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By Chris Yellowega

The construction and startup of a new mine is a daunting task. To successfully locate, design, build and startup an immense human endeavour like a new mine, takes perseverance, planning, dedication and significant capital. The application of capital requires a thorough evaluation of risk and where that risk is most properly limited to create the risk/return profile. One area of significant capital and thus, significant risk is the selection and maintenance of the very machinery needed to deliver the creation of investor wealth. Albian Sands Energy is the operator of the new Muskeg River Mine located north of Fort McMurray in Alberta?s oilsands. The Muskeg River Mine is owned by a joint venture of three companies: Shell Canada, Chevron Canada Ltd.and Western Oil Sands. The mine is designed to run 400,000 tons per day, 365 days per year. The mine conditions vary from material as hard and of similar consistency to pavement to underfoot conditions as soft as saturated sands. Water cannot be drained below surface conditions, shovel teeth can disappear in less than 24 hours and the primary business is often constructing large civil structures that have little to do with the delivery of ore. The mine starts with the deposit (if it doesn?t exist, nothing else matters), moves into the design, the feasibility study and the approval. The evaluation of risk and the strategies surrounding the control of that risk truly lie after these stages are complete. The strategy and execution stage is where risk is eliminated or accommodated. The point at which the investors money is being spent is the point at which the decisions made cannot be reversed. It is of absolute importance that the execution of the decisions are consistent with the strategy agreed to, lest the investors need to be asked for more money. The key sources of risk identified for the Muskeg River Mine were recruitment of trained and experienced personnel and the delivery of ore to maximize early (<2yr) cash flow. The Muskeg River Mine personnel determined that to minimize risk, personnel would be recruited to operate the mine equipment yet, the requirements for maintaining the equipment would best be held by the manufacturer. The strategy was to obtain the correct equipment for the operation of the mine and leverage the supplier?s expertise to ensure the mine wasn?t training a maintenance organization at the same time as a mining organization. In essence the key strategy for the mine start up and early operation was to leverage the equipment suppliers to maintain and repair the equipment. Albian Sands would maximize the utilization of Maintain And Repair Contract?s.

May 1, 2003

Everybody would agree that a good roadway leads to more efficient haulages by reducing haul times, smoother and safer operation for operator and less wear and tear on tires and equipment, thus improving availability and overall costs efficiency. There is a number of factors that come into play to achieve this especially when developing a mine. Excavations of Ramps and Headings: Operators should follow surveyors and layouts accurately while driving ramps. To maintain constant grades on ramps, which leads to better design control of water and easier grading of roadways. Dips and dives lead to needless over excavations and unnecessary cost and disposal of waste rock. When dressing a ramp some areas may require 2 to 3 feet of material to correct the dips and perfect to constant grade. You may ask yourself, is this all necessary? A small exercise is to follow a loaded haulage truck up ramp. At the first hump, grade change, notice the down shift and notice how far the truck travels to regain the up shift and his speed. The difference is remarkably noticeable when the grade is constant. All this leads to less driveline shock, less horsepower demand, better fuel efficiency and more productivity. Drill & Blast Patterns to control water for Ramp Headings: The drill pattern needs to allow for a ditch. A slight cross fall to form a ditch can easily be done with the lifters. The preferred side of the ditch is always the inside curve of the ramp as it has less tendency to erode roadbed material. On a level, the ditch is dictated by the sump location. A blasted ditch will eliminate water pounding and keep the roadbed dry. Water trapped in roadbed is the major cause of rollout and de-stability of roadbed. If the water is allowed to drain in the middle of the ramp it will cause erosion, movement and loss of fines and an increase in grading intervals.

Feb 1, 2008

By M. Bertrand

Oxalic precipitation is usually applied to process radioactive wastes or to recover actinides from a multicomponent solution. Precipitation reactions being highly sensitive to many operation parameters, the computer simulation appears to be a very effective tool to forecast the evolutions of the system subjected to various operating conditions. This study focuses on the tetravalent uranium oxalate precipitation modelling which combines population balance and hydrodynamics. Both experimental and numerical studies are carried out in order to analyse the reactor design influence on the precipitate characteristics. The simulations taking into account primary nucleation and crystal growth are in agreement with experiments.

Aug 1, 2010

By George McIsaac

This paper discusses the formulation of a linear program with the objective of maximizing the cash flow of the long-term plan of an underground operation. A mine is split into eleven independent ore zones, each characterized by its reserves, required development and mining method. Based on practical considerations, maximum rates are set for each zone?s development and production capacity. As for the total mine plan, a minimum daily production rate is set along with a minimum feed grade to the mill. A maximum number of development metres per day is set based on the equipment and labour available. Proven and probable ore is mined preferentially over possible ore in the early years of the plan. Furthermore, the fixed cost of operating the mine is taken into consideration whenever mining activities take place. Once the linear program is solved, it can be critically reviewed, and unrealistic results can be identified. Some resource allocations constraints can then be changed in certain sectors, and new results can be analysed. What-if scenarios can also be examined, such as determining the impact of hiring a contractor to develop a given sector, or dropping an ore zone completely from the plan.

May 1, 2003

By K. Yoo

Chalcopyrite is the most abundant copper sulfide mineral, which is normally processed using pyrometallurgical methods (i.e., smelting) to produce copper metal. Smelting has several major disadvantages, such as high gas-handling costs, high capital costs, saturation of sulfuric acid market, and inability to treat low-grade concentrates and to recover some by-products, such as zinc, nickel and cobalt. The development of hydrometallurgical processes for chalcopyrite is desirable to overcome the problems of smelting. Because chalcopyrite is refractory, the leaching rate for chalcopyrite is very low. Therefore, increasing the leaching rate has been extensively investigated, both in sulfate and chloride media, as well as in the presence of bacteria. Chloride leaching processes have shown relatively high leaching rates. The mechanism of the chloride leaching process has been investigated, but the behavior of chalcopyrite leaching in chloride solution is not clear. Therefore, the effect of the solution redox potential on the leaching rate of chalcopyrite in chloride solution was investigated. In the present study, leaching experiments were carried out using 0.1 M chloride solutions and the results indicate that high leaching rates of chalcopyrite can be achieved at relatively low solution redox potentials.

Jan 1, 2007

By A. L. Williamson

Bio-mining, the use of micro-organisms to recover elements of interest, is potentially useful for the economic extraction and recovery of ore metals from a variety of ore deposits, including the lowergrade uranium deposits found in the uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario. The metabolism of chemolithotropic bacterium Acidithiobacillus ferrooxidans depends on an ability to derive energy and reducing power from the oxidation of ferrous iron found in a varirty of iron sulphide minerals associated with base, precious metal and uraniferous ores. The characteristics of this bacterium, especially the ability to oxidize both iron and sulphur with an associated high tolerance of low acidity, allow the organism to contribute significantly to bio-mining processes. Under ideal conditions, A. ferrooxidans promotes the oxidation of ferrous iron in low sulphide ore materials, breaking the crystal structure of the ore minerals .releasing protons to the surrounding solutions, thus promoting the dissolution of uranium and rare earth elements, among others. This paper provides an overview of elemental dissolution and release of uranium, rare earth elements and investigates the acid generating potential of the final residues, from a series of environmentally controlled, biologically-mediated uranium ore extraction experiments. The findings will be used to guide in the design of larger scale bio-leaching experiments to further assess the potential for successful bio-mining operations along the Quirke Syncline.

Aug 1, 2010

By G. Vibert Douglas

IN a previous paper by Douglas and Gillies (1), a simple field test was given for gold. Later work by the present writers, and by others who have kindly written to us, shows that the test is not as satisfactory as it was hoped. In many cases, the gold mirror is completely obscured by a dense precipitate which, up to the present, it has been found impossible to remove. After many attempts, we have temporarily given up the iodine test and have been working on a simple pyridine reaction based on the work of Putnam, Roberts, and Selchow (2): The ore to be tested is ground to a fine flour. Place half a gram of this powdered ore (an amount that will cover a Canadian ten-cent piece, not heaped) in a six-inch test-tube and add 5 c.c. of aqua regia. The aqua regia. should be made up on each occasion, using four parts of hydrochloric acid and one part of nitric acid, both concentrated. Shake the solution in the test-tube for about one minute and allow to settle until dear. The rime to settle may be 30 to 60 minutes. When dear, a drop of the solution is with-drawn with a fine, dean eye-dropper or capillary tube and placed on à small glass plate. A slide such as is used for mounting rock sections is suitable. Now place an equal sized drop of pyridine solution on the plate beside that of the aqua regia solution to be tested. The pyridine solution, containing nine volumes of hydrogen bromide to one volume of pyridine, can be made up in advance and carried in a glass-stoppered bottle. Join the two drops with a glass thread or fine, dean stick, and allow the merged drops to stand undisturbed. I t is well to place the slide on a piece of white paper so that the presence of the crystals which may form can be easily seen. The time for their formation will vary with the amount of gold present, but the slide should be allowed to stand for at least 30 minutes before negative results are reported. A hand lens of at !east ten magnifications is essential. If gold is present, minute red crystals will form around the margin of the drops as these drops slowly evaporate.

Jan 1, 1938

Resistance spot welding is the most common type of welding in the automotive industry. In RSW the size and shape of welding nugget is one of the most effective factors on mechanical properties, such as tensile shear strength and fatigue strength. so properly adjusting the variables of the welding is necessary .in this study the effect of different parameters of RSW including time, current, electrode force, geometry of electrode so diameter and angle of electrode tip in the shape and size of welding nugget evaluated. for experimental procedure, low carbon steel sheet st12 is used. the process is simulated with finite element method by using ANSYS software. for the formation of welding nugget a 2 dimensional symmetrical model electrical-thermalmechanical is used and for elevate the accuracy ,we determined the properties of material related to temperature. The results show that increasing the time and current of welding, the diameter of spot weld also increased and the role of current is more impressive. and also increasing the electrode force decrease the diameter of the nugget due to increasing the contact area and decreasing the resistance .increasing the diameter of electrode tip cause increasing contact area and decreasing the resistance and decreasing the diameter of the nugget. furthermore, changing tip angle and electrode diameter don&apos;t show sensible change in the geometry of the welding nugget. comparison between simulation and experimental result show a good adaption.

Oct 1, 2011

By Karen I. McMaster

"Abstract - The mining industry has endorsed the concept of sustainable development in principle. We now need to ensure that it is "lived" throughout the workplace. Frequently, sustainable development is viewed as just a policy and, more often than not, it is regarded as something that is applicable only to the areas of health and safety, environment, or community philanthropy. However, sustainability requires the collective action of an entire organization on a regular basis, a corporate culture where values are transformed into action.This paper reviews two of the many functional areas through which sustainable development can be pursued. Law and internal auditing are powerful means of instilling values, driving behavioral change, and improving performance. The development and role of each tool vis-a-vis sustainability is reviewed. Suggestions are offered regarding option and joint venture agreements, contract management programs, and various auditing programs based upon international standards and processes, market indices, and codes of conduct.The goal of this paper is to provide a general overview of these functional areas and to encourage further dialogue between employees and management in the workplace. It is hoped that others in the industry will examine the values of their companies, and review the ways in which individuals in all functional areas work, or want to work, on a daily basis. If we can harness collective commitment, creative thinking, and action in sustainable development, then the desired acceptance by stakeholders and improved financial performance will follow."

Jan 1, 2003

By John Emery, George Wang

Research and applied utilization activities for the increased use of ferrous and nonferrous slags in construction are presented. The overall use of blast furnace slag is relatively well known for a range of construction applications from aggregates to slag cements. In contrast to blast furnace slag, which is volumetrically stable and straightforward in its construction uses, steel slag contains hydratable oxides that can result in volumetric instability that must be dealt with through appropriate steel slag aging, testing and quality control to ensure its appropriate use. Particular care must be taken to prevent potential steel slag expansive behaviour in confined applications. Quality requirements and guidelines on steel slag expansivity to further the use of steel slags, with demonstrated acceptable performance, are outlined. There is a full range of proven construction uses - from aggregate to cementitious materials - for copper, nickel and phosphorus nonferrous slag. The use of air-cooled nickel slag is presented, based mainly on practical highway construction experience. It has been shown that air-cooled, crushed nickel slag can be an excellent aggregate in granular base, engineered fill and hot-mix asphalt. There is a good potential for increased ground, granulated copper and nickel slags use as supplementary cementitious materials that is being developed, which takes advantage of the &apos;latent energy&apos; content. The scope of a new technical text in preparation on the technology of slag utilization is reflected throughout to provide a practical context for the engineer.

Jan 1, 2004

By J. Schmidt

Cold drawing of copper wire rod is usually combined with an in-line annealing process to adjust the ductile microstructure of the wire again. One important key factor for successful annealing is the quality of the copper itself. Rod producers can check the recrystallization behaviour of the rod by different methods: chemical analysis, Spiral Elongation Test (SEN) as well as the Rapid Elongation Test (AR) are some examples of common testing methods. The comparison of the results of these methods does not always show sufficient correlations. The paper introduces firstly the SEN and AR-Tests and their different approaches to the mentioned task. The second step is to compare some results of the SEN-Test with the results of the AR-Test and identify causes of deviations. Thirdly, the effect of pre-annealing is discussed, which is especially common for wire rod with diameters of more than 8 mm.

Jan 1, 2007

By J. P. Messervey

As a result of my field examinations in this Province, I have been struck by the evidence of widespread mineralization in rocks, particularly the limestones of Carboniferous age. Six prospects of lead and zinc or lead alone scattered through the eastern part of the mainland, one copper prospect and three veins of siderite, all point to a period of mineralization subsequent to the forming of the Carboniferous rocks in which they occur. While none of the present prospects are of proved economic importance, still it is possible, and indeed probable, that further prospecting will find concentrations sufficiently large to make mines. It may possibly aid the prospecting for these base metals if the present scraps of information are assembled from various sources, and I will further briefly recount the information as a result of my observations. Gay?s River At Gay&apos;s river, midway between Halifax and Truro, and four miles east of the railway, numerous pits and natural exposures show galena and sphalerite in limestone of Carboniferous age, near where it lies unconformably upon slate and quartzite of the gold series. These exposures extend for a length of over one thousand feet along a curving contact. The pits show that on the contact there is a fossiliferous and somewhat porous layer of limestone, which is so impregnated with galena and small amounts of sphalerite as to be of ore grade. Wherever observed, the thickness of this layer is less than two feet.

Jan 1, 1929

By G. Vibert Douglas

NICKEL minerals are known in New Brunswick but have never been reported from Nova Scotia. The attention of the writers was drawn to an occurrence of pyrrhotite, reported to carry nickel, at the Second Gold brook, Middle river, Cape Breton. The purpose of this paper is to record the occurrence and give an account of the general geological association. In a later paper it may be possible to give greater details? than are available at present. GEOLOGY The area lies at the edge of a plateau of Precambrian rocks which forms the panhandle of Cape Breton island. This plateau has a general elevation of 1,200 feet. Middle river, with its tributaries, the First, Second, and Third Gold brooks drains the area. The lower country to east and southeast of the plateau is underlain by lower Carboniferous sediments. The rocks of the plateau are presumably of Precambrian age but have never been definitely correlated with the Gold-Bearing Series of the mainland. ?There i:s; however, some resemblance, although they have apparently been more intensely mountain-built. They are essentially fine grained, sheared quartzites and slates . The general strike is east and west, with a north dip of 45° to 55°. There are smalllocal drag-folds in the area. The only igneous rock in the immediate vicinity is an intrusive pink porphyry. It has small phenocrysts of quartz and feldspar. It has intruded the sediments generally along the structural planes, but in places crosses the structure . Its intrusive character is further proved by the fact that it contains xenoliths of the quartzite.

Jan 1, 1937

By W. L. Stuewe

For the purpose of this paper I shall, in order to limit myself, define the words &apos;Maintenance&apos; and &apos;Equipment&apos; as follows: Maintenance shall mean the &apos;care of or &apos;the sustaining of equipment in as nearly perfect condition as possible. Equipment shall mean any item of a mechanical nature entering into the production of coal; it will be seen that unless one limits the use of this word it could take in administration as well as operative equipment, and include metal mines, mills and smelters, and manufacturing plants. In any industry the first consideration is the proper operation of all units entering into the production of the article manufactured or produced. I wish to quote here what a man, well known internationally in financial circles, told his operators at the time a large expansion programme was under consideration. His exact words were: "I do not care how much it is going to cost. What I want to know is how much it is going to cost to operate and maintain. It is the continuous drain for repairs that costs us the most money." The truth of this statement has been proved time and again, and many companies have found the cost of maintenance to be the balance between profit and loss-so much so that, in two instances with which the writer is familiar, the mechanical equipment was practically replaced throughout. I bring this point out here to emphasize the value and necessity of keeping abreast of the times, and obtaining maximum efficiency with the minimum outlay. Time is indeed money where delays occur due to defective or poorly kept equipment, and it is absolutely necessary to prevent machinery from becoming defective or inefficient.

Jan 1, 1930

By P. R. Stephenson

Mining projects depend on the amount and quality of the mineral reserves, which in turn depend on the amount and quality of the mineral resources. Only Measured and Indicated Resources may be converted to mineral reserves and Inferred Resources may not, with certain exceptions, be used in economic studies. Responsibility for the estimation of mineral resources rests with the Qualified Person (QP) and there is a wealth of literature, text books and case studies to guide the QP. Responsibility for the classification of the mineral resources also rests with the QP. While there is some industry guidance and common practice on approaches to resource classification on which the QP can draw, the process is (or should be) heavily dependent on the exercise of judgement by the QP. However, this inevitably leads to situations where, for example, one QP?s Inferred Resource is another QP?s Indicated Resource. If the QP?s judgement is poorly reasoned or illogical (as is sometimes the case), it can have a major impact on the project, often with substantial cost or value implications. Project managers and company executives should not unquestioningly accept QP?s classification decisions and should apply the same intensity of due diligence that they apply to other critical elements of the project.

May 1, 2011

By J. A. Haskin

The Engineering Department at Flin Flon has the following responsibilities: 1. Underground Surveying. 2. Open-Pit Surveying and Supervision of Blasting. 3. Mine Geology and Examination of Prospects. 4. Design of Plant Additions and Improvements. 5. Miscellaneous Field W ork, Reports, etc. The entire surface plant, as well as the underground workings, are located by co-ordinates based on a triangulation system covering an area approximately one mile long by one-half mile wide. The origin of this system and one end of the base-line is the southwest corner of Township 67, Range 29, west of the Principal Meridian. The bearing of the base-line was determined from the township boundary, which runs true north, so that all other bearings are almost astronomical. This is a great convenience when our surveys must be tied to mineral claims, rights-of-way, and land subdivisions. As the base-line extends across Flin Flon lake, its measurement across smooth ice was simple and accurate. The length, slightly over 1,600 feet, has been adjusted for the temperature and tension of the standard tapes used and checked sufficiently to ensure a maximum error of 1 : 15,000. Each angle was repeated ten times, but as no special refinements were used, errors of as much as four or five seconds are possible. The elevation of the origin of the triangulation system was approximately 1,050 feet above sea level. The use of this true elevation in our surveys would have resulted in negative elevations underground as soon as the mine reached a depth greater than 1,050 feet. To avoid this complication we therefore added 4,000 feet to this elevation. The collar of the Main shaft, for example, which is actually 1,072 feet above sea level, appears in our records as at elevation 5,072. Underground surveying, which follows standard practice, is done by two mine surveyors who share three helpers. The meridian is taken underground from two wires hung in either of the two vertical shafts.

Jan 1, 1935

By W. P. Corking

"The purpose of this paper is to describe the relationship of the goldbearing ore to structure at the Pickle Crow mfoe. Information beyond this scope may be found in the reports and papers of Hurst( l), Bothwell(2), Thomson(3) , and Monette( 4).The property lies on Crow river, in Patricia district, 80 miles northeast of Allanwater, and about 125 miles northeast of Sioux Lookout on the Canadian National railway. From April of 1935, when the mill began operation, to the end of 1944, a total of 564,890 oz. gold and 49,275 oz. silver were recovered from 958,416 tons of ore.Mining on the property is at present carried on in two separate orebodies, the Howell and the No. 2 vein. Stoping has been carried on from every level on the Howell vein to a depth ot 2,450 feet below the surface and from several levels on the No. 2 vein through a mile long cross-cut on the 750-foot level to the Howell vein workings. A steadily increasing volume of ore is being obtained from the No. 2 vein.Each of the two orebodies consists of vein quartz with small amounts of other gangue minerals either in a single vein or a stockwork of veins. Both lie within sheared walls and carry gold in the free state. Fig. 1 shows the position of the veins with respect to the surrounding rocks. It will be noted that the delineation of the beds of iron formation shows that the lava flows and minor, interbedded sediments that make up most of the country rocks are areally folded and contorted.STRUCTURENearly all gold found to date in sufficient quantity and concentration to make ore in the Pickle Crow area is confined to these major quartz veins . Both strike a little north of east and dip north, and in both cases the attitude of the enclosing rocks is somewhat more north of east in strike and more steeply north in dip than that of the veins. As a result of this disposition both veins migrate across their enclosing rocks at a moderate angle in both dip and strike. (In this connection it should be noted that No. 2 vein dips at a considerably flatter angle than its host rock, but has a very pronounced rake to the northeast, effecting the same result as in the Howell vein.)"

Jan 1, 1954

By R. Lepsoe

THE basic products of the Company are lead and zinc. Around 950 tons of these metals are produced each day. In the last decade, the production of by-products has increased to such an extent that they are now nearly as large an operation as that of the base-metals. Of the many by-products, the most objectionable, and up to a few years ago the most useless, was the sulphur. The sulphur comes in the ore from the Sullivan mine. It is in the ore chiefly as lead, zinc, and iron sulphide. By selective flotation, these three sulphides are separated into the lead concentrates, the zinc concentrates, and the mill tailings. These mill tailings contain the bulk of the iron and the sulphur. Of the 6,5CO tons of ore treated per day, about 5,000 tons are wasted to the mill tailings dump, and, while now valueless, will in future years undoubtedly be used as a source of iron and sulphur. There are about 1,500 tons of sulphur and 2,200 tons of iron per day in the tailings, and about 400 tons of sulphur left in the total concentrates. In the recovery of lead and zinc in the pure form, the first step is the roasting operation. Here, most of the sulphur is driven off as sulphur dioxide in the gases. It has always been apparent that this sulphur should be. recovered and utilized if possible. At the same time, this would cure the smoke nuisance. Because, in spite of the low concentration of sulphur dioxide and the fact that it was discharged from stacks at an elevation of 400 feet above the plant, some damage to vegetation close to the plant had been experienced.

Jan 1, 1937

The primary arsenic minerals in the uranium ore processed at the McClean Lake Operation are rammelsbergite, niccolite and gersdorffite. During processing, a large fraction (80 - 95%) of these reduced minerals is oxidized and dissolves primarily as As5+ in the leachate solution. In the tailings preparation circuit the dissolved As5+ is precipitated as a poorly crystalline form of the mineral scorodite. Following subaqueous deposition in the tailings management facility, a temporal rise and fall in arsenic pore water concentrations has been observed. This is due to the oxidation of the residual quantities of reduced arsenic minerals initially present in the tailings sediment. The XANES (x-ray absorption near edge spectrometry) technique has shown that the As1- is gradually oxidized to As3+ and then finally As5+ in the tailings sediment. This oxidation process results in a temporary accumulation of As3+ in solution and is the source of the rise and fall in arsenic concentration observed.

Aug 1, 2010

By G. C. Laurence

"This paper discusses the hazards and extensive precautions taken in Canadian uranium mines, concentrating plants and processing plants. It also outlines Canadian policy regarding the control of the sale and distribution of uranium and other nuclear materials.OVER THIRTY YEARS AGO, I spoke to The Canadian Institute of Mining and Metallurgy here in Montreal about radioactivity and its dangers. I must have made quite an impression thirty odd years ago, because now you have asked me to do it again. Of course, the picture has changed. Then they were mining uranium ore, recovering the radium from it and throwing away the uranium. Now they are still mining uranium ore, but are throwing the radium out on the tailings dumps. Thirty years ago, most people did not know what ""radioactivity"" meant. Nowadays, they have beard that it is dangerous, and some of them, recently, be-came worried about the radium in the tailings dumps and what becomes of it."

Jan 1, 1969