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By R. C. Lo, M. D. Scott

"This paper reviews tailings management at Highland Valley Copper, and outlines main features of its tailings storage facility enclosed between the H-H and L-L dams. Key management focusses are: energy efficiency, cost effectiveness, safety and integrity of the tailings impoundment, environmental protection, and reclamation after decommissioning. Main features of the tailings facility include: high international standards for seismic and flood design criteria, water management and water quality monitoring, operations and construction optimization, reclamation and decommissioning plan, and geotechnical challenges associated with the complex geology of the L-L tailings dam foundation.IntroductionHighland Valley Copper stores its tailings mainly in the Highland Valley tailings facility (ultimate capacity: 1.8 billion tonnes). Smaller tailings storage facilities were operated by predecessor companies: the Number One Pond, the Trojan Pond at Bethlehem and the Highmont Pond at the Highmont operation as well as backfilling the Heustis and Jersey lona Pits at Bethlehem. These areas are currently not in use, and are in the reclamation phase prior to decommissioning. This paper focusses on tailings management in the main facility. As indicated in Figure I, the facility includes three tailings dams: these are, going from east to west, the H-H, J-J and L-L Dam, named after the alignment alternatives in the initial feasibility studies. From 1970 to 1977 Canadian Bechtel Ltd. advised Highland Valley Copper's predecessor company Lornex, on tailings storage at the H-H and J-J Dams and on the L-L Dam. Since the completion of the L-L Starter Dam in 1977, Klohn Leonoff Ltd. has provided ongoing consultation and construction monitoring of the raising of the L-L and the H-H Dams. The J-J Dams is currently buried by deposited tailings. This paper reviews key tailings management focusses and main features of the tailings facility."

Jan 1, 1992

By Robert B. Wickham

"American Barrick has always balanced its aggressive operating approach with a conservative financial strategy. In fact, what enables their mining team to pursue such aggressive plans with confidence is the conservative financial strategy adhered to by the company. These policies are built on a prudent mix of gold linked financings, equity and gold price hedging.This paper outlines these policies and focusses in particular on American Barrick's gold price hedging program.IntroductionThe company's balance sheet at the end of 1990 clearly shows the wisdom of its conservative policies. Total assets have grown to over US$1 billion; cash has grown to US$312 million and shareholders' equity to US$645 million. All amounts included in this paper are quoted in U.S. dollars. Increased gold production and an effective gold price hedging program also combined to produce record income from operations, earnings and cash flow in 1990.The first half of 1991 is also indicative of the benefits of the company's conservative financial policies. Increasing production, together with its comprehensive gold hedging program, has generated increased earnings, even in a period of falling gold prices.All year-over-year numbers for the first six months are up. Gold production was 36% higher; earnings of $40.2 million $ 0.30 per share - were 46% higher than 1990.Barricks revenue continued to increase despite gold prices remaining unchanged during 1990. Barrick's hedging policy protects the company from falling gold prices on the basis that the upside looks after itself. Their hedging program - including various goldlinked fmancings - enabled Barrick to realize an average price of $437 per ounce of gold sold in 1990, compared with the Comex average gold price for the year of $384 per ounce."

Jan 1, 1991

By M. P. Brameld, R. H. McCorkell

"Overburden covering bedrock uranium deposits was sampled to depths of 29 m and Rn concentrations measured at the same depths. Total-alpha activities, V concentrations and Rn emanation (J) of the samples were measured. The U-flux into the overburden was greater in the past: oxidation and dissolution has since removed most U, leaving decay products which indicate the presence of U deposits when U itself does not. Distributions of U and decay products and their ratios to each other reflect U-migration and degrees of U-removal. Rn distribution in overburden is related to the J of overburden samples and the presence and movement of groundwater. Simple, rapid methods of total-alpha and J measurement are described.IntroductionThe overburden drilling apparatus developed by Bondar-Clegg and Company makes possible sampling and radon measurement in overburden from the surface down to about 50 metres. This apparatus was used here to study the diffusion of uranium and its decay products from ore deposits into over lying overburden at the N deposit of the Amok Ltd. property (Cluff Lake, Saskatchewan) and on the Imperial Minerals Ltd. property at Gooderham, Ontario. These ores are enclosed in bedrock; the overburdens were deposited by glaciers or streams. The migration of uranium and its decay products in such situations and the factors which affect it have been little studied in the past, as readily usable techniques for mapping it in three dimensions have not been available. The results reported here are somewhat sketchy and preliminary, but they indicate the value of the methods used and some of the patterns to be expected. Surface and subsurface sampling and measurements were carried out on 3-line grids crossing known zones of mineralization. The lines were 60 metres apart at Gooderham and 40 metres apart at Cluff Lake."

Jan 1, 1982

By N. Dufresne

"The evolution of mining methods at Brunswick Mining and Smelting shows that, in the case of a large deposit, technology must adapt itself to changing conditions. As problems are encountered, management must modify their approach if they hope to meet production quotas. This search for new and better ways started with the opening of the No. 12 orebody and is still going on today.From large-scale open stoping, the Brunswick Mining and Smelting operation went to transversal cut-and-fill, then to longitudinal cut-and-fill, which is the main mining method now employed. However, to solve certain problems experimenting with Avoca methods was initiated. Rebar grouting and prepinning have also made significant contributions toward securing relatively poor ground in the hanging wall and holding badly fractured backs in wide stoping areas. Introduction In 1952, M.J. Boylen had incorporated Brunswick Mining and Smelting Corporation Limited to develop his recently found No.6 and No. 12 orebodies near Bathurst, New Brunswick. Between 1953 and 1957, St. Joseph Lead Company was brought in to try and initiate mining . During those years, St. Joseph Lead sunk two shafts at No. 12-No. 1 to 425 feet below surface and No.2 to 982 feet. They also developed the 200 and 350 levels to sample the ore at depth and operated a 100-tpd pilot plant at the No.6 mine. However, due to low recoveries and depressed metal prices. the project was shut down in 1957.A group including M.J. Boylen. K.C. Irving. Maritime Mining Corporation and Patino Corporation reacquired the property from St. Joseph Lead Company in 1961. New financing was arranged involving La Societe Generale des Minerais, S.A . of Belgium and Engineering Consultants Limited of Saint John. New Brunswick. During the years 1962 and 1963, construction of surface and underground facilities progressed rapidly."

Jan 1, 1981

By M. J. Gole, R. E. T. Hill, S. J. Barnes

"The Agnew (also known as the Perseverance) nickel deposit and its northern extension, the Rocky's Reward deposit, form one of the world's largest accumulations of nickel sulphides hosted by komatiites. Agnew was previously classified as an ""intrusive dunite-associated"" deposit . It has now been shown that the sulphides are hosted by komatiite flows which underlie an adcumulate-textured dunite body that crystallized in a large lava channel.The rocks of the mine area have been subjected to a metamorphic temperature of550°C and pressure of up to 3 kb. The komatiites have mostly been reconstituted to olivine-amphibole chlorite assemblages. There is a zoned sequence of enstatite-, anthophylite-, talc- and antigorite-bearing assemblages inwards from the western margin of the ultramatic reflecting variations in the CO/HP ratio of metamorphic fluids.Facing directions are determined from variations in the proportions of metamorphic minerals and in rock compositions which reflect asymmetric layering in the flows . Olivine-sulphides matrix ore is hosted in a single 50 m thick, east-facing flow that is overlain by flows containing massive sulphides. Much of the massive sulphide has been physically remobilized into fold noses, faults and shear zones. Chemical diffusion of ore components has upgraded a sulphide-rich metasedimentary unit where it is in structural contact with massive ore.To the north, the mineralized flow sequence is separated from a stratigraphically higher komatiite sequence, the Perseverance ultramafic complex, by approximately 150 m of felsic meta volcanic and meta sedimentary rocks. Southward, the Perseverance ultramafic grades laterally into an olivine adcumulate body and its lower contact cuts progressively down stratigraphy until it lies directly on top of olivine-sulphide ore of the mineralized flow sequence. This discordant contact is interpreted as the base of a thermal erosion channel formed by a voluminous komatiite lava flow. This contact greatly influenced later deformation of the mineralized flow sequence."

Jan 1, 1989

By Anthony P. Makuch

Dynatec Corporation is an integrated mining services company, providing mine development, operations management, engineering, drilling and metallurgical services to the North American mining industry. Dynatec was the contract operator of the Ken Snyder Mine in Midas, Nevada from start of production in January 1999 to September 2001. This paper summarizes Dynatec?s experience and approach to the use of longhole stoping methods for mining to widths of 1.3 to 2 metres in a steeply dipping narrow vein orebody.

Oct 1, 2001

By S. C. Livanou, S. P. Tampouris, E. N. Zevgolis

In ferronickel (Fe-Ni) production from oxidized nickeliferous ores, mechanical losses of ferronickel in the slag are reduced by magnetic separation. Slag from the electric furnaces (E/Fs) contains 0.16% Ni. Its magnetic separation gave a pre-concentrate with 0.76% Ni, weighing approximately 6.5% of the feed. Nickel recovery was 29.7%. This pre-concentrate was then treated in a second (concentration) plant. Concentration treatment involves screening, crushing and magnetic separation. A pre-concentrate with 0.76% Ni gave a magnetic concentrate with 2.58% Ni and a non¬magnetic part with 0.35% Ni. Smelting of the non-magnetic part without the addition of a reduction agent in a laboratory electric arc furnace, gave a ferronickel alloy with approximately 20% Ni and a slag with 0.16% Ni.

Jan 1, 2005

By M. Bozorgtabar

Metal Matrix Composites (MMC) have a ductile matrix containing ceramic particles, Due to their improved wear properties, Al?SiC composites have economical applications in many industrial uses where wear is a problem, One of the most serious difficulties in manufacturing Al-SiC composites is obtaining adequate 'wetting' of the particles by the melt. In this research work, a stir casting system was designed for the improved manufacturing Al-SiC composites, The effect of some production variables such as the addition of SiC particles to the aluminum melt on wettability, was also studied. The results showed that the manual addition of particles would not be successful in manufacturing and that a system of adding silicon carbide particles through controlled temperature, atmosphere and improved mixing was needed.

Jan 1, 2005

By B. R. Conard

Occupational epidemiology of the nickel-producing industry has found that inhalation exposures to certain nickel-containing substances are linked to respiratory cancers and to nonmalignant respiratory endpoints. Establishing such a linkage, however, is complicated by the fact that some diseases occur long after exposure to a causal agent (i.e., some diseases have long latencies). Furthermore, most chemical agents (especially nickel substances) vary significantly in their toxicological properties and their concentrations in workplace air have varied over processing history. Because of these complications, it is critical to understand historical exposures to specific nickel substances. To assist in this effort, the author focuses on the history of smelting and its related processes at Vale Canada’s (Inco’s) Ontario operations in the first half of the 20th century.

Jan 1, 2012

By James E. Wennen

The through-put and energy efficiency of an autogenous (AG) grinding mill are adversely affected by variability in rock size and rock competency. This applies to both fully autogenous and semi-autogenous (SAG) grinding circuits. In this paper we focus on an approach to overcome the problem of inconsistent mill through-put related to variability in mill feed size and rock competency. The focus is on ores containing hard, competent rock. This approach consists of preparing feed to an autogenous mill that contains 20% coarse media rock and 80% of material crushed to pass 37 mm. Results of pilot-scale testing for two iron-ores will be presented to show that a 10% to 12% reduction in unit energy consumption is possible with prepared feed, compared with feeding the mill with conventional primary crusher discharge.

Jan 1, 2012

By M. P. Rennick, D. M. Burton

Abstract -The Murray Brook massive sulfide deposit, which was the first geochemical discovery in the Bathurst camp, is one of the largest sulfide deposits in the area. The massive sulfides are hosted by quartzose metasedimentary rocks in the lower part of the Ordovician Tetagouche Group. This thick succession of sedimentary rocks is overlain conformably by felsic volcanic rocks, and is structurally overlain by mafic volcanic rocks. The massive-sulfide body is polydeformed, but primary metal zoning is still discernable and may permit future exploitation of discrete lead-zinc and copper zones. Although it was discovered in 1956, the deposit was not developed unti11989, when Murray Brook Resources commenced processing of gossan containing precious metals. Recovery of gold, silver, and mercury is accomplished by indoor vat leaching on a year-round basis.

Jan 1, 1992

By K. D. Bulin

"An interesting brief history review of shovels as the primary excavating tool will permit the reader to see that immeasurable development and resources have preceded the shovel excavators which today are used extensively throughout the mining industry. With this as a background, the shovel manufacturer has the ability to utilize his resources best in those areas of shovel development in which the maximum benefits of increased reliability, performance and ease of maintenance will improve the operating rewards to the user of the equipment. The author explains the function of the shovel as a part of the material handling system. A detailed description of those areas of the shovel in which the most recent developments and major improvements have been implemented in the manufacture of the shovel excavator arc included."

Jan 1, 1973

By A. Michalkow

DELN ITE Mines Limited is located in Deloro township, on the west end of the south break of the Porcupine Camp. Mining operations are currently being carried out on the downward extension of a system of quartz veins in an andesite zone. This zone has been followed from surface to the present bottom level of 5,250 feet. The changing mineralogy of the vein system has involved an increase in tourmaline content from the surface downwards, so that the veins at the lower levels are composed of dark brown quartz-tourmaline. The drilling problem presented by these extremely hard veins was partially alleviated by the development and adoption of a one-inch drill bit. All blast-hole drilling is now done with the one-inch bit, without any difference in hole spacing.

Jan 1, 1962

By C. J. Sullivan

It is of importance, in prospecting, to distinguish ores of magmatic origin from those derived by the meta-morphism and granitization of source rocks and from those accumulated in certain sedimentary facies. The magmatic ores, which are characterized by their occurrence along fault structures, may be associated with volcanic (including explosive) phenomena. Heat effects are local. The magmatic sequence is well de-fined: kimberlite, with diamond pipes; ijolite, with carbonatites; peridotite, with nickel deposits; norite, with nickel-copper deposits; and diabase-gabbro, with copper-zinc deposits. These deposits are characteristic of Precambrian shields, where a thick sialic crust may rest on basic to ultrabasic magma. The sequence is resumed in the Paleozoic terrains (in a broad sense), with monzonite porphyries and associated copper, copper-gold, and cop-per-lead-zinc deposits.

Jan 1, 1962

By E. W. Coderre, R. C. Baxter

"This paper describes the townsite of Wabush and the two railways operated by Wabush Mines for the loading and unloading of iron ore concentrate. The town of Wabush is located approximately 200 air miles north of Sept-Iles, Quebec and is in the Province of Newfoundland and Labrador. Construction of the town-site began in 1961 to provide housing accommodation for the construction force and permanent employees in the mining and milling operations located 4 miles away. Wabush Mines operates two short railway lines in loading and unloading concentrate between the concentrator, located at Wabush, and the pellet plant at Pointe Noire, Quebec. Both of these railways connect with the main line of the Quebec North Shore and Labrador Railway and provide a shuttle service between the two phases of the operation."

Jan 1, 1969

By K. G. Stowe

"1. Introduction Mattagami Lake Mines and Orchan Mines operate zinc copper mines adjacent to one another near Matagami, Quebec, situated approximately 300 kilometres north-east of Rouyn-Noranda. (Note: Mattagami Lake and Orchan are in the process of being absorbed by Noranda Mines and will become Noranda Mines-Matagami Division). Both concentrators began operations in late 1963.The Mattagami Lake concentrator is capable of treating up to 3,500 metric tons per day of massive sulphide ore with a mineral composition shown in TABLE 1. The Orchan concentrator consists of two separate circuits - the Orchan circuit with a capacity of 1,050 metric tons per day and a custom circuit with a capacity of 825 metric tons per day. Throughout its operation, Orchan has custom milled ore from several smaller deposits in the Matagami district."

Jan 1, 1979

By H. Henein

Atomization provides many advantages in processing such as rapid solidification and near net shaping. Two atomization techniques will be compared and contrasted in this presentation: Single fluid atomization techniques such as Impulse Atomization (IA) and gas atomization. The characteristics of both processing approaches will be presented. Results in powder structure, size and size distribution as well as microstructure will be discussed. A comparison of spray formed ingots carried out using both techniques will also be presented.

Jan 1, 2007

Planning and operational problems Difficulty in getting accurate geological interpretation Hard to plan work in advance Constant changes in engineering drawings and specifications Occasionally, a small stope portion requires changing the mining method from room-and pillar to shrinkage The ground has to remain stable until the entire stope is mined out A large stope portion is mined as development (30%) Frequent corrective excavation work due to dip changes Unstable and inclined working surface Frequent rehabilitation work is required

Feb 1, 2008

By Selwyn G. Blaylock

I.-THE HISTORY OF THE SYSTEM TO trace the history of the development of the Co-operative Committee System in The Consolidated Mining and Smelting Company of Canada, Limited, one must look backward about twenty years. In 1915 and 1916, the first years of the W ar to really affect Canadian life, there were sixteen hundred men working in the Trail plant. These men were, on the whole, a splendid body of men and pa trio tic to the core. They were almost one hundred percent organized, ninety-five percent of them be-longing to the Union of the Western Federation of Miners. Most of the tradesmen belonged to their craft unions as well. For example, there were ? local machinist, steel workers', electrician, boiler maker, bricklayer, and carpenter unions. The Company had always maintained an open-shop policy and refused to enforce membership in any union, but recognized the right of every man to belong to unions. The only exceptions have been the I.W.W. and the One Big Union. Both of these organizations have always been fought by the Company. By 1916, membership in the Western Federation being practically 100 per cent, the Company recognized this organization's authority to make agreements, and a wage and hour agreement was drawn up and signed by the Company and the local officials of the Union, and ratified and signed by the Head Office of the Union in Denver, Colorado. This agreement was for the duration of the war.

Jan 1, 1936

By J. J. McDougall

Until quite recently, the coal in the Cape Breton field was won from comparatively thick seams with light cover, and from submarine areas, and the system of mining naturally followed was pillar-and-stall. This sytem permitted of cheap extraction, and enabled production from localities where other methods could not be employed to good advantage. Thus the pillar-and-stall system, applied to conditions as stated, justified its adoption. Our working seams today, however, are practically all under heavy cover, or are moving in that direction, and with this gradual increase in cover came the increased cost of roadway maintenance. At Princess colliery, the system of pillar-and-stall was followed until roof and bottom conditions became such that further operations were unprofitable, and the longwall method was then adopted as an economic necessity. This fact should be borne in mind when operating costs of both systems are being compared. The longwall method is not held as a cure for all difficulties of heavy cover, but through it these difficulties can be overcome with less expense than by pillar-and-stall. The longwall system of mining, strictly speaking, is one by which a seam of coal is totally extracted in one operation. There are, however, many modifications of longwall, and in some cases it is difficult to determine whether certain practices should be classed as longwall or pillar-and-stall, or a combination of both.

Jan 1, 1928