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Research on alternative lixiviants for gold is ongoing; however few people have looked at complete flowsheets. Alternative lixiviants are typically applied at concentrations 50 to 100 times those required for cyanidation. The higher concentrations make lixiviant recycle a vital part of the process. In addition it is no longer feasible to rely on lixiviant destruction to produce lixiviant free clean water for recycle to the comminution circuit. Ausenco has worked with Barrick to integrate reverse osmosis into the thiosulfate RIL processing flowsheet that forms the basis of the plant upgrade currently being constructed at Barrick’s Goldstrike autoclave facility.

Jan 1, 2014

Barrick Gold Corporation is the gold industry leader, with 25 operating mines and a pipeline of large, long-life projects located across five continents, in addition to large land positions on some of the most prolific mineral districts. Barrick's high level of commitment to sustainable economic development and environmental stewardship was recognized by Dow Jones Sustainability Index (DJSI) - World, for the third consecutive year in 2010. The potential for adverse environmental effects from acid rock drainage (ARD) and metals leaching (ML) and their financial implications for Barrick are key considerations in our environmental assessment and business development processes. Barrick's membership in the International Network for Acid Prevention (INAP) reflects the importance of these issues to our business. INAP's development of the Global Acid Rock Drainage (GARD) Guide (a best practices guide for acid rock drainage prevention) provides Barrick with an important tool to assist in the assessment of environmental and financial risks from ARD and ML associated with our planned and ongoing mining operations (INAP, 2009). In this paper we will discuss how Barrick incorporates the GARDGuide and its principles for ARD and ML prediction and prevention in our business development processes and the management of our operations. The GARDGuide serves as a key reference for our project environmental assessments and as a common link between our projects and operations management, consulting specialists, permitting and regulatory authorities and the public. We will discuss how the GARDGuide is being "syndicated" throughout Barrick as a standard of practice and present a case study of how it was used in a recent Barrick Business Development Project.

Jan 1, 2011

By J. Hedderson, J. Starkey, S. Reeves, B. Hilscher

"As ore sorting becomes more common, it is important to quantify its impact on comminution circuits in order to precisely predict its effect on throughput, grind, and mill operating conditions. Since sulphides and other valuable minerals are often softer then the surrounding waste rock, the ore kept by a sorting system is typically softer than the average ore. In order to accurately forecast production, new measurements of hardness need to be performed on the new concentrated mill feed. This paper proposes a methodology to examine this effect quantitatively at an early stage of project development using the SAGDesign test.INTRODUCTION The application of ore sorting in the mining industry is one of the most promising recent technologies with the potential to cause step change in the way concentrators are designed. Most typically, ore sorters are used to sort a given ore flow for grade, either to reject waste from the mill feed, or rescue ore from the waste pile. Ore sorting technologies have been successfully applied at many mining properties in various forms and while the technology has reached or is reaching maturity in other industries, it is still in development in the mining sector. As a result, there is not yet a general consensus on the considerations that need to be made when designing a plant with ore sorting from a feasibility level above and beyond what is commonly performed as best practice. This paper will discuss those considerations and propose a methodology for integrating ore sorting into a comminution circuit at the design phase. Due to the linearly additive nature of the SAGDesign Test results, a “hardness balance” can be developed to estimate the ore hardness which would be measured in any sorting mass split using only two data points. This will allow a design engineer to make more informed decisions as to the most appropriate mass split to select in relation to the incurred operating costs and grinding circuit sizing."

Jan 1, 2019

By M. Djivre, T. Eger, A. Godwin, I. Bhattacherya

Load-haul-dump vehicles (LHDs) are extensively used in underground mining, however, equipment design and operating conditions contribute to restricted operator sight lines. The inability to clearly see people, objects, or hazards around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines, line-of-sight assessments are traditionally completed in the field. However, field methods are unable to evaluate lineof- sight under dynamic operating conditions, and are limited in their ability to provide feedback on the impact of various operator characteristics such as sitting height. Results of this research show computer simulation and virtual reality can be successfully used to evaluate line-of-sight during the operation of LHD vehicles. In order to benefit from virtual reality applications, the work environment, LHD vehicle, and human posture need to be represented as accurately as possible. A computer simulation program with ergonomic analysis features, Classic JACK 3.1, was successfully used. Threedimensional CAD models of LHDs were developed from manufacturer specifications and pictures taken from LHDs currently in use. The LHD models were imported into the JACK environment, a digital human was positioned in the cab of the LHD vehicle, and the vehicle and human were driven over a typical mine route. Real-time feedback in the JACK program was used to identify what the operator could see under different operating conditions. Machine characteristics and operating scenarios resulting in impaired line-of-sight were successfully identified with this method. The JACK program could also provide real-time feedback on the human’s joint forces and torques, strength requirements, postural comfort, and metabolic energy expenditure. As a result, this method could be used to successfully evaluate musculoskeletal injury risk factors along with system design recommendations to improve workplace safety and productivity in any setting. The LHDs evaluated in the JACK software package can also be combined with mine models and imported into other VR software packages (e.g. Blender) in order to enable viewing in Laurentian University’s Virtual Reality Laboratory. The VR models using these packages can be viewed in stereo to provide better appreciation of spatial vision issues.

Jan 1, 2005

By R. H. Sheaphim

THE RECENT and continuing activity in the Boundary district, British Columbia, makes the publication of this paper timely. The following description and discussions are based on two years' experience in the district as Field Manager and Geologist for Attwood Copper Mines, Limited. The Attwood project was organized by Dr. D. F. Kidd to re-examine the Boundary mining camp. Thanks are due to Dr. Kidd, both for his intelligent guidance during the project and for his permission to publish this paper. Much of the data and many of the interpretations presented are credited to the work of, and to discussion with, Dr. W. H. White, Consultant Geologist, who worked for two field seasons on the project. However, the author assumes the responsibility for this presentation. Dr. C. D. A. Dahlstrom worked with the author during the latter stages of the project. His assistance and advice are gratefully acknowledged.

Jan 1, 1956

By Marketa D. Evans

The mining industry has a significant opportunity to capitalize on its past learnings in order to build better social relationships. The industry?s relationship with society is both critical and under pressure. Rising levels of public opposition and social conflict are already having material impacts on operations around the world. Industry has an opportunity to shape the future direction of this social engagement, build public trust and proactively respond to a material risk to operations, but first it needs to better understand the nature of the challenges and the urgency of addressing them.

Aug 1, 2013

By Nicholas J. Welham

"The effect of extended ball milling has been studied for two industrial processes: (1) the processing of metal sulphide concentrates; and (2) the carbothermic reduction of ilmenite to synthetic rutile. The plant concentrates were a gold ore with 128 g/t Au of which 8% was non-refractory and a zinc concentrate with copper impurities.The gold concentrate showed complete dissolution of the gold bearing minerals after milling giving almost complete gold liberation. The zinc concentrate showed almost all of the sulphides had solubilized leaving the gangue and elemental sulphur. A study of pure pyrite and arsenopyrite shows that selective dissolution should be possible by a simple leaching process directly after milling.The milling of ilmenite and coal together results in a temperature decrease of 150°C in the subsequent carbothermic reduction of ilmenite, in addition to improving both the rate of reaction and the selectivity of reduction to rutile. IntroductionAlmost all mineral processing plants use mills for the size reduction of particles prior to physical and chemical processing. When continuing beyond size reduction the energy transferred causes deformation, breakage and realloying of particles giving a steady-state particle size. The breaking also causes increasing damage to the crystal structure by formation of smaller grains giving an increasing number of grain boundaries and increasing crystalline defects due to deformation. The increasing number of grain boundaries and defects leads to increased reactivity, which can be seen directly by a reaction within the mill, or indirectly, via a decrease in the subsequent annealing temperature required for reaction."

Jan 1, 1997

By Ken McIntyre, Trodel Wolf-Dieter

"Sirius Minerals is a UK based fertilizer development company focused on advancing into operation its polyhalite project in North Yorkshire, England. The operation is known as the Woodsmith Mine which has an estimated 2.7 Billion Tonnes of reserves and is currently in the construction phase. DMC Mining Services was selected to carry out the construction of four shafts for the project, a production shaft of 6.75m diameter to a depth of 1594 m, a ventilation shaft of 6.75 m diameter to a depth of 1565 m, and two additional shafts to support the construction of the material transport system (the MTS and Lockwood Beck intermediate) to 360m in depth for servicing the underground conveyor network for transport of product from the mine site to the costal port facilities located at Teasside. This paper will review the status of the project to date and the innovative approaches that DMC is utilizing to ensure a safe and successful shaft sinking project. INTRODUCTION The Woodsmith Mine in North Yorkshire is a Sirius Minerals-owned deep potash and polyhalite mine located near to the hamlet of Sneatonthorpe, Whitby in North Yorkshire, England, approximately 75 km east of York. The area of interest is more than 700 km2. The £3.2 billion project is to develop the Woodsmith Mine to extract polyhalite, and a tunnel system to transport it to a materials handling facility and harbour at Teesside. The site is the world's largest and highest-grade deposit of polyhalite and is expected to produce 20 million tonnes of polyhalite, potash and POLY4 per annum, as well as create over 1,000 direct jobs and many more indirectly. It has the potential to generate over £2 billion of annual exports for the UK. As the project will require mining to be undertaken in the North York Moors National Park, many objections were raised about the mine. Sirius Minerals has gone to great lengths to ensure that the project is sensitive to the local landscape, including: mineshaft head frames that will be positioned below ground to reduce their visual impact; surface buildings will be kept to a minimum; and the entire site will be landscaped and screened by existing woodland to blend in with the surrounding area. The project will also abide by strict environmental limits which govern our activity during the construction phase."

Jan 1, 2019

By Henry C. Knight

A number of improvements in the techniques of budgetary control have been developed in the 1970's. The most significant of these is zero-base budgeting. This procedure is a marked improvement, because it overcomes some of the key weaknesses inherent in most traditional approaches to budgeting. It incorporates techniques and disciplines which improve the quality of both the budgeting effort itself and the documents that most senior managers will need to evaluate. The end result is a budget that establishes and improves cost effectiveness. This budget is based on resource allocations using cost-benefit criteria and on a system of prioritization for making funding choices. Zero-base budgeting is applied only to costs and expenses that are not conducive to control using industrial engineered standards. Therefore, the benefits attributed to zero-base budgeting will only hold true for administrative, selling, exploration, safety, fire protection and overhead, and other indirect types of costs and expenses. It is in this context that the question of its attractiveness for the mining industry is dealt with.

Jan 1, 1978

By E. Y. Carlson

"IN A SHORT PAPER it is impossible to do much more than to list the industrial minerals found in Saskatchewan and to give a brief description of the activity associated with each. I will not attempt to discuss the geology. It is sufficient to say that the settled part of the Province is covered by glacial drift which varies in thickness from a few feet to several hundreds of feet, and that this has hindered the search over much of the Province.CLAYA notable exception to this is the Cypress Hills area in the southwest corner which did not suffer any glacial action and where we find some of the large exposures of Cretaceous clays. In this area, the majority of the deposits are of stone-ware clays which are •an excellent raw material for such products as face brick and sewer pipe. Although the clay cannot be transported over any great distance it is used extensively in Alberta and Saskatchewan in the production of these products."

Jan 1, 1959

By W. R. Gunter

"INTRODUCTIONThis article documents the current non-metallic mineral s resources of Manitoba (Fig. I), and makes comparisons with currently producing deposits in North America and elsewhere in the world. Industrial minerals may lack the glamour of gold, silver or the base metals, but they contributed approximately 20070 to the value of Manitoba's raw materials, and even out-performed our petroleum industry, except during the oil boom of the early eighties (Fig. 2). Values per tonne of industrial commodities can be as high or higher than for base metal ores. Commodity prices (Canadian), listed in the February 1988 issue of Industrial Minerals magazine, are: talc $202.00 - $306.00, sillimanite $427.00; kaolin $69.00 - $270.00; garnet $175.00 - $250.00; and mica $405.00 - $540.00. The prices are converted to Canadian dollars using the prevailing exchange rates of February I, 1988. Some commodities are not sold by weight. Building stone, for example, is sold by the cubic foot. An average rough granite block, 4 ft by 4 ft by 8 ft, is worth approximately $2000 sitting on the quarry 1100r in southeastern Manitoba (Fig. 3).Thus, not all rocks that do not contain sulphides are worthless. Some may be extracted more profitably than either the base or precious-metal bearing varieties.Industrial Mineral CommoditiesThe commodities available in Manitoba are described in two categories: (1) those already in production that have additional development or expansion potential, and (2) those not in production logical information available at this time.Current Industrial Mineral ProductionThe commodities described herein are currently in commercial production in Manitoba (Fig. 4). These mineral products also have good market expansion potential provided additional geological and market research is conducted. The use of company names in reference to sundry products and locations should not be interpreted as specific endorsement by the Government of Manitoba. The numbers following the commodity name refer to Figure 1. that have good development potential on the basis of geo-"

Jan 1, 1989

By P. C. Patnaik

Performance of industrial gas turbine engines in terms of power output, reduced cooling and efficiency have been continuously increasing in parallel with aero gas turbines due to the advances made in the development of new materials, protective thermal barrier coatings (TBCs) and the advanced diagnostics to monitor service induced problems such as hot corrosion, thermal and thermo-mechanical fatigue and other operational issues, Environmental attack (hot corrosion or high temperature oxidation) is a common degradation mode in the hot section of the gas turbine, Hot corrosion occurs when Na or K bearing compounds in the environment or in the fuel combine with other contaminants such as S and Pb or V to form corrosive sulphates or vanadates thus attacking the protective oxide on the turbine airfoil, These problems pose far more threat to new turbine engine materials such as directional solidified, single crystals and ceramic matrix composites (CMCs). The CMCs due to their increased temperature capability, when used in the combustion chamber, are likely to reduce the peak temperatures attained during combustion and therefore provide the benefits of reduced emissions of oxides of C and N, These issues will be reviewed critically and their impact will be assessed on gas turbine lives. With respect to alternate fuels, past experience has shown that utilization of residual oils and coal derived fuels in gas turbines have resulted in complex deposition and corrosion processes, In recent years biomass derived alternate fuels have been used either through a gasification cycle or through direct firing of the biomass derived liquid fuel with a view to reduce Green House Gases (GHGs) and improve the climatic conditions. In both cases, the resulting high temperature corrosion processes (in the presence of alkaloids in the fuel) are also very complex, leading to premature removal of hot section components, Technology solutions mitigating these fundamental problems will be reviewed and solutions presented.

Jan 1, 2005

By R. K. Singhal

"On the mining side the Canadian oil sands industry has become proficient in excavation and disposal of ore and overburden. Nearly twenty years of mining experience is now behind this industry. While local improvements to existing mining systems and practices will continue, it is believed that some further gains in productivity can be achieved by selectively introducing new ideas from other mining and non-mining industries. This type of technology transfer is vital for over-all cost-effective technology enhancement of oil sands mining operations.Discussed in this paper are the issues of mining equipment, equipment sizing, microprocessor and computer based technol¬ogy as applied to mine-wide data management, automation and remote control and a projection of likely mining systems in the year 2000!This paper reviews the ""state-of-the-art"" in selected surface mining systems and attempts to evaluate the forthcoming technology and its application."

Jan 1, 1989

By A. C. Hitchins, C. N. Orssich

The Eagle zone is a gold-bearing, sheeted, quartz vein porphyry deposit hosted by the Cretaceous Dublin Gulch biotite granodiorite stock, located in central Yukon, 50 km north of Mayo. The deposit occurs at the western end of the stock and has been drill tested over a 1000 m by 500 m area, to a depth of 150m. Mineralization consists of 1 cm to 2 Cm wide, parallel, grey and white quartz veins with accessory gold, arsenopyrite, pyrite, pyrrhotite, chalcopyrite, native bismuth, bismuthinite, and scheelite. Vein densities range from two to fifteen veins per metre and average approximately five per metre. The majority of the veins have potassic and or phyllic alteration envelopes. Alteration of the granodiorite becomes pervasive as vein densities increase. Mineralization outside of the Eagle zone, but spatially related to the Dublin Gulch stock, includes: (i) scheelite bearing sheeted quartz vein zones within the east-central portion of the stock; (ii) a swarm of gold-bearing quartz-sulphide veins up to a metre wide in a zone along the northern contact of the stock and extending 7 km further west; (iii) the Mar scheelite skarn located on the south side of the stock; and (iv) cassiterite-bearing breccias located 2 km north of the stock. A geological potential resource of 64.5 Mt tonnes at a grade of 1.03 g/t Au has been estimated for the Eagle zone from widely spaced core and reverse circulation drill holes. Mineralization is open at depth, on strike to the west and beneath the hornfels to the north.

Jan 1, 1995

By Roméo Roussin

"The yearly production from the Asbestos Hill pit is 1,550,000 tons of asbestos ore, with a yield varying between 18 and 20 % . The orebody was exposed at the top of a hill, and initial production started without having to remove any overburden. The projected ratio of barren rock to ore, based on the present orebody, was 2 to 1. However, as it was necessary to push back the upper benches, this ratio has changed to 3 to 1. The final pit will be 2,300 feet long by 1,000 feet at the longest and widest points. The final depth will be 680 ft. A pit slope stability study was carried out and an average wall angle of 60-70 degrees must be maintained. Preshearing of final pit limits will produce good wall stability. Permanent access ramps will be 60 ft wide, with an 8 % maximum grade. Geological conditions and the low rock temperature are the major causes of the operation's drilling and blasting problems."

Jan 1, 1976

By Robin Sheremeta

Fording Greenhills first acquired GPS (Global Positioning System) technology with the commissioning of a GPS-based dispatch system in December 1994. The second exposure to satellite technology came with the conversion of the conventional optical survey system to a high-resolution GPS system in June 1995. In September 1995,a GPS-based grade control system was tested on the largest shovel (Marion 301 — 58 cubic yard).In January 1996, the system was added to all of the cable shovels (2 P&H 2800s). All three applications of GPS at Greenhills are fully operational and producing positive results. This paper will focus on the practical application of GPS in a mining environment and the effect that GPS technology has had on the Greenhills Mine.

Jan 1, 1996

By J. D. Robertson

An in situ water sampling device has been developed to measure biologically-available or “labile” metals in natural waters and effluents. The active mechanism involves the use of a polyacrylamide gel layer to quantitatively control metal transfer to a trace-metal-adsorbing, gel-imbedded resin. Because the resin only adsorbs free metal ions (the gel sampler methodology is a kinetic speciation technique), and because metal bioavailability is related to the free-ion activity, the device provides a direct measure of the biological-availability of metals in the environment sampled. The prototype consists of a layer of ion-permeable polyacrylamide gel which separates the solution to be sampled from an ion exchange resin. Because approximately 90% of the polyacrylamide gel is water, mass transport through the gel is diffusion-controlled, and is therefore well defined. Metal ions are rapidly bound by the resin, creating a steep concentration gradient in the gel. The amount of labile trace metal that accumulates on the resin can be related directly to the concentration of the metal in solution, the exposure time and the molecular diffusion coefficient of the labile species. In addition, the passive nature of this device affords it the potential to address many of the limitations presented by conventional sampling methods, such as sample contamination introduced during collection or filtration and changes in trace metal speciation prior to analysis. Laboratory studies and limited field trials indicate that the sampler behaves as anticipated and illustrate that biologically- available metal concentrations in many environments are a small fraction of the total concentrations and often significantly less than the dissolved concentration. The implications of this on regulatory criteria are discussed. Additional field trials and correlation with bioassays are currently underway.

Jan 1, 2000

By J. P. Morgan, D. B. Stewart

"AbstractLoad-haul-dump machines equipped with. a torque converter and hydraulic pumps have been field tested by means of an engine monitoring instrumentation package. It was found that owing to parasitic losses in the ancillaries and drivetrain, maximum available useable pourer may peak at less than full engine speed. Simple reduction of engine speed may save 15 to 25 percent on fuel consumption, with no significant loss of available power. On some machines, speed reduction will require modification of the torque converter . The cost of this modification, when necessary , would be offset by reductions in exhaust emissions, ventilation requirements, fuel consumption , heat, noise and hydraulic system maintenance, and by increased life of rotating components and filters and machine availability.IntroductionTHE CANADIAN EXPLOSIVES ATMOSPHERES LABORATORY, in conjunction with Deutz Canada Limited, has designed, constructed and field tested a portable instrumentation package. This package monitors diesel engine performance in underground mining machinery by continuously recording engine speed and volumetric fuel delivery. During tests designed to determine the engine load and speed conditions for the various segments which constitute actual underground operation of a Deutz F6L 714-powered 4-yard load-haul-dump machine, it was discovered that an unexpectedly large percentage of the engine power was required to overcome the ancillaries and drivetrain drag (1). That this large component of engine power is functionally related to engine speed rather than the operator's needs was verified by repeat tests of the used 4-yard machine and by testing of a new 5-yard machine powered by a Deutz F 8L 714."

Jan 1, 1977

By Robin Phinney

Certain statements in this presentation may constitute "forward-looking" statements which involve known and unknown risks, uncertainties and other factors which may cause the actual results, pe1formance or achievements of the Corporation, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. When used in this presentation, such statements use such words as "may", "would", "could", "will", "intend", "expect", "believe", "plan", "anticipate", "estimate" and other similar terminology. These statements reflect the Corporation's current expectations regarding future events and operating performance and speak only as of the date of this presentation. Forward-looking statements involve significant risks and uncertainties, should not be read as guarantees of future performance or results, and will not necessa1ily be accurate indications of whether or not such results will be achieved. A number of factors could cause actual results to differ materially from the results discussed in the forward looking statements including, but not limited to, the factors discussed in the Corporation's annual information form filed on March 9, 2011. Actual results could differ materially from those currently anticipated due to a number of factors and risks. These include, but are not limited to, the failure to obtain necessary regulatory approvals, including environmental approval, the failure to secure full project financing, the failure to implement the recommendations set out in the Technical Report, the failure to raise financing to implement the recommendations in the Technical Report, risks associated with the mining industry in general (e.g., operational risks in development, exploration and production; delays or changes in plans with respect to exploration or development projects or capital expenditures; the uncertainty of estimates and projections relating to production, reserves and resources, costs and expenses; and health, safety and environmental risks), decrease in potash prices and exchange rate fluctuations. Although the forward-looking statements contained in this presentation are based upon what management of the Corporation believes are reasonable assumptions, the Corporation cannot assure shareholders that actual results will be consistent with these fonvard-looking statements. These fon\?ard-looking statements are made as of the date of this presentation and are expressly qualified in their entirety by this cautionary statement. Subject to applicable securities laws, the Corporation assumes no obligation to update or revise them to reflect new events or circumstances. This presentation is a market update based on the Corporation's public disclosure and does not form a part of any offer of securities, or constitute a solicitation of any offer to purchase or subscribe for securities. Any purchase of securities in the company should be made solely on the basis of information contained in the Corporation's public record which is available on www.sedar.com .

May 1, 2013

By C. F. Gleeson

"Geochemical stream-sediment reconnaissance can be a useful exploration tool from the point of view of rapidly and cheaply evaluating the mineral potential of an area. This is particularly true of rugged and mountainous areas such as are found in Gaspé. For the past two years, SOQUEM has been carrying out such surveys over favorable geological regions in the Appalachians of northern New Brunswick and Gaspe. To date, about 4,000 square miles of terrain has been systematically covered by reconnaissance geochemistry. Jeeps have been used as a means of transportation in the easily accessible areas and a helicopter equipped with a winch has been used to lower crews into the more difficult-to-reach regions. Such surveys have been successful in finding metallic mineralization which otherwise might not have been detected.Electronic computation of analytical information has been used to construct regional metal maps, rolling mean maps and residual metal maps. These maps have helped in evaluating anomalies, in relating the regional geo-chemistry to the regional geology and in comparing the distribution patterns of metals. To date, some 30,000 stream-sediment samples have been collected from the Gaspe region and analyzed for Cu, Pb, Zn and Mn. These analyses are being subjected to computer analysis."

Jan 1, 1969