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By R. L. Guerguerian, Eugene Bercel

"Grinding mill hydrostatic trunnion bearings require an external pumping source to provide and maintain the oil film between the bearing members. In order to guarantee a predetermined minimum film thickness, the lubrication system tends to be oversized. The oil film is ""indirectly"" controlled by flow, pressure and temperature monitors with fixed settings on the conservative side. This can lead to excessive maintenance and abbreviated life for the lubrication system components. A reliable method of monitoring actual film thickness would not only provide greater mill availability, but also minimize maintenance costs.This paper describes the instrumentation installed in Dominion hydrostatic bearings, and presents results of field tests where the output of that instrumentation was recorded under various operating conditions.IntroductionThe trend toward larger and more sophisticated grinding mills has made the operators of these machines increasingly vulnerable to financial loss, as the cost of downtime and repairs has increased directly with machine size. In order to guard against such losses, it is becoming imperative that large, sophisticated grinding mills be equipped with protective instrumentation to monitor some of the critical operating parameters and to identify events and trends which, if they go unnoticed, can lead to excessive maintenance costs and machine downtime. The idea of protective monitoring systems is not new. The operators of certain types of machinery where a high degree of safety is required or where machinery health can deteriorate very rapidly, as in the case of high-speed turbo-machinery, have long been using protective instrumentation on their machines. The increased awareness of the benefits of monitoring machinery conditions and the availability of reliable and relatively low-cost instrumentation of a large range of sophistication is making the practice now widespread. Traditionally, grinding mills have not been considered as high-risk machinery requiring instrumented protection. However, the trend, mentioned earlier, toward employing fewer, but larger capacity, mills increases the risk of significant disruption of production, and therefore measures to minimize the risks are desirable."

Jan 1, 1981

By John F. Gartner

"New terrain maps provide information on the ground conditions in northern Ontario. This information has a relevance to mineral exploration because it assists the user in determining ground conditions prior to entering the area. The prospector, geologist, geophysicist and geochemist can then plan for the optimum use of exploration techniques best suited for theseground conditions.These terrain maps are the result of the Northern Ontario Engineering Geology Terrain Study-a program carried out by five consultants under contract to the Ontario Geological Survey of the Ministry of Natural Resources. The area mapped is 370,000 km2 and more than 100 basic data maps at a1:100,000 scale will be published.An unique terrain legend was derived to facilitate the mapping and it allows the derivation of specific user information. Examples of some of these uses are described. Introduction""Where did all the boulders come from Charlie?"", asked the student, as the prospector and his young assistant clambered through the bush. "" Why son, they were brought down here by the glacier"", the prospector replied. ""But where is the glacier now Charlie? "", persisted the young man. ""Gone back up north for more boulders son!""An old story, but one that illustrates the importance of overburden to the prospector. The use of overburden as a prospecting technique is not new. In fact, the principles have been known in the western world for at least 235 years (Shilts 1976). More recently, Dreimanis's classic work on boulder tracing (1957) and Lee's work (1971) emphasize the role of glacial geology in prospecting. In addition, papers by Smee and Sinha (1979), Averill (1978), Bereton (1978), and Gleeson and Hornbrook (1974) all describe the importance of drift in mineral exploration programs. The discovery of the copper deposit in the northern Ontario township of Currie (Thompson, 1979) is attributed in part to till prospecting methods. So the significance of the overburden is firmly established, both in the literature and in the minds of today's prospectors, geologists, geophysicists and geochemists."

Jan 1, 1981

By M. Walmsley, D. Maynard

"This paper describes the use of terrain and soil information in the planning of mine developments, particularly in satisfying many of the existing provincial regulatory requirements. It is also noted that, if properly used, this will provide a solid data base for cost-efficient and environmentally acceptable land use.IntroductionIn planning the development or expansion of a new or existing mine, engineering alternatives are judged on many factors, one of which is the environmental influence. Ecological investigations, ensuring consideration of a rational approach to managing land use and environmental impacts, should be carried out prior to a final decision being made on mine development. The Pit Slope Manual (CANMET, 1976) suggests that both baseline aquatic and terrestrial data be collected and interpreted in such pre-mining surveys. In British Columbia, planning procedures now exist which incorporate biophysical studies to help identify, assess and manage major environmental impacts associated with mine development.Methods outlined in the Guidelines for Coal Development (E.L.U.C., 1976) have been successfully applied in recent years. Following this example, the Inspection and Engineering Division of the B.C. Mineral Resources Branch prepared guidelines to help expedite the development of new base metal mines (Procedures for Obtaining Approval for Metal Mine Development; Ministry of Energy, Mines and PetroleumResources, 1979).The metal-mine guidelines require the proponent of a new mine development project to prepare a two-stage assessment proposal which systematically moves from a preliminary feasibility study (Stage I) to a final project design (Stage II), including application for regulatory approvals. One purpose of the Stage I report is to provide a description of the existing environmental conditions that could be affected by the proposed development. A preliminary environmental impact assessment should also be reported. The Stage II report will contain detailed assessment and management of environmental impacts."

Jan 1, 1981

By J. W. M. Porritt, M. P. Brameld, R. H. McCorkell

"Soil-gas Rn was measured by two types of alpha-particle-track detectors, by emanometry and by counting alpha-activity on Rn-decay-product collectors. Soil samples were analyzed for V by fluorimetric and fission-track methods, their Rn-emanation by decay-product collectors and their total alpha activities with track detectors. The same uranium anomalies were revealed by each method. Fission-track analysis of leaves for V showed only random variations with sampling site, and the Rn emanation of trees and leaves removed from them was barely detectable . The agreement among the other methods is significant, total alpha and collector methods are simple, rapid and useful, and a combination of methods at a site would reveal disequilibrium in the U-decay series if present. Track-Rn measurements are highly reproducible and insensitive to apparatus design and their sensitivity is not enhanced by covering the detectors with thin foil or placing them in large containers.IntroductionIn the past two years , a number of methods of geochemical exploration for uranium have been tested by the authors over the known copper-uranium occurrence at South March, Ontario. This was done partly to compare methods and partly to develop and test new ones. The South march deposit has been described a number of times by others(1,2,3,4). The methods included in this study were the following.Emanometry, Radon in soil gas is measured by pumping the gas into the cell of a scintillation counter or emanometer(5,6). Alpha particles from radon (222Rn) and its decay products (218Po and 214Po) produce scintillations of light in the silver-activated zinc sunphide (ZnS(Ag) covering the walls of the cell. These are counted by a photomultiplier tube and scaler, the count ra sulphide (ZnS(Ag) covering the walls of the cell. These are counted by a photomultiplier tube and scaler, the count rate being proportional to the concentration of radon in the soil gas."

Jan 1, 1981

By P. A. Verhey

"This paper describes a series of wear-resistant ceramic materials which have been successfully used in the mineral processing industry in Canada. Applications include use with metallic ores, coal, potash and asbestos, and in other processes where wear degradation is of major concern. The paper will also deal with considerations involving the selection of the different ceramic materials available. It will cover the installation of ceramic materials on support structures under varying process ' conditions, as well as the other physical and chemical factors which have to be taken into account.IntroductionIn the mineral processing industry, large volumes of ores tailings and other materials are handled. The abrasive nature of most of these materials results in extensive wear to both handling and processing equipment.Wear ratios versus cost, production losses due to down time and wear-resistant material suitability for a given application all demand particular attention when viewed against the need for increased efficiencies in existing processes. As a consequence, a very active continuous search for materials with improved wear resistance has been carried out for many years.In this search, starting about 20 years ago, dense ceramic materials were tested and evaluated in certain applications, notably in the iron ore and asbestos operations in Eastern Canada. As a result of substantially better performance both in continuous extended life and ultimate economics realized , wear-resistant ceramic applications developed progressively in many other processing applications, replacing traditionally used materials.In the vast majority of wear-resistant ceramic applications, considerable extended life over previously used materials was established. This invariably was not just a fractional increase but, in most cases , in factors of double, triple and often all the way up to 18 and 20 times the life of alternative materials used previously. In certain applications, extended life could not be measured and appears to be indefinite.Obviously, as a result of such experiences, the progressively wider use of wear-resistant ceramic materials is now an established trend."

Jan 1, 1981

By A. Lawson

"Continued and expanded use of underground diesel-powered equipment is considered desirable in order to achieve necessary production capability, particularly when coal becomes increasingly in demand as an energy source. Although diesel engines are derated for underground use, concern has been expressed in many quarters regarding the health effects of worker exposure to diesel-generated particulate and NOx emissions. This concern will increase as Canadian diesel fuel quality becomes heavier and with higher sulphur content. This could result in a requirement to increase ventilation rates by 50%.This paper describes the results of studies of various approaches designed to reduce diesel emissions. Two major approaches have been followed: fuel modification, and emission control hardware development. The results of progress in the development of these approaches will be described.Fuel modification includes the application of water/diesel and methanol/diesel fuel emulsions to the engine. Details of the techniques employed in this approach will be described, together with the effects on diesel emissions. (The paper is concerned with the emission aspects only, not the possible major engine modifications and/ or substitute materials of construction for 100070 methanol.) Use of methanol has the added advantage of acting as a diesel fuel substitute and extender, and there are expectations that underground diesel engines could eventually operate on close to 100% methanol fuel, thereby eliminating particulate emissions. The results of emission control hardware development will also be presented and will include the effects of catalysts, water scrubbers, exhaust filters and exhaust gas recirculation techniques on emissions. A combined systems approach employing a number of these components appears to be the most viable method of controlling the complete array of diesel emissions.This work should culminate in a better understanding of the costs involved in employing fuel modification or emission control hardware relative to the costs of increased ventilation which mpy be necessary to maintain a safe working environment for the underground worker."

Jan 1, 1981

By L. C. Bird, N. T. L. Landgren, M. W. Mikhail

"Through funds made available in 1972 by the Nova Scotia Department of Mines and Energy (DME) and the federal Department of Regional Economic Expansion, a program was initiated to recover saleable coal from mine waste dumps adjacent to the existing Acadia wash plant in Stellarton, Nova Scotia.Following evaluation of these dumps in 1972, the Acadia wash plant was modified to treat high-ash material. The first production was recorded in late 1974. By the end of 1979, a total of 738,202 t of dump material had been processed, yielding a total of 205,212 t of thermal-quality coal.The successful Stellarton operation led to considering the possibility of recovering thermal coal from other dumps. Evaluation of the Westville dumps indicated total recoverable reserves of 1,346,617 t averaging 53.8OJo ash.Parameters for plant design were defined from the washability characteristics of the dump material and the results of a bulk test. Two options were proposed; one was to use the existing plant with some modifications, the other was to build a modular mobile plant that could be used at future dump sites in the province after Westville. At the 25% ash level, the potential recovery of coal from the dump was estimated at 41% yield (by weight) or 549,679 t."

Jan 1, 1981

By Edgar A. Manker

"Today's market for columbium has only developed in the last two decades, and in this sense it is ""newer"" than molybdenum, vanadium and most other steel alloying elements. In this short period, it has assumed a very important role in steel alloying and in superalloys. From a few hundred thousand pounds of columbium in 1960, consumption has grown to nearly 30 million pounds per year, with a market value approaching two hundred million dollars.To assess the outlook for columbium, we will first consider the historical development of consumption and supply, particularly noting that all of today's major mines were developed during the last two decades. From current production, we will attempt to reasonably project the future. This future may well include new producers, particularly some producing columbium as a co-product with tantalum.The growth of current applications, and emerging new applications, will be considered with regard to future consumption and in relation to future trends in pricing.IntroductionThe nineteenth century was a busy time for the discovery and naming of new elements. Among those discovered were columbium in 1801 and niobium in 1844. Although it was later shown that columbium and niobium are the same element, the two names are still used today. Niobium has been pronounced the ""official"" name by the International Union of Pure and Applied Chemistry, but columbium is still widely used in commercial practice, and we have chosen to use columbium in this paper."

Jan 1, 1981

By M. P. Brameld, G. Archambault, R. H. McCorkell

"The rates. J. at which materials emit radon are of interest in studies of the sources of radon in mines. buildings. soils overburden and other places where it may indicate the location of ore or be a health hazard. Here J values were determined by measuring the radon concentrations by means of scintillation counters or alpha-particle track detectors in chambers in which specimens were sealed. Errors in the measurements due to leakage from the chambers. lack of secular equilibrium in the decay series of the radon measured, or the limited rate of diffusion of radon from powders or within the chambers were shown to be insignificant or could be corrected. Scintillation counter measurements are highly reproducible; track detector measurements also appear useable and may be made on many small samples using small, simple chambers. J measurements were made for uranium ores, drill cores, standard CANMET pulps. concrete and gypsum board. Powdering of ores had little effect on their J values.IntroductionIn the mining and mineral sciences, radon (222Rn) is of interest chiefly for two reasons: in geochemical exploration for mineral deposits its presence in soil. overburden and water in more than background concentrations may indicate the existence and locations of uranium deposits and, if present in sufficient concentrations, it is a possible health hazard in mines, mills and other places where people live and work. The latter aspect of radon's role has received considerable attention recently(1,2,3,4,5), and surveys of soil-gas radon concentrations have been used for some time in searches for uranium deposits(6,7,8,9,)."

Jan 1, 1981

By I. R. Ward

"The need for energy conservation has been of increasing concern since the early 1970's, when the cost of petroleum based energy began to escalate rapidly and security of supply became uncertain. The cost of energy from alternative sources has also increased due to development costs and environmental restrictions.These developments have had a serious impact on the mining industry, which is energy intensive. The impact is magnified as lower grade ores are treated, and more energy is consumed per unit of product. In many cases increased operating cost is not compensated by the rise in product selling price.The magnitude of energy consumption in the mining industry is indicated by recent studies conducted in the U.S.A. and Canada. Based on 1970 figures, it was reported that the production of 1 ton of copper in the U.S.A. required 111. 8 x 106 BTU of energy, of which 60. 7 x 106 BTU (54.3%) was consumed in mining and processing (l)The survey of Canadian mills, conducted by CANMET and reported to the CMP meeting of 1978 (2), showed the following milling energy consumption figures (approximate averages):"

Jan 1, 1981

By J. G. Strasser

"There has been considerable output over the last three decades from the social sciences concerning man and his working environment. In the mining industry at large, however, authoritarian, hierarchical control systems remain the norm, and it can be argued that something less than optimum effectiveness in terms of both productivity and worker satisfaction has resulted.Recently (/975), Campbell Chibougamau Mines Ltd. devised a most interesting organization and incentive system that links the underground production of a standard ton of mined output at controlled grade to an incentive payment scheme. A parallel scheme in the mill complex is based on maximizing recovery of copper and gold from available feed. A key part of both minsystems is the formation of groups who have considerable autonomy, particularly when compared to the still prevalent traditional mining industry relationships between the worker and supervisory levels.This paper traces the development of Campbell Chibougamau's system . Attention is drawn to qualitative and quantitative measures of the success of the method through the commentary of those miners involved in the scheme, and by reference to the favourable records on productivity, absenteeism, safety, turnover and grievance activity.IntroductionPyramidal or hierarchical management control systems, coupled to piece-work incentive schemes, predominate throughout Canada's underground mining industry. Although specific details of such systems vary from site to site, they , are generally understood and accepted as fact by the majority of the work force.Normally, a front-line supervisor (shift boss) directs a number of workmen and assigns them to tasks and working locations commensurate with their abilities, knowledge, training and skills. This front -line supervisor may direct or supervise from as few as 12 to as many as 75 or more workmen. He issues orders according to his assigned production objectives and ensures that these directions are fulfilled in accordance with standard mine practice . Several shift bosses are usually directed by a mine foreman or mine captain. The mine captains report to a general foreman or directly to the mine superintendent or his assistant, depending on the size and scope of the operation."

Jan 1, 1981

By James F. Kelly

"Research and development on the production of liquid fuels from coal is rapidly expanding worldwide. AImost every industrialized country is engaged in coal liquefaction research and process development. In Canada, the federal government, through CANMET, is actively supporting coal liquefaction research and development in a number of areas.A review of the basic principles and some of the processes in the production of liquid fuels from coal is presented with reference to the characteristics of the Canadian coal resource base. An overview of the CANMET coal liquefaction contract program is presented and specific results from the batch autoclave studies carried out with Saskatchewan lignite and Nova Scotia high-volatile bituminous coals are discussed. The development of a laboratory-scale continuous-flow coal liquefaction unit at the Energy Research Laboratories of CANMET to investigate the co-processing of coal and bitumen/heavy oil is also described.IntroductionThe CANMET coal liquefaction program is made up of two interrelated parts. The first part consists of the research and development work being carried out at the Energy Research Laboratories near Ottawa, Ontario. The second focuses on contracted research and development as part of the Coal Conversion Program of Energy, Mines and Resources Canada. The long-term objective of the liquefaction program is to contribute to Canadian liquid fuels production through the definition, research, development and demonstration of different coal liquefaction technologies for the Canadian marketplace.In coal liquefaction, the main objective is to produce liquid hydrocarbons with a higher hydrogen-to-carbon (HIC) ratio than the coal feedstock while reducing heteroatom (S,O,N) content, removing mineral matter and minimizing gas production. Typical atomic HIC ratios for a variety of Canadian fossil fuels are shown in Figure I. Canadian coals have about 500/0 of the HIC ratio present in tar sand bitumens and heavy oils and only about 20% of the ratio available in methane. In general, the cost of synthetic fuels production is related to the cost of hydrogen and, therefore, to the increase of HIC ratio between feedstock and products. On this basis, the production of liquid fuels from coal would be expected to be more costly than liquid fuels produced from bitumens and heavy oils. However, for mined tar sands and some heavy oils this difference tends to be offset by the large sand content (>90 mass %) of tar sand bitumens and the increased production costs of viscous heavy oils. For example, it can easily be shown that for equal weights of distillate <525°C) yield, current coal liquefaction processes required between two and three times less mined coal by weight than the mined tar sand s required for the most technically advanced processes proposed for bitumen upgrading."

Jan 1, 1981

By W. Evans, C. E. Ells

Nuclear power reactors using zirconium alloy pressure tubes generate electricity in several countries. Such reactors are particularly important in Ontario, where CANDUs* generate about 30% of the total electricity produced in the Province. Starting with the commitment of NPD-2 in 1956, the pressure tubes of the first five CANDU reactors were made of coldworked Zircaloy-Z, an alloy of Zr and Sn. This alloy was developed by the US Navy, but the decision to use it in a cold-worked condition was based on AECL work. In 1958, the USSR published information on a new alloy, Zr-2.5 wt% Nb. The Nb promotes stabilization of the (3-phase in the material, thus presenting opportunities of exploiting metallurgically strong pressure tubes analogous to the heat-treatable cx-{3 titanium alloys. After construction of two reactors using Zr-2.5 wt% Nb in a quenched and aged condition, an extensive development program on cold-worked Zr-2.5 wt% Nb pressure tubes resulted in them becoming the reference tubes for all CANDU reactors committed since 1966. Anticipating the future needs of the domestic and export markets, AECL have pressure tubes of Zr-3.3 wt% Sn-0.8 wt% Nb-0.8 wt% Mo (Excel) in an advanced state of development. These tubes will be used in an annealed condition; our projections show that they will have improved dimensional stability over the lifetime of the reactors. These improvements result from experimental programs leading to an understanding of the relationship between microstructures and fabrication variables and effects of the environment during service in nuclear reactors.

Jan 1, 1981

By C. A. Rowland

"Plant owners and operators, plant designers and grinding mill manufacturers are giving much attention to the design and manufacture of autogenous and semi-autogenous grinding mills, particularly the mills that have large diameters and draw power up to 10,000 hp and greater. Reliable designs giving long operating lives are required in today &apos;s ore processing plants.This paper reviews bench-scale and pilot-plant testing to determine first if the ore is suitable .to be ground by these methods and then reviews the data obtained from pilot-plant testing that is used to select the mills and the grinding circuit. The paper then discusses the use of the pilot-plant results to design the mills. The most important pilot-plant data used for mill design are power and the amount of ball charge to be used. The mill size selected is a combination of these factors. Pilot-plant data not only establish power requirements, but can be used in the selection of the type of drive, variable speed or fixed speed, and the operating procedure to be followed. This leads into the mill control circuit to be used. The total charge in the mill, the type of drive and mill discharge arrangements are needed in the calculation of stresses and bearing loads. Conclusions reached from pilot-plant work are used to obtain data for process design, and autogenous and semiautogenous mill design should be part of any test program incorporating either or both of these grinding methods."

Jan 1, 1981

By J. W. M. Porritt, K. C. Cheng

Knowledge of radon emanation rates from uranium-bearing rocks is essential to the design of mine ventilation systems for uranium mines. Measurements of equilibrium ratio between radon and its daughters in mine air are important for a better control of mine radiation conditions. The concentrations of radon and daughters were monitored at cut-and-fill stopes in the Beaverlodge Mine of Eldorado Nuclear Ltd. during all phases of the mining cycle. The radon emanation rates of ore and rock samples were measured at the laboratory and the results were compared with in-situ emanation tests in an isolated ore drift. Samples of backfill solution, backfill drainage and ground seepage water were measured [or radon and analyzed for radium and uranium. The results showed that discharges of backfill solution and daily shift-end blasts were the two major sources for a rapid release of radon gas in the ventilation air. Other mining operations, such as drilling, mucking, etc., contributed little effect on radon release to the mining environment. Radon emanation rates of the Beaverlodge are samples ranged from 13 x 10-18 to 600 X 10-18 Ci/cm2/ sec and that of waste rock samples from 0.54 x 10-18 to 13.4 X 10-18 Ci/cm2/sec. The in-situ emanation rate of mine walls with ore-to-rock ratios of 1 to 7 was 60 x 10-18 Ci/cm2/sec. The average equilibrium ratio of radon and its daughters in stapes was 32.6%. Under a normal ventilation condition, the average background levels of radon concentration in cut-and-fill stopes ranged from 13 to 80 pCi/L. The discharges of backfill solution during backfill operations at 100 tons solids per hour released approximately 1.8 x 106 pCi/min of radon and elevated radon concentration in stapes 2 to 5 times above the background levels.

Jan 1, 1981

By T. H. North, A. G. Glover, R. J. Pick

"Girth welding operations represent the rate-limiting step in pipeline construction. A joint industry-university program was set up to establish the field welding characteristics of large-diameter, high-strength line pipe.Theoretical work carried out at the University of Waterloo showed that pipe wall thickness and joint misalignment prior to welding has a marked influence on the lifting stresses acting on the root pass of girth welds. Pipe diameter and pipe ovality had negligible effects. Super-position of lifting and residual stress (caused by the fusion welding operation) highlighted regions of the weld bead most susceptible to hydrogen-induced cracking.The field welding characteristics of 1219-mm-diameter, 13.72-mm-wt Grade 483 line pipe were evaluated using a specially designed test rig. The principal test variables were lift height, delay time after root pass deposition, preheat temperature, pipe composition and joint misalignment prior to welding. For any given life, preheat and joint misalignment prior to welding had the most significant effect on cracking tendency.The output of this program has industrial significance and illustrates the beneficial features of university-industry collaboration.IntroductionField welding operations comprise the rate-limiting step during pipeline construction. Crack-free girth welds must be made in a wide range of weather conditions and consequently the field weldability of line pipe compositions directly affects pipeline integrity and construction economics.Pipe-laying practice comprises root bead deposition followed by a skidding operation involving lifting (or lowering) the pipe length onto skid s so that the next pipe length can be aligned prior to welding. Consider pipeline construction using 24.4-m lengths of 1219-mm-diameter , 13.72-mm-wt Grade 483 pipe weighing approximately 10,000 kg. Skidding involves loading a 3-mm-thick root bead by moving the free end of the pipe through vertical distances of up to 700 mm . The likelihood of cracking in these circumstances depends on the inherent crack susceptibility of the pipe composition employed, on the hydrogen content of the deposited weld metal and on how well the joint handles the external stressing caused byskidding."

Jan 1, 1981

By Brian W. Mackenzie

"This paper briefly outlines the characteristics which should be considered in assessing the economics of mineral exploration, and illustrates such an assessment by using data from the Canadian base metal sector. Implications for the sector are found to include the following:(1) base metal exploration has the potential to create a substantial amount of new wealth;(2) investment incentive for exploration under current conditions is not unattractive over-all;(3) because of existing taxation policies, there is much more incentive for large companies to explore than for smaller enterprises;(4) succesful exploration is sensitive to the size, financial resources and organizational structure of the exploration entity;(5) the general level of recent exploration expenditures should be adequate to maintain the current rate of production and perhaps to support very modest growth; and(6) there is an important opportunity for growth in the sector.The findings of the study suggest that government policies should be made more flexible, in order to take into account the risks associated with exploration and with price fluctuations in the base metal sector. Recommendations are also made concerning improvements in provincial regulations for disclosure of exploration information."

Jan 1, 1981

By Julian Baldry

"This paper begins by describing the parameters of high-speed underground tracked drifting operations and the mucking cycle, and-discusses their variations. The railbound Haggloader 8HR is then described, as well as the Hagglund shuttle trains, outlining the advantages and disadvantages of the system. A comparison with conventional mucking operations is then given.IntroductionDrift and tunnel rounds are mucked by one of two major methods, either trackless with diesel loaders and trucks or with track loaders and cars. The aim of this paper is to compare the conventional tracked mucking cycle with the Hagglunds system alternatives.For many years, the traditional method of attacking the mucking cycle has been with a rocker shovel loader, a string of cars and a locomotive. The rocker shovel loads the first car and when full it is taken to a side drift, cherry picker or some other transfer point and is exchanged for an empty one. This empty car is then pushed back into the face and the loading continues until all cars are full . Then the whole train is taken out to a dump point where the cars are emptied. Normally the train&apos;s capacity is less than the volume of the muckpile, so the cars go back to the face. This loading cycle is repeated until all muck is removed from the heading. The last train out from the heading usually takes the loader and parks it in a side drift before continuing on to the dump where the cars are emptied.This simplified version of the traditional loading cycle excludes the ancillary work elements such as track laying and so on, but does point out that the cars must be transferred when full and that the whole train normally makes at least two round trips from the dump to the face. The prime aim in drifting is to cycle a round whithin a working shift which necessitates that no one part absorbs so much time as to prevent the completion of the cycle.Mucking, drilling and loading and the ancillary work such as rock bolting, vent and service pipe hanging typically each take one-third of the available work time. Drilling or mucking can and often do, because of various factors, take nearly half of the total cycle time. Once any segment of the operation starts to take this portion of the shift, the likelihood of missed rounds becomes increasingly greater."

Jan 1, 1981

By P. S. Daly

"The purpose of this paper is to describe the types of instrumentation used at Sherritt Gordon&apos;s Ruttan Mine to monitor the"" effects of mining. The aim of the monitoring program is to establish parameters to achieve a maximum ore recovery with minimum dilut ion in a safe environment.The copper-zinc Ruttan Mine is in northwestern Manitoba, approximately 760 km from Winnipeg (Fig . I) . Production commenced in 1973 from the open pit at the rate of 10,000 tons per day. Pit bottom lies 58 metres above the first mine level. Underground development has overlapped with open-pit mining throughout. The open pit was phased out in the latter part of 1980.Underground production began in early 1979. The mining method employed in the first lift is sub-level blasthole open stoping with delayed hydraulic filling. Large-diameter (6.5-in.) holes are being drilled in the crop stope area and are also planned for some other areas for vertical retreat mining into a slot. GeologyThe orebody consists of numerous sulphide lenses of variable size, geometry and geology . The lenses occur within volcanoclastic host rocks which exhibit a strong variability in intensity and type of alteration and structural characteristics. Stope design and sequencing were based on these complex geological factors."

Jan 1, 1981

By M. K. Abel

"The Strathcona Mine is located in Levack Township on the North Range ofthe Sudbury Basin. The main orebody consists of pyrrhotite-pentlandite-chalcopyrite mineralization associated with an embayment of the footwall of the Sudbury Irruptive. A zone of massive chalcopyrite-cubanite-pentlandite mineralization occurs in a complex vein system in a series of mixed gneisses and breccias in the footwall. Vein widths vary from a few millimetres to 6 metres. In December 1979, this zone was estimated to contain 976,000 metric tonnes, with a grade of 9.31% Cu and 0.46% Ni. The vein system has a general strike of N 68°W at an angle of 60 degrees to the average strike of the footwall contact of the Irruptive. The dip of the vein system is 45 degrees sw. The strike and dip of individual veins in the system coincide with the directions that would result if a compressive stress had acted in a direction normal to the footwall of the Sudbury Irruptive, producing a conjugate set of fractures. The strike of the Irruptive at the Strathcona Mine is parallel to the long axis of the basin.IntroductionThe Strathcona Mine, owned and operated by Falconbridge Nickel Mines Limited, is located in Levack Township on the northwest rim of the Sudbury basin (Fig. I) . It is one of a group of nickel-copper sulphide ore deposits present along an 8.2-km section of the North Range of the Sudbury Irruptive. In the mines of the North Range, subunits of the Irruptive, going from hanging wall to footwall , include felsic norite, dark norite and dark norite breccia. The footwall complex at Strathcona includes the late granite breccia, which hosts a large proportion of the nickel-copper ores, and a compositionally variable group of brecciated and migmatized rocks, herein referred to as the feldspathic gneiss complex. It is within this latter group of rocks that the vein system of the Copper Zone occurs."

Jan 1, 1981