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By G. Scott Zimmer

Mine planning at Cassiar consists of an annual cycle of projection, control, evaluation and revision following completion of annual diamond drilling during the summer months . The inherent difficulty in evaluating fibre grade and distribution, combined with a high-wall phase or push-back mining system, requires continuous modification to designs and schedules based on a cumulative evaluation of equipment performance and prediction versus production. To expedite the planning sequence, a mini-computer system has been introduced which allows emphasis to be placed on optimizing designs, exempting personnel from manual calculations and tabulations.

Jan 1, 1978

By A. O. Sfriso

"Numerical modelling is becoming universal in rock engineering practice. Most applications focus on the prediction of failure loads of 2D problems, where the numerical models are useful extensions to analytical methods and experience-based design criteria. For 3D problems and problems where the assessment of serviceability indicators – displacements, ground-structure response, etc. – are of importance, the selection of the constitutive models themselves and the implications of the selection of material parameters may have a very heavy impact on the reliability of the model outcome and its predictive capability.This paper overviews basic common aspects of constitutive equations used in practical rock engineering and summarizes some challenges that are frequently observed when reviewing numerical models performed for routine problems in rock engineering. INTRODUCTIONNumerical methodsFrom a philosophical perspective models, either analytical or numerical, are idealizations of a perceived reality. For us engineers, models are just tools we use to guide our judgement and understanding of the problem in hand. When dealing with problems in rock engineering, we resort to a wide range of techniques:1. Closed form solutions like confinement-convergence methods for circular tunnels: these methods satisfy equilibrium and compatibility requirements at the cost of a crude simplification of the material behavior and geometry;2. Limit analysis methods, like bearing capacity formulas: lower bound methods satisfy equilibrium but sacrifice compatibility, and upper bound methods do the opposite. Material behavior must be simple, geometry admits limited freedom;3. Limit equilibrium methods, like method of slices for slope stability: they satisfy restricted forms of equilibrium, do not satisfy compatibility requirements, require simple material behavior but have a much greater flexibility on geometry;4. Numerical methods, where a mesh is employed to discretize the problem geometry: when properly formulated, these methods satisfy equilibrium and compatibility requirements and give reasonable approximations to the behavior of very complex geometries and construction sequences. Very little restrictions remain on geometry and material behavior, but the cost of calibrating the material parameters can be very high."

Jan 1, 2015

By S. N. Aliferova, E. I. Afonina, S. N. Titkov, A. Ju. Bondareva, N. N. Panteleeva

"Potash ore is mainly processed using the method of cationic flotation. Potash ore deposits of the CIS, namely: at Upper Kama river, Gremyachinsk (Russia), Starobin (Belarus), Tubegatan (Uzbekistan) are characterized by relatively low KCl impregnation (1.0 – 1.5 mm) and contain up to 10% of waterinsoluble impurities (WII). Water-insoluble impurities are presented by aluminosilicate, silicate, carbonate (calcite, dolomite) minerals and anhydrite. In the process of milling the ore to a flotation size there are released and dispersed the insolubles impurities actively sorbing the cationic collector, i.e. aliphatic amines C16 – C22. In this regard there is carried out a preliminary desliming of the ore.Currently grinding the ore to a flotation size (1.5 mm or less) is carried out in rod mills along with forming of a large number of fine-grained ore fractions having the size under 0.25 mm, which results in the increased KCl losses with halite slime waste and reduction in the quality of finished product. There has been developed the technique for processing of potash ores with a high content of water-insoluble impurities (10 – 12%) containing, in different ratios, silicates, carbonates and anhydrite. The technology involves the use of the ore dry grinding to the flotation size and subsequent reagent activation of the processes for sludge removal and sylvite flotation.INTRODUCTIONCurrently there are being developed the potash ore deposits in the CIS countries, namely: at Upper Kama river and Gremyachinsk deposits (Russian Federation), Starobin deposit (Republic of Belarus) and Tubegatan deposit (Uzbekistan). Potash ores are a mixture of sylvite and halite and contain water-insoluble impurities of silicates, carbonates and anhydrite. The content of water-insoluble impurities (WII) reaches up to 10%, disseminated (impregnated) sylvite does not exceed 1.5 mm and in connection with that the ore is crushed to a particle size under 1.5 mm. Ore grinding is performed by wet process in rod mills with producing a significant amount of fine-grained mineral fractions and sludge, which are actively sorbing a cationic collector, i. e. primary aliphatic amines C16 - C22. The ground ore is deslimed and the slime product is directed to a sludge depot (pits)."

Jan 1, 2016

By I. Vazaios, M. S. Diederichs, N. Vlachopoulos

"As rock engineering moves from continuum to more discontinuum approaches for modeling, the engineer must make decisions regarding the degree of complexity to simulate for a given application, balancing the level of structural detail within the rockmass model with computational cost and result accuracy. It is important to consider that model does not need to include all the existent fractures and that representative geometrical properties for a given rock mass volume can be defined including only major structural entities.Within this paper, the scale-dependency associated with the geometrical properties of fractured rock is investigated utilizing a Synthetic Rockmass (SRM) approach with a view to characterize such ground to aid in the design of geotechnical works. In terms of process, the concept of the Representative Elementary Volume (REV) is used to determine the equivalent structural properties of the rockmass in order to justify the applicability of far-field behaviour of such ground. A large size Discrete Fracture Network (DFN) measuring 60m x 60m x 60m has been generated using the structural data obtained from LiDAR scanning of the Brockville Tunnel, Ontario, Canada. A number of DFN samples of varying sizes are extracted from the master network, generated using MoFrac, in order to be used as a the basis of the structural analysis of the rockmass. Volumetric measurements for the density and the intensity of jointing are employed in order to approximate the geometrical REV for the networks.In this paper a complete methodology of how to generate a DFN from LiDAR data and its analysis in order to determine the size of a geometrical REV is demonstrated. For the specific rockmass found in the area of the Brockville Tunnel, a geometrical REV measuring 3.5m x 3.5m x 7m is established. The results are generally in good agreement with the in-situ observations."

Jan 1, 2015

By Jacek Paraszczak

Possibility to move human workers away from dangerous places ?enhanced safety and improved working environment; ? Increase of actual operational time: ? Less losses due to shift changes, regulatory breaks, blasting periods, ventilation after blasting, etc.; ? Possibility to work in extremely dangerous conditions where man-operated machine could not be used (for example: ST-14 loader in backfilling operations in the Kemimine, following roof collapse). Reduction of the production cost through: ? Lower maintenance cost (less damage due to operator?s mistakes and no machine abuse); ? Higher productivity and effectiveness of the equipment (less machines to meet production targets, less operators required, lesser maintenance cost...). ? Although personnel health and safety are key drivers behind autonomous operation of mobile equipment in U/G mines, with significant capital and operation costs one expects to achieve: ? Productivity higher, or at least equal to that offered by man-operated equipment and systems; ? Lower production cost. Therefore, high effectiveness of the autonomous equipment is crucial to succeed.

May 1, 2010

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened sorne time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too expensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By V Dolmage

Copper Mountain is the third largest copper mine in British Columbia, and is now producing close to 20 million pounds of copper per year, with which is recovered also 4,000 ounces of gold and. 13,800 ounces of silver. After a long and checkered career, during which the ownership and management changed several times, this deposit finally came into the possession of the Granby Consolidated Mining, Smelting and Power Company in 1923. It was not, however, until the end of 1925 that the mine, under the management of Charles Bocking and C. H. Smith, was successfully placed on a basis of profitable production. It is a low-grade deposit of the contact-metamorphic type, with refractory ores consisting of chalcopyrite and bornite in a gangue of altered andesitic and basaltic breccia. The ore is concentrated to a product carrying over 30 percent copper, which is smelted in Tacoma. The deposit is 12 miles south of the town of Princeton, which is on the Kettle Valley railway, 150 miles east of Vancouver and 40 miles north of the International Boundary line. Princeton is served also by a branch of the Great Northern railway, which leads clown the Similkameen, Okanagan, and Columbia valleys. Copper Mountain mine and camp are connected to Princeton by a good mo tor road extending up Wolf Creek valley, while the haulage level of the mine, which emerges on the steep side of the Similkameen valley 1,000 feet below the camp, is connected with Princeton by a spur of the Kettle Valley railway leading up the Similkameen canyon and passing en route through Allenby, where the concentrator is situated.

Jan 1, 1929

By D. A. Livingstone

Abstract Golden Manitou Mines, Limited, nine miles east of the town of Val d'Or in northwestern Quebec, are presently milling, at the rate of 1,000 tons daily, a relatively complex 3.11-phide ore and producing, in decreasing order of value, zinc, silver, gold, lead, and copper. The products are a zinc concentrate, a silver-lead-copper concentrate, and a silver-gold precipitate from cyanidation. Although several independent pre-production metallurgical investigations into the treatment of the ore were carried out, current practice is different from any of the recommended methods and, while still leaving room for improvement, is considerably more effective than earlier performance. Flow-sheet developments from the commencement of operations in 1942 are dealt with briefly, showing the reasons for making numerous changes, the shortcomings of the various schemes tried, and, finally, covering data pertinent to present-day practice. From the recovery standpoint, silver has presented the greatest difficulty. The writer's association with the Company coincided with the start of production. Characteristics of the Ore The predominant metallic minerals present in the ore, in decreasing order of their abundance, are: pyrite, sphalerite, galena and chalcopyrite, with lesser amounts of argentiferous tennantite-tetrahedrite, arsenopyrite, covellite, bornite, and chalcocite. The sphalerite is mostly light in colour, sometimes colourless, and practically free from combined iron. Some of the sphalerite is very closely associated with minor amounts of pyrite, chalcopyrite, and galena. Pyrie is abundantly disseminated as medium to fine grains; more rarely it is massive and contains occasional grains of sphalerite, galena, and chalcopyrite.

Jan 1, 1952

By E. L. Martheleur

The use of electricity in coal mines dates almost from the time when it was realized chat it could be used to produce mechanical power. The first motor put in service underground was installed to drive a small pump nearly 40 years ago, and since then the use of electricity in mines has reached an extent undreamed of at that time. We now find its universal adoption in all the mining countries of the world. Great progress has been made in the development of mining electrical apparatus in the last decade, and excellent and adequate material is now available for the use of electricity underground. Although mining accidents, due to the use of electricity, are not frequent, the miner is justified in demanding chat all electrical apparatus for installation below ground be constructed with a greater degree of safety than that used on the surface. That this view is shared by the authorities of the different mining countries is evidenced by governmental regulations relative to the use, erection, and maintenance of electrical apparatus below ground. Those with which we are specially concerned are the regulations for the installation and use of electricity in the coal mines of Nova Scotia. The potential dangers of electricity in coal mines are: Shock or burns by contact from live parts. Shock or burns by contact with parts which, although normally dead, have become accidentally alive. Fire. Explosion of gas or coal-dust Explosion of apparatus.

Jan 1, 1928

Of the twelve known ore zones on the Sunro property, acquired by Cowichan Copper Co., only the "B" and "C" orebodies of the "River Zone" had been explored sufficiently to indicate the grade and tonnage. The "B" zone was selected for initial production. The portion of this orebody above the main adit level was developed for horizontal-ring, longhole mining. Ore from the stope would be scraped directly to the coarse ore bin. The lack of a suitable mill site on surface, as well as the 8,000-ft. tramming distance, led naturally to the installation ground. I N November, 1960, a lease was obtained by Co-wichan Copper Co. Ltd. (N.P.L.) from Sunro Mines Ltd., covering the main ore (River) zone of the Sunro property. A total of twelve zones had been located on the property. Nine of these lay within the leased area. With the exception of the "B" and "C" orebodies of the River Zone, there had been insufficient exploration for tonnage and grade calculations. Exploration by previous companies had

Jan 1, 1965

By A. L. Valdivieso

"The correlation obtained by plotting pH of maximum adsorption of dextrin versus the isoelectric point of involved metal hydroxides can be used to predict the depressing effect of dextrin on flotation in ""pure"" sulfide mineral systems. Sulfides are strongly depressed by dextrin whenever their surfaces are coated by the corresponding metal hydroxide. The efficiency of dextrin as a depressant is affected by the adsorption of the sulfhydryl collector. Hydrolyzable cations modify this relationship in flotation of sulfide ores. This type of deviation of the real-life systems from the predictions based on the behavior of the pure systems shows the possible ways that could be followed to further improve the obtained correlations. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists ofCIM Sudbury, Ontario, Canada Edited by"

Jan 1, 2009

By G. C. Mackenzie

At the last Annual Meeting of the Institute, Dr. C. V. Corless sketched the potential mineral wealth of Canada so clearly, graphically and with-all so entertainingly that one's imagination was fired with the promise held out to future generations for the tremendous expansion of the mining industry in the Dominion. Posterity will undoubtedly witness the fruit of much of the geographical search and survey that is now carried on by our government mining departments. Year after year the work advances, slowly but surely, new areas are . explored, older areas are surveyed in detail, the information being compiled in maps and reports of incalculable value to the prospector, the engineer and the general public. The immensity of the task of exploring, geologically, the outlying portions of the country, with the ultimate view of making valuable mineral discoveries, may be visualized from a study of Dr. Corless' paper and the subsequent discussion which took place and one becomes impressed with the fact that three-quarters or more of the problem can be included under the word "transportation". For instance Dr. Corless said, "The few geological explorers who have penetrated to these remoter regions . . . . . . have as a rule been compelled to stick closely to canoe routes,"; Dr. Goodwin remarked, "This barren Laurentian granite, which is put down on the maps as covering the greater part of this area, is the best guess the geologist could make from travelling along watercourses Within the next few years . . . . . . the Timiskaming and Northern Ontario railway will undoubtedly be extended to James Bay . . . . . . In order that we may be prepared for the probable influx of prospectors when transportation facilities to tidewater are provided, I think all available information on this district should be gathered together in handy form." All three-Corless, Goodwin and Cole-emphasize the well-known fact that explorers, geologists and prospectors working in new country must stick to the watercourses and that transportation by rail, road or water has always been the all-important deciding factor in facilitating the exploration and development of remote districts. Dr. Corless did, however, suggest other means of transportation in stating, "The aeroplane will be of assistance in future study of some parts of these remote areas."

Jan 1, 1924

By D. Haraguchi, S. Izawa, C. Tokoro, S. Owada

"Arsenic is widely known as a toxic element for humans, animals and plants. Because of more stringent wastewater standards not only in Japan but also around the world, research for appropriate and efficient treatment method for arsenic is becoming increasingly important. Coprecipitation or adsorption process using ferrihydrite is widely implemented for dilute As(V) removal from wastewater. In this study, the sorption mechanism of dilute As(V) with ferrihydrite in coprecipitation or adsorption process was investigated. To accomplish this, we conducted batch experiments of coprecipitation or adsorption and compared these results for sorption isotherm and zeta potential. These experimental results showed that sorption mechanism in coprecipitation process depends on the initial As/Fe molar ratio; simple twodimensional adsorption onto the surface of ferrihydrite when the initial As/Fe molar ratio was < 0.4, and some three-dimensional uptake with ferrihydrite when it was = 0.4. We also evaluated the sorption mechanim by analysis of X-ray diffraction (XRD) and X-ray Absorption Fine Structure (XAFS). XRD or XAFS spectra showed that surface precipitation of amorphous ferric arsenate was formed when the initial as/Fe molar ratio was = 0.4, beyond the thermodynamic bulk precipitation range for ferric arsenate.INTRODUCTIONArsenic is toxic to animals, including humans, and long-term exposure to arsenic via drinkingwater causes cancer of the skin, lungs, urinary bladder, and kidneys, as well as other effects on the skin such as changes in pigmentation and thickening (Ghosha et al., 2008). Elevated levels of arsenic are often present in the environment as a result of the weathering and dissolution of minerals as well as in response to numerous anthropogenic sources including the discharge of mine wastes, coal fly ash and the use of pesticides that contain arsenic (Nriagu, 1994; Singh et al., 2007). Indeed, the potential for arsenic exposure affects many people, as evidenced by several million people in Bangladesh and India being at risk of exposure via drinking water obtained from contaminated groundwater sources (Ahmed, 2001).Acid mine drainage (AMD) containing arsenic is a global environmental problem (Dold, 2008; Liang and Thomson, 2008) that also affects Japan, which has many abandoned or closed mines that have been generating AMD for the last few decades (Masuda et al., 2008). Several such facilities in Japan produce AMD containing dilute concentrations of arsenic that exceed Japanese effluent standards (0.1 mg/dm3) (METI, 2006). For example, AMD from the abandoned Horobetsu sulfur mine, the largest AMD source in Japan, contains approximately 10 mg/dm3 arsenic."

Jan 1, 2012

By M. van de Vijfeijken

This paper will first give a short overview of the Copper Mountain project in British Columbia, which just has started commercial operation earlier this year. The grinding process with one 34&apos; x 20&apos; SAG mill and two 24&apos; x 39.5&apos; ball mills will be briefly discussed. All three mills are gear driven by a ring gear, dual pinion and two low speed synchronous motors. Copper Mountain has installed on all three mills, the new state-of-the art dual pinion mill drives. All the inherent operation and maintenance features of this drive technology will be discussed, as well as the advantage of having variable speed control also on the ball mills. The installation and commissioning of the mills and drives at Copper Mountain will be briefly reviewed. Finally the first field measurements on these low speed mill drives will be presented, with the main focus on the low mechanical stress impact of these mill drives on the pinion and ring gear, as well as the accuracy of the load sharing between the two motors.

Jan 1, 2012

By D. H. C. Wilton, W. A. Sears

"Abstract-The 682.8 ± 1.6 Ma Tickle Point Group consists mainly of rhyolite flows and tuffs with- in the Avalon Zone of the Appalachian Orogen in Newfoundland. Stratabound massive sulfide mineralization, consisting of pyrite, sphalerite, chalcopyrite and galena, occurs at the Winter Hill prospect, where a lower pyritic, Cu-rich zone and an upper Zn-Pb-rich zone are hosted by a carbonate-calc-silicate lens. At the Frenchman Head prospect, stringers of pyrite, minor sphalerite, chalcopyrite and rare galena are hosted by felsic volcanic rocks of the Tickle Point Group .Base metal ratios, metal zonations and the overall stratigraphic framework suggest that these sulfide occurrences represent volcanogenic massive to semi-massive sulfide mineralization (stringer type at Frenchman Head). As such these prospects represent the only known VMS occurrences within the Avalon Zone of Newfoundland. Pb isotope data indicate that galena from the Winter Hill prospect is less radiogenic and older than galena from Dunnage Zone occurrences, and suggest that the Winter Hill mineralization formed in an environment tectonically distinct (exotic) from the Dunnage Zone."

Jan 1, 1996

By Peter Hood

Data on world-wide geophysical activity in mining exploration programs are collected annually by the Society of Exploration Geophysicists' Geo-physical Activity Committee as part of a continuing service to the industry. The data are obtained by sending out questionnaires to all organizations which are known to be carrying out mining geophysical work; the organizations canvassed include mining companies, contractors, government departments and universities. The questionnaire is divided into three sections; namely, ground methods, airborne methods and research. The data compiled from the questionnaires show that world-wide utilization of mining geophysical methods reached a new high in 1967 with total expenditures of (U .S.) $32,323,240. This was divided as follows: ground methods, $18,106,785; airborne methods, $10,-123,405; and research, $4,093,050. For the ground methods, most money was spent on the induced polarization technique ($5,681,780); electromagne-tic methods were second in reported expenditures ($2,010,900). The total reported geophysical line mileage flown was 1,275,072 line miles, with aeromagnetic surveying being the most popular airborne method. The total amount spent on aeromagnetic surveys was $5,832,564 for 895,420 line miles. This gives an average cost of (U.S.)$6.50 per line mile.

Jan 1, 1968

By Richard J. Wardle, Ambrose F. Howse

The industrial minerals industry in Newfoundland and Labrador is a significant contributor to the provincial economy. The variety ofcommodities produced reflects the diverse geological environment from which they come. A highlight of the past decade has been the continuing development of dimension stone quarries, with producers now active in anorthosite, gabbro, granite and sandstone. Other dimension stone prospects have been identified and are in various stages of assessment and development. Western Newfoundland hosts a large resource of limestone, dolomite and marble. It provides raw material for industries that produce Portland cement, agricultural limestone and aggregate, as well as chemical-grade limestone and dolomite products. In western Labrador, dolomitic marble is quarried for use in the production of self-fluxing iron ore pellets. The recent opening of a new gypsum quarry at Fischells Brook signalled the beginning of a new era in the commercial production ofgypsum, a commodity which the province has produced since the 1950s. Hopefully it will emulate the nearby Flat Bay Quarry (now closed) which was a long-time exporter to markets along the U.S. eastern seaboard, in addition to supplying local demands. Oil production and continuing exploration in the Newfoundland offshore has renewed interest in local barite deposits for potential use in drilling fluids. Already there has been some production from the Collier Point deposit, and at Buchans, an existing plant is being refurbished to recover barite from a large tailings pond. Emerging new industries include the development of an antimony mine in central Newfoundland, the development of silica deposits near Labrador City for silicon metal production, and reactivation of the St. Lawrence fluorspar mine. The province has many deposits with development potential such as rare metals at Strange Lake, white marble at Roddickton and salt deposits near St. George's Bay region.

Jan 1, 2001

By M. Leroux, J. A. Finch

"Sizing below 38 µm (400 mesh) is an increasing requirement in mill testing laboratories. The Cyclosizer is gaining wide acceptance in this role. A recent alternative is to use electro-formed sieves (micro-sieves), which are available with openings down to 5 µm. The advantage of micro-sieving is a cut size which is independent of mineral density, easier retention of the fi nest fraction and reduced purchase cost. A simple method of microsieving using an ultrasonic bath, which performs readily to 10 µm, is described.A systematic study of Cyclosizing and micro-sieving is reported for three samples; silica, copper oxide and a lead concentrate. Micro-sieving gave comparable results. Comparison with a standard sizing method, the Sedigraph 5000D, revealed misplaced material in each fraction by both methods. The range for micro-sieving was from 20% to 60% depending on the sieve and material; for the Cyclosizer it was a consistent 40-50% for all cones and all materials. The Cyclosizer can be sensitive to feed mass and particle size for dense materials. It is recommended that for minerals of specific gravity greater than 5, no more than 35 g of -38 µm be used.The disadvantage of micro-sieving is that it requires continuous operator attention and sieving time depends on sample mass. To fractionate 35 g-as used on the Cyclosizer and considered at reasonable mass for mill testing purposes-through 25-, 15- and 10-µm sieves requires about 80 minutes.IntroductionParticle size has a pronounced influence on mineral separation processes. Consequently, the measurement of particle size plays an important part in mill testing. By far the most common method is by screening. This, however, is usually limited to 38 µm (400 mesh) or occasionally 25 µm (500 mesh). Increasingly, mineral products are becoming finer than this limit and consequently finer sizing methods are required."

Jan 1, 1982

By L. H. McKay

Tailing Dams Three types of dam have been structed to impound tailings from the Allenby mill: 1.- By classifier unit 2.- By earth dam 3.- By direct deposition of tailings The first type, which includes two dams, was built across a shallow valley which sloped down to Similkameen river, just below the mill site. Two earth embankments, one below the other, were built across the valley. Tailings were then piped to Akins classifiers mounted on wooden wheels. The classifiers were set up at one side of the valley and gradually moved ahead on the sand embankment created by the sand discharge from these classifiers, the slime overflow going to settli.ng ponds formed by the dams. Decanting wells were built in the settling ponds by placing four six-by-six timbers vertically in the ground, two feet apart, to which two-by-six tongue-and-groove boards were nailed. The elevations of the ponds were raised, as required, by nailing additional two-by-six boards on the well and bolting on more six-by-six timbers when required. The bottoms of the wells were attached to a covered launder made of three-inch lumber laid on a one per cent grade. This launder carried the overflow through the dam. The second type of dam was built across a long, narrow valley, known as Hitchen&apos;s Flat, the upper ~n d of which was about 2½ miles north of the mill. This valley, an ideal tailings site, was 4,000 feet long and from 600 to 800 feet wide. An earth embankment with a concrete spillway through the top was built approximately 28 feet high across the lower end of this valley. Tailings were then dumped into the upper end of valley, with no further expense until the basin was filled up to the level of the flume where this entered the valley. When the upper end of the valley was filled to this point there was still room for more tailings at the lower end. Therefore, a pump was installed to elevate the tailings to build a wall around the upper end of the valley by depositing sands from a launder built up on 20 foot supports and sloping both ways from the pumping station around the upper end of the basin.

Jan 1, 1950

By David Ulrich Furrer

Materials and manufacturing processing technologies have played an important role in the development and capabilities of nearly all manmade products. Market drivers for fuel efficient, low cost, environmentally friendly, more capable transportation has given rise to significant materials challenges and subsequent developments. The rate of improvement and implementation of new commercial products can be limited by the rate of new materials and process technology development and qualification. As many materials are being designed for unique requirements and even location-specific unique properties, the implementation of tools and methods to enable rapid characterization and validation of material definitions and design systems must also be accelerated. A review of new integrated material, manufacturing process and component designs, engineering processes and emerging tools and methods will be discussed. The linkage of computational materials science and engineering into component design will also be discussed along with the challenges and opportunities for further growth and application of integrated computational materials engineering (ICME).

Jan 1, 2015