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By C M. Zammit, N Cook, F Reith, C L. Ciobanu, J Brugger

The role of biological agents in the gold mining industry is currently limited to the use of microorganisms in bioleaching and bioremediation. However, there is a variety of possibilities in which biotechnology could aid the mining industry in the future. In this article we discuss the potential for the development of these novel biotechnologies and the role they can play in the exploration for new gold deposits, the processing of ores and the post-mining remediation of sites. The development of these biotechnologies has been enabled by rapid advances in our molecular-level understanding of the role microorganisms play in the solubilisation, dispersion and precipitation of gold. An understanding of the distribution of microbial species in soils overlying mineralisation can be utilised to develop bioindicator systems that assist with gold exploration. An in-depth knowledge of how microorganisms interact with gold complexes is being used to develop in-field biosensors, supporting exploration. Processing technologies may be improved based on advances in our understanding of the interactions between microorganisms, ore minerals, cyanide and gold. For instance, cyanide-producing microorganisms are being investigated for use in in situ leaching of gold. In turn, the use of cyanide-utilising microorganisms for the degradation of cyanide is being explored. Combined, the implementation of these biotechnologies in the gold mining sector may revolutionise the industry, leading to greener, more efficient exploration for and extraction of gold.CITATION:Zammit, C M, Cook, N, Ciobanu, C L, Brugger, J and Reith, F, 2013. Possible future applications of biotechnologies in the gold industry - a prospective approach, in Proceedings World Gold 2013 , pp 233-244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Jerry Rowe

There are numerous examples of historic and recent mines that have no closure system or have poorly designed closure systems. These mines may contaminate water resources, land resources and cause significant impacts to human health and the environment. As a result of these problems, many regulatory agencies around the world require that mine closure systems be implemented to manage ARD and protect water resources. In this sense, the paper discusses some of the key elements that need to be evaluated when selecting a mine closure system. These include the specific site climatic, hydrogeologic, hydrologic and geochemical conditions that must be considered for closure design. Two examples of innovative mine closure systems that have been implemented to take advantage of site specific conditions to effectively manage water are provided. The mine closure systems incorporate passive measures to control ARD (acid rock drainage) and protect water resources.

Sep 21, 2013

From a vast army of workers to gargantuan machines to immense volumes of material being moved, almost everything about the Port of Miami Tunnel (POMT) project points to tunneling on a massive scale. Almost.The star of this underground and underwater show is a Herrenknecht tunnel boring machine (TBM,) nicknamed ?Harriet? by a local Girl Scout troop. With her 12.9-m- (42.3-ft-) diameter cutting head and a total length of 139 m (457 ft), Harriet is boring through thousands of cubic meters of clay, dirt and sand, which is often mixed with coral and other materials, to create two 1,280-m (4,200-ft) traf?c tunnels connecting Watson Island and the Port of Miami (Dodge Island) beneath Biscayne Bay, FL. But in the midst of all of the oversized equipment and machines, a strong contender for the best supporting nod goes to a relatively tiny machine: the Brokk 400. Bouygues Civil Works Florida crews are using the compact, remote-controlled and electric-powered machine to excavate five cross passages between the twin traffic tunnels. The pas-sages will be essential to the safety of people who drive their vehicles under the bay every day.

Sep 1, 2013

By Christopher Bambridge

The Washington State Department of Transportation (WSDOT) is constructing a new tunneled route under Seattle to replace the existing State Route 99, Alaskan Way Viaduct (AWV), which follows the historic waterfront for several miles. The viaduct separates the businesses that rely upon the tourist trade from the down-town area. The reconnection of the city to the waterfront areas will occur following the completion of the SR99 Re-placement program that replaces the aging structure that was severely impacted by the 2001 Nisqually earthquake, with a state-of-the-art, twin-deck highway with a world record-breaking 17.4-m (57.3-ft) bored tunnel. Constructed in the 1950s, the double-tiered viaduct is nearly 3.2 km (2 miles) long and runs parallel to city?s waterfront. The viaduct, which is partially supported by the seawall, is a vital local and regional transportation link and carries about 110,000 vehicles each day. The seawall, built from concrete and timber in the 1930s, extends along Seattle?s waterfront and supports the soil behind it. Studies in the 1990s showed that the viaduct was nearing the end of its useful life, apparent by its exposed rebar and weakened columns. The 2001 Nisqually earth-quake further damaged the viaduct, forcing WSDOT to temporarily close it for inspection and limited repairs. The viaduct and nearby seawall are vulnerable to an-other earthquake and continue to show signs of age and deterioration. Following a collaborative process, WSDOT developed the following guiding principles to the viaduct replace-ment:

Sep 1, 2013

By K. Lang

The use of high-efficiency electrical submersible pumps (ESPs) for large scale, open pit mine dewatering operations provides a good example of how technology, products and services from the oil and gas industry can be adapted to the mining industry. In this case, the mine is Goldcorp?s Peñasquito in the Zacatecas state of Mexico, at the Peñasco and Chile Colorado open pit deposits. The technology, products and services are from Schlumberger artificial lift (AL) and Schlumberger industrial water services (IWS). Overview of high-efficiency ESPs This section provides a brief description of the basic components, specifications and operating capacity ranges for the ESPs compared with traditional or conventional dewatering well pumps. This information helps to establish how ESPs provide certain functional and economic advantages over conventional pumps in a mine dewatering application. A schematic of a high-efficiency ESP in an oil and gas (O&G) application is shown in Fig. 1.

Sep 1, 2013

By J. Marts

Underground longwall coal mining sections are operated as sealed gobs if the coal is prone to spontaneous combustion. Sealing along the gate roads during longwall face retreat limits the flow of fresh air (oxygen) into the gob and, thus, deprives the spontaneous combustion reaction of oxygen. In a project sponsored by the National Institute for Occupational Safety and Health (NIOSH), researchers at the Colorado School of Mines have used computational fluid dynamics modeling to simulate the flow of gases in sealed longwall gobs. The models were validated using measurements and observations from the field and demonstrate that targeted injection of nitrogen along the gate roads inby the face can be used to control the size and location of explosive methane clouds within the gob and to minimize or eliminate the explosion hazard resulting from the formation of flammable methane-air mixtures.

Sep 1, 2013

By Emmanuel Pornillos

Dado que en el Perú, la actividad minera utiliza el minado subterráneo para la explotación de minerales, se revalúa el uso de estos en pasta cementada para el relleno de las labores subterráneas, así como los relaves desaguados para su disposición superficial. En ese sentido, el presente texto señala las experiencias de diseño y operacionales de sistemas múltiples para la aplicación de relaves en superficie y subterráneo en el Perú, de forma que se pueda optimizar la selección de equipamiento y una operación robusta.

Sep 1, 2013

By Gregory T. Ziegler

A complex soil profile and high water table, together with a below-grade active subway tunnel, an above-ground elevated railway line, and the heavily travelled Northern Boulevard all passing above the tunnel alignment, combined to make mining of New York?s Northern Boulevard Crossing what is widely considered to be the most challenging portion of the multi-billion-dollar East Side Access project. The Northern Boulevard Crossing is a vital link in this project which, when completed, will connect the Long Island Railroad to Grand Central Terminal in Manhattan. How the sequential excavation method (SEM) tunneling was successfully accomplished, despite the obstacles, was a textbook exercise in practical innovation coupled with close cooperation between the owner, the construction manager, Hatch Mott MacDonald, the designer, Parsons Brinckerhoff, the contractor, Schiavone-Kiewit, and spe-cialty geotechnical contractor, Moretrench.

Sep 1, 2013

By A. B. Cecala

Video technology coupled with datalogging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. these techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties. the Helmet-Cam is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a datalogging dust monitor. these are worn by the miner in a backpack, safety belt or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data filesare downloaded to a computer and then merged together through a NIOSH-developed computer software program called enhanced Video Analysis of Dust exposure (eVADe). by providing synchronized playback of the merged video footage and dust exposure data, the eVADe software allows for the assessment and identificationof key work areas and processes, as well as work tasks that significantlyimpact a worker?s personal respirable dust exposure. the Helmet-Cam technology has been tested at a number of metal/nonmetal mining operations and has proven to be a valuable assessment tool. mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed eVADe software will be available for download at no cost on the NIOSH website.

Sep 1, 2013

By H Park, V Sahajwalla

"Due to the increasing amount of gangues in iron ores, a beneficiation process is required more as a preliminary step for ironmaking process. However, mechanical grinding and washing of iron ore needs tremendous effort that increases operating cost. Therefore, there is a necessity of a novel approach to ironmaking which can tolerate considerable amounts of silica or alumina. In the present study, a high alumina-carbon composite pellet was examined for an ironmaking process. The effect of compositional changes in the CaO-FexOy-Al2O3-SiO2 oxide system on the reduction of carbon composite pellets was investigated in a purpose built thermo-gravimetric analyser (TGA) at 1473K (1200¦C). As a result, alumina increased the reaction rate of carbon composite pellets by increasing surface area, while silica decreased the reaction rate by lowering surface area of samples. Infrared gas analysis assisted with the reaction kinetics of carbon composite pellets through measurement of CO and CO2 in off-gases. This study will assist with establishing the new pelletising method which differs from the conventional fluxed pellets.CITATION:Park, H and Sahajwalla, V, 2013. Effect of CaO-FexOy-Al2O3-SiO2 oxide system on the reduction of carbon composite pellets, in Proceedings Iron Ore 2013, pp 467-472 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

By M Bannear, C Stanton

Since 2008, Arrium has been developing and commissioning a new low-grade hematite ore benefication plant (or OBP) at its Iron Baron mine site.The Iron Baron mine, which was closed in the 1990s, could not consistently yield the high-grade hematite required for pelletising. However, in todayÆs market, the 12 Mt of waste dumps represent a significant low-grade hematite resource, ideal for benefication.Initially, an internal scoping study and several sampling campaigns were conducted to determine the ability to upgrade the available low-grade dump material to a product suitable for export. Test work was conducted at Mineral Technologies (formerly CPG), and included high intensity magnetic separation, spiralling and jigging. Due to promising results from a wet processing circuit, Arrium engaged Mineral Technologies to design a flow sheet that could provide 1 Mt/a of a mixture of high-grade lump (-32 + 8 mm) and fines (-8 mm) products for export.With construction of the plant completed in late January 2012, Arrium, in conjunction with Mineral Technologies, began two commissioning phases. Each phase ended with a toll gate to prove the plantÆs capacity to reach rate and desired grade. After an initial period of running on water, feed solids were introduced to the plant and troubleshooting of bottlenecks began. The first toll gate, whereby the plant was required to run for 24 hours at an average feed rate of 200 t/h (80 per cent of design rate), was completed on the 1 March 2012. Further troubleshooting and resolving of issues allowed the plant to steadily increase feedrate while maintaining good availability and grade. The second toll gate required the plant to run for 72 hours at an average feed rate of 200 t/h while meeting grade, yield and water consumption targets. Sampling campaigns were conducted during this period to track the performance of key equipment. Completion of the test, and full handover of the plant to Arrium, was completed on the 21 April 2012.Although the formal commissioning phases had been completed, ongoing optimisation of the OBP continued, ensuring that all major equipment was working to produce the optimum yield and grade. Sampling campaigns were conducted on the jigs and spirals, with results and correlations used for operations documentation.Overall, with successful completion of the final acceptance tests, the commissioning of the Iron Baron OBP has been established as a major success achieving all production and quality targets as per the original design intent.This paper will focus on the successful commissioning and ramp-up performance of the plant however reference will also be made to the key development stages involved with the development of the project.CITATION:Stanton, C and Bannear, M, 2013. ArriumÆs Iron Baron hematite beneficiation plant - a success from start to finish, in Proceedings Iron Ore 2013 , pp 547-552 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By T Atchison

The Vale Ferro Carajßs S11D project in northern Brazil is based on the movement of unprecedented volumes of waste and ore for mobile in-pit crushing and conveying or ætrucklessÆ systems. In peak years, the system is intended to handle a combined 160 Mt of material.The planning and implementation of the first such system for Vale, in a remote greenfield site, utilising the services of a range of international study, design and supply partners has provided a unique set of technical and project delivery challenges. The lessons from these are of value to the industry as the trend to remote and high-volume operations continues.This paper describes the key features of the mining system and documents the challenges and mitigations for important technical, cultural and project delivery issues that have arisen. It is a combined description of the journey taken by both Vale (as owner) and SKM (as delivery partner) over the course of many years.CITATION:Atchison, T, 2013. Lessons from the S11D truckless mining project, in Proceedings Iron Ore 2013 , pp 177-184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By E Selvapandian, R Barr

Arrium (previously OneSteel) initiated a desktop study into the performance of its hematite ore beneficiation plant in early 2010. The beneficiation plant utilises jig concentrators and spirals to upgrade low-grade hematite recovered during mining at the Iron Duke (ID) mine site located 60 km south-west of Whyalla. The study, conducted in conjunction with Mineral Technologies, identified a number of opportunities for improvement, which were validated by a series of sampling campaigns and a pilot plant trial. One of the major recommendations was to upgrade the ultra-fines processing circuit from a single-stage spiral circuit to a three-stage circuit. The upgrade of the ultra-fines circuit was estimated to provide a significant increase in fines production and grade.In order to capitalise on the strong iron price at the time of the project, Arrium decided to utilise a fast-tracked approach to design, construct and commission the processing equipment required to achieve the improvements identified. This decision introduced the risk of missing critical steps in the project development process, which could have potentially resulted in major issues in latter stages of the project. In addition to the challenges introduced due to the expedited time line for project completion, this project presented unique challenges due to its brownfield nature. One such challenge faced was the integration of the new equipment and control system software.Furthermore, the importance of the ID ore beneficiation plant (OBP) contribution to the companyÆs export commitments meant the upgrade work had to occur while minimising disruption to normal operation. This decision presented a set of new challenges to an already complex project. One such challenge was the need to build and commission the new spiral circuit in isolation from the operating plant.The aim of this paper will be to highlight some of the challenges faced in a complex brownfield project such as the ID OBP upgrade and discuss how they were managed to enable the successful commissioning of the process in early 2012.CITATION:Selvapandian E and Barr, R, 2013. Managing challenges faced in the brownfield commissioning of an ultra-fine hematite processing circuit at ArriumÆs Iron Duke ore beneficiation plant, in Proceedings Iron Ore 2013 , pp 533-538 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By K Knorr, S Birch

The mineralogy of new certified-reference-materials (CRM) for X-ray fluorescence from Western Australia (ASCRM 030 to 035) was analysed by X-ray diffraction using the BRUKER energy dispersive one-dimensional detector LYNXEYE-XE. The samples were studied using standard-less quantitative phase analysis, based on the Rietveld method. This method delivers the relative amount of crystalline phases. All materials were found to be high-grade iron ore predominantly consisting of hematite and goethite and very low amounts of magnetite. In addition, the gangue mineralogy was characterised. It consists of low-per cent amounts of carbonate (siderite/calcite), quartz, kaolinite, chlorite and gibbsite.Furthermore, all samples were analysed with the external standard method. This is an elegant way to probe for amorphous content without adding an internal standard. All six samples were found to contain up to 16 per cent amorphous or nano-crystalline material.CITATION:Knorr, K and Birch, S, 2013. Mineralogy of new Australian x-ray fluorescence standards, in Proceedings Iron Ore 2013 , pp 269-274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By P J. Marsh, P J. Bartsch, N J. Semler

Iron Road Limited is currently studying the feasibility of producing 20 Mt/a of high-grade (67 per cent Fe) magnetite concentrate from a 2.6 Bt resource (JORC) located at Warramboo on the central Eyre Peninsula in South Australia. Bulk concentrate has been tested at a relatively coarse grind size of -106 ¦m. The preliminary flow sheet has been confirmed based on initial mine plans and comprehensive metallurgical testing across the range of mineralisation. Extensive Davis tube testing to predict magnetite recoveries has been conducted over the resource, however this was completed at settings different to the optimised settings developed in the metallurgical test work program.This paper outlines the development of an ore treatment simulation in SysCAD which utilises the mine production plan, the Davis tube test data from the resource, data from metallurgical test work and process design criteria to predict magnetite concentrate deliveries. Mineralogical data, including QEMScan results and metallurgical assessments, were a fundamental basis of the process models which enable predictions of concentrate yield and quality. Power and water requirements are also calculated within the model. SysCAD dynamic simulation has been used to assist with the design of the process plant and downstream infrastructure. The simulation has been set-up to allow iterative integration and optimisation of the mine plan when it becomes available.CITATION:Semler, N J, Marsh, P J and Bartsch, P J, 2013. Iron RoadÆs prediction of magnetite concentrate production from the Central Eyre Iron Project, in Proceedings Iron Ore 2013 , pp 539-546 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By T Krull, T J. Donohue, D Ilic

"Problematic issues in materials handling applications are often amplified in the iron ore industry due to the relatively high density of the ore as well as the abrasive nature of the product. One of the main issues arising from the handling of iron ore is excessive wear, with two applications typically suffering accelerated wear issues being transfer chutes and conveyor belts. These wear issues are problematic due to additional capital costs, but mainly due to the associated downtimes resulting in the accelerated wear. This study will focus on the modelling of iron ore in practical applications where design work was undertaken in order to reduce the wear rates of different materials handling equipment.CITATION:Donohue, T J, Ilic, D and Krull, T, 2013. Modelling of iron ore in materials handling applications with a focus on wear, in Proceedings Iron Ore 2013, pp 355-362 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

By A Wanninayake, E Novello, I Gillani

A residue storage facility (RSF) was designed to cater for Davidson Creek Area and Robertson Range Area operations under the FerrAus Pilbara iron ore development project in the Pilbara Region, Western Australia. Annual ore production was about 15 million tonnes over a period of up to 15 years. The RSF was designed to handle a tailings production rate of 2.2 Mt/a over the project life with ability to be expanded at a later date. The composition of tailings was predominantly -45 ¦ material with some spiral reject material. The fraction of solids was expected to be between 40 per cent and 50 per cent solids by weight.The RSF was designed as an above ground storage facility, integrating with a mine waste dump planned close to the selected RSF site. This integration helped to increase the stability of the RSF embankment and to reduce the construction cost. The main source of construction material for the remaining part of the RSF embankment was selected to be mine waste. The RSF was designed to be constructed in stages by considering the availability of mine waste according to the mining schedule. The use of mine waste for construction of RSF embankments has several benefits over use of borrowed material. These include less construction costs and less disturbances to the environment, by minimising borrowed areas and waste dump footprints.CITATION:Wanninayake, A, Novello, E and Gillani, I, 2013. Effective use of mine waste in the design of a residue storage facility, Pilbara region, Western Australia, in Proceedings Iron Ore 2013 , pp 39-44 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By S Hapugoda, J R. Manuel, M J. Peterson, A Poliakov, E Donskoi

The occurrence and deportment of manganese in a number of ferromanganese and Mn-bearing iron ore samples from supergene-upgraded deposits, as well as from magnetite banded iron formation (BIF) and magnetite skarn deposits, was characterised in order to provide a basis for improved understanding of the processing characteristics of different ore types and investigate the potential for development of a robust geometallurgical classification for Mn-oxide ores. An understanding of the Mn mineralogy in mixed Fe-Mn deposits is necessary to inform any attempt to separate the Fe and Mn during beneficiation and to understand and predict the behaviour of lump and fine ore products during processing.A suite of analytical techniques was utilised, including hand sorting of lump ore particles, optical microscopy, X-ray fluorescence (XRF)/inductively-coupled plasma mass spectrometry (ICP-MS) chemistry, X-ray diffraction (XRD), scanning electron microscopy (SEM)/electron probe microanalysis (EPMA) and gas and solid phase pycnometry, in order to elucidate manganese mineralogy, mineral chemistry and mineral textures. Manganomelane group minerals (eg cryptomelane, hollandite), pyrolusite and lithiophorite were the most common manganese oxides in the samples examined. From the microprobe work, there was evidence of probable substitution of Mn, as well as Al and Si, into the structures of goethite and hematite. Manganomelane minerals were often intimately associated with goethite, in particular, and a clarification of this association and the associated Si and Al impurities is fundamental for improved understanding of beneficiation and sintering behaviour of Mn-oxide ores. Due to the poor or very fine crystallinity of some supergene manganese deposits and of some Mn oxide minerals, in particular the extent of overlapping peaks and their variable mineral chemistry, XRD was a problematic technique to equivocally determine Mn mineralogy.For lower-grade, earthy, poorly microcrystalline ores the mineralogical and textural association between mixed Mn, Fe and Al (¦ Si) phases was also critical. The deportment and potential separation of these elements in these deposits, especially Al, was complex, as they were characterised by forms of æhydrousÆ cryptomelane with higher levels of Fe-Al-Si substitution, as well as intimate intergrowths of ochreous-earthy goethite (probably aluminous in part) with cryptomelane, lithiophorite and/or kaolinite.Trace amounts of alkali elements in ferromanganese deposits were considered likely to be preferentially structurally associated with Mn oxides, while lateritic deposits with significant amounts of lithiophorite could contain elevated levels of deleterious impurities; Co and Ni in particular.A combination of solid and gas phase pycnometry proved to be a useful technique for broadly discriminating hematitic, goethitic and mixed Mn oxide-goethite lump particles based upon differences in their envelope and apparent densities. Based upon these preliminary results and ongoing Raman spectroscopy work on manganese deposits sensu stricto, Raman spectroscopy is a technique considered to have promise during targeted research to better link the optical and compositional properties of ferromanganese ore particles. CT-scan (computed tomography scan) analysis could also be combined with Raman spectroscopy and pycnometry to link mineral composition, mineral texture, ore particle textures and particle porosity/permeability to the high-temperature processing behaviour of lump and fines products.CITATION:Peterson, M J, Hapugoda, S, Manuel, J R, Donskoi, E and Poliakov, A, 2013. Textural characterisation of manganese minerals to improve the geometallurgical characterisation of ferromanganese and iron ores, in Proceedings Iron Ore 2013 , pp 281-300 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By P Hawke, J Hurst, B KrapeP

Hancock Prospecting Pty Ltd (HPPL) drilled two deep diamond stratigraphic holes (ECD0001 and RHD0296) within the eastern Fortescue Valley in the Pilbara of Western Australia. Located south of the Roy Hill Iron Ore project, the holes aimed to define the stratigraphy of the Marra Mamba Iron Formation (MMIF) of the Chichester Range and its south-dipping extensions below recent cover. Previous attempts to define the MMIF of the Chichester Range have resulted in differing interpretations due to the data available at the time.The unweathered MMIF beneath the Fortescue Valley in the HPPL drill holes is characterised by dolomitic carbonate interbedded with stilpnomelane-rich shales, chert and banded iron formation (BIF) with hematite staining. This intersection equates to ~75 m of carbonate-facies iron formation, as opposed to the ~230 m thick oxide-facies BIF and shale sequence encountered south of the Fortescue Valley.Various detailed geological core analyses and interpretations from ECD0001 and RHD0296 were integrated with regional diamond and reverse circulation (RC) holes from across the Fortescue Valley. Interpretation of the data indicates that the eastern Fortescue Valley MMIF represents a thinned thickness sequence of the whole formation. The MMIF of the Chichester Range and Fortescue Valley has gamma logs that correlate strongly in parts to the type section used for MMIF south of the Fortescue Valley. Therefore, the outcropping MMIF in the Chichester Range represents an eroded equivalent of the æreducedÆ thickness MMIF observed in ECD0001 and RHD0296.Data from deep diamond drill holes across the valley, from the Hamersley Basin to the Carawine Basin, were correlated. The correlation shows that the depositional site of the MMIF in the HPPL diamond drill holes is consistent with a proximal ramp setting, in which iron-rich shales wedge up-palaeoslope and shelf-derived carbonate turbidites wedge down-palaeoslope. Not only is it the occurrence of these shales that define the MMIF, but they also determine the northward potential to develop orebodies, as they are the source of iron from which iron-rich oxides and carbonates of metamorphic or diagenetic origin form.CITATION:Hurst, J, KrapeP, B and Hawke, P, 2013. Stratigraphy of the Marra Mamba iron formation within the Chichester Range and its implications for iron ore genesis at Roy Hill - evidence from deep diamond drill holes within the East Fortescue Valley, in Proceedings Iron Ore 2013 , pp 91-106 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By J Visser

Dust mitigation has long been seen as nothing more than managing a nuisance issue, but the reality is that poor dust management can lead to one or more of the following negative consequences: an increased risk of safety incidents, lost revenue, reduced and possibly even lost licence to operate, regulatory intervention, high staff turnover and/or absenteeism and occupational health and safety (OH&S) issues. Dust mitigation and management is not a black art; rather it is a scientifically driven process that can provide an opportunity to increase profits, increase the companyÆs status as an excellent corporate citizen, enhance staff retention and reduce the safety risk profile of the operation.The way to achieve success in dust mitigation and control is to apply the scientific method to each problem that can arise and plague any operation by using current industry best practice. This method of dust problem-solving can be applied to dust issues arising from specific dust sources and locations. The dust sources can include wind impacting on stockpiles, open areas, tailings storage facilities, moving train and truck loads, vehicular traffic on roads, the operation of shovels, front end loaders, draglines and other equipment, as well as ore movement on conveyors.The solutions will come from a combination of deployment of dust collection equipment, dust and moisture monitoring equipment, the appropriate application of water and chemicals, the introduction and maintenance of appropriate barriers and the use of predictive data from local and public weather stations. The paradigm shift required is to view dust mitigation as one aspect of normal operational practice, not a ænice to haveÆ or æunnecessary expenseÆ as most operators currently view it. This attitude is becoming more important as more and more local communities oppose the development of mines. One of the reasons for this local opposition is the inevitable dusty environment that is usually associated with mining.Dust mitigation is not a significant expense if correctly designed and included into the system, either as part of the original design of the operation or as a brownfield installation after the fact. Indeed, there is always a loss of revenue associated with dustiness resulting from ore movement and avoiding this goes a long way to paying for any associated dust mitigating costs.CITATION:Visser, J, 2013. Dust mitigation - changing the paradigm, in Proceedings Iron Ore 2013 , pp 27-38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013