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By D. W. I. Griffiths, J. C. Bélanger

"La Division Matagami de Minéraux Noranda inc. a profité de la construction de sa nouvelle mine (Isle-Dieu) pour continuer sa modernisation.L'utilisation d'automates programmables (PLC) s'est intensifiée pour contrôler et automatiser de plus en plus d'équipement dans ses minessouterraines, au concentrateur, dans les atelierset bureaux.Tous les PLC comrnuniquent entre eux et les IBM PC sont utilisespour exterioriser l'information et faire Ie lien entre Ie personnel et les automates. Le système Central IBM 36 emmagasine les donnees traitees par lesPLC (a travers les PC). Ces donnees sont transmisesau programme d'entretien de chaque equipement et compile les heures, cycles, tonnes, etc., fait imprimer automatiquement les feuilles d'entretien préventif ', etc.Les principales realisations adate et en progrès pour la mine Isle-Dieu sont:• automation complète du système de remblayage du concentrateur ala mine Isle-Dieu situee a2 km de la mine principale;• automation du fonctionnnement des ventilateurs qui comprendra la position des portes de ventilation, Ie chauffage, Ie débit, etc.;• automation des pompes, surveillance des sous stat ions électriques, concentration des gas (CO, SO2) à chaque niveau en tout temps et du propane à l'entree d'air frais;• tonnage et cycles par Ie treuil; et• contrôle d'autres équipernents à differénts niveaux. D'autres travaux furent egalement effectues par les employes, tels que:• la conversion d'un Scooptram ST5A de diesel à électrique;• I'installation complete de systèmes de depoussierage a I'eau (scrubber) pour le concassage secondaire;• I'installation d'un marteau hydraulique avant les concasseurs coniques;• la rénovation des cellules de flottation ; et• l'installation d'un système de gardiennage par caméra. D'autres projets seront effectués ou étudiés:• automation d'un Scooptram"";• automation d'un marteau hydraulique;• récupération de Scooptrarn; téléguidé:• gestion de l'énergie, contrôle de la demande, surveillance et contrôle de l'équipernent de machines fixes(compresseurs, boulloires, pompes à vide, génératrices, débits et pression d'air, eau pour diagnostiquer les problémes, analyser les coûts;• concasseur portatif pour fabriquer de la pierre concassée pour utiliser dans les chemins sous-terre, et• utilisation de micro-ondes pour transmettre les images captées par camera."

Jan 1, 1990

By M. X. Yao, C. D. Opris, P. C. Patnaik, R. Liu, X. J. Wu

Two cobalt-based superalloys, Stellite 694 and Stellite 712, were functionally graded with reinforcement of titanium-carbide particle for high-temperature wear/corrosion applications. The designed composite specimens were fabricated using powder metallurgy (P/M) technique, combined with hot isostatic pressing (HIP). Calorimetric effects of the alloy powders were investigated using the differential scanning calorimetry (DSC) technique, which provided the basis of the sintering cycles designed. The phases present in the microstructures of the materials were analyzed using SEM and X-ray diffraction. The wear resistance of the materials was evaluated on a pin-on-disc tribometer. It was demonstrated that adding titanium-carbide particles to the alloys has increased significantly their wear resistance. It was also found that the HIP process had improved the density of the sintered specimens and thus enhanced their wear resistance.

Jan 1, 2004

By Miguel A. Cuba

Trends in the mean and/or variance are a longstanding challenge in mineral resource modeling. Geologic modeling and/or grade domaining are often employed to account for heterogeneities in mineral grades; however, this is only practical up to a certain point since the number of data available for reliable model construction can be severely reduced. In such cases, trends remain present in certain geologic/grade domains and directly impact the modeling methodology; the trend must either be handled explicitly or a suitable approach is adopted to implicitly account for it. This is highly dependent on understanding the source of the trend. We propose an approach that detects the source of non-stationarity, which is based on quantifying the impact of non-stationarity in the mean and the variance via the semivariogram. By expanding the methodof- moments approximation of the semivariogram, we decompose the experimental semivariogram is into three terms: 1) trend in mean component, 2) trend in variance component and 3) stationary component. We can then assess the source of trend by calculating the contribution of each component at every lag. Two cases are presented to illustrate this tool. Firstly, a synthetic reference model is simulated and different trend patterns are added; the influence of these patterns in the experimental semivariogram calculation are analyzed and discussed. Secondly, a real dataset is considered where the impact due to the presence of trends in the mean and variance are assessed. The results of this paper reveal the semivariogram to be a tremendously powerful tool in determining the source of the trend. This insight may be useful in the selection of a suitable modeling approach for resource estimation.

Oct 1, 2009

By J. M. D. Wilson, W. Petruk, C. Coté

"The behaviour of minerals in the Mount Wright spiral circuit was investigated to find methods of improving iron oxide mineral liberation and recovery. The feeds, concentrates and tailings from rougher, cleaner and recleaner spirals in one mill line were sampled before and after the sizing screen openings were reduced from 2 mm to 1.6 mm. Sized fractions of each sample were analyzed with the MP-SEM-IPS image analysis system at CANMET to determine mineral quantities and liberation characteristics of the iron oxide minerals. Mass balance techniques were used to calculate stream recoveries of iron, silica, total iron oxide minerals, hema¬tite, goethite, quartz, ferromagnesian silicates, and liberated and locked total iron oxide minerals for each sieve fraction.The reduction of the sizing screen openings increased the ap¬parent liberation of the total iron oxide minerals in the screen undersize from 89% to 94% and raised the over-all iron recovery from 84.4% to 85.3%. Apparent liberation of iron oxide minerals in the cleaner sand also increased from 70% to 85%, but the – 75 µm fraction re¬mained the only fraction containing an acceptable amount of liber¬ated iron oxide minerals in each case. Due to limitations of spiral and grinding efficiency it is recommended that the cleaner sand be screened at 300 m, the +300 m fraction be reground, and the – 300 p.m fraction be rerouted to the rougher spirals.The amount of fine liberated iron oxide minerals (– 106 m) lost in the tailings was 46 TPH in mill line 3. This value represents 41 wt % of the free fine iron oxide minerals, or 7 wt % of the total iron oxide minerals in the spiral feed. Further work is needed to investigate the possibility of recovering this material by other methods.Middling iron particles (010 50%) and presumably free gangue in the size range –300+ 75 m tend to be recovered by spirals by entrapment."

Jan 1, 1990

By Wei Wei

Mining induced ground movement and/or stress redistribution could cause ground instability issues. This is particularly true when the extraction of large stopes is done with one or two large production blasts. Often enough, it is the nearby mine development like haulage drifts and cross cuts that are influenced the most by production blasts. Proper and timely mitigation of ground control issues due to stress redistribution is required. This is usually done by drift rehabilitation involving the installation of secondary support system in the affected areas of the mine development which include; slashing, wire mesh, and in some cases the use of shotcrete liners. It is imperative that such rehabilitation be implemented to the mine infrastructure in a timely manner in order to avoid aggravated ground control problems and production delays. If the real time performance of the support system is captured, it would be possible to determine the timing for rehabilitation job. Birchtree Mine in Thompson, at the Vale Manitoba Operation, has begun mining the 84 Deep Orebody. One of the identified risks is the stability of the crusher room under mining induced stress redistribution. It is proposed to use the U-Cell technology to monitor the primary support system performance (rebar bolts and extension bolts) and monitor the real time performances of the bolt axial loads. The U-Cell technology is a 7-inch long, coupler load cell that is screwed onto the threaded portion of a rock bolt prior to installation. Rehabilitation in the vicinity of the crusher area where U-Cells are installed is recommended when the bolts have reached 70% of their yielding capacity. Catastrophic ground failure can be avoided by adding secondary support in a timely fashion. This paper presents a case study at Birchtree Mine in Thompson Manitoba, where the performance of primary ground support system is monitored and recorded during production.

Jun 1, 2012

By X. Z. Yuan

Contamination introduced by the impurities from the feed stream can impact the PEM fuel cell performance dramatically. The presence of these unwanted trace species such as CO, H2S, NH3, can adversely affect the fuel cell functioning. It has been reported that the major impact of CO and H2S contamination on the fuel cell performance is kinetic while the effect of NH3 contamination is speculated as membrane conductivity reduction only. In this paper, a model regarding the NH3 contamination is described and the mechanism of the NH3 contamination is illuminated by the model calculations.

Jan 1, 2005

By Louis R. Bernier

Most systematic studies carried out on passive treatment systems incorporating the use of limestone drains, under aerobic or anaerobic conditions, essentially deal with the treatment of effluents from mines in the USA. A limestone drain typically comprises a trench filled with crushed limestone rocks surrounded by impervious materials. In the case of anoxic drains, the trench is generally isolated under a geomembrane liner covered with soil. Contaminated mine effluents flow by gravity towards these limestone drains where the passive treatment consists in bringing the carbonates into solution, thus increasing the pH and alkalinity. Factors to be considered in the design are: chemistry of the contaminated mining effluent ([metals, [Al], [sulfates], dissolved oxygen, acidity, pH), desired residence time, nature of the rock, grain size, density, void ratio and mass of the limestone rock used, alkalinity, life span and hydraulic behaviour of the drain. Certain secondary effects (saturation by sulfates, co-precipitation, adsorption) may either be beneficial (lowering the sulphate and metal load) or harmful (armoring the limestone rock and clogging of the drain). This paper gives a brief status report on the available knowledge on the use of limestone drains for passive treatment of mining effluents heavily loaded with metals. Examples given include the old Lorraine mine (Ni-Cu), Témiscamingue, where limestone and dolomite rock drains were installed in 1998 when a cover with capillary barrier effects was placed over the tailings site.

Nov 1, 2002

By B. R. Rakishev

Balanced development of mining works at all the benches of a working zone by use of the excavator-automobile complex is achieved by transition to the technology of the bench excavating with cross panels by the two-sub-bench scheme with the changing levels of the working platforms (is patented in Kazakhstan). In deep quarries realization of this technology will allow to reduce the current volumes of the stripping ore excavation by 10?15 % and more, to increase the opened reserves of minerals by 20?50 % to decrease volume of mining-capital works for construction of stripping excavations by 2?4 times and to provide efficient use of powerful excavator-automobile complexes.

Aug 1, 2013

By Stephen Williams

This paper examines manning best practice in the Australian mining industry. In particular, the paper considers a range of mining operations and their manning levels as measured by operational benchmarking. The benchmarking results presented cover 15 open pit and 37 underground studies in Australia. The data was collected as part of AMC?s benchmarking and operational improvement studies conducted between 1999 and 2008. The results examine overall manning levels in mining, processing and administration functions. Manning levels for a range of mining methods, including open pit and underground methods, are segmented. Productivity measures such as ore tonnes per man day and metres developed per man day are presented and where direct relationships can be established, the relationships are described. Finally, the paper considers perspectives on best practice with regard to manning in the Australian mining industry and the limitations in application of this type of analysis in a global context.

May 1, 2009

By S. Afshar, E. Dajoux, C. Allaire

For various reasons, molten salts, mainly chlorides and fluorides, are used in the aluminum industry. In the holding and melting furnaces, these salts may have different roles such as protecting the metal from oxidation, reducing the metal content of the skim or removing inclusions or impurities from the metal bath. However, the use of these salts may also have some undesirable effects such as easy attack of the furnace lining refractory materials by molten aluminum. The aim of the present investigation was to clarify and to compare the effects of chloride versus fluoride salts, on the corrosion process of the aluminosilicate based refractory materials. A laboratory test and procedure, simulating the conditions at the metal line in the aluminum treatment furnaces, was used. Different aluminum alloys (A1-5wt.%Mg, A1-5.5wt.%Zn and 7075 alloy) and chloride or fluoride salts (MgC12, KC1, CaCl2, NaC1, MgF2, CaF2, NaF and cryolite) were used as well as several aluminosilicate materials. Thermogravimetric measurements were also carried out in order to analyze the effect of the salts on the oxidation of molten aluminum alloys. The experimental results showed that fluoride salts are more aggressive than chlorides against the tested refractory products. It is postulated that the fluorides prevent the formation of a protective oxide layer on the metal surface, favoring at the same time the corrosion of refractories. Moreover, it was found that the presence of Na in fluoride salts increases significantly the aggressiveness of the aluminum alloy towards the refractory samples.

Jan 1, 2004

By Ken Major, Anita Marks, Craig Sams

In 2007 Copper Mountain Mining determined that there were sufficient resources to consider reopening the Similco Mine near Princeton, BC. The mill facility that had been built by Newmont Mining in 1972 was closed in 1996 and all of the process equipment removed. The mill had been built on the west side of the Similkameen River to facilitate mining of the Ingerbelle Deposit. In 1980 construction was completed on a primary crusher and cable belt to deliver ore across the Similkameen River from the Copper Mountain deposit to the Ingerbelle mill. With the decision to restart mining of the Copper Mountain deposit, the decision was made to design and build a 35,000 tpd grinding and flotation mill near the mining operations. This paper discusses the application of historical operating data for the selection of the mills for the new grinding circuit and provides an overview of the grinding circuit design.

Jan 1, 2012

By W. G. Spencer, E. Sulis, P. M. Tiley

"Dome Mine's No.8 shaft is located about 1 km northeast of Dome's No.3 shaft and mill complex in South Porcupine, Ontario.No.8 shaft was brought into production in 1984 to hoist ore and waste for the complete mine as well as to service the mine from the 1600 level and below. Access above 1600 level is provided by No. 3 shaft.The rectangular shaft has six compartments consisting of two skips, a cage, counterweight, manway, and a service compartment. The over-all size of the shaft is 14 ft 7 in. by 20 ft by 7 in. (Fig. 1). A 7th compartment for shaft deepening is incorporated in the bottom 500 ft of shaft. The shaft is 5470 ft deep. The loading pocket is located at 5300 ft and the dump 61 ft below the collar.Surface facilities consist of a concrete headframe and a structural steel hoistroom which houses the cage and production hoists . The service hoist is a 12-ft diameter double drum, with one 1750 HP DC motor, and the production hoist is a 15-ft diameter double drum with twin 1750 HP DC motors.Both hoists have a single clutch and a single reduction gear train built by Orenstein & Koppel, and equipped with Canadian General Electric drives. The cage hoist is equipped with a disc pinion brake.The skips were originally aluminum 14-ton capacity, Rolla-chute design with steel liners on three sides and 4 in. of rubber on the back, to absorb the loading impact. The original guide rollers consisted of fixed 10 in. pneumatic tires. The face-to-face units were eventually replaced with larger airplane-type tires mounted on a spring loaded pivot arm."

Jan 1, 1993

By Peter J. Barnard

Mitochondria play a key role in the regulation of apoptosis (cell death) and in diseases characterised by abnormal apoptotic responses such as cancer. Mitochondrial membrane permeabilisation (MMP), regulated by the mitochondrial permeability transition pore complex, is widely accepted as being central to the process of cell death. As a result there has been considerable recent interest in targeting mitochondrial cell death pathways in the development of new chemotherapeutic agents.(1) There is potential to overcome the two overriding problems in cancer chemotherapy?the common occurrence of drug-resistant tumour cells and the lack of selectivity of cancer drugs in differentiating between tumour cells and normal tissues. Significantly, carcinoma cells have an elevated mitochondrial membrane potential relative to normal cells and lipophilic cations are concentrated within mitochondria in response to mitochondrial membrane potentials. There is potential for the selective targeting to tumour cells with compounds having optimal lipophilic-hydrophilic character. Research stemming from the early 1980?s points to two distinct classes of Au(I) phosphine antitumour agents where an antimitochondrial mode of action has been implicated: (i) neutral linear two-coordinate Au(I) complexes such as triethylphosphinegold(I) chloride and the tetraacetylthioglucose gold(I) phosphine complex, Auranofin; (ii) cationic tetrahedral bis-chelated Au(I) phosphine complexes related to [Au(dppe)2]+.(2) Recently it has been reported that Auranofin, at submicromolar concentrations, induces MMP observed as mitochondrial swelling and dissipation of membrane potential.(3, 4) Both events are completely inhibited by cyclosporin-A, the specific inhibitor of MMP. The permeability changes were shown to occur at concentrations associated with the selective inhibition of mitochondrial thioredoxin reductase.(3) Auranofin is a potent and specific inhibitor of this enzyme due to Au(I) binding to the active-site selenol group.(5) The redox state of mitochondrial thiols may be critical in the control of MMP.(3) In general, swelling is stimulated by thiol blocking or oxidising agents and is prevented by thiol reducing agents.(1) Mitochondrial thioredoxin reductase may play an import role in the redox control of the permeability of mitochondrial membranes.(3) Our interest is in investigating the antitumour potential of Au(I) phosphine compounds using a number of different approaches. In recent work we have evaluated a series of hydrophilic analogs of [Au(dppe)2]+ containing pyridylphosphine ligands which have demonstrated greater tumour selectivity than the parent compound. To investigate the possible antimitochondrial mode of action we are studying the effect of [Au(dppe)2]+ and related compounds on isolated rat liver mitochondria. To assess whether the lipophiliccationic nature of the compounds determines the antitumour activity, we have synthesized a series of novel Au(I) complexes based on heterocyclic carbene rather than phosphine ligands. The similar chemistry and structural features of the two classes of complexes allow us to assess whether the phosphine ligands are essential for the antitumour properties.

Oct 1, 2003

By M. Honarmand, Z. Moezifar, H. Ranjbar

Abstract - The Sar Cheshmeh area covers an area of 640 km2, and is located in the southern part of the Iranian Volcanic-Sedimentary Belt. ETM+ images have been used for alteration mapping. The Crosta method was found useful for enhancing exposed areas containing hydroxyl and iron oxide minerals. However, field checking has shown that this method is not able to identify all the known areas of hydrothermal alteration. Many of these altered areas are also not clearly resolved in the geophysical data. In order to improve resolution of such areas, integration of remote sensing and geophysical data may be helpful. The Darrehzar Cu deposit was chosen as a control area. The data have been divided into two sets: explanatory and target variables. The explanatory data are Landsat hydroxyl and iron oxide images and airborne geophysical data (K, U, and Th total counts, and total magnetics). The target variables are rock geochemistry and ground geophysics. Data analysis and integration of geophysical and remote sensing data were performed using directed principal components. This technique is found to be useful for the delineation of hydrothermally altered areas with more confidence.

Jan 1, 2002

By Charle Lawrence, Murray E. Blanchard

"A significant addition to Canada's commodity export transportation capabilities is being built by Ridley Terminals Inc. on Ridley Island in the Port of Prince Rupert on British Columbia's north coast.Site preparation began in early 1982. By the end of 1983 the terminal will be receiving coal from two major new mines being developed in B. C.'s massive $2.5 billion northeast coal development.The RTI terminal will have initial capacity to transfer 12 million tonnes of coal a year from railcars to storage and to ships. Capacity will be doubled to 24 million tonnes as market opportunities are developed.The challenge of building this $220-million facility in less than 24 months, the benefits Canada has received from the work the project is generating, and the long-term faith in Canada that this project represents, are all part of the excitement which surrounds the Ridley Terminal and northeast coal developments.RIDLEY TERMINALS INC. (RTI) is building a very significant addition to Canada's commodity export transportation capabilities. The facility, on Ridley Island at Prince Rupert, on the north coast of British Columbia, is a key link in British Columbia's northeast coal development which in itself is a massive undertaking involving investment of some $2.5 billion. The entire project is making a substantial contribution to Canada's economy at a time when such contributions are sorely needed.The development is creating employment, not only in British Columbia where its various parts are being created by mining companies, railways and others, but also across the country where suppliers are manufacturing a wide variety of good s and equipment for the development's participants.The RTI terminal is no exception. It is a critical cog in this mega project's large transportation system and its construction is contributing substantially to job creation and to other economic activity, in the Prince Rupert area and in many other parts of British Columbia and the rest of Canada."

Jan 1, 1983

By P. J. Urso

"This paper discusses the mining problems encountered at the Fording River coal mine to date, and how they have been solved. All of the production now comes from surface mining, but underground hydraulic mining is planned and briefly described. Other facets of the operation, including markets, equipment and personnel, are covered. IntroductionFording Coal Limited was formed in 1968 to mine and market metallurgical coal resources held by the company in the East Kootenay region of southeastern British Columbia. The company, at its Fording River operations, holds approximately 48,000 acres of coal lands, having an estimated 2.0 to 3.0 billion long tons of metallurgical coal in place. (Although not a point for further discuss ion in this paper, the company also holds approximately 1.0 million acres of mineral rights. These consist primarily of coal in Alberta, potash and coal in Saskatchewan, and minor industrial mineral holdings of limestone, salt and bentonite in the three western provinces.)Fording Coal is owned 60% by Canadian Pacific Investments Ltd. and 40% by Cominco Ltd. Inasmuch as Cominco itself is owned approximately 54% by CPI, it is seen that the effective CPI ownership of Fording is about 82%. The company, originally staffed and managed by Cominco, has been independent since January, 1978, with its own board of directors, management, staff and employees.The company's head office is in Calgary, Alberta. The Fording River operations are located approximately 45 miles north of the Crowsnest Pass, near the Alberta/British Columbia boundary, only 95 air miles and 200 road miles from Calgary.A contract was signed in 1969 with the Japanese steel mills to provide 45 million long tons of metallurgical coal over IS years, commencing in 1972 at an annual rate of 3 million long tons per year. Despite some start- up difficulties, the mine and plant facilities achieved their rated capacities in 1975, producing and shipping at the 3-million-Iong-ton level. The coal specifications are shown in Table I."

Jan 1, 1980

By W. G. Davenport

Methods of extracting copper are evaluated in terms of innovations during the 1970's, and predictions to the end of this century are made. It is concluded that between one and two new smelters and refineries will be needed per year until the turn of the century, and that most of these smelters will be of the oxygen or oxygen-enriched flash furnace type. For converting, the Peirce-Smith converter will still predominate, but the Hoboken converter will play an increasingly important role. Five Japanese pollution control systems are described and it is suggested that much of this technology will be included in future smelting installations. Further growth of hydrometallurgy is predicted, especially for oxide ores, based on improved product metal quality and low plant cost. A n increased level of scrap resmelting is also expected.

Jan 1, 1980

By H. E. (Buzz) Neal

"Abstract - The Labrador Trough contains world-class iron deposits which have been mined since 1954. The direct shipping of Knob Lake ores were mined at Schefferville from 1954 to 1982. Concentrate production began in 1961 in the southwest end of the Trough, with three mines currently producing concentrate and pellets at a rate of 35 Mt per year. West and north of Schefferville, several billion tonnes of taconite have been outlined in fine-grained, cherty magnetite iron formation. Several deposits of highly metamorphosed magnetite-specularite iron formation are located west of Ungava Bay. Numerous studies have shown that this medium- to fine-grained iron formation can be beneficated to 66% to 68% iron. In the area from Wabush Lake to Mont-Wright, a medium- to coarse-grained friable specularite-quartz iron formation is repeated by folding to form several large deposits. In this area, three mining operations are located with reserves and resources in the order of 5 billion tonnes.The iron deposits occur within iron formation in sediments in the extensive Proterozoic geosyncline called the Labrador Trough. Several facies of iron formation within the Sokoman Formation reflect variations in chemical composition and depositional conditions. The correlation between the mineralogy and textures is discussed to illustrate the development of different types of iron ores. This band extends for about 1100 km southeast of Ungava Bay through both Quebec and Labrador. Further south, it turns southwest past the Wabush and Mont-Wright areas to within 300 km of the St. Lawrence River. The iron formation is essentially folded and faulted along most of its length. The degree of metamorphism is variable, ranging from intense in the northern and southern portions to greenschist facies in the central portion.The stratigraphy, structure and mineralogy of the producing mines are described along with the history of discoveries. Geological input is required to achieve the strict specifications of the international iron ore market."

Jan 1, 2000

By John Lamb

"The French Mine (formerly the Oregon) is 4 miles by road south of the Nickel Plate Mine. It lies on the steep eastern slope of the Similkameen River valley at elevation 4,000 feet, between Cahill and Winters Creeks.The property was discovered in .1901 and bought 4 years later by Messrs. French and Deardorf. It was developed in a modest way by the owners and by several companies until 1947, without success. The spectacular showings of bornite and chalcopyrite in the outcrop drew attention to its possibilities for copper rather than gold. Diamond drilling by the owners in 1947 yielded several high-grade gold intersections and created new interest. In 1949 the property was purchased by Kelowna Mines Hedley Limited. Exploration drilling and geological mapping outlined sufficient ore to commence production in 1950. Except for a few months each winter the operation has been continuous, and to the end of 1954 had produced almost 30,000 tons of high grade ore. The ore is crushed at the mine and hauled 8 miles by truck to the Company mill at Hedley, where it is treated together with the ore from Nickel Plate.Regional GeologyThe country rock consists of brown tuff, flows, limestone, and cherty formations belonging to the Nicola group (Rice 1947) of Triassic age. West of and just below the mine is a large mass of granodiorite which is part of the same body that underlies Nickel Plate Mountain. Bedding attitudes in the mine area are locally complicated, but dips are generally less than 45 degrees. To the south and below the mine the beds stand almost vertical, continuing downward with this attitude for 2,000 feet to Winters Creek. The main granodiorite contact is also steep, conforming to the sedimentary formations, whereas northward towards Nickel Plate it dips gently to the northwest, slightly flattter than the thick westerly dipping pile of sediments above it. The interpretation of this structure by Billingsley (1936) is that the French mine lies near the crest of the large northeasterly trending asymmetrical anticline which contains in its gently dipping western limb the Nickel Plate orebodies. The granodiorite body conforming roughly to this shape seems to occupy the core of the anticline. Sill-like prongs of granodiorite extend upward to the east from the main mass, outcropping over wide areas at the head of Winters Creek (Figure 1). There is a possibility that overthrusting from the west, similar to that on Nickel Plate Mountain, occurs not far below the French mine.An interesting feature of the granodiorite-sediment contact is that where it dips gently westward no alteration exists in the sediments, but where it has a steep front pronounced heat effects are indicated by the presence of a thousand-foot-wide zone of reddish garnet skarn."

Jan 1, 1949

By D. Bronkhorst, J. Rheault

"Backfill practices at the Williams mine have evolved significantly since underground mining began in 1986. The use of conveyors as a means of transporting fill material to stopes has been discontinued in favour of load-haul-dump equipment. The method of adding binder to the fill product has been refined along with the placement technique. Slurry preparation has been fully automated and flyash is now included as a binding agent. Surface preparation of the fill product has evolved substantially with the quarry operation coming into full operation and the construction of pennanent crushing, screening, and storage facilities. Company personnel have replaced all contracted labour involved in backfill operations. Some changes have been made to achieve a higher standard of quality control while others were implemented as a matter of cost reduction. BackgroundThe Williams mine is one of three mines operating at the Hernlo gold deposit, located 40 km east of Marathon, Ontario, along the north shore of Lake Superior. Daily production at the mine is 6000 Ud yielding an annual gold production of approximately 500 000 oz. The orebody extends from surface to a depth of 1300 m dipping north at 70 degrees. The average orebody width is 25 m, but varies from 45 m on the eastern boundary to about 10 m at the western probable limit and at depth. Proven and probable reserves currently stand at 32 million tonnes grading 6 g/t.The Williams orebody has been divided into four separate mining zones: the A-zone, the West-of-Dyke zone, the B-zone, and the C-zone (Fig 1). Ore production originally was from the A-zone open pit operation while the A-zone and B-zone underground workings were being developed. The mining method employed underground is blasthole open stoping with delayed rockfill. Mining block dimensions are nominally 20 m along strike by 25 m high. Stope extraction is sequenced to achieve a relatively short pillar life and 100010 ore recovery. Pillars are extracted as soon as the adjacent primary stopes are two cycles ahead. Primary stopes are filled with consolidated rock fill after mining. This allows pillars to be blasted right against the consolidated fill, but also requires that the fill be self supporting to a height of 30 m.The Williams mine places approximately 1.4 million tonnes of rockfill and 50 000 tonnes of binding agents each year, with about three quarters of the fill placed being consolidated. The consolidated fill placed at the Williams mine contains Portland cement and flyash as binding agents."

Jan 1, 1994