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Waste rock extracted from a mine is typically stored nearby on the surface. Such waste rock piles must be designed to ensure their geotechnical and geochemical stability during the mine operation and after closure. The optimal construction of a pile requires detailed planning. Deposition should involve benches of limited height to control the global slope angle, based on the long term factor of safety. It can also be advantageous to compact the top of each bench and to give the surface an outward inclination to control water flow by limiting infiltration and favoring lateral diversion. When part of the waste rock contains reactive minerals, it is also deemed necessary to use selective placement with the non-reactive portion to prevent direct exposure to natural conditions. The construction must be well documented, and include data from the monitoring program. These and related aspects are presented and discussed in the paper.

Aug 1, 2013

By Christian Brits, Bob Blain, Lloyd Buckingham, Juliu Stieger, Jean-Francoi Dupont

Barrick Gold Corporation (Barrick) has undertaken innovative methods of evaluating and improving the performance of grinding mills in several of its operations around the world. The results have been positive with some of the mines showing more than 20% net energy improvement leading to more than 43,000 tonnes per year reduction in CO2 emissions in four of the operations reviewed.

Jan 1, 2012

By Tomoya Kawasaki, Tatsuya Motomura, Yutaka Yasuda

Saganoseki Smelter, one of the largest copper producers in Japan, currently operates a single flash smelting furnace to produce 450,000 tons of new copper annually. The smelter used to employ two flash furnaces, and integrated the two into one in 1996. Since then, various improvements to its facilities and technologies have been made to increase productivity. To upgrade the operation efficiency, "stability" was considered a key issue, and the measures were taken to increase the operation and facility reliability. Currently, the furnace is running at a feed rate of 215 DMT/h, while the furnace utilization has been maintained at 97%. This paper outlines recent improvements that have made to increase furnace productivity and efficiency.

Jan 1, 2014

By D. C. McKechnie

To the examining engineer, the ever-recurring problem involving the valuation of ore in a prospect presents at different times highly divergent aspects- some entirely physical or mathematical, others essentially personal. The majority of the problems discussed in this paper are obvious to the engineer, and need little elaboration. By the prospector and the general public, however, a number of these questions are often and completely over-looked, or else approached in such a way as to produce final results which are, to say the least, misleading and at times decidedly erroneous. While the purpose of this paper is to deal with prospects or potential mines, many of the problems considered apply equally well to mines with developed ore reserves. As the usual showings on a prospect consist chiefly of a few open-cuts and a limited amount of underground development work, an estimation of the actual ore reserves is a question of minor import, and seldom enters appreciably into an estimation of the probable value of the particular property. The physical valuation of a prospect mainly involves the consideration of such subjects as the general geological features exposed, the strength and type of mineralization, the width and persistence of any associated veins, shear zones, fractures or contact zones, together with the possible grade, size, and continuity of any ore-bodies that may there occur.

Jan 1, 1930

By Kevin Bell

About Beltek Inc. For more than a decade Beltek, Inc. has been working with national and international organizations to harness and deliver solutions which gain real ebusiness advantages in today's world. Our objectives are to partner with our customers to achieve maximum results, while reducing costs. At Beltek, we provide a commitment to you and your organization's needs. Whether that be delivered by ensuring our services and products are state of the art or by providing a level of personalized service, which makes you feel like the center of attention, Beltek is about adding value to every job we work on. The individuals who work at Beltek quickly become your friends because we share your passion and enthusiasm for the business we are in. That's why every person is a leader in his or her respective fields. Having these individuals as apart of our business ensures you get the best out of our equipment, receive the very latest in advise, problem solving and support. We also pride ourselves on our ability to remain flexible at all times because we know deadlines and schedules can change quickly, so we always go the extra mile to deliver exactly what you need.

May 1, 2004

Fatalities Incident Four people perished May 15 ? 17, 2006 ??Doug Erickson ??Bob Newcombe ??Kim Weitzel ??Shawn Currie Incident details available at: ??http://www.mediaroom.gov.bc.ca/sullivan_mine/ ??sullivan_mine.htm Outline Immediate facts/observations from incident ?? #1 Shaft Waste Dump closure program ?? Technical investigations under Panel guidance ?? Findings to date and direction ?? Broaden awareness of potential risks

May 1, 2008

By Shugang Li

Coal and coal-bed methane are valuable energy resources. If they can be extracted simultaneously and safely, the triple purposes of mine safety production, new energy resource supply and environmental protection can be fulfilled. After mining, the mining induced fissure distribution feature and methane delivery behavior in overlying strata were closely related to the relieved methane degasification. Using physical simulation and numerical simulation, it was explained that the distribution feature of mining induced fissure was the Elliptic Paraboloid Zone (EPZ) in three-dimensional space. Based on the key stratum theory, the types, parameters, characteristics and dynamic evolution behavior of the mining induced fissure EPZ were analyzed. Applying environmental fluid mechanics and the mass transfer theory, the relieved methane floating-diffusion equation of the EPZ was established, and the corresponding transport process was analyzed. Using the field practice of relieved methane degasification in Tianchi Coal Mine, it explained that the mining induced fissure EPZ was the storage and delivery area of relieved methane. The degasification effect will thus be useful if the drainage system is laid in the EPZ. Such studies can provide the theoretical basis and technical support for the safe simultaneous extraction of coal and methane.

Aug 1, 2013

By G. Goodall, D. Mercier, M. Brochu, C. Kaplin

A nanostructured CoNiCrAlY coating was obtained by thermally spraying cryomilled feedstock powder using the high-velocity oxy-fuel (HVOF) process. The oxidation behavior of the nanostructured powder and coating were compared to their conventional counterparts by performing static oxidation tests at 1000°C for durations ranging from 1 to 96 hours. It has been found that oxidation of the conventional powder yielded a duplex oxide scale composed of an inner layer of Al2O3 and an outer layer composed of Cr2O3, NiAl2O4 and other spinels. Interestingly, oxidation of the as-sprayed nanostructured coating yielded a similar duplex oxide scale while oxidation of the polished coating resulted in a single Al2O3 layer. These findings indicated that surface oxide seeds act as nucleation sites for the growth of the mixed oxide layer. Also, it was determined that nanostructuring of the coating promotes the nucleation and growth of a single and adherent a-Al2O3 layer by increasing both the number of diffusion channels and the aluminum concentration at grain boundaries.

Jan 1, 2010

By J. Shanks

In 1920 the writer presented some notes, embodying his experience with storage-battery locomotives as main under-ground haulage-motors at Brazeau collieries. (1) Since that date these motors have stood up well to the test of maximum output and heavy overloads, having accomplished all that was expected of them. The notes presented in 1920 gave a brief description of the conditions under which these motors were working at Brazeau collieries, also the cost, per ton mile, of operating them. The cost per ton mile has since then been appreciably reduced, by working the locomotives nearly to capacity and under more ideal haulage conditions, on both shifts. It is not the intention of the writer to repeat what was written in 1920, but rather to give members the benefit of his experience in operating different types or designs of locomotives; to draw their attention to the drawbacks of some designs, and to the improvements made in some of the more recent storage-battery locomotives put on the market, as regards efficiency, upkeep, and safety. Because of their flexibility storage-battery locomotives have advantages over any other type of haulage, where grades are suitable to their use. The number in use in the mines in the United States has increased enormously during the past few years, and this method of haulage is, at the present time, attracting the attention of British and Continental mining engineers.

Jan 1, 1924

By J. R. Gill

Introduction The property and plant of the Falconbridge Nickel Mines, Limited, is situated about 13 miles northeast from Sudbury, in Falconbridge township, near the eastern extremity of the southern Nickel Range. As early as 1899 or 1900 some work was clone on this property by the late Thos. A. Edison, when a shaft was sunk through 80 feet of overburden to within a few feet of the ore-body. At this point quicksand was encountered, which made it impossible to continue with the equipment at hand. As a result, the activities of the Edison party ceased in this section. There was no further progress until 1915 and 1916, when an extensive diamond-drilling campaign, carried out by the E. J. Longyear Company, located the ore-body that is now being worked. The property was acquired by the present operators in 1928, and in September of that year active mining development was commenced. Features Influencing Design Of Plant Early in 1929 plans were prepared for a smelter and the necessary crushing and sorting plant. In spite of the general trend towards the reverberatory furnace as a smelting unit, it was decided to erect a blast-furnace plant. The limited tonnage to be treated, of course, influenced this decision to a great extent. However, it was known that, with the proper procedure, extremely favourable results, both economic and metallurgical, could be obtained in blast furnace smelting. The possibility of very low slag losses, the simplicity of operation by the elimination of roasting plant, fuel plant, etc., the ability to handle coarse feed, and the lower initial cost, were considered factors in favour of the blast furnace. Notwithstanding the fact that we might be called on to treat a certain amount of concentrate, it appeared that the blast furnace was the proper unit for the contemplated operation.

Jan 1, 1932

By K. Scalise, M. Teixeira, K. C. Kocsis, J. Parrish

"This paper aims to introduce and discuss a newly developed algorithm, which can be uploaded on smart watches and other mobile devices to inform and protect underground personnel working in hot and humid environments. Using this algorithm, the metabolic rate (M) of a worker can be determined in “real-time”. In addition, besides warning signs and alarm signals emitted by the smart watch, the algorithm has the ability to determine work-rest time periods based on the worker’s physiological parameters (e.g. age, height, weight, gender) and the climatic parameters (Td, Tw, flow velocity). This paper also investigates whether a re-designed auxiliary ventilation system can provide appropriate work conditions in the production stopes. INTRODUCTION An underground environment with high temperature and humidity conditions generated from various heat and moisture sources can significantly affect the thermoregulation processes of the human body. This can lead to heat-related illnesses such as heat rash, heat cramps, heat exhaustion, and heat stroke. Heat stroke is a serious illness that carries a high risk of fatality, if the underground workers are not immediately treated and the climatic conditions are not corrected (McPherson, 1993). There are two methods used to control the climatic conditions in underground mines: (1) Using ventilation and cooling systems to reduce the thermal stress on the mine workers, and (2) Reducing the heat transferred to the ventilating air from major sources such as: strata, auto-compression, mining equipment, groundwater, blasting, etc. The heat from strata and auto-compression is transferred to the ventilating air at varying degrees, based on factors such as the virgin rock temperature (VRT), the thermal properties of the surrounding rock formations, and the surface air temperature. However, the use of mining equipment and blasting processes can be managed to reduce their contribution to the mines’ overall heat load. To provide appropriate work conditions, selecting the most suitable cooling method depends on the level of heat to be removed, the location of the problem areas, and economic constraints (Brake & Bates, 2002; McPherson, 1993). Because every mine is unique, it is essential to monitor the climatic conditions to select the most appropriate method of cooling. A majority of the time, simply adjusting or re-designing the auxiliary ventilation system can efficiently remove the heat and dilute the contaminants. This may involve moving the ducting system, changing the size of the duct, changing the size of the auxiliary fan, or switching from forcing to an exhausting fan arrangement. If the required air volumes are higher than the existing primary ventilation system can supply, other measures may need to be taken to increase the airflow delivery. This may include regulating the flow in some areas of the mine to increase airflow to the desired area, adding booster fans, or replacing the primary fans."

Jan 1, 2019

By J. Keough

During industrial electrowinning of copper, uneven growth can impact current efficiency, cause short-circuits in the cell and negatively impact the final quality of the metal product. Copper electrodeposits can be made smoother by incorporating a host of additives in the electrolyte but uneven copper growth may still occur due to variations in electrolyte composition throughout the cell-house. To quantify roughness, 3D images of the surface may be combined with scaling analysis to gain further insight into the deposit structure. Moreover, scaling analysis may offer a method to predict long-term deposit structure using short-term copper deposits. In this paper, the application of Atomic Force Microscopy (AFM) and scaling analysis are used to monitor copper growth and extract surface roughness characteristics. The cathode was a 304 stainless steel disc that was polished to a mirror finish. Copper was deposited onto this surface over a range of 10, 20 and 30 minutes from an acidic sulfate solution (40 g/L Cu) at 40oC from an electrolyte that contained or was free of guar. AFM images were acquired to obtain 3D topographical information on the samples and scaling analysis was performed to extract the root-mean-squared (rms) roughness, periodicity (grain size), aspect ratio of surface features and growth mechanism. INTRODUCTION During the process of copper electrowinning, the dissolved metal ions are reduced and thereby deposited onto a cathode substrate which is later recovered by stripping the metal from the cathode surface. Although this process is widely used in the industry, the conditions of the deposition procedure may cause the growth of the metal product to be uneven which can not only impact the current efficiency and final copper product quality but may also lead to plant interruptions through short-circuits if the anode and cathode make contact. To create more uniform copper deposits, a host of additives may be included in the electrolyte which may act as brighteners, leveling agents and inhibitors which may include guar gum, glue, thiourea or polysaccharides or polyacrylamides and their industrial use has changed over time (Moats, Luyima, & Cui, 2015). As such, the electrolyte composition is often complex and subtle variations in the solution matrix throughout the cell-house may impact the surface morphology of the final copper product. In an effort to quantify the roughness of copper samples, image analysis is often applied and may include Scanning Electron Microscopy (SEM) or Atomic Force Microscopy characterization. While both are appropriate, AFM offers 3-dimensional information which may be used to both qualitatively and quantitatively characterize the surface characteristics.

Jan 1, 2019

By M. Bustin, A. Hosseinian, G. Preisig

Hydraulic fracturing and hydraulic shearing techniques are essential for the development of unconventional oil & gas and geothermal resources. Such techniques will also play a key role in the development of CO2 sequestration, and management of high stresses encountered with deep mining. However, the optimal design of hydraulic injections is often limited by continuum treatments of the rock mass without consideration of the influence of the natural fractures present. These may interact with the hydraulic fracture to promote offsets or arrest, or may cause the natural fractures to undergo shear and dilation. Given the limited access to the rock afforded by deep boreholes common to oil & gas and geothermal projects, advanced numerical modeling is critical for understanding key mechanisms and interactions. In this work, we first present a coupled hydromechanical distinct-element model focusing on the propagation of a hydraulic fracture. Normal and shear displacements arising from the generated hydraulic fractures are subsequently integrated into a fracture flow model for detailed analysis of specific flow behaviour and fracture permeability. For this, a scanned 3-D profile of a natural fracture is used to correlate surface roughness to dilation as a function of shearing. Fracture flow is computed at different time steps corresponding to different fracture propagation states and geometries. Modeling results indicate that the opening of a tensile hydraulic fracture is accompanied by millimetre-scale shear displacements associated with slip and wedging between adjacent blocks. This may leads to a mismatch between the upper and lower walls of the fracture if asperities are irregular and strong enough. However, fluid-induced tensile fractures have low Joint Roughness Coefficients (JRC), and associated millimetre-scale shear displacements are too small to ensure a significant offset of asperities that prevent a fully-elastic closure when the hydraulic fracture is depressurized. Injection of proppant is thus critical to keeping hydraulic fracture apertures open. Future work is planned that will see the models calibrated against field data including microseismic event locations, magnitudes and source mechanisms, tiltmeter deformations, stress change, and pore pressures.

Jan 1, 2015

By Marke Wong

? Vietnam?s economy is growing so fast that gross domestic product (GDP) growth remained above 8% in 2005 and exports are rising steadily at 25% per year. ? Demand for electricity is expected to increase 18% per year through 2010 requiring an additional estimated 7,547 MW before 2010 ? Domestic coal demand is expected to be over 45 Mt by 2010. ? The Quang Ninhcoal deposits are estimated at 6.5-7 billion tons (350m) Vietnam News Agency. Saturday, May, 6, 2006. ? National resources are now estimated at 10 billion tonnes; not including a relative new coal bed discovery estimated at 210 billion tonnesin the Red River Basin.

May 1, 2006

By B. D. Pandey, M. S. Kim, B. S. Kim

The recovery of Sn from used Pb-free solder (Sn, 3~4 % Ag, < 0.9 % Cu, < 1.2 % Pb) has been investigated by electrorefining in sulfuric acid solutions containing small amount of hydrochloric acid. This involved preparation of the anode material by melting and casting the used solder followed by refining. During electrorefining, dendritic tin was deposited on stainless steel cathode. Increasing the amount of hydrochloric acid up to 0.3 mol /L in the electrolyte enhanced the current efficiency to 92.2 % and the enrichment ratio of silver to 94.3 % in the anode slime which was otherwise 84.7% and 81.6 % in absence of HCl, respectively. The electrolyte containing hydrochloric acid has also prevented the precipitation of tin oxide in the bath. In the scale-up experiment using 1.6 kg anodes, 84.3 % current efficiency and close to 100 % Ag enrichment ratio were obtained, while the purity of electro-refined tin was over 99.9 %. The energy consumption of the winning process was found to be 0.151 kWh /kg-Sn which is competitive as compared to commercial tin electrorefining processes.

Jan 1, 2014

By Ray Collier

MINING TODAY l EXTENSIVE AND EXPENSIVE PERMITTING PROCESSES WITH UNKNOWN RESULTS l GENERAL AND IMPASSIONED RESISTANCE TO RESOURCE BASED INDUSTRY l SOPHISTICATED, ORGANISED, AND WELL FUNDED OPPOSITION l MOST LOCAL GOVERNMENT DOESN?T WANT MINING TODAY?S TALK l FOUR SPECIFIC OPERATIONS ON WHICH OUR EXPERIENCE IS BASED ? SECHELT ? CADMAN ? GRANVILLE ISLAND ? LEHIGH CEMENT DELTA PLANT l OUR APPROACH TO COMMUNITY RELATIONS

May 1, 2002

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée."

Jan 1, 2017

By Hongpu Kang

The fully mechanized top coal caving mining method has been the main mining approach for thick coal seams with high output and efficiency in Chinese coal mines. The gateroads for the top coal caving mining faces should be driven along the floor of the thick coal seam with a part of the seam as roof. The support of the gateroads is commonly difficult because of the low strength and broken structures of the coal seams, and the increasingly large section of gateroads meeting the need of greater and greater face coal output. Based on the analyses on the geomechanics properties and production conditions of the top coal caving mining, the influences of the top coal caving mining parameters on the stability of gateroads, including mining thickness and face length, are studied. The deformation and damage features of the rock mass surrounding the gateroads with the top coal seam as roof are investigated, the interaction of the support with the surrounding rock mass, the support theory are studied. The bolting design method and criteria, bolting forms and parameters for the gateroads with the top coal as roof are put forward. The rock bolting components, including bolt bars, face plates, cable tendons, meshes, and steel straps, are introduced. Finally, the gateroad bolting effects are evaluated through a typical case study on the basis of field monitoring data, such as the displacement of surrounding rock mass and the forces along bolts and cables.

Aug 1, 2013

DOME MINES, Limited, is a gold producer situated in the Porcupine area of Ontario, 500 miles north of Toronto. During the year 1960, '71 4,600 tons of ore were milled, yielding gold bullion valued at $6,025,370. Prior to conversion to natural gas, an average of 3,200 tons of coal was consumed annually, one third of which was obtained from Canadian sources with the remainder coming from the United States. Due to the distances involved, the freight charges increased the pithead cost by as much as ISO per cent. Steam is generated at a central boiler plant and used for timber treatment, plant heating and process steam. Until August, 1960, steam was supplied during the winter months by two water tube coal-fired boilers, each rated at 200 boiler horsepower at 100 per cent output. Steam requirement was as high as 150 per cent of boiler rating in the colder periods. The summer load was

Jan 1, 1962

By C. E. Lancelle, J. T. Volk, H. F. Wang, D. Fratta

"The Main Injector Neutrino Oscillation Search (MINOS) Near Detector Hall at Fermilab and the Lafarge – Conco Mine are located approximately 100 meters underground in the Galena-Platteville dolomite just below its contact with the overlying Maquoketa shale in Northeastern Illinois, USA. A new cavern was excavated adjacent to the MINOS Near Detector Hall at Fermilab to house the near detector for the Off-axis Neutrino Appearance Experiment (NOvA) program. During this excavation approximately 1150 cubic meters of shale rock were removed. Tiltmeter arrays consisting of a series of hydrostatic leveling sensors (HLS), which are spaced regularly over a total distance of 50-to-100 meters, were used to monitor subsurface deformations. The tiltmeter response in the MINOS Near Detector Hall due to the NOvA cavern excavation is approximately thirteen times the estimated response based on using laboratorydetermined properties. The discrepancy between modeled and measured tilt is likely due to differences in Young’s Modulus in the rock mass versus in a small laboratory sample. Amplitudes of measured solid earth tides differ from the amplitudes of theoretical solid earth tides by up to 40 percent for both arrays. This is likely due to a local heterogeneity or discontinuity.INTRODUCTIONLong baseline tiltmeters have been used to record small earth movements since the early 1900s. One of the first studies using long baseline tiltmeters to measure earth tides was published by Michelson (1914). He used a leveled 152-meter long, 0.15-meter diameter tube half-filled with water connecting two concrete-lined pits. The pipe was trenched 1.75 meters underground in Williams Bay, Wisconsin in a sandy-clay soil. Initially only an east-west line was used, though a north-south line was added after it was seen that viable results were obtained. Measurements were made by hand either hourly or once every two hours depending on the time of day. When compared to 0.7 times the calculated earth tides, the tiltmeter signal matched almost exactly. This excellent result began the use of long baseline tiltmeters to measure small earth movements."

Jan 1, 2015