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By P. Scinto, P. Hudson

"Modern day ore bodies are becoming increasingly harder, more abrasive and lower grade. The Mako deposit is located in Senegal and consists predominantly of primary mafic and felsic lithology that are both very competent and very abrasive ores (Axb < 30, BWi >20 and Ai >1.0). The deposit was initially discovery in 2010 and the Toro Gold management team fast tracked the Mako Project through development and into production to achieve its first gold pour in January 2018. The comminution circuit comprises primary crushing single stage SAG milling with recycle crusher (1oCR SS-SAC). The mill reached design throughput and grind size seven weeks after first ore. The Mako project marks another successful international application of single stage milling, which represents a simple and easy to operate comminution circuit for small-to-mid size projects with a low capital cost. This paper describes the ore interpretation, comminution modelling, grinding circuit selection and design, as well as an overview of the commissioning and ramp-up of the mill.INTRODUCTION The Mako Gold Project is operated by Toro Gold Ltd., which holds a 90% interest in the project. The project is located in south-eastern Senegal in the Kedougou region, close to the Gambia river and township of Mako. The Mako deposit lies in the “Kenieba Window” of eastern Senegal and western Mali, which hosts a number of gold mining operations and development projects. The Mako Gold Project has an estimated life of 8 years with overall recoverable gold estimated at 924 koz. The process plant is designed to treat 1.8Mt/a of ore and produce 128 – 143 koz of gold per annum. Lycopodium Minerals Pty Ltd (Lycopodium) was appointed to provide feasibility studies and EPCM services for the greenfield project. Forming part of consultancy services provided by Lycopodium, Orway Mineral Consultants (OMC), a subsidiary of Lycopodium, was involved in the design, commissioning, ramp up and ongoing post commissioning support of the comminution circuit."

Jan 1, 2019

By R. P. Viljoen, A. D. Scheglov, A. L. Sokolov

"Abstract -The distribution of mineralized provinces is analyzed on the basis of their genetic link with specific blocks of the earth&apos;s crust including ancient platforms, mobile belts and zones of tectonic­ magmatic activation. Mobile and fold belts surround the Siberian platform in Russia and the Kaapvaal craton in South Africa, with decreasing age zoning away from ancient platform margins. The main differences in the geological development of the two cratonic areas are: (1) the long period before the final stabilization of the Siberian platform (3600 Ma to 1600 Ma) and the comparatively short period of time for the stabilization of the Kaapvaal craton (3600 Ma to 3050 Ma) and (2) the intensive multiple activation of the marginal zones of the Siberian platform and the tectonically­ controlled, magmatic sedimentary, intracratonic activity, typical of the Kaapvaal craton. Mineralization of the Siberian platform is largely characterized by marginal reactivation zones of differing ages although mineralized intracratonic Cu-bearing basins of Proterozoic age are also known. Mineralization of the Kaapvaal craton is mainly related to the formation of the intracratonic basins i.e., Witwatersrand (Au, U) and Transvaal (Au). The latter is characterized by multi-age volcanic-intrusive activity including the emplacement of Bushveld Complex (Cu, Ni, Pt, Cr, Au, V). The Siberian platform is characterized by the prolonged development of inherited mineralization from Archean until the late Mesozoic. The main period of mineralization in the Kaapvaal craton is restricted to the middle Proterozoic.The Baykal-Patomskaya and Namaqua-Natal mobile zones occupy similar positions adjacent to the Siberian and Kaapvaal cratons, respectively, and demonstrate similar modes of metallogenic development: i.e., the early formation of exhalative Pb-Zn-Cu deposits during the early stage and magmatic Cu deposits during the late stage. The more remote mobile belt near the Siberian plat­ form, the Trans-Baykal, is characterized by intensive multi-age mineralization (Wo, Mo, Sn, fluorite), related to a period of tectonic-magmatic activation. The Saldania Belt occupies a similar position near the Kaapvaal craton but is known for its poor Au, and Cu rnineralization. lt does, however, have some similarities with Trans-Baykal Belt in regard to Mo-W bearing granitoids.The phenomenon of interference of geosynclinal, orogenic, platform, and tectono-magmatic activation regimes is known for the Russian section of the Pacific Ocean Volcanic Belt."

Jan 1, 1994

By Robert B. Parsons

"Once all the hullabaloo about Finance Minister Wilson&apos;s April 27 budget died down (or was it an April 26 budget?), the pain of the budget papers began to sink in. Individuals and corporations will have to dig deeper and pay more taxes - and government will continue to dig deeper and spend more. The irony of the situation is that higher tax rates actually make flow-through shares more attractive as a tax-deferral investment - a bittersweet ""bravo"" for the mining industry.INTRODUCTIONFor the first time in Canadian history, a major budget address has taken two days to deliver. Of course, it&apos;s not a case of long-windedness, but rather a case of a hastily called press announcement on April 26 in response to a budget leak, followed by a formal budget speech on April 27.The general reaction of the business community to the budget was to the effect that the tax hikes are acceptable, but the government&apos;s failure to curb spending is less than acceptable. Mr. Wilson&apos;s reported response indicated that the government had never promised to cut spending, and that increased government spending would actually benefit the country. That age-old debate will doubtlessly continue for generations.In any event, three noteworthy components of the budget papers are:• Personal income tax rates increase effective July I, 1989;• A ""large corporations tax"" (in effect &apos;a corporate ""minimum tax"") is effective July I, 1989; and• Federal sales tax increases are effective from June 30, 1989, to be replaced by a national sales tax in 1991.A brief overview of these and other budget proposals follows."

Jan 1, 1989

By J. Janeson

Wall control at the Pipe Open Pit is of primary importance in ensuring the long-term stability of the operation, while keeping costs to a minimum. Blasting techniques have been adapted to the variations in competence and structure of the wall rocks. A portion of the perimeter wall is being developed in incompetent peridotite . A recent change in pit slope design provides a wide safety berm on alternate benches. A support program which consists of pinning the crests of wide berms with vertical reinforced concrete dowels and horizontal bolting of walls shows evidence of increasing the stability of the pit walls. This paper describes the blasting and support techniques which are contributing to successful wall control in the Pipe operation.

Jan 1, 1979

By Scott Honan, Tassos Grammatikopoulos, Mike Johnson, Kelton Smith, Niels Verbaan, Ernesto Bourricaudy, Eric Larochelle, Rick Sixberry

"NioCorp is developing the niobium/scandium/titanium Elk Creek carbonatite resource deposit. The carbonatite phase contains significant niobium (0.71% Nb2O5), titanium (2.68% TiO2) and scandium (72 g/t) and is composed predominantly of calcite, dolomite and ankerite. Niobium is mostly (80%) contained in the pyrochlore and the balance in various Fe-Nb-Ti oxides, which also host most of the titanium. Scandium is distributed homogeneously throughout the ore mineral assemblage. The process flowsheet recovers separate niobium, titanium and scandium products. Scandium is extracted from whole ore hydrochloric acid leach solutions through solvent extraction, and is further refined through a re-leach and precipitation process. Scandium leach residues are treated with sulphuric acid to recover separate niobium and titanium precipitates. Both hydrochloric acid and sulphuric acid reagents are recycled within the flowsheet. This paper will discuss key bench and pilot test results (focusing on the scandium flowsheet) and will present a conceptual flowsheet developed by the project team for NioCorp at SGS Minerals.INTRODUCTION NioCorp is developing North America's only niobium/scandium/titanium project. The Elk Creek project is located near Elk Creek, Nebraska, and is the highest grade niobium project in North America and the largest prospective producer of scandium in the world. These elements are unique and valuable superalloy materials that are strategic and critical to many industries and national defense technologies. The project includes the Elk Creek Carbonatite (the Carbonatite) that intruded older Precambrian granitic and low to medium grade metamorphic basement rocks. Both the carbonatite and Precambrian rocks are interpreted to be unconformably overlain by approximately 200 meters (m) of Paleozoic marine sedimentary rocks of Pennsylvanian age. As a result of this thick cover, there is no surface outcrop within the Project area of the carbonatite, which was identified and targeted through magnetic surveys and confirmed through subsequent drilling. The available magnetic data indicate dominant northeast, west-northwest striking lineaments, and secondary northwest and north oriented features that mimic the position of regional faults parallel and/or perpendicular to the Nemaha Uplift."

Jan 1, 2017

By Mousa Mohammadi

Due to operational advantage of dragline in simultaneous excavation and back-filling, the equipment has gained vast importance in open-pit mining. Besides, absence of auxiliary haulage units and a myriad of other benefits are also credited in favor of excavation of muck piles by the draglines. However, the aspects of production, productivity and economics are of utmost significance in dragline operation and planning. In this light, the present paper is an endeavor to analyze availability and utilization of dragline operations. The paper presents a good amount of data for 4-draglines operating in one of the major opencast projects in India. The study reveals the trends of availability and utilization of these draglines during last 11-years. Furthermore, the study also highlights the salient reasons for loss of available hours and for idling of the draglines. Some startling information and facts have been illustrated in form of graphs and pie charts.

Aug 1, 2013

By M. Abouhamad

According to the Canadian Urban Transit Association (CUTA), 140 Billion CAD is required to maintain, rehabilitate, and replace subway infrastructure between 2010 and 2014. The current practice adopted by transit authorities for prioritizing subway stations for rehabilitation is based on the station structural needs. While this classification is reflective of station condition, other factors, such as station size, location and passenger capacity, play an important role. The criticality of a station is an index that represents the functional importance of a station depending upon a set of identified factors. The system criticality is based on several attributes, such as station location, size, and nature of use. This paper presents a novel method of clustering subway stations for rehabilitation priority based on their criticality level. The different stations in a subway network are rated according to their relative importance against predefined attributes. The weights and scores of the attributes are computed with the help of experts and current subway network data. The analysis is done using the Fuzzy Analytic Network Process (FANP) to accommodate the subjectivity of human judgment as being expressed in natural language which entails ?fuzziness? in real-life problems and account for the interdependency between the selected attributes. The output of the model is a criticality based clustering of subway stations. The proposed framework helps authorities prioritize stations for rehabilitation and highlight stations with more criticality for a more robust asset analysis.

Aug 1, 2013

"Real time analysis of conveyed bulk materials can be used to improve process performance by reducing variability and upgrading ore quality through selective removal of increments of flow that do not meet appropriate selection criteria. This paper focusses on proven Prompt Gamma Neutron Activation Analysis (PGNAA) and microwave transmission technologies used to representatively measure conveyed ore quality in real time so that meaningful decisions can be made between the mine and mill. This enables the effective removal by bulk diversion of small increments of conveyed flow such as waste, highly deleterious material or sub-economic material from the mill feed. Improved ore quality in plant feed optimises process performance, reduces processing costs and minimises tailings generation. Analysis is unaffected by particle size, dust, layering or segregation, mineralogy and belt speed. Technologies are explained and performance examples given from installations in copper and iron ore. The technology has been used successfully in bulk sorting for over twenty years typically using measured increments of a few minutes. Improvements in technology and calibration performance have resulted in accurate measurements over increments of thirty seconds and below.INTRODUCTION Ore quality variability exists on a number of scales. Block model grades represent a few hundred to many thousands of tonnes. Grade control at the mine occurs on a scale typically down to the size of a haul truck, which may be a few hundred tonnes. Highly variable ore quality is detrimental to process efficiency and effectiveness. Processing waste or low grade ore when higher quality feed is available represents a lost opportunity to generate higher revenues earlier in the operational life. Measuring ore quality accurately over short time increments during conveying enables small increments to be measured and diverted according to their quality. The paper explains the technology and benefits. Neutron irradiation techniques were considered potentially suitable for conveyed bauxite measurement by Beurton et al, 1995. Tran & Evans (2001) concluded there was no equivalent technology to Prompt Gamma Neutron Activation Analysis (PGNAA) in terms of material penetration power. PGNAA was evaluated by Nelson & Riddle (2003) for possible use in the phosphate industry and recommended its use for further characterisation of the mine’s various ore types to improve stockpile allocation and grade control. Cottle (2007) discussed test work for an iron sinter application and Delwig et al (2011) described the successful installation in 2009 and performance of PGNAA for base-to-acid ratio control in sinter feed with the analyser output used to control lime addition. Geoscan (PGNAA) works very well on iron ore and can “improve control over what is happening in the plant” and that comfort can be provided in knowing that the product is on-spec according to Minnett (2010). PGNAA is not yet used in the minerals sector for tariff purposes as has occurred since 2000 with Coalscan (PGNAA) in coal (Minnett, 2010)."

Jan 1, 2017

By G. Favini

A Bayesian decision model of minimun risk, based on the probability and costs of mine discoveries and non-economic projects, is presented for massive sulphide exploration in the Canadian Shield. The sample used for the model is composed of data relating to forty mines, sixty non-economic sulphide occurrences, and sixty occurrences of graphitic and pyritic material. These economic and barren samples consist of drill-tested occurrences which were, in varying degree, characterized by conductivity anomalies. Given the large size, the reliability and the homogeneity of the data base available for massive sulphide exploration, it is shown that certain statistical models can and should be utilized as a tool for decision-making by explorationists. Given this data base, information theory tells us that only those signals that are independent of one another will transmit information with minimum error. An ensemble of six significant multilevel signals, markedly independent of one another and consisting of numeric and geometric form descriptions derived from Bouguer anomaly, aeromagnetic and physiographic maps, were identified and evaluated by case studies. The use of these signals as input in a simple statistical procedure, or in a carefully planned and experienced visual appreciation scheme, can be of significant aid in decisions concerning the choice of favourable areas or sectors to explore in detail. The method of discriminant analysis is theoretically and practically suited for the statistical modelling involved. By way of a simulation on our statistical model, the efficiency of the model and of the underlying criteria is determined for historic cases and, by inference, for its validity in future exploration. An approximate optimized solution is derived from the model which suggests that over 90% of the known ore could be found by screening, according to a model such as that herein described, and drilling only 30% of the targets (mostly barren) normally identified and tested in current and past exploration.

Jan 1, 1979

By N. Campbell

"The fault under consideration follows a northerly trend past the west; side of the original settlement of Yell ow knife; which is situated 600 miles; north of Edmonton and 400 miles from the Northern Alberta Railway; terminus at Waterways; Alberta. The mining properties chiefly concerned; include the southern part of the Giant claims; on the east side of the fault; and the Con-Rycon-Demelt claims; on the west side 3 1/2 miles to the south.; Geological data were also obtained from the eastern part of the A.Y.E.; property; which lies south of the Giant claims; and from the Negus; Meg; Yellorex; and Kam properties; which are south and southeast of the ConRycon-; Demelt claims (see Frontispiece; also Fig. 5).Recognition of the major faults in the Yellowknife Bay area, including the West Bay fault, which appears to be the greatest, resulted from the work of A. W. Jolliffe (formerly of the Geological Survey of Canada) in 1935 and subsequent years. It has been stated with little exaggeration that these faults rank with the largest known steeply dipping dislocations of the earth's crust.In the winter of 1939, a mineralized shear zone named the 'Creek vein' was found on the Giant property. It was noted that the space relationship between this shear zone and a body of quartz-feldspar porphyry is roughly the same as that between the Con C-4 shear zone and a body of acid flows lying north of the Con property. Coupling this relationship with the assumption that the movement along the fault is dominantly horizontal, it was postulated that the Giant shear zone represented the faulted extension of the Con C-4 shear zone.As geological information became more extensive, certain weaknesses in this concept became apparent, and when spectacular orebodies were discovered on the Giant property in 1944 the question of possible faulted extensions became an important consideration. Consequently, in the spring of 1944, an extended investigation was undertaken, the results of which are embodied in this paper."

Jan 1, 1954

By Erwin L. Zodrow

"IntroductionThrough an extensive coal sampling project in the Sydney coalfield of Nova Scotia during 1981 - 1984 involving a majority of the mineable coals (Zodrow, 1985, Fig. 1), a sizeable inventory on trace, minor and major metals was established. In this paper, results of studying the inventory are summarized, concentrating mainly on the relationship that exists between metal variations and thickness of coal channel samples (i.e. trends) and on explaining the trends in geochemical and sedimentological terms. As an over-all conclusion the Everglades peat of Florida is proposed as a modern-day analogue to Upper Carboniferous peat swamp development that took place in the Sydney Basin.Data InventoryFor this study 17 channel samples were cut , 8 cm to 14 cm channel width and 8 cm to 10 cm depth, from 10 successive coals which in stratigraphically descending order are as follows: Point Aconi (3), overrider Lloyd Cove (2), Lloyd Cove (2), Stubbart (2), Harbour (4), Backpit (I), Phalen (,I), Shoemaker (1) and McAulay (I), where bracketed values signify the number of channel samples cut from a seam (Zodrow, 1985, Fig. I). Each channel sample was subdivided by 15 em incremental length yielding a total sample size of 137 for analysis. By appropriate modern techniques these samples were analyzed to determine concentration levels for 32 chemical elements and ash content, the average results of which are presented in Table 1.Tests were also made for Pd, Pt, Ga, Nb, Cd, Cs, Sm and W but their concentration levels in many instances hovered on the lower detection limits that were used and on this accounts are excluded from discussion. Ashing, when necessary for the determination of concentration levels, was done for 12 hours at a temperature not exceeding 450°C. Concentration levels for the elements are reported in reference to whole-coal or whole-coal equivalents and discussed on this basis. In the course of the analyses, lower detection limits received careful attention."

Jan 1, 1986

By A. S. Knight

THE breaking and handling of ore is obviously the most important consideration when the layout of a new mine is contemplated. The problem must be attacked with due regard to the claim area of the property, the dip of the orebody, the anticipated percentage of payability, the width of the reef, and the amount of dislocation anticipated by dykes, faults, or sills. Among these, as far as East Geduld is concerned, the three most important items are: Area. 2,640.5 claims. Average dip 12° (from flat to 35°) Average channel width 36 inches. We are fortunate on the Witwatersrand in &apos;chat there is usually sufficient information available from surrounding properties to determine, within narrow limits, the factors mentioned above. With this information avail-able, the choice of layout is not limited, and it will be found that on the Witwatersrand each group has developed its own technique to suit its individual requirements. On East Geduld, the layout of the property for handling ore is known as the endless-rope haulage system. Following is a brief description of the general principles followed.

Jan 1, 1942

By D. C. Crothers

"What is new in air compressors? A good deal - the designers have been keeping pace with technical developments in related fields and also contributing new techniques of their own. Plant reliability no longer requires bulky slow-speed machines. Even the reciprocating machines, which still provide the most efficient method of compressing air, have been greatly reduced in size and installation cost for a given capacity rating. New materials and fabrication techniques are being used, by most manufacturers, to produce less costly plants in total. Many packaged plants are available, which generally means a more complete assembly for shipment. This type of construction offers savings in handling and erection costs at the site. A warning is in order, however - the extent of packaging in any given plant should be investigated carefully to determine what is included and just what field costs can be realized. A suggested specification has been offered for consideration when studying comparative costs. Rotating machines intrigue many because of their potential as regard fewer wearing parts, higher speeds and hence smaller units, utilizing less expensive drivers, and lack of contamination of the compressed air by lubricants. The inherent shortcomings of these machines - lower •efficiency and capacity control - have been much improved lately, and this type of plant is now becoming quite popular. Noise control, of much concern to everyone, is another development that has received considerable attention.Systems for efficient capacity control and continuous monitoring of compressor operation offer additional reliability and low-cost operation of the modern compressed air plant. Accessory equipment and its effect on over-all plant operation is also considered."

Jan 1, 1972

Surfaces forces have been measured between gold sphere and gold-coated glass plate in xanthate solutions using an atomic force microscope (AFM). The measurements conducted in potassium amyl xanthate (PAX) and potassium ethyl xanthate (KEX) solutions showed long-range hydrophobic forces, with the force curves showing no evidence for nanonubbles on the surface. The strongest hydrophobic force was measured at contact angle of 94° with a decay length of 23 nm. The hydrophobic force became weaker at higher concentrations and after a long immersion time, which may be attributed to the xanthate species adsorbed on top of the first mono layer. The hydrophobic force became stronger when the residual xanthate solution is displaced by pure water, indicating that hydrophobic force becomes the strongest in pure water.

Jan 1, 2009

By R. J. R. Welwood, F. J. Grebenc

"Brunswick Mining and Smelting Corporation Ltd. (controlled by Noranda Mines Limited) operates two lead-zinccopper- silver mines approximately 20 miles inland from Bathurst, N.B. The principal No. 12 orebody is mined by underground methods; the second, the No. 6 orebody (6 miles away), is recovered by open-pit mining. No. 12 underground operations ar•e in two parallel massive sulphide orebodies about 400 ft apart, dipping at 75 to 80 degrees and plunging almost vertically. The initial mining phase involved longhole open stoping from the 1550 level to the crown pillar, with main levels at 150-ft intervals and sub-levels between at 75 ft. Stope dimensions average 120 ft long, 100 ft wide and 400 ft high, with alternate rib pillars as well as sill and crown pillars. Initially, ore was transferred through scram drifts below each stope by means of 125-hp electric slushers and 72-in. folding scrapers, being delivered to gravity ore-pass collection •systems feeding a primary jaw crusher below. Later, track and trackless drawpoints were utilized below most longhole open stopes and pillars. Rib pillars were recovered by longhole methods, with large blasts into a central slot and undercut, after adjacent stopes had been filled. Waste-rock stripping from No. 6 open pit has been supplied to No. 12 stopes as backfill, by means of gravityfill raises.In 1968, the decision was made to mine the remaining ore zones by mechanized cut-and-fill methods, utilizing Load-Haul-Dump equipment. Currently, approximately 60 per cent of No. 12 mine production comes from mechanized cut-and-fill mining. As before, backfill is supplied from No. 6 open pit stripping waste rock, which has been crushed to minus 6 in. The ultimate objective is to supply virtually all production requirements by mechanized cut-and-fill techniques. The No. 6 open pit, which commenced production in 1966, covers an area of 1,500 by 1,200 ft, equivalent to 41 acres approximately. Ramp roads are graded at 8.5 per cent. Each mining bench is 36 ft high and the ultimate pit will consist of 14 benches for a final pit depth of 504 ft. Present depth is 180 ft."

Jan 1, 1971

By G G. Suffel

T HESE remarks on the occurrence of strata-bound massive sulphide deposits are submitted be-cause the writer recently visited the principal Cyprus deposits (in January, 1965) and has also a back-ground of many years spent largely in detailed observation and map-ping of the Horne and Amulet ore-bodies, now largely inaccessible. They are particularly related to the Symposium papers (September Bulletin) by Hutchinson and by Roscoe. Some comments are offered on the cupriferous pyrite deposits of Cyprus. As the writer is currently reviewing the published literature on the related deposits in Turkey, a brief account of some characteristic Anatolian sulphide occurrences is given. The discussion is closed with some thoughts on the relationship between these Mediterranean sulphide deposits and those of northwestern Quebec and the Superior province in general. The geology of Cyprus, as it relates to the sulphide deposits, is well summarized by Hutchinson (1965). After visiting Mavrovouni, Skouriotissa and Limni and after much thought on the possible ge-nesis of these ores, it seems quite logical to me that he is right. They are indeed closely related to late-stage submarine volcanism.

Jan 1, 1965

By Mike Johnson, Greg Andrews, Niels Verbaan, David Dreisinger

"The Search Minerals Foxtrot project in Labrador represents a significant Canadian resource of rare earth elements rich in the sought after heavy rare earth elements (19.8% HREE/TREE). A preliminary economic assessment of the project indicated that the project is technically feasible and economically attractive. A variety of metallurgical test programs have been undertaken which have led to significant streamlining and simplification of the process flowsheet. The improved flowsheet should allow Search to reach production earlier and will use conventional processing equipment. The results of these test programs are presented and discussed in this paper INTRODUCTIONSearch Minerals Inc. (Search) is exploring and developing a number of deposits for rare earth element (REE) recovery in Labrador, Canada. The Port Hope Simpson District is in the southeast of Labrador and is highly prospective for heavy and light rare earth elements. The Foxtrot deposit sits within the Port Hope Simpson REE District (Figure 1), which is 70 km long by up to 10 km wide. The infrastructure available at Foxtrot is excellent; a deep-water port, air strip, and road and power infrastructure are pre-existing at St. Lewis. The three communities of Port Hope Simpson, St. Lewis and Mary’s Harbour are in close proximity to the site."

Jan 1, 2016

By Paul T. Fitzgerald

Risk financing solutions are emerging to fully address environmental liabilities for mining operations. Supported by specialized insurance and alternative risk transfer (ART) products, mine owners can fund, cap and guarantee the environmental liabilities and closure obligations of a mine within a financial structure that will be acceptable to regulators. An environmental risk financing program will permit an owner to transfer the liabilities and indeed the ownership of a site to a third party that has the ability and resources to responsibly execute the closure plan. A properly structured program will be financially viable for the owner and will also respond to community and environmental opposition concerns about sustainable development and the environmental legacies associated with mining activities.

Apr 1, 2005

Mineral resource development activities impact the health and well-being of many people, from workers, to families and surrounding communities. In the decade up to 2010, mining revenues increased from 6% to 14% of Australian GDP, and minerals contributed 55% of total exports, with a growth in mining employment from 1% to 1.7% of the national workforce (Connolly and Orsmund, 2011). The growth in Australia?s minerals operations is mostly located in remote areas, or in rural communities with a limited population. As a result, operations have increasingly implemented long distance commuting (LDC) programs, often called ?fly-in, fly-out? (FIFO) and ?drive-in, drive-out? (DIDO), as a staffing strategy to meet rapid industry growth in locations with limited local populations. The rapid expansion of the minerals industry has resulted in considerable public debate about the benefits and costs to all sectors of Australian society. In response to the concerns of constituencies from many parts of Australia, the Minister for Regional Australia, Regional Development and Local Government, The Hon Simon Crean MP, asked the House Standing Committee on Regional Australia on Tuesday 23 August 2011 to inquire into and report on the use of ?fly-in, fly-out? (FIFO) and ?drive-in, drive-out? (DIDO) workforce practices in Regional Australia. The recently published report highlights the national interest and the diverse opinions about this practice in Australia. Resource extraction companies have developed several options to meet the accommodation requirements of their long distance commuting workforce. In this paper, initial results are reported from an ongoing survey of FIFO (and other non-residential) resource industry workers (n = 286) in the Australian resource extraction industries. The purpose of this study was to better understand how accommodation arrangements may impact on the health, wellbeing and job satisfaction of non-resident workers; and to attempt to find a relationship between different accommodation variables and workforce wellbeing and retention. In doing this it investigates evidence for the linkage between accommodation factors, hours of work, health, well-being, job satisfaction and job retention in the LDC work force.

Aug 1, 2013

By K. S. Raja, B. Pesic, S. Kshetri

"We investigated the electrochemical corrosion behavior of commercial permanent magnetic material (NdFeB alloy) in 0.1 M NaH2PO4 solution (pH:4.75) containing 0 – 1000 ppm of chloride at room temperature (298 K). The material was evaluated in magnetized and demagnetized condition with different surface preparations such as: Ni-Cu-Ni coated, uncoated (bare), and anodized (in fluoride containing ethylene glycol at 60 V for 15 minutes to form a thick nanoporous oxide surface). The nickel coated magnetic sample showed reasonable pitting corrosion resistance up to 100 ppm chloride addition. The uncoated samples showed passivity in chloride free phosphate solution. Chloride additions caused pitting and the pitting protection potential was equal to the corrosion potential with 100 ppm chloride addition. Demagnetization did not alter the electrochemical polarization. However, the passive film formed on the magnetic sample showed higher charge carrier density than the film formed on the demagnetized sample. INTRODUCTIONSintered NdFeB permanent magnets exhibit excellent magnetic properties such as large energy product [(BH)max > 450 kJ/m3], high saturation magnetization (1.6 Tesla), and high coercivity (1.2 – 2.08 x 106 A/m) (Sugimoto, 2011). However, the NdFeB magnets are prone to corrosion attack because of the presence of Nd-rich intermetallic phases, such as Nd4Fe (Jurczyk & Jakubowicz, 2000). Nd-rich and B-rich intermetallic phases are distributed in a matrix of Nd2Fe14B tetragonal ferromagnetic compound in a permanent magnet. Generally, several types of Nd-rich phases are present in the magnet with Fe:Nd ratios ranging from 1:1.2 to 1:7. The volume fractions of Nd-rich and B-rich (Nd1+xFe4B4 type) phases are about 10% and 7% respectively (Li, Ma, Li, & Wang, 2011) . Among these intermetallic phases, Nd-rich phase has the most active electrochemical potential. Therefore, dissolution of this phase occurs in preference to other phases by galvanic corrosion when exposed to moisture. Since Nd-rich phases are present at the grain boundaries of the Nd2Fe14B matrix, corrosion leads to disintegration of the magnet."

Jan 1, 2012