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By G L. Boyd

Backfill applied to highwall mining is foreseen as a means to increase recovery of mineable coal to levels comparable with underground longwall mining. This paper describes the progress of research to demonstrate the role required of backfill to achieve real increases in coal recovered by highwall mining methods.

Jan 1, 1998

By O J. Restrepo Baena, S Nowosad, R Webber-Youngman, N Mojtabai, P Foster, A Binder, S Hazuria, erson, S Raval, L Liu

As the mining industry faces times of change, new challenges arise to ensure raw material supply for the younger and future generations. Different scenarios are currently shaping the way we mine and teach mining engineering. Led by an increasing demand for raw materials, net zero requirements for improving long-term operation performance, technological advancements such as automation and digitalisation, safety improvements, environmental considerations and a need for social acceptance, mining is pursuing to change and adapt to these requirements at a faster pace. Such changing times raise new concerns, one of the most relevant is the lower number of students interested or enrolling in mining engineering and related fields leaving mining engineering as one of the less preferred career options between the younger generations. Nonetheless, it is essential to continue addressing and supplying the skill sets that is suited to contemporary and future of the mining industry. To this end, globally, academia is currently undergoing several initiatives such as curricula updates and adaptation, up skilling, improving teaching practices and techniques, including e-learning techniques, enhancing industry-academia and inter-university collaboration, and much more

Sep 1, 2024

By Thatcher R

In areas where undeveloped land represents a scarce resource, an upgraded post mining land use can result in economic benefits to both the mining company and to the community. A study undertaken at Allied Queensland Coalfields Ltd's Aberdare Colliery located between Brisbane and Ipswich during 1986/1987, assessed the costs and benefits of developing the site following mining for grazing, forestry and residential uses. The proposed final land use plan comprised a combination of these uses which can be upgraded to higher valued uses once subsidence monitoring of backfilled opencut areas and dumps indicates that total settlement has reached acceptable levels. The study involved the documentation of existing site environmental parameters and the delineation of site opportunities and constraints. The unpredictable nature of settlement over backfilled opencuts and overburden dumps represents the major constraint to urban development on mined areas.

Jan 1, 1987

By P Lukic

The definition of the working sections that will be used in a mine is usually initially made in the field by the geologist supervising the drilling program. These initial definitions are often made on the basis of rules of thumb such as æcoal less than 30 cm thick cannot be mined separatelyÆ; æpartings more than 30 cm thick will be mined separatelyÆ; and æif a coal seam is less than 50 cm thick and the parting above or below is thicker than the coal, the coal will be wastedÆ. These decisions are also often made based on the requirement for a minimum sample mass for analysis, and the desire to collect data at the minimum resolution to conserve the exploration budget.In many cases the geological models based on this data are produced at a resolution that is inadequate to allow the mining engineer to produce a mine plan that will maximise project value. This problem is generally unrecognised.Where data is collected to a higher level of resolution the subsequent processes employed in the production of geological models and mine plans often discards the inherent value that is hidden in this data. Again this problem is generally unrecognised.This paper highlights this problem and then presents a methodology that ensures that the optimal working section is selected and compares the outcomes of applying this methodology versus adherence to the usual rules of thumb.

Sep 26, 2011

Modern minerals projects face serious challenges in earning and maintaining acceptance by their key stakeholders. Factors which underpin effective response to managing these challenges include consideration of public affairs issues from the earliest planning stages, building robust alliances with a range of influential partners, developing a level of transparency in all operations and decision-making and integrating activities towards resolving key strategic issues. Effective community relations is vital and there are a number of elements common to the best approaches. These include senior management support and involvement, appropriate involvement in project decisions and activities by community members and company responsiveness to community expectations. The project's operations manager and executive team must fully commit to developing the capability and processes to meet these challenges. They require a whole of project response and it is not an option to manage them peripherally.

Jan 1, 1997

By F Jullian, L Jofre

Many maintenance managers find it difficult to justify investments in maintenance improvement initiatives. In part, this is due to a tendency by mine managers to regard maintenance purely as a cost centre, and not as a process able to influence productive capacity and profit. It is also hindered by a lack of alignment between commonly used maintenance performance measures and key business drivers, and the lack of formal business training amongst maintenance professionals. With this in mind, a model to assist maintenance managers in evaluating the benefits of maintenance improvement projects was recently formulated. The model considers four cost saving dimensions. These are: 1. reduction in the cost of unplanned repairs and maintenance,2. increased or accelerated production and/or sales,3. spares inventory reduction, and4. reduction in over-investment in physical assets and operating costs. This paper discusses the application of this model and a number of numerical examples are given to justify investments in maintenance improvement projects having varying objectives.

Jan 1, 2006

By Wright G. N

Curragh Queensland Mining Limited, a co-venture of Australian and overseas interests, operates an open cut coal mine 13 km north of the township of Blackwater in Central Queensland, refer attached location map.

Jan 1, 1992

Traditionally, the predominant drilling method in open pit mining has been large hole rotary drilling using cumbersome, inflexible equipment offering merely limited scope for improvements in pit design and overall costs. By contrast, the recent development of comparatively light high-pressure down-the-hole hammer crawlers has paved the way for new ideas and trends. High penetration rates coupled with superior mobility and fast set-ups contributing to substantial productivity gains have resulted in a renascence for this drilling method in open pits. The ability to cover a wide range of hole diameters and angles gives designers unique drill pattern possibilities especially when establishing steep and stable pit slopes. As pre-split holes, buffer holes and production holes all can be drilled by using the same equipment, there are, there are obvious advantages in production scheduling as well as in materials handling and service. This paper presents some case stories, which will demonstrate the benefits and improvements that the introduction of new drilling methods and equipment has brought to open pit mining operations.

Jan 1, 2003

By Hedley TP

Success for underground coal mine operators in the 1990's and beyond will be dependent upon better understanding of the dynamics of their operating environment, and extension of emerging technologies to reach new levels of output and productivity. The Collieries Division of B.H.P. Steel International Group clearly identifies with the concept of business/product life cycles - and the need to adopt strategies that can drive the business successfully into the future. Three main thrusts within BHP Collieries Division relate to: 1) Detailed assessment of current mines to determine: a) The real output potential of the current facilities. b) What factors now inhibit the full potential from being realised. c) Opportunities that exist to enhance overall mine performance. 2) Based upon the findings of these studies, putting into place cost effective strategies and systems for the ongoing "tuning" of the mine. 3) of new/improved technology primarily in areas of: a) Coal cutting and underground coal clearance. b) Controlling the overall mine gas Regime.

Jan 1, 1987

Ventilation challenges are often encountered when an underground mine expands to new zones and it often is the case to make a thorough review of the existing system and assess immediate and future airflow needs at the desired quantity and quality. An unexpected mine plan change that calls for increased development and production from new areas can impose a strain on the existing ventilation system. Budgetary constraints can also demand creativity in design on the mine ventilation engineerÆs part. Since the addition of several mining horizons it had become obvious at the Meikle mine that something had to be done to increase airflow quantity and quality in the old main zones because most of the ventilation resources had been channelled for development in the new mining horizons. An airflow assessment of the existing system had to be performed and it was determined that the airflow quantity had to be increased by at least 30 per cent and the quality of the air had to be improved by reducing nuisance and respirable dust and at the same time reducing the airflow temperature before it was used in a few mining zones. At the conclusion of the airflow assessment it was determined that a third centrifugal fan would be installed on a new 3.05 m diameter borehole from surface to underground. By a careful study of temperature conditions over time it was determined that an evaporative cooling spray chamber would be sufficient to cool the airflow down from the high dry bulb temperatures observed down to saturation at the wet bulb temperature. At the same time excessive nuisance dust generated as a result of the airflow travelling a long way in a haulage drift will be knocked down in the spray chamber resulting in cool, clean air in the mining districts. Expansion of the existing surface ammonia refrigeration plant was out of the question for several reasons. The fact that the airflow was hot and dry meant that evaporative cooling spray chambers could achieve lower working temperatures at a very low cost compared to the expansion of the chilled water plant. The expansion of the ventilation system at Meikle mine and the use of evaporative cooling spray chambers were demonstrated to be very successful and the information presented in this paper can be of benefit to other mines experiencing the same ventilation problems as was the case at the Meikle mine.

Jan 1, 2005

There is little doubt that the vision (Spectre) of Voisey's Bay has completely spooked the Northern Hemisphere view on nickel to the exclusion of considering any other future nickel project. Voisey's Bay orebody is of world-class and will influence world nickel and cobalt supply for a very long time - but - has the world yet started to consider the enormous cost of acquisition and development of this find or the nickel price it will need to attract to cover these costs and its operating costs and keep its bankers and shareholders happy. That price will be the critical factor in determining Voisey's effect on world nickel and will be critical in ranking other new projects aimed at making up the nickel short fall created by the on-going demand for austenitic stainless steel. In my view, there is little doubt that some if not most of these `other' new projects will be developed in the South West Pacific from lateritic Resources.

Jan 1, 1996

The optimum plant capacity for a new mine is usually based on empirical studies or ærules of thumbÆ, subject to confirmation by detailed scheduling of the proposed mining operation. The mining industry has a record of poor returns on investment and a high rate of project failure using these methods, with under-performance in grade being a common experience. The assumption that æeconomies of scaleÆ will result from increasing throughput rates needs to be balanced by an awareness of the adverse effects of increasing the rate beyond a level that issupportable by the resource. For each scale of operation considered, it is a reality that for any intended head grade, at the associated intended cut-off grade, the actual head grade achieved will fall as the mining rate increases. This effect is known to people at operations but is not recognised in current ore reserve estimation methodology. Once recognised, this dependency of head grade on mining rate can be quantified and used to establish the economically optimum mining and processing rate for a new project. A simple analysis is proposed, which may be extended to detailed spreadsheet modelling for financialoptimisation.

Jan 1, 2002

By Houtgraaf M

The Far Fanning gold deposit is situated 60 kilometres south-west of Townsville (Fig. 1). Previous recorded production is 3756 tonnes returning about 1600 ounces of gold. This has been taken from surface and shallow underground workings- scattered over the strike length of the deposit of 1700 metres. The main production period was from 1895 to 1908.Previous exploration involving extensive trenching and sampling has been: carried out intermittently. since the 1930's, by Gold Mines of Australia (1932), Placer (1974), Anaconda (1975), Marathon (1980-8-1), Aberfoyle (1981-82), and The Northern Queensland Company (NQC) (1983-present).In 1980 Marathon undertook an extensive drilling programme to test the oxidised mineralisation. Over 200 percussion holes and- 7 diamond holes were drilled along traverse lines spaced 29 to 103 metres apart covering a strike length of around 1800 metres.

Jan 1, 1986

Acupan is considered to be an intrusive centre as several igneous phases have been emplaced in the vicinity of the mine over the past 8 Ma. They include the Lucbuban gabbro, Virac granodiorite, Ampucao dacite porphyry (ADP), Hartwell plug, Itogon plug and the multi-phase Balatoc diatreme. These intrusives have high-K calc-alkaline affinities and are grouped together as the Virac Complex.Porphyry-style mineralisation formed during the final crystallization of the ADP in the late Pliocene, with the deposition of two vein stages from high-temperature hypersaline magmatic-hydrothermal fluids. K-silicate alteration halos surround the first stage of veinlets (stage I); they are surrounded in turn by a propylitic assemblage. White sericite and/or intense propylitic halos envelop the second stage of veinlets (stage II) and grade into a weak nrnnvlitir accPmht o

Jan 1, 1990

Various aspects of the history of mining at The Zinc Corporation, Limited (ZC) and New Broken Hill Consolidated Limited (NHHC) are examined. There are some discussions about the various methods used to mine the pillars left after the primary mining operations, with an enphasis being placed on the more modern pillar mining methods. Some new pillar mining proposals are presented. INTRODUCTION In the past, pillar reserves at ZC/NBHC have been scheduled for mining by labour intensive and high unit cost mining methods. These methods include both undercut and fill and overhand square set timber stoping. Recent technological advances in large diameter longhole drilling and high charge density explosives have culminated in the mechanised Vertical Crater Retreat (VCR) mining method and this method has been successfully used for the extraction of two pillars at NBHC and more stopes are planned. However the use of VCR methods for mining pillars at ZC/NBHC is restricted to approximately 50 per cent of the total pillar reserves and it appears that high cost methods will be needed to mine the remaining Pillars.

Jan 1, 1983

By Ritter K-C, Sturgul J. R, Filess T

The proposed Lihir open pit gold mine is located on Lihir Island in New Ireland Province, Papua New Guinea. The mine will be located within a volcanic caldera, part of which forms the adjacent Luise Harbour. Kennecott Corporation started engineering design work in 1988 and ended in 1993 when a Feasibility Report was submitted to the Papua New Guinea government by RTZ/Kennecott. The project will be managed by the Lihir Management Company. The mining operation will produce approximately 350 Mt of waste and 62 Mt of low-grade ore over the life of open pit mining. Landforms and traditional land use by Lihirians preclude storing mine waste and some of the low-grade ore on land close to the mine site. The mine waste will be composed of hard rock and soft soild like material which cannot be safely used to construct large land waste repositories by truck dumping. Submarine disposal by bottom discharging barges is the only safe disposal method. The barges will also be required to construct a waste platform along the shore for stockpiling low-grade ore. A simulation model of the waste handling system was written in GPSS/H¦ to assist engineers in selecting the optimum size and quantity of barges and loading docks by analysing the interaction between excavators, trucks and barges. The simulation model was written in enough details to model the various functions that will be encountered during mining. Input parameters allowed for variations in the size and number of trucks, shovels, barges and loading docks. Variations in loading, hauling, and dumping times were from user specified distributions. In order to visualise the interaction between the components of the waste mining operation, the simulation was animated using Proof AnimationT""'. It is believed that this is the first application of an animated simulation study for a mine still in the planning stages.

Jan 1, 1995

By K Guilfoyle

AngloGold Ashanti Australia Ltd operates an underground mine below a large open pit at the Sunrise Dam Gold Mine near Laverton in Western Australia. Operations are based on an extensive mineralised zone which has very complex geometry, has a high ‘nugget effect’, and is difficult to interpret and model. Initial underground ore was produced from relatively narrow orebodies dipping from 15º - 70º. Open stopes aimed to selectively extract high-grade ore, using methods including jumbo stripping and longhole drilling and blasting. The complex geology makes it difficult to accurately locate development and stopes in the positions required for profitable production. In narrow stopes, rock mass damage and overbreak dilute ore grades and increase the cost per ounce of gold poured. In flat orebodies, several different techniques have been used to recover blasted ore but overall productivity is low. Thus selective mining can also be slow, costly and recovers only a portion of the available mineral resources. Large longhole open stopes with cemented paste backfill are used to extract multiple zones of mineralisation from the Cosmo and GQ orebodies. Bulk emulsion explosives and electronic detonators are used in all large stope blasts to reduce the risk of misfires and to accurately control blasthole initiation sequences and delay timing. Larger stopes improve productivity and significantly reduce direct mining costs, enabling the use of lower economic cut-off grades which increase the overall recovery of mineral resources. This paper reviews the evolution of open stoping at Sunrise Dam, the various mining methods and drilling and blasting practices used, the results achieved, and the lessons learned.

Nov 8, 2011

By S F. Rogers, P W. Booth

Digital photogrammetry is revolutionising the task of geotechnical mapping of jointed rock masses and has greatly increased in popularity and sophistication in recent years. Modern commercially available digital photogrammetry software systems can provide geotechnical practitioners with a user friendly tool for rapid data acquisition. The data can be acquired remotely from large exposure areas, some of which may be otherwise out of reach due to restrictions on time, access or safety.Photogrammetry is a complimentary technology to discrete fracture network (DFN) modelling because it can provide the large, statistically significant, spatially located geotechnical data sets required to produce the most robust results. It also provides the flexibility to selectively map structures at a range of scales, depending on the focus of the DFN modelling.Integration of the interpreted rock structure data derived from photogrammetry with modern DFN modelling methods really advances the rock engineering process. The ability to generate 3D fracture models driven by the statistical structural data and conditioned to the features observed by the photogrammetry yields a synthetic rock mass on which improved design methods can be applied. The generation of multiple equi-probable conditioned DFN models allows the use of probabilistic methods for assessing kinematic stability, rock block size distribution as well as a range of other applications.CITATION:Rogers, S F and Booth, P W, 2014. Integrated photogrammetry and discrete fracture network modelling for improved rock mass characterisation and engineering design, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 203–208 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By G R. Hancock, D Verdon-Kidd, M J. Saynor, J B. C Lowry, T J. Coulthard

The ability to simulate the stability of post-mining landscapes over time scales ranging from decades to millennia is a critical element in the assessment of closure designs for uranium mines. Landscape Evolution Modelling (LEM) technologies provide a means to simulate and assess the long-term geomorphic stability of a conceptual rehabilitated landform for periods of thousands of years. However, a major issue with simulations derived from long-term modelling are the limitations associated with the data inputs. Specifically, simulations which utilise historic rainfall data only represent the variability of rainfall events that have occurred over a relatively short period. Consequently, these simulations run the risk of not accounting for the full range of rainfall variability that might be expected over an extended period of up to 10 000 years. Therefore, for this study a probabilistic approach was adopted to generate a stochastic synthetic rainfall data set to produce a series of unique rainfall scenarios, each representing a simulated period of 100 years. Importantly, utilising such an approach allows uncertainty in predictions to be better accounted for and provides a range or probability of likely outcomes.In this study, the effect of ten individual rainfall scenarios are assessed in terms of their impact on the predicted erosion and denudations rates produced by the CAESAR-Lisflood LEM for a conceptual rehabilitated landform of the Ranger Uranium Mine (RUM) in the Northern Territory of Australia, focusing on the Corridor Creek catchment (Figure 1). While legislation requires this site to be erosionally stable for at least 10 000 years (Commonwealth of Australia, 1987), here the focus is on the first one hundred years of landscape evolution, as this is the period in which erosion is expected to be higher, with limited vegetation cover or pedogenic development in the initial decades after rehabilitation. It is also the period where the drainage pattern is set.CITATION:Lowry, J B C, Verdon-Kidd, D, Hancock, G R, Saynor, M J and Coulthard, T J, 2016. Application of synthetic rainfall data to long-term modelling of a rehabilitated landform, in Proceedings Life-of-Mine 2016 Conference , pp 75–79 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By M Scamardella

The CSA Mine is located at Cobar, New South Wales, where it was in continuous operation from 1966 to the time it went into receivership on 29 January 1998. When it closed it was under the ownership of Golden Shamrock. Glencore International, in conjunction with Mt Lyell Mining, undertook a due diligence study to determine the feasibility to re-open the mine. This envisaged operating CSA Mine as a low-cost, copper concentrate producer under the direction of Cobar Management Pty Ltd (CMPL). The new workforce would consist of contractor trades people in operating functions under the co-ordination of CMPL staff, both on the surface and underground. This was the key to establishing the new culture in the workforce. The orebodies at CSA Mine are steeply dipping with copper-lead-zinc mineralisation in zones of strong alterations in a fine-grained siltstone host sequence. The predominant economic minerals are chalcopyrite, sphalerite and galena. The major gauge minerals are pyrrhotite, pyrite, chlorite, sericite and quartz. Ore for the project is being developed and mined from two high grade copper lenses within the QTS North system. Chalcopyrite occurs in two forms. The first consists of coarse chalcopyrite grains in association with pyrrhotite or pyrite. The second form consists of chalcopyrite grains intergrown with pyrrhotite grains. This form of chalcopyrite is quite rare. It allows electrochemical interactions between grains, resulting in rapid oxidation of the chalcopyrite surface. Physically this ore looks like, and has been mistaken for æpeacock oreÆ, ie bornite, but is infact oxidised chalcopyrite.

Jan 1, 2000