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By J. A. Reid

THE views and observations expressed herein on this old but constantly recurring question are our own, no effort having been made to align them with standard texts. Therefore, while they may find general acceptance amongst fellow engineers, they must stand as personal opinions and as such are open to debate and discussion. In order properly to consider the subject, it should first be 'set in proper perspective. Why are Prospects Examined? Prospects are examined to determine whether they may contain economic concentrations of metals or minerals, the legitimate mining business being run, pretty largely, to make money. Next to food and clothing, modern civilization is based on metals, with which are included in this discussion minerals, oils, and fuels. A constant and increasing demand for the common metals requires the location of replacements for depleted orebodies, while the use and appreciation of new metals brings increasing demand for them. Aluminium is a good example of a metal which has, within recent years, made great progress. Today, we are becoming increasingly aware of magnesium, chromium, tungsten, thallium, and other lesser known, metals.

Jan 1, 1945

By J. Font

New approaches for the fire refining process of blister copper have been carried out at the Codelco Norte Smelter. These have been mainly focused on modification and improvement of the process configuration based in fluid-dynamic and metallurgical studies of the oxidation and impurity treatment stages. This paper presents the results of the laboratory simulations and industrial tests performed in the 250 t anode furnace, evaluating two different process configurations: ? Bottom Bath Agitation System in the vessel during the oxidation stage, ? Dual Flux Injection System during the impurity treatment stage. The results show the possibilities of effective removal of high content of sulfur from the melt during the oxidation stage by using the bottom bath agitation. The use of the dual injection system demonstrated the significant improvement in the removal efficiency of impurities. Cu2007

Jan 1, 2007

By George P. Demopoulos

In this paper the author will provide an overview of over 20 years of research & developments in the area of hydrometallurgical arsenic immobilization that culminated recently in the industrial implementation of the atmospheric scorodite process. The paper will consider various aspects of arsenic fixation in the non-ferrous metal industry from the iron-arsenic co-precipitation process employed to arsenic-bearing effluent solutions; to autoclave processing of arsenical copper and gold feedstocks and the fate of the in-situ formed iron sulphato-arsenate precipitate phases; the precipitation and stability of scorodite; the possible stabilizing role of mineral phases like yukonite, and the development of "scoroditeplus" processes employing novel encapsulation strategies. Emphasis is placed on the characterization and long-term stability of the various forms of arsenic-immobilized phases under either oxic or anoxic conditions over a wide pH range and the establishment of critical links between process parameters and hazardous material stability, contributing thus to advancement of new generation safe and sustainable waste management technologies.

Jan 1, 2014

By M. Kellner

Due to continuously growing resource demands and increasing requirements for sustainability, safety and environmental protection on the other hand, the mining industry is being subjected to these additional requirements. Over the past few decades progress has been made in all topics. In 1987, the United Nations published the following in the Brundtland Report: ?development that meets the needs of the present without compromising the ability of future generations to meet their own needs.?[5] The term ?Blue Mining? means to work sustainably, economically, ecologically, and efficiently while also improving ergonomics, for example by increasing automation. An example of how mining can actively be involved in energy management will be shown. Initial evaluations of underground cavitites were done for purpose of energy storage. The planning and construction of underground pump storage plants both in active and inactive mining operations was also investigated.

Aug 1, 2013

By G. A. Barclay

"I - INTRODUCTIONSteel castings still comprise the largest volume of wear materials used in crushing and grinding in the Canadian mining industry. The range of impact and wear properties possible with steel castings enables them to be used successfully in both high impact crushing as well as milling where abrasion resistance is the main criterion. Approximately 15,000 tons per year of steel mill liners and crusher castings are used by Canadian mines.The properties of the main steel casting alloys used - manganese, pearlitic chrome-moly and martensitic medium carbon steels will be discussed with reference to their applications. Field data on a new application in primary gyratory crushers for martensitic medium carbon steels is presented. Liner wear life and mill efficiency can be improved through proper liner design.The liner wear pattern can be used as an indication for liner profile changes to improve wear life. Changes in liner configuration can improve through put and use of larger castings can reduce downtime. Casting performance can be improved and foundry production costs reduced by adopting certain design improvements.II - ALLOYS USEDTable I list the most common ferrous liner materials used in relation to their hardness and wear resistance (1). The most wear resistant materials are the irons at the top. In many applications the service impact exceeds the impact strength of the irons and tougher less wear resistant steels must be used. The impact resistance improves from top to bottom with manganese steel the toughest. The hardness of the martensitic steels approaches that of the Ni-Hards however the wear life, because of the absence of carbides, is less."

Jan 1, 1983

By A. Probst, J. A. Finch

"Solids concentration (weight % solids) profiles and the clear liquid/slurry interface level (mud-line) were determined from conductivity measurements in thickeners at Falconbridge's Strathcona mill (Ni concentrate and non-mag thickeners) and Kidd Creek Division (Cu, Zn concentrates and final tails in the concentrator and a jarosite thickener in the Zn plant).The conductivity measurement system consisted of a probe 1.5 m in length with 23 electrode cells, a 24-channel relay, a conductivity meter and a computer. A conductivity profile is collected which locates the mud-line by a sharp change in conductivity. The conductivity measurements are readily converted to solids concentration profiles using a model due to Maxwell.The results from conductivity measurements were compared with direct measurements on local samples obtained using a modified Noranda sampler.It is concluded that the conductivity technique is applicable to locate the mud-line and to estimate the solids concentration profiles in thickeners. This on-line informnation could improve the operational efficiency of industrial thickeners."

Jan 1, 1994

By Chri Langille, Dougal McCreath, Samantha Espley

"In 1993, trials of two innovative applications of liner support involving the replacement of bolts in the ground support system were undertaken at Inco mines. The first trial involved an evaluation of the effect of dynamic loading on mesh-reinforced boltless shotcrete in a sub-level cave mining area on 2400 level at Stobie Mine. The second trial involved an evaluation of the MIROC Mineguard spray-on liner as a replacement for bolts and screen support, or as a replacement for screen support alone, in a topsoil heading of a bulk, VRM (vertical retreat mining) stope on 3240 level at Lower Coleman Mine.In the Stobie Mine trial, an uppers retreat heading was supported using a two-pass system. First, shotcrete was applied 2 inches thick, followed by pinning of mesh screen to the back and walls. A second pass of another 2 inches of shotcrete was then performed. For recovery of the ore zone, a vertical slot was created using a Borepak blind boring machine. The uppers rings were blasted, one or two rings at a time, starting at the slot and retreating out of the heading. During blasting of the production rings, blast monitoring was used to record the ppvs (peak particle velocities). For a series of 5-ring blasts, the maximum ppvs were measured to be 0.4 m/s (16 in./s) with a maximum charge weight per delay of357 kg (800 Ib). Six 5-point convergence measurement stations were set up and after each blast the total rockmass convergence was measured using a tape extensometer. Although a maximum displacement of 100 mm (4 in.) was measured, the shotcrete still managed to provide some support junction. A support damage assessment was also done to try and relate blast vibration to effectiveness of the mesh reinforced shotcrete liner. This trial demonstrated the effect that blasting has, on a support system, and it also demonstrated the necessity of having the mesh reinforcement properly placed within the shotcrete."

Jan 1, 1995

By Akira Miura, Katsuyuki Sato, Yuken Fukano

JX Nippon Mining and Metals Corporation has developed the JX Iodine Process, which is an innovative and patented copper-leaching process for low-grade primary sulfide ores. This process consists of the irrigation of ferric iron and a low concentration of iodide solutions. One-meter column leaching tests were conducted on ore samples from two different mines. At the end of experiments, the total copper recovery exceeded 70% for Sample A and 50% for Sample B with the iodine method, which was significantly higher than that with conventional ferric leaching of 14% for Sample A and 20% for Sample B. To elucidate the reason for the JX Iodine Process effectiveness, cross sections of leached residues were studied. Reaction products were confirmed around chalcopyrite even in the central area of particles in Sample A, however, reaction products were recognized at a depth of only 1 mm from the ore rim in Sample The resistance of Sample A to the leachate appeared to be lower than that of Sample B because Sample A had a high permeability and porosity, whereas Sample B had been affected strongly by a potassium alteration. No reaction products were visible on conventional leaching samples, even at the ore surfaces. INTRODUCTION Hydrometallurgical copper leaching (heap leaching or dump leaching) has been used extensively for copper recovery from oxide and secondary-sulfide ores, but not for primary copper sulfides, which contain mainly chalcopyrite as copper minerals. Although they are major resources of copper, primary copper sulfides are difficult to process because of their refractory nature. Extensive leaching studies have been carried out to leach primary copper sulfides (chalcopyrite), including biological and chemical, using a variety of oxidants and additives to enhance copper recovery. Watling (2013) reviewed acid-chloride-oxidizing agents with chalcopyrite. Abdollahi et al. (2015) tested silver as a catalyst for bioleaching with a chalcopyrite-bearing molybdenite concentrate. Hiroyoshi, Miki, Hirajima and Tsunekawa (2000) found a specific redox-potential zone for high-speed chalcopyrite leaching by controlling the ratio of ferric and ferrous iron. However, no ambient-temperature economic process has been developed for leaching primary copper sulfide, which usually has a low copper grade.

Jan 1, 2019

By D. Mark Richards

Highland Valley Copper is a large open pit copper mine in the southern interior of British Columbia. Machine guidance technology using the Global Positioning System (GPS), was first implemented at the mine in late 1996 for blast hole drill navigation. The purchase of a third BE49R drill in 1998 completed the change to GPS navigation for all the mine?s drilling. The acceptance of this technology was almost immediate at both the operator and management levels. With the purchase of a new P&H 2800 shovel in 1997, the opportunity was taken to extend GPS navigation to a shovel. Due to communication restrictions, this was not as successful as envisaged. In late 1999, following a cost benefit analysis, a three-shovel trial of Caterpillar?s Computer Aided Earthmoving System (CAES), was initiated. The trial was successfully concluded in June 2000 and a further two shovels were equipped. Acceptance of this system has been very good at all levels, which has undoubtedly contributed to its success. In September 2000, CAES was extended to the dozer fleet with the purchase of a new track dozer. The CAES equipped dozer is used for pit production and project work. It is planned to extend CAES to the rest of the shovel fleet in 2001, along with a production front-end loader and one or two more track dozers.

May 1, 2001

By D. Mraz

"In certain instances, rocks around underground excavations behave as a plastic mass. This paper offers several solutions to predicting the mode of plastic flow around cavities and designing mining pillars where plastic conditions exist.IntroductionWhen stresses around underground cavities exceed yield limits of the host rock, the material often behaves as a plastic mass. The best example of this phenomenon is the behaviour of salt rocks in deep salt and potash deposits (more than 500 m deep).However, many other soft rocks exhibit similar properties. For example, Jeremic(1) described certain types of coal yielding plastically under high pressure. Alder suggested that granulated rock behaves plastically.The object of this paper is to propose a de sign procedure for mining pillars exhibiting plastic flow due to the combination of rock properties and in-situ stresses.Prandtl(3) mathematically defined a concept of a generalized, perfectly plastic substance, not possessing the property of strain hardening (Fig. I). He had in mind, a solid with a quasi quasi-isotropic , polycrystalline structure having a well defined yield point, and he postulated that its material elements start and continue to deform plastically when the maximum shearing stress ""'MAX"" reaches a sharp limit, dependent on the mean value of the sum of the major and minor principal stresses:"

Jan 1, 1984

By T. Kalliomäki, A. T. Aji, M. Lundström, J. Aromaa

The settling properties of anode slime in copper electrorefining have crucial effect on copper cathode quality. Anode slime settling is affected by electrolyte composition and temperature, electrolyte circulation, and the sizes and density of the slime particles and agglomerates. Typically, the industrial copper electrolytes contain 40–60 g/dm3 Cu2+, 130–220 g/dm3 H2SO4, 0.04–25 g/dm3 Ni2+, 0.005–30 g/dm3 As, and have operating temperature of 55–70°C. In optimal electrorefining process, the settling rate of anode slime is sufficiently high to avoid the risk of getting the slime entrapped in copper cathodes. In this research the settling properties of copper electrorefining bottom slimes, mainly consisting of Cu, Ni, Ag, Se, Pb, As, Bi, Sb and Ba compounds, were studied by settling rate tests. The tests were conducted in water and synthetic electrolytes with known viscosities and densities. In addition, the effect of agglomeration was taken into account – it was observed that breaking the agglomerates which existed in the as-received slimes decreased the particle sizes on average 56–73%, which decreased the settling rate. The results of this study provide detailed information of anode slime settling and thus clarify the conditions causing cathode contamination risks in copper electrorefining. INTRODUCTION Settling rates of Cu-ER anode slimes affect the purity of cathode copper and faster settling rate decreases the contamination risk (Davenport et al., 2002; Shi & Ye, 2013). The settling rates are affected by the properties of anode slime particles (Wills & Napier-Munn, 2011; Aaltonen, 2014; Kiviluoma, Aaltonen, Aromaa, Lundström & Forsén, 2016) as well as viscosity and density of the electrolyte (Davenport, King, Schlesinger, Biswas, & Robinson, 2002; Shi & Ye, 2013). Thus, it is crucial to find out how the viscosity and density affect the settling rates. Small spherical particles with diameter below approximately 50 µm obey Stokes’ law (Equation 1) (Wills & Napier-Munn, 2011). v = gd 2 (ρS – ρF) (18η) -1 (1) where v is terminal velocity (m/s), g acceleration due to gravity (m/s2), d diameter of particle (m), ρS density of particle (kg/m3), ρF density of fluid (kg/m3), and η dynamic viscosity (Pa∙s). The approximate effects of kinematic viscosity (ν = η / ρS), density (ρS) and particle sizes on settling rates defined for small anode slime particles based on Stokes’ law are presented in Figure 1. However, Stokes’ law does not take into account other than spherical shapes, and it is only applicable for small particles. Consequently, the real settling rates of the particles are lower than these (Wills & Napier-Munn, 2011). Moreover, some of the anode slime particles are larger than 50 µm (Aaltonen, 2014).

Jan 1, 2019

By Jean-Luc Beaudoin

"In addition to the actual energy consumed, billing is dependent on the peak load and the power factor. The lower the power factor goes, the higher will be the penalty the consumer pays. The principles of a power factor regulator, the two ways of improving the power factor and methods for calculating the capacitor values required will be described.The rate structure of the utility company is founded on three cornerstones: the energy consumed during a given period of time and two penalties imposed when the power factor is low or the power demand is high. Even though the normal consumption of a customer might be 10 kW, with a peak demand of 20 kW only once a month, the wiring and associated equipment at the input to the customer's plant will have to accommodate this peak demand. The power company has no means of forecasting these demands and cannot therefore provide the additional equipment necessary. So it exacts a penalty, and the customer must take all possible steps to avoid these peak power demands. This can be accomplished by using an automatic peak load regulator which will selectively disconnect the loads which are not essential in the operation of a plant .The principles of such a controller will be described.Principles of power factor regulatorsThe operating principles of a power factor regulator will now be described. It might be asked why the power factor of an electrical installation in a mine, or a factory, should be corrected at all, but there is a simple answer. In addition to the actual energy consumed, the billing is dependent on the peak load and the power factor. The lower the power factor goes, the higher will be the penalty the consumer pays."

Jan 1, 1982

By Chris M. Healey

"The Jasper Gold mine in northern Saskatchewan produced a total mill feed of 140 127 tonnes at an average grade of 19.0 g/t Au. Both diamond drilling and chip samples from underground workings returned extremely high values, up to 12851 g/t (375 oz/T) Au over 0.10 meter from a chip sample. In the presence of such extremely high grades, the accurate estimation of reserves is a major problem.In the first part of this study, production data from the mine were used to evaluate the results of a variety of reserve estimation techniques in this environment. In two out of three cases studied, indicator kriging with assays cut to 342.9 g/t (10 oz/T) gave extremely good results. In the third case, however, indicator kriging gave unacceptable results. Instead, lognormal kriging of uncut data gave the best results.Secondly, from the same database, a number of drill-hole spacings were simulated, and reserves estimated from the simulations. As may be expected, the results of this analysis show increasingly better results with tighter drill-hole spacing. However, even with a 5 m by 5 m spacing the variation from actual grade was quite large. This is not a systematic under- or over-estimation of grade, rather a random scatter of results.The results of this study show very clearly the problems of deriving good estimates of reserves when extremely high-grade samples are encountered. There is a high degree of randomness to this data base, so reserve estimation in this situation will remain a high-risk operation."

Jan 1, 1993

By S. A. J. Hopper

"The Golden Manitou mine is in the northeast quarter of Bourlamaque township, Abitibi county, Quebec. During the summer of 1937 a body of gold-silver-zinc ore was outlined in a series of diamond drill holes located to the west of an old copper-zinc showing in the property of Quebec Manitou Mines, Limited. In 1938, a shaft was sunk and the orebody further explored from levels at depths of 210 and 360 feet.In 1941 the western half of the Quebec Manitou property was acquired by a new company, Golden Manitou Mines, Limited, and the installation of a mining and milling plant was at once undertaken. Milling started in August 1942. The following is a summary of production to December 31, 1946:The orebodies are sulphide replacements in a sericite schist shear zone. They vary in width from 8 feet to 65 feet and range in length up to 850 feet . Much of the ore is of the 'massive sulphides' type . The sulphide minerals in the ore are pyrite and sphalerite with minor quantities of .galena, tennantite, chalcopyrite, and arsenopyrite. Native silver (as wire and leaf silver) has been found in vugs and as coatings along fractures. In one section of the mine a few specks of gold were observed. Spectrographic analysis of ore samples has indicated the presence of zinc silicate."

Jan 1, 1954

By Rachel S. Prudhomme, Michael L. Jeremic

"The consolidation of mine backfill by free zing is a concept which has been under study in the mining engineering laboratories at Laurentian University during the past three years. The proposed underground application of freezing involves the artificial freezing of in-situ backfill by means of a refrigerated brine solution which would be circulated through a circuit off freeze pipes. The most interesting findings to date are: (I) The uniaxial compressive strength off frozen fill is considerably higher than that of cemented fill in a ratio of 20:1 (aggregate to cement), and (2) load deformation characteristics of the frozen fill suggest that a higher ice content results in more brittle failure and that samples which have initially failed can still support up 10 one-half the ultimate load without additional failure.Although at this early stage a derailed economic analysis of the procedure has not been possible, a general evaluation of the costs involved suggests that the method could be competitive with the hydraulic placement of cemented backfill. Results obtained from laboratory investigations indicate that the freezing of backfill is a structurally feasible option .IntroductionGround consolidation by freezing is based on the principle of transformation o f water contained in an aggregate-slurry into ice, which act s as a binding agent between the bulk particles, and which results in the transformation of a granular soil into a ""rock -type"" material. The abrasive nature of the particles enhance s the strength o f the ice by providing internal friction. As a result of this internal friction, the chances of plastic flow of the frozen mass when in a loaded condition are reduced(1). T he strength of a frozen aggregate is al so dependent on the grain shape of the aggregate particles which may or may not promote particle interlocking(2) and on the temperature since, below the freezing point of the water/aggregate mixture, the strength of the frozen mass increase s with decreasing temperatures.In the shaft sinking industry, artificial freezing of loose , unconsolidated soils has been in practice for several decades. Shafts for Saskatchewan 's potash industry have been sun k to depths of 3000 feet by employing artificial freezing to stabilize the Blairmore Formation(3). The common procedure for freezing ground for shaft sinking is summarized as follows(4,5): I) 150 mm diameter bore holes spaced on 1.5 m centres are drilled in a circular pattern with a radius of 1.5 m outside the periphery of the proposed shaft."

Jan 1, 1985

By A. Kozlowski

We present research on cable fault location methods for mines where coal dust and methane explosions are a frequent potential hazard. The methodology and devices for low- and medium voltage cables fault location are well known and applied in classical power distribution networks. They are based on solutions for underground mines with a high risk of explosion. The lack of a safe solution for the location of a fault has contributed to the initiation of a research project by a group of Polish companies. The consortium consists of research institutes (Institute of Innovative Technologies EMAG, Tele and Radio Research Institute, Central Mining Institute GIG-KD ?Barbara?), Silesian University of Technology and a private entrepreneur MARTECH PLUS. Fast and exact determination of fault location is one of the important factors for minimizing power outage time. The lack of technical solutions to obtain measurements in a secure way leads to the use of the methods connected with a high risk of explosion. For example, the application of high energy can lead to arc discharge where there is a fault in insulation, creating the risk of an explosion. Measurements of methane concentration along the analyzed section of the cable reduce the risk; however the shock wave generated by the electric arc may raise coal dust and make an explosive mixture, which is an object of ignition. Low energy methods, like those based on reflection waves, have low sensitivity for high- and medium-resistance faults. This technique has difficulties in joints, which create false echoes. The fundamental problem is to determine the topology of the network using a reflectogram and find anomalies of a different nature ? not only open and short circuit. Included in the scope of the project is an analysis of Polish legal regulations related to fault location and operational work for low- and medium-voltage networks. Two of the methods used on the surface were selected as feasible to implement under explosion hazard conditions. In the process of development of the fault location methodology, installation features characteristic of underground mines were used, namely access to the whole length of a cable. This is the attribute that provides an opportunity to do measurements that are usually not possible for typical surface power nets. To carry out laboratory tests, a dedicated measuring stand with various types of cables was built. The authors describe the principle of operation of the fault locator and the results of the laboratory tests carried out on the cables with built-in damage (prepared for tests). Results of the work will be the basis for the next stage of the project associated with operational analyses of the prototype.

Aug 1, 2013

By P. Mayer

"Determining the correct mechanism of a boiler tube failure is important for the prevention of future tube failures. Proper corrective measures can be undertaken to alleviate the root cause or causes for a failure only when the correct mechanism is known. A mechanism of boiler tube failure is defined as the process which degrades the tube and produces a failure.An expert system package was developed for use by electric utility power plant personnel during investigation into the cause of a boiler tube failure. It is intended to assist their efforts to recognize and identify a basic failure mechanism that can produce the type of boiler tube failure under investigation. The program guides the user to the most likely failure mechanism by asking simple questions, answers which can be obtained by determining the failure location, type of fuel, and from visual inspection of the failed tube. Expert systems are a form of artificial intelligence which imitate the decision-making process of experts.IntroductionBoiler tube failures (BTFs) continue to be the single largest source of forced outages in fossil fired electricity generating stations. Because of this a concentrated effort is being made to minimize boiler tube failure occurrences. Eliminating boiler tube failures could be worth $5 billion a year to the electric power industry(1).The aggressive service environment of fossil-fired boilers is largely the reason for these failures because the combined effects of stress, temperature, corrosion, erosion and vibration cause deterioration of boiler tube material properties and reduction in wall thickness.Determination of the boiler tube failure mechanism is important for the prevention of future problems. The root cause for a failure can be established and proper ameliorative measures taken only when the failure mechanism is identified correctly. The correct identification of failure mechanism is a complex process which may include many individuals and institutions. Technical specialists in metallurgy, chemistry, combustion, and boiler design frequently cooperate with the station staff in a failure investigation . These individuals rely on personal experience and numerous reports , theories, studies, private communications and investigations concerning the different failure modes and mechanisms."

Jan 1, 1990

By Mark Richards

Highland Valley Copper is a large, open-pit copper mine in the southern interior of British Columbia. Reclamation has been in progress on the site since 1987. Some 6,300 hectares will have been disturbed at the end of the mine?s life, the majority of which will eventually be reclaimed. The establishment of vegetation and the development of a self-sustaining vegetative cover are the central components of the mine?s reclamation plan. The present vegetation-monitoring program for the reclaimed area represents a significant commitment of resources and only addresses a small portion of the site each year. In an effort to expand the area surveyed while improving the efficiency of the monitoring, the use of remote sensing is being investigated. Airborne multispectral imagery was acquired in the summer of 2001, and the results of the multispectral classification were compared to ground observations made during the routine 2000 and 2001 monitoring program. A thematic map with 17 vegetation classes was produced. Within the vegetation classes, there was a strong spectral separation between ? dry grasses? and ?legumes? with further separation according to their density. Green biomass could also be quantified remotely across a wide variety of vegetation types. During summer 2002, further aerial imagery was acquired in combination with a targeted ground-truthing program to determine characteristic vegetation types associated with recognized spectral signatures, which can be used in a supervised classification. It is anticipated that after some fine-tuning, it will be possible to shift the ground-sampling effort from areas where the aerial classification confidence is high to more complex areas.

May 1, 2003

By Melissa Whellams

?? What is a social risk assessment (SRA)? ?? Why do a SRA? ?? When do you do a SRA? ?? How do you do a SRA? What is a social risk assessment? ?? SIA vs. SRA ? SIAs determine how a company?s project will affect social/cultural conditions in a region ? SRAs determine how social/cultural conditions will affect the risk profile of a company?s project Social risk context includes: ? review of human rights record ? analysis of conflict situation ? analysis of political climate ? stakeholder identification ? stakeholder concern/interest identification ? And so on?

May 1, 2008

By D. Lauzon, H. de Ruiter

"In 1988a decision was taken to design and install a computerized mine monitoring and control system. This system had to monitor and control all pumping and ventilation underground. The operation of the mine air heating, using waste heat from the mine water and compressors, was to be part of the system. It ultimately also had to interface with the four existing Canadian General Electric Series 3 PLC's which controlled the No .3 shaft loading pockets. Beside operational control and trouble shooting, the system is a valuable tool in energy management and ultimate savings are estimated at $50,000 per year.The final equipment selection was a General Electric Series Six PLC on surface with a total of 17 Series One Plus and Juniors PLC located underground. Data is transferred through a two-pair shielded cable using modems. Both analog and digital functions are being utilized.The basic monitoring and control system was commissioned during 1989and, due to a higher level of technology today, further improvements have been planned for the future. The system was designed by Walter Dow together with Gordon Champion of D.G. Champion Engineering Ltd. of Toronto. Advice for the ventilation part of the project was obtained from Maurice White, Independent Ventilation Consultant.The Ministry of Energy, Mines and Resources and the Ministry of Energy of Ontario approved this project together with the waste heat recovery project to qualify for a grant of$135,000 under the Enerdemo-Canada program.IntroductionThe Macassa mine is a narrow vein gold mine situated about 2 km west of the town of Kirkland Lake in northeast Ontario. The mine has been in continuous operation since 1933 and a total of about 3.0 million ounces have been recovered out of 6.6 million tons of ore ."

Jan 1, 1991