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By Robert B. Parsons

"Ontario and Quebec taxpayers will have to dig deeper into their pockets to pay more tax, according to budget papers tabled in these provinces in May 1993. Individuals will be hardest hit, but corporations will also have to ante up in the face of higher rates, reduced deductions, and new taxes.Up, up, and away...Somewhere in the bleak picture of the 1993 Quebec and Ontario budgets, there is a bit of good news for the mining industry.Careful scrutiny reveals:• Ontario will correct a capital tax provision which inadvertently penalizes flow through share issuers;• Quebec's flow-through incentives will be extended to December 31, 1995; and • both Quebec and Ontario will allow deductions for mine site reclamation payments.The industry may also find some comfort in the fact that Ontario's new corporate minimum tax will be profit-based (unlike the federal minimum tax), so that non-producers should not face a liability for this tax. There is some concern though, about Quebec's announcement that the refundable credit mechanism in the Mining Duties Act will be reviewed."

Jan 1, 1993

By Andre Vien, D. H. Hendriks, D. Willet, B. C. Flintoff

"For many years the training of mill operators was an informal process which involved senior operators training junior operators on an as-needed basis. Recognizing the needs and benefits of better training some companies, and even some provinces through legislation, have moved to ensure that a formalized training program exists in the plants. These programs tend to focus on basic safety and operations. Much remains to be done. With the more rapid incorporation of new processing and information technologies, and the goal to keep labour costs to a minimum by doing more with less, operator training has become a critical issue. This paper briefly examines the evolution of training programs, provides some measure of their effectiveness, and explores some recent developments which could have a very significant impact on the industry.PreambleOne can draw an analogy between operator training and the mechanical support of production equipment. When we buy a piece of process equipment it is critical that the mechanical installation be done properly to ensure that the device will operate at peak performance on start-up. Once the equipment is running, some form of preventive maintenance is required to ensure continued efficient operation. The operators and the equipment are both elements of the processing system, yet the former do not seem to get the same ""start-up"" or ""operating"" support. Are they not seen as critical to efficient operation? Why is this so? What impact does it have? How can we improve?These are all very logical and important questions, although the answers are not nearly so obvious. In the mineral processing industry, progress in operator training over the past thirty years has been limited and quite variable. To address the perceived need for a more coherent and consistent approach, some provinces have moved to incorporate basic training requirements in their legislation. Some plants have gone a few steps further by building integrated training programs into their operating culture. One conclusion which can be easily reached is that there are no standards, and that the range of training activity is great. In other words, a flotation operator is not a flotation operator is not a flotation operator. Their knowledge and skills are very much a function of training and experience, which are clearly corporate and site specific."

Jan 1, 1994

By R. J. Labine, D. I. Brisbin, R. Roussain, P. R. Coad

"Abstract - The Owl Creek Mine is located near the west end of the Neo-archean Abitibi greenstone belt, 17 km northeast of Timmins, Ontario, and 4 km north of the Destor Porcupine fault. Gold occurs in epigenetic quartz veins and their pyritic wallrocks in two zones within a package of east striking, steeply north dipping, volcanic and sedimentary rocks. At the West Zone, 1 729 603 t of ore with a grade of 4.83 g/t Au (268 587 troy oz.) were produced from an open pit centered on a wedgeshaped unit of Tisdale Group basalt that occurs between two overturned, south facing units of Porcupine Group graywacke and argillite. Basalt/graywacke contacts are locally marked by graphiticcarbonaceous argillite, strike-parallel faults and massive quartz veins.Deformed quartz+/-ankerite veins occur along the graphitic sedimentary/volcanic contacts and in gently to moderately dipping fractures in basalts, and, to a lesser extent, in graywackes. Veins also occur sub-parallel to steeply dipping 070° foliation. Altered host basalts are composed of iron carbonate, sericite, quartz, carbon, chlorite and disseminated pyrite. Gold occurs as inclusions in pyrite, and less commonly as free gold in fractures and along graphite-quartz grain boundaries in quartz veins. Fractures preferentially developed in more competent basalts during pre- to syn-ore deformation are interpreted to have provided the permeability required for emplacement of mineralized quartz veins. Carbonaceous basalt/graywacke contacts further enhanced gold deposition by acting as chemical traps. The interaction of hydrothermal fluids with these carbonaceous sedimentary rocks led to the characteristic local darkening of host basalts due to carbon impregnation and chlorite development."

Jan 1, 1998

By H. N. Tran, D. Barham

"A systematic survey of the appropriate literature in terms of phase equilibria and possible reactions involving deposits in Municipal Solid Waste (MSW) incinerators are analyzed particularly with respect to the theoretical first melting points of typical ashes and the possible presence of a liquid phase at the temperature of ash-metal interface. Conclusions are drawn on the basis of the possible presence or absence of various metal chlorides and sulphates in such situations, and their effects on the problems of fouling and metal corrosion. From preliminary results, it would appear that ZnCl2 is unlikely to be present in any molten phase which causes corrosion because it evaporates rapidly from such liquids. It would also appear that PbCl2 and, by inference, ZnCl2 will sulphate at relatively low temperatures if the flue gas contains SO2 and O2.IntroductionMunicipal Solid Waste (MSW) incinerators produce fly ash which deposits on heat transfer surfaces throughout the furnace, leading to corrosion and loss of energy recovery efficiency. Despite a massive amount of research carried out on the subject of corrosion in MSW incinerators, the problem of corrosion of heat transfer metal is still with us, and no definite over-all cause and effect relationship has yet been identified. In order to make a contribution to the eventual solution of this problem, the authors have examined the problem from the beginning, using their knowledge of fouling and corrosion problems in black liquor recovery boilers as a starting point.The incineration of MSW has been used for many years to reduce the volume of material sent to landfill (ash volume compared to raw waste volume), and, in most cases, to recover energy at the same time by raising steam The steam may be ""low- or high pressure/ temperature"" depending on its end use. The higher the steam pressure and temperature, the greater seem to be the problems with corrosion of heat exchanger metal, presumably because the metal must withstand higher surface temperatures.The chemical and physical composition of MSW is extremely variable, not only on a regional basis, seasonal basis, and day-today basis, but also on a minute-by-minute basis, due to the inhomogeneity of MSW. This makes it extremely difficult to define cause and effect relationships, because both cause and effect are transient in nature."

Jan 1, 1991

By J. B. Sabey, V. R. Degner, D. MacGillivray

"Hydrodynamics principals are applied to the design of a natural air ingestion flotation machine for coarse solids applications. Preliminary laboratory test data and subsequent operating plant flotation kinetic performance evaluations are reviewed. INTRODUCTIONThe concentration of potash (sylvite, KCI) from halite and other salts using flotation is well understood and practice a with much success. Reagent schemes and plant circuitry for obtaining the desired product recovery and grade have been established with proven performance. These flotation circuits normally process the medium and finer size particles, less than 30 mesh (600 microns).However, often the potash market trends specifically demand a coarse product size. This emphasis, accompanied by the existing high losses of coarse (+30 mesh) potash in flotation circuits, creates the need for development of a flotation machines specifically designed for coarse potash beneficiation.This technical challenge was undertaken by the WEMCO Research and Development Group. The specific objectives of this flotation machine development program were ( l) to achieve an ""Ultra Coarse Flotation Machine"" capable of adequately suspending and transporting particles in the 4 - 30 mesh (4.75 - 0.6 mm) size range at solids concentrations of 30% or greater and (2) ascertain metallurgical performance of this machine.This paper covers the development (both theoretical and mechanical/ hydrodynamic), the field test program and results, a discussion of applicable flotation kinetics, and conclusions of this ""Coarse Potash Flotation Machine"" development project."

Jan 1, 1986

By T. G. Carter

"This paper traces the introduction and use of fire-resistant (FR) fluids in hydraulic systems at underground mines in British Columbia. Reasons are given for the decision to make compulsory the use of such fluids in underground mines after January 1, 1975 by provincial government legislation. Examples are quoted of fires caused, or supported by, mineral oils which have resulted in loss of life and property.The basic principles of hydraulic systems are reviewed in order to present the effects of changing a system operating on mineral oils to one which must operate on FR fluids. Approximations of the cost of system conversions are given for certain machines and a brief survey is made of the various pieces of underground equipment which contain hydraulic systems operating on FR fluids.IntroductionIn 1948, Admiral Ben Moreel , who was then president of Jones and Laughlin Steel Corporation in the United States , wrote:""Although safe and healthful working conditions can be justified on a cold dollars-and- cents basis, I prefer to justify them on the basic principle that it is the right thing to do. ""(1)This paper will outline the introduction and use of fire resistant fluids at mine operations in the Province of British Columbia. That it was the right thing to do in enhancing the safety and well-being of every person employed at the mines was the prime consideration. That it may be justified on a cold dollars-and-cents basis is left for the reader to judge. The prime purpose of this paper is not so much to trace the efforts made by the individual mines to successfully introduce and use fire-resistant (FR) fluids in hydraulic systems, but to present an over-all picture of what occurred, in a collective sense, at the majority of mines which have ended up with a working FR fluid system. The problems attendant to the introduction of an FR fluid will be recounted in a manner which, it is hoped, will prove useful to those contemplating system conversions. Because the predominant fluid now in use is an invert, or water-in-oil. emulsion, this will be the FR fluid considered.Fluid Loss from SystemsThe quantities of various fluids required for use in hydraulic systems are extremely high. This statement in itself may appear to be redundant in that the capacities of the various systems should demand that a fixed amount of fluid is required for the initial filling of a system, with a further amount of fluid scheduled for use during subsequent fluid changes, i.e. at the recommended change intervals . If only this were the case!"

Jan 1, 1981

By J. W. Griffith

"The mines in the Bancroft area of southeastern Ontario, a few kilometres west of the town of Bancroft, are in Faraday and Cardiff Townships. Three companies, known as Canadian Dyno Mines Limited, Macassa Gold Mines Limited (Bicroft Division) and Madawaska Mines Limited (formerly Faraday Uranium Mines Limited), with plants capable of handling a total of 4,()()() tons (3,629 tonnes) of ore a day, were at one time in production. A fourth company, Greyhawk Uranium Mines Limited, operated a small mine whose ore was shipped for custom treatment to the nearby Faraday mill. Canadian Dyno Mines Limited ceased operations in June 1960. In June 1963 the Bicroft Mine was closed and a year later Faraday closed because of contract completion. But in 1975, Faraday (now called Madawaska) was re-opened but closed again in 1982. During 1959, the peak year, these four mines produced an estimated 1,100 tons (998 tonnes) of uranium precipitates, which represented nearly 7 per cent of Canada's output for that year(Fig. 1).The deposits occur in pegmatitic granite dykes in a region of high-grade metamorphic and metasomatic rocks. Uranium distribution is usually controlled by the distribution of mafic minerals, particularly hematite and magnetite, and by late fractures. The best visual indicators for uranium concentration are hematite staining in the pegmatite, followed by the amount of mafic inclusions or crystals. The Bancroft area orebodies are the only known deposits of the general pegmatitic class in Canada that contained economic deposits of uranium. The principal radioactive minerals are uraninite and uranothorite. By comparison with many other pegmatitic occurrences, some of the ore bodies are unusually large, persistent in depth and relatively rich in uranium minerals. At the end of 1981, total ore reserves were estimated at 1,500,00 short tons (1,360, 000 tonnes) averaging 0.11 % U3O8."

Jan 1, 1986

By Tweedy. D. H.

"The paper describes the rapid development of, and operational experience in the utilization of, pneumatic low-pressure pipeline hoisting systems to vertically convey raw coal and rock through shafts, supplementing shaft capacity-the greatest lift to date being 535 m.A typical installation has raised over 250,000 tonnes in less than one year from a depth of 413 m through a 350/ 400-mm pipeline at a rate of 85 tonnes per hour. Operational experience on seven systems has provided valuable data on performance and operating costs.The main advantages of the systems lie in the flexibility of the pipeline to occupy existing free space in shafts and underground roadways, the relatively low first cost, the short delivery and installation time, and the economical running cost.Conclusions are therefore reached on future applications for example, the use of boreholes in older mines where new production technology has outstripped shaft or slope capacity, inter-level hoisting to implement concentration on transport roads and perhaps full mine output from relatively small mines.IntroductionIt is seven years since the basic art and practice of the pneumatic hoisting of minerals was described. The technique was developed in Western Canada by Radmark Engineering and found favour in the United Kingdom with the National Coal Board. Engineering and commercial feasibility trails were conducted in collaboration with the Mining Department and Mining Research and Development Establishment of the N.C.B. There was also considerable involvement with the British Health and Safety Executive.During the last five years, rapid progress has been made in the installation of new systems in the United Kingdom, Hungary and other countries. The operational experience gained makes it possible to report ""in depth"" on these installations, which cover a wide range of different physical mining applications."

Jan 1, 1982

By Jacques Ouellet

Outline What is Microwave energy Investigation of transparency of 40 minerals Melting of Andesite in a MW oven Numerical modeling /Computer Simulations o FEM analysis ?? Some laboratory experiments o Particle Modelling Mw Application to Rock Breakage o A MW Rock Drill Prototype Conclusions What is Microwave energy Microwave energy is an electromagnetic wave consisting two electronic & magnetic wave traveling perpendicular to each other and transporting energy with the speed of light.

May 1, 2008

By G. R. MANSON

The Brisco Barite Mine lies 70 km south-southeast of Golden, British Columbia. Barile mineralization occurs in a northstriking brecciation zone within Ordovician-Silurian Beaver/ oot dolomites and quartzites. Brecciation was caused by faulting related to the Mount Forster-Steamboat Fault. The main barite vein occupies a fault zone and is up to 12 m wide and over 250 m long. It is light grey to white, fine grained and compact; BaSO4 content is 9/. 70 per cent. Production started in 1945 and has continued to the present. Barile originally was removed from an open pit; later, an adit, begun in 1957, reached more than 240 m along the vein, 15 m below the pit floor. Today ore is hoisted from a decline resting some 37 m below the pit floor.

Jan 1, 1984

By John D. Godfrey

Precambrian Shield rocks, exposed in the extreme northeast corner of Alberta, provide the only possibility for a granitic building stone development in the province. Among a wide variety of granitoid rocks in the Shield, the Chipewyan Red Granite is one of the most favourable prospects. Geological mapping and exploration has revealed two prospective sites within a major pluton situated close to navigable water. Cleaned outcrop surfaces show clearly the pattern of joints and lithologic variations within the granite at prospective quarry sites. Other features include: basic dykes, quartz veins, and sheeting fracture zanes. Systematic orthogonally arranged fracture sets and the sheeting zanes are auributed to a tectonic origin. onsystematic irregular fractures are related to surface and nearsurface processes, such as decompression through unloading .

Jan 1, 1984

By T. R. C. Aston, C. M. K. Yuen, J. L. Gilby

"The access tunnels for the Donkin-Morien Mine in Cape Breton, Nova Scotia, comprise two parallel tunnels driven through a sedimentary sequence of sandstone, siltstone and mudstone to intersect the Harbour Coal Seam under the Atlantic Ocean, approximately 3.5 km offshore (Fig. 1). The No. 2 tunnel was driven a total distance of 3579 m using a 7.6 m diameter Loyat full-face tunnel boring machine (TBM) and was supported by steel sets. The No. 3 tunnel was initially driven a distance of 1027 m using drill and blast methods (dimensions 7.6 m wide by 5.3 m high) supported by rock bolts and shotcrete. This tunnel was then completed (front March 1986 to February 1987) using the tunnel boring machine to a distance of 3573 m.During the period May 1983 to December 1984, a major geotechnical research program was undertaken in the Donkin-Morien tunnels by Golder Associates in conjunction w,ith CANMET and the Cape Breton Development Corporation (Yuen et al., 1985). The research program included the monitoring of the performance of the TBM and drill and blast drivages, and the study of the thrusting characteristics and rock-interaction of the TBM excavation. The main emphasis of the research program was on the collection of field data which was to be made available in the form of a comprehensive report for the future use of others who might wish to carry out a detailed interpretation and analysis. The information gained from the program was also used during the tunnel"

Jan 1, 1988

By G. Beckstead, L. Gormely, R. Zimmer, K. Hanneman, B. Nethery

As part of the EIS and permitting activities for the Pogo Mine in Alaska, a risk assessment study for the water management plan was carried out. The basis for the study was a site water volume and contaminant balance model. Probabilistic modeling was carried out using the @Risk Monte Carlo simulation package to investigate the frequency, quantity, and quality of discharges under varying assumptions. The results were used in discussions with regulatory officials as part of the permitting process for the project. The simulation allows probabilistic modeling of key environmental parameters based on input frequency distributions involving both quality and quantity of flow. When combined with predictions of water treatment plant capacities and removal efficiency, this was very useful for defining the likelihood of important regulatory outcomes. Based on the model, certain project modifications were made. Using the simulation as a basis, ongoing dialog with regulators led to consensus that all potential risks have been considered and mitigated for the Pogo Mine according to their likelihood and severity, and that regulatory requirements would be achieved. The paper describes the model and some of the applications for which it was used.

Jan 1, 2005

By W. A. Crosby, W. K. Smith, K. L. McDonald

"IntroductionThis paper describes how the introduction of two blasting techniques and the resuItant development of new dragline digging methods have increased the productivity of single- and double-seam dragline operations at the Rietspruit opencast mine.LocationRietspruit , one of South Africa's largest opencast strip mines, is situated some 11 5 kilometres east of Johannesburg in the Witbank coal field.BusinessRietspruit is a joint venture between Transvaal Consolidate d Land and Exploration Company (T.C.L.) and Shell, South Africa. Rietspruit is administered and managed by Rand Mines, the Mining division of Barlow Rand, transportation and marketing being the responsibility of Shell. The total saleable coal product, approximately 5,5 million tons per annum, is exported via Richards Bay.Presplitting and Throw BlastingPresplitting was initially introduced in September 1980, as a means of dewatering t he overburden and mid burden to facilitate the use of dry-mix explosives a s opposed to slurry explosives.The utilization of the throw blasting technique arose as a direct result of observed ground movement after the successful introduction of presplitting. The first trials commenced in March 1981 on the double-seam operation. The methods, economics and resulting advantages are fully described elsewhere. A brief description follows.Method of PresplittingAfter determining the desired presplit line, 250-mm holes are drilled to top of coal at 4-m to 6-m intervals, dependent on the competency of the rock overlying the coal. A single 60-kg charge of slurry explosives is located at the bottom of each hole, no tamping is used and all the holes are detonated simultaneously. The results are a competent, straight, vertical highwall. This enables accurate control of the first row of blast holes closest to the highwall, which is a prime requisite for successful throw blasting."

Jan 1, 1983

By Robert B. Parsons

"A joint federal/provincial/industry subcommittee of the Intergovernmental Working Group on the Mineral Industry (IOWG) has published an informative and readable report on taxation matters concerning Canada's mining industry. The report, which was presented to the federal and provincial mines ministers in September 1986, identifies and discusses key tax issues relating to this industry. The report is mandatory reading for anybody with an interest in mineral exploration or production in Canada.IntroductionIn 1986, Canada's federal and provincial mines ministers were presented with an important report concerning the taxation of this country's mining industry. This document is important for a number of reasons, two of the reasons being: first, the report contains an objective analysis of the key mineral taxation issues of the day; and, second, the report is the product of a cooperative exercise involving representatives of various facets of the industry and government. The report should be regarded as compulsory reading for anybody who has an interest in fiscal matters affecting mineral exploration and production.The ""Report on Fiscal Proposals"" was prepared by a subcommittee of the Intergovernmental Working Group on the Mineral Industry (IOWO). IOWO is a group of senior federal, provincial, and territorial government officials concerned with the analysis of mineral policy issues in Canada."

Jan 1, 1986

By Pierre O'Dowd

"The southern Abitibi Belt is the major source of gold in Quebec. Although the northern part of the belt is quickly being developed, the area under study will not be downgraded in the near future because it still contains more than 75% of the known reserves in the belt.Gold is found in a variety of geological environments which are part of a small number of distinct structural patterns. For the exploration geologist, outlining such patterns might be easier and more productive than defining, when it is possible, the exact genetic nature of the gold mineralization.Exploring in the right place has always been one of the main concerns of explorationists. This paper briefly describes the various favourable geological settings, and outlines areas, types of structure and lithologies of high potential for gold exploration in the southern Abitibi Belt.IntroductionThe southern part of the Abitibi Belt is a profilic mining area for precious and base metals (Lulin 1990). Although mineralizing processes and controls of polymetallic deposits are well known and understood (Lydon 1984), almost every gold occurrence is a unique case and numerous models have been proposed (Roberts 1987; Hodgson and McGeehan 1982; Hodgson 1990).This study does not define new genetic models for the formation of gold deposits, neither is it meant to elaborate on the existing ones. A genetic approach, is by definition, theoretical and, to some extent, universal. It helps geologists define types of targets and exploration tools but does not outline or quantify target areas. To tentatively summarize the complexity of a genetic approach, a brief discussion on the various genetic models in vogue in Abitibi and the problems related to their use in exploration can be found at the end of this paper."

Jan 1, 1991

By Bruce W. Downing, Philip G. Claridge

"The availability of environmental data is a major concern in the development of an exploration project through the permitting and feasibility stages. The collection of these data should ideally start very early in a major exploration program. Although a large proportion of the environmental data can also be used for exploration purposes, (e.g. stream-sediment, soil, and rock analyses), environmental sampling will rarely have been initiated at an early date. For the Windy Craggy project, a major environmental concern is the potential for generation of acid rock drainage from waste-rock piles. The project is reviewed with respect to the environment of the deposit, deposit geology, mineralization and reserves, the sequence of exploration activities to the present, the potential for the development of acid rock drainage, the geochemistry and water quality, and the integration of exploration and environmental databases and their application to environmental planning. IntroductionIn the classical sense of exploration of a mineral deposit, the efforts throughout exploration are routinely directed at confirming the existence of the deposit and defining its extent, grade and continuity. Environmental issues are usually tackled separately, possibly by different personnel at a later date. When that is the case, an opportunity is lost to build, from an early date , a comprehensive database that (I) will satisfy the needs of conventional exploration and environmental monitoring, and (2) is usable as a predictive tool for environmental impact assessment.The concept of environmental geochemistry is not complex. The availability of environmental data is a major concern in the development of an exploration project to the feasibility and permitting stages. The collection of data should ideally start very early in any major exploration program. In many cases a significant proportion of the geochemical exploration data gathered early in the life of a project will also be used later for environmental purposes (e.g. stream-sediment, water, soil, and rock analyses). Rarely, however, will the data gathered in a geochemical exploration program provide information as complete as that attainable if environmental objectives had been considered in scoping the work.A knowledge both of local and regional geochemical processes can lead to a better understanding of environmental impacts. This understanding is the basis upon which good environmental management practices may be built. Geddes Resources Limited has undertaken a major study of the natural environment in the Windy Craggy area which includes geology, surface and underground waters, soils, stream sediments, glaciers and geomorphology (Geddes Resources Limited, 1990). This paper deals with the building and integration of the exploration and environmental databases."

Jan 1, 1993

By D. J. Reddish

The paper describes a case study where numerical modelling has been applied to predict potential risks associated with inflows of water in active mine workings from an overlying sandstone aquifer. The objective of the modelling was to predict the development of strata fractures and strains as the longwall panels were extracted and investigate their relationship to an sandstone aquifer. The numerical modelling study also included the investigation of the effect of mining on a fault that existed close to the start position of one of the panels. The potential effects of mining on the fault were undertaken by parametric studies adjusting properties for the fault and the relative position of extractions, which allowed the mine planner to position the panel layout accordingly.

May 1, 2003

By W. J. Kuit

"Complex facilities which provide for the collection, management and treatment of effluents emanating from the Sullivan mine and concentrator tailings were made operational in October 1979. Key features of the system are the use of upgraded tailings ponds for the storage of up to 800 million litres of metals-contaminated effluents, a treatment plant employing lime in a high-density sludge process and a sludge-impoundment facility designed for maximum long-term environmental safety. The completed works are capable of satisfying a difficult range of operating requirements imposed by highly variable weather conditions, drainage flows and soluble metals loadings. Final capital expenditures for the project approached $10 million and annual operating costs are about $0.8 million.This paper discusses the Kimberley effluents treatment project and the major considerations in its development. The treatment process, major plant equipment and initial operating experience are also described.IntroductionCominco Ltd. has worked the Sullivan orebody at Kimberley, B.C. since 1909 and has operated a concentrator some 5 km distant from the mine since 1923. Over the last 70 years, in excess of 120million tonnes of ore have been mined, and production continues at an average rate of 6,500 tonnes per day. It is a well-known fact that the contribution of this operation to Canada's mining industry and, in particular, Cominco's development has been significant. However, this success has not been without some undesirable side effects.Unfortunately, the Sullivan is one of only a few major Western Canadian orebodies which may be classed as ""acidic"" in nature. That is, the primary economic minerals, galena and marrnatite, are enclosed in a siliceous host rock with abundant pyrrhotite, but with little or no accompanying alkaline gangue minerals such as calcite and dolomite. The unavoidable consequence of mining such an ore is that contact with air and water generates an acid mine drainage containing various soluble metals orginally present as minerals.This problem also arises in the concentrator's tailings ponds, which, in the case of the Sullivan, are two separate impoundments of different materials. The 1,100 tonnesl day of ""iron"" tailings are primarily pyrrhotite which is surplus to the requirements of a separate operation that produces sulphuric acid as an intermediate to phosphate fertilizers. Inert gangue minerals with only a minor sulphide content are the main constituents of the 1,200 tonnes/ day of siliceous tailings. Corresponding to the relative proportion of sulphides in the solids, the decant from the iron tailings is substantially more contaminated than that from the siliceous pond."

Jan 1, 1980

By K. Ghyselbrecht, R. Swennen, Y. W. Chiang, V. Cappuyns, R. M. Santos, T. Van Gerven, B. Meesschaert

Heavy metal contamination from mining and metallurgical activities of aquatic systems poses significant risk to the environment and human populations. The investigation of the distribution and immobilization mechanisms of heavy metals in sediments and soils has recently attained high priority. Different remediation methods can be employed to suppress or eliminate these contaminants. A tailored approach using both commercially available and in-house made adsorbents to rem ediate a heavy metal contamination site due to historical metallurgical activities in north Belgium is studied in this paper.

Jan 1, 2011