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By S Maritsa, D Simbi, E K. Chiwandika, S M. Masuka

The steel industry is facing challenges on a global scale that include depletion of resources, huge energy consumption, and the emission of CO2. The demand for iron products is increasing due to the increased infrastructural development. Zimbabwe produced cast iron from scrap metals. However, there is currently a shortage of scrap, and yet Zimbabwe is rich in limonite ores that are currently being underutilised. The possibility of using limonite ore as a sustainable feed for pig iron production was investigated by preparing some limonite ore carbon composite pellets. The results showed that the addition of coal to the limonite ore and calcium carbonate mix to form the composite pellets resulted in a decrease in the drop number as well as the dry compressive strength of the composite pellets. This research aims to improve the physical properties of the green pellets by the careful addition of hydroxyethyl cellulose as a binder that was found to improve the physical properties of the green pellet. This is important for materials handling during the production process of the composite pellets. Results showed that the drop number was substantially improved by the addition of 0.4 wt per cent hydroxyethyl cellulose while the dry compression strength improved from 2.5 kg/pelIet to around 23 kg/pellet irrespective of the amount of binder added. The binder improved the physical strength of the iron-carbon composite pellets enough to allow for large-scale production of the pellets that can be an alternative and sustainable feed for cast iron production. However more results on the indurated compression strength and other properties such as the reduction degradation index, swelling index, and the reducibility test are required.

Jun 19, 2024

By R Lau

The fire safety design for road tunnels includes the following aspects: active systems, passive provisions and operational procedures. The active systems include the smoke control system, fire suppression system, detection system and fire fighter’s assistance systems. Passive provisions include escape passages, fire separation and fire resistance systems. The operational procedures refer to fire fighter access, reporting and alerts, evacuation processes and crowd control.Currently, these systems are typically designed by different designers or teams. These systems are intended to work together in a coordinated manner to provide the desired safety outcome. However, in practice, this is not always happening. The fire engineering process is supposed to bring together all these aspects and arrive at an integrated safety system. The fi re engineering process in practice is not integrating the design with the practice or reality and is thus arriving at less than desirably efficient safety systems.The example of design inputs shows how disconnected each system design basis is. The smoke control system design is based on the design fire size. The performance of the smoke control system is to achieve a smoke free environment for a defined space for a particular fire size – the design fire. The fire suppression system – most commonly sprinklers or deluge systems, is designed according to codes and to achieve a certain water discharge rate. The fire detection system is designed to detect temperature rise/rate of rise and perhaps density of smoke. Fire separation is determined to provide a certain period of service – mostly for structural elements. Escape route size and location is determined mostly by code compliance. Evacuation procedures are determined by Authority operational requirements rather than human behaviour.To arrive at an integrated fire safety system, the design basis and performances must be coordinated. An approach using fire scenarios would ensure all systems are designed to a common performance requirement. This paper will discuss how the current design approach outcomes compared with a fire scenario approach. More effective and efficient fire safety systems would require the stake holders to understand the implication of this approach and to embrace this through the fire engineering process.

Mar 8, 2011

By B Robertson

Over the 40 years that the author has been engaged in the Australian underground coal mining industry, there has been a continuous improvement in safety performance as the sector has grown in size and productivity. The underground environment hosts many hazards with significant risk profiles that are kept in check by effective health and safety management systems that have evolved largely following major underground disasters. Observations are made on the changes observed for specific aspects of the underground coal sector, with particular reference to ventilation issues, and predications are made as to the needs of the future.CITATION:Robertson, B, 2013. Past achievements and future challenges in the underground coal sector, in Proceedings The Australian Mine Ventilation Conference , pp 27-32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

Drilling underground can be a hazardous undertaking in many circumstances. Raiseboring and boxhole boring underground could form an integral part of the block caving production methodology and getting the right mix of technical capability, ergonomics and economical viability has been the goal of many machine manufacturers. With the introduction of the Terratec Universal Boring Machine concept, flexibility of raiseboring, downreaming and boxholing has been enhanced by the introduction of a single machine that will perform all three processes. In addition to its technical flexibility, additional safety features have been introduced that will eliminate many sources of injury by mechanising most of the operational procedures. Together with the one-man remote operation, this machine design addresses and solves many of the safety issues. This paper outlines the machine concept, details its safety features and shows the techno-economic advantages for use in the block caving environment. Block caving is a distinct caving method applied mostly to large massive orebodies because of the inherent low costs and high production capabilities. Areas of sufficient size are mined by undercutting so that the mass above will cave naturally. Extraction of the caved ore at the bottom of the ore column causes the caving action to continue upward until all of the ore above the undercut level is broken into sizes suitable for handling (Figure 1).

Jan 1, 2000

By Fazakerley VW

The Murrin Murrin deposit is located about 210 km NNE of Kalgoorlie and 50 km E of Leonora in the North Eastern Goldfields region of Western Australia at latitude 28¦ 50'S. longitude 121¦ 54'E on the Laverton (SH 51-2) 1:250 000 map sheet. The tenements are held by Anaconda Nickel NL. Geological investigations between 1994 and 1996 resulted in resource calculations being completed for the ten lateritic nickel cobalt deposits shown in Figure 1. At a 0.8 per cent nickel cut-off the resources at May 1996 for the nine deposits are 116.8 Mt at 1.10 per cent nickel and 0.082 per cent cobalt. The nickel-cobalt mineralisation is contained in a laterite profile developed over Archaean serpentinised peridotites. A bankable feasibility study has been completed and the project is scheduled to be in production by the beginning of 1998.

Jan 1, 1996

By A Murphy

Mining plants and infrastructure, and the decisions made by their designers, can have large impacts on their environmental and social context, commonly referred to as the site or plant footprint. They can also be the source of constructive contributions to sustainable development when designers are enabled via the information, systems and tools to incorporate sustainability in engineering processes. A facility’s footprint and the project’s contribution to sustainability – economic, environmental and social aspects – are now key considerations in regulatory approval processes and are the fundamental drivers of support, or opposition, from the project’s stakeholders.Historically, plant and infrastructure designers have not been well integrated with the environmental and social professionals who are engaged to pursue regulatory approvals. Despite this, many objectives central to technical and process engineering have in fact contributed positively to a facility’s footprint and indeed its contribution to sustainable development. Examples of these objectives include increasing process and energy efficiency, and minimising the quantities of waste requiring disposal. With the framework of sustainability, mining plant and infrastructure designers are indeed at the forefront of incorporating sustainability into resource industry projects and are central to the process of obtaining regulatory approvals and ongoing stakeholder support. The process of incorporation starts with a shared understanding of sustainability and sustainable development, and continues with project processes that facilitate information and knowledge exchange throughout the project life cycle.CITATION:Murphy, A, 2014. Incorporating sustainability into mining plant and infrastructure design, in Proceedings Life-of-Mine 2014 , pp 637–646 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

Traditional in situ fan flow test methods under accepted standards require determinations to be made of both static pressures and total pressures during testing. This is to determine the resultant velocity pressures, which are vital in the accurate determination of the final fan airflow. These crucial velocity pressure (Vp) determinations are normally determined using simple manometric instrumentation such as an electronic manometer or an inclined liquid filled manometer. There is relatively little noise or fluctuation in the static pressure determinations and they can be quite easily and accurately recorded. There is almost always considerable fluctuation in the velocity pressure determinations though due to the highly turbulent and irregular velocity profile normally found in such in situ installations. This velocity turbulence means that the recording of such data is subject to random human error as the observer tries to average such fluctuations mentally during the observation period. Worse than this, and in the extreme, the recording of such velocity pressure data could actually easily be misreported if, for some reason, persons chose to do so.The author has devised a field method using highly accurate quartz crystal logging barometers to objectively record these velocity pressures. The method eliminates the ability to either mistakenly or intentionally misreport these crucial velocity pressures and is carried out in parallel with the recognised methodology, so result comparisons can be drawn. As such, a far greater level of confidence can be achieved in the final flow performance results than using the traditional more subjective method. Further to this it is difficult and almost impossible to refute the results using this ancillary substantiation method.The accurate determination of fan flows due to the impost of the carbon tax has taken on much more significance given the financial impacts in Australia at this time. The methodology detailed herein can be applied equally for both fan flow compliance testing and the verification of mine airflow data for greenhouse gas emission evaluations.The paper utilises the results of one 24-point pitot traverse to demonstrate the various findings. These include the very wide range of velocity pressures, which were logged at most of the measuring stations. It also illustrates how the method is utilised and compares the results derived from both this method and the more subjective traditional method along with the benefits of logging the velocity pressure results during the testing process.CITATION:Rowland, J A, 2013. Removing some subjectivity from traditional BS 848 and ISO 5802 in situ fan flow tests, in Proceedings The Australian Mine Ventilation Conference , pp 155-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

This paper describes modern long-term mine scheduling and gives an example of its application. It then discusses the obstacles to the implementation of such schedules.

Sep 26, 2011

By Y T. J Kwong

With the recent emphasis worldwide on environmental protection and sustainable development, finding an enriched mineral deposit no longer guarantees mining development. Only if the identified resource can be exploited in an environmentally-friendly manner is it possible that a mine may be developed. Designed primarily to aid with exploring for similar deposits of a particular type, traditional genetic ore deposit models tend to ignore the fact that all mineral deposits are characterised by type-specific environmental signatures. In fact, how an ore deposit can be mined, the commodities of interest extracted and the resultant mine wastes managed are all largely dictated by the geology and mineralogy as well as the environmental setting of the deposit. An environmental ore deposit model integrates such related information to identify the environmental challenges associated with mining an ore deposit of a particular type and facilitates the selection a suitable combination of methods to minimise environmental risks and impacts. Given that environmental management consumes a large portion of the budget for a modern mining project, making informed decisions at all stages of mining development can reduce the overall project cost. Through case examples, this paper demonstrates how environmental ore deposit models may be useful in mine permitting, active mining and in site decommissioning. It is only through an innovative and flexible approach that the mining industry can shed its tarnished image and gain the social license to mine.

Aug 22, 2011

By K Young, M Martin, D Payne

This paper outlines the evolution of managing high consequence risk scenarios in BHP Coal, with particular focus on managing the stability of an endwall that is adjacent to a public infrastructure corridor running through a Central Queensland coalmine. BHP Coal developed a Geotechnical Consequence Register after industry failures identified shortcomings in traditional risk assessment practices. Traditional risk assessments consider the consequence and likelihood of a geotechnical event occurring under normal operational conditions. As such, the risk rating for a high consequence, low likelihood failure may fall within the acceptable range, even where a lack of meaningful geological data exists due to the area being off lease or outside of mining reserves. The Geotechnical Consequence Register lists all geotechnical failure scenarios of high consequence, identifies if current controls are adequate, and highlights if specific Geotechnical Management Plans are required. This case study reviews a failure scenario that was identified through the geotechnical consequence register. The scenario had previously been considered low likelihood and subsequently driving a low risk; however, the likelihood ranking was impacted by a lack of geological data outside of the mining lease and predominately informed by an acceptable historical slope behaviour. Additional exploration identified previously unmapped faulting which increased the risk rating. The requirement to develop a specific management plan resulted in an increase in the required factor of safety, design changes, the implementation of additional monitoring and a corresponding monitoring Trigger Action Response Plans (TARP). In the case study area, the initiation of a geotechnical instability was identified early through the increased monitoring program. The instability was successfully managed and any impact to the infrastructure corridor off lease was prevented. BHP Coal has used the Geotechnical Consequence Register for several years to identify and assess high consequence geotechnical failure scenarios. In some areas this has justified additional exploration, more stringent design acceptance criteria and an increased level of geotechnical monitoring. The process has been successful in ensuring that geotechnical risk is controlled in areas that often receive less attention than active production areas.

Nov 29, 2022

By A Golsby

Both primary and secondary ventilation is important in underground mining. Secondary ventilation refers to the provision of ventilation to development ends, stopes and services facilities, which constitute secondary circuits tapped off the primary circuit or main through flow of air.An unbalanced primary and secondary combination can cause re-circulation, which is inefficient and potentially hazardous. These inefficiencies extend into operational and other considerations, such as power.Most cost justification analysis covers capital and physical consumables. These analyses are often not comprehensive or holistic. This case study is an example of ‘how to holistically justify’ a secondary ventilation circuit and optimise it to meet all stakeholder needs.This paper particularly addresses the following:how to account for all stakeholders in a secondary ventilation cost justificationthe secondary ventilation componentsthe cost justification outcomes and how to measure themsome of the sensitivitiesthe stakeholdershow to present the justification to meet the stakeholder needssecondary ventilation cost justification.CITATION:Golsby, A, 2015. Secondary ventilation as a value proposition – a case study, in Proceedings The Australian Mine Ventilation Conference, pp 49–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By Wilkins C

The Browns Creek deposit is located 8 kin west of Blayney and 220 km west of Sydney (Figure 1), at lat 33¦32'S, long 149¦10'E on the Bathurst (SI 55-8) 1:250 000 scale map sheet. The total measured, indicated and inferred resource at 30 June 1997 was 1.29 Mt at 6.39 g/t gold and 0.45 per cent copper. During the 1996 - 97 year 263 557 t of ore at 6.30 g/t gold and 0.48 per cent copper was treated, to produce 47 496 oz of gold, and 1 169 t of contained copper in concentrate. As the result of an increase in the resources and reserves, because of underground exploration drilling and accelerated mine development, 1997 production at Browns Creek is predicted to expand from 240 000 to 390 000 tpa, to yield more than 70 000 oz of gold per year.

Jan 1, 1997

By S Chatterjee

The production scheduling of an open pit mine determines the optimal extraction sequencing that significantly impacts a mine’s life as well as net present value. The optimisation of production scheduling of large open pit mines with geological uncertainty is a computationally very intensive process. In this paper, an approximation algorithm is proposed to schedule an open pit mine, where instead of solving the whole problem at once, the production schedule is generated by sequentially solving subproblems. The subgradient method is used to generate the upper bound solution of the Lagrangian relaxed subproblem. If the upper bound relaxed algorithm is not a feasible solution, a mixed integer programming is solved on the generated upper-bound solution. An application at a copper mine with an orebody represented by 16 532 mining blocks is presented using the proposed algorithm. Results show that all constraints are satisfied. The net present values are also calculated and results reveal an 11 per cent higher net present value (NPV) is generated when compared to the NPV generated when the same approach is applied to the deterministic model of the deposit where uncertainty is not accounted for.CITATION:Chatterjee, S, 2014. Stochastic production scheduling – solution through Langrangian relaxation with the branch-and-cut algorithm, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 323–328 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By N Johansson, D Johansson, A Beyglou, H Schunnesson

As demand for optimisation of mining processes increases, more attention is drawn to blast performance and fragmentation improvement. Fractures and discontinuities are among the most influential factors in blast results, therefore one of the initial steps towards blast optimisation is to gather information about the rock mass and integrate it in blast design. This paper presents a method for assessment of rock mass discontinuities and integrating it in production blasts in the Aitik open pit copper mine in Sweden.3D photogrammetric techniques were utilised to map discontinuities and distinguish domains of similar geologic structures in the pit. As a pilot study for a future campaign, four different initiation directions were tested through six pilot blasts in one of the domains. The results were compared in terms of swell and loading efficiency of rope shovels to identify the correlation between blast performance and initiation direction compared to major discontinuity families.It was established that in the trial domain, blasts initiated towards north or north-west yielded larger swell and better performance of loading. Comparing these blasts with discontinuity families show that there is a correlation between blast performance and initiation direction according to the dip and strike of these discontinuities. Such knowledge can be used for future blasts in the same domain to increase long-term operational efficiency through slight modifications in drill pattern and initiation design.CITATION:Beyglou, A, Schunnesson, H, Johansson, D and Johansson, N, 2015. Adjusting initiation direction to domains of rock mass discontinuities in Aitik open pit mine, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 385–392 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By H Zhai, C Zhang, I Canbulat, K Yui

Sedimentary rock is a lithology that is commonly encountered in mining practices. Their properties, especially the resistance against weathering, are often of critical importance to long-term engineering stability due to their ubiquitous existence on the earth’s crust. The weathering of rocks is a complex process that involves physical degradation, chemical and biological erosions. In this study, the impact of physical weathering on four common sedimentary rocks, namely sandstone, siltstone, limestone and shale, are simulated in the laboratoryoratory environment taking into consideration the impact of preservation condition, temperature and time. In order to optimise the design of the experiment, Taguchi’s design of experiment method is implemented based on the L16 orthogonal array and selected simulation conditions. The weight and dimension variation, fracture intensity, slake durability, and uniaxial strengths of specimens are then tested to quantify the impact of weathering under various conditions. The results indicate that weathering significantly influences the strength of shale, siltstone and limestone but not sandstone. The impact of weathering on dimension variation is insignificant. For soft rocks, most physical weathering took place after second cycle of simulation, resulting in strength reduction up to 100 per cent (disintegration) but generally in a range from 28 per cent to 32 per cent. Additionally, time is the most important factor contributing to the physical weathering of weak rocks, followed by residual, preservation conditions and temperature. Last but not least, some shales, depending on the content of clay minerals, tend to develop significant fracturing or even disintegrate under the influence of weathering.

Nov 29, 2022

By A L. Stewart, M Baatar

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.The Middle Palaeozoic Gurvansaikhan Belt (Southern Mongolia) of the Central Asian Orogenic Belt is one of Central Asia’s most significant emerging porphyry copper provinces. The belt has become the focus of extensive exploration for porphyry copper-gold deposits over the last decade following the discovery of the giant Oyu Tolgoi porphyry copper-gold deposit. The Gurvansaikhan Belt is known to host porphyry deposits of Late Devonian (~370 Ma) and Early Carboniferous (~320 Ma) age. The characteristics of Early Carboniferous porphyry systems are poorly known compared to their older counterparts, despite their probable abundance and potential economic significance. Exploration within the Kharmagtai porphyry breccia complex has identified multiple cogenetic gold-copper-porphyry centres and late-stage mineralised magmatic-hydrothermal tourmaline breccias emplacement within a composite high-K calc-alkaline quartz monzodiorite intrusive complex. Early porphyry alteration and mineralisation at Kharmagtai are zoned around vertically attenuated early- and inter-mineral quartz monzodiorite dykes and stocks and comprises a complex sequence of calc-potassic, potassic and propylitic assemblages. Hematite dusting is a common alteration product that gives intrusions and the host rocks a distinctive pink-orange colour. Several of the systems have bornite-rich cores, where mineralisation is characterised by high gold grades (0.7 to >5 g/t Au) that zone outward to chalcopyrite-rich and then outer pyritic halos. Early stockwork mineralisation is overprinted by magmatic-hydrothermal tourmaline breccias. High-grade magmatic-hydrothermal tourmaline breccias form part of a major copper-gold mineralised breccia system with significant exploration potential. The Early Carboniferous porphyry copper-gold systems of the Gurvansaikhan Belt represent a substantial exploration challenge in an area of increasing exploration maturity. This paper summarises the characteristics of the Kharmagtai porphyry system that have helped to define the Early Carboniferous porphyry province of the Gurvansaikhan Belt and discusses implications for future exploration.CITATION:Stewart, A L and Baatar, M, 2015. The Kharmagtai porphyry breccia complex – characteristics of early Carboniferous porphyry mineralisation in the Gurvansaikhan Belt, Southern Mongolia, in Proceedings PACRIM 2015 Congress, pp 383–388 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By T Walton, C Perring, M Pepper, G Gerber

The Yandicoogina Channel Iron Deposit (CID) is an accumulation of iron pisolites cemented by a goethite-rich matrix. The Yandicoogina CID’s are found in a palaeochannel that meanders within a broad structural basin of the Yandicoogina Syncline in Pilbara region of Western Australia. RTIO Yandicoogina Mine Geology team contributed to a number of strategies maximising the iron ore reserves mined by Rio Tinto. Two strategies are discussed: the replacement of the Batter-Berm final pit walls by contour dozing; and upgrading the lower grade material to crusher feed. 1. Contour dozing – traditional Batter-Berm pit final wall configuration left kilometre long wedges of ore sterilised around bench margins. Contour dozing final walls (ie dozing of ore down the ore-waste contact) as internally defined by RTIO Yandicoogina Mine Geology (Mine Geology), enabled recovery of additional crusher feed. 2. Upgrade of lower grade material – the lower ore domain (GVL) within the Yandicoogina orebody contains numerous clay pods. Contaminant Al2O3 inherent within clay pods can result in CID material outside of crusher feed grade specifications, causing it to be flagged as ‘internal waste’ in mining models and permanently lost to waste dumps. In 2011, after multiple tests, Mine Geology demonstrated that this material could be upgraded to crusher feed via wet processing. With the support of the RTIO Metallurgical Development team new grade specifications were defined. The resulting material has been used to supplement higher grade ore. While increasing the mining ore output, these ongoing value-adding strategies also promote more sustainable mining via better use of the non-renewable iron ore commodity. The initiatives extend mine life, reduce waste movement, improve strip ratio and increase productivity

Mar 22, 2022

We outline a first version of an ambitious goal: The world's first horizontal (matrix-independent) generic sampling standard. The specific needs and requirements are overwhelming, as all the world's analytical standards follow strict matrix or material type classification pigeonholes, leading to a plethora of analytical standards. One could rightly expect a similar multiplication regarding sampling standards, yet the singular HORIZONTAL is aimed at being truly generic. Also the existing style of standards writing is cumbersome and partly contradictory. The current work is presently being pursued in CEN and European Union standardisation regimens, for which reason full disclosure and publication is not allowed. Respecting this constraint, we unofficially present selected key issues involved in developing HORIZONTAL: The objective and scope of a horizontal sampling standard is to delineate the minimum set of principles and procedures needed to guarantee documented representative sampling for all types of materials. The horizontal standard is designed for two types of use: 1. auditing/assessing/ improving the reliability of an existing sampling procedure, and 2. design and implementation of a new sampling procedure (new lot type). The principles in this standard are all derived from the Theory of Sampling (TOS), but the standard is far from a mere collection of TOS principles. Representativeness is a characteristic of the sampling process, not of samples themselves. For practical purposes, the horizontal standard follows the fundamental distinction between 'stationary lots' (0-D, 2-D, 3-D lots) and 'dynamic lots' (within TOS aka process sampling - including extended, non-moving 1-D lots). TOS' principles of 'correctness' must never be broken at any stage, lest representativeness is irretrievably lost. The horizontal standard is not written in the mandatory fashion for legally binding matrix-specific standards, eg ISO - for the present overarching purpose a different style had to be developed. The standard must be immediately understandable in full, which merits special demands, eg extensive use of didactic illustrations. HORIZONTAL introduces an all-inclusive sampling variability measure, Relative Sampling Variance (RSV) which is for sampling of stationary lots as variographics is for process sampling - RSV is to be used as a quality criterion for any stationary sampling procedure as applied to a specific heterogeneity (lot/material). The target for this standard is all individuals, companies, organisations and regulatory bodies who are responsible for sampling: technicians, process engineers, laboratory personal, academic and industrial scientists as well as project leaders, technical managers/directors and top managers. Based on current R&D we illustrate the principles promulgated by HORIZONTAL with cases from exploration and mining of minerals commodities, a Finnsh 'Autosampler' at work in the mining context (RSV) as well as sampling equipment for use in the cement and mineral commodities industries. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Mar 1, 2010

By Dhawan AK

On 8 July 1993, a landslide of about one million cubic metres of rock blocked the river Satluj near Sanjay Vidyut Pariyojana - Bhaba project and caused flooding into the Bhaba Power House (120 MW) resulting in suspension of power generation. The concerned authorities desired an early removal of the blockade by an underwater blasting operation into the over topping water to reduce the water level at the blockade and resume power generation in the power house. In the absence of underwater drilling, it was essential for the blasting technique to be used where no cavity to confine the explosive was required. For this reason mud capping and plaster shooting with directional throw were used and additional specially fabricated mild steel pipe charges were used under high current for an underwater trenching operation. By employing these techniques the river blockade was removed up to the required depth and on 8 September 1993 the Power House resumed the power generation.

Jan 1, 1995

By M Forbes, R Jeuken

Brownfields geoscience measurement such as drilling and surface geophysics can be costly and it is often difficult to weigh the cost of data collection and processing against the value it unlocks at the time of extraction. This makes it difficult to prioritise geoscience expenditure and find the optimum intensity of geoscience activity across competing assets. There are multiple options for managing resource uncertainty and spatial variability through mine planning and resource engineering such as varying marketing strategy, adjusting stockpile or other infrastructure design and product blending. Consideration of these alongside increased data collection further complicates finding a comparable value of geoscience programs to determine the right blend of geoscience measurement and engineering controls. Concepts similar to Value of Information (VOI) analysis which is applied to strategic planning can be used to estimate the value of geoscience measurement and pit sequencing at tactical planning and operational timescales. This involves the quantification of resource uncertainty and prediction of how it will affect resource extraction. This paper outlines this process and demonstrates its use to prioritise geoscience at BHP Coal Assets. The value of infill drill programs in enabling operational stability is quantified and compared the value of engineering controls like increased stockpile capacity. This study supports that idea that the application of VOI methods to bulk mining at tactical time horizons has potential to inform geoscience planning and resource engineering not just separately, but as part of a unified strategy for managing resource uncertainty.

Mar 22, 2022