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By M. R. Henzinger, G. Lenz, A. Gaich, Pötsch, W. Schubert, P. Wagner

"The better the information on the rock mass and its fracture system, the better is the basis for any rock mechanical decision that is required during the excavation process. While in conventional tunnelling free view to the tunnel face is available, possibilities are limited for mechanised tunnelling using a tunnel boring machine (TBM). An approach, already formulated in 2005, is used that produces digital photographs through openings in the cutting wheel of a TBM and merges them into a circular three-dimensional image. The 3D image is then used for geometric rock mass characterisation purposes including geological mapping, for example to measure spatial orientations or determine joint spacing. In the paper the basic concept is described together with first results from a pilot test.INTRODUCTIONA three-dimensional image unites digital photographs with spatial information on the objects/surfaces it shows. Since they combine geometric and visual information they are a straightforward source for geometric rock mass analysis and geological mapping. Their obvious benefits among others are: (i) they allow spatial measurements even in inaccessible regions, (ii) they provide objective and reproducible records of the rock mass conditions, and (iii) they increase working safety (Gaich et al. 2004).Pre-requisite for the generation of 3D images is the acquisition of at least two photographs from the region of interest. From the photographs the imaged object surfaces are reconstructed by means of image analysis using methods from photogrammetry (Slama, 1980) and computer vision (Hartley & Zisserman, 2001). See also Figure 1."

Jan 1, 2015

By P. K. Kaiser, S. Maloney, S. Yazici

"This paper focusses on the strength or capacity of cable bolts and introduces a new perspective for cable bolt design by demonstrating that mining-induced stress changes may affect cables in a detrimental manner. The concept underlying a novel cable bolt pull-out resistanceor bond capacity model is described and its practical significance is demonstrated by application to a simple two dimensional scenario of a fall-of-ground.A number of practical implications emerging from the application of this model are discussed to provide guidance to ground control personnel jar improving cable bolt support systems in mining applications. These include cable layout optimization, use of cable pre-reinforcements, assessment of embedment length requirements, need for plated cables (or straps), use of bird-caged cables (or buttons), and grout quality issues.IntroductionDuring the last decade, cable bolting has become a standard support technique in mining for handling wide spans, reinforcing are passes, preventing or reducing dilution of ore in marginally stable stopes, and for many other rock support need s.In its infancy, many deficiencies in cable bolt supports resulted from improper installation techniques and, in particular, grout quality control problems and the use of empty breather tubes (Goris, 1990). The development of special grout pumps and fail proof placement procedures (Oliver, 1992; Bourchier and O'Flaherty, 1992) have eliminated many of these early problems. Nevertheless, there are still situations where cables seem to lose their capacity during mining, and in these cases the cables do not provide the expected and needed ground support. In some instances, cables perform extremely well, whereas in others the same support layout and quality of support installation seem to be insufficient, allowing falls-of-ground or progressive cavings to occur."

Jan 1, 1992

By A. A. Burgoyne

"The McDame chrysotile asbestos deposit located near Cassiar in northern British Columbia isfound at depth and on trend to the southeast of the currently mined open-pit Cassiar asbestos deposit. The ultramafic rock hosting the McDame is serpentinized peridotite of the Upper Paleozoic Sylvester Group contained in an ophiolitic sequence preserved within a lower thrust sheet of the Sylvester Allochthon. The Sylvester stratigraphic package is a series of thrust slices composed of argillite, tuff and volcanic flows, diorite and serpentinite. Contacts between units are often fault-controlled.The McDame asbestos-bearing ultramafite is considered to represent a separate interleaved fault-bounded slice of rock distinct from the Cassiar asbestos deposit.Asbestos mineralization of the McDame deposit was discovered in /978. Exploration during /980 and /98/ focused on extensive underground drilling of the deposit and in /983 on geological mapping, airborne and ground magnetic surveys. In /984 a 622.5 m borehole was drilled with a 242 m intersection of McDame ultramafite of which the lower 15/ metres contain potentially economic chrysotile asbestos. The McDame deposit averages 90 m thick, trends north-south, dips easterly and plunges southeasterly. The deposit is estimated to contain geological reserves in the order of 62 million tonnes containing asbestos fibre similar in value to the Cassiar deposit.The McDame is considered a major world-class asbestos deposit. A decision to develop and mine the deposit will require further substantial underground exploration and evaluation. A + 1200 m exploration adit driven to the hanging wall of the deposit was undertaken in 1985 in anticipation of bulk sampling and diamond drilling in 1986."

Jan 1, 1986

By Gene O. Cowie

"Zinc, which once enjoyed an unchallenged position in the field of decorative applications, has lost a substantial share of its markets to other materials, particularly plastics. This turn of events has led the zinc industry to explore new market areas, particularly those applications where the engineering properties of zinc can be utilized. This paper gives an overview of the zinc industry's efforts to develop the data base and product development technology which have enabled zinc alloys to emerge as engineering materials. It also indicates those areas in which the research facilities of the zinc industry must be employed to ensure that zinc alloys keep pace with developments in competitive materials and processes.The Materials RevolutionThe development and utilization of new materials and manufacturing processes progressed for centuries by evolution. Recently it erupted into a revolution, which may become as significant as the industrial revolution. The materials revolution has impacted upon many industries, but none has been affected more traumatically than the North American automotive industry. The plight of that industry is of great importance to us because their problems have, to a great degree, become problems to the zinc industry.Much of the impetus behind the automotive trauma came from the battery of motor vehicle regulations promulgated by the United States government in the 1970s. These regulations required that the efficiency of passenger cars, in terms of miles per gallon, be approximately doubled in ten years. In view of the fact that major changes in the automotive world require three years of lead time to implement, the industry was left with only seven years to perform the task. The automotive industry was simultaneously required to make progress in other areas, such as reduced emissions, reduced cost of repairs and increased levels of occupant safety. These added demands not only diverted some of the available resources away from efficiency goals, they often ran in direct conflict. For example, when you are required to provide a front bumper which will absorb the energy of a 5-mile -per-hour barrier collision, you must add both hardware and structure to the vehicle. This adds weight, and increased weight reduces miles per gallon."

Jan 1, 1983

By I. Filzwieser, S. Konetschnik, A. Filzwieser, A. Anzinger

Production in copper electrorefining tankhouses mainly depend on two factors: The deposition area, which is a result of the amount of installed cells and cathodes, as well as the current density - the amperage per square meter of deposition area. The present paper shows, that the most economical way of achieving a certain production is to maximize current density by using the METTOP-BRX-Technology - as building and infrastructure can be kept more compact. This industrial proven technology applies a parallel electrolyte flow in each electrolysis cell. In 2011, the first fully industrial applications started up: At the secondary smelter Montanwerke Brixlegg AG, 156 cells are equipped with the METTOP-BRX-Technology; this allows a current density of 390 A/m². Xiangguang Copper Co., Ltd. - a primary smelter and refinery - operates its new tankhouse (720 cells) at 420 A/m²; this stands for an production increase of 50% compared to the same sized ISA tankhouse which is limited to 280 A/m². The first part of the present paper gives a cost comparison between a conventional copper electrorefining tankhouse and a high current density tankhouse when assuming a Greenfield project. The second part describes the cost savings when installing the METTOP-BRXTechnology in an already operating tankhouse.

Jan 1, 2014

By Young C. Kim

A proper economic analysis of pit slope design must reflect the trade-off between the benefits and the increased risk of slope failure inherent in steeper slope angles. However, no formal framework for a proper analysis has existed to date. This paper summarizes the material contained in the Design Chapter Supplement (5-3) of the Pit Slope Manual. The supplement describes the results of the research effort in which a formal economic analysis framework was developed and tested through a case study. The case study results have demonstrated the practicality of the developed procedure and the availability of required data under "real-life" conditions.

Jan 1, 1979

By G. A. Davidson, P. G. Williams

"New developments in centrifugal slurry pump technology are discussed in relation to their importance for improving pump operation and reliability.Experimental data obtained by measuring the velocity of liquid flows in a slurry pump casing using Laser Doppler Velocimetry are presented. This demonstrates the importance of selecting pumps with the proper hydraulic design to provide optimum efficiency, maximum part life and minimum operating cost.The paper also discusses the use of new wear resistant materials, such as ceramic/metal composites, which can significantly improve the life of parts exposed to abrasive media. The results of laboratory attrition tests are presented. IntroductionCentrifugal slurry pumps are of primary importance for the hydro transport of abrasive and corrosive media in the mineral processing industry. As for all process equipment, slurry pumps must be carefully selected and operated to provide optimal performance. To achieve this, it is necessary to select equipment which will provide efficient and reliable operation for the specific service conditions and incorporates the best materials available to obtain maximum parts life.Abrasive wear of liquid end components is the most important aspect that distinguishes the design and application of slurry pumps from other types of pumps. It is therefore necessary to have a fundamental understanding of the mechanical interaction between pump components and the media being handled, as this will impact significantly on hydraulic design, mechanical reliability and selection of wear resistant materials. Recent advances in computational approaches'» have greatly improved the prediction of wear rates in pump casings by facilitating the solution of complex equations which describe the wear mechanisms mathematically. In conjunction with this, new experimental techniques allow researchers to measure flow fields in pump casings using non-invasive devices such as Laser Doppler velocimeters."

Jan 1, 1992

By B. Stuckert, P. Sheehan, J. Balfour, B. (Manas) Das, D. Fawcett

"With the growth of large scale surface mining operations, waste disposal and stability of waste dumps pose a challenging problem to engineers. Vibrations due to blasting operations proximal to these dumps further complicates dump design. Many dumps which are statically stable may become unstable due to the effects of blasting vibrations.A joint project between CANMET and Smoky River Coal Ltd. has been initiated to study the dynamic stability of waste dumps. The study involves development of an analytical algorithm combined with field monitoring to assess dump performance.Another objective of the study is to provide baseline data for a vibration attentuation relationships for sedimentary rock (coal) environments: most studies to date are for base metal mines. The effect of dump thickness on vibration response is also addressed.The key objective of the study is to present a methodology for assessing the dynamic stability of waste dumps. Implicit in this methodology are a number of assumptions concerning vibration attenuation in sedimentary rock environments, and response of the dump material to induced vibration. Where possible, these assumptions have been compared with monitoring data as a check on their validity."

Jan 1, 1989

By C. F. Harris

Following the initial development of the zinc-lead blast furnace, efforts have been directed both at increasing the scope of the process and increasing the cash return. The paper reviews the process developments which enable the process to smelt efficiently a range of material which encompasses high-grade zinc sulphide concentrates. mixed concentrates, Waelz oxide, zinc ashes and other materials blended to give a furnace feed ranging from 25 to 65% zinc and from 1 to 25% lead, with a copper-lead ratio exceeding 1 to 8. The paper also reviews the process developments which have enabled the capacity of a furnace and condenser system of standard size to be boosted from 30,000 to 80,000 tonnes/annum. The benefits achieved are used as a justification for continuation of the development of the zinc-lead blast furnace. Predictions are made of the benefits expected from further developments.

Jan 1, 1979

By Stephen G. Hardcastle, Michel G. Grenier

"Safety and health issues are and have been in the last decade a very high priority item with all parties involved in the Canadian mining industry. As a result of this high level of concern for workers' safety and health, Canadian mines are at the leading edge of environmental control technology. For the most part, the occurrence of pollutants in mines is unavoidable. Dust from mining operations, airborne radiation, gases and heat from the strata as well as gases and particulate from diesel engine emissions will undoubtedly be found to some level in most Canadian mines. A lot of work remains to be done, however, in order to bring all Canadian mines at the same level of proficiency when it comes to safety and health. Also, more work is needed in order to maintain our status as world leaders in this field.CANMET's Mining Research Laboratories (MRL) in Elliot Lake and Bells Corners, Ontario, with the cooperation of the mining industry, have contributed to improving environmental conditions in underground and surface mining and milling operations. The extent of collaboration and efforts vary widely from long-term, multi-million dollar projects between several interested parties to smaller projects involving one laboratory and a single mining operation. This paper gives examples of such collaborative efforts and potential future directions as they apply to: mine ventilation analysis using tracer gas techniques, optimization of mine ventilation network efficiency using real-time monitoring and controlled recirculation (heat saving), respirable dust and radiation sampling and control techniques, diesel emission control using regenerative ceramic filters and, finally, the control of sulphide dust explosions and resulting sulphur dioxide production."

Jan 1, 1990

By P. Farsangi, A. Hara

"Kidd Creek Mines places approximately 10 000 tonnes of consolidated rockfill on a daily basis. Consolidated rockfill is comprised of sized aggregate mixed with different ratio and amounts of binders. Consolidated rockfill, with closely controlled specification, is employed for subsequent pillar recovery and improved passive active/ ground support. With the same amount of cementing agents consolidated rockfill mass yields a higher, compressive strength, modulus of elasticity, cohesion, and angle of friction compared to a typical cemented hydraulic fill mass.The consolidated rockfill at Kidd Creek Mines is designed to sustain not only the gravitational loading of the overlaying fill material, but also to some extent the dynamic loading applied during blasting of the adjacent stopes and/or pillars.The quality control of materials used in Kidd Creek's rockfill system could be effected in three stages of handling: (1) at the surface backfill plant; (2) during transportation; and (3) placement of the fill.The emphasis in this paper is placed on individual stope backfill design and quality control measures at Kidd Creek Mines to place fill in large-scale open stopes which eventually could be exposed on all four walls during pillar recoveries."

Jan 1, 1993

By Tim J. Carew, Dennis C. Martin

"One approach to stabilization of rock slopes is to place a buttress at the toe of the slope to provide additional resisting forces and increase the length and strength properties along the failure surface. This paper describes the rock mechanics and mine planning aspects of incorporating a buttress of intact rock in the lower part of the slope as part of the slope design for the south wall of the final pit at Cassiar Mine. Stability analysis techniques and results are described. Analyses results have indicated that, in order to maintain steep over-all slopes in the final pit, a buttress of intact rock shoud be incorporated into the lower section of the slope until late in mine life. The effect of the buttress is to flatten the slope and reduce the slope height thereby improving slope stability. The mining plans would be such that the buttress would be mined out during the last four months of mining when the consequences of instability would be least severe.IntroductionThe concept of using a buttress to stabilize slopes has been used in mining and civil engineering construction in may locations (Richards and Stimpson, 1977). Most buttresses involve placement of coarse rock fill timber cribs or other material as a load at the toe of an already unstable slope to provide forces which resist failure by counteracting driving forces and increasing the length and strength of the failure path.This paper describes the geotechnical and mine planning aspects of incorporating a buttress of intact rock in the design of the south wall of Cassiar Mine. The effect of an intact rock buttress is to flatten the slope and reduce the slope height, thereby improving slope stability. No actual construction is required other than normal excavation of the slope. The ""mine plans would be such that the buttress would be mined out at the end of mine life when the impact of instability would be less severe and additional ore might possibly be recovered from the slopes. Mining of the buttress could induce instability at the very end of mine life at a time when maximum ore extraction has been achieved."

Jan 1, 1986

By L. Dekker

"In 1979 Chevron Standard Limited and Irving Oil Limited intersected a thick, high-grade sylvinite zone in the Windsor Group in the Chevron Irving Malagawatch No. I well in central Cape Breton. This well was the third and final hole of a program designed to evaluate a non-commercial oil discovery made by Chevron Standard's Mineral Staff in 1978 while carrying out base metal exploration. Nine holes were subsequently drilled to evaluate the significance of the potash discovery. The delineation drilling proved the Malagawatch structure to be complex with the potash zone showing erratic grade and thickness distribution. Based on the drill information the potash accumulation at Malagawatch is uneconomic, however, other salt ""structures"" in the Bras d'Or Basin may in time prove to have better potential.History of DiscoveryIn 1972 Cuvier Mines discovered the Gays River lead-zinc deposit (MacEachern and Hannon, 1974) which prompted Chevron Standard's Minerals Staff to carry out a study of the Windsor basins in Nova Scotia (Figs. I and 2). As a result of this program several carbonate-hosted lead-zinc prospects were identified in the basal Windsor carbonate; one of these was at Malagawatch on Cape Breton Island . In 1978, after preliminary exploration surveys, a diamond drill program commenced consisting of 5 BQ holes (Fig. 3), three of which tested the basal carbonate. Instead of the reefoid bank facies of the Gays River Formation (Giles et al., 1979), the favoured host for economic base metal mineralization, this carbonate was developed as a laminated, pelletoidal, lime packstone more characteristic of the facies equivalent Macumber Formation (Schenk, 1967). While drilling one of these holes, No. 3-78, oil scum was intermittently detected on the drilling mud. The hole was abandoned at 191 m in anhydrite, without having reached the basal limestone."

Jan 1, 1985

By M. J. Medd, G. A. Speirs

"This paper describes the simultaneous sinking and equipping of a 4.9 m diameter concrete-lined shaft to a projected depth of 1660 m. The shaft blast design utilizes the full face method using a parallel hole burn cut. Hydraulic drilling and a totally redesigned Cryderman-type mucking unit were integrated into the four deck sinking stage to provide for drilling, mucking, concreting and shaft steel equipping operations. A safety program was tailored and implemented specifically for this shaft sinking project.IntroductionIn July 1988, Falconbridge Limited commenced development of its Thayer Lindsley exploration site located some four km north of Sudbury on Regional Road 80.The first phase of this project was awarded to J .S. Redpath Mining Consultants Limited and the scope of work included the engineering and project management to construct a surface plant capable of supporting a shaft sinking and exploration program for potential future mine development. This initial phase of the project was completed on schedule and under budget on December 23, 1988, and is the subject of an independent paper.In November 1988, J.S. Redpath Limited was awarded the shaft sinking and exploration phase of this project. The scope of work consisted of sinking and equipping a 4.9 m diameter shaft to a depth of 1660 m and carrying out the development and diamond drilling on two levels. This work was scheduled to be completed by November 1991.The T .L. Exploration Project is located toward the eastern end of the south range of the Sudbury basin, north of Sudbury. Figure 1 details the projected mining area and the shaft location on the geological complex. Figure 2 is a section showing the exploration shaft that is located in the Norite. Two levels will be developed from this shaft, on the 1310m and 1588 m levels, to provide access for further geological examination of the ore bodies."

Jan 1, 1991

By B. R. Schneiders

"Atikokan is 200 km west of Thunder Bay and earned its mining fame from the discovery of the Steep Rock Iron Range in the late 1930s. Gold, however, was discovered in the Atikokan and Mine Centre areas in the late 1800s and eventually led to one of Ontario's first gold camps, and a total production of approximately 52,000 oz of gold and 174,000 oz of silver from 218,000 tons milled.The general geology of the area consists of Early Precambrian rocks of the Wabigoon and Quetico subprovinces, separated by the east-trending Quetico Fault. The Wabigoon Subprovince, to the north, consists of metavolcanics, minor metasediments and granitic batholiths. The Quetico Subprovince consists of metasediments and granitoids. Small ultramafic plutons occur throughout the metasediments.Within a 50-km radius of Atikokan, more than 50 gold occurrences, prospects and past producers have been discovered since the 18oos. The Atikokan Gold Study performed by the Ontario Geological Sur vey (Wilkinson, 1980, 1982) defined three types of gold mineralization in which gold is concentrated in quartz and quartz-carbonate veins:I) Metavolcanic-Hosted, Stratabound Type-associated with altered felsic fragmental units and chemical sedimentary rocks; possible gold mineralization source rocks. The mineralization is due to metamorphogenic (epigenetic) enrichment. Associated with dynamic metamorphism events and/or felsic intrusive events.2) Marmion Lake Batholith Type-occurs within the gneissic core of the batholith associated with north east-trending lineaments, representing faults or shear zones. Mineralized veins are related to several periods of deformation and shearing, suggesting that metamorphogenic veins were produced during dynamic metamorphism.3) Contact Zone Type -occurs in the contact zone rocks between gneissic batholiths and meta volcanic belts. Hydrothermal solutions produced during several deformational periods acted to leach and concentrate gold mineralization. Localized, discontinuous shear zones host the epigenetic (metamorphogenic) veins.Twenty-one properties in the area were mapped and sampled, and researched petrographically and geochemically. Geological data from the Atikokan Economic Geologist Program of the Ontario Geological Survey are used in discussing the types of mineralization, genetic models, and exploration targets and techiques."

Jan 1, 1983

By G. H. Blackwell, A. J. Sinclair

"The main components of a ""PC” -based mineral inventory system are described in a sequence common to many real reserve/ resource estimation projects and in the practical context of problems and decision-making typically encountered in such studies. Some components are designed particuarly to improve the geostatistical instructional capability of the package. An important part of this approach involves the use of widely available software for data manipulation and evaluation in the design of a mineral inventory study progressing to mine design and feasibility. A variety of more or- less fixed routines written in high level languages provide acceptable computational speeds on a personal computer. These critical segments are linked by simple, short, compiled Basic programs easily adjustable to various data configurations and needs. IntroductionGeostatistical mineral inventory estimation has progressed greatly since its slow dissemination during the 1960s. The mining industry generally has accepted the benefits of the technique, notably the quantification of grade and geology, an indication of error in grade estimation, and of the mined volume / grade variance relationship (Clark, 1979, Isaacs and Srivastava, 1989).Acceptance has been slowed, first by complexities of geostatistical theory and second by a bewildering variety of computer systems and applications programs. Continuing improvements in education will facilitate a better understanding of the underlying theory.The purpose of this paper is to describe, in a practical context, the development of a geostatistical-based approach to reserve/resource estimation. The approach integrates various existing commercial software packages with a wide selection of programs developed by the authors for personal computers which estimate mineral inventories and educate users in the techniques applied; that is, the QMIN system.It is hoped that the approach presented here will convince mining and geological engineers concerned with resource estimation, of the soundness of geostatistical methods and its broad potential to their problems."

Jan 1, 1992

By D. Kovachevich, M. A. Pfeifer

"A t remote locations typical of mines and associated ore processing plants, diesel electric generators are ideally suited for power plants due to their inherent operating flexibility, efficiency and reliability. In recent years rapid escalation in fuel and related transportation costs has made extensive waste heat recovery from generating sets financially attractive to a much greater extent than previously.The paper outlines key considerations during planning and design stages for utilizing the various waste heat sources available to best advantage. Based on two /980 mining projects built in the Canadian Arctic, data is presented on potential operating and capital costs savings. A review of heat balances, engineering flow diagrams and major equipment selections for process and building heating systems utilizing waste heat is included.IntroductionResource projects increasingly occur in remote areas requiring on-site self sufficiency in electrical power generation. For such projects, the low- or medium-speed turbo-charged diesel engine is very often the preferred choice as a prime mover for the generating sets . It is inherently reliable, has good response to load changes and has comparatively high fuel efficiency over a wide load range . From a project execution standpoint, It is capital cost- competitive and procurement lead-time normally ' fits ' within tight schedule constraints. In addition, its potential for waste heat recovery is excellent , particularly in northern climates where space heating requirements are usually substantial, and also where there a re requirements for heat for process and plant services.The high cost of fuel , with add-on transportation costs , provides a major incentive to fully exploit the available waste heat recovery potential o f such installations.As a result of the rapid escalation in the price of petroleum products following major crude oil price increases in 1973 and again in 1978-79, liquid petroleum fuels, having the desirable properties of comparatively high heat content and transportability, are no longer 'cheap' commodities and have become so valuable that industry has widely undertaken serious conservation efforts.Currently, it appears that petroleum cost trends of the 1970s may not continue, at least in the near term, and that we may see somewhat reduced energy costs for a time. In the longer term , and certainly within the life spa n of major projects, however, it is generally believed to be inevitable that these fuels will be increasingly expensive . Energy costs are today a major operating cost for remote minerals processing plants and will remain so for the foreseeable future.In order to meet the economic challenge posed by high energy costs, future projects should be thoughtfully planned from the outset with the goal of minimizing energy requirements and maximizing the use of waste heat recovery to meet such requirements. There is also considerable potential for significant energy savings by retrofitting of existing installations."

Jan 1, 1984

By A. McIntyre, L. R. Plitt

Both the Bond and the Hardgrove grindability tests are widely used in the mineral industry to measure the ease of the comminution displayed by a material. The Hardgrove test is mainly used for coals, whereas the Bond grindabifity test is mainly applied to hardrock minerals. The Bond grindability has the advantage that it can be empirically related to the energy required for comminution (work index), whereas the Hardgrove grindabifity test has the advantage of being easier to perform. In an effort to establish a valid correlation between work index and Hardgrove grindability, a series of parallel grindability tests were carried out on a wide variety of rocks and minerals. The standard Hardgrove test was modified to allow for materials with a higher density than coal. A new, satisfactory relationship was established which permits rapid estimation of work index from Hardgrove test data.

Jan 1, 1980

By A. Liard, H. Sommelet, G. Sauriol

"Description des études qui ant conduit à la conception spécifique du système de drainage de la mine à ciel ouvert. Les approches différentes sont examinées ainsi que la valeur du système recommande.IntroductionLa Division Mines Gaspé de Mines Noranda Ltée exploite un gisement de cuivre par mine souterraine et mine à ciel ouvert à Murdochville, Québec. L'exploitation par mine aciel ouvert a commencé en 1965 avec une operation à flanc de montagne. Elle se poursuit actuellement sous Ie niveau de la vallée dans une fosse dont Ie diamètre est de I'ordre de 800 m (2,600 pi), et la profondeur de 150 m (500 pi) sou s Ie fond de la vallee. Elle doit atteindre une profondeur de 360 m (l, 180 pi) sous Ie fond de la vallee , avec des murs hauts de 360 à 490 m et des pentes moyenne de 44°. Le rythrne d'extraction est actuellement de 85,000 tonnes par jour.Dans Ie cadre des etudes entreprises par les Services Techniques de la Division Mines Gaspé, la compagnie Géomines Ltée a été consultée pour étudier les conditions hydrogéologiques et hydrologiques locales et participer a la conception d'un système de drainage superficiel et souterr ain. Un tel systerne de drainage visait: a éviter les importantes venues d'eau qu i affectent I'exploitation en periode de crue; amaintenir les pressions hydrostatiques au sein des parois de la fosse dans les limites imposees par les etudes de stabilite des pentes réalisees par la Mine.Les principales étapes de cette etude ont porté sur: la collecte et la compilation des données sur la géologie, l'hydrologie et l'hydrogeologie du site; . la détermination des caractéristiques hydrauliques du milieu rocheux à partir d'études structurales et de test s de perméabilité;"

Jan 1, 1981

By John E. Udd, Peter Leinberger, Roman Kozarycz

"This paper is based on work done by the authors in a study of the structural features at a quarry excavated in Chazy limestone on the Island of Montreal. Observations on failures on the quarry walls and benches were recorded, and back analyses of small-scale failures were carried out, thus enabling an assessment to be made of the in-situ strength properties of the rock. Using this information, and data from shear tests in the laboratory, the authors made an analysis of the stability of the south wall of the quarry.IntroductionQuarrying, and excavating for foundations, in the Montreal area involves the removal of million s of tonnes of rock on an annual basis. Even when compared with the quantities mined at major open-pit mining operations, the production figures are impressive. At present, for example, crushed stone is produced at almost 20 quarrying operations either on, or near, the Island of Montreal. The annual capacities of the larger quarries are in excess of one million tonnes each. Lesser, but still substantial, production is achieved at the smaller quarries.Excavations, for foundations , especially during periods of peak construction activity, must also involve large quantities of rock . The writers, however , are not able to produce an estimate of the actual annual tonnages originating from excavations."

Jan 1, 1981