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By E. P. Williams

"Prince Edward Island, Canada's smallest Maritime Province, is located in the southwestern part of the Gulf of St. Lawrence. The Province is more or less centrally located in the Maritimes Basin, a large intermontane basin within the Appalachian orogenic belt. The Maritimes Basin is subdivided into sub-basins and uplifts which exhibit two dominant structural trends: east and northeast. The Basin is known to be petroliferous because of the seeps, shows, oil shales and albertite found in southern New Brunswick and northern Nova Scotia and the gas and oil produced from the Stony Creek field near Moncton, New Brunswick.Permian beds are exposed on the Island, mostly along sea-cliffs. A maximum thickness of about 5,000 feet of red beds -shales, sandstones and conglomerates -make up the sequence. Over most of the Island, the Permian section is much thinner. Four key wells (Mississippian tests) and several shallower tests have been drilled. The Pennsylvanian-Mississippian section thickens rapidly off the Port Hill Uplift at the northwest, where it is less than 4,600 feet thick, and continues to thicken to about 20,000 feet in the Cumberland Basin at the southeast. Geological and geophysical data combine to give us the structural picture of the deeper beds.Prospective reservoir rocks are primarily in the Missis-sippian Horton and Windsor groups. Prospects are:-1. on or over structural highs in the basement; 2. on anticlines or fault highs; 3. over or peripheral to salt domes or salt-core anticlines; 4. at truncation pinchouts of Mississippian prospective beds; 5. in basal sandstone or granite wash on the pre-Carboni-ferous basement; and 6. in facies traps at changes from sandstone to shale or porous to tight carbonate rocks."

Jan 1, 1967

By J. C. White

"This paper was prepared for and presented at a lecture series on ""Materials Randling"" at McGill University. The development of trackless mining at Gaspe Copper Mines, Limited is described, showing the changes in mining method and the part played by the mobile equipment in the evolution of this highly mechanized underground operation. Comparisons of loading and hauling machines are given and an attempt is made to predict some possible future developments.INTRODUCTIONTHE PROPERTY OF GASPE COPPER MINES LIMITED is located in the Gaspe Peninsula of the Province of Quebec, 60 miles west of the village of Gaspe and 25 miles south of the St. Lawrence River. The original discovery of low-grade ore was made at Copper Mountain in 1921. Subsequent exploration revealed the richer Needle Mountain orebodies, and eventually in 1951 the decision was made by Noranda Mines to build the mining, concentrating and smelting complex (Figure 1). Construction and development of the mine was commenced in 1952 and production started in 1955."

Jan 1, 1968

By A. W. F. Smith, P. B. Prangnell, D. N. Crowther, P. J. Apps

It is well known that the refinement of grain size in metals leads to a significant improvement in important mechanical properties. As part of a European collaborative project, processing schedules have been investigated aimed at producing a homogeneous ultra-fine ferrite and spheroidised carbide aggregate microstructure structure in high carbon (CMn) steels (0.6-1.2wt%C), via conventional 'warm' rolling and innovative Equal Channel Angular Extrusion (ECAE). Suitable deformation schedules were determined from dilatometry and thermo-mechanical Gleeble simulations. Evidence of an ultra-fine ferrite and carbide aggregate microstructure following 'warm' rolling is given. A significant improvement in tensile strength, particularly proof stress (0.2%) was also noted in comparison to material deformed at higher temperatures. Concurrent Equal Channel Angular Extrusion (ECAE) experiments investigated microstructural evolution with incremental strain. Extensive analysis was carried out using various techniques, including high resolution Electron Back Scattered Diffraction (EBSD). Evidence of ferrite grain refinement was noted in a eutectoid composition steel. A sub-micron ferrite structure was observed following high strains (E-3.33) and the mechanical properties exhibit a marked increase in tensile strength.

Jan 1, 2004

By Chris Brown

"The Island Copper plant was designed and built by Fluor Utah Ltd, in conjunction with Utah design staff, Originally designed to treat 33,000 tons/day (t/d) of ore, the current average milling capability is 38,000 t/d (Nov'74). The first of six semi-autogenous grinding lines was brought on line in October 1971, startup of the remainder being governed by equipment delivery schedules.The summer of 1973 saw the start-up of an additional three ball mills, and attainment of the present production level. The current process flowsheet is shown in simplified form.CRUSHINGThe crushing circuit is relatively simple, comprising single stage crushing of the ore followed by screening to fine and coarse fractions.The crusher is a 54 x 74in. Allis Chalmers Superior Gyratory with a setting of 9-lOin., driven by a 500-hp motor. Trucks dump on three sides of a rectangular dump pocket. An 84in. x 20ft. link belt apron feeder draws crushed ore from a 250-ton surge bin below the crusher, discharging onto a 72in. wide inclined steel cord conveyor belt. A fixed splitter box at the conveyor discharge separates feed to two parallel Jeffreys 6 x 20ft. vibrating grizzlies for screening into +4in. and -4in. fractions. The fractions are collected on short reversible conveyors which feed the coarse and fine ore stacker conveyors. Trippers distribute ore to outside stockpiles adjacent to, and above, the concentrator grinding 'floor."

Jan 1, 1975

By J. A. Brusset

Introduction The West Canadian Collieries, Limited, operate three bituminous coal mines in the Crowsnest Pass district of Alberta. Two seams are worked; their thickness varies from 10 to 20 feet and their pitch from 10 to 45 degrees. The Bellevue mine was opened in 1903, the Greenhill in 1914; both are gassy and dusty, and at both the haulage is a problem, as the workings are spread over distances of several miles. Compressed-air locomotives are used at Bellevue, rope-haulage at Greenhill, both of which solutions of the haulage problem are costly in installation an operation, and lack flexibility. In 1943, the Adanac mine was opened; and the question soon arose as to which system of haulage should be selected. Compressed-air locomotives and ropes were rejected on the ground of high cost. Since, under the Alberta Mines Act, the use of trolley locomotives underground in coal-seams is not permitted, the choice lay between storage battery locomotives and Diesel locomotives. The preference of the author, who had had experience with both in French gassy coal mines prior to 1930, was for Diesel locomotives, due to lower cost of installation and greater flexibility and reliability. However, Regulation No. 13 of the Mines Act of Alberta reads: 'No gasoline-driven engines shall be used underground in any mine, and no internal combustion engine shall be used underground in any coal mine, except only when authorized by the Chief Inspector in writing, and on such terms as he may prescribe"

Jan 1, 1948

By B. K. Ayres

Modern management of uranium mine or mill waste storage facilities (WSFs) often requires that they be remediated or decommissioned with a cover system. In addition to creating a self-sustaining landscape that supports the end land use, cover systems are intended to reduce long-term risks to human and ecological receptors from the stored waste to acceptable levels. The performance and longevity of a cover system will be strongly influenced by the features or shapes of the WSF final landform. Hence, cover systems and landforms must be thought of as an integrated design. Based on the author’s experience, the most important elements of the design process for maximizing the potential of WSF final landforms / cover systems being sustainable over the long term are noted in this manuscript. Several key items that must be considered and addressed during the planning phase of constructing a WSF final landform are also described. Various methods for monitoring performance of a WSF final landform are also reviewed. Key aspects associated with decommissioning a tailings WSF and waste rock pile at the former Cluff Lake uranium mine in northern Saskatchewan are included to illustrate many of the practical insights provided in this paper.

Jan 1, 2020

By P. Favreau

"This paper describes the progress accomplished at the Noranda Technology Centre in the field of three-dimensional computer-aided underground blast design. Traditional methods of laying out underground blasts are reviewed, and the new computer-aided approach is described. Time savings achieved through the use of BLASTCAD can be advantageously used to better engineer blasts, using models and blast vibration analysis. Future work involving the attachment of blast models directly to the system is also addressed.IntroductionThe Noranda Technology Centre's (NTC) Environment and Mining Laboratory, in cooperation with the mining operations of the Noranda Group, is committed to the development and implementation of new technologies in the field of mineral extraction . Within the frame of its research program, the Blasting Technology Program is developing computer "" tools"" designed to assist the blasting engineer or technician. These computer "" tools"" are regrouped under a global software system called BLASTCAD.The BLASTCAD project started in 1990 at NTC. At that time computer programs designed to calculate and model various blasting parameters had been accumulated. These programs cam e from different sources and were mutually incompatible. Furthermore, they were developed as research programs with tittle effort spent on user interface. These programs are very useful, but are highly specialized, need large input files and can be quite tedious to use as ""standalone"" packages .Therefore, the situation being faced was one where all these programs were available at the Noranda Technology Centre, but not a t the operations. The two following options were then considered: 1. continue to run all the models and programs at the Noranda Technology Centre, and present results through reports to the mines, or2. regroup all the different programs under a single one that would make them share the same data base and be transported to the user. This second option is the one that was adopted; the result is BLASTCAD."

Jan 1, 1993

By E O. Foster

When roasting started at Giant Yellowknife Mines in 1949, it became apparent that, to prevent air and water pollution in the surrounding district, it would be necessary to collect the arsenic that was contained in the exit gases of the roaster. The arsenic collection problem was finally solved by the installation of both electrostatic and baghouse collectors. It was realized that a considerable quantity of gold-bearing dust was leaving the roaster with the exit gases. When the collection problem was solved, it was possible to measure this loss. The loss proved to be considerable and it became evident that a substantial quantity of gold could be recovered. Research programs on dust treatment began in 1958, and by May, 1960, the treatment process which is currently being followed was started in the plant. At present, the two electrostatic preci11itators, Operated at temperatures above 600°F, collect the gold-bearing dust.

Jan 1, 1963

By Sengpasith Houngaloune

Arsenic, which is a toxic and carcinogenic element, causes serious environmental problems throughout the world. It is also known as a major contaminant in the non-ferrous mining and extractive metallurgical industries, thus its disposal is one of the most important environmental issues for the mining and metallurgical industries. In order to ensure a safe disposal environment for the final wastes, stabilization of arsenic has been studied extensively with various approaches. Solidification/stabilization (S/S) represents one of the most effective methods to reduce the availability of arsenic in soil and waste by transforming toxic or potentially hazardous phases into less hazardous ones. Cement based S/S processes could reduce the solubility of arsenic in solid waste, using inorganic binders such as cement, lime, and pozzolanic materials. A new tailings management technique, called cemented paste backfill (CPB), has become widely employed for improving mining techniques and for tailing storage purpose and this technique could also enhance arsenic stabilization, by fixing the contaminants in the binder matrix. Disposal of arsenic in the form of scorodite (FeAsO4?2H2O) has been widely accepted as currently the most suitable method for stabilization and the safest known storage material. The Bio-scorodite process has been reported to be more economic and environmentally friendly method than the chemical crystallization processes. Retention of arsenic by schwertmannite (Fe8O8(OH)6SO4), a metastable ferric oxyhydroxy sulfate mineral, has gained more attention in the recent years. Schwertmannite has a large specific surface area and high capacity to adsorb arsenic in solution. Several researchers have reported that the transformation of schwertmannite to goethite could be retarded by the presence of adsorbed arsenic; therefore schwertmannite might be viable alternative for long-term storage of arsenic. In this paper, various approaches used in arsenic stabilization are reviewed with emphasis on the development in the recent years.

Aug 1, 2013

By James A. Finch, Robert E. McIvor

"This paper presents the development of a new grinding circuit steady-state modeling system. It is fundamentally based on the “functional performance equation”, which has now been used to improve the performance of numerous grinding circuits. This equation characterizes the two distinct efficiencies that are at work in a ball milling circuit, and how these relate to overall circuit productivity. It does so based on the particle size chosen to distinguish between coarse and fine (product size) material. Now, by applying it to all the material size classes, a simple yet reliable ball mill model was created. Combined with cyclone recoveries, the complete, detailed grinding circuit performance can be exactly reproduced mathematically by the computer program. It can then be used with separate process equipment application engineering methods to systematically engineer grinding circuit improvements. The development, features, uses and limitations of the system are described.INITIAL DEVELOPMENT OF THE CIRCUIT MODELThe Functional Performance Equation for Closed Circuit Ball (or Pebble) MillingIt has been shown that closed grinding circuit performance can be effectively characterized by the “functional performance equation” for closed ball or pebble milling circuits (McIvor, 2006a). One method of its derivation is summarized here for convenient reference.First select a cut-off size to define “coarse” versus “fine” or product size material for the grinding circuit. Any particle mesh size can be used to differentiate between coarse material and fines, but the circuit target P80 is often an effective choice for these purposes.Any energy expended on “fines” is wasted. It also generates “extreme fines” often detrimental to downstream processing (McIvor and Finch, 1991). Only the portion of the mill power draw that is expended on coarse material is effectively used. This portion can be estimated from the mill feed and discharge size distributions (McIvor, 1988a) by taking the average of the percentage of “coarse” material in the mill feed and discharge. We can define the thusly calculated percentage of the mill power that is expended on coarse material in the mill as the ball mill circuit “classification system efficiency” (CSEff). The “effective mill power” (EMP) can be calculated from the total mill power (TMP) as follows."

Jan 1, 2007

By L. Price, R. Hortie

Movement of ore and waste from the Hilton Mines pit is accomplished by truck haulage. With the aim of reducing costs, a study of truck fleet replacement was initiated. The study included on-site short-term tests and longer-term rental purchase agreements for haulage trucks. The operation and maintenance characteristics of different trucks, along with projected haulage conditions, were used to prepare cash flows, from which the most advantageous trucks were selected. The results of the study and implementation of the recommendations gave a cost saving greater than had been estimated. The study also indicated areas where improvements could be made, and resulted in much more attention being paid to road conditions, the training of operators and mechanics, and the development of a practical preventative maintenance scheme.

Jan 1, 1971

By Roger J. Higgins

Papua New Guinea is a country on the cusp of development, struggling to find a balance between the demands of national and regional growth, landowner expectations and the maintenance of cultural identity. Ok Tedi Mining Limited is the single largest contributor to PNG?s economy, representing about 10 percent of the country?s GDP. OTML is demonstrating that business and country risk can be managed through effective, respectful partnerships with local communities. OTML?s relationships with the communities of PNG?s Western Province are multifaceted. Communities have borne the brunt of the mine?s environmental impact, yet have benefited enormously from the development that the mine has brought. Importantly, the PNG economy is now the ultimate beneficiary of more than four-fifths of the dividends from the mine, the majority of which are held in trust for long-term sustainable development projects. The paper describes how OTML works with the Western Province communities to create a secure operating environment that recognizes the people?s aspirations for development and self-determination.

May 1, 2002

By Barbara Hendrickson

Outline ? Canadian Regulatory Update ? Turning the Corner: Background & Status ? Implications of U.S. Waxman-Markey bill for Canada ? Federal-provincial considerations ? Current certainties and uncertainties ?Turning the Corner? as Originally Proposed ? April 26, 2007 - the Canadian federal government announced Turning the Corner: An Action Plan to Reduce Greenhouse Gases and Air Pollution (?Turning the Corner?)

May 1, 2009

By Louis R. Bernier

Since 1978, most systematic studies of AMD passive treatment with limestone drains (LD) have dealt with coal mines in the United States. The authors present in this paper the first results of a triennial study initiated in 1999 on the performance of LD installed at the Ni-Cu Lorraine old mine site in Temiscamingue during a remediation plan that involved the installation of a cover with capillary barrier effects (CCBE) over the reactive pyrrhotite-rich tailings. Typically, a LD is a trench enclosed by impervious materials filled with crushed limestone and may be oxic or anoxic. Four LD (one filled with marble and 3 with dolomite) were installed at the Lorraine site. The LD have been in operation since May 1999 and are performing differently. The most contaminated mine effluent flows south and is directed towards 3 LD filled with crushed dolomite, while a 4th LD was filled with crushed marble and installed west. The LD filled with marble has been generating maximum alkalinity since the beginning of the passive treatment. Two of the dolomite drains have been generating alkalinity since mid-summer 1999, but one is not, even if a substantial pH raise was observed. A pH above 5.5 is required usually for the dolomite drains to start generating alkalinity. The installation of LD at the Lorraine site contributes significantly to the reduction of metals and sulphates loading.

May 1, 2001

By A. S. Bayne

WITH the great increase in the use of power-driven machinery in industry, and consequent large-scale operations, the hazards to which , workmen are exposed have become much more numerous than at the beginning of the century. This is especially noticeable in mining. In the past thirty years or so, improvements in methods of excavation and metallurgy have made possible the exploitation of deposits which would have failed to make ore in previous years. This improvement, together with the in-creased use of machinery, has facilitated the mining of tremendously greater tonnages with a marked decrease in unit cost of production. This 'speed up' in mining creates numerous problems demanding close attention of operators and necessitates careful prep;tratory planning, as well as diligent supervision of actual operations. Underground openings increase in size so fast, and all phases of mining, mucking, and transportation proceed at such a rate, that a short period of reduced vigilance on the part of operators . results in disaster, both from the standpoint of safety and economies. Happily, the challenge of increased hazards has been successfully met by a general application of the slogan 'Safety First'. Today, we have large manufacturing concerns devoted entirely to the development and production of safety equipment for the protection of workmen in various branches of industry. Machinery manufacturers, in co-operation with their mining customers, have included the best possible in foolproof devices in the manufacture of hoists, compressors, boilers, electric motors, and equipment of all kinds. Mining companies and private individuals spend thousands of dollars and devote a great deal of time to research with the single object of preventing accidents and combating miners? diseases. Governments throughout the world have written regulations into their statures for the protection of miners and operators. Staffs are appointed to enforce these laws and investigate accidents to ascertain means of preventing them for the future benefit of the industry.

Jan 1, 1938

By Michel Jébrak, Claude Bellehumeur

Abstract - Regional and orientation geochemical stream sediment surveys were carried out by the Quebec Department of Energy and Resources in southwestern Quebec, over a part of the Mont­ Laurier Terrane of the Grenville Province. The area contains some small stratiform zinc deposits. The response of Zn mineralization to geochemical surveys is weak; the known mineralization is not defined by anomalous samples and consistent patterns. This study uses a technique that increases the geochemical signature of Zn mineralization in filtering out geochemical background components related to lithologies and surficial conditions. The background variations were modelled using principal component analysis, and the filtering technique consists of the partial reconstruction of the data matrix from results of principal component analysis . The filtering procedure considerably enhances the Zn anomalies located in the catchment basins of Zn deposits, and defines some new anomalies in proximity to the marbles of the Mont-Laurier Terrane, the principal metallotect of Zn mineralization.

Jan 1, 1993

By J. A. McCamley

Gypsum scrap generated from wallboard manufacturing, construction and deconstruction activities in North America, Europe and Japan is a recognized environmental problem. Landfill disposal of this gypsum scrap is problematic, with deposits often creating hydrogen sulphide emissions and metallic sulphide groundwater leachates. Of these regions, Europe is the most advanced in dealing with the issue having enacted legislation, which will come into effect in July 2005 that will strongly encourage gypsum recycling throughout the EU. An estimated 10% to 17% of all gypsum used in the wallboard industry becomes recyclable scrap, which represents approximately 1% of the total waste stream in North America. In the United States, 2.5 to 4.5 Mt of gypsum scrap is generated each year; the volume is similar in Europe (the percentage of total tonnage is less because of the higher use of brick and concrete). The Greater Vancouver region of British Columbia has banned gypsum from its landfills, and as a result, all gypsum scrap is now recycled. New West Gypsum Recycling, a Canadian firm, uses its proprietary technology to process large quantities of gypsum scrap that is reincorporated into new wallboard, at percentages ranging up to 25%. The operation of New West Gypsum Recycling Inc. of Langley, Vancouver is examined as a case study and recommendations are provided as to how other urban regions can implement similar gypsum scrap recycling programs.

Jan 1, 2004

By N. Parnian

"Carryover of caustic soda (NaOH) in the steam path caused catastrophic failure of superheater 304H stainless steel tubes in a steam generator and led to an unexpected shutdown after just five months of continuous service of petrochemical following the start of production. The cause of the failure was studied, with a focus on the formation of sigma phase in the weld joint and effect of caustic embrittlement on stress corrosion cracking (SCC). The cracks were examined at the seam weld, heat affected zone (HAZ), and Ubend areas. Hardness was measured for the base metal, HAZ, and weld metal, and microstructures were examined using optical microscopy and scanning electron microscopy (SEM). Crack initiation is attributed to gouging on the precipitated carbide at the HAZ and also the formation of sigma phase in the weld metal, as shown by energy dispersive X-ray (EDX) analysis. In addition, cracking was propagated by caustic embrittlement because of residual stresses and hammering. Finally, the characteristic feature of fracture was illustrated by SEM fractography, and consists mostly of intergranular SCC and some quasicleavage transgranular. INTRODUCTIONThree key factors are needed for the initiation and propagation of intergranular stress corrosion cracking (IGSCC): a susceptible material, a corrosive environment, and sufficient stress. Although austenitic stainless steels are susceptible to sensitization and IGSCC, they are widely used in boiler and superheater tubes because of their high corrosion resistance, high oxidation resistance, acceptable mechanical characteristics at elevated temperatures, and low cost.Sodium hydroxide is injected to neutralize acidic constituents in the steam path, but caustic can concentrate in boiler tubes and attack the surface metal (known as gouging) even traces of caustic in the steam can deposit on surfaces and cause local concentrations of several percent (ASM handbook, 1992). Not only sensitized grains but also sigma phase formed in the weld metal can initiate caustic cracking. In this research, the cause of the failure of 304H stainless steel superheater tubes in a methanol petrochemical plant in Iran was studied with a focus on the effects of caustic embrittlement on IGSCC."

Jan 1, 2012

By M. H. Pettibone

Sohio Petroleum Company's new L-Bar uranium mill near Grants, New Mexico. refines 2722 kilograms of yellowcake daily from 1360 metric tons of ore produced at Sohio 's J.J. No. 1 mine and other nearby mines. This paper follows the ore from the mine through the various processing steps - semi-autogenous grinding, acid leaching , countercurrent decantation, solvent extraction , ammonium diuranate precipitation, washing and drying, and tailings disposal.

Jan 1, 1978

By P. Favreau

This paper describes the progress accomplished at the Noranda Technology Centre in the field of three-dimensional computer-aided underground blast design. Traditional methods of laying out underground blasts are reviewed, and the new computer-aided approach is described. Time savings achieved through the use of BLASTCAD can be advantageously used to better engineer blasts, using models and blast vibration analysis. Future work involving the attachment of blast models directly to the system is also addressed.

Feb 1, 1993