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By J Wheeler

The objective of this paper is to examine the operation of high frequency screens in closed circuit grinding, where the outcomes achieved indicate favourable economic gains at the comminution stage and downstream processes, including flotation, dewatering, and filtration operations. The classification process in grinding circuits has been slowly evolving within the last century. The history of classification devices brings to mind rake classifiers and spiral classifiers, which although having higher efficiencies compared to hydrocyclones, were not able to keep pace with the evolution of concentrator equipment treating higher tonnages. This higher tonnage throughput has tended to drive the concept of utilising hydrocyclones as the classification stage in closed grinding circuits. The comminution process is commonly the most energy intensive stage of mineral processing. Researchers have determined that the classification stage in the comminution process has the greatest potential for improvement. This paper is intended to inform mineral process engineers of the benefits that high frequency screens offer over hydrocyclones. This will be done by reviewing the purpose for the evolution of classification in the comminution process, documenting past and recent studies, and explaining the modern technology that is currently available.

Aug 8, 2011

By M I. Pownceby

High temperature roasting studies on chrome-spinel contaminated ilmenite concentrates showed that sulfur, introduced through a sulfidising roast treatment, selectively reacted with the chromium in the spinels. The roast treatments were carried out in a laboratory scale rotating drum kiln using a standard Becher-style heating profile (10 h, 1075ºC), char as the reductant, and variable amounts of added elemental sulfur (0 - 3 wt per cent).After roasting, bronze-coloured grains were visible representing chrome-spinels that had undergone selective sulfidisation. SEM imaging of the products showed that sulfur was preferentially concentrated in ~5 - 15 µm thick rims fully enclosing the chrome-spinel grains. The sulfur-rich rims became a sink for manganese (Mn) from the ilmenite resulting in the rims being rich in Cr-Mn-Fe-sulfides. Quantitative electron probe microanalysis of phases present within the rims identified two sulfide phases. The first sulfur-phase (S-phase) was low in Mn (1 - 3 wt per cent) and high in Fe, Cr and S, while the second S-phase was considerably higher in Mn (30 - 35 wt per cent Mn) and lower in Fe and Cr. The dramatic change in the composition of the chrome spinels after sulfidisation is likely to significantly alter their physical properties (eg hydrophobicity, conductivity, etc). This should make their physical separation from the ilmenite potentially easier than roasting/magnetic separation methods.

Oct 5, 2011

By G Balog, T Ormerod, D Sidea

Carrapateena is a copper-gold sub level caving operation located in the Gawler Craton, South Australia. One of Australia’s largest undeveloped copper deposits, the project will be a 4.25 Mtpa underground operation, with an estimated mine life of 20 years (OZ Minerals, 2017). First concentrate production was achieved in December 2019, within the Iron Ore Copper Gold (IOCG) hematite breccia complex. The Carrapateena orebody is overlain by 500 m of barren sediments of the Stuart Shelf, which hosts two aquifers. The cover sequence is dominated by shales, quartzites and sandstones in order of thickness. The cover sequence presented challenges to the mine ventilation system as a result of highly variable rock strengths. On this basis, the site developed the first vent rise, Vent Rise 5 (VR5), earlier than required as a means to test the empirical stability assessment. Assessment for VR5 was completed in 2017, with the mine yet to develop through much of the cover sequence. Due to the geotechnical data available at the time, it was anticipated that break out would occur within the vent rise walls as a function of the low strength Woomera shales. VR5 was developed to 4.5 mᴓ in late 2018. The timing of the VR5 development enabled the site technical team to calibrate empirical stability factors for the assessment of future vent rises. At the time of writing, four additional vent rises have been successfully developed to a diameter of 5.5 m. No significant overbreak has been observed within any of the vent rises. This paper is intended for geotechnical practitioners designing large-diameter vent rises in geological environments similar to the Stuart Shelf where a similar approach to vent rise design may be warranted.

Mar 15, 2021

Largely inherited from the past and from strictly internal laboratory use, the certification of reference material using round-robin assaying is often insufficient for the use made today for external assay laboratory control by client parties. Certification often needs to be revisited on the basis of existing round-robin data, especially to derive reproducibility parameters to the end of establishing probabilistic performance gates for operational error detection on a batch per batch basis (ie batch-ærejectionÆ). The most common difficulty arises when only a few certification samples have been analysed in one single batch by each laboratory, so that the round-robin data do not contain the full variability that needs to be quantified. Existing certification data sets from properly submitted round-robin samples were studied using analysis of variance to derive a remedial method, leading to the proposal of default correction factors to restore full variability estimates when no other avenue is available.

Jan 1, 2008

By W Patton, I Minniakhmetov, H Talebi, U Mueller

The sustainability of mining projects is linked to informed investment decisions based on public reporting of exploration and mineral resource estimation results. In Australia, public reporting guidelines are established by the Joint Ore Reserves Committee reporting code through the JORC Code (2012). Although the assessment of uncertainty in the results reported is a requirement, this is often communicated qualitatively and evaluated subjectively. This can become a liability particularly in the early stages of mining projects when spatial domains of geological interpretation and mineralisation envelopes inform resource estimations’ reliability. A recent review of JORC reports found no reports used quantitative assessments of the geological interpretation or mineral resource estimation envelopes, and 27 per cent of reports did not address the question of quality of geological interpretation. Reports that did address the quality used 19 different terms to communicate quality. This work presents methodologies for quantitative uncertainty assessment and communication and explores how they could be applied in public reporting practice. Quantitative uncertainty reporting would benefit mine planning and financial modelling as they normally assume the geology is 100 per cent right (since no error is reported or only a single deterministic model is provided). The complexity, cost, and additional work of doing a quantitative assessment could hinder a straightforward implementation. This could be overcome if mining companies budget for quantitative uncertainty assessment and associated professional development. A compulsory requirement for the inclusion of uncertainty assessments in public reporting or adopting standardised subjective language would improve industry practice.

Mar 22, 2022

By C R. Fountain, R J. Sinclair

The zinc industry is dominated by the electrolytic zinc (EZ) process. The EZ process has a low tolerance for impurities, resulting in tight concentrate specifications. Many mining companies sacrifice zinc recovery in order to meet smelter specifications. Some have ore-bodies that cannot be economically developed because too much metal has to be sacrificed, or it is just not possible to meet the specification. The BUKA Zinc Process (BZP) has been developed as a method of producing high-quality zinc from a wide range of concentrates. It can have lower capital and operating costs than the conventional zinc and lead production routes. Advantages accrue from increases in metal recovery during concentrating, smelting and refining; the elimination of most of the capital and operating costs associated with lead smelting; reduced transport costs; lower zinc refining costs; reduced refinery residue disposal costs; and reduced future environmental liabilities. This paper describes results of testwork that has been undertaken to demonstrate the viability of the BZP on both test rig and laboratory-bench scale.

Jan 1, 1998

By A Valero, G M. Mudd

There is active debate and research around the most suitable indicators to assess the sustainability of mining. The most common approach is to report a range of data for a given mine site (or less preferably, a company total), such as inputs, outputs, benefits and potential costs. The most popular protocol in use (and growing rapidly) is the Global Reporting Initiative (GRI). However, these measures are numerous and still do not allow a single over-arching indicator to be developed. Other measures, such as known mineral resources over time, do not account for critical challenges such as declining ore grades, increasing wastes and poorer quality ores or more difficult mineralogy. By adopting a thermodynamic approach to sustainability, through the concept of æexergyÆ, it is possible to incorporate into a single measure the effective quality of mineral resources. Exergy involves the assessment of the minimum energy costs involved in producing a mineral resource with a specific chemical composition and concentration from common materials in the environment. The exergy of a mineral resource is evaluated from mineralogic composition, concentration (or ore grade) and, of course, quantity, by multiplying the unit exergies with the tonnes of the resource produced (or consumed). Since exergy is a thermodynamic quantity (ie energy or joules), it is additive across different minerals, such as iron ore to gold to copper or even oil and gas or coal û making it an ideal indicator to assess mineral resource sustainability at the industry scale rather than the individual mine scale. This paper briefly outlines the theoretical basis for exergy, and then presents a range of commodity case studies showing the application of exergy to the Australian mining industry. Overall, the usefulness of exergy is clearly demonstrated for use as a broad indicator of the sustainability of mineral resources at the national or even global scale.

Jan 1, 2009

By R Ahola, M D. Henschel, M A. McParland

With the introduction in recent years of third-generation interferometric synthetic aperture radar (InSAR) techniques, monitoring of mine slopes, benches and surrounding areas has benefitted from increased accuracy and coverage. Fundamental research into point and distributed scattering techniques has pushed the use of InSAR to provide higher spatial and height resolution. In this paper we discuss the operationalisation of third-generation InSAR techniques and show its application to active mining operations.This paper will discuss the use of multiple independent measurements of ground movement obtained from operationally-derived InSAR products over a wide variety of deformation areas within an active open pit mining operation (ie pit slopes, dewatering depressions, tailings containment and waste dumps). A technique that shortens the time between observations (increased observation frequency) and provides ongoing estimates of measurement accuracy will be described. The methodology exploits available satellite data by using multiple satellites and multiple beams. The paper will also examine factors in the design of a mine survey with third-generation InSAR and illustrate some of the necessary engineering trade-offs to efficiently monitor a mine from space.Overall, this paper aims to demonstrate the capabilities and advantages of operational third-generation InSAR techniques for ground movement monitoring of mining operations and provide a framework for proper design of a mine InSAR survey.CITATION:Henschel, M D, Sato, S, Ahola, R and McParland, M A, 2014. Designing interferometric synthetic aperture radar surveys for mine monitoring with accuracy assessment, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 233–238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By T G. Vizcarra, T J. Napier-Munn, A T. Karbowiak, M G. Hart

Squeezing extra performance from existing equipment (‘sweating the assets’) is key to continuous improvement initiatives, particularly during times of cost cutting where the option of spending additional capital to facilitate circuit upgrades can be severely constrained. A common challenge, however, is identifying the best combination of settings for different process variables, as their effects can be camouflaged by interactions with other process variables and, of course, noise in historical data.This paper describes a recent investigation at Boyne Smelters Limited to identify strategies to coarsen the product of its dry, fixed-speed, open-circuit AG mill, without the need for installing pre-screens prior to the mill. The product is used as insulation material for the reduction of alumina to aluminium, and an excessively fine product was inhibiting the ability of the cover material to dissipate heat from the underlying anodes. The approach was to undertake a series of experiments, designed according to statistical criteria, to elucidate the effect of key process variables (feed blend and power draw) upon the product sizing. The results provided clarity about what strategies would encourage the production of a more desirable mill product (with some surprises). The study is a good example of how properly designed experiments can identify hidden potential in processing circuits, thereby mitigating the need for capital-intensive upgrades.CITATION:Vizcarra, T G, Hart, M G, Karbowiak, A T and Napier-Munn, T J, 2018. Getting the most from existing processes: using cleverly designed experiments to optimise the line 3 AG mill at Boyne Smelters Limited, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 207–216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

Hydraulic backfill is generally retained in slopes using permeable barricades. Mitchell et a! (1975), Mitchell (1992) and Grice (1989) have shown that under normal drainage conditions, barricades experience low levels of loading. Cowling et a! (1988) have also shown that barricades are susceptible to piping failures if excess water has ponded on the upper backfill surface and if leakage of backfill from the barricades has occurred. During 1997, six hydraulic backfill barricades failed in four different Australian mines. Fortunately, in each case, the quantity of backfill slurry released was small, and no injuries to personnel nor damage occurred. Detailed investigation of two of the incidents showed that the primary cause of failure could be attributed to the delivery of excess quantities of transport water from the low-density slurry. For each of the incidents investigated there was evidence of the development of piping failures, which resulted in hydrostatic loading conditions on the barricades from the ponded water on the upper backfill surface. The circular failure surfaces in the barricades were characteristic of the application of point loading Conditions.

Jan 1, 1998

By B L. Coulter, E Wightman, A S. Burrows

With their commitment to sustainable development in an increasingly carbon-constrained world, many resources companies are focused on reducing the energy required to create their final products. In particular, the comminution and smelting of metal-bearing ores are both highly energy-intensive processes. If resource companies can optimise the energy efficiency across these two processing stages, they can directly reduce their overall energy consumption per unit mass of metal produced and thus reduce their greenhouse gas footprint. Traditional grinding and flotation models seek to improve the efficiency of mineral processing, but they do not consider the energy used by downstream metal production, eg smelting and refining. Concentrators and smelters individually may be running efficiently, but are they optimising energy consumption of the overall system? A key step towards answering this question is to understand whether it takes less energy to remove an impurity in the concentrator or the smelter. Analysis of the complete concentrator û smelter process chain may show that there are times when the concentrator should use more energy to reduce the overall energy requirements across the mill and smelter. The new methodology discussed here will integrate downstream processing energy with mineral processing energy, to find the overall most energy efficient circuit design and operating strategy. The proposed methodology includes: determining what grade and recovery positions can be achieved in the concentrator by using different combinations and amounts of grinding and regrinding, thermodynamic calculations of the energy used to process the different concentrate grades to metal, and integrating the concentrating and smelting models to find the lowest total energy for the system. A case study which investigates the effect of increasing regrinding energy on the overall mineral processing û smelting energy consumption is presented. For the copper-nickel sulfide ore investigated the addition of regrinding results in 11 per cent less energy being used in the overall concentrator û smelter process chain per tonne of metal produced. Although regrinding is often seen as an energy-intensive process, in this case study the use of 1 kWh of energy for regrinding reduces the overall energy consumption by 12 kWh. The new mill to melt methodology will allow companies to model energy consumption from mill to smelter with a view to reducing the energy-intensity and greenhouse gas footprint of their processing and smelting operations.

Jan 1, 2009

By B C. Povey, K Lagutin, M Mryasov, V Noll

The current Stoilensky magnetite concentrator comprises a three-stage crushing circuit followed by three stages of ball milling, grinding and concentration to produce a magnetite concentrate with 66.5% iron (Fe). The plant is built in four lines, three lines having four mills and one line with five mills, to treat 32 Mt/y of ore and produce 13.9 Mt/y of concentrate.NLMK, the owner, is Russia’s third largest steel maker and while the ore from the Stoilensky Mining and Beneficiation Plant (SGOK) provides the bulk of their supply, they still must buy ore from external sources at world prices. A decision was taken to expand the SGOK operation to supply all the NLMK concentrate, including the production of pellets.To commence the expansion, high pressure grinding rolls (HPGRs) were introduced as a fourth stage of crushing ahead of the first ball mill. This was a relatively low capital cost expansion and increased production by 12 to 15%, the cost being much less than an additional grinding line. The importance of this development was that earlier introductions of HPGRs in Russia had presented several problems so there was some reluctance to the initial concept. The even greater significance was that nearly every magnetite plant in Russia had a three-stage crushing circuit so the successful introduction of HPGRs was of interest to many operators.The design was developed by a team, consisting of Worley Parson, Mineralconsult and PiterGORproject (PGP), for the first four units to fit inside existing building structures. The first two units were commissioned in March 2016 and the next two units in May 2016, and production improved by over 12%. The design of the installation of the final four units is in progress and the installation is expected in late 2017.CITATION:Povey, B C, Noll, V, Lagutin, K and Mryasov, M, 2017. Introducing HPGR quaternary crushers in a Russian magnetite operation – challenges and solutions, in Proceedings MetPlant 2017, pp 84–100 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By J Heyes, R Getty, M Sanapala

Closure is an inevitable part of the life cycle of every mine. Successful closure outcomes critically depend upon early and ongoing integration of closure planning and mine planning. Early and holistic integration minimises residual risk and maximises opportunity to leave a cost-effective, positive legacy for the company, investors and future land users. Both disciplines are inherently interconnected and aim to maximise ‘value’ via trade-offs. Historically, integration of closure into mine plans has been poorly implemented across the industry. There is still a perception that closure planning only starts as the end of a mine life approaches. This inevitably leads to tension when making business decisions, with progressive closure often being deferred due to short-term drivers and incentives. To create a positive legacy after production has ceased, this tension can be managed by transparently and fully informing business decision-makers, such that the impacts of short-term decisions on long-term closure objectives are understood. BHP recently updated a business-wide standard ‘Our Requirements for Closure and Legacy Management’ designed to strengthen collaboration, education and integration of closure across the entire life cycle of the asset. Concurrently, the ‘Life of Asset’ definition was refined to include the postproduction phase, until closure objectives have been met. This paper discusses the criticality of mine planning integration with closure and how updates to Our Requirements sharpen the focus from transactional to transformational planning. These concepts are applicable to any mining operation aiming to achieve successful closure across the full asset life cycle, from exploration to post-production.

Sep 18, 2023

The appraisal of mineral reserves by a lender is carried out at the initial stages in developing a loan for a mine. The depth of investigations is influenced by the competence of the explorer, the type of commodity and knowledge of the geological environment. The lender looks for a reserve life which exceeds the term of the loan plus contingencies for events such as cost over-runs, adverse markets and production difficulties. The physical features of importance are discussed. Factors with direct financial implications are considered for their incorp- oration in sensitivity analyses to allow risk appraisal. When satisfied, the lender can then proceed to review cash flow forecasts, the basic strength of the project, then determine with the borrower the components and alternat- ives of a loan package.

Jan 1, 1979

By Wyborn L. A I, Idnurm M, Hinman M. C

Comparison of the Proterozoic Apparent Polar Wander Path (APWP) for Australia with the corresponding geology of northern Australia suggests that a number of discrete interplate tectonic events, manifested on the APWP as bends or inflections, may have controlled sedimentary basin evolution, ore fluid production and the timing of mineralisation. Similar features in the Phanerozoic APWP for the North American plate appear to correlate with major orogenic events, basin deformation, movement and 'entrapment' of hydrocarbons and minerals. Interplate tectonic events cause intraplate deformation which in turn controls the subsidence/uplift and sedimentation histories of the basins. Interplate events are thus responsible for creating, deforming and destroying sedimentary basins and the associated petroleum and mineral systems. The basins of northern Australia show remarkable similarities in the successions of volcanic and sedimentary deposits. Unconforrnities of regional or sometimes only local extent have been mapped between the major sedimentary sequences and it is predicted that interplate tectonic events corresponding to bends or inflections on the APWP directly reflect the processes that have produced these widespread unconformities. These processes are also likely to have controlled the geometry and character of the fluid migration pathways and hence the mineralising events. Palaeomagnetic studies of Proterozoic rocks in sedimentary basins provide a tool for predicting the timing of regional mineralisation events, particularly for low-temperature mineral systems. The techniques, when coupled with systematic regional basin analysis, using petroleum exploration techniques, may identify a number of new mineral 'plays' in northern Australia. Prominent inflections in the APWP occur at approximately 1700, 1670, 1650, 1600, 1540, and 1480 Ma. Each of these may be related to a regional compressional deformation, important mineralising event, or significant change in style and type of sedimentation. Most appear to be associated with magnetic overprints. Some of the inflections between 1400 and 540 Ma may also mark significant events in the evolution of Meso- and Neoproterozoic basins. Further work is required to correlate inflections in the APWP with alteration events in order to understand their regional significance.

Jan 1, 1994

By D A. Deglon

Solids suspension is important in the design and operation of mechanical flotation cells, and is a necessary precondition to particle collection. Most of the fundamental hydrodynamic research that incorporates some aspect of solids suspension was done by Arbiter, Harris, and co-workers, or Schubert and co-workers. However, a need for research into solids suspension in mechanical flotation cells exists, since very little has been done since the late 1980s; a time that also coincides with the advent of round mechanical flotation cells and the subsequent dramatic increases in maximum flotation cell sizes. In this work, concentration profiles and critical impeller speeds, Njs, were measured in a 0.124 m3, round cell fitted with a 0.150 m, Bateman impeller mechanism. Two solids size fractions (75 - 106 and 150 - 250 ¦m) were tested, in ungassed and gassed conditions (JG = 0, 1 cm/s) and at various impeller speeds (300 - 900 rpm). The effectiveness of solids suspension was quantified in three ways in terms of extent of off-bottom solids suspension, suspension height (extent of solids distribution), and variation within the solids distribution, which together present a complete quantitative picture of solids suspension and distribution within the cell. Consistent trends were found when these effectiveness criteria were considered against relative impeller speed, in terms of percentage of critical impeller speed, N/Njs. Off-bottom solids suspension is complete at or above 100 per cent of Njs, with significant sedimentation occurring as the impeller speed drops below 60 per cent of Njs. Suspension heights consistently reached a level equivalent to 90 per cent of the tank diameter at the critical impeller speed, and dropped off significantly as N/Njs dropped below 60 per cent. The variation in the solids concentrations within the sampled profiles showed consistent trends in two-phase but not under three-phase conditions. The paper concludes that the critical impeller speed, Njs, commonly used in the design and operation of standard stirred tanks, is a very useful solids suspension benchmark for describing all aspects of solids suspension in mechanical flotation cells and should be correlated to system conditions.

Jan 1, 2005

By L Klemettinen, J Biswas, W Malan, D Sukhomlinov, D Lindberg

In order to mitigate the effects of climate change, our society must be able to drastically reduce its CO2 emissions. As the metallurgical industry is a considerable contributor to these emissions, new greener technologies must be invented and developed. One option could be the direct production of metals from oxides using renewable electricity. The aim of this study was to investigate the possibility of using high-temperature molten oxide electrolysis (MOE) for iron and ferrochrome production. FactSage™, ver 8.2 (by Thermfact Ltd and GTT-Technologies) was utilised for estimating a feasible equilibrium electrolyte composition, and the experiments were conducted at 1550–1580°C in conical alumina crucibles with iridium wire as the cathode and platinum wire as the anode. The sources of iron and chromium were either pure FeO powder or industrial chromite pellets. Voltage was applied to the electrolysis cell for 6 hrs and the resulting current was measured, along with oxygen concentration in the off-gas line. The electrolyte comprised of SiO2, Al2O3, MgO and CaO. First, the effect of FeO concentration on iron reduction efficiency was investigated using only pure oxide powders as starting materials. The results indicated that 10 wt per cent FeO mixed with the electrolyte resulted in more efficient iron reduction compared to 20 wt per cent. In further experiments, industrial chromite pellets were ground and mixed with the CaO-free electrolyte. Iron and chromium reduction efficiencies were higher when approximately 19 wt per cent of the total sample mass consisted of pellets compared to increasing the pellet amount to 37 wt per cent. Generally, the chromium solubility in the liquid electrolyte was relatively low, and most of the chromium was confined to the spinel solid solution, from where its dissolution to the liquid electrolyte was very slow, resulting in slow reduction kinetics. For larger scale applications, economically more viable electrode materials should be investigated.

Jun 19, 2024

The sulphide ore occurring in the North Mine at Broken Hill is of a complex nature, consisting of an intimate mixture of argentiferous galena, marmatite (zinc-iron sulphide), and gangue minerals. A typical analysis of the ore is:Lead 15.2%Zinc 12.0%Iron 5.3%Manganese 0.8%Copper 0.1%Alumina 0.3%Lime 0.9%Sulphur 11.1%Insoluble 53.8%Carbon dioxide 0.3%Undetermined 0.2%Silver 9 oz. per tonTotal 100.0%The metallurgical practice for the recovery of the lead concentrate and zinc concentrate from the crude ore is briefly described in the following pages.(1) COARSE CRUSHING AND FINE GRINDING OF THE CRUDE OREThe crude ore from the mine, containing lumps to the size of, roughly, 10 in. x 8 in., is tipped over grizzlies with the bars spaced 3 in. apart; the oversize gravitating to a...

Jan 1, 1933

This presentation is a 20 minute snippet of my professional career, and my progression in the mining industry, from a lazy uni student to an up-and-coming blast engineer in the middle of a mining boom.My name is Daniel Hepburn and I am a blasting engineer for Orica Mining Services. I graduated from Royal Melbourne Institute of Technology (RMIT), in Melbourne in 2003. I completed both of my final year projects with Orica Quarry Services and was offered an assistant shotfiring job, which I accepted and worked for eight months. Having missed the cut-off date for the Orica graduate program, I planned to work with Quarry Services until the following year where I hoped my marks and the experiences I had gained would secure a graduate position. I didnÆt have to wait long, as in August of that year, I was offered (and I accepted) a graduate position in Perth as a technical services engineer for Orica Mining Services. The Orica graduate program is based over two years, and consists of real roles from day one; however, there is also opportunity to fast track the program for high performers. There is a structured rotation, from site to site, interstate or even international if you are so inclined. This includes the backpacker program, which allows graduates to experience the Orica culture in countries of their choice. There are also opportunities to try cross-functional roles in the different Market segments within Orica. I was lucky in that I knew what I wanted to do and where I wanted to work, so I stayed in Perth for my entire graduate program. I was also lucky enough to be fast tracked and finished my graduate program in 15 months. At the end of 2005 I accepted a position as an open cut blasting engineer based in Perth and even in such a short period of time I have already completed a number of major accomplishments. Some of these accomplishments are described below. This paper is available as a PowerPoint presentation only.

Jan 1, 2006

By T Clemens, D Trumm

Adopting environmentally acceptable practices in New Zealand is a crucial requirement for mineral wealth development. Recent planned expansions in the coal and gold industry have increasingly placed mining in the media spotlight. A lack of appropriate standard environmental guidelines has resulted in inconsistent responses and assessments of current and proposed mines. These inconsistencies have lead to delays in decisions on developing economic mineral deposits that may have only minor short-term impacts, and have also allowed unacceptable environmental management practices to continue elsewhere. A research collaboration between CRL Energy, Landcare Research, University of Canterbury and University of Otago aims to provide regulator groups and the mining industry with a unified approach to the requirements of the Resource Management Act 1991,the legislation that largely drives the nationÆs environmental policies and guidelines. The tangible outcome of this research program will be water quality and impact management guidelines integrated into a decision-making framework. The result of this unification will assist in the development of viable mineral deposits and minimise environmental impacts. The framework will be derived from a synthesis of three objectives. Objective 1 identifies potential water quality impact. This objective is based on a targeted geochemical study of the lithology and waterways of the West Coast and Southland regions. Objective 2 categorises the degree of impacts on the ecology of receiving aquatic ecosystems and determines the processes that drive aquatic ecosystem recovery. Objective 3 identifies best strategies to sufficiently manage impacted ecosystems, and to prevent future unacceptable impacts. Wide consultation with representatives of the mining industry and regulator groups will occur frequently during the development stages of the framework. It is anticipated that this multidisciplinary approach will provide a robust and coherent, standardised system that will assist in achieving industry and environmental targets.

Jan 1, 2004