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By S. Litke

Elemental sulfur was stockpiled at the Mount Polley Mine for use as a source of sulfuric acid as part of research into leaching copper from oxide ores, but the project did not proceed beyond an initial pilot- scale evaluation. Since placement, the sulfur has oxidized and some sulfuric acid leached into the underlying rock. The reaction of the acid with these underlying materials has been studied as part of an evaluation of the effects of leachate from the pile. The rock underneath the sulfur pile is composed dominantly of primary and secondary alumino-silicates with less than 1% carbonate (calcite) and iron sulfide (pyrite). In its unaltered condition, the rock is classified as non-acid generating. Conceptually, it was expected the sulfuric acid would be neutralized by the rock to varying degrees resulting in a series of pH-controlled weathering fronts progressing from leached near the contact with the sulfur pile (pH <3), to active neutralization by silicates (pH 4–5), to active neutralization by carbonates (pH >7). The rocks underneath the pile were sampled to determine the extent to which the rocks had reacted and their long-term stability after removal of the acid source. INTRODUCTION When rock is blasted and excavated to facilitate mining ore, it is typically placed and stored on the surface in piles. The resulting drainage may have a neutral to basic pH (i.e., non-acidic drainage) or a low pH (i.e., acid rock drainage, ARD) depending on the mineralogy of the rock being stored in the piles. Acid- base accounting (ABA) can be used to characterise the two types of rock: potentially acidic drainage generating (PAG) and not potentially acidic drainage generating (NAG) (Price, 2009). According to Price (2009), NAG is defined as having an excess of neutralization potential (NP) in the rock in the form of calcium carbonate-like minerals when compared to acid potential (AP), i.e., a Neutralization Potential Ratio (NP/AP = NPR) greater than 2.0, whereas PAG is classified as having an excess of AP (i.e., an NPR less than 1.0). This is a conservative estimate and may be slightly modified depending on the mineralogy at specific mine sites. Rock with an NPR of 1–2 is also capable of generating acid (Price, 2009) and, depending on the mineralogy, may also be classified as PAG. Drainage from PAG material can generate acid immediately, or many years after it has been exposed to surface conditions. Disposal techniques depend on the category (i.e., NAG or PAG) and reactivity of the rock stored in the piles.

Jan 1, 2019

By Ben R. Bjorkman

The future is here ? or at least that?s what Mine Planners predicted some 15 years ago ? that by 2004 we would have man-less mines running themselves using space-aged technology. Truthfully, though, there hasn?t been much change in mining methods in the past decade, but thankfully that?s all about to change. The benefits of autonomous ? even Tele-operated mining (especially in narrow-vein ore bodies) are wellknown: increased production hours by eliminating travel time to and from the face, continuous production at the face while crews screen and bolt behind the working equipment, less liability for workers? safety in certain areas, etc. But when plans are put in place to accomplish this vision, things stagnate and production carries on as before. This paper examines the components necessary to make that vision a reality. First we?ll detail the technology required to enable Tele-operation ? even autonomous operation of mining machinery, then we?ll look at what?s wrong with the current way we?re mining, and finally conclude with a critique of the machinery itself.

Oct 1, 2004

By G. F. MacDonnell

THE Privateer mine consists of a group of mineral claims situated in the Zeballos area, on the west coast of Vancouver island, approximately 180 miles north of Victoria. Although Zeballos is a comparatively new mining camp, its transportation facilities can be considered exceptionally good. General freight and supplies are brought in by either C.P.R. or Frank Waterhouse steamers from either Victoria or Vancouver. Service by these boats varies from five to ten days and the trip from Victoria takes approximately two days. Passengers may use the C.P.R. boats, or, if speed is essential, they may fly, in which case they have the choice of two flying companies, namely, Canadian Air-ways, Limited, and Ginger Coote Airways. The average flight from Vancouver takes approximately two hours. Excellent unloading facilities are provided at the beach by a government dock for the steamers and a floating dock for aeroplanes. The mine, which is approximately five miles from the beach, is serviced by a fairly good gravel road, which has proved satisfactory for all haulage purposes. Zeballos has the reputation of having one of the heaviest rainfalls on the west coast, but as no accurate records have been kept, no comparisons can be made. H. C. Gunning, in his report, comments on the weather from 1929 to 1932, and one would judge that the practically continuous rainfall did not add to the pleasures of the field work. During the summer of 1938, the opposite condition prevailed and the area had exceptionally dry and pleasant weather. The snowfall is generally light at the lower elevations, but very heavy higher up. No extreme cold weather is encountered during the winter, which is generally short.

Jan 1, 1939

By J. A. Harle

Introduction When considering power in Alberta, there automatically come to mind ideas of either hydro or thermal generation, leaving in one&apos;s thought an uncertainty as to which one would propose. There is frequently an obvious source of power in some locations on our fastflowing rivers, the major possibilities being described in the report on Surface Water Supply and Water Power of Alberta issued by the Alberta Government in 1948, but it must be realised when reading that report that the sites so described will require extensive geological and other surveys before they can be exploited, and account must be taken also of the transmission distances involved in each instance. From a conservation point of view, where water power can be economically developed and power transmitted to the load centres, this should be done, and our thermal resources should be husbanded for our coming generations, especially if our water resources are falling owing to glacial shrinkage.

Jan 1, 1951

By G. S. Hume

Introduction Core drilling of the bituminous sands of northern Alberta has been carried on by the Mines and Geology Branch, Department of Mines and Resources, under the supervision of the Director, W. B. Timm. This was part of the Dominion Government&apos;s wartime investigations, which included an agreement with Abasand Oils, Limited, for the study of commercial possibilities of obtaining oil from the bituminous sands. The drilling programme, commenced in 1942 by the Consolidated Mining and Smelting Company of Canada, was continued in 1943 and subsequently by Boyles Bros. under contract with the Mines and Geology Branch. Several areas have been investigated and one of these, the Mildred-Ruth Lakes area, &apos; herein described, is of special importance in that it contains a sufficiently rich and large deposit of bituminous sands and bitumen beds to warrant consideration of commercial developments for the production of oil. The Steepbank Area, East Side of Athabaska River The Steepbank area, on the east side of Athabaska river in township 92, about twenty-two miles north of Fort McMurray, was selected for drilling in 1942 because previous investigations by Ells indicated it was one of considerable promise both from the standpoint of having reasonably rich bituminous sands under relatively light overburden and also having an excellent tailing disposal and plant site for large-scale operations in proximity to Athabaska river. The drilling done in 1942 and 1943 was largely exploratory, and, when it was found that the southerly part of township 92 had only low-grade material, closer drilling was done in 1944-45 in the richer, more northerly part.

Jan 1, 1947

By E. Rezazadeh Azar

Dump trucks are the main mean for hauling earth material within and outside of the construction and open-pit mining jobsites. The real-time monitoring of the material transportation trips is beneficial for proactive equipment management, volume estimation, and productivity measurement. The traditional manual observation is tedious, non-real-time, and expensive; therefore remote sensing technologies, namely GPS and RFID, have been employed for this reason. Ordinary construction videos are another costeffective alternative to monitor dirt loading and hauling operations in real-time. A vision-based system has been developed to recognize and count hauling trips. This system has three modules including object detection, tracking, and action recognition. This system processes videos taken from access roads in which it recognizes dump trucks and then tracks them throughout the viewfinder. The action recognition module is designed to reject false alarms and also terminate tracking. This way, the system is able to count the number of hauling trips and also record the time between each trip. Several state of the art computer vision algorithms were employed to develop this system. Some of these algorithms were modified using spatiotemporal information to minimize the inherent errors of the vision-based methods. The experimental results showed considerable performance of the system for practical application in the construction and mining sectors.

Aug 1, 2013

By Abdelkabir Maqsoud

Different management options and rehabilitation strategies are available for mine wastes that produce acid mine drainage (AMD). One of them consists in building a cover with capillary barrier effects (CCBE) on the tailings to limit the availability of oxygen, an essential component of the chemical reactions leading to the generation of AMD. Prior to cover construction, a monitoring strategy must be established to evaluate the response and performance of the cover system. The key parameters to monitor should include matric suction and volumetric water content in the CCBE, oxygen flux (and/or oxygen concentration) through and below the cover, and the main meteorological parameters for the impoundment. In this paper, different techniques available to measure the targeted parameters are described and their main properties are given. Recommendations (based on existing cases) on the location and the number of monitoring stations and on the measurement frequency for each monitored parameter are also proposed.

May 1, 2007

By C. L. Popp

The scope is to address issues confronted by parties in the mining industry such as: Mine planners, survey and engineering departments, field teams and subcontractors. Describing approaches and best practices for assembling a project team to identify and create modeling requirements and to implement beneficial results. 3D Machine Control and Guidance tools continue to reduce project risk and attract quality resources with skill sets new to the earthmoving industry. These tools increase production, reduce rework and help with government permitting.

May 1, 2013

The major factors limiting the establishing of vegetation on the shale and sandstone wastes at Minto are high exchange acidity and low pH (shale pH 4-5, sandstone pH < 4). In the first revegetation program (1967-74), 3.8 million trees were planted without grading on 4,000 acres (red, jack and scots pine and black locust). White dutch and sweet clover, birds-foot trefoil and red top were established in selected areas, and ponds were stocked with brook trout. In the second phase of reclamation, beginning in 1979, a comprehensive plan will be initiated which will allow for forest production, wildlife development and recreational activities.

Jan 1, 1977

By Cale J. Dubois

At Cameco Corporations&apos; Cigar Lake Project, large excavations are developed on the 480 Level and 500 Level must remain stable for at least 15 years to host underground processing infrastructure. Following the successful dewatering of the mine in October 2009, subsequent internal rockmechanics investigations augmented by third party technical investigations; determined that to keep the back of the Water Flush Crusher/Run-of-Mine (WFC/ROMs) excavation stable; required a rehabilitation strategy to mitigate deterioration/deformation of the WFC walls and intersection pillars. The mechanism of failure propagating the movement of the excavation walls is understood to be controlled by the presence of a dominant E-W striking and steeply dipping foliation within a relatively weak and mildly altered rockmass sub-parallel in strike with 14 meters high walls and an intersection span approaching 15 meters. The application of open and resourceful communications between site mining engineers, geologists, contract mining staff, construction management experts, corporate mining and civil engineers, and third party technical experts resulted in a multi-faceted short-term ground support strategy consisting of standard bolting and screening, deep-seated modified-strand cable bolts coupled with heavy gauge mesh straps, rockmass reconditioning using low-pressure grout injection, and horizontal cable-lacing for the intersection pillars applied in lifts using a top-down methodology. The intention of the short-term strategy was to stabilize the excavation so that a long-term structural steel support installation - consisting of composite concrete walls, and arch support applied to the side walls and crown of the back - could be constructed safely. This paper summarizes the evolution of the short and long-term ground support strategy and criteria for the WFC/ROMs excavation developed using elements of civil, mining and hydrogeologic design.

Nov 1, 2011

By G. B. Harris

In recent years, increasing attention has been focused on the hydrometallurgical treatment of base metals feeds, especially nickel laterites and polymetallic sulphides. One approach that has received some attention is the use of high?concentration chloride solutions (brines), which are now showing some promise after initial setbacks. Iron is usually the major component in the base metal feed to such processes, and if physical means cannot be used to remove it, then the iron concentration in the pregnant leach solution is always significant. This paper presents some of the background theory on the hydrolysis of iron in high-strength (>3M) chloride brines, and discusses the roles of temperature, solution concentration and free acidity. It is shown that the system is complex, but that crystalline and readily-filterable hematite can be generated, and that the system has a low energy requirement.

Jan 1, 2006

?Founded in 1969 by the Ruia family ?Diversified global business corporation with a balanced portfolio of assets in the manufacturing and service sectors; $15 Billion revenue in FY 2009-2010 ?Employs 70,000 people worldwide with offices in Asia, Africa, Europe and North America

May 1, 2011

By Elmer Palmer

As part of the Goldcorp Inc growth plan Minera Peñasquito SA de CV has developed its polymetallic deposit with a large ?state of the art? concentrator to process lead and zinc ores. The plant consists of two grinding lines including 38ft diameter SAG mills and 24ft diameter ball mills. During mid to late 2009 concentrator commissioning activities commenced. First concentrates were produced in October 2009 and now the plant is meeting its design basis of 65,000 mtpd per line. This paper describes the design and operational experience to date for its grinding circuit design, together with the recently commissioned HPGR crushing circuit.

Jan 1, 2012

By T. Liu, C. Shi, T. Fu, M. Zhong

Water inrush in coal mines is induced by the imbalance of the groundwater flow field and the engineering geo-mechanics field. Therefore, to prevent water inrush it is important to predict the critical hydraulic pressure of water inrush in coal seam floors. This paper will investigate a method for conducting theoretical forecasting of the critical hydraulic pressure of water inrush in coal seam floors by adopting the combination method of a genetic algorithm-neural network. First, the topology structure of a neural network (NN) based on genetic algorithms (GA) will be determined and then the critical pressure of water inrush in a coal seam floor using the chosen NN will be predicted. Finally, theoretical forecasting results will be compared with actual measurement results to determine the feasibility and applicability of this method.

Jan 1, 2008

By W. R. McClelland

GOLD-BEARING ores, representing many types, are found widely distributed through the Province of British Columbia. They range from those which by their nature may be considered as complex, to those whose mineral characteristics are simple. Those in which the gold is associated with metallic sulphides provide particular milling and metallurgical problems, the solution of which involves not only detailed laboratory investigation but also a careful consideration of economic factors. The location of an ore-body may have a deciding influence on the adoption of a method for the metallurgical treatment. Whether the ore should be treated with the object of recovering the gold as bullion or as a shipping concentrate is often dependent on such topographical considerations as the position of the mine at or near tidewater or within a reasonable overland distance of a smelter. British Columbia is fortunate in having the Trail smelter situated in the southern part of the Province, and the smelter at Tacoma, Washington, is accessible for coastwise traffic. Both of these provide a ready market for most types of gold-bearing concentrate. In order that the results obtained by laboratory tests may give a fair indication of what should follow in mill operation, it is essential that the test sample should represent as closely as possible in mineralogical character and in grade the ore that eventually will constitute the feed to the mill. In the early stages of mine development this consideration is sometimes overlooked and samples of a much higher grade than would be representative of run-of-mine ore are submitted. Flotation tests on such a sample of ore high in sulphides may show a low ratio of concentration, bu.t if the actual run-of-mine ore is lower in sulphides the mill operation will reveal a much higher ratio. The recommendations for treatment based on the results of laboratory tests may have been against concentration, when in actual operation this would be the most suitable method of treatment. Recommendations based on laboratory tests are necessarily from the results of work carried out on the sample submitted, modified only by such other economic or topographical information as may be known to the investigator. This paper deals with a few of the gold ores found in the six mining districts of British Columbia and is based on investigations made in the Ore Dressing and Metallurgical Laboratories of the Mines Branch, Department of Mines, Ottawa.

Jan 1, 1937

By A. Ouellette, E. Nilsson

"Preventative maintenance is a burden for equipment users but a demand from the machine suppliers to ensure performance. Machine availability depends on preventative maintenance being followed.Mining equipment is becoming more and more sophisticated and productive, yet less and less time is available for preventative maintenance. Manufacturers invest in reducing costs, simplifying operating requirements, and lowering maintenance requirements, but it is the users who must invest more heavily in the advanced maintenance systems to keep the units operating.IntroductionPreventative maintenance has been, and still is a key factor in avoiding disturbances in production due to equipment downtime. Manufacturers ask for it in extensive maintenance schedules, check lists, programs, etc. often with a ""threat"" that, if not performed, the machine guarantee will not be valid. Modern mining and construction machinery has become sophisticated, like all other machinery, with elaborate hydraulic, electric and electronic systems and computerized controllers. Maintenance organizations within the mining industry have grown to heavy cost centres just to keep up the availability of the equipment.It is difficult for machine manufacturers to have maintenance programs that suit every user. International suppliers have to deal with different cultures, education levels, environments, organizations, etc. Maintenance programs recommended by manufacturers often do not meet some user&apos;s needs while they are ""overkilling"" to others. Preventative maintenance schemes recommendations of what to do, in what frequency, etc.) usually fit mechanical components in the equipment, e.g. wear measurements, crack indications, lubrication, oil changes, etc. But how does one perform preventative maintenance on huge hydraulic systems, electrical and electronic systems and computers? Failures in these systems usually occur without any warning and are more or less impossible to predict. Another difficulty in creating effective preventative maintenance programs for these kinds of systems is the relatively low volume of mining and construction equipment that is produced per year. For example, although Atlas Copco is one of the largest manufacturers in the world of underground blast hole drilling machines, the company still does not produce more than a few hundred drilling jumbos per year. These are made in more than 10 different models, with different systems and components, and very often are custom adapted to the end user&apos;s requirements."

Jan 1, 1992

By D. Lunt

Telfer bulk concentrates typically contain 8% chalcopyrite, 8% chalcocite, 45% pyrite and 80-120 g/t gold. Although very high copper and gold recoveries can be obtained by subjecting the concentrate to a "conventional" high temperature pressure oxidation step followed by copper recovery by solvent extraction and electrowinning, and cyanidation of the leach residue for gold recovery, the cost of lime required for neutralisation and power for oxygen generation was such that the process was uneconomic in terms of operating costs. The challenge therefore was to develop an alternative flowsheet that maximised copper and gold recovery in which the reagent costs were commercially attractive. An additional objective was to reduce the capital cost so that the overall NPV and IRR values would enhance the economic viability of the total project. Following a series of batch and locked cycle testwork programs, supported by Metsim modelling, it was established that the same high levels of overall copper and gold recoveries can be obtained by use of a novel two-stage split leaching circuit in which the chalcocite component is leached in a low temperature (90-110°C) circuit with the chalcopyrite component treated in a high temperature (220-250°C) circuit. This split circuit has a number of advantages, including minimising the required capacity of the high temperature autoclave, as well as reducing the overall lime consumption and simplifying the total process water balance. The paper outlines the basis for the development of the flowsheet and discusses the integration of the leaching stages into the overall circuit.

Jan 1, 2004

?Podolsky Water treatment plant discharges to Norman North bog which drains into Whistle / Post Creek watershed and into Wanapitei Lake ?Whistle Mine closed and reclaimed but continues to treat and discharge water to Whistle Creek

May 1, 2009

By Eirik Sundvor, Hany Doss, Peter Vogt, Kathleen Crane

"Abstract - In 1989-1990, the SeaMARC II side-looking sonar (11 to 12 kHz) and swath bathymetric system imaged more than 80 000 km2 of the seafloor in the Norwegian-Greenland Sea and southern Arctic Ocean. One of our main goals was to investigate the highly oblique (115°) junction between the Mohns and Knipovich ridges, and to determine, using new morphotectonic data, whether or not this junction is stable or in a state of readjustment. These findings are presented in this paper.Along the northern Mohns Ridge, we observed a highly segmented rift valley undisturbed by transform faults. In contrast to the elevated Reykjanes Ridge, the Mohns Ridge is dominated by deep en echelon fault-bounded troughs, which are bordered by high rift valley volcanoes. These segment boundaries are interpreted to be sites of recent to present volcanic activity, based on their high acoustic reflectivity. The northwestern flank of the Mohns Ridge is marked by shallow quasi-linear ridges parallel to the present orientation of the Mohns Ridge. The orientation and geographic position of these ridges suggest that they were formed at the Mohns Ridge. Only in the northernmost cases are some of these off-axial ridges non-linear. The degree of the non-linearities increases slightly with proximity to the Mohns-Knipovich bend. In addition, because no transform fault was detected between the Mohns and Knipovich ridges, we conclude that the Knipovich Ridge must be obliquely spreading to the NW-SE."

Jan 1, 1999

By A. F. Sirianni

The Peace River iron ore deposit represents the sole source of raw material for an integrated steel industry in Alberta. The ore has proved refractory to beneficiation by a number of techniques. A selective oil-phase agglomeration technique is described. Medium-grade concentrates, analyzing 48-53% Fe and 10-14% SiO2 were obtained with recoveries of about 75% of the total iron. These results appear to represent the optimum possible for this ore body.

Jan 1, 1977