, corresponding to a loss of $8.9M. A new locked charge protection system was installed on the two Tarkwa mills on 30 July 2010, mitigating this risk. This system calculates the ore angle in real time while the mill is starting up and trips the mill if the ore angle exceeds a trip angle setting. The calculation of the ore angle is derived from the mill motor rotor currents only - no mechanical transducers are required. The head of Gold Fields West Africa, Peter Turner, says of the new system: "This is excellent work and the type of technology that has had and will continue to have, major opportunity cost impacts on our business."

Jan 1, 2012

By C. B. Ndimande, C. Ntsele, M. Lisso, L. Arlow

"In the processing of UG2 platinum ore, stirred milling technologies are dominating regrind applications that require grinding the particles to P80s’ in the region of 45 µm. For this application stirred mills are 30–40% more energy efficient and require a smaller foot print compared to traditional tumbling mills. In this work a study was carried out using a batch pin mill and three scales of Stirred Media Detritors. A laboratory scale pin mill, a pilot scale Stirred Media Detritor with an installed power of 18.5 KW and two industrial scale Stirred Media Detritors in continuous operation, with an installed power of 355 KW and 1,100 KW were used. The industrial scale SMDs were in the secondary grinding section of a mill floatmill float (MF2) UG2 processing plants. The tests were focused on assessing the effect of feed rate and percent solids on power consumption and product fineness at lab scale, floatation response of the SMD product at pilot scale and on an industrial scale, the effect of feed rate on energy consumption and product fineness. The measurements obtained were feed flow rates, mill power and from the samples cut, particle size distribution of both feed and product. Specific energy was observed to increase with increasing percent solids over the 30wt% to 80wt% studied. Floatation response tests of the pilot scale SMD products show improvement in grade. Specific energy and reduction rations are observed to decrease with an increase in feed rate.INTRODUCTIONThe purpose of comminution in most mineral processing applications is to liberate the valuable minerals from gangue so that they can be recovered in subsequent separation stages. Most precious and base metal plants treat low grade fine-grained ores which require a higher degree of size reduction to yield the necessary degree of liberation (Partyka & Yan, 2007). Many authors have shown that the relationship between product size and grinding energy consumption is exponential, the finer the product from the comminution device, the higher the energy consumption (Gao & Weller 1993; Napier-Munn, Morell, Morrison & Kojovic, 1996; Jankovic, Valery & La Rosa, 2003). The suggested reason for this kind of relationship is that smaller particles have fewer flaws and higher strength than larger particles. Particles with fewer flaws and higher strength require higher energy for breakage to occur. One of the challenges most plants face is that of efficient energy utilisation in the liberation of the mineral from these complex ores. Conventional tumbling mills are not energy efficient in fine and ultra-fine grinding applications because some of the energy is spent on moving the charge and does not go directly into breakage. Stirred mills have been found to be about 30% to 40% more efficient and require a smaller foot print compared to traditional tumbling mills for regrind applications that require product size with P80s’ in the sub 45 µm regions (Radziszewski & Allen, 2013). Stirred mills are able to produce fine product because they can achieve a high number of stress events per unit time and volume compared to tumbling mills (Kwade, 1999a). To minimise energy usage without compromising product quality, the mining industry has adopted stirred milling technologies for fine and ultra-fine grinding (Radziszewski & Allen 2014; Kwade, 1999b). The south Africa platinum group metal (PGM) industry alone had over 40 stirred media mills installed by 2011 (Rule, 2011). Of that 40, 13 were in the ultra-fine grinding (UFG) application and the rest in main stream inert grinding (MIG)."

Jan 1, 2016

By D. L. Marchioni

"The detection and quantification of the degree of weathering is an important aspect of coal exploration and mining. Tests for weathering which are suitable for the exploration camp should be fast, simple, and require minimal equipment and operator expertise. In this study, two tests which fulfill these requirements were evaluated using samples of Western Canadian coals. These tests, one based on the pH of a coal slurry and the other on the flotation of coal in a water/diesel oil mixture, do not appear to give consistent results and are not recommended as ideal weathering parameters.IntroductionThe weathering of coal results in a deterioration of those properties which render it suitable for use in industrial processes. Consequently, the detection and quantification of the degree of weathering is an important aspect of exploration and mining. Frequently, decisions related to the depth of the weathered zone must be made at the exploration camp and, therefore, tests for weathering which are fast, and require relatively inexpensive and portable equipment and minimal operator experience, would be very useful. The aim of the study reported here was to evaluate two tests used by U. S. Steel Corp. to detect coal weathering and which satisfy the requirements for use in an exploration camp. The study is a continuation of a more extensive examination of the detection of coal weathering by various methods, reported elsewhere (Marchioni, in press)."

Jan 1, 1981

Presentation Overview ?WRDC Purpose and Activities ?Women in Trades, Technology and Operations (TTO) Occupations ?Factors in Successful Recruitment / Retention of women (VBNC) ?Recruitment and Retention Strategies ?Conclusion Women in Resource Development Committee (WRDC) ?Incorporated in 1999 as a Not for Profit Organization ?Based in Newfoundland and Labrador ?Works to Increase the Participation of Women in Natural Resource Industries ?Research (Using Gender-Based Analysis) ?Career Exploration Programs for Women and Girls ?Outreach and Advocacy ?Policy Development ?Public Awareness and Education ?Gender Sensitivity Training ?WRDC Educational Resource Centre

May 1, 2006

By L. A. Wolff

"Second only to profitability (but not always), productivity is the most sought after measurement for any operation. Whether it is in mining, manufacturing, construction, etc. managers always strive to know how productive various plants are. Even the Federal Government publishes, on a monthly basis, the nation&apos;s factory productivity.Just what is productivity and how is it measured? This is an important topic that needs definition. There could be as many definitions as there are people who use it. In the mining industry, the problems of defining productivity would be analogous to the definition of equipment availability. Each mine uses its own definition to suit its needs. Webster&apos;s Dictionary primary definition for productivity is ""the quality or state of being productive,"" with productive defined as ""yielding or furnishing results"". This is a definition open to a broad spectrum of interpretation. A discussion of how productivity is currently used in the mining industry and an introduction to a potentially different approach to its measurement and meaning is outlined in this paper.Defining ProductivityTypically, mining companies track several productivity measurements. These are partial measurements and can include the following: tons per specific equipment class per hour, tons per man-hour, and tons per shift. None of these, however, track the over -all performance of an operation, that is, a unit of output per unit of input.For a mining operation, output can be defined as the ore for mill processing. Input includes the required components of production to get to the first step of processing.The Wesbter&apos;s Dictionary definition exposes a major fault with the popular conception of productivity. The critical issue of accountability is not addressed. Anyone can produce, but how effectively and efficiently are resources used? Quantifying an inclusive measurement is difficult. Statistics referring to an increase in productivity are often published. For example, the statement, ""gold productivity has increased by 10%"" has many potentially dangerous interpretations. One must ask, what does this statistic really mean? Did gold companies produce 10%” more gold? Were less manpower or equipment required to produce an equivalent amount of gold? Did ore grades increase resulting in more ounces of gold produced, etc. Obviously, production and productivity can have similar implied applications and meanings, but also two different, distinct meanings.To mitigate a problem like this, a standard needs to be developed within the mining industry. Because of varying ore grade, changing waste to ore ratios, different mining methods, etc. all of which have a direct impact on mining, development of a standard is difficult. Kendrick(1) discusses the use of Total Factor Productivity as a productivity measurement. Summarized, the total factor productivity measure is an indication of the change in efficiency in the use of basic labour and capital factors associated with an operation.This measurement has little meaning when calculated at a given point in time. It should be an on-going calculation, tracking an operation over a period of time, to evaluate trends. These trends can be used to determine if an operation&apos;s productivity is what it should be, and alert management to potential problems before they become major and adversely affect an operation."

Jan 1, 1990

By A. Mcdonald

"An X-Met Analyzer was purchased from Outokumpu in late 1983for use in the Hudson Bay Mining and Smelting smelter. Its first use was in the fuming plant to give zinc assays of each charge of slag tapped from the fuming furnaces. This quickly told the operators exactly when each charge had reached its economic tap-out point, and gave supervision a fool-proof method of identifying good operation. These and other factors led to major improvements in coal utilization in the fumers and to major increases in zinc oxide production. A second unit was later purchased for the reverberatory furnace to give silica and iron assays of the slag, and these were used to make adjustments in the feed composition to maintain the desired SiO2:Fe ratio in the slag. Since purchasing the units for the furnace, the oil consumption and copper content of the slag have dropped significantly. IntroductionSmelters have lagged far behind concentrators in process control by mean s of rapid product analysis. The on-stream X-ray analyzer was developed about seventeen years ago, and soon concentrators around the world were getting assays of the incoming ore, .concentrates and tailings every fifteen minutes, and using these to control reagent additions and other process variables. Almost always, the concentrate grade and recovery improved.In smelters, product streams are solids or molten materials, not the more easily handled slurries, and until seven years ago no inexpensive equipment was available to provide rapid analysis of this type of material. In approximately 1980, several companies developed instruments based on irradiating solid samples with low-intensity gamma rays from radio-isotope sources, and measuring the secondary X-rays emitted from different elements in the sample to provide an analysis of the elements desired.The smelter staff had a close look at what was needed and listed the following points as being critical:1. ability to provide Zn assays of a sample of slag within 15 minutes of taking it, in order to achieve optimum fuming times (zinc fuming , being a batch process, had the greatest potential benefit from rapid slag analysis);2. ability to give Cu and Fe assays on the slag, and on other smelter products, such as matte and converter slag;3. ability to give Si02 assays since the SiO2 content of the slag has a strong effect on fuming rate; and4. ability to stand up to an industrial atmosphere such as exists in the fuming plant."

Jan 1, 1987

By G. Ladouceur

"Northgate Patino Mines produces a copper concentrate assaying 22% Cu. Moisture content of the product averages 12.5% H20 when dewatering with conventional vacuum disk filters. Recent smelter contracts reflect higher energy costs and increased moisutre penalty charges. This situation forced Northgate to investigate possible alternatives such as rotary dryers and pressure filtration. After laboratory testing, it was found that pressure filtration could economically meet the smelter&apos;s requirements. Pilot plant testing was then undertaken and confirmed the laboratory test results. Based on these findings, a model I.S.F. 1500 x 28/22 I.R. Lasta filter press was purchased.This paper describes the Copper Rand dewatering flowsheet the operation of the press and the economics of the process.IntroductionNorthgate Patino Inc. operates 2 und erground copper mines and a 3300 ton per day concentrator located in Chibougamau, Quebec, some 425 miles north of Montreal and 300 miles northeast of Noranda, Quebec.Copper concentrate is produced at a rate of 250 tons per day and trucked to a C.N. siding 10 miles from the mill site and then railed to the Noranda Smelter.Until early 1981, moisture content of the concentrate at 12.5070 was acceptable since smelter penalty charges were relatively low ($0.10 per ton per unit over 10070 moisutre). In January 1981, a new contract was signed in which the penalty was raised to $1.10 per ton per unit over 8070 . This and the increasing truck and rail costs justified the change-over from vacuum to pressure filtration . The Lasta I.S .F. 1500 x 28/22 was then purchased and installed, and operation of the plant started in December 1981."

Jan 1, 1987

By Bob Rappolt

Discussion Points Part 1: Global Mining Industry/Related Issues ? Historical Metal Price Trends. ? Historical LME Metal Stockpiles. ? China?s Demand for Metal. ? World Population Growth, Demands and Development. Discussion Points (cont?d) Part 2: Canadian Mining Industry ? Where are we? And where are we going? ? What progress have we made in the past 20 years regarding: ? Safety -Employee Levels ? Labour -Relative Compensation ? Productivity - Technological Advance ? Where do we stand regarding mineral production? ? What does the future hold for us?

Apr 1, 2005

By F. W. Wellmer

"This paper discusses the changing nature of reserve/consumption ratios, using data from Canadian operations and focussing particularly on copper.IntroductionStudies in world metal consumption and world metal reserves are done regularly by the U.S. Bureau of Mines, the German Federal Institute of Geosciences and Raw Materials, and other institutions. Formerly, on the basis of these data, the following figures were calculated:• a static lifetime of reserves-reserves at year end divided by the consumption of the previous year;• a semidynamic lifetime of reserves-reserves at year assumed constant growth rate.These figures were severely criticized because they were purely theoretical and did not consider the availability of the raw materials.Recent practice is to calculate reserve/consumption ratios (R/C ratios) for periods(1) or for different years(2,3) and to interpret the trend. For base metals, these R/C ratios are increasing (Table 1). This had led to the conclusion that today the relative availability of base metal reserves has increased as compared to 10 or 15 years ago(4,5) As there are normally numerous deposits for each commodity, the anticipated production rates of deposits are irrelevant to this conclusion as long as the statistical distribution of possible production rates does not change significantly.The above conclusion is only justified if the quality and the nature of the data base remain the same. This is certainly the case for the consumption data. It is also assumed for the quality of the reserve figures, which usually take into account only proven and probable reserves. For the nature of the reserve figures, however, this does not seem to be true.Undoubtedly, the reserves increased in absolute terms between 1966 and 1978. To put the absolute reserve figures into perspective, it is common, as said above, to compare them with the mine production, which increased in the free world between 1966 and 1978; e.g. for copper by 40%, for Pb by 17% and for zinc by 36%. However, the reserves are also influenced by other factors, such as average size of the mines, changes in the grade of the mined ore, price-to-cost relationships and the like.The purpose of this paper is to examine the nature of the reserve figures in more detail. Because the completeness of mining data published in Canada is rather exceptional, Canadian .data serve as an example and it is assumed that the conclusions can be extrapolated to other mining countries or at least to those with free market systems."

Jan 1, 1981

By Rod Maclean, George Stewart

"This paper covers the planning, development, and mining of an underground pillar complex using a bulk mining method. To achieve the long-term goal of continually improving our operating processes, all cut-and-fill and undercut-and-fill workplaces at Thompson Mine have been evaluated for their conversion potential to the bulk method referred to as VerticalBlock Mining (V.B.M.).Since December 1979, conversion has occurred to the extent where 80% of the ore hoisted is mined using Vertical Block Mining (V.B.M.).Productivity and profitability have been substantially improved by converting to this bulk method, especially in pillar areas.IntroductionThompson Mine is a 6000 ton per day underground nickel mine located 3 miles outside the City of Thompson, 400 air miles north of Winnipeg . The mine has two shafts, T-l and T-3 (Fig. 1). The T-l shaft is 4427 feet deep with the deepest mining taking place on 4000 level. The T-3 shaft, which is the area of this presentation, extends to a depth of 2607 ft with the deepest operating level at 2400 ft. The two shafts, some 10 000 ft apart, are connected underground on numerous levels. The ore mined at T-3 is trammed on 2400 level to the T-I main ore pass and hoisted through the T-l shaft. Eight hundred and fifty thousand cubic feet of fresh air per minute ventilates the mine.The 1400 level 310 pillar complex is located in the T-3 mine area. There are six rib pillars, two crown pillars and one main pillar (boundary pillar between cut-and-fill stopes) within the complex (Fig. 2). The majority of the ore in this area has been mined using mechanized cut-and-fill techniques .Undercut-and-fill mining was the method originally planned to recover these pillars. It is slow, labour-intensive, and requires extensive use of timber during the mining cycle. The extraction drifts in the area are heavily timbered due to their proximity to the ore and the age of the facilities. Increasing drift maintenance costs and the successful mining of two main pillars with V.8.M. techniques provided the stimulus to review the mining plans for this area."

Jan 1, 1988

By Simon Hanner

November 2005 Memorial University Newfoundland and Labrador Mines and Energy Review of Activities Exploration and Mining New Brunswick ?Université du Québec a Montréal McGill University 2005 Manitoba Mining and Minerals Convention Université Laval Quebec Exploration 2005 Saskatchewan Open House December 2005 University of Calgary University of Alberta &apos;Laurentian University &apos;Queen&apos;s University &apos;University of Toronto &apos;Ontario Prospectors Association January 2006 Mineral Exploration Roundup, BC March 2006 Prospectors and Developers Association of Canada Convention April 2006 University of Ottawa Carleton University

May 1, 2006

By T. S. Wanne

Tunnel sealing experiment (TSX) was conducted between 1997 and 2004 in the Canadian URL located in Manitoba. In the experiment, a tunnel was excavated parallel to the maximum principal stress direction, filled with sand and sealed with bulkheads at both ends. It was then pressurized and heated by injecting hot water. The rock mass response was monitored with seismic methods. The main interest in the numerical simulation was the damage formed during the heating phase. The large-scale PFC2D models replicated a central plane- strain section of the TSX chamber. The models captured the first-order phenomena observed in-situ displaying the difference in the damage in the roof and floor regions, respectively. This difference was due to the filling material confinement of about 100 kPa on the tunnel floor, which occurred in the course of the heated experiment.

May 1, 2009