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By Michael J. Beus

The National Institute of Occupational Safety and Health-Spokane Research Laboratory (NIOSH-SRL) have developed a Shaft Conveyance Monitoring System (SCMS). Assessment of current hoisting technology has shown that monitoring wire rope tension and conveyance position and load directly from the skip or cage top offers several significant safety, production, and maintenance advantages. The SCMS consists of conveyance position and guide displacement sensors, a battery power supply and charging system, and a new sensor to measure hoist rope tension. This device provides a warning of the occurrence of ?slack rope? a particularly dangerous condition. A 2.4 GHz radio link transmits data to the hoistroom. A reduced scale hoisting test facility has been constructed to test these components prior to field trials. The advantages of monitoring wire rope tension and conveyance position and load directly from a skip or cage top will be discussed. Field tests are underway in full-size shafts to refine the concept and evaluate long-term reliability and maintenance requirements. Application of this technology may result in decreased maintenance costs as well as safer, more productive hoisting operations.

May 1, 2001

By M. B. Kime

"Discrete-element method (DEM) modelling is a powerful tool for studying particulate systems within the mineral processing industry. DEM simulations were conducted to investigate the power draw, load behaviour, and impact energy profile of an experimental ball mill under different milling conditions. The variables considered were mill rotational speed (percent critical speed), ball size, and lifter face angle. The simulation results indicated that the grinding efficiency would be enhanced by using 80% critical speed, 30 mm ball diameter, and 45° lifter face angle. These findings can be useful in guiding actual ball milling tests involving an ore sample.RÉSUMÉ La modélisation par méthode des éléments distincts (MED) est un outil puissant qui permet d’étudier les systèmes particulaires au sein de l’industrie de traitement des minerais. Des simulations par MED ont été menées de façon à étudier le profil de la consommation énergétique, du comportement de la charge et de l’énergie de rupture d’un broyeur à boulets expérimental dans diverses conditions de broyage. Parmi les variables prises en compte figuraient la vitesse de rotation du broyeur (vitesse critique en pourcentage), la taille des boulets et l’angle de coupe de la cornière élévatrice. D’après les résultats de la simulation, on pourrait améliorer l’efficacité de broyage en utilisant une vitesse critique de 80 %, un diamètre de boulet de 30 mm et un angle de coupe de 45 ° de la cornière élévatrice. Ces résultats peuvent se révéler utiles pour les essais concrets de broyage à boulets impliquant un échantillon de minerai.INTRODUCTIONComminution is a very energy intensive process. It consumes approximately 5% of the electricity produced worldwide and more than 50% of the total energy used in mineral processing plants (Pokrajcic, 2010). Among all the comminution stages, ball milling is one of the most energy intensive processes. In ball mills, rotational movement provides the rise of the load and the media that are projected and impact on the mill shell at lower angular displacement, resulting in particle breakage. Ball mills are able to reduce particle size over a relatively wide range of particle sizes. This explains their wide applicability in research laboratories and the mineral processing industry."

Jan 1, 2017

By E. Onal, C. Craddock, A. Chapman, M. R. Endsley

ABSTRACT Mining equipment operators must interpret and respond to complex information delivered by technology-centric rather than user-centric systems. The ability to achieve high situation awareness (SA) in the face of this data overload is a key challenge to effective decision-making and information exploitation. Incidents attributed to human error that compromise safety and result in loss of revenue, or even life, are often the result of system designs that overload human cognitive capabilities. This paper defines SA as it relates to the operation of mining equipment and describes the design and preliminary evaluation of a new electric shovel operator user interfa

Jan 1, 2013

By J. K. Atherton

If the metals sector is to contribute successfully to sustainable consumption we must adopt principles and practices which address the entire life cycle of the materials we produce. Progress must be founded on a sense of shared responsibility for the resources we utilize and the materials we create - it is this integrated approach which lies at the heart of materials stewardship. Materials stewardship means mining and metals companies producing materials in a responsible manner and then working with others, beyond their site, to ensure that the downstream material flows and applications are managed properly to create maximum societal value. In September 2006 ICMM published 'Maximizing Value: Guidance on implementing materials stewardship in the minerals and metals value chain'. This document takes a practical view presenting structured guidance as well as good practice case studies. In the publication, materials stewardship is described in terms of the range of activities that can be undertaken to ensure that all parties work collectively toward the responsible use of metal and mineral resources. This paper introduces the materials stewardship concept as set out in `Maximizing Value' and describes the business case for implementation as well as the ICMM framework for promoting materials stewardship.

Jan 1, 2007

By A. R. Barnes, N. Stubina

Increasingly, gold producers are forced to treat ever more refractory ores. While ores containing pyrite, arsenopyrite and carbonaceous material have been subjected to complete pressure oxidation (PDX) as the standard process for such ores, recent improvements in fluid bed roasting technologies have led to a resurgence of interest in roasting as a viable alternative. The lower capital and operating costs of roaster installations add further impetus to this trend. The Extractive Metallurgy Group at Xstrata Process Support operates four fluid bed reactors of various sizes which have been utilised on a large number of projects to treat highly refractory ores. Preliminary mineralogical modelling of both the physical and chemical aspects of the roasting process and subsequent testing under carefully controlled conditions has allowed clients to obtain gold recoveries approaching or matching those achievable by PDX. The flexibility of the units to operate in various modes- " bubbling bed", circulating bed, two stage, sub-stoichiometric and combinations of these, and the range of sample sizes accommodated, from a few kilograms to a few tons, has enabled XPS to accommodate clients with a wide variety of gold bearing refractory ores from all over the world. This paper outlines the key challenges of fluid bed roasting of refractory gold ores, describes the methodology used to design the testwork program and provides some results from select test campaigns.

Jan 1, 2011

By Ashley Tews

In 2005, we automated a forklift-based Hot Metal Carrier to be capable of typical metal transfer operations around a smelter. The project was highly successful and the vehicle has demonstrated hundreds of hours of live autonomous operations to thousands of people from industry and the public. As a result of the exposure and success of the project, we have expanded its focus to demonstrate how various technology components can be utilised to gain benefits in other areas of industrial operations. These include asset tracking, vehicle usage analysis, pedestrian detection and infrastructure profiling. Each of these components was derived from the core autonomous vehicle technology suite and has shown a high potential for improving safety and efficiency of vehicle-related operations, and improved diagnostic processes for measuring deformations of bakes and furnaces. The autonomous vehicle project and its extended technologies are described in this paper.

Aug 1, 2013

By J. Forster, C. A. Pickles, Mackowiak. K.

The future development of nickel laterite deposits is crucial with regards to satisfying impending nickel demands. The commercial implementation of new hydro/pyrometallurgical processes in recent years has led to significant improvements in the extraction of nickel from the laterite ores. One potential alternative pyrometallurgical processing route would be to selectively reduce the nickel and produce a concentrate with nickel contents similar to those attainable in the conventional flotation of sulphide ores. However, even bench scale studies have not yet been able to produce a high grade (>15% nickel) concentrate from a low grade laterite ore. The present research involved the microwave vacuum reduction roasting of a nickel laterite ore to yield a high grade concentrate, rich in nickel. Firstly, the effects of temperature and pressure on the nickel grade and recovery were investigated using a thermodynamic model. Secondly, briquettes containing a mixture of charcoal and a low grade silicate nickel laterite ore were reacted in a microwave vacuum system. The experimental variables studied were the input microwave energy, pressure and absorbed microwave power. Thirdly, the ferronickel in the reacted briquette was concentrated by magnetic separation and nickel grades of up to 21% could be achieved.

Jan 1, 2015

By A. Desbiens, A. Pomerleau

During the summer of 1994, a new PID-based control strategy was installed on line B of the grinding circuit at the Kidd Creek Division of Falconbridge Ltd. Part I of this paper described the methodology used to select the appropriate control strategy using a phenomenological dynamic simulator. Part II presents the implementation of the control strategy. Prior to the controller installation, it was necessary to solve various problems related to the process, such as a cyclic behaviour of the rod mill feed tonnage, a problem related to the mill water source and the calibration of the flowmeters. Once these problems were solved, the control strategy was accomplished in two steps. Step 1 corresponds to the installation of control loops to regulate the pump box level and the cyclone overflow density. Step 2 describes the implementation of a loop to control the cyclone feed density. According to Part I, a loop to control the circulating load is also part of the original design. However, reasons are given to explain the rejection of this loop. For both steps, technical procedures such as filtering, process identification and controller tuning are detailed. Finally, the operator’s interface is briefly described.

Jan 1, 1997

By W. A. Jones

"The Hollinger gold mine is in the Porcupine area, Cochrane district, in northern Ontario. The adjacent town of Timmins, which has a population of 25,856, lies 490 miles by railway north of the city of Toronto.The property was staked in the late summer of 1909. The original four claims were staked by Benjamin Hollinger, after whom the mine was named. Development commenced in the autumn of 1909 and mill construction in the winter of 1910. A catastrophic forest fire swept the district in 19ll, destroying the surface plant, so that the original 300-ton mill was not completed until June 1912. From that date up to December 31, 1945, 44,280,750 tons of ore have yielded 13,636,796 oz. gold and 2,613,354 oz. silver. The total value of the production has been $363,638,315.0REBODIES AND MINERALIZATIONThe orebodies consist of quartz veins, stringer lodes, and scockworks, with associated pyritized wall-rocks. The width of individual orebodies, as exposed by mining operations, ranges from 1 to 70 feet and averaged approximately 10 feet in 1942. The vein system forms a complex pattern in a favourable zone, which in places is 6,000 feet long and 4,000 feet wide. The deepest level being developed is 5,150 feet below the surface. Few veins are persistent for long distances, although some are continuous for more than 1,000 feet longitudinally and vertically.The host rocks consist of a closely folded series of Precambrian lava flows of Keewatin age. These are schistose and hydrothermally altered, but are believed to have originally been of intermediate to basic composition. The schistosity strikes N.70°E. and dips to the south at 75° to 80°. The structure of the formations is complex, but in the principal ore-bearing zone the general dip of the flows is to the south at a slightly flatter attitude than the schistosity."

Jan 1, 1954

By Michael E. Charles, Jaroslav J. Vocadlo

"The hydraulic transport of solids through pipelines can have many advantages over other modes of transport. Numerous successful applications both within plants and over longer distances have demonstrated the technical and economic feasibility of slurry pipelining. Solids successfully transported include kaolin, coal, iron ore, gilsonite and limestone, and others, such as sulphur and potash, are likely to be transported in Canada in the near future. However, though the technology of solids pipelining is quite advanced the underlying principles have not yet been formulated past the semi-empirical stage. The main objective of this paper is to present a discussion of the important technical and economic considerations in the design of so lids pipeline systems by reference to typical data. The Worthington slurry pumps and pilot facilities are briefly described."

Jan 1, 1972

By M. A. Nagle

Various strategic projects were carried out in 2002 to increase the capacity of Teck Cominco's integrated zinc-lead smelter at the Trail operations site in British Columbia, Canada. The lead smelter treats the iron residue from the zinc plant and optimizes the overall zinc recovery. This paper summarizes two options that were considered to reduce the zinc content in the leaching iron residue. The first option involved increasing the capacity of an existing hot acid leach circuit up to the iron loading constraints of the circuit. The second sought to maximize the hot acid leach capability by separating the ferrite-rich solids, followed by aggressive hot acid leaching (>100°C) and subsequent iron precipitation. Different forms of iron precipitation were reviewed in order to determine the most effective and economical approach. Among these, was a novel high temperature ferrite conversion process. The technical results and selection criteria are presented together with possible ways to integrate the process concepts into the current sulphide leaching plant circuit. The first option was selected for implementation and is currently being operated successfully.

Jan 1, 2006

By A. S. Dawson

Introduction The purpose of this paper is to discuss, in a general way, the application of geological principles in the exploration for, and development of, deposits of industrial minerals. Mention of geological factors pertaining co specific minerals will be by way of illustration only. Since many prospectors are little acquainted with the geological setting and mode of occurrence of deposits of these minerals, some prospecting possibilities in the field will be pointed out. Geology is a tried and proven tool in the search for and exploitation of metalliferous deposits and of oil and gas fields, but, so far at least as Canada is concerned, only very rarely has a directed, intensive search been made for deposits of industrial minerals. Examples might be cited, however, where, in other countries, such investigations have yielded rich rewards. Thus, development of the vitally important potash deposits of New Mexico was the result of a deliberately planned programme of geological investigation, first by United States Government agencies, and later by private interests. War or the threat of war, or peace-time industrial expansion, can render concentrated exploration for specific minerals desirable or even essential. Such exploration is, primarily, a geological problem. Admittedly, there is in general less scope for the application of geology in the search for, and development of, deposits of industrial minerals than of metalliferous minerals, oil, etc. Where the latter are concerned; the objective of exploration is to find a material that is valuable, within broad limits, no matter where it is located or how it occurs. The unit value of the material is limited only by the amount of the valuable constituent in the formation- its possible upper limit is tremendously high. On the other hand, many industrial minerals constitute in themselves 90 per cent or more of the formation- their amount cannot increase and their unit value is commonly low. Moreover, for commercial exploitation, the deposit must, in general, be reasonably close to markets or to plant or other facilities for processing the raw material, since, owing to its low value, this cannot be transported any great distance. As a consequence, intensive geological search for and investigation of such deposits has been restricted to industrialized areas. Obviously, however, it is good insurance for any operator to understand the geological background of his deposit, particularly in the case of new developments.

Jan 1, 1949

By S. Fabich

Since the very beginning of Polish copper mining, special consideration of sink shaft techniques through highly saturated Cenozoic rocks was required. Shaft freezing has been chosen as a method to consolidate these rocks. Due to the rock mass structure and water inflow potential, shaft sinking without freezing was considered dangerous. In the course of time, rock mass freezing technology and experience were evolved and this technology became safer and more reliable. New techniques appeared not only in the technical method of freezing, but also in the matter of designing. Computer aided techniques allow engineers to make a detailed analysis and view of freeze wall development. Nevertheless it is important to determine basic thermal rock properties. In this paper, the evolution of knowledge and engineering experience taken in Polish copper mines and current knowledge level in that matter were shown.

Aug 1, 2013

By S Grönstrand, C. Perez, A. B. Yañez, F. Coddou, P. Morales, H. Elgueta

"The TankCell® 300 forced air flotation cell designed and built by Outotec, with active volume of over 300 m3, was installed at Codelco’s Chuquicamata concentrator in September 2008. After that, a program was conducted, where the new cell was tested against the plant’s existing flotation cells of type TankCell® 160, with an active volume of over 160 cubic meters.Testing program was exhaustive and detailed. Grade-recovery curves for each setup were reported, along with recoveries by particle size. Secondly, operational characteristics like air feed and froth height setpoints, and power consumption are compared side-by-side. As the third topic, gas dispersion characterization included velocity mapping, holdup, bubble size and bubble surface area flux operating range. The fourth area of interest was the retention time distribution (RTD) of the 300 and 160 m3 cells in comparison. A detailed campaign using radioactive tracer tests was conducted to clarify this.All of the investigations mentioned above are reported in separate papers for more detail. The aim of this paper is to collect the key findings, and present them in real terms, always referring to operability and metallurgy of the cells. It is destined for people designing new plants and to those improving and expanding existing ones. The most frequently heard question is: will the new large cells operate at same efficiency as the smaller ones. In short, the answer is: NO. They operate at improved efficiency!INTRODUCTIONIn the last two decades of minerals processing, there have been three dominant trends of development in the flotation technology: equipment scale-up, cell characterization and circuit modeling. Equipment scale-up has been rapid in the past two decades. In the year 1990, the largest flotation cell in use was 50 cubic meters of size. This year, 300 cubic meters is the largest installed cell. Characterization of flotation equipment and circuits is a very popular subject nowadays and has helped many operations to improve their recoveries through better control strategies, for example by using optimized air feed and level control profiles (Gorain, 2005), (Doucet, Gomez, Finch, 2006), or through better maintenance (Coleman, Urtubia, Alexander, 2006). Characterization work is closely linked to circuit modeling. The aim is to produce sufficient amount of data to allow reliable model building. These models are then used to design new circuits and to improve existing ones. So in summary, these three lines of development have slightly different aims – from capital and operational cost to performance optimization. Ultimately, they converge in the same end result – maximizing the profitability of the operation. Following chapters will summarize the extensive test work and scientific studies at Codelco Chuquicamata. The aim was to compare a TankCell® 300 cell, with nominal volume of 300 m3, against two TankCell® 160 machines, with 160 m3 volume in each. The work should yield answers to questions: does the larger cell produce similar results – is the scale-up successful?"

Jan 1, 2010

By Y. G. Seredkin, A. A. Vasiliev, A. Y. Senchenko, A. V. Aksenov

"Autoclave oxidation, bacterial and chemical liberation, roasting, acid oxygen processes, atmospheric oxidation prior to cyanidation are applied to process refractory sulphide concentrates. It is obvious that the processes with the maximum effect regarding gold recovery are those in which complete destruction of sulphides takes place and gold becomes accessible for further cyanidation through liberation from sulphide “capsula”. But the significant recovery increase is often accompanied by a process complexity, high expenses for equipment purchase and maintenance. It makes material processing costinefficient. Process optimization has led to progress in ultrafine grinding, bacterial and autoclave oxidation processes. In our opinion sulphide atmospheric oxidation processes are the most interesting as oxidation there runs without high temperature (up to 100°?) and excess pressure (open units), and with acid environment close to neutral. The process of sulphide concentrates treatment named “Albion” (Albion Process™) represents a combination of ultrafine grinding and oxygen oxidation without pressure and external heating. The process has a number of advantages: sodium cyanide consumption decrease during gold leaching and high ecological compatibility. TOMS institute in collaboration with Glencore Technology Pty ltd (Australia) tested Albion technology aiming at liberation of finely disseminated gold from flotation concentrate produced from refractory ore of one Russian deposit. The testing has shown that Albion technology makes it possible to process refractory products with quite small capital investments. It enables involving medium and small refractory gold deposits into processing.INTRODUCTIONThe considerable part of the world Au-bearing reserves is present by refractory ores with finely disseminated gold. Gold in such ores is often associated with sulphide minerals and locked in so called “sulphide capsula” since it is closed inside dense sulphide grains and inaccessible to recovery by cyanidation. To treat refractory sulphide concentrates containing gold a number of processes were developed and they can be divided into three groups (Figure 1)."

Jan 1, 2016

By N. R. Paterson

"More than a dozen AEM systems are currently being used in the routine exploration for massive sulphides. The systems differ from one another in minor respects, but fall into four main categories: rigid-coupled in-phase/quadrature systems; towed-bird, single-component systems; differential systems; and passive systems.Although field tests are important in demonstrating the performance characteristics of the AEM/airframe assembly (noise-levels, coupling effects, etc.), more meaningful evaluations can be made through physical or computer modelling. The latter approach has been used to compare the response of twelve AEM systems to both vertical and horizontal sheets, simulating a large orebody and a con-ductive overburden respectively. The effects of height changes are also studied.The results demonstrate that each AEM system has its own particular advantages and disadvantages. The relative importance of these is a matter for the geophysicist to judge, on the basis of specific geological and environ-mental information. Data currently available on AEM systems are adequate to permit an objective evaluation of the systems for a particular exploration program."

Jan 1, 1971

By G. Graves, J. A. Walker

"Abstract - The Mount Fronsac North volcanogenic massive sulfide deposit is the most recently discovered massive sulfide body in the Bathurst Mining Camp. The deposit occurs within a sequence of intercalated fine-grained felsic tuff and sedimentary rocks (Little Falls member), at the top of the Nepisiguit Falls Formation. Aphyric to sparsely feldspar-phyric rhyolite and related volcanic rocks of the Flat Landing Brook Formation overlie the host sequence. The massive and semimassive parts of the deposit have a north-south strike length of 525 m and a dip of ~45°E; the deposit is continuous downdip for 600 m, and thickness varies from 2 to 20 m. The deposit contains an estimated geologic resource of 14 Mt of low-grade, semimassive (>60%) to locally massive sulfides, and includes a high-grade zone of 1.26 Mt grading 7.65% Zn, 2.18% Pb, 0.14% Cu, 40.3 g/t Ag, and 0.40 g/t Au. The semimassive to massive sulfide intersections occur in an envelope of quartz-sericite±chlorite schist, which is interpreted to be intensely deformed felsic tuff. This sequence has a maximum thickness of 140 m and contains significant (up to 50%) fine- to coarse-grained disseminated pyrite. The pyritic envelope has a strike length of 900 m and extends over 1000 m downdip. Massive sulfides are found throughout this alteration envelope, but more commonly occur at or near the upper contact. The significance of the discovery of this deposit is that it represents a near surface discovery of a large tonnage sulfide body in a mature mining camp, one in which the possibility of discovery of a new shallow deposit had been all but discounted. This opens the possibility for future discoveries in this part of the Bathurst Mining Camp. Sommaire - Le gîte de sulfures massifs volcanogènes du Mont Fronsac Nord est la découverte de sulfures massifs la plus récente dans le Camp Minier de Bathurst. Le gisement est situé dans une séquence de tufs felsiques à grains fins interlités de roches sédimentaires (membre de Little Falls, au sommet de la Formation de Nepisiguit Falls. La partie massive et la semimassive s’étendent du nord au sud sur 525 m et ont un pendage de ~45°E; le gisement est continu sur 600 m en angle de chute et son épaisseur varie de 2 à 20 m. Le gisement contient une ressource géologique évaluée à 14 Mt de sulfures semimassifs (>60%) localement massifs à basse teneur, incluant une zone à haute teneur de 1.26 Mt titrant 7.65% Zn, 2.18% Pb, 0.14% Cu, 40.3 g/t Ag, et 0.40 g/t Au. Les intersections de sulfures semimassifs à massifs se situent dans une enveloppe de schiste à quartz-sericite ± chlorite interprétée comme un tuf felsique intensément déformé. Cette séquence contient une quantité importante (jusqu’à 50%) de pyrite disséminée dont le grain varie de fin à grossier et son épaisseur maximale est de 140 m. L’enveloppe pyriteuse s’étend latéralement sur 900 m et a été tracée jusqu’à 1000 m en angle de chute. Des sulfures massifs sont trouvés partout à l’intérieur de cette enveloppe d’altération, mais ils sont plus fréquents près du contact supérieur. L’importance de cette découverte tient à ce qu’elle est un exemple d’un gisement à fort tonnage nouvellement découvert à une faible profondeur dans un camp minier mature, i.e., un camp ou l’on ne croyait plus qu’il était possible de trouver un gisement près de la surface. Ceci ouvre la porte à la possibilité d’autres découvertes dans cette partie du Camp Minier de Bathurst."

Jan 1, 2006

By R. C. Gilmore, J. F. Brune

"Pulverized limestone rock dust used in United States underground coal mines to prevent and suppress coal dust explosions must easily disperse by forces of a methane or coal dust explosion. Moisture in the mine environment causes caking of the dust. Colorado School of Mines researchers performed dispersibility tests in a full-size explosion test drift. Tests included conventional, hydrophobized, and rock dust approved for German mines. Conventional and German standard rock dust products partially agglomerate, which may not be effective in suppressing a coal dust explosion, while hydrophobic rock dust retains better dispersibility.INTRODUCTIONA coal dust explosion devastated the Upper Big Branch mine in 2010 resulting in the death of 29 miners, the worst mining accident in the United States since 1972. The explosion propagated through approximately 65 km of active mine workings, but was extinguished in areas that had been properly rock dusted (Page, 2011). Researchers have long studied and established the ability of inert limestone rock dust to suppress coal dust explosions, see Richmond et al. (1975), Cybulski (1975), and Sapko et al. (2000).To be effective, rock dust must contribute to a total inert content of > 80% by weight and 100% of rock dust particles must pass through an 850 µm sieve, while 70% of the rock dust must be finer than 74 µm. This is established in US regulations 30 CFR §75.2. Dry rock dust is a nuisance that prevents mining work downwind from rock dusting activities. To overcome this problem, dust manufacturers have proposed applying the rock dust as a wet slurry or foam. After drying, manufacturers expected the slurry or foam-applied dust to have the same explosion suppression capabilities as dry-applied rock dust.Researchers at the Colorado School of Mines (CSM) designed and built a full-scale, underground Explosion Test Facility (ETF) at the CSM Edgar Experimental Mine in Idaho Springs, Colorado about 20 miles west of the CSM Golden, Colorado campus. To disperse the different rock dust products, researchers produced an air pressure pulse using a mesh array of PETN detonation cord. This method is simpler, more reproducible and safer than other methods considered, including methane-air explosions and a compressed air cannon. The detonation cord blasts produce a wind velocity of 30 to 50 m/s, the minimum velocity at which coal dust explosions can propagate, based on research by Nagy (1981) and Cybulski (1975)."

Jan 1, 2019

By Thom Sedun

No sector of the mining industry is more closely tied to local communities than aggregates. Noise, dust, traffic, visuals aesthetics and environmental impacts all fall under the purview of neighbours, local governments and nongovernment organizations. It is no surprise that aggregate operations may not be welcome neighbors in many communities. In British Columbia (BC), the regulatory environment for aggregate operations includes a local component of municipal bylaws and land use-planning in addition to the usual suite of federal and provincial statutes that apply to its sister mining sectors. Additionally, under common law aggregate extraction is not considered to be a land use subject to land use zoning, and some aggregate processing activities can be regulated by zoning. Often traversing multiple local government jurisdictions, aggregate producers find themselves negotiating not only local traffic, but also a mosaic of regulatory environments. There is an opportunity in this present situation to facilitate the application of current technology and practices in the mitigation of many community and environmental concerns associated with aggregate operations. Moving a bulk commodity is a volume-based business, and operators often don?t have time for matters that don?t directly or obviously affect the bottom line. Regulatory agencies often play multiple and complex roles with respect to their industry, not the least of which is the fiduciary role. Balancing how and when to assist an industry is often a difficult decision. For the aggregate industry in BC, the Ministry of Energy and Mines saw an opportunity to assist not only aggregate operators, but also regulatory agencies, local governments, and the general public. Through investing in the Aggregate Operators Best Management Practices Handbook (handbook) project, the Ministry of Energy and Mines (MEM) believes that it will realize a return of upheld community values, enhanced environmental protection, improved regulatory compliance, reduce disputes and a stronger provincial aggregate industry. It is the intent to publish the handbook electronically through the MEM website later this year.

May 1, 2002

By H. R. Stockford

"A pyroxenite-carbonatite complex containing extensive pyrochlore mineralization was discovered during January, 1966, within an exploratory license area held by Consolidated Morrison Explorations Limited. Located 32 miles south of Moosonee, Ontario, the deposit was found under 100 feet of glacial till and Paleozoic sedimentary cover using airborne and ground magnetometer surveys. Exploratory and detailed drilling, totalling 47,625 feet in 85 holes, was completed in outlining the deposit to a maximum depth of 900 feet. Pyrochlore reserves are estimated at 62,000,000 tons averaging 0.52 per cent Cb,05 to a depth of 825 feet. Included in this tonnage is a high-grade section containing 10,000 tons per vertical foot grading 0.82 per cent Cb20 5• The deposit is still open at depth and the intrusive complex has by no means been fully explored.The columbium (niobium) mineralization occurs in a lineated calcite-dolomite host rock which has been intruded along a fault zone within a northeast-trending granulite belt. Potassium-argon dating indicates an age of 1655 million years.Preliminary studies suggest that the complex was intruded in a series of pulses in the form of a partially crystallized mush. The James Bay intrusive is unusual in that it is linear in form and contains only two main rock types - p•yroxenite and carbonatite. Nepheline-bearing syenites and associated rocks are notably absent. Moreover, the pyrochlore is essentially non-radioactive and free from many of the impurities generally associated with other pyrochlores. A test shaft to investigate soil conditions and to provide a 250-ton bulk sample was completed during 1968. Subsequent pilot-plant operations indicate that good quality pyrochlore concelttrates can be produced from this deposit."

Jan 1, 1972