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By A G. Dempster, N Barnett, J Oh, S Saydam

NASA’s Artemis III mission is expected to return astronauts to the surface to explore and sample the lunar volatiles by 2026. These volatiles are anticipated to provide scientific insights as to how the Moon was created and economic value to off-Earth operations. These same volatiles can pose health implications to astronauts and Earth based personnel handling lunar regolith samples. Using Australian, USA and NASA airborne contaminant exposure limits and the Lunar CRater Observation and Sensing Satellite (LCROSS) measurements of lunar volatiles in the Cabeus crater ejecta, the minimum mass of lunar regolith that can be safely handled by humans on Earth and in spacecraft can be calculated. This analysis determined a 0.15 grams pure sample of Cabeus crater regolith within a cubic metre of air has enough volatiles to exceed safe working conditions, and 14.9 grams of pure Cabeus crater regolith per cubic metre of air can impact human life. The intent of this analysis is to assist safe handling and exposure calculations for the safe handling procedures of lunar regolith containing volatiles.

Sep 1, 2024

By D A. F Oliveira, C J. Parker

The role of the virgin in situ stress field in tunnelling projects is well known in the Sydney area. The effect of in situ stresses is mostly considered through the use of published relationships that describe the in situ stress conditions as a function of depth. Considering the significant scatter in the data, it is evident that by adopting such relationships, the designers are assuming an average distribution of stresses with depth that is generally a reasonable engineering approach; however, when building a geomechanical model, the tunnelling or geotechnical engineer needs to account for the interrelationship between ground conditions (rock mass quality – fracturing, strength and stiffness) and in situ stress, which may explain part of the stress data scatter. This paper presents an alternative approach for interpreting in situ stress conditions, valid for both Sydney sandstones and shales that focus on such interrelationship between in situ stress and ground conditions.CITATION:Oliveira, D A F and Parker, C J, 2014. An alternative approach for assessing in situ stresses in Sydney, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 189–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Following unprecedented high market prices for tin and gold in 1980, significant advances in both mining technology and geological knowledge took place in northeast Queensland. These led to a rapid growth in mining activity. Production of these traditional metals reached levels comparable to those of the heyday of mining activity at the turn of the century.Although tin and tungsten prices have since collapsed, the geological knowledge gained and significant discoveries made during the boom, have created a potential for mine development when prices rise again. For other discoveries which are not workable because of treatment problems, future technological advances are required to raise their potential.

Jan 1, 1990

The development of the lower Hunter Valley, centred around Newcastle and its suburbs is closely linked to the mining of coal and the settlements which grew to house the colliery officials, the miners and their families. The Port of Newcastle expanded and developed as a port exporting coal to many ports of the world ranging from Hawaii and Brazil to Japan and Korea. The coal which passed through the Port of Newcastle, depend- ing on the historical period in question may have been mined in Newcastle itself, or one of the nearby colliery townships such as Lambton, Wallsend, Charlestown or Hamilton, or from one of the estuarine collieries located at Carrington or Stockton or from the West Wallsend area or from East Greta, Pelaw Main or Cess- nock located on the South Maitland (Greta) coal field or from the open cut and underground mines of the Singleton Coal District.

Jan 1, 1988

By D Tanzil, H Jones

Every mine will close! Charting a profitable course through mine operations to acceptable mine completion requires that risk and opportunity management planning of the mine life begin as early as possible in the life cycle. Management targets and metrics are required to identify and navigate the course to successful mine completion based on economic, social and environmental criteria. This paper outlines the application of The Metrics NavigatorÖ principles to the life cycle of a mine site. In general, metrics are required to make key strategic ideas apparent, transforming those ideas into a manageable set of quantitative measures that guide communication and decision making. For example, the chemical industry has established metrics that focus on the life cycle impacts of its products and eco-efficiency of their processes. Other industry sectors have focused attention on workplace and community well-being outcomes. These management metrics are necessarily organisation-specific, aligned to stakeholdersÆ expectations and the strategic outcomes sought, as well as the cause-and-effect relationships underlying key issues. Recently, the Global Environmental Management Initiative (GEMI), a consortium of multi-national companies, developed The Metrics NavigatorÖ. The guidance document provides a structured process for assessing and developing metrics for key environmental, social, and economic issues based on business and stakeholder perspectives. It incorporates best practices learned from the chemical and other industry sectors and has since been applied to develop metrics that guide life cycle strategies. The paper examines how the life cycle of a mine site could benefit from experiences in other industry sectors where sustainability metrics have guided strategy. It considers the potential application of The Metrics NavigatorÖ process to the life cycle of a hypothetical Australian mine site using the processes that have been successful in other industry sectors.

Jan 1, 2009

By C Czerny, T Elkington, L Lorenzen

The Dutwa Nickel Project is a nickel laterite atmospheric leach project located in Tanzania that has been under development by African Eagle Resources plc (2012). A bankable feasibility study (BFS) has been progressed to evaluate mining of the resource (107 Mt at 0.92 per cent Ni) followed by hydrometallurgical processing on-site to make a mixed nickel-cobalt intermediate product. The unique relatively high silica contents in the Dutwa deposits, as opposed to limonite, which is more commonly occurring in nickel laterites, presented the possibility for beneficiation of the ores to enhance the leach feed nickel grades and provide economic benefits in terms of operating and capital cost efficiencies.Geometallurgical relationships, based on the results of an extensive variability metallurgical test work program for beneficiation and leaching, were developed for the BFS, which resulted in an improved understanding of ore classifications within the deposit and their responses. The geometallurgical information obtained has been instrumental in making key preliminary techno-economic decisions, such as forecasting whether or not mined material should be beneficiated and was ultimately used to drive the mine plan towards the prioritisation of areas within the deposits that delivered the best cost efficiencies and overall project economic outcomes.CITATION:Elkington, T, Lorenzen, L and Czerny, C, 2013. The use of geometallurgical relationships in process route selection and mine plan optimisation for the Dutwa Nickel Project, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 207-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By E Baafi, G Brassington

Coal mining operations can impact on various types of surface infrastructure or natural features, including cliff-lines, steep slopes and natural watercourses. Longwall mining leads to a subsidence depression due to the changing geometry of the mined out area. The current regulatory process for managing subsidence in New South Wales (NSW) involves the preparation of a Subsidence Management Plan (SMP). This paper demonstrates the use of a Weights of Evidence (WofE) technique applied within a Geographical Information Systems (GIS) environment to predict potential areas for rockfalls along cliff-lines in the NSW Southern Coalfield. The WofE is a ædata-drivenÆ method that can be used to predict subsidence impacts prior to mining. The WofE method was applied to ten known rockfalls along the Cataract River to evaluate the reduced impact of not mining within 50 m of cliff-lines along the Nepean River. There is significant reduction of probabilities of rockfall occurrence when mining is avoided within 50 m of cliffs.

Jan 1, 2006

By H Mansouri, M A. Ebrahimi Farsangi, F Faramarzi

A blast fragmentation model is developed based on the gamma function to describe the run-of-mine fragmentation distribution. The model presented is aimed to benefit from simplicity in application and also to be efficient in description of the fine to coarse part of the blast rock fragments. In fact, the gamma based model (KC-KUM), gives a unit distribution curve, which is made up of two separate equations, covering different fragment sizes in the muck pile. The generated values of the fines to central part of the equation and the central to coarse part of the equation are connected at the 40 per cent grafting point. For validation, eight production blasts, which were specially designed for this purpose, were carried out at an iron ore mine (Jalal-Abad iron ore mine/Iran). Results achieved by KC-KUM and two of the most well-known models. Kuz-Ram and Swebrec, are compared with measured data. Moreover, to assess the models’ efficiency in presenting the best distribution curve, a Logarithmic error method is chosen. Based on the achievements. KC-KUM has the least deviations by the least absolute log error of 0.52, whereas the values obtained for the Swebrec and Kuz-Ram models were 0.79 and 1.34 respectively. Furthermore, the models were applied to predict X80 for 12 production blasts carried out at Gol-e-Gohar iron ore mine/Iran. These predictions were compared with the results from these trials. The coefficient of determination (R2) and root mean square error (RMSE) are calculated. Consequently, the highest R2 was obtained for KC-KUM at 0.837 with the least RMSE of 11.31. On the other hand, R2 and RMSE are equal to 0.832 and 20.19 for Swebrec; and 0.813 and 19.75 for Kuz-Ram respectively. The results obtained suggest the superiority of the KC-KUM model over the other two models in assessment and prediction of blast fragmentation in a reliable way.CITATION:Faramarzi, F, Ebrahimi Farsangi, M A and Mansouri, H, 2015. Prediction of rock fragmentation using a gamma-based blast fragmentation distribution model, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 685–692 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Daoust G, Dubois JF

The optimal sequence of decisions on rates of production and cutoff grades is obtained by a dynamic programming model. The main parameters are : 1. the size of the deposit, average grades and grade distributions, 2. the operating costs of mining and concentration, 3. the investments in mine and mill, 4. the smelter charge, 5. the price(s) of the metal, 6. the recovery and the grade of the concentrate, 7. the rate of interest, 8. the taxation formulae, 9. the upper limit to rate and the rate interval and 10. the upper and lower limits to cutoff and the cutoff interval. An amount of ore can be mined at various rates while applying various cutoff grades. It is assumed that a decision to mine at a certain rate during a period conducts to a certain state regardless of the cutoff grade. This assumption which is valid for several

Jan 1, 1977

By P Hatherly, A Melkumyan, D Wyman

Chemical species distributions in rock sequences can be modelled using Gaussian processes (GPs) to predict the weight percentage between known data points. This method can be improved by dividing the modelled area into regions of different mineralogy. In the context of many iron ore deposits, marker shales give the initial guidance of where these regions may lie. These shales give rise to distinctive peaks in the natural gamma downhole logs, which are conventionally identified by hand. A GP method has been developed to automate this task.Once the appropriate boundary has been located on the basis of shale occurrences, chemical assays from exploration drill holes are used to find the exact boundaries of interest. These boundaries divide the drill hole stratigraphy into regions of different mineralogy, each of which display their own distinct correlations between the main elements and oxides (Fe, SiO2 and Al2O3). Iron ore shows a negative correlation between Fe and Al2O3, but in banded iron formation (BIF) there is a positive correlation between these species. Similarly, SiO2 and Al2O3 have a positive correlation in the shales and ore but a negative correlation in the BIF. Correlations obtained within ore-, BIF- and shale-dominated regions are therefore better than those obtained using the entire log and can be used to improve the results obtained when modelling.

Sep 26, 2011

By Glasson K. R

The history of Ore Reserve classification and reporting in Australia is largely a history of the Australian mining industry itself. In the late 1800s, when the industry was dominated by small scale, high grade underground mines, Reserves (if estimated) were based on hand sampling and geological inference, and reporting of Reserves was either non-existent or of extremely variable quality. By the mid-20th century, the industry was dominated by large underground base metal and gold mines. Reserve estimation was coming under the control of skilled geologists and mining engineers, however Reserve classification and reporting standards continued to vary in type and quality from mine to mine. Today, large scale, low grade mining operations predominate, and Reserve estimates are generally based on extensive drilling results processed (with geological control) by computer. Through the efforts of a Joint Committee established by The Australasian Institute of Mining and Metallurgy and Australian Mining Industry Council, Reserve and Resource classification and public reporting has been standardised and controlled by adoption of the ""Australasian Code for the Reporting of Identified Mineral Resources and Ore Reserves"" released in 1989. The Code, which will continue to be modified and improved by the Joint Committee, has also been used as a basis for guides to reporting in other countries, and there is now some hope that this difficult and vexing topic may finally become subject to international standards and controls.

Jan 1, 1992

Of the energy resources present in Australia, coal and uranium are by far the largest. These two resources ap- pear sufficient to satisfy Australia's energy needs beyond the immediately foreseeable future and long after the natural petroleum resources are exhausted or have ceased to play a significant role. By that time, coal could be converted in plants of very large size to synthetic liquid and gaseous fuels which will be used as substitutes for pet- roleum fuels, particularly for transport. The basic role of uranium will be to supply electricity from nuclear power stations for heat and power requirements, thereby freeing non-coking coal largely for conversion purposes. The establishment of these enterprises will require a massive national effort and a high degree of co-ordination at the planning stage.

Jan 1, 1975

Gold mineralisation at Wapolu lies within an exposed arcuate zone at the decollement contact between a basement dome of high grade metamorphics and an overlying ophiolite sequence. This contact was originally a thrust fault which has since become a decollement zone for gravity sliding in association with basement doming. Hydrothermal models for the gold mineralisation postulate an epithermal system in which fluids were channelled up the decollement with boiling of those fluids causing hydrothermal brecciation and subsequent gold deposition. The alteration assemblages, fluid inclusion data and geochemistry indicate that the upper levels of the system are exposed.

Jan 1, 1987

By P K. Seccombe

The McKinnons gold deposit is hosted by weakly deformed, Palaeozoic metasedimentary rocks of the Cobar Basin in the western Lachlan Fold Belt of New South Wales. Mineralisation comprised a largely supergene resource of 1.7 Mt of ore, grading 1.7 g/t gold, established over structurally controlled, primary gold and base-metal mineralisation in underlying, carbonate-rich meta-siltstones and sandstones of Early Devonian age. Mineralisation was associated with at least two major fluid cycles. The first cycle was characterised by four stages of vein formation. Early quartz and carbonate veins (Stages 1 and 2) and quartz-pyrite breccias (Stage-3) occurred prior to, or early in, the main regional deformation (D1). Continued D1 deformation produced syntectonic, carbonate-base-metal veins (Stage-4), primarily in dilatant zones adjacent to fold axes. The second cycle of mineralisation was an epithermal-style event, driven by a shallow, syn-D2 or post-tectonic intrusion, defined by aeromagnetic imaging. The intrusion may have exploited a jog, controlled along the basin margin by basement faults. Mineralisation produced gold-pyrite veins, associated with pervasive quartz-sericite-adularia and chlorite-sericite alteration. Highest primary gold grades are confined to quartz-adularia boiling zones. The McKinnons deposit offers an important example of mineralisation formed by multiple processes. Early-stage, base-metal mineralisation at McKinnons reflects structurally focussed, basin dewatering and metamorphic processes, typical of other deposits in the Cobar Basin. By contrast, late-stage gold mineralisation at McKinnons is magmatically driven and of epithermal style. Recognition of overprinting distinctive geological events is critical, not only in modelling ore formation, but in developing a versatile exploration concept.

Jan 1, 1999

By R C. Schodde

The future of any mining company depends on maintaining and growing its access to high-quality mineral resources. Often the true size of a given resource is not fully recognised until after mining has commenced. Also, the strong desire to increase production puts pressure to expand the resource base of the mine to get maximum value out of the capital employed. This, plus diminishing M&A opportunities and declining world-class greenfield discovery rates, makes brownfields exploration a high priority activity in any operating company. For the success and long-term survival of the company it is critical that this is done well. The primary aim of brownfields exploration is to find or acquire new deposits within economic transport distance of an existing mine that will add materially to shareholder value through: mine or capacity expansion, displacement of lower-margin ore from the mine plan, preserving and extending the mine life, and ensuring potential value is understood in order to maximise potential future mine development or exit. A number of strategic principles are important in any program designed to achieve these aims: understanding the life of mine (LOM) production profile and the related key drivers for exploration, understanding the dynamic nature of the brownfields search space, understanding and measuring depletion of the brownfields search space, understanding the potential of the near-mine region, investing in exploration technology to expand the search space, and investing in a basic geological understanding of the ore-environment. Examination of the LOM profile will highlight critical issues facing development plans for the mine including future grade and throughput issues, key technology requirements or innovations and scenarios for increased production. Exploration targets in the brownfields program should address these key issues. Often it is as æsimpleÆ as keeping mine development sufficiently far ahead of extraction to allow time for the various phases of exploration and resource assessment drilling. Because of the low additional capital costs required, expansion of the brownfields search space is strongly leveraged to: metal prices, development of new markets, incremental operating cost reductions, strategic changes in downstream requirements in integrated businesses, depletion of higher unit-value ores, and new technologies (both extraction and exploration). Therefore the brownfields search space is likely to incrementally expand through time and must be regularly reviewed. This is also important as any given search space will be progressively exhausted, resulting in smaller and higher cost discoveries. It is therefore important to monitor and critically review sustained trends of increasing brownfields discovery cost. The first wave of discoveries in any camp are usually empirically driven and do not need a strong geological understanding. However, an improved geological understanding is critical to making the next generation of hidden discoveries. To illustrate these points, a case study was carried out on the exploration and development history of the Kambalda nickel camp. Over a period of 40 years, more than 40 deposits were found containing over 1.7 million tonnes of nickel metal. Efficient mines need to maintain reserves for operating flexibility. Consequently, the company needs to clearly understand the global resource in order to maximise its full potential. In addition, understanding the full brownfields potential earlier in the development of a deposit rather than later, creates optionality through the flexibility that this understanding brings to future development choices. To ensure best practice in attaining this aim, the roles and responsibilities of the exploration team and the mine operation should be clearly understood. It is important for the explorers and the operators to have shared views about what needs to be done. Typically, mine operators would be accountable for identifying future resource requirements to support the life-of-mine production schedule whilst explorers would be accountable to ensure best-practice assessment of brownfields exploration opportunities. This would include an assessment of the global undiscovered endowment in the regional near-mine area. The balance between brownfield exploration drilling and resources to reserve conversion will need to be decided to ensure efficient operations are maintained. Both need to agree the optimum level of brownfields funding taking into account: urgency to replace or grow reserves, and quality of opportunities (relative to those elsewhere). The ultimate cost of ignoring the full brownfields potential of an operating asset can be significant, ranging from inefficient and poorly planned operations, lost opportunity cost and resultant value through under-utilised resources and, in the worst case, early exit from the asset at the bottom of the commodity cycle û leaving behind huge amounts of shareholder value.

Jan 1, 2006

By M Flanagan, T Sua, B Wright, T Carroll, B Van Dijken

"BHP Billiton (BHPB) West Australian Iron Ore (WAIO) conducts an extensive geometallurgy (geomet) program for its iron ore deposits in the Pilbara. The geomet program provides accurate information to infrastructure engineers, resource geologists, mine planning engineers and the technical marketing team on the performance characteristics of iron ores. Performance metrics include production planning, such as lump/fine splits, processing capability such as the level of ultra-fine iron ore and ironmaking blast furnace properties including tumble index (TI) and reduction disintegration index (RDI). Prior to the introduction of the current geomet program in WAIO, basic geometallurgical information was provided at the deposit level, such as deposit lump percentage and head grade chemistry. As the business value of geometallurgy was realised during the growth period of WAIO, the geomet process was reviewed and formalised into five steps: geomet drill planning laboratory measurement data management algorithm development block estimation.The geomet laboratory process produces simulated iron ore products from drill core, which are then subjected to physical geometallurgy test work. With the large amount of geometallurgy data collected, extensive databases are utilised to collate and organise the data to improve its usability within the business. Algorithms are created from the data to predict important geomet variables and a block estimation method is used to estimate geometallurgical properties into resource models. The predicted geometallurgy data is regularly reviewed at the different steps against plant and shipping data to allow refinement of the geometallurgy algorithms. It is also recognised that geomet data can be used to optimise the operations in existing processing hubs for improved production rate. In addition, future geomet programs will focus on generating data from all available drill core programs, not just dedicated geomet drill holes, and will incorporate new types of data, such as hyper-spectral information, for improved geometallurgical estimation.CITATION:Wright, B, Carroll, T, Flanagan, M, Sua, T and Van Dijken, B, 2013. BHP Billiton West Australian iron ore geometallurgy - past, present and future, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 105-110 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

By L Rattmann, T Katz, J B. Pateiro-Fernßndez

Carbon capture and storage (CCS) is expected to become one of the main technological instruments for mid-term reduction of CO2 emissions into the earthÆs atmosphere. Besides the reduction of CO2 emissions into the atmosphere, the implementation of CCS would have various negative consequences, which are û if at all û only poorly covered in the current socio-political discussion. Taking into account all aspects of CCS, the outcome of a comprehensive and conclusive assessment of CCS against the background of the sustainable development concept is uncertain. When assessing the overall impact of CCS in a holistic approach, a variety of aspects with effects on sustainable development are affected. Besides economic issues, various other effects of implementing CCS should be taken into consideration. These include for example additional costs for CCS facilities and processes and a decrease in powerplant efficiency due to high energy requirements of capture processes, and various ecological and societal aspects, such as higher demand for combustible, resulting in faster depletion of reserves and higher land and water use and the provision of jobs along CCS technology chain. This paper presents an approach for a structured sustainability assessment of CCS based on the multi attribute decision-making (MADM) method analytical hierarchy process (AHP). The functioning of the presented methodology is exemplified at the case study of a German coal fired powerplant.

Jan 1, 2009

By P Tobar

The development plan (long-term plan) of El Teniente Mine, Codelco-Chile, includes 100 per cent primary ore, located at increasing depths, which may involve several difficulties related to the application of the current panel caving method, such as a high seismicity level, a coarse fragmentation and ore pass damage. Therefore, it is a strategic priority for the El Teniente mine, to design and to test alternative mining methods, at similar or lower costs to ensure an efficient and safe ore extraction. In this context, the Macrotrench method is developed, as a competitive alternative to the current method. The document describes the panel caving method, the experience achieved in the primary ore exploitation from the geomechanical point of view. It also describes the æmacrotrenchÆ method as an alternative to the current exploitation method. Finally, the comparative advantages of macrotrench in relation to panel caving are presented. The results obtained during the engineering stage include the following aspects:the mining design, the material handling, a geomechanical evaluation of the method, and a comparative analysis.

Jan 1, 2000

By C OÆKeefe, A Thomas

Boom time in the mining industry has presented mill operators with several unique challenges including the need for increased throughput while being constrained by a shortage of skilled labour and aging capital equipment. New instrumentation technology that provides reduced installation costs; no process down time for installation; and reduced maintenance costs and labour requirements; has been introduced to address the labour situation while maintaining production. This new tech- nology also enabled more accurate and reliable process measurements thus providing the capability for operators to maximise throughput with their existing capital equipment. This passive SONAR based technology can accurately measure the volumetric flow rate of single phase and multiphase fluids as well as the amount of air entrained within slurries. This is accomplished in a non-invasive manner. This paper will describe the principle of operation as well as the application of the technology to critical minerals processing applications. Included will be operational examples comparing the SONAR measurement performance to traditional measurement techniques. These examples will include hydrocylone feed flow, flotation concentrate flow, and slurry streams containing magnetic ores. Actual plant data will be presented as well as a discussion on the operational advantages such a measurement capability.Also described will be the power of the technology platform to provide novel process monitoring and control capabilities such as pipeline sand-out prevention and pipeline acoustic monitoring.

Jan 1, 2009

By Biswas AK

The solubility of nickel in matte smelt- ing slags, both as oxide and in the metallic form, is predicted using the results of a recent experimental work carried out with lime- free iron silicate slags as well as slags containing lime. Predicted solubilities are much lower than the nickel content of smelting slags, indicating that entrapped and possibly dissolved matte could be the major cause of nickel losses in such slags.

Jan 1, 1975