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By G. A. Maki, P. J. Fullman, R. G. Roden

"In October 1984, Rocanville Division began using a stacking system to handle potash mill tailings. Previous to this date, mill tailings were slurried to the top of the tailings pile and allowed to debrine while flowing down the pile. With the new stacking system, slurried tailings are fed to mobile stackers. The stackers consist of cyclone packs to debrine the tailings and drag conveyors with screw discharges to deposit the tailings onto the existing pile. This paper deals with the various aspects of the project from conception to its present state.IntroductionPrevious to 1984, when the stacking project was first implemented, potash mill tailings were handled as follows. Mill tailings were first debrined to approximately 65010 solids using a cyclone cluster. The cyclone underflows were then introduced onto a vacuum scroll filter table. Here the tailings were further debrined and discharged into the disposal tank where the tailings were reslurried with reclaim brine and pumped to the tailings disposal site. At the disposal site the slurry was discharged onto the tailings pile and by a natural settling process the tailings were debrined with the brine ultimately collected in the reclaim brine ponds. The shape and profile of the tailings pile was controlled by building salt dykes to control the flow of the discharged tailings slurry. As the tailings pile grew in height, booster pumps were added to the disposal system."

Jan 1, 1990

By William H. White

"AbstractThe value of anomalous metal contents of trees as an aid to the discovery of mineral deposits was tested under field conditions cm four known ore deposits. Results indicate that a base-metal deposit, or any deposit containing zinc or copper, casts a 'metal shadow' into the overlying soil which remains approximately positioned above the deposit, regardless of the type of overburden or the movement of groundwater.The unusually high content of zinc or copper in trees growing within the limits of this 'metal shadow' constitutes an anomaly which can be detected and ,plotted in the field The field kit and certain points of the field technique are described briefly; and the characteristics of plant anomalies and possible limitations of their use are mentioned.IntroductionRecent investigations concerning the metal content of trees indicate not only wide variations in the metal content of different species and in different parts of the same tree but, in addition, suggest that the metal content of a tree is related to that of the subjacent bed-rock. Abnormal values found by Warren, Delavault, and others in trees growing above or near orebodies suggest a new tool which may prove of considerable value in exploration work. Evaluation of this new tool must involve consideration of the following questions:(I) Is the technique one which can be used under field conditions by persons not specially trained; and can results be duplicated within reasonable limits of error? Rather than taking tree samples for subsequent laboratory analysis, it is highly desirable that analyses be made on the spot. This allows anomalous results to be checked and additional samples may be taken at key points."

Jan 1, 1950

By Robert B. Parsons

"The Province of Manitoba tabled a Budget on March 11, 1992, which contains some important new initiatives designed to improve the fiscal environment for mining in the province. In addition, the Minister of Energy and Mines has released details of the Mineral Exploration Incentive Program which was originally announced in the 1991 Budget.Introduction""We recognize the important contribution o f mining to the economic activity of our province, including direct and service jobs and export earnings. We are determined to secure its future."" - The Honourable Clayton Manness, Minister of Finance, Province of Manitoba, March 11, 1992.With these words of introduction, Manitoba Finance Minister Clayton Manness announced a number of significant measures aimed at improving the fiscal regime for exploration and mining in Manitoba. At the same time, details of the Manitoba Mineral Exploration Incentive Program (MEIP) were released."

Jan 1, 1992

By D. McConchie

The use of Bauxsol? (physically and chemically modified alumina refinery residues) to treat acid rock drainage (ARD), and sulphidic waste rock and tailings, provides new options for managing some intractable environmental problems at both derelict and active mine sites. Treatment of ARD waters using the Bauxsol technology shows that the effectiveness of raw Bauxsol material can be enhanced by including modest amounts of selected industrial minerals or common chemical additives. The type and amount of additive required and the amount of the blend needed to treat the water depends on the initial composition of the water and the target water quality; for some ARD waters, optimum treatment may require one or more changes in the type or amount of additive used. Maximum treatment efficiency can be achieved only when a balance is maintained between the rate of trace metal binding and the rate of change in water pH; adding treatment reagents faster than can be accommodated by the reaction kinetics will not result in more rapid water treatment. This paper presents the results for treating several ARD waters to illustrate the importance of blend selection and treatment procedure. Although treating ARD water is often necessary, this strategy treats the symptoms rather than the cause. The best permanent solution is to treat the sulphidic waste rock or tailings such that they do not continue to oxidise and produce acidic metal-rich leachates; sulphide oxidation needs to be stopped or slowed to a rate that can be accommodated by normal environmental processes. Capping lined impoundments is not a solution because all caps and linings will inevitably fail some time in the future creating a nasty surprise for some future generation. Adding lime is also less than ideal because the lime leaches from the treated material; treatment often appears to be effective for a few years and then fails. Bauxsol technology offers effective alternatives to conventional liming and capping procedures and Bauxsol blend application rates and procedures can be planned to ensure that no acidic or metal-rich water can ever escape from the site. Bauxsol can be physically mixed with the sulphidic mine wastes or it can used to form subsurface permeable reactive barriers, or both. Bauxsol treated waste rock and tailings can be immediately and effectively revegetated. In this paper we present leachate quality and plant growth rate data for several sulphidic waste rock and tailings deposits treated using the new technology.

May 1, 2003

By Yuhua Wang, Wei Sun, Dongfang Lu, Yuehua Hu, Tao Jiang

"With the continuous depletion of high-grade tungsten ores, the low-grade refractory wolframite has become an important source for the tungsten industry. However, the large-scale utilization of low-grade refractory wolframite is disappointedly scarce, it is due to leanness of valuable minerals, complex mineral characterization and use of toxic collectors.The aim of this study was to develop an environment-friendly processing flowsheet, which was used for beneficiation of low-grade tungsten ore containing 0.45% WO3 from New Brunswick in Canada, and the content of arsenic is 0.68% in this materials. The objective of beneficiation studied was to obtain a concentration containing 60% WO3 with less than 0.5% of arsenic under the condition without any flotation reagents. In this environment-friendly processing flowsheet, magnetic separation technology, classification and gravity separation technology were combined and employed. Firstly, magnetic separation was employed for the first pre-concentration process, over 95% of the feed was rejected as the final tailings, meanwhile, over 85% of arsenic minerals were removed with tailings. Secondly, gravity separation tests were employed on the classified magnetic pre-concentrate in the second pre-concentration process, a second pre-concentrate with WO3 grade of 54.32% and As grade of 5.41% was obtained. Finally, two stage magnetic cleaning were conducted on the second pre-concentrate for upgrading the second pre-concentrate, the mostly arsenic and gangues were removed from the second pre-concentrate. Finally, this novel processing achieved an effective recovery of fine wolframite from low grade tungsten ore with high arsenic. A concentrate with WO3 grade of 64.81% were obtained in new opened processing flowsheet, and As grade was less than of 0.5% in this concentrate. Furthermore, remarkable feature of this processing flowsheet is environment-friendly due to avoid using the toxic flotation reagents during the whole mineral processing.INTRODUCTIONTungsten is an essential metal and is the most widely used in industrial production such as national defense, electro-mechanical products, textile and leather sectors (Srivastava et al., 2000). Wolframite and scheelite are the main mineral sources of tungsten metal. With the continuous depletion of high-grade tungsten ores and the increasing demand for tungsten alloy, the low-grade refractory wolframite has become an important source for the tungsten industry. However, the large-scale utilization of low-grade refractory wolframite is disappointedly scarce, it is due to leanness of valuable minerals, complex mineral characterization and heavy use of toxic collectors."

Jan 1, 2016

By Andrew D. Lapworth

The use of geological and grade models has been standard practice in mine design for many years now, with a wide range of software available to create and analyze the models. Although geotechnical parameters are also of vital importance for mine planning, there has been very little in the way of commercially available systems for integrating geotechnical data into the mine planning and design process. Sirovision is a new technology based on digital photography for automated, safe and accurate 3D mapping of geological and geotechnical features in rock faces. Datamine has integrated this capability into its product range so that Sirovision becomes an integral part of day-to-day face mapping, mine geology and geological / geotechnical modeling in both open pit and underground mines. This results in improved fragmentation for loading, hauling and processing, and for open pits local geotechnical conditions can be taken into account to improve slope design and control. This paper describes some of the ways that geotechnical modeling can be used to create more refined and cost effective mine designs and then discusses the role of Sirovision in enabling the raw data required for such modeling to be collected quickly, safely and reliably.

May 1, 2007

By P. Dauphin

"CANMET’s Mining and Mineral Sciences Laboratories have developed the Canadian Mining Technology Network (CMT-Net), a website to provide industry with up to date information on technologies in several areas. This paper gives background on the Mineral and Metal Processing sector, describes the steps leading to the development of the websites strategy and gives a tour of CMT-Net. IntroductionThe government of Canada is developing a strategy aimed at fostering the development of value-added activities in the area of mineral and metal processing (MMP). Natural Resources Canada (NRCan) and Industry Canada will partner in delivering on this strategy. Instrumental in defining the main thrusts of the value-added strategy was a series of consultations held across Canada with representatives of companies and organizations active in the sector. The objective of the consultations was to identify barriers to the development of activities which add value in the sector, as well as point to positive factors.Following the consultations, a discussion paper was produced, “From Mineral Resources to Manufactured Products: Towards a Value- Added Mineral and Metal Strategy for Canada” (Natural Resources Canada, 1998). The paper reviews the sector’s structure and main statistical information, lists some of the positive factors and barriers to value-added activities and defines a new partnership between industry and government that will lead to more valueadded activities. The main objective of the paper is to serve as a discussion document between stakeholders during the development of the strategy."

Jan 1, 1999

By James F. A. Hatley

Northern Saskatchewan comprises an area of about 350 000 km2 and boasts some of the world's largest known high-grade uranium deposits. The successful mining of these deposits, however, can not be accomplished without overcoming technical challenges. Not only is the high grade of the uranium ore challenging, but mining methods need to be developed to deal with groundwater at very high pressures, and ground conditions that vary substantially from excellent to wholly unconsolidated clays and sand. This paper discusses the various mechanisms of inflows at the three of the Cameco Corporation Mines in Northern Saskatchewan. The risk of inflows is quantified in terms of unique challenges from hydrogeologic conditions, rockmass integrity, and uncertainty in geologic conditions. Mitigation strategies in case of an inflow are also briefly described. The paper concludes by addressing the impact of institutional rules (corporate standards) on minimizing, monitoring, and controlling the probability and/or impact of unexpected inflows.

Aug 1, 2010

By Stephen Hardcastle

Personnel Heat Exposure Issues In Canada?s Deep Mechanized Mines ?Project developed in 2004 ?Base/precious metal industry identified heat stress/management as a major challenge affecting productivity and operating costs ?Project started in 2005 ?Current research nearing completion ?Guidelines, further data analysis and ?Communicating the Science? will continue into 2011 Managing Heat Exposure Control?. The cost implications ?Controlling the environment ?Ventilation already a major expenses/energy user ?Large Canadian mines are currently delivering massive volumes of air 15-20 tons of air/ton ore ?Large investments in ventilation upgrades, mechanical cooling

May 1, 2010

By Robert J. McCarthy

Mining has a record of achievement in developing and adopting new technology to facilitate the extraction of increasingly challenging resources. Certainly larger, or more capable, mining equipment has allowed mining companies to mine mineral deposits at lower unit costs; however, there has also been the advent of computerized systems that aid in the management and tracking of mining operations. Unfortunately, the latter computerized systems have not always had the success anticipated with their implementation. This paper explores the view that increased transparency of the planning and operating cycle in a mine, as provided by certain computerized systems, can result in some resistance from those whose work becomes ?exposed?. Examples are drawn from industry-leading technologies for both mine management and reconciliation that illustrate the issues and challenges that result. The adoption of appropriate change management principles is suggested as a best practice in planning and mitigating the challenges in implementing technologies which increase transparency in the mining environment.

May 1, 2011

By Paivi Suikkanen, Kari Hietala, Kaarlo Haavanlammi

"Processing of high-magnesia concentrates, the recoveries of nickel and copper, as well as those of platinum group metals (PGM’s) and cobalt are key issues of the Nickel Smelting technologies. PGMs are typically found in association with each other, but also importantly with nickel and copper. A challenge of producing saleable concentrates at acceptable recovery degrees, an increasing focus on the sustainable use of metals and recent decreases in the value of nickel has increased the interest to find a reliable route from Cu-Ni-PGM bulk concentrates to product. According to studies, most efficient process for Ni-Cu-PGM concentrates is flash smelting using DON process20 years ago, in 1995, Outokumpu commenced at Harjavalta a new Nickel Flash Smelting technology based on the Direct Outotec Nickel (DON) Smelting Process. The DON process enables production of high-grade nickel matte with low Fe-content directly in the Flash Smelting Furnace (FSF) without subsequent converting. Metal values from the smelting slag are recovered in the Electric Furnace (EF) as iron containing Ni-matte. Matte refining is based on atmospheric pre-leaching and total pressure leaching. Nickel, cobalt and iron are leached leaving a leach residue containing small amount of gangue minerals and PGM’s. Iron is removed from the leach solution in and nickel will be recovered with standard methods. Overall > 95% metal recovery can be expected with low energy consumption and low environmental impact."

Jan 1, 2014

By Shigeru Sarata

A wheel loader is one of the main loading machines in open pit mines. The authors have been conducting research and development on autonomous operation of loading by a wheel loader. The most common loading method by a wheel loader is the ?V shape? path method. The loading operation consists of cycles of scooping from the pile, traveling to the dump truck, loading on the dump truck and return traveling to the scooping point for the next cycle. The traveling path includes a switchback in the middle of the path. The moving direction of the loader is changed at the switchback point. From observation of V shape path loading operations by experienced human operators, it seems that they control the bucket position between the scooping point and loading point on a shorter path for higher productivity. A new path planning method is proposed this paper, whereby a point on the center of the tip of the bucket is controlled moving from the initial point and the final point. The motion of the controlled point is generated by the wheel steering the wheel loader. The controlled point is moved along the direction to the final point; however, the motion and mechanism of wheel loader have restrictions, such as the velocity of the loader, the steering angle, and the steering angular velocity. Because of these restrictions, the path of the controlled point is not a straight line between the initial and final points. When this control method is applied between the scooping and the dumping points directly, the planned path is not stable in the leaving wing of V shape path. Therefore, the initial position of the wheel loader is set at the switchback point, then two approach wings to the scooping and the dumping points are made. The whole planned path is obtained by connecting the two paths. The shape of the planned path is strongly affected by the position of the switchback point, as well as the scooping and the dumping points. By simulation of path planning at different switchback points with the combination of the scooping and the dumping points, the paths for more effective loading are determined. The results of the simulation are presented in the paper.

Aug 1, 2013

By T. L. Tanton

"The New Helen mine is 12 miles east of Michipicoten harbour on lake Superior. It is 2 miles east of Wawa station, on the Algoma Central railway, with which it is connected by a spur line railway and a highway.The mine was discovered by Ben Boyer in 1898 during the gold rush near Wawa lake, Ontario. The original discovery was of solid hematite ore extending to a height of 100 feet on a hill rising abruptly on the east side of Boyer lake. The property was acquired by the Algoma Steel Corporation and mining was commenced in 1899. The first iron ore was shipped in 1900. The mine was operated until 1918 when the hematite became exhausted at a depth of 800 feet below Boyer Lake level.Drilling at the Helen mine, after 1910, revealed a large body of siderite both below and to the east of the hematite. By 1913, the body was known to be about 200 feet wide, 3,000 feet long, and at least 2,200 feet deep. In this there was estimated to be 100,000,000 tons of proved and probable siderite ore. An adit was driven into this body in 1917, and in 1918 work was suspended. In 1937 the Algoma Steel Corporation proceeded with the development of the New Helen mine by open-cut mining, and the beneficiation of the ore by sintering. Production commenced in 1939 and has since been maintained at the rate of approximately 500,000 tons a year.From 1900 to 1918, inclusive, the total production from the Helen mine was 2,823,369 tons of hematite ore and 51,930 tons of pyrite. From 1939 to the end of 1945 the total production from the New Helen mine was 3,921,455 gross tons of siderite ore.GEOLOGYThe Helen property is underlain by rocks of Precambrian age. For general description, and a statement on the structure of the iron deposits, the map-units are those shown in Fig. 1.The oldest rocks occur in a complex that lies north and south of an east-west trending zone, 1 ½ miles long and ¼ mile wide, in which the iron deposits occur. That part of the complex lying south of the iron deposits includes small masses of altered conglomerate and slate, and greenstones and pyroclastics. Other fairly abundant rocks are sericitic, chloritic, ottrelitic, and carbonatized schists of doubtful origin, and almost massive metamorphic rocks in which a development of carbonate, ottrelite, quartz, and other minerals has obscured a pre-existing schistose structure. Felsite and quartz porphyry are· prominently exposed south of the iron deposits."

Jan 1, 1954

By Friedrich Benthaus

"The natural and man-made realities on either side of the Atlantic are different. Therefore, a large part of the other side' s knowledge and experience cannot be transferred easily. In the following, the author will attempt to describe some of those developments in the German hard coal industry which may be of particular interest to readers on this side of the Atlantic.The area of the Federal Republic is quite small, especially if compared with a country as large as Canada. On a territory the size of the maritime provinces of New Brunswick and Nova Scotia, Germany holds coal reserves roughly corresponding to the total Canadian reserves. More than 20 billion tons of hard coal down to a depth of 1500 m, and more than 30 billion ton s of brown coal of lignite are technically and economically extractable acording to current technology.However, not only are Germany's coal resources more concentrated; the country is also densely populated, and there are dense networks of railroads and highways All components of the so-called infra-structure are available everywhere, be it electricity, any machinery or personnel. Public opinion is likely in favour of an increased utilization of coal.The coal industry is well developed through a long evolution covering centuries. As a consequence, there is an effective and intensive cooperation of numerous bodies and institutions concerned with coal mining, from government agencies including the inspectorate to suppliers, trade union s, producing companies, to jointly operated management and research organizations. In the Federal Republic, hard coal is mined in deep mines only, and lignite in general, only from open-cast pits. There is a complete organizational and geographic separation of hard and brown coal in Germany. Because the Federal Republic holds only insignificant mineral oil and very little natural gas deposits, coal is essentially the only and consequently the most valuable source of energy."

Jan 1, 1984

By T. G. Sitharam, Resmi Sebastian

"Wave propagation studies across jointed rocks have significance in the fields of rock mechanics and geophysics. The passage of a seismic wave induces strains in rocks and often, these strains are of low magnitudes except at the vicinity of source. These low magnitude strains are generally in the elastic range and hence elastic constants necessary for the design and analysis of strength of rock mass, can be derived from wave velocities. Measurement of travel time velocities and measurement of resonance frequencies are the two methods usually adopted for obtaining wave propagation velocities.Resonant column apparatus measures wave velocities from the resonant frequencies obtained during testing. Depending on the type vibration applied, torsional or flexural, shear and compression wave velocities are secured. By varying the amplitude of vibrations applied, various strain levels can be introduced and corresponding resonant frequencies and wave velocities can be calculated. The resonant column experiments were performed on a model material, hardened Plaster of Paris (POP) samples, in laboratory. The paper explains the preparation of samples and the working mechanism of resonant column apparatus along with the estimation of wave velocity from resonant frequency. The numerical simulation of resonant column apparatus using distinct element method and its validation with the experimental results are presented in the paper.A distinct element code is usually used to simulate the movement of materials with intersecting discontinuities. Finite rotations and displacements of individual blocks representing the material are permitted and new contacts between the blocks are identified as the calculation progresses. Three dimensional Distinct Element Code (3DEC), the software intended for the numerical simulation of rock engineering projects, can well simulate the behavior of jointed rocks under static and dynamic loading conditions. The numerical simulation of resonant column apparatus has been performed with 3DEC considering its efficiency in modeling jointed rocks.The numerical modeling of the resonant column apparatus with application of torsional and flexural vibrations to the sample is elaborated in the paper. The response of samples to a range of frequencies is obtained and the frequency that induces maximum displacement in the sample is measured as the resonant frequency, for any particular strain level. The displacements measured at various points of the sample during application of vibrations are compared and presented. The numerical modeling of resonant column apparatus with an intact sample (without joint) and a sample with a joint incorporated are explained at a particular strain level. The resonant frequencies obtained from laboratory experiments and numerical simulations are compared and illustrated. It has been found that resonant frequencies obtained using numerical and laboratory experiments are in good comparison and can be extended for various strain levels and sample conditions."

Jan 1, 2015

By Michel Gauthier, Jacque Trottier

"ForewordA symposium on base metal deposits was held in Bathurst, New Brunswick, from June 10-13, 1990, sponsored jointly by the Geological Surveys Branch of the New Brunswick Department of Natural Resources and Energy, the New Brunswick Prospectors and Developers Association, and the Geology Division of the Canadian Institute of Mining, Metallurgy and Petroleum. Papers prepared for the symposuim are being published as a series of articles in the CIM Bulletin. This third paper (the first was by Fyffe, et al., in Vol. 83, No. 938, the second is in this issue) in the series presents an overview of the tectonic setting and geochemistry of base metal deposits in the Eastern Townships of Quebec.ABSTRACTIt is well known that the classification system of volcanogenic massive sulphides (VMS) is based upon their metal content. This metal content, the result of hydrothermal solutions circulating within strata underlying the deposits, is generally thought to be related directly to two parameters: (1) the nature of the underlying stratigraphic sequence; and (2) the physico-chemical conditions that existed at the time of the hydrothermal event. Furthermore, these two parameters are, in turn, related to the tectonic setting. One must bear in mind that these parameters are diachronous and evolve with time. These factors are considered in our analysis of the major VMS deposits of the southeastern Quebec Appalachians. This analysis will describe the time and environment of formation of these deposits and integrate them into an evolving paleotectonic model.VMS deposits in the southeastern Quebec Appalachians formed during three distinct metallogenic episodes. During the first episode, which involved early closing of the Iapetus Ocean and associated destruction of oceanic crust by subduction processes(Early Ordovician?), cupriferous VMS deposits hosted by pillowed, mafic (boninitic) lava flows were formed in immature island-arc systems (""Cyprus-type"", e.g. Huntingdon deposit).In the second episode, which also occurred during the closure of Iapetus but at a later stage (Early to Middle Ordovician), mature island-arcs formed and hosted polymetallic VMS deposits (""Kuroko-type"", e.g. Eustis deposit).Finally, during culmination of the Taconic and/or Acadian orogenies (Middle Ordovician and/or Devonian), transtensional basins, associated with tholeitic to transitional mafic volcanism began to develop. Major sedimentation occurred contemporaneous with volcanism, and within this framework polymetallic VMS deposits were formed (""Besshi-type"", e.g. the Memphremagog deposit).Although incomplete, the proposed paleotectonic model represents the sequence of the tectonic settings that prevailed during the formation of the VMS deposits of the southeastern Quebec Appalachians."

Jan 1, 1991

By Halet. R. A.

"The Quesabe Mine, owned by Brunston Mines Limited, is a gold deposit in the south central part of Duprat Township, northwestern Quebec, about 10 miles northwest of Noranda.It is one of the few gold mines in Canada developed since World War II. The occurrence of gold in the Quesabe fault structure has been known for many years, but serious exploration did not begin until 1945. By 1949, 15,000 feet of diamond drilling had been completed and a shaft sunk to a depth of 635 feet, with lateral development on the 450 and 600 foot levels. In 1949 and 1950 a new shaft was sunk to 1,050 feet, new levels were established at 800 and 1,000 feet, and ore was mined and shipped to the Noranda smelter. After November 1950 the ore mined was treated in the company's own mill. The grade of ore was marginal under existing economic conditions, and production was suspended in April 1952. The mine produced about 100,000 tons of ore with an average grade of approximately 0.25 ounces of gold per ton.GeologyThe bedrock formations are all Precambrian, and the general geology of the area has been described by W. G. Robinson (1). The rocks in the vicinity of the mine are acidic and basic volcanics of the Keewatin series (andesite, rhyolite, agglomerates, tuffs) invaded by the Flavrian Lake granite stock, and by dykes and irregular masses of intrusive felsite, quartz porphyry, syenite-porphyry, diorite, and lamprophyre.The mine workings are in andesite and felsite, about 2,500 feet west of the western margin of the Flavrian Lake stock.The principal structural feature of the area, from an economic point of view, is the Quesabe fault. This steeply-dipping fault cuts all the rock formations of the area, and has been traced for about 11 miles along a strike of north 65 degrees east from Lake Arnoux in the northeast corner of Dasserat Township to Duprat Lake near the east boundary of Duprat Township."

Jan 1, 1949

By Franco Oboni

Numerous voices are raising around the world to show how misleading and fuzzy commonly used risk assessments methods are. These criticisms come at a time when public trust in ?proponents of new projects?, operators, private or governmental, seems to have hit a low and the legal system ?targets? public officers. It is common that technical experts and the public strongly disagree in their analysis of risks. Risk definition requires the evaluation of probability and consequences and those words are oftentimes enough to stir great worry to the public. Thus it is nowadays commonly understood that ?reality? is not scientific, but resides in public opinion, hence urging technical people to communicate better, more transparently. Blatant failures on both counts have lead to the emergence of ?new myths? used to justify complacency using ?complexity? and other buzz words as an alibi. This paper (together with its companion presented elsewhere) explores how poor ?common practices? in Risk Assessment contribute to biasing project team, design teams opinions, skew decision-making process and finally misrepresent reality to the public resulting precisely in the raise of public distrust, legal implication witnessed around the world. The discussion first reviews the pitfalls of common approaches (FMEA, Probability Impact Graphs) pinpointing them as possible causes of future legal liabilities. An alarming disconnect also comes from various codes, ISO 31000 itself has this flaw, invoking the term ?acceptable?/?tolerable? without defining it or giving any guidance for its determination. Wide-spectrum public consultation could be developed to define a ?modern? social acceptability criteria helping all the stakeholders making/understanding decisions. Another alarming disconnect comes from the poor definition of consequences of mishaps and their societal ripple effects. This aspect is indeed mostly ignored in codes, leaving ample room to biases and censoring applied to potential losses. In our society no one seems to have anymore the possibility of hiding behind a shroud of ?carefully maintained? misrepresentation. It is time to act and ?write the book? for proper risk assessments avoiding misrepresentations.

May 1, 2013

By I. Stanoev, V. S. Stoilov, I. Gradinarov, E. D. Visariev, I. A. Bonchev, Aurubis Bulgaria

"Aurubis is the leading integrated copper group and the world’s largest copper recycler. In Copper smelter Aurubis Bulgaria (Pirdop), the residual copper in the slags from Flash furnace and Converters is recovered by flotation. The slag processing comprises: pit cooling, crushing, two stages grinding (autogenous and ball) and flotation. The copper concentrate is thickened and then is filtrated by vacuum disk filter. The thickener overflow is sent to settler for additional clarification. A resent throughput increase resulted in higher solid content in the thickener overflow due to insufficient thickener area. Different scenarios to overcome the issue were evaluated (new thickener, reagents and reconstruction). An increase of the thickening area by installation of lamella modules was chosen as the most promising option. Three lamella modules (1 m3 each) were installed in conventional thickener for the test. Number of sampling campaigns was done to evaluate the effect on solid content in overflow. Parameters of the dewatering cycle were collected during sampling campaign. The products grain size distribution was defined - thickener feed, thickener overflow with and without lamella. The thickener overflow with lamella modules has 2.12 g/L less solid content. The decrease was 71.8%. According to the tests results, the whole conventional thickener was reconstructed with lamella modules. The thickener area was increased by more than 400 m2.INTRODUCTIONIn Copper smelter Aurubis Bulgaria, the copper in slag from the Flash furnace and the Converters is recovered by flotation. The scheme of slag processing is crushing, two stage grinding (autogenous and ball) and flotation. Till 2010 the grinding cycle in the plant was in two stages: the first stage was AG Mill 70×23 working with a classifier and the second stage was ball mill 3.6/5.5 working with a hydrocyclone. In 2010 a new AG Mill 65×78 with hydrocyclone was put in operation in order to increase throughput of the plant. The second stage of the grinding cycle was not changed."

Jan 1, 2016

By Robert B. Parsons

"The Canadian Exploration Incentive Program (CEIP), which was announced by the federal government on May 3, 1988, promises to maintain the viability of flow-through shares as a financing mechanism which has proven to be so crucial to the health of the junior exploration sector. This month, Tax Notes examines, the main features of CEIP, which will come into play on January J, 1989. IntroductionOn May 3,1988, the Honourable Marcel Masse, Minister of Energy Mines & Resources, and the Honourable Gerald Merrithew, Minister of State (Forestry and Mines) announced the Canadian Exploration Incentive Program (CEIP). Under CEIP, the federal government will make cash payments to eligible applicants equal to 30% of eligible exploration expenses. CEIP payments will be available with respect to both mineral, and oil and gas, exploration. In essence, the program will replace the ""mining exploration depletion allowance"" (MEDA) presently applicable to mineral exploration, and the Canadian Exploration and Development Incentive Program (CEDIP) which is presently available to the oil and gas exploration sector.This paper discusses briefly the main features of CEIP insofar as the program will affect mineral exploration. The comments herein are based on the Canadian Exploration Incentive Program Act which received Royal Assent on July 21, 1988, and on a discussion paper which was released by EM&R in May 1988. The bulk of the rules relating to the program will be in the form of regulations which have yet to be finalized. It is understood that EM&R would like to have the regulations in force by October I, 1988, when the oil and gas portion of CEIP becomes effective. (The rules relating to mineral exploration will become effective January I, 1989)."

Jan 1, 1988