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By B. Morrison

"The Kiruna Electric System is a recently developed inclined ore haul age system for underground mining operations. Although an initial investigation was carried out at the Swedish underground iron ore mine LKAB almost three decades ago, it was not until 1981 that the resources of LKAB, ASEA and Kiruna Truck AB were combined to investigate, and subsequently develop an ""all- electric truck"" for the mining industry.It has long been appreciated, that major economical advantages could be realized by a mining operation through an extension of the cost-effective life of the existing ore hoisting system by the use of ramps to haul ore up to the main haulage level. Diesel truck s have been used and are being used for ramp haulage. Their use however, is limited due to ventilation and operating costs restraints.There are numerous instances of orebodies, located within a couple of hundred metre s of surface, or below an existing hoisting facility, being developed by ramp access while the shaft is being sunk. Development of an orebody via ramp access has many advantages to a mining operation where mechanized mining is to be practiced. These advantages are both practical and economical; generally falling within the over-all umbrella of the phrase ""cash flow"" mining.The decision to sink a shaft is a major committment by any mining company, regardless of size and financial reserves. Extensive diamond drilling, both shallow and deep must be carried out before a decision can be executed. This constitutes a major financial expenditure over an extended period of time.The decision to sink a shaft must be weighed against the reliability of geological interpretation of the deep diamond drilling results, the stability of the mineral market and potential fluctuation in ore prices and interest rates."

Jan 1, 1989

By J. C. Kurnia

Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers? pneumoconiosis and silicosis. Major sources of dust appear of course along the mining face where the minerals are extracted. Proper control and management are required to ensure safe working environment in the mine. Presented here is the use of a computational fluid dynamic (CFD) approach to investigate the flow and dust behaviour in mining tunnels. The objective of this study is to propose and examine various strategies to mitigate dust dispersion from the mining face and reduce dust concentration to a safe level for the operator. In a companion study, the authors investigated various methods for mitigating dust dispersion from the mining face to ensure safe dust concentration levels in the mine tunnel. Among the examined methods, implementation of brattice to direct the flow from the main airway to the mining face is the most effective method to disperse dust particles away from the mining face. The installation of brattice, however, will limit the movement of mine operators and vehicles in the tunnel. Hence, application of a hybrid brattice which is a combination of a physical brattice along with suitable directed and located air curtains is proposed and examined. Based on the CFD simulation results, over a range of parameters of interest, it was found that the physical brattice blocks the ventilation air and directs it to the mine face while an air curtain located along the brattice outlet offers flexibility in keeping the dust away from the operator allowing more freedom for the operator and the equipment. Results of the modelling over a range of parameters of interest are presented and discussed with the goal of managing dust concentrations within safe limits for the operator.

Aug 1, 2013

By D. H. Whiting, A. J. Sinclair

"The San Antonio gold mine, in the Archean Rice Lake Greenstone Belt, was in continuous production from 1932 to 1968, during which period the mine yielded 1.35 million ounces (41 985 kg) of gold and 195,000 ounces (6065 kg) of silver from 4.88 million tons (4.44 Mt) of ore for average grades of 0.28 ounces per ton (9.0 g/t) gold and 0.04 ounces per ton (1.3 g/t) silver. After the 1968 closure, several publications appeared implying that gold grade of ore decreased with increasing depth.Recent observations by the authors show that the relatively low grades in the middle levels of the mine are controlled geologically. However, the reduced average are grade in the lower levels of the mine was due to inadequate mining control that led to a high level of dilution. The similarity of geological factors such as vein styles within structural domains, variations in mining control, recent ore muck sampling results and lithogeo chemical profiles all indicate the similarity of ore in both upper and lower levels.Strict mining control should yield improved grades of gold for future production from the lower levels at San Antonio, in contrast with the production grades of the late 19605that represented extensively diluted ore. High-quality production records are an essential component in re-evaluating a past producer, particularly where workings are accessible. Poorly founded conclusions which cannot be checked by access to workings can have a negative impact on the evaluation procedure."

Jan 1, 1990

By J. F. Henderson

Stable mining operations commenced in the Northwest Territories in 1933. Pitchblende from Great Bear lake and gold from the Yellowknife district are the main minerals produced. The value of pitchblende products produced from 1933 to 1941 was nearly $6; 000; 000; data on subsequent production are not available. The first gold was produced from the Con mine at Yellowknife in 1938. Other properties that later came into production include the Negus; Slave Lake; Thompson Lundmark; and Ptarmigan mines. The annual gold production reached $3; 862; 000 in 1942 but due to the war and consequent labour shortage fell to $333; 218 in 1945. The only producing mines at present (May; 1947) are the Con and Negus; but several promising properties are under development; including that of Giant Yellowknife Gold Mines where large tonnages of ore are being blocked out. With the reopening of former producing mines and new production from properties now being developed; gold production should rapidly increase and exceed its former peak within the next few years.

Jan 1, 1954

By T. T. Wang, T. H. Huang, S. S. Zhan

"Fractures with diverse features dominate the hydraulic behavior of fractured rocks and are one of the major subjects for hydrogeological characterization of a site. This study investigates curve patterns obtained by packed tests, and as well the influence of fracture features based on 59 sets of in situ packer tests with different fracture combinations and fracture features. The result shows that, in the example of Heshe site, neat and tidy fractures usually provide stable channel for water flow during testing, and the hydraulic properties of fractures infilled with breccia and mud may change during testing because of leaching and/or washed out of infilling breccia and mud. Different combinations of fractures with diverse features in packed test sections lead to different curve patterns for in situ hydrogeological tests. For groundwater flowing predominately through neat and tidy fractures, the pressure-discharge curve of modified Lugeon tests are usually linear curve pattern, and the pressure decrease while the discharge increase in pressure-discharge-time curves of single-hole double packer tests, which benefit statistically determining the transmissivity of dominant fracture sets. INTRODUCTIONFractures interlaced in rock masses are major channels for groundwater flow and generally account for the anisotropic and heterogeneous characteristics of permeability for fracture rocks. To describe reasonably the permeability of a fracture rock, the Discrete Fracture Network (DFN) approach and others with similar ideals have been developed. Many methodologies and associate equipment, for instance, the televiewer and the in situ hydrogeological test, have been proposed to investigate the spatial distribution and the transmissivity for different fracture sets, which are two main parameters necessary for the DFN or similar model simulation (Pearson & Money, 1977; Barker & Black, 1983; Hsieh et al., 1985; Bernard et al., 2006; Quinn et al., 2012). However, diverse outlooks for the pressure-discharge curves and the temporal pressure and associate temporal discharge curves often confuse the investigation results by significant deviations on derived permeability (Houlsby, 1976; Zlotnik, 1994; Royle, 2009; Camilo, 2010).Aiming on technical development for in situ hydrogeological tests and fracture investigation, an experimental well site with 10 wells has been established in Heshe in central Taiwan since 2011 (Wang et al., 2011; Song, 2012; Zhan et al., 2013). Extensive geological survey and well-hole scanning by a televiewer provide spatial distributions and outlooks of fractures in detail. Additionally, a series of Lugeon tests, double packer injection tests and pumping tests have been performed to investigate the permeability of fracture rocks, and dominate fracture sets as well. Based on the results obtained from the Heshe site, this study classifies the curve patterns of hydraulic packer tests. The features of fractures involved in packed sections for packer tests are then inspected in detail. Relationship between the curve patterns of hydraulic packer tests and associated features of corresponding fractures in rock are discussed and addressed accordingly."

Jan 1, 2015

By T. S. Smith, C. C. Rennie

"THE LEAD-ZINC and tungsten mines of Canadian Exploration Ltd are on Iron Mountain, 8 miles south of Salmo, B.C., in the Nelson mining division. Relative location of the mines is shown on the general plan.First recorded lead production was in 1908 from surface outcrops. Small amounts of high lead ore were mined intermittently until 1926. No major lead-zinc production occurred until 1949 when outcroppings on the south side of the mountain were mined and diamond drilling began to prove the existence of a large replacement orebody. Lead-zinc ore has been mined continuously from the Jersey orebodies since March 1949, with monthly tonnage as high as 50,000 tons per month, but currently averaging 30,000 tons per month.Schee1ite-bearing tungsten ore was found in 1942 by H. Lakes in an old adit and open cuts at the north end of the Emerald tungsten orebody. The Emerald tungsten mine was developed by the Federal Government as a Wartime Metals project and operated for eight weeks in the fall of 1943, when the poor demand for tungsten closed the mine. Canadian Exploration Ltd. purchased the mine in 1947 and mined in excess of 100,000 tons in 1947-48 until the demand for tungsten dropped again and interest was centred on lead-zinc. The Federal Government repurchased and reopened the Emerald Mine in 195 L and built a new concentrator. The mine and mill were sold back to Canadian Exploration Ltd. in 1952.Regional Geology and IntrusivesThe host rock for both the lead-zinc and tungsten mineralization is the Laib formation of Lower Cambrian age, which consists of 400 feet of crystalline limestone underlain by beds of argillite, and argillaceous limestone locally altered to ""skarn"" or ""tactite"". The Laib limestone is overlain by black argillite and underlain by the Reno quartzite of Pre- cambrian age. Repetition of folded beds has allowed the interpretation of the large isoclinal fold which repeats the limestone (see general cross-section). Dolomitization and the associated lead-zinc ore have been found only in the right-side-up limestone and are not known in the overturned limestone.Two elongated stocks of granite cut the sediments. The Emerald stock outcrops along the east side of the Emerald tungsten mine and again west of the Jersey workings, while the Dodger stock outcrops only at the north end of the Iron Mountain. The shape and attitude of these bodies are believed to have been governed partly by pre-granite faulting and partly by pre-granite folding of the sediments. Although some forceful intrusion may have occurred the detailed granite surface indicates a gentle stoping emplacement."

Jan 1, 1949

By Larry T. Yano, Gerald T. Handford

"Tailings Engineering has the responsibility for planning and coordinating tailings disposal and for ensuring the stability of the tailings dyke. The inclusion of both the planning and geotechnical functions in one team has resulted in greater efficiency in the design and planning process. Major challenges in tailings disposal facing Syncrude are in the areas of: (1) sludge disposal; (2) instrumentation and monitoring; and (3) liquefaction. Meeting these challenges will have a significant effect on the cost effectiveness and reliability of the mining operation.IntroductionThe size of the tailings disposal operation has led to the establishment of a large engineering team devoted solely to the disposal of tailings. This paper discusses: the tailings disposal operation, the role of tailings engineering, the organization, inter faces, and the present and future challenges with respect to tailings disposal."

Jan 1, 1990

By W. G. Spencer, E. Sulis, P. M. Tiley

"Dome Mine's No.8 shaft is located about 1 km northeast of Dome's No.3 shaft and mill complex in South Porcupine, Ontario.No.8 shaft was brought into production in 1984 to hoist ore and waste for the complete mine as well as to service the mine from the 1600 level and below. Access above 1600 level is provided by No. 3 shaft.The rectangular shaft has six compartments consisting of two skips, a cage, counterweight, manway, and a service compartment. The over-all size of the shaft is 14 ft 7 in. by 20 ft by 7 in. (Fig. 1). A 7th compartment for shaft deepening is incorporated in the bottom 500 ft of shaft. The shaft is 5470 ft deep. The loading pocket is located at 5300 ft and the dump 61 ft below the collar.Surface facilities consist of a concrete headframe and a structural steel hoistroom which houses the cage and production hoists . The service hoist is a 12-ft diameter double drum, with one 1750 HP DC motor, and the production hoist is a 15-ft diameter double drum with twin 1750 HP DC motors.Both hoists have a single clutch and a single reduction gear train built by Orenstein & Koppel, and equipped with Canadian General Electric drives. The cage hoist is equipped with a disc pinion brake.The skips were originally aluminum 14-ton capacity, Rolla-chute design with steel liners on three sides and 4 in. of rubber on the back, to absorb the loading impact. The original guide rollers consisted of fixed 10 in. pneumatic tires. The face-to-face units were eventually replaced with larger airplane-type tires mounted on a spring loaded pivot arm."

Jan 1, 1993

By G. M. Ritcey, M. Silver

"The processing of uranium ores produces tailings that could constitute environmental problems. At most operations the tailings are dumped into a designated area, with the ultimate acid drainage occurring if sulphides are present, together with the release of metal constituents to the rivers and streams. If the chemical reactions occurring within the tailings could be predicted, perhaps methods could be developed to either increase or decrease 'the rates of reaction. One such study has been in progress at CANMET during the past three years. The paper describes the use of Iysimeters containing low-grade and complex uranium tailings to determine the effects and interactions of bacteria, sulphides and solvent extraction organics on the release of radionuclides and on acid production. A simulated rain cycle nine-fold the normal was used and the Iysimeters were subjected to timed intervals of light and darkness. As a result, the tests simulated a 25-year period.IntroductionAlthough Canadians derive major benefits from uranium, there are environmental and health consequences, not yet fully understood, from the associated mining and milling operations. A major project at CANMET (Canada Centre for Mineral and Energ y Technology) has the ultimate goal of ensuring that any adverse effects on man and environment, now or in the future, resulting from the processing of uranium should be acceptably low. The magnitude of the task was exacerbated by the fact that the increased demand for electrical energy and the resultant increased prices for uranium oxide during the 1970s led to a rapid expansion in the industry. Annual world demand for uranium was expected to increase 12-15 fold in the next quarter century, with annual requirements of between 200,000 and 300,000 metric tonnes anticipated by the year 2000. Currently, the demand is low and the prices for the oxide have decreased."

Jan 1, 1982

By I. H. Warren

"An analysis of form-coking processes is presented in terms-of their fundamental mode of operation and their relationship to other coking processes. Their possible future role in cokemaking is assessed. IntroductionAny consideration of prospects and possibilities for form coking must commence with the iron and steel industries-their likely future growth pattern on a world and regional basis and the potential direction of future developments in iron and steelmaking technology.From the numerous estimates which have been made of the future consumption of steel, it would appear that a growth rate of 3lllo between now and the year 2000 is likely. Radical changes in steel making technology are unlikely to be commercially adopted on any significant scale during the next twenty years . However, widespread commercialization inter alia of continuous casting and direct reduction, growth of electric furnace steelmaking and a decrease in coke rates will all contribute to a growth rate for metallurgical coke that certainly will be less than that of steel."

Jan 1, 1980

By Kevin J. Melong

"Redpath Canada Limited and joint venture partner Thyssen Mining and Construction Canada have recently completed the sinking of the Scissors Creek service in Saskatchewan through its joint owned company, Associated Mining Construction (AMC). The Scissors Creek service shaft was sunk at Nutrien’s Rocanville mine. The following paper outlines the shaft sinking plant and the methodology related to sinking and shaft lining. KEYWORDS Hydraulic shaft jumbo, Hydraulic shaft mucker, Potash shaft sinking, Shaft lining, Sinking galloway INTRODUCTION The sinking and lining of shafts at mines to access mineral deposits has always been one of the great mining challenges for owners, engineers and contractors. Over the course of history in Canadian mining, the sinking of potash shafts through the notorious Blairmore formation of Saskatchewan has proved to be some of the most challenging shaft sinking projects on record. There is no doubt that today’s shaft sinking business demands the utmost in safety performance while delivering projects within schedule and budget. Given these requisites, Redpath and TMCC (executed under the joint venture company, Associated Mining Construction or AMC), were taxed with developing the shaft sinking system to deliver this program in the safest and cost effective manner, with due regard to schedule and quality. Traditionally the potash shafts sunk in Saskatchewan involved a significant level of manual labour, owing to the methodology of excavation by means of chipping the frozen shaft sections with hand held pneumatic machines, and manually placing tubbing segments or steel liners of the shaft lining system. Most certainly, the AMC team wanted to make a step change from those earlier sinking programs and develop systems for sinking this potash shaft that removed the high level of manual work, thus making this project inherently safer, while endeavoring to sink more efficiently. With that in mind, the team embarked on a design program to improve its overall shaft sinking systems without the requirement for excessive capital and methodology flexibility to adapt to potential changing conditions expected to be encountered during shaft sinking. This was especially important should the new approach be met with less than expected success, and retrofitting of the system was required. The concepts were developed to provide for a much improved work environment, while easing the manual labour burden on the workers with innovative equipment and approach to the work."

Jan 1, 2019

By Stephen Mcgibbon, Tim Twomey

"Abstract - The High-grade Zone (HGZ) was discovered 5000 ft (1520 m) below surface in the hangingwall of the existing orebody, 46 years after the Red Lake mine first went into production. The very rich ore of the HGZ is characterized by a remarkably abundant distribution of visible native gold. The location of this discovery challenged conventional wisdom at the time and its genesis has yet to be fully understood. Textural observations of ore within carbonate veins as well as crosscutting relationships suggest peak-metamorphic emplacement for at least some of the gold. Post-lamprophyre dike remobilization of gold is locally observed in the HGZ. Structure and dilatancy were the key elements for localizing ore at the Red Lake mine. Ore occurs where a fault trend intersected folded ultramafic volcanic rock that created a semi-permeable cap-rock to ore fluids ascending the "feeder" structure. This was enhanced by strong competency contrasts between the eastern ultramafic rocks, felsic volcanic rocks west of the HGZ, and the mafic volcanic host to ore - an exceptional environment for the development of protracted dilatant fluid pathways for gold deposition.Development in the HGZ began in February 2000 and reached commercial production on January 1, 2001 at a capital cost of US $53 million. December 2001 reserves are 1.9 million short tons (1.73 Mt) at an average cut and diluted grade of 2.05 ounces per ton gold (70.5 g/t) containing 3.8 million ounces of gold. The extremely rich ore presented a unique challenge in grade estimation for the Geology Department at the mine. The historic cutting factor was replaced by a statistical method as more data were collected from mining and mill reconciliation. The mine produced 503 000 ounces of gold in 2001. Exploration at the mine is targeting HGZ-type ore formation within basalts associated with the intersections of fluid pathways and folded ultramafic rocks, as well as other targets."

Jan 1, 2001

By Gordon W. Parsons, Ross E. Sampson

"THIS PAPER will trace the work done in bringing the Munro underground ""A"" •Orebody into production to replace the open pit, which was scheduled to be completed early in 1959. Included will be an outline of the exploration work and early planning, and of the final decisions on mining methods. Some of the more detailed work will be described and reasons will be given for the decisions made regarding development work, mine ventilation, ground support, and equipment. Brief mention will be made of open pit operations, as these have had some influence on underground development. Also, some of the main geological features of the ore occurrence will be de-scri0bed, as these had to be taken into consideration when making decisions on ore development and mining methods.LOCATION AND HISTORYhe Munro mine of Canadian Johns-Manville is in Ontario, approximately 50 miles east of Timmins and 40 miles west of the Que-bec-Ontari-0 boundary. The producing orebody is in the southwestern part of Munro township. Property controlled by the Company extends nortl1westerly about 2¥2 miles into Beatty township, on which two other interesting asbestos-bearing zones have been partially expl-0red. Active exploration work on the property was started in March, 194.9, and continued until the summer of 1950."

Jan 1, 1960

By J. Bigu, M. G. Grenier, S. Hardcastle

"This study was undertaken in a belt conveyor drift of an underground hard rock mine. The conveyor transported ore or waste from a crushing operation located upwind from the drift sampling locations. A 250 m section of this drift was selected and several types of measurements were taken. Average respirable concentrations in the drift were 0.43 mg/m3 and 0.19 mg/m3 for total and silica dust, respectively. From the respirable dust concentration profile along the drift, it may be possible to estimate the contribution from extended sources such as dust produced by the belt and return idlers.The airborne dust in the drift had an average mass-median aerodynamic diameter of 4.2 micron. A continuous dust monitor showed that the crushing operation produced fairly high dust concentrations (sometimes greater than 4 mg/m3) over short periods of time.IntroductionAirborne dust in the respirable range is known to be the cause of various forms of lung ailments . In underground mines, respirable dust sources are created at many stages of production. All mining operators are responsible for de signing and establishing means of reducing airborne dust. In some cases, sources of dust are well defined and suppression methods are standard.In the case of interest here, the airborne dust cloud was formed from the contribution from many sources, which may be either discrete or extended. At the experimental site, the discrete or point sources were the crushing operation and the belt conveyor transfer point (tail pulley). These sources may be controlled by proper dust capture and scrubbing systems as well as dilution ventilation. Examples of extended dust sources in the area include dust produced by the re-entrainment of settled particles along the drift. Ventilation air movement and vehicular traffic both contribute to this phenomenon. Dust produced by the conveyor is another example of an extended dust source. Caked deposits on the return strand and idlers as well as the transportation of dry material on the belt, can be major contributors. Proper wetting of roadways and muck as well as proper belt cleaning techniques can help reduce these emissions. The cleaning apparatus, used on the belt where these experiments were conducted, is shown in Figure I. These and other belt cleaning techniques are described in more detail elsewhere."

Jan 1, 1987

By G. E. Norman, R. E. Michelutti

"One of the major objectives of Falconbridge has been and continues to be, to minimize the impact of its operations on the environment around its Sudbury operations.The approach to achieving this objective and the results, are discussed under the following topics .I . Sulphur Dioxide Emission Improvements.2. Effluent Treatment Improvements .3. Effect of the Envrionmental Improvements.Sulphur Dioxide Emission ImprovementsHistoryThe rejection of pyrrhotite in the concentrators is one method of reducing the amount of sulphur to the smelter and therefore the sulphur dioxide emissions. In the 1950s and 1960s, Falconbridge developed the capability to remove 54% of this pyrrhotite. Numerous attempts were made to increase this amount by treating the pyrrhotite for recovery of nickel and in some cases elemental sulphur. Processes tested and operated were: hydrometallurgical pilot plant, roast-leach commercial operation and nickel-iron refinery. None of these processes proved to be commerically successful for both technical and economic reasons. Falconbridge therefore redirected its efforts to reducing sulphur emissions by improving its smelting process under The Smelter Environmental Improvement Project. A major component of this project was the installation of a sulphuric acid plant to recover the S02 in the roaster off-gases."

Jan 1, 1984

By Denni Nikols, Farrukh Z. Khan

"Highvale Mine, located at Wabamun, Alberta, produces thermal coal for TransAIta's Keephills and Sundance generating plants. Overburden stripping in the mine is conducted by draglines which normally operate on top of the overburden bench. In certain areas oj the mine, however, these overburden benches are susceptible to slope failure. In these areas, due to safety considerations, the draglines are utilized in the less productive chop-cutting mode, supplemented by mobile equipment where the bench height exceeds the dragline chop-cutting limit. This paper proposes maintaining the draglines in their normal digging mode through areas of unstable or jailed overburden, by utilizing a dragline carried toe buttress 10 ensure adequate bench stability. The data requirements and methods of slope analysis to design a toe buttress across an unstable highwall area are examined in rigorous detail. INTRODUCTIONLocationHighvale Mine is owned by TransAlta Utilities Corporation and operated under contract. It is Canada's largest coal mine with an annual coal production in excess of II million tonnes. The mine is located approximately 80 km west of Edmonton on the south shore of Wabamum Lake (Fig. I) and production is currently provided by three pits 02. 03 and 04 (Fig. 2). The entire coal production is consumed at the nearby Sundance and Keephills power generating plants.ScopeThe mining operation at Highvale Mine has had occasional slope stability failures of its high wall overburden bench. This paper examines one such failure which occurred in the summer of 1983 at Pit 03. In addition to an investigation of the failure, Terracon was asked to recommend mine operation procedures which would minimize the impact of these slide zones on dragline productivity. A method of removing the failed material by utilizing the dragline in its normal digging mode is designed. The method's advantages and disadvantages as well as the required support procedures are reviewed."

Jan 1, 1989

By M. Sengupta

International trade in minerals plays a very important role in the economic growth of many nations. Several less developed countries a1•e heavily dependent on their mineral exports for earning foreign exchange, which is needed for industrialization. Mineral exporting nations experience many problems in international mineral markets; the most important are tariff barriers, deteriorating terms of trade, instability in metal prices, etc. The formation of international mineral cartels to raise prices can be successful only to a limited extent and only for a short period of time.

Jan 1, 1976

By R. Augsten, K. K. Feng, K. C. Cheng

"Methane emission and the desorption characteristics of vertical borehole coal samples of Greenhills multiple seams in the vicinity of Elkford, British Columbia were investigated. Three vertical boreholes at depths of 335 m, 380 m and 395 m were drilled along the west wall of an active open pit mine and 44 core samples from various coal seams were obtained for desorption studies.The results are presented in three tables and illustrated with six figures. The methane content was found to increase significantly at depths greater than 200 m. The adsorption equation by Kim and the properties of the coal have been used to predict the methane content and these were compared with the measured values by the direct method.IntroductionThe coalification of plant material in the sedimentary rock produces different ranks of co al and gases of various composition. The gas mixtures are retained in coal beds and rock strata under pressure. The gas content in a coal bed varies considerably depending on the rank of coal and the depth of overburden. The gas content is defined as the volume of gases adsorbed in a unit weight of coal materials. The net amount of gases remaining in a coal seam depends on the difference in the rate of generation of methane by geo-thermal heat and the rate of diffusion of the gases out of the coal bed through sedimentary cover. The major factor that causes the change in rank and the liberation of gases is the temperature, which is governed by the thermal conductivity of sedimentary cover and the heat flux through the underlying rocks. The rate of diffusion of the gases out of the coal is governed by the porosity of the overlying rocks and the degree of fracture. The measured values of gas content in major North American coal beds are from zero up to 24 cm3 per gram of coal(1,2). A gas content of 2.5 to 9 cm3/g is considered ""gassy"" and that of 9 cm3/g or higher is considered ""very gassy"" for underground mining(3). Normally, the gas mixtures released from bituminous coal in Canada contain 90 to 98% methane and the remainder is made up of CO2, N2, 02, H2, He and other hydrocarbons(4)."

Jan 1, 1984

"The Val d'Or Division now comprises the Lucien C. Beliveau Mine and Concentrator (formerly the Pascalis, described below) and the Chimo Mine. Cambior acquired an initial 50% interest in the Chimo Mine in May 1989 and the remaining 50% in April 1990. Cambior's share of 1989 production was 2121 ounces; the company expects to net 23 750 ounces from Chimo in 1990. Pascalis MineUPDATERenamed the Lucien C. Beliveau Mine at its official inauguration in September 1989, the mine is exceeding forecasts, producing over 11 500 ounces of gold in the first half of 1990. Cambior expects 1990 production to total 34 000 ounces.IntroductionThe Pascalis Mine is located 16 miles east o f Val d'Or, Quebec, and is accessible by a three mile gravel road off highway 117 (Fig. I).The property is wholly owned by Cambior.The Pascalis gold deposit consists o f a sub-vertical diorite dyke 1000 ft long by 30 ft wide containing quartz and tourmaline veins with inclusions of pyrite and native gold . Three vein systems ca n be seen in the deposit , the most important being tensile veins oriented at a right angle to the direction of the dyke and inclined at 40 degrees. These overlapping veins vary in thickness from 4 in. to 40 in. and occur at intervals of six to ten ft. The deposit is, therefore, very difficult to evaluate; a complete evaluation would require drifts over the whole width of the dyke combined with relatively short drill holes (Fig . 2)."

Jan 1, 1990

By David A. Fawcett

"This paper presents a summary compilation of current Canadian coal research projects in the areas of exploration, mining and preparation. The compilation forms the basis for a review of present operations and technology, and of current research efforts. General research areas, requirements and priorities are suggested along with a discussion on achieving the research goals in terms of funds, facilities and staff. The current level of research funding in these areas is assessed. IntroductionCanada's coal production is expected to undergo major expansion over the next two decades in response to domestic demands on coal for electrical power generation, industrial uses and conversion to synthetic .fuels, and in response to export demands for both thermal and metallurgical coal s. Surface mining will continue to dominate, but underground mining will contribute an increasing proportion to total production.In Canada, coal research, particularly in the areas of exploration, mining and preparation (E, M & P), has been limited. Increased impetus has recently been given to this research with expansion of CANMET's activities and with the establishment of the Coal Mining Research Centre (CMRC). University researchers are branching into coal research; strata mechanics and preparation are popular in mining-related fields.With the increase in number of organizations and individuals involved in coal research, a means of keeping abreast of the ongoing work is necessary. An annual summary of the status of and developments in current research assists in providing this information. The CMRC prepared such a summary for Canadian coal E, M & P research in 1979 and it received favourable response, justifying the effort. A 1980compilation has been prepared and pro vides the basis for this paper; it is presented with a brief discussion on background, format and content.The compilation forms a basis for an examination of the current status of Canadian technology in E, M & P and of the ongoing research in each area. General research requirements are reviewed and programs and tasks are suggested, followed by a discussion of research goals in term s of priorities and achievement. An assessment is made of the level of research funding in Canada, with comparisons drawn from the United States, the United Kingdom and Australia."

Jan 1, 1980