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By A. M. Salomon de Friedberg

With respect to impurities, HBM&S' copper smelter, located in Flin Flon, Manitoba, is in an unusual position. In addition to the usual concerns, the fact that copper and zinc production at Flin Flon is closely integrated results in the unique situation where feed to the copper smelter typically contains 7% to 8% zinc. This paper discusses the ramifications to copper smelter operations resulting from the marriage of HBM&S' metallurgical plants. Distributions of impurities (specifically Zn, Pb, Ni, As, Bi, Sb, and Cd) are presented and operating practices designed to reduce the impact of impurities on anode copper quality are detailed.

Jun 1, 1993

By T. A. Lloyd

"This paper indicates the extent to which Canadian coal mine operators have taken advantage of developments in the science and technology of coal that would allow them to better satisfy changing market demands through improving the properties of their products. At some mines, no attempt is made to alter the coal from its as-mined condition, but at most mines grading into various size ranges and hand-cleaning of lump sizes is undertaken.Over-all, Canada Jags behind most of the other major world coal producers in the proportion of its coals being processed in wash plants. To some extent, this is due to the fact that a high proportion of the coal production satisfies market demands without such treatment. On the other hand, a few of the coal mines in Canada, which produce about 25 per cent of the nation's total coal output, have in operation some of the most modern coal beneficiating equipment available, including jigs, flotation cells, water cyclones, centrifuges, disc filters and thermal dryers."

Jan 1, 1968

By A. M. Salomon de Friedberg

"With respect to impurities, HBM&S' copper smelter, located in Flin Ron, Manitoba, is in an unusual position. In addition to the usual concerns, the fact that copper and zinc production at Flin Ron is closely integrated results in the unique situation where feed to the copper smelter typically contains 7% to 8% zinc. This paper discusses the ramifications to copper smelter operations resulting from the marriage of HBM&S' metallurgical plants. Distributions of impurities (specifically Zn, Pb, Ni, As, Bi, Sb, and Cd) are presented and operating practices designed to reduce the impact of impurities on anode copper quality are detailed.IntroductionHudson Bay Mining & Smelting Co. Ltd. (HBM&s), has been operating its metallurgical complex located in Flin Flon, Manitoba, since 1930. The smelter and zinc plant were originally separate entities with respect to production. The smelting operation consisted of traditional multiple-hearth roasters, a reverberatory furnace and Peirce-Smith converters. The zinc plant also utilized multiple hearth roasters and then followed with sulphuric acid leaching, purification and electrowinning. The zinc plant also recovered cadmium from a separate purification/electrowinning circuit.The two plants operated essentially independently of each other until rising zinc levels in the copper concentrate and large stockpiles of zinc-rich leach residues prompted the construction of the fuming plant in 1949. The smelter used pulverized coal to reduce zinc oxide present in the reverb slag and then captured the resulting zinc bearing fume in the fuming plant baghouse. The fume was sent to a separate ""oxide roaster"" in the zinc plant where it was first roasted to remove halogens and then leached to recover the contained zinc. This oxide fume became a major source of feed to the zinc plant accounting for roughly one quarter of the total zinc production. Furthermore, through the smelter's treatment of sulphide leach residue, both copper and zinc recoveries were improved for the over-all complex."

Jan 1, 1993

By E. C. Harder

BRITISH Guiana, Great Britain's only South American colony, may be reached by very comfortable steamers, both from North America and Europe. The trip from North American Atlantic ports requires about 12 to 14 days; that from Europe about 18 to 20 days. A number of steamship lines, including Canadian, American, and Dutch, have regular sailings between North America and British Guiana, with calls en route at various interesting ports in the West Indies and northern South America. Moreover, several lines, including British, German, and French, have steamships operating regularly between Europe and the West Indies. Indeed, so popular have the West Indian voyages become in recent years that, during the winter months, special cruises in considerable number are organized for many vessels that ply in the trans-Atlantic service in the summer. A trip to British Guiana, therefore, has become a delightful experience. After visits at the various attractive Leeward and Windward islands and Trinidad, the approach to the low, flat, British Guiana coast, with its muddy coastal waters extending for many miles offshore, is somewhat of a contrast. Arrival in Guiana waters is signalled by the appearance of the modern high-power Demerara Light, located "on a shoal about twelve miles from the mouth of Demerara river. From this point, if the tide is right, a pilot takes the steamer across the bar, eight to ten miles offshore, and into Georgetown harbour. At high tide, the water above the bar ranges from 15 to 18 feet in depth, depending on whether it is neap tide or spring tide; at low tide, the corresponding depths are 9 to 11 feet. As the bar is of soft mud, however, it is usually possible for vessels to pass over it with a draught of about two feet in excess of that indicated by the tide tables. Upon nearing the shore, one sees first the Georgetown wireless towers, then the light-house and the tall chimneys of sugar mills and of various factories in Georgetown, and finally the palms and other tropical trees and the houses of Georgetown itself along the sea shore and the east bank of Demerara river. Extensive wharves operated by various exporting and importing companies stretch along the river bank and activity prevails in Georgetown harbour. The principal exports are sugar, rice, gold, diamonds, bauxite, balata, lumber, fruit and other tropical products. The imports are food-stuffs, wearing apparel, and manufactured materials of many kinds.

Jan 1, 1936

By V. L. Eardley-Wilmot

Introduction We are all familiar with the bright and attractive colours of the roofs of our suburban houses and country cottages, but few of us fully appreciate the complex and highly technical nature of the business which produces these roofings. Roofing granules consist of small broken particles of certain types of rocks, burned clay products, or slag. They are used either in their natural state or artificially coloured and are affixed onto one surface of asphalt sheeting. Their main functions are to protect the roof against external fire hazard, prolong its life, and enable it to withstand extremes of weather over a period of years without deteriorating. Pleasing designs and colours are added attractions. The reverse, or inner side, of the sheeting is coated with a film of talc or fine mica to prevent it sticking when rolled up for convenience of handling for transport. The finished sheets or strips are cut into a variety of shapes for roofing shingles, or for sidings which resemble rows of bricks separated by mortar. In Canada, the consumption of roofing granules has increased fourfold in the past decade and indications are that the industry will continue to expand. At present, fourteen plants are engaged in manufacturing granule-coated roofings, but, apart from a relatively small output of natural granules by two producers in British Columbia, only one eastern producer makes both natural and coloured granules in Canada, and these only for its own use. The annual consumption is now over 77,000 tons of roofing granules valued at more than $1,600,000, but about 62 per cent of the tonnage is imported. It is thus apparent that the production of Canadian-made granules, both natural and coloured, could be considerably increased. This paper is presented in order to give an outline of the industry and at the same time to point out its difficulties and pitfalls.

Jan 1, 1946

By P. G. Thornhill

EARLY in 1951, Falconbridge undertook a research program aimed at the development of a sulphate roasting process for the recovery of the non-ferrous rnetals from the nickeliferous pyrrhotite fraction of Falconbridge ore, in order to reduce the tonnage of iron entering the srnelter. Such a method, it was hoped, would permit a high recovery of the nickel from pyrrhotite otherwise entering the smelter feed, thus not only raising the grade of the latter and reducing its iron content, but also providing an iron oxide residue useful as a source of by-product iron ore. At an early stage in the exploratory laboratory test work it was found that the degree to which the nickel could be solubilized by the sulphating roasting treatment was limited by particle size and the ex-tent to which the pyrrhotite concentrates were freed of the nickel occurring as physically separable pentlandite, a mineral relatively difficult to roast. ( 1) Thus the program

Jan 1, 1961

By J. E. Nesset

Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right 'strength' is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry may also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.

Jan 1, 2009

By T. N. MacAuley

"The Ingerbelle and Copper Mountain deposits are located near Princeton in southern British Columbia. They are owned by Newmont Mining Corporation's wholly owned subsidiary, Similkameen Mining Company Ltd. The property includes the Copper Mountain mine, a former producer. Ore reserves recoverable by open-pit mining are estimated to be 76 million tons containing 0.53% copper. Production commenced during 1972 at a rate in excess of designed capacity (15,000 tpd). All of the known major copper deposits in this area lie in a 14,000- by 3,500-foot belt of Triassic volcanics (Nicola Group) that is situated between a well-defined syenitemonzonite- diorite stock on the south and a variable intrusive complex on the north. The Nicola rocks consist of andesitic tuffs and agglomerates with lesser amounts of flows and some lensy siltstone layers. The orebodies are essentially disseminated sulphide deposits, although fracture-fillings are also important in many areas. Total sulphide content is usually less than 5%. At lngerbelle, and at Pit 2 and most of Pit 1 at Copper Mountain, the sulphides are chalcopyrite-pyrite. In part of Pit 1 and most of the former underground mine they are chalcopyrite-bornite. At lngerbelle the predominant alteration associated with mineralization is a pale greenish-gray bleaching of the dark andesitic rocks. This has been identified as albitization, with lesser amounts of epidote, chlorite, biotite, scapolite and calcite. This bleaching is plentiful at Pit 2, but K-feldspathization is also evident here. These orebodies can better be classified with pyrometasomatic deposits than with typical porphyry coppers. Their relationship to intrusives, the probably extensive metasomatic replacements, the evidence of pneumatolytic activity, the formation and redistribution of magnetite, and the irregular distribution of mineralization are all characteristic of this class. Deep-seated faults probably acted as channelways for mineralization; fracturing, faulting and rock contacts influenced ore localization in detail."

Jan 1, 1973

By H. W. Manley

SULPHUR, like the minerals of coal, iron and petroleum, is one of the essential materials in our modern expanding industrial civilization. Before discussing the salient features of the production of sulphur from the Canadian sour gas, it seems appropriate to outline the historical past and probable future utilization of sulphur. The ancient Greek writer Homer spoke of its "pest-averting sulphur" and the "divine purifying fumigation". Ancient alchemists found sulphur to be a fascinating and baffling material. The discovery of gun powder in the year of 1250, and its application to the art of war a, century later, made sulphur an important commodity in the progress of mankind. The initial manufacture of sulphuric acid in the year of 1736 by the Englishman Joshua Ward, established the basis of a chemical industry that today utilizes 80 per cent of the consumption of elemental sulphur. Commercial production of the chemical soda ash ( N a2C03) discovered in 1787 by the famous Leblanc Process, in-creased international demand for the element sulphur and marks the birthday of the Sicilian sulphur industry.

Jan 1, 1961

By D. Nower

"The supply of copper is expected to be at a large deficit in 2012. To recover from these deficits mining companies are required to maximize production and there is no better way to accomplish this than to optimize the use of their mobile mining equipment fleets. To optimize these fleets, each equipment type has to be monitored in its own unique way. Automation would not only improve production, but also minimize the safety risks and eliminate planning errors. The automated vibration monitoring of multiple systems on the shovel can determine the machine’s condition at all times. This reduces unplanned downtime and keeps critical shovels in production. This paper will discuss the details of how shovels can be successfully monitored, continuously. INTRODUCTIONP&H Mining, part of Joy Global, is the world’s largest manufacturer of above-ground mining equipment. Its electric rope shovels, such as Figure 1, with capacities up to 115 tons (104.3 metric tons), are used for high production loading in surface mines; its draglines, such as Figure 2, have bucket capacities to 160 cubic yards (122 cubic meters). P&H also produces blasthole drills, mobile mining crushers and other essential mining equipment. Headquartered in Milwaukee, WI, the company does business on every continent, except Antarctica. ECONOMIC FACTORSDue to the global demands for metals and power, mines are required to operate at full capacity. Mine operations cannot afford any critical assets to shutdown unexpectedly; depending on the ore type and quality, downtime for a single shovel can be as much as $300,000 per hour.Electric rope shovels are one of the most critical assets in open pit mining. They are very large, complex machines with DC or AC motors, multiple reduction gearboxes (some of them complex planetary) and multiple large rolling element bearings. This complexity, combined with the tough 24/7 service, results in too much unplanned shovel downtime, which can affect the entire downstream process."

Jan 1, 2012

By R. R. Bassermann

THE property of Howey Gold Mines, Limited is situated at Red Lake, Ontario, one hundred and seventy-five miles east of Winnipeg and eighty miles north of the Canadian National Railway line. The mine has been a continuous producer since April, 1930, and at present is hoisting 1,350 tons of ore per day. The shaft consists of three compartments (see Figure 1, sketch B). Hoisting is done by two skips in balance, one of which is interchangeable with a cage. Sinking had been carried out at three different periods. From the surface to the 550-foot level, the sets had been spaced at seven-foot intervals, from the 550-to the 1,060-foot level at six feet, and from the 1,060-to the 1,500-foot level at five feet. During the five years of operation, the shaft had become so badly worn, due to spill from the tipples and, to a certain extent, from the loading pockets, that re-timbering was considered necessary. It should be explained that no crushing is done underground because of the ad verse effect this would have on the efficiency of the sorting. The grizzly rail clearance above the ore pockets is fourteen inches and consequently the ore hoisted is extremely coarse. More than average spill from the loading pockets and tipples under such conditions is inevitable, and it is debatable whether underground crushing with consequent increased sorting costs would not be justified. The cost of complete re-timbering according to standard practice would have been prohibitive both directly and indirectly: A lengthy shut-down of the shaft, with the consequent disorganization of the staff and workmen, could not be considered. Accordingly, it became necessary to devise some method of repair that could be carried to completion in a very limited period of time. The shaft timber for the first 250 feet was not in need of repair. From the 250-foot to the 1,060-foot level the wall plates, posts, and blocking were in good condition. These had been protected by a one-inch plank lining put in at various periods during the past three years without interfering with hoisting operations. The end plates and dividers, however, could not be protected in this manner because of the lack of skip clearance. It was decided that, if the dividers in this section could be replaced, the shaft would be as satisfactory as if completely re-timbered. Several factors had to be taken into consideration in deciding on a suit-able method of repair. In the first place, the tipple plates had to be re-designed. To complete the job in a reasonable time, not only had work to be done on the tipple, but simultaneously from several points in the shaft itself. Since all power cables, pipe lines, etc., were in the manway compartment of the shaft, this compartment had to be left undisturbed.

Jan 1, 1935

By A. Shaak

The town of Hedley is some 200 miles due east of Vancouver and lies in the bottom of the Similkameen River valley, at the junction of Twenty Mile creek, at about the 1,700-foot elevation above sea level. The Nickel Plate mine camp is on Nickel Plate mountain at an elevation of about 5,600 feet, four miles slightly east of north from Hedley, to which it is connected by 9 miles of road, and by 10,000 feet of tramway and electric railway. The latter is used both to transport the ore to the 275-ton mill at Hedley and to furnish the mine with supplies. History The Nickel Plate claim was staked in 1898 to cover the sole outcrop of the Nickel Plate system of orebodies. Soon afterwards it was optioned by the Marcus Daly interests of Butte and underground exploration commenced. Early exploration was successful, and a power plant, tramway, and mill were constructed. The mill began operations in 1904. Production under Daly control ensued from June, 1904, to August, 1909, and amounted to 167,000 tons. The Hedley Gold Mining Company was organized and commenced operations in 1909. The capacity of the mill was increased by stages to 200 tons and a steady production, except for short periods in winter, was maintained until 1930. By 1930, gold to the value of nearly $10,000,000 had been produced since the discovery in 1898. The South American Development Company optioned the property in 1932. Active exploration was conducted during 1933 and 1934 by the Kelowna Exploration Company, a subsidiary of the South American Development Company. This work was sufficiently successful that, coupled with the increase in the price of gold from $20.67 to $35.00 per ounce, production re-commenced in December, 1934, and continued uninterrupted until July, i946, when, along with all B.C. gold mines, a strike closed operations. Under the present ownership, the mill capacity was increased to 275 tons.

Jan 1, 1946

By J. D. T. Steyl

"This paper presents a phenomenological model of the rate of iron(III) precipitation in batch and continuous autoclaves at medium temperature operating conditions. The rate expressions are based on information obtained from the literature and experimentation at low and high pulp densities. Special allowance is made for the formation of surface nuclei, which appears to be promoted at a higher iron(III) precipitate surface area, especially in suspensions of lower terminal acidity. This leads to the formation of secondary particulates and provides the required link to simulate high pulp density leaching-precipitation systems, using low pulp density batch precipitation data. In particular, the model allows direct application of the simulation to the autoclave oxidation of iron-containing copper sulfide concentrates and provides a good estimation of the relative precipitation rate of hematite, the preferred product, compared to hydronium jarosite. Some interesting mechanistic understandings of iron(III) precipitation in autoclaves are further elucidated.INTRODUCTIONThe objective of this work is to describe the rate of iron(III) precipitation and the relative amounts of hematite compared to hydronium jarosite precipitation during batch and continuous chalcopyrite oxidation under medium temperature (MT) (~130 to 160ºC) autoclave conditions. Published information has not yet revealed sufficient mechanistic insights about this sparingly soluble salt system under these conditions. The rate expressions in this paper are based in part on current literature information, supplemented by qualitative experimental observation at low pulp density conditions, in particular the high-resolution backscatter electron (BSE) images and particle size distributions (PSDs) of the precipitates. A summary of this work and insights from the literature are presented first, after which the behaviour of iron(III) in high pulp density leaching systems is used to derive a phenomenological expression of the effect of existing iron(III) precipitate surface area on the precipitation rate. The overall regression encapsulates all the experimental results, i.e., those obtained in both batch and continuous autoclave configurations (Steyl, 2012a)."

Jan 1, 2012

By W. Torres Pino, L. Mariscal Samaniego

The Ilo Smelter has been continuously operating since 1960 with Reverberatory furnaces and Pierce Smith converters producing blister copper. The original installed capacity of 1.134 tons per day of concentrated was expanded in 1976. A process of modernization started in 1995 and 1998 with the installation of an El Teniente Converter, a sulfuric acid plant and an oxygen plant to reduce the gaseous emissions to the atmosphere. With the official approval of the Environmental Compliance and Management Program (Programa de Adecuaci6n y Manejo Ambiental - PAMA) in January 1997, Southern Peru Copper Corporation made a commitment to capture 91. 7% of the S02 generated at the smelter by January 2007. After an evaluation of six different technologies, the ISASMEL T process was selected because it can be easily adapted to the present operation, has a lower capital cost and it is a simple process. The fast learning curve to reach the total capacity will allow to fulfill the PAMA commitment in time. The project construction is in process and SPCC is prepared for a successful start-up and transition of the current operations at the end of year 2006. This paper outlines the factors considered by SPCC in its choice of ISASMEL T technology and describes the construction and the start-up activities of the new facilities.

Jan 1, 2007

By A. J. Reed, W. R. Bergey, Carr. J. M.

"The Highmont copper-molybdenum deposits are at Gnawed Mountain in the Highland Valley porphyry copper district, 125 miles northeast of Vancouver. This district is near the center of the lower Jurassic Guichon Batholith, where a north-trending swarm of porphyry dikes is crossed by west-northwesterly structural belts in which fracturing, intrusion of porphyry and breccia, and mineralization areconcentrated.The Highmont deposits are 2 miles southeast of, and in the same southernmost structural belt as, the Lornex deposit. The main deposits occur on either side of a composite dike of granodiorite, porphyry and breccia which strikes west-northwestward in fractured quartz diorite. North of the dike, the adjacent Nos. 1 (East) and 2 (West) zones together contain 150 million tons of open-pit ore mineable in two separate pits. These two zones will support a 25,000-tpd mill with a grade in the first five years of approximately 0.46 per cent copper equivalent. South of the dike, the Nos. 3 and 4 zones are partly explored and will provide large additional reserves. In these various zones, chalcopyrite, bornite and molybdenite form disseminations and fracture-fillings accompanied by quartz, K-feldspar, tourmaline, sericite, specular hematite and other minerals. Bornite extends for varying distances north of the dike, beyond which chalcopyrite is locally accompanied by pyrite. Higher-grade mineralization tends to coincide with fracture swarms, or with shear zones and faults which largely parallel these swarms. The ore zones are reflected by geochemical soil anomalies which show some glacial dispersion. LP. surveys gave weak but significant responses, expressed as per cent frequency effect. The ore zones occur within a strong magnetic gradient, but do not show a significant magnetic response."

Jan 1, 1971

By C. Samuelsson, G. Carlsson

Characterization of dust from Boliden Mineral AB’s copper-plant in Sweden was carried out using chemical analysis, X-ray diffraction analysis, energy dispersive analysis and wave length analysis using electron microprobe equipment. Dust from four different locations was characterized: the electrostatic precipitator (ESP) after the roasting furnace; the ESP after the copper smelting furnace; from the copper converter ventilation bag house filter; and from the bag house filter collecting dust from the settling furnace and tap gas ventilation. The results showed that the dust is composed of small solid and/or liquid particles from the furnace reactor which have been transported with the process gas to the dust collecting devices. This portion of the dust is mechanically formed. It also contains compounds that have been vaporized in the process and then condensed from the process gas at lower temperature, chemically formed dust. The proportion of mechanical and chemical dust varies with the process generating the dust.

Jan 1, 2001

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 N. A. Warner

Virtually zero gas emission smelting is promoted as a means for securing environmental advantages and the general public’s acceptance. Concerns about climate change will increasingly make it more difficult for new primary metals projects to come to fruition unless greenhouse gas emissions are decreased. Assuming a sustainable market for sulphuric acid is not locally available, the next best option is high temperature reaction of strong SO2 with limestone or dolomite. This is followed by CO2 liquefaction and disposal either underground or in the deep ocean. The Voisey’s Bay nickel project is cited as an example where appropriate location of a new smelter close to large dolomite or limestone deposits would lead to a virtually zero gas emission operation. Most of the electrical energy required for producing technically pure oxygen and for liquefying CO2 and transporting it to disposal can be derived from smelting a bulk sulphide concentrate and then reacting SO2 at high temperature. Provided the smelter gases are properly cleaned before sulphur fixation, the sulphated stone should be uncontaminated and environmentally benign and possibly of use in the building and construction industry.

Jan 1, 1999

By G. P. Holmes

"Bell Copper is situated (Latitude 55°0''N, Longitude 126°14W) on Newman Peninsula on the east side of Babine Lake at an altitude of 2,450 feet above sea level. The mine site is approximately 170 miles north west of Prince George and 40 miles east of Smithers. Access to the property is by way of 30 miles of paved road to the Village of Granisle on the west shore of Babine Lake and then a further 9 miles of unpaved road to Bell Copper's west dock. The two mile lake crossing is made using a tug and barge. A compressed air bubbler system maintains an ice free channel for the barge during the winter months.Temperatures range from summer maximums of around 32 °C to winter minimums in the region of minus 40°C. Long periods in winter may be spent with temperatures in the range of minus 15""C to minus 28°C. Freezing temperatures usually start in October and last for six months. The lake normally freezes over in mid December and the ice breaks up in mid May. Snow accounts for approximately two t11irds of the annual precipitation of twenty-one inches."

Jan 1, 1976

By Mory Ghomshei

Pebble Creek Geothermal Power project is associated with a massive recent volcanic eruption in Southwestern British Columbia Canada. Slim holes drilled to depths 1100 m in the prospect area, show very high temperature gradients around 80?100?C/km. The temperature and chemistry of the Pebble Creek hot springs indicate the possibility of a steam reservoir in the prospect area. In addition to high temperature gradients, presence of host rocks with high permeability, along with abundance of recharge waters (from the Lillooet River) provides clear signature of a high-grade geothermal power reservoir at depth 2000 to 3000 m. Data show that over five hundred Megawatt of green power can be generated from the prospect area in a commercially viable manner. The generated power will be base-load, which in comparison with large hydro has the advantage of lower capital costs and a significantly smaller footprint. The final hurdle to overcome, before starting the development phase, is deep exploratory drilling for resource confirmation. This paper is a summary of the data available on the Pebble Creek geothermal power prospect, presented in the context of viability of the resource for large-scale commercial power generation.

Aug 1, 2013