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By K Williams, T Donohue, W Chen, T Roessler, A Katterfeld

Wet sticky iron ore poses particular difficulties in every aspect of the material handling process. Material hang-ups in bins, pipes and chutes; carry-back and spillage due to insufficient belt cleaning; clogging of screens; malfunctioning of crushers as well as rat holing of gravity reclaimed stockpiles are all predominantly due to the inherent cohesion and adhesion characteristics of the wet, sticky ore (Roberts, 1993). Limited understanding and quantitative measures on the stickiness of such a material significantly lower the mining operation efficiency.This research aims to investigate the cohesion and adhesion characteristics of the wet, sticky ore on physical modelling, experimental techniques and numerical implementation. Initially, the suitable bridging mechanism that contributes to the cohesive and adhesive forces within the iron ore material was identified (Hering, Martin and Stohrer, 1989; Rumpf, 1958). A cohesion/adhesion energy density factor based contact model was then introduced to describe the stickiness of the material. Secondly, an experimental system was proposed to directly test the stickiness of the material. Such a system is able to obtain both the cohesive/adhesive shear force and tensile force of the material at a specific moisture content. Lastly, the implementation of the proposed cohesion/adhesion model into the discrete element modelling (DEM) software was also discussed. A cohesion/adhesion calibration for modelling wet sticky iron ore in DEM was then conducted to ensure the material modelled in the simulation is reflective of the reality.From the study, understanding of the cohesion/adhesion characteristics of the wet iron ore material is significantly enhanced. Experimental and numerical outcomes can be directly applied for better designing or optimising the material handling processes that involve wet sticky iron ore. Consequently, the mining operating costs can be greatly reduced.CITATION:Chen, W, Donohue, T, Williams, K, Katterfeld, A and Roessler, T, 2015. Modelling cohesion and adhesion of wet, sticky iron ores in discrete element modelling for material handling processes, in Proceedings Iron Ore 2015, pp 387–392 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

The Mt Keith Mining Alliance operates a fleet of large capacity hydraulic face shovels and more than 40 X 240 t capacity haul trucks to deliver annual production in excess of 40 Mbcm per annum. The Mt Keith Nickel mine is currently operating at a depth to 300 m below surface with a planned final depth of the order of 500 m. As is the case with any large open pit managing the health of the workforce on continuous shift operations is of critical importance to achieving outstanding safety and production outcomes. Fatigue management at Mt Keith is effectively managed by the personnel operating the mining equipment, with assistance and understanding of the management team and supervisors. The program has been driven through the introduction of Fatigue Champions and a comprehensive management plan that includes education, individual health plans and the use of new technologies. Mt Keith has been instrumental in trialling new technology which assists in monitoring fatigue in operations personnel. Insight into these developments is provided in the context of the overall fatigue management plan. The field trials of the OptAlert(TM) system and how it assists in measuring fatigue is explained. The implications for individual operators and the context for a fleet wide approach to fatigue management is also discussed. Mt Keith has recently completed the second phase of trials with the result that this new and exciting technology is being considered for adoption globally across BHP BillitonÆs open pit mining operations.

Jan 1, 2007

By D Woolmer

Since January 2019, BHP Olympic Dam have been trialling the use of a drone based LiDAR mapping system for the purpose for surveying stope voids. This new technology utilises Simultaneous Location and Mapping (SLAM) algorithm providing positioning, stability and collision avoidance in GPS denied environments. Implementation of this system utilised underground personnel trained in the equipment’s use. The study’s intention was to evaluate the effectiveness of this equipment versus traditional surveying methods in regards to quality, safety and productivity. The trial results showed a marked improvement in the quality, productivity and personnel safety when conducting surveys. The use of the drone and LiDAR system reduced personnel and equipment requirements for surveys, thus allowing these resources to be deployed elsewhere. The technology’s simple and rapid deployment allowed multiple surveys to be conducted during a 12 hour shift, including ad-hoc work with minimal disruption to underground operations. After the drone’s initial trial, further work was conducted to utilise the Hovermap LiDAR scanner on other platforms to increase utilisation. A mounting system was created allowing the LiDAR to be mounted on a remotely operated loader or vehicle. This enabled drawpoint scans to be taken directly after production completion, resulting in faster stope close outs and drive scans for convergence monitoring. Implementation of the LiDAR system has resulted in improvements in the stope production cycle by reducing delays previously associated with data capture. The increase in the volume and quality of data has also allowed in-depth back-analysis of stopes in new mining areas to be conducted, which have driven improvements in the design process.

Mar 15, 2021

By R Hargreaves, T Elkington, W J. Shaw, G W. Booth

Every day, around the world, thousands of tons of ore are loaded onto ships completing the miningproduction process and starting a multimillion-dollar economic transactions process. These transactions are based on the supply of tons of a commodity with certain specifications of assays of the main element (or physical properties) and concentration of contaminants, which are finally verified and evaluated by buyers, and also are considered ‘as true’ during Reconciliation process. On Sample Stations, this ‘true’ is based on a few kilograms of sample, often representing thousands of tons, that are sent to laboratories for further sample preparation and chemical analysis, where finally assay information is obtained from a few grams of pulverised sample, and are used for further production, planning, operational and financial-marketing decisions. Different International Standards (depending on the commodity) are used to establish the methodology to be followed, to set-up and obtain samples from the Sample Stations, and the specifications are visually inspected to give an estimation on the performance of the sampling point. This paper seeks to highlight with examples, the importance of the implementation of a continuously monitored Quality Program (QAQC and QM) on Sample Stations, focused on the parameters that directly affect the quality and representativeness of the samples. By this implementation, a proactive approach and better-informed decisions can be taken for mining companies to: a) quantify/improve production and reconciliation results, and b) to supply the right specifications of shipped ore, increasing the value of the Resources. Finally, laboratory results are normally used as an indication of the quality of the information applied for the economic transaction, but it should be considered, clarified and highlighted that the laboratory will only process and analyse a sample obtained from a Sample Station, and potential problems on bias or precision may occur in stages prior to the laboratory reception. Hence the importance of the implementation of a quality assurance program that protects multi-million dollar decisions.

Mar 22, 2022

By P Viljoen, A Holland, C Parken

In the raisebore industry, there are two known methods of removing large diameter reamer heads once the reaming of an underground shaft is complete: 1. Lower the reamer head to the base of the shaft and use a thermal lance to cut the drill string and drag the reamer away from the hole. This method exposes the person doing the job to falling rocks from the unsupported mineshaft, a hazard which is difficult to control and has caused fatalities. 2. Install breast plates in the backs above the reamer head at the top of the hole, and use air hoists to lift the reamer out of the hole. Steel beams are then placed across the hole which the reamer is lowered down onto, dragged forward away from the hole, disassembled, and removed. This method is time consuming, expensive, and complex in the controls required to ensure safe completion of the job At Carrapateena, the air hoist method had been successfully used, however, with the cost involved and the complexity of this process, development of an improved and fit for purpose reamer removal method was pursued. OZ Minerals collaborated with Pybar to develop an industry first application of Enerpac SL100 lift and shift technology; a track mounted system with hydraulic lifting units that can both lift the reamer out of the hole and tram it back along the tracks away from the hole. A key component of turning the idea into a reality was by establishing a truly collaborative relationship between client and contractor. When the SL100 mobile gantry arrived, it was set up in Adelaide and trialled with the whole raise bore crew attending the two-day workshop and risk assessment; a rare opportunity for drillers. There have now been five successful reamer removals with the SL100 mobile gantry at Carrapateena. It has proven to be an efficient process with the entire process from setup to demobilisation taking less than 48 hours. This new way has completely removed hot works and uncontrolled hazards from working at the bottom of a shaft. It has also saved the reamer stabiliser from being cut and thus wasted. Exposure to the open hole has been minimised significantly as assembly of the SL100 is completed well forward of the open hole. This new process is exponentially safer, quicker and cheaper.

Mar 15, 2021

By I Minniakhmetov, J Ashford

Orebodies constitute naturally occurring, commonly highly variable concentrations of minerals in the earth’s crust formed through varying and highly unpredictable processes. Orebody knowledge is a core foundation of a mining company’s asset base underpinning all decisions about Mineral Resource and Ore Reserves, future production, development and ultimately the profitability and competitiveness of a mining enterprise. The decision to invest in a mineral project is usually based upon a techno-economic evaluation of the project and having clear approval pathways to gain local community support and address social and environmental impacts. The main objective of the techno-economic evaluation is to determine the optimum development sequence for the particular orebody in question and to estimate the economic viability of the project and the future return on investment to its stakeholders, balancing the inherent value of the mineral in the ground against the costs of development and market pricing. With the exception of market-driven commodity prices, virtually all revenue and cost estimates fundamentally stem from the understanding and subsequent modelling of the orebody. A reliable estimate of the ore deposit grade and other geological value-drivers is the foundation upon which the business case for future mine development and operation is intricately dependent. Orebody knowledge is, therefore, the fundamental driver of the mineral project cycle, influencing the progression of studies and consequently, the resource company’s ability to declare Exploration Results, Mineral Resources or Ore Reserves which govern the source and cost of funding available to the project. Drilling provides a ‘vector’ to the true nature of the orebody and effectively buys time to manage the technical risk associated with the orebody. Despite its perceived high cost, in both time and money terms, drilling is the only available technology for acquiring the necessary orebody knowledge to support technical and economic studies and to minimise orebody-driven cash flow uncertainty and volatility. However, like all costs, pressure to minimise drilling budgets is ubiquitous across the minerals industry. Paired with inappropriate key performance indicators, drilling is often regarded as a cost to be minimised, rather than an investment to be optimised. Furthermore, as future deposits get deeper and more complex, the collection of orebody knowledge is increasingly on the critical path for project development. The increasing cost of data collection pertaining to these deposits increases the temptation to minimise orebody knowledge gathering at the cost of long-term value as the reduction or postponement of drilling results in greater orebody knowledge risk at all stages of the value chain. Indeed the true cost of the decision to drill less is rarely known until the mine is in operation, well after the mine project evaluation team has moved on. This paper aims to promote orebody knowledge as the fundamental source of endogenous project financial risk and, consequently, its critical importance in project financial evaluation. Furthermore, the report documents experimental research into the development of an econometric model for valuing orebody knowledge. Using the density of drilling data as a proxy measure of orebody knowledge, the proposed approach integrates well-established stochastic grade modelling techniques with the mathematical mechanics of Decoupled Net Present Value (DNPV) which, combined with stochastic grade modelling (conditional simulation), lends itself to the financial International Mining Geology Conference 2022 | Brisbane, Australia and Online | 22–23 March 2022 3 assessment of orebody knowledge risk. Based on this approach, a metric is formulated, representing the minimum value of the orebody knowledge added by additional drilling

Mar 22, 2022

By J Heyes, R Getty, M Sanapala

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

Sep 18, 2023

By C Buchanan

For a long time there has been a known relationship between the northern Heavy Mineral (HM) deposits of the Murray Basin to the extensive north east trending ridges in the area. These ridges have been a targeting tool for exploration and have uncovered some significant discoveries, some of which have turned into mining projects. Bemax’s Ginkgo and Snapper deposits are good examples of how the faulting helped create an economic deposit but also result in significant planning issues in the exploitation of these deposits. Material balance, induration and pyrite issues have been made easier to manage through good geological understanding of the deposits.

Aug 22, 2011

By S C. Dominy

The grade of ore at Marvel Loch mine is directly related to the presence or absence of shear zones and quartz-sulfide-rich hornblende (¦ diopside) veining within areas of plagioclase alteration. An experienced geologist can identify these features in hand specimen. Practical rules have been developed to assist this visual identification. The structural sites and styles of alteration and veining most conducive to gold mineralisation have also been determined. The work has enabled a better understanding of the geological controls on mineralisation at Marvel Loch, and has clarified geological understanding for optimisation of grade control modeling, ore block mark-ups, and minimisation of ore loss and dilution during excavation. In addition to this, it has enabled a detailed understanding of mine scale structural controls, geometry and relative grade relationships.

Jan 1, 2003

By C Ross

This paper uses the results of research trials by Landcare Research and Forest Research Institute and assessments of reclamation plantings at mines and other drastically disturbed sites to describe methods of enhancing restoration of native forests. The characteristics of mine and forest environments are compared to highlight the difficulties facing restoration and techniques which result in successful restoration are described. Selection of the most appropriate technique is illustrated by describing restoration of lowland beech-podocarp forest at a West Coast coal mine. The key to successful reclamation is to understand the factors controlling and limiting plant establishment and growth, then to design rooting media, surfaces and management regimes to create a favourable environment. This paper concludes with a summary of the planning and technical factors which are critical for successful restoration of native forest.

Jan 1, 1995

This paper describes techniques that have been used at RixÆs Creek Colliery to control blast vibration from throwblasts that face a residential area 4 km in front of the face. The paper describes blast design, face control including laser profiling, selective loading of blastholes after borehole camera surveys, and techniques used to assess the effect of burden variation, the cumulative effect of drilling and delay sequence, and the effects of meteorology.

Jan 1, 2001

By C P. C David, J P. T Domingo

Addressing nutrient deficiency, among other factors, is vital to the growth and establishment of plants in mine spoils and tailings ponds. Although several organic amendments are available for this purpose, it is important to determine the appropriate ameliorant for the selected plant species. This research examined the effect of different amendments on the growth and ground cover of Centrosema molle, Calopogonium mucunoides and Sorghum spp. in copper/gold tailings. Plant growth and ground cover drastically increased with the application of organic ameliorants, especially manure. Among the three plants, Calopogonium exhibited the best growth and has shown its capability to establish a dense ground cover even in unamended tailings. Results suggest that the plant species and the ameliorants used in this study could be effective in a low-input approach to mine rehabilitation.CITATION:Domingo, J P T and David, C P C, 2014. Legume and grass revegetation of mine tailings, in Proceedings Life-of-Mine 2014 , pp 525–534 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By A B. Bayooke, A C. Robertson

In terms of underground tunnelling in metres advance per capita, Australasia compares well with the best world performers. This is because of the large number of metalliferous mines, coalmines and civil tunnelling projects, with the Australian tunnel advance for civil and mining projects exceeding 625?km/a. In terms of hard rock quarry extraction, Australia produces approximately 200?Mt/a of aggregates, roadbase, fill material and specialist rock products from its quarries, which equates to approximately 8?t/capita. Australian mining and tunnelling contractors are also of world standard and are used to excavating in a variable range of ground conditions in a competitive environment. One author has been involved in tunnel and underground space planning and quarrying in Australia for the past 25 years and predicts that, over the next 20 years, there will be a major swing towards underground space for commercial uses. This paper identifies the potential uses of underground commercial excavation and the planning and geotechnical challenges for the future. Underground quarrying creates new opportunities to extend existing quarries within their urban footprint with minimum impact on the surrounding community. Investigations by the authors reveal that there are very few cities in the world that actually incorporate underground space planning in their city plans. However, cities such as Helsinki have been planned in detail to utilise the rock resources beneath them. Brisbane is used as a case study for a practical application of commercial underground space and underground quarrying in Australia.CITATION:Bayooke, A B and Robertson, A C, 2014. Geotechnical challenges for underground commercial space and quarrying in Australia, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 317–322 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

Cannington Mine is an underground, hard rock, metalliferous mine located in North-Western Queensland, Australia. Weld mesh is installed to prevent the failure of rock from between the installed reinforcement elements. Corrosion reduces the capacity and life expectancy of mesh and presents a real hazard to underground personnel and equipment as it reduces the effectiveness of the support system. Corrosion influences the economics of the mining operation through the need to conduct rehabilitation of the ground support which involves re-installing new mesh or shotcreting over the affected mesh to protect it from further corrosion. The requirement for rehabilitation is determined by the geotechnical engineer based on an individual visual assessment with little or no engineering input. It was identified that a more quantitative method was required that considered the safety and economic risks involved. A project was undertaken to develop a simple method to evaluate corroded mesh and to provide selection criteria for rehabilitation. A weld mesh corrosion classification has been developed that relates the average wire diameter of corroded mesh to the remaining capacity of the mesh. Accompanying selection criteria provides recommendations as to when rehabilitation may be required based on the estimated residual mesh capacity, the remaining development life, and the level of personnel exposure.

Nov 25, 2010

By J H. J Holtzhausen

Never has there been more focus on the health, safety, and well-being of our employees at the workplace. Ever evolving expectations of individuals, companies and clients are shaping regulatory reviews and advancing standards across the world in the drive to zero harm. The technology is advancing at a rapid pace, which is now allowing continuous real-time monitoring of contaminants to take place in the harshest of environments.

Oct 12, 2022

By J Penman, N Turner, H Liu

This paper aims to present a snapshot of the risk profile for tailings storage facilities within Western Australia by comparing the spatial distribution of known facilities against common geohazards such as cyclonic activity, climate, and peak ground accelerations from earthquakes. The analysis also includes an assessment of proximity to populations at risk including towns and sensitive receptors including significant river systems and wetlands.

Jul 1, 2021

By R Blin, R Walde, R Belli, D Inaudi

A fiber optic distributed sensing system allows the monitoring of parameters useful to determine the short- and long-term behaviour of the structure in response to the external actions, including, eg seismic activities as well as long-term phenomena such as seepage, tunneling, sinkholes, and other geo-structural movements. Monitoring of large retaining structures with such a system provides direct strain/deformation and temperature measurements on the broad interior area with an arrangement of several sensing cable lines, enabling early detection, localisation and sizing of subsurface damages. Measurements are provided every meter along the entire sensing cable, this is particularly important in such cases where the location of defects and damages cannot be predicted. Fiber optic distributed sensing cables are generally available for retrofit installation inside the dam structure using trenches on the downstream face or laid during construction below the geomembrane liner within the bedding sand layer. Mapping the cable route enables exact correlation between a linear coordinate on the cable length and a position in the dam. Cable installation is envisaged to be carried out during further raising of the embankment; additional cable sections are plugged to the previously installed cables and measured with the existing measurement system, requiring only an update of the mapping. The measurement system is placed remotely from the sensing area since a section of sensing cable can be used to link to the sensing area at the storage facility several kilometers away. The system is available for on-line, 24/7 real-time operational data management. Such fiber optic distributed sensing systems allow storage facilities to be monitored with long, accurate, continuous and precise data for geotechnical diagnostic purposes. This contribution will introduce the principles, benefits, and limitations of this technology.

Jul 1, 2021

By G Neely

COPING WITH COMPLEXITY In every industry, and mining is no exception, plant and processes increase in complexity over time and managers and operators need correspondingly more knowledge. The mine manager has to delegate details to operators, engineers, metallurgists, accountants, safety specialists, personnel officers and the rest. Is it reasonable then, to expect the Mines Inspector to be competent to judge the conduct of all these operations against the criterion of the regulations? Obviously not, but what are the alternatives? One is a superficial inspection where the inspector goes on a hazard hunt for broken steps and missing handrails. Another is one in which an army of specialist inspectors marches on a mine, sometimes outnumbering the staff. Each is competent to assess some part of the operation and if he or she can find an opposite number among the mine staff, they can discuss details. But what good does it achieve? The system acts to remedy present defects and to make recommendations which, if only they were followed, would prevent the same things happening again. Given that this process has been going on since the first Factory Act of about 1840, how is it that there are any more defects left to put right? The answer of course is that defects keep appearing, and new defects arise as fast as the old ones are found and corrected. Further progress can only be made by preventing defects at their source.

Jan 1, 1994

By M Berry

Many mining companies routinely use benchmarking to review their operational activities and associated costs. The aim is to measure operational performance against industry norms, and identify areas where a company is performing better or worse than industry best practice. The goal is continuous improvement.In general, mine technical services, including mining geology activities, are not routinely benchmarked. There are exceptions, such as the cost of drilling per metre and the average discovery cost per unit of metal, but generally mining geology activities are only included indirectly in mining benchmarking studies.Aspects of benchmarking can play a critical role in assisting mining geologists to improve the efficiency and effectiveness of the services they provide. Industry norms for many generic mining geology functions have not been developed and measured, and therefore it is impossible to use external benchmarking to assess performance against other mines. But when used in parallel with quantifying the value of mining geology functions and establishing strategic goals for the team, key components of benchmarking methodology can provide essential feedback on how a team is performing against these strategic goals.CITATION:Berry, M, 2014. Benchmarking – does it have a role in improving the performance of mining geology?, in Proceedings Ninth International Mining Geology Conference 2014 , pp 361–366 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By C te Kloot, Z Liu

Blast performance and the resulting drawpoint condition and volume of oversize has the potential to impact operator safety and mine productivity. Underground measurements showed that approximately 14 per cent of production rings in the Ernest Henry Mine (EHM) sublevel caving (SLC) operation had either overbreak in the brow or left collars. There were also oversize rocks reporting to approximately 30 per cent of drawpoints, which accounted for over 7 per cent of total production and significantly impacted production rates. A series of trials were conducted in 2015–2016 at EHM to test changes to certain charge parameters in an attempt to optimise blasting results and, in particular, reduce oversize and overbreak. The detailed analysis conducted included field observations, hole surveying, blast monitor analysis and blast modelling. There were a total of nine charge parameters tested in the project, which fell into two major categories: energy distribution and inter-hole delay. These were based on observations made in establishing baseline data and those parameters most likely to have a significant impact on overbreak and oversize.Key results from the project included oversize reduction and improved brow conditions when energy distribution was reduced through changing charge lengths in certain holes in the standard charge plan. Similar benefits were also seen when the inter-hole delay between blastholes was reduced from 50 ms to 25 ms. Based on these results both changes were made to the standard production ring charge plan at EHM.Moving forward, the aim is to continue monitoring the results from the changes made on all levels to ensure efficiencies are being realised and sustained. A 3 per cent improvement in oversize as a percentage of total tonnes and improved brow conditions not only has a positive impact on production rates, but removes people from any potentially hazardous situations and contributes to a safer working environment.CITATION:te Kloot, C and Liu, Z, 2017. The evolution of production blasts at Ernest Henry Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 33–38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017