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In November 1986 the Australian Minerals and Energy Council (AMEC) endorsed an "Australian Code for Reporting Identified Coal Resources and Reserves" for use by the Federal and all State Governments. Before this endorsement there were six different coal codes in use in Australia. The code is broad in nature to accommodate the wide range of coal deposits in terms of rank, quality and geological environment, that are present in Australia. In the code, Resources refer to all of the coal in situ which may have potential for use and the various categories indicate the level of confidence of the assessment. Reserves are those Resources which are planned to be mined and for which such planning has been undertaken. Only minimum guidelines are set by the code and the onus is on the estimator to state clearly the criteria used in any Assessment.

Jan 1, 1987

By A Turner, P Hills, D Johnson

Underground mining for gold began in Beaconsfield in 1877 and development of the Tasmania Mine saw the sinking of multiple shafts, including the Hart Shaft over the ensuing 35 years. The mine closed in 1914 at a depth of 455 m due to prevailing economics, eventually reopening in 1999. The modern mine closed in 2012 after extending the mine from a historical depth of 455 m to the exhaustion of the modern Ore Reserve at a depth of 1210 m. West Tamar Council took over the lease for the immediate area around the Hart Shaft as an extension of the adjacent museum. The Hart Shaft and above ground structures became a significant drawcard for visitors. Tasmania was affected by sustained wet weather during May, June and July of 2016 which caused severe flooding and significant Statewide damage. This uncharacteristically intense wet weather caused saturation of the ground surrounding the Hart Shaft. Eventual shaft failure was first identified in August 2016. The failure of the shaft occurred at approximately 50 m below surface and resulted in a plug of material completely blocking the shaft. Significant surface subsidence affecting the surface infrastructure ensued. Due to the unstable nature of the surrounding material, it was determined that addressing the failure above the blockage would not provide a permanent solution to prevent the continued flow of material into the shaft. Many options to stabilise the shaft were considered, however it was assessed that a concrete plug in the shaft in competent ground at a depth of 100 m below surface and well below the blockage, would provide the only long-term solution. Man-entry was considered unsafe. The solution to access ultimately entailed filling the entire shaft with granular fill up to 100 m depth to act as formwork for a concrete plug. The rising mains at 400 mm and 250 mm diameter, which remained in place in the shaft, provided the avenue for placing the fill and ultimately, the concrete plug. Once the plug was in place the remainder of the shaft up to the underside of the blockage and over the top of the blockage to the surface was successfully filled with a combination of more granular fill and flowable cement stabilised sand. The Hart Shaft and surrounding above ground infrastructure was successfully stabilised and re-opened to tourist access. CITATION:Johnson, D, Turner, A and Hills, P, 2018. Stabilising and filling the Beaconsfield Hart Shaft, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 42–57 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By N McKay, J Vann, W Ware, P Hodkiewicz, C Morley

"Geometallurgy is now recognised within the mining industry as an approach that can both maximise value and reduce the risks associated with resource development. The process of spatial ore variability testing for metallurgical response and the use of quick, inexpensive metallurgical proxies has been well developed in the past decade in industry and the literature, and via various collaborative research programs and laboratories. Technology continues to advance with new techniques such as hand-held analytical tools and automated hyperspectral core scanning, allowing for even faster, less expensive in situ geometallurgical testing.In the current mining industry downturn, a critical frontier of geometallurgy is in its application in short-term geological modelling (ore control) and mine planning, and the associated decision-making. This is the end game at which the hard-won knowledge of orebody variability can be exploited to add near-term value. In order for spatial block models to be fit-for-purpose for such tactical uses, they must be populated with key geometallurgical information and then have workflows that use this richer model as a basis of material allocation to destinations so that the true value of the resource is realised.We envision geometallurgy (geomet) programs designed to add and sustain value at two levels:‘Strategic geomet’ has a long-term strategic focus that actively uses all relevant data that helps predict processing performance such as bench-scale metallurgical tests, mineralogy, geochemistry, ore texture etc (‘the geometallurgical database’) to model spatial ore variability and metallurgical response throughout the life-of-mine (LOM). This will enable better resource definition, more optimal mine planning and scheduling, improved process design and sustaining capital strategy over the LOM. The value-realisation is gained by basing all these strategic decisions on spatial models that better reflect the actual value of blocks (or aggregates of blocks) in the model.‘Tactical geomet’ has a short- to medium-term tactical focus that, again, actively uses the geometallurgical database, but also includes new data derived during ore control activities (such as drilling and sampling) to inform allocation-to-destination decisions via the ore control process. This will enable improved efficiency (ie less error) in allocation of mining blocks as direct feed, stockpile or waste. Importantly, this efficiency will be measured in terms of value and not grade, which is an incomplete – and typically biased – proxy for value. The key benefit is that ore control will then be planned and executed on the basis of realised value.We therefore propose a twofold systematic and holistic, value-based geometallurgical process. This process needs to be planned and implemented in an integrated manner, noting that strategic and tactical geometallurgy can be worked on by the same professionals, sharing data, methodologies and potentially models. What differs between the two levels is the required granularity, the business context and (critically) the decision-making time horizons.CITATION:McKay, N, Vann, J, Ware, W, Morley, C, Hodkiewicz, P, 2016. Strategic and Tactical Geometallurgy – a Systematic Process to Add and Sustain Resource Value, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 29–36 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

Crushing Plant Process Optimisation Design of processes in order to find the most efficient solution to a specific task is a difficult problem. Often the number of solutions are large and the optimal solution is therefore difficult to identify. Crushing plant process design is no exception from this statement. In order to find the best solution issues like equipment selection and process configuration must be mastered. The solution must both be technically feasible and preferably have a low operating cost. Since crushing plant design is a complex task with a large solution space it is basically impossible to master without a specialised tool. For a long time simulation softwares have been used to assist in the design process. These tools only give answers for how a user defined plant will operate. There are no tools with capabilities to consider different design options in order to determine what the most efficient solution looks like. In this paper a method for crushing plant design optimisation is presented. The novel method utilises a combined optimisation routine and expert system in order to find the most cost efficient solution to a given process task. The user will only need to define the feed material properties, the process capacity, and the end product requirements. The developed system will find the solution lowest production cost per ton.

Sep 13, 2010

Mine pit slopes in the Pacific Rim are a geotechnical challenge because of the complex geology in which they are developed. Mines are currently being fast-tracked to meet the increase in commodity prices, often resulting in some reduction in ground studies and short-cutting of design procedures. In addition, the resources boom means that skilled personnel are in relatively short supply. At a time when mine pits are getting bigger and deeper, and the engineering is getting more demanding, there is an increased demand on managers to effectively implement the work.   Experience both in New Zealand and the Philippines, display the complex range of geological environments in which pits are being excavated. Working in these conditions has shown that successful geotechnical design requires a strong geotechnical model based on sound geology. An appropriate level of investigation and analyses results in a certain level of understanding for the mine design. There is a point where additional expenditure (on investigation and analyses) is not warranted based on the expected minimal impact on decreasing the level of perceived risk on the project. For most projects in our experience the analytical methods and complexity of geotechnical assessment changes increases as the level of knowledge grows.

Jan 1, 2006

Incidental to the progress of a geological survey of the Kalgoorlie goldfield during 1927 - 1928 a number of specimens of telluride minerals were obtained, chiefly with the help of Mr F G Brinsden, general manager of the South Kalgoorlie mine, and Mr Ernest Williams, general manager of the Boulder Perseverance mine. This collection was supplemented by a number of small specimens, including the rare copper telluride, which were collected and preserved from the Kalgoorlie mine by Mr A E Paton, and also by a few miscellaneous specimens from the collection of MrS F C Cook, of the Palace Hotel, Kalgoorlie.An extensive knowledge of the rare tellurium-bearing minerals was compiled during the last century from occurrences in Transylvania and Colorado. The recognition of different species has been based on chemical analyses and crystallographic measurements. In a few species there has been an absence of crystalline form, and these, together with the discoveries in this century of rickardite and 'weissite', muthmannite and empressite, have depended chiefly on the chemical analysis for identification. On the other hand, the crystalline form of nagyagite and stiitzite has been described in detail, while their precise chemical formulae were doubtfully defined.The announcement of the occurrence of tellurides at Kalgoorlie by A G Holroyd in the Kalgoorlie Mine on 29 May 1896, followed by their discovery in comparative abundance, stimulated the further study of these minerals. In this locality there is a general absence of well-formed crystals, and the knowledge gained has been confined to the record and description of previously known, but exceedingly rare, species.No new species has been recorded, but the intimate association of various species resulted in early description of two supposedly new species, kalgoorlite and coolgardite. These have been discredited since the investigation by L J Spencer in 1903, based on a collection of specimens donated to the British Museum.Spencer's list of species at Kalgoorlie comprises calaverite, sylvanite (or krennnerite), petzite, coloradoite, 'and altaite, and does not include hessite, previously mentioned by Krusch. In 1912 melonite and a copper telluride were added by J A Thomson and the presence of hessite confirmed. In 1912 there also appeared a full and detailed account by E S Simpson on behalf of the WA Geological Survey, which embraced his earlier notes on the tellurides, and which represents the state of our knowledge of the Kalgoorlie minerals, practically as far as can be attained without the use of the reflecting microscope.The position has been stationary for about 18 years, and it was thought. that the best use to which the present collection of tellurides could be devoted was an attempt by mineragraphic methods to study the mineral relationships, not only of the tellurides among themselves, but also to gold and other associated minerals. The precise mineral content and relationships become a factor of added importance with the development of flotation methods of treatment at Kalgoorlie.Moreover, the study would supplement the description of the ore deposits of the Boulder Belt that has recently been published.

Jan 1, 1994

When I was first asked to give a paper on work-life balance in the mining industry I was both excited and aware of the incongruity of my position. I have never worked in mining operations nor have I had any experience that approximates the on-site lifestyle. IÆm not really an adventurer or a traveller, I prefer writing and research to hands-on activities and IÆve never worked further than twenty minutes away from home. The perspective I offer is thus largely an objective one. I say largely since I grew up in a family where my parents work arrangements involved long-distance commuting; my dad continues to work FIFO at a coalmine in Blackwater until this day. Perhaps my tortoise-like existence is a rebellion against his flighty movements. The analysis I will be presenting today draws together a variety of sources, from member anecdotes and research on FIFO and work-life balance to the popular philosophy writings of a bald Englishman with a French name. I am speaking of the famous writer, Alain de Botton, whose television show æThe Consolations of PhilosophyÆ you may have seen on the ABC. Work-life balance is a term that gets a lot of mileage in corporate brochures and at breakfast seminars. But like many terms that get bandied around in the human resources circuit, from æteam synergyÆ to æperformance optimisationÆ, I am frequently perplexed as to what it actually means. Corporate websites are at pains to emphasise the high priority that they place on the needs of the whole person. Yet in terms of substantive content, a commitment to work-life balance often seems to translate into little more than the option to take a few morning yoga classes in exchange for working a seventy-hour week. As extended work hours have taken their toll, leading to high attrition of professionals across all industries, employers are increasingly expending resources to discover just what lies behind this buzz word. The challenge for companies is to find meaningful strategies to help employees better integrate different aspects of their lives in a new era of work, as employees are sending the message that they are not willing to play work, social life and leisure off against each other in a zero sum game.

Jan 1, 2005

By T J. V Duffy, L H. D Siahaan, P G. Albert

G-ResourcesÆ Martabe Mine in North Sumatra, Indonesia, is a US$700 M world-class and world-scale operation in a country which, with a few notable smaller scale exceptions, has had no significant hard rock mining development in more than ten years.The mine was commissioned in the middle part of 2012 and poured first gold on 24 July. At full production Martabe will produce 250 000 oz/a of gold and 2 - 3 Moz/a of silver at cash costs in the lowest quartile. The mine location is on the west coast of North Sumatra, which experiences annual rainfall of 4 m with no notable dry season, adjacent to seismically active fault zones, and relatively close to a rural community of 31 000 people with no significant industrial experience.The management team has successfully forged strong links with the various government departments and levels in Jakarta, North Sumatra Province and the local Regencies; developed long-term relationships with the various community groups within the local district of Batangtoru to build a sustainable social licence; has dealt with the physical and environmental challenges presented by the project location, and has successfully raised more than US$900 M over a period of three years for the original acquisition then the development of the project.Whilst in its infancy of operation, the mine is set up to deliver a long-term sustainable future for the company, the shareholders, and the people of Batangtoru and all stakeholders generally. The quality of the project execution and commitment by the company will ensure that maximum value can be delivered from Martabe, not just for the current mine life but from the significant exploration potential that exists on the large tenement area that the company has access to for 30 plus years.This paper will deal with the physical challenges associated with the design, the Indonesian government regulatory requirements for mine development, the social aspects of building a world-class project in a developing area, the in-country commitment necessary for any project development anywhere in the world and the successful funding arrangements for the mine development.CITATION:Albert, P G, Siahaan, L H D and Duffy, T J V, 2012. Building AsiaÆs latest hard rock mine, in Proceedings International Mine Management 2012, pp 189-204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By S Kost, R Nievergelt, F Cortes

In recent years, the use of steel fibre-reinforced concrete (SFRC) for segmental tunnel linings has become increasingly popular due to numerous advantages including durability, resistance to spalling, reduced cracking at corners and edges and significant cost-saving potential. One of the key parameters for measuring the performance of SFRC is the residual (post crack) flexural strength. A problem often faced in design and quality control of SFRC is the high variability of results obtained by standard beam test methods, with reported coefficients of variability (CoV) in the order of 25 per cent. The high test variability results in a relatively low permissible design strength relative to the average flexural strength of the material and commonly leads to non-conformances with respect to residual flexural strength during production testing.This paper presents the implementation of an alternative testing method using large round determinate panels (RDPs) for quality control testing of the SFRC used in the segmental lining of the City East Cable Tunnel (CECT) in Sydney. The alternative RDP test method was found to correlate well with standard beam tests and significantly reduce the variability of test results, minimising the risk of outlying residual flexural strength results, with zero non-compliant test results reported during the production period.This successful implementation of an alternative test for post-crack flexural strength with lower variability in results constitutes a relevant precedent to demonstrate the feasibility of this approach which contributes to the development of more cost-effective concrete mixes and minimises the risk for non-compliant results and the contractual disputes that commonly arise from these.CITATION:Cortes, F, Nievergelt, R and Kost, S, 2014. Development of a segmental lining specification for steel fibre reinforced concrete flexural strength testing using round panel tests, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 461–468 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Successful evaluation and exploitation of resources and reserves relies on the collection of high quality sample data. The quality of the sample data must be maintained through the application of a robust quality assurance and quality control (QAQC) program, including documentation of sampling procedures, training of sampling personnel and the regular monitoring of control samples. However, the application of QAQC programs in the minerals industry is often poor and the purpose misunderstood. It is all too common to have good quality control data collected, but no analysis work carried out until after drilling is completed. In a lengthy drill program, this can lead to problems not being discovered and corrected as they happen. Moreover, rectifying problems afterwards will be costly in terms of time and money, if not impossible. The consequences of poor quality sample data are many and include such effects as over- or underestimation of block grades, misclassification of ore and waste, and lower confidence in the resource/reserve models. The purpose of this paper is to highlight, using case studies, the importance of good QAQC practices to monitor the quality of sampling and laboratory sample preparation and analysis.

Mar 1, 2010

The JORC Code contains a mandatory classification system for Mineral Resource and Ore Reserve estimates for public reporting. The classification is a statement of the Competent PersonÆs confidence in the estimate and an attempt to convey that confidence to the various users of the resource estimate. In general the classification process is either largely subjective, relying on the Competent PersonÆs experience, or relies on statistical measures derived from the estimation process, or is derived from an estimated level of confidence in the outcome. However, the statistical measures may not necessarily relate to the overall confidence in the resource or reserve which must take account of the confidence in the geological inputs to the estimation.In addition to the traditional deterministic interpretation and estimations adopted by geologists, semi-quantitative techniques are now available to improve the estimation of confidence while continuing to involve the Competent PersonÆs experience in the process. Methods for quantifying confidence in mineral resource estimates for advanced projects and operating mines have also been developed.Classification is undertaken primarily as a communication tool between the estimators and the other stakeholders in the process. A brief examination of the stakeholdersÆ requirements is included.

Sep 26, 2011

By M Recabarren, A Echeverria, J Ronda, J I. Guzman, R Dodds, G Juarez, E Vila-Echague

A strategic mine plan is a fundamental part of any mining operation. It must provide a realistic and operative extraction and processing schedule, and yield the highest value for the business. For open pit mines, the problem can be modelled as a set of blocks representing the deposit, for each of which we need to decide if it is going to be mined, if so, when and where it will be sent (process, stock or dump).This problem can be proven to be of NP-Hard complexity. The traditional approach used by mining engineers to tackle this complexity is to separate the problem into more tractable components, solving each separately. The first step is to use the Lerchs-Grossman (LG) algorithm to obtain the final pit limit, as well as a set of optimised pit shells (nested pits), using different input prices. Then, using this input, operational phases are designed. Third, the set of phases can be used as an input for a phase-bench style optimisation, usually using a mathematical programming-based algorithm.There are, however, several problems with this approach. First, dividing the problem into simpler parts has the consequence that any compromises made at early stages limit the potential value left for the following steps. Second, LG is a static algorithm, with no concept of the time-value of money, capacity limits, opportunity costs, etc. Phase design is essentially a manual step, for which nested pits provide insufficient information in practice, and therefore the quality of the result in terms of potential net present value (NPV) depends strongly on the experience and expertise of the designer. This means that key input data such as commodity prices, different processes capacities and mine movement limits, are considered only at scheduling, when there is little room for optimisation. This sequential approach limits the potential value in each step, where a simplified problem is addressed, instead of addressing the real, and more complex problem, which is dynamic and should be solved as a whole.We present in this paper an algorithm, and its commercial software implementation, that addresses the dynamic problem as a whole, simultaneously and automatically creating a high-value strategic mine plan that adheres to basic operational constraints, determining dynamic cut-off grades and delivering a set of phases which can serve as a much stronger guide than nested pits for the final design. We discuss some of the key elements of the algorithm and propose a new methodology for strategic mine planning, where phase design dynamically responds to mining strategy definition. Results using different mining and operational parameters on a fictitious copper deposit are used as a demonstrative example.CITATION:Juarez, G, Dodds, R, Echeverria, A, Guzman, J I, Recabarren, M, Ronda, J and Vila-Echague, E, 2014. Open pit strategic mine planning with automatic phase generation, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 147–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

The modern resource extraction enterprise is a complex capital intensive business operating in a world of constantly evolving social, environmental and economic scrutiny. Investors, government, media and special interest groups expect to see business environmental and social performance respond and deliver increasing corporate responsibility and sustainability.   Thorough interrogation of business performance using a multi-disciplinary due diligence approach presents a more sophisticated review and benefits beyond the traditional compliance/conformance 'audit' style assessment.   Using a due diligence approach allows assessment through a comprehensive lens which examines potential short- and long-term risks including sometimes less tangible environmental and social liabilities, and informs management, investors and regulators of broader business performance. This approach provides information in a form that business can measure performance in a repeatable and enterprise wide sense.   This paper provides an outline of the due diligence process applied in this way, drawing from lessons learnt and industry based experiences in the due diligence process and the benefits and tools that can  be applied in an environmental and social due diligence business performance assessment

Jun 1, 2010

By W Stange, N Hanson

An important aspect of the project evaluation process is the achievement of a clear and quantitative understanding of the primary drivers influencing project value and risk. A business scenario-based approach is required to ensure that the project meets value and risk hurdles over the short, medium and longer term. Adopting an optimising approach can aid significantly in the development of a project concept into a business that is optimal and sustainable in the longer term. Through the application of case studies, based on work performed with various mining organisations during the last five years, this paper will demonstrate how project value and robustness can be optimised. Experience has demonstrated that applying this approach results in significant value improvements and risk reduction û primarily by application of a rigorous, fact-based analysis and optimisation process that rapidly increases management team understanding and insight of key driver of value and risk.

Jan 1, 2007

Martha Mine is an open pit gold-silver mine, located within the township of Waihi, 150km southeast of Auckland and is operated as a joint venture between Normandy Mining Ltd. 67 %) as Manager and Otter Gold Mines Ltd. (33%). The deposit was historically mined, by underground methods from 1888 to 1952, producing 5.5 moz of gold and 30 moz of silver, from 11 mt of ore. The current operation began in 1988, producing, to June 1999 - 867,245 oz of gold and 5.5 moz of silver from 9.5 mt of ore. The licensed reserves were due to be mined out by late 2000. Consents were granted in December 1998 to allow the expansion of the operation through to 2007 accessing an additional 7.5 mt of ore at 3.4 gpt Au and 26.0 gpt Ag for 800,000 oz of gold and 6.4 moz of silver. The key elements of the expansion are: 1. Pit enlargement 2. Upgraded crushing and material handling facilities 3. Construction of a second tailings storage facility 4. Upgraded water treatment capacity 5. Increased operating capacity This paper presents an update of expansion activities to date.

Jan 1, 1999

By T Hicks

Designers of mining facilities play a significant role in defining the overall mine greenhouse gas emissions performance. This demands an appreciation of all the greenhouse gas emissions sources, including Scope 3 emissions, which will form an increasing fraction of the emissions as we transition our generation sources to renewable energy. Traditionally overland conveyors are designed to operate as fast as practical, and through this approach, achieve relative minimisation of: conveyor belt tensions; belt width; mechanical equipment masses; structural steel quantities; and concrete quantities. It is well understood that higher belt speeds reduce capital cost and improve project economics. Operating at higher speeds introduces operating costs through system energy losses and increased wear rates. This paper assesses the life cycle greenhouse gas emissions for a typical iron ore overland conveyor to demonstrate how the design criteria and engineering decisions impact greenhouse gas emissions and project economics. An analysis of the decarbonisation potential and project economics using a range of operational parameters has been completed, developing a marginal abatement cost for each system configuration, creating a basis for integration of low emission overland conveyor designs as part of the broader facility decarbonisation strategy.

Sep 1, 2024

By J Darbritz

"This paper details the events leading up to a slope failure that occurred at Kalgoorlie Consolidated Gold Mines (KCGM) and the remediation method executed using rope access specialists.n January 2016, KCGM Fimiston Pit experienced a double bench wall failure where approximately 80 000 t of material fell from the wall that blocked access to a ramp and caused minor damage to equipment.The event was triggered by heavy rainfall and occurred along unfavourable eastward dipping structures that lead into weaker shale/porphyry bands, which in turn left more material on the face. A remediation plan was formulated that would allow for the continuation of open pit operations while a full geotechnical assessment of the failure area could be conducted. This was accomplished by means of rope access specialists who abseiled down the wall and blasted off the remaining overhang using a portable drill rig and prepackaged explosives.This paper provides a brief overview of the KCGM operations, how the instability was identified and monitored, details of the failure event, outcomes of the geotechnical assessment and details on the remediation work.Citation:Graf, C and Sullivan, R, 2016. The Journey to Steepening the Pit Slope Angle - Advancing the Effectiveness of Wall Control, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 104–114 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By D Morton, G Wallace

"Evolution Mining is the sole owner of the Mt Rawdon open cut operation, located 75 km south-west of Bundaberg in Queensland, Australia (Figure 1). It is a massive, volcanically hosted, low-grade gold deposit that exhibits excellent characteristics conducive to low cost mining and treatment.In 2014, Mt Rawdon began investigating initiatives to deliver higher mill throughputs without any significant capital expenditure or modifications to the existing processing plant. Various studies have shown throughput increases are possible by applying more blast energy, essentially by reducing feed size through blasting and leaving less work for the comminution circuits (Brent et al, 2013; Ziemski, 2011; Workman and Eloranta, 2003).Given that 53 per cent of energy used on a mine site is consumed by the comminution circuit, with only two per cent being consumed by drill and blast (Smith, 2013), it makes logical sense for a mining operation to align their drill and blast with their processing plant. The term commonly used when exploring this relationship is a ‘Mine to Mill’ program.Over nearly 12 months, various blasting options and Mine to Mill methodologies were tested at Mt Rawdon. Throughout the journey, it was abundantly clear that the Mine to Mill initiative is not as simple as making one technical or physical change and expecting an improvement. Rather, true sustainable improvements demand a paradigm shift across both the mining and processing cultures, where all departments are aligned and working towards the one outcome. This true overarching Mine to Mill mentality, enabled by Vistis™ 250 high energy bulk explosive, ultimately led to a sustained increase in throughput and profitability of the Mt Rawdon operation.Citation:Wallace, G and Morton, D, 2016. High Energy Bulk Explosives and Mine to Mill Focus – the Mt Rawdon Story, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 60–69 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By D MacKay

The Mt Wright Project is located near the town of Ravenswood in North Queensland and is operated by Carpentaria Gold – a wholly owned subsidiary of Resolute Mining Limited. Underground Development of the current Mt Wright orebody commenced in June 2006 and the first production ore was brought to surface in June 2007. The orebody is a rhyolite pipe containing fine-grained disseminated gold in a granite host rock. Ground conditions tend to be good to excellent throughout development, with some minor deformation experienced when stope-sized excavations are formed. The mine commenced as a sublevel open stoping (SLOS) operation with the intent to utilise development waste to back fill isolated upper level stopes while developing to the bottom of the known orebody. The mine plan intended to commence production with a bottom-up primary/secondary stoping retreat through the main orebody utilising cemented fill. Some challenges were faced during the initial production phase that included:•Ongoing underground diamond drilling and updating of the block model resulted in some issues reconciling the grade control results to the resource model. This was primarily due to the high variability of grade which in turn caused difficulties in accurately identifying areas of low and high-grade.•The cost of establishing and operating a cemented fill plant to achieve the planned extraction sequence of the orebody had increased significantly beyond initial estimations.•Geotechnical conditions such as stress orientations, ground behavior and response to the forming of excavations learned through the mining of the upper level stopes were different to the assumptions made during the initial design.A number of in-house and external reviews of the mining method were completed which has resulted in a revised mining plan. This paper will summarise the challenges faced and the implementation of the mine plan to date.

Mar 21, 2011

By P Davidson

For many years, in numerous settings, the need for a language-fair and culture-fair assessment test has been identified as a significant issue for employment and selection for training of remote indigenous community members. Pivotal to the successful implementation and application of such a test is for it to gain the acceptance and trust of the local indigenous communities as a fair assessment and for it to provide organisations with an accurate predictive tool. However, when western tests have been used with indigenous groups, inherent language and cultural bias have had a significant negative impact in terms of community acceptance. These have also affected the accuracy of performance predictability. The Queensland Test was developed to overcome these problems. Originally developed for use in Papua New Guinea, it reduced training failures by 20 per cent. Later refinements were made and it was used with Aboriginal Australians. Since 2002, assessment tests have been used by the Freeport mine in West Papua to support their recruitment, selection and training processes for the local indigenous community, the Seven Suku Tribes. The initial process included the application of standard æwesternÆ assessment tests, which did not provide valid selection predictions, with community members and elders describing these tests as unfair and the organisation being concerned that the results were not accurate. A trial of the Queensland Test was conducted and a high correlation was established between the performance of FreeportÆs current Seven Suku employees as assessed by their managers and their Queensland Test results. Based on the results of this pilot the Queensland Test was successfully implemented as the primary selection tool for potential employees from these local indigenous groups. The testing materials and method gained community trust and support, with tribal elders describing the Queensland Test as a fair and suitable selection tool for their community members. Such results have sparked an interest within the Australian Mining industry, with similar results being reported from a recent trial. The Queensland Test has been implemented at a major site in Queensland and is being investigated for use elsewhere.

Jan 1, 2006