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Pike River Coal Limited is in the process of developing the Pike River Coal Mine in the Paparoa Ranges of New ZealandÆs South Island. The mine will be developed to extract a coking coal deposit of the Brunner Seam, some 46 km north-east of Greymouth, using a combination of continuous miners and hydraulic extraction. The mining area is located within Department of Conservation (DOC) land and is adjacent to the escarpment of the Paparoa Range and the Paparoa National Park.   As such, the major restriction to planned extraction is protection of: +        the western escarpment, +        vertical and sub-vertical rock faces, +        permanent water courses, +        significant vegetation, and +        steep slopes.   The mine will use its elevation advantage to hydraulically flume coal from the working faces to the pit bottom area where it will be slurried to approximately 35 per cent density of solids and pumps down a slurry line to the coal prep plant some 10.5 km down the Pike River Valley. The coal will be sold on the export market as a high quality coking coal for international steel making.

Jan 1, 2006

And it takes more than good organisation. You may read or heard this poignant reflection: We tried hard, but it seemed that every time we were beginning to form up in teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by re-organising, and a wonderful method this is for creating the illusion of progress while producing confusion, inefficiency, and demoralisation This was written by the Roman Gaius Petronius in AD65. How much have things changed in nearly 2,000 years? What then does it take besides the fundamentals and good organisation to build a successful career in a successful organisation? I'm prepared to venture a list of what I'll'call Tips for Young Professionals. If you've got what it takes, and apply these, I think that you'll gain a great deal of satisfaction from your career, even if you don't reach the distant target each of you should have in mind now. So settle back in an advice-receiving mode, and please forgive me if I come across as a master of the bleedin' obvious, as Basil once accused his wife Sybil of being in the unforgettable Fawlty Towers.

Jan 1, 1990

By J St George

Much of AucklandÆs transport infrastructure has been developed on surface with little or no consideration of underground options. Current and planned transportation routes are now facing high costs due to land values and increasing environmental resistance to surface development. The option of utilising underground space becomes a feasible investment decision for these links as well as being the only option to develop the rail network within the inner city area. Transportation tunnels offer a quieter, more energy efficient means of getting around with minimal impacts on the surface environment. One of the major impediments to tunnelling is the high construction cost, which is partly related to the risks of encountering unexpected ground conditions and/or the possibility of causing surface ground deformations which could damage structures. The geology of Auckland has had substantial investigation through various studies and projects. The sediments of the East Coast Bays Formation (ECBF) underlie most of the Auckland urban area. It is classified as a soft rock and is a suitable material to tunnel through using either a tunnel boring machine or a roadheader. This paper reviews the limited amount of tunnelling completed in the urban Auckland area, together with the international advancements that have been made in the tunnelling industry. From the known features of the local geology and the problems encountered historically, the likely risks of tunnelling in Auckland are presented and ways in which those risks could be reduced and managed, are discussed. In addition, contractual arrangements between client and contractor are assessed with respect to complicated projects (such as tunnelling), so that the risks can be managed to create efficient infrastructure routes with reduced costs.

Jan 1, 2008

By S R. Grano, J Duan, T A, D Fornasiero

We have determined the experimental rate constants for chalcopyrite particles floated from a complex sulfide ore and compared them with those calculated using a recently developed flotation model. The model incorporates contributions from the efficiencies of collision, attachment and stability between particles and bubbles, as well as their frequency of collision. For these calculations, the contact angle of the chalcopyrite particles in the ore was obtained independently using a surface spectroscopic approach. The calculated flotation rate constants were in good agreement with the experimental data and able to reproduce the characteristic maximum in flotation rate constant for particles of intermediate size. The values of bubble velocity and turbulent dissipation energy derived from these calculations are relatively low and may well correspond to mean values of these parameters inside the flotation cell. We have extended this approach through the application of a property based model to an operating plant, with a satisfactory outcome.

Jan 1, 2005

South Africa is a semi arid, water scarce country that has undergone recent major political and social transformation. This transformation has ensured that water management has become a primary environmental concern in the South African mining industry, raising the status of water from an ancillary service to a fundamental factor in mine planning. The coal mining industry has been involved in the development of integrated catchment management plans since the late-1980s when a series of initiatives commenced in catchments where collieries operated. The plans focused attention on water supply and water demand management, the equitable access to water supplies, and intersectoral approaches to decision making, before the promulgation of new legislative and policy frameworks. Development of an integrated watershed management plan for the Olifants River basin, located in the Mpumalanga province, commenced in 1990. The Olifants River is an international river basin of 54 570 square kilometres and shared by South Africa and Mozambique. The upper watershed, locally called the Witbank Dam catchment, will be the focus of this paper. It has an area of 3400 square kilometres and is the major coal mining, power generating, and maize-growing region of the country. The processes embodied in the integrated watershed management plan had no formal guidelines but rather developed in an ongoing fashion over time. The plan commenced with a situation analysis involving the major stakeholders that identified principal technical shortfalls. These shortfalls were investigated under the guidance of multisectoral committees. The Olifants River Forum was started to extend awareness of the initiatives on an informal level throughout the whole watershed. The results of the investigations enabled water quality guidelines to be established for the upper catchment. To achieve the guideline levels additional initiatives were developed including a scheme to manage mine water discharges into the river system, the development of a standard four-step water management process, investigation and development of innovative mine water treatment processes, specifically sulfate reduction technologies, the use of gypsiferous mine water for irrigation, river and dam hydrological models, groundwater models and biomonitoring. Significant outcomes from the process have been achieved including the improvement in water quality in the Witbank Dam catchment. Equally significant have been the development of partnerships between businesses and between businesses and the community specifically in the use of mine water for irrigation. The plan realised a number of requirements for success including, the development of trust, openness and transparency with information, the essential need for consultation and negotiation and the involvement of third parties to validate information. The future still holds the potential for disputes between upstream and downstream water users but understanding, transparency and accountability between all players have, and will in future, enable the matching of the increasing demands on a scarce water resource to the needs of all.

Jan 1, 2003

By T Isaksson, J Anderson

The procurement process for underground construction contracts, in particular those contacts involving tunnel boring machines (TBMs), is subject to many complex and inter-related variables, including national and local politics, public policy, community involvement and media attention û as well as strict environmental and legal requirements. Other restrictions include the time available to adequately investigate geotechnical conditions and viable technical options to determine the best construction methodologies û including selection of tunnel boring machine characteristics and, those construction means and methods suitable for the specific geotechnical and environmental conditions. The latter are, most often, quite imperfectly understood. æGetting it rightÆ implies that an optimal configuration û of machine type, characteristics and associated methodologies û can be found and successfully implemented for a particular project. æFrom the beginningÆ implies that the lack of time issue can be successfully resolved. Within an international context this paper highlights a number of issues of concern which relate to tunnel procurement systems and the ways in which certain key processes are managed during planning, design and construction. The authors argue that there is considerable room for improvement in the way tunnelling projects are undertaken and an approach is discussed which has the potential for substantial gains in cost and schedule and reduction of risk. Savings, however, may only be fully realised if the new methods can be fully implemented by all parties involved. This, we believe, will require the rejection of ætraditionalÆ forms of management and procurement with associated changes in the roles and responsibilities of owner, engineer and contractor. Additionally, risk identification, assessment and mitigation are essential cost and schedule control process which have, to this point, been underutilised by the underground construction industry.

Jan 1, 1999

In late 1984, Council of the Australasian Institute of Mining and Metallurgy accepted a proposal to establish a Mineral Heritage Committee. This was to be involved in matters relating to mineral heritage-its recording, its preservation, and the acknowledgement that it can be of use to the mineral industry in the future. The Committee was established to ensure that all of the disciplines of our profession were included and that, so far as possible, all of our country as well as those countries of the Southwest Pacific Basin were represented. Some work has been commenced to bring real- isation of the importance of the heritage of our mineral industry to the forefront of the commu- nity's interest. There is not a state in this country and the Southwest Pacific where the mineral industry has not at various times proved to be the basis of community development.

Jan 1, 1987

Analysis of the topography associated with large vertical strains measured in the upper crust in the Basin and Range and elsewhere in the US Cordillera shows that it varies systematically with upper crustal strain such that it decreases where tectonism has resulted in relative thinning. The magnitude of topographic deflection suggests that the amount of thickening or thinning of the upper crust cannot also be reflected in vertical motions of the Moho discontinuity, nor can the vertical strain be isostatically accommodated by inflow or outflow of asthenosphere, mantle lithosphere or mafic lower crust. Simple isostatic calculations show that the compensating medium had a density probably within 100-200 kg/m of average upper continental crust, thus indicating that the compensating medium lies within the crust and is probably in large part quartzose. This conclusion is in accord with laboratory experiments on the strengths of rocks, and with reflection seismograms in deformed regions which suggest that the Moho is generally flat beneath regions of extreme gradients in upper crustal vertical strain. The upper crust floats on a quartzose layer in the mid-crust which, under orogenic conditions, is apparently so weak that it behaves as a relatively inviscid fluid at geologic timescales (> 10,000 a) and subcontinental lengthscales (100-1000 km).

Jan 1, 1990

By A E. McElnea, M A. Martens

An 18-month project was undertaken to test the effectiveness of controlled daily tidal exchange augmented with hydrated lime treatment of surface waters as an approach for remediating a severe acid sulfate soil disturbance at East Trinity, Cairns, north Queensland. Actual acid sulfate soils were producing hazardous levels of acid and heavy metal contaminants and degrading approximately 720 of the 940 ha East Trinity property and the adjacent foreshores. A government-led research team established a series of research projects with the aim of characterising the site (soils, water, terrain) and testing the effect of the lime-assisted tidal exchange management strategy on soils, water, sediments and biota.

Jan 1, 2003

By T Craske, J Sykes, T C. McCuaig, M Jessell, A Trench

The prevalent strategic approach in the mining industry is one of planning. However, it is widely recognised that planning does not work in complex and uncertain situations (Mintzberg, 1994), such as those associated with ‘above ground’ non-technical orebody complexity (Trench, Packey and Sykes, 2014). Mintzberg, Ahlstrand and Lampel (2009) suggest the focus instead should be on strategic ‘thinking and doing’ and using the many ways to think about strategy to make sense of complex, uncertain, and unique situations. They therefore place great value in cognitive flexibility. Scenarios development utilizes several different thinking styles and thus assists with this type of flexible strategic thinking (Figure 1). The ‘Centre for Exploration Targeting (CET) Scenarios’ were developed with the ‘Oxford Scenario Planning Approach’ (OSPA) (Ramírez and Wilkinson, 2016). The OSPA aims more to improve the thinking skills of decision makers, rather than forecasting per se (Wack, 1985a, 1985b). As such, this paper focuses less on the content of the scenarios and instead on the practical value of scenarios in strategizing. CITATION: Sykes, J, Trench, A, McCuaig, T C, Jessell, M and Craske, T, 2018. Strategic thinking about long-term ‘above ground’ orebody complexity using scenarios, in Proceedings Complex Orebodies Conference 2018, pp 60–64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By P Lamberg, M Lyyr, S Heimala, J Liipo

Since the introduction of froth flotation for industrial practice, the process has long been developed and improved by making cultivated guesses or by using trial and error methods to a varying degree. Fresh possibilities have emerged after development of new surface sensitive analysing methods and in situ electrochemical methods. Having had the possibility to combine different findings between science and everyday plant practice, Outokumpu has been able to develop a catch-all procedure to manage a flotation process taking into account the specific requirements set by different minerals in a slurry. A number of these procedures are available and offered globally to clients as part of a Plant Audit service. The Outokumpu Plant Process Audit (Process ef-X) concept comprises of mineralogical determinations from process samples and plant data analysis together with electrochemical process measurements using mineral electrodes. Automatic control loop analysis can also be included. The objective is to combine the results for a basis of flotation process improvement. Since this methodology has earlier been an in-house practice, it follows that the results are also reflected in the development and design of the OutokumpuÆs processing equipment. An increasing number of ores have a very intimate fine-grained texture and it may be physically impossible to combine high grade with acceptable recovery by a flotation process alone. For such cases, combinations of different hydrometallurgical û mineral separation û pyrometallurgical processes are available. Mineral specific information and chemical expertise of flotation technology can be utilised in development of other processes, as well.

Jan 1, 2005

By G L. Simmons, K M. LeVier, R Kappes

The low potential hydrophobic state of pyrite in amyl xanthate (PAX) flotation with nitrogen is of particular interest with regard to the N2TEC flotation technology currently being used for the recovery of auriferous pyrite at NewmontÆs Lone Tree Plant in Nevada. Initially, the N2TEC system had been found to operate satisfactorily, but cyanide in the flotation mill water appeared to be responsible for a loss in pyrite recovery. This supposition was confirmed with laboratory experiments, and a program was initiated to study flotation chemistry variables by electrochemically controlled contact angle measurements. Experimental results show that activation of pyrite in such cyanide solutions can be achieved more effectively with lead than with copper. Subsequently, based on these fundamental studies, significant improvement at the Lone Tree Plant was achieved by lead activation, in which case the recovery increased to expected levels. The effect of activator is particularly significant not only with respect to pyrite depression by residual cyanide, but also with respect to collector (PAX) consumption and the initial state of the pyrite surface. Experimental results show the importance of the pyrite surface state and the rather interesting features of the activation process.

Jan 1, 2005

By E du Plessis, J Kapusta, J L. Mauk

The world-class Bulyanhulu gold deposit (375 t Au) is in the Sukumaland greenstone belt, Northwestern Tanzania. The main mineralised quartz vein structure, termed Reef one, occurs at the contact of felsic metavolcanic rocks on the hanging wall and mafic metavolcanic rocks on the footwall. Reef one is dominated by massive quartz together with pyrite, pyrrhotite and minor chalcopyrite. Alteration in the footwall basalt is characterised by extensive chloritisation, calcification and silicification, which is strongest near the vein. Sericitisation also locally occurs adjacent to the vein. Metamorphic hornblende and plagioclase (albite) increase in abundance at a distance of 120 m from the vein and reflect the gradation into less altered rocks. The increasing abundance of chlorite, calcite, quartz and local sericite near Reef one, coupled by replacement textures suggests that most of these footwall minerals are the product of hydrothermal alteration, rather than regional metamorphism. Geochemical data shows slight enrichment in Ca, Fe and As towards the vein, whereas Zn in several drill holes becomes enriched away from Reef one. The Bulyanhulu gold deposit is a quartz-pyrite-chalcopyrite shear controlled vein with an adjacent extensive chlorite-quartz-calcite hydrothermal alteration zone (and a limited local sericite alteration zone) that passes to a hornblende-albite metamorphic assemblage further into the footwall.

Jan 1, 2002

By R H. Knight

Production mine geology must be accurate and efficient in order to reduce risk and ensure that ore value and mining operation revenue are maximised. Present grade control practices are commonly based on outmoded and inaccurate 2D geological mapping techniques where spatial relationships are estimated by eye, sketched by hand and projected to arbitrary reference planes. The 3D mapping approach outlined in this paper integrates 3D photogrammetric imagery with implicit modelling techniques to enable more accurate grade control and reconciliation in underground mines. High-resolution stereo photographs are taken of daily ore development headings. Ore contacts are traced directly on a 2D face photo using a stylus and rugged tablet. Area-weighted face grades are estimated and calculated on mapped 2D face planes. In the office, a 3D photorealistic mesh is processed and georeferenced. 2D face mapping data is transformed into its actual 3D location and true 3D mine mapping is performed by digitising oriented 3D polylines representing ore contacts and other geological features directly onto the image surface. Three-dimensional spatial relationships are fixed, eliminating the projection error of traditional 2D methods. Ore envelope and waste solids are modelled within the closed, drift-round mesh. Volume-weighted ore envelope and round grades, as well as round volume and tonnage, are calculated. Ore/waste classifications, grade, tonnage and per cent dilution are quantified per round, visually assessed in 3D and reconciled with short- and long-term models on a daily basis. Updated geological continuity models provide geological guidance in development headings under geological control and accurate 3D structural and form-line mapping improves definition drilling and stope planning. Three-dimensional imagery provides a permanent detailed survey and geological record of mine workings that can be revisited virtually to reinterpret geological ore controls in light of new observations and insights. In addition images can be used to monitor daily production performance, create training scenarios for miners, engineers and geologists and prepare management presentations. This approach adds value to underground mines by improving the accuracy and efficiency of mine geology practices. The method is particularly effective in mines with visually distinct and geometrically complex orebodies, such as those in the Balmat zinc mine located in New York State, USA, which are used to illustrate the method.CITATION:Knight, R H, 2017. 3D mine mapping – improving grade control and reconciliation in underground mines using photogrammetric imagery and implicit modelling techniques, in Proceedings Tenth International Mining Geology Conference 2017, pp 203–212 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By D Yan, D Connelly

Beneficiation of magnetite is an integral part of the future of iron ore processing. Historically, the focus of Western Australian producers has been on exporting direct shipping ore (DSO) namely haematite. The future for new DSO resources is limited so companies are changing their emphasis into processing the very large, undeveloped magnetite ores in Western Australia (WA), using beneficiation to produce shippable magnetite concentrates. These magnetite resources require higher cost processing techniques such as fine grinding and beneficiation to produce saleable concentrates. This distinct difference, from the DSO ores, has led to the development of a number of new technologies. This paper reviews: the different techniques used for magnetite beneficiation and provides some case studies in the WA industry; the use of mineral liberation analysis (MLA) to describe the nature, grain size, occurrence and associations of the mineralisation;the consideration of coarse cobbing as a critical upgrading; the application of high pressure grinding rolls (HPGR) to save energy; how the field of magnetic separation has resulted in new machines with higher field strength (SLon Separators); ultra fine grinding requirements of magnetite concentrates; andthe application of reverse flotation to reduce silica in the concentrates.

Jan 1, 2009

By C J. Moran

All mines face water management challenges. Adopting leading practice water management strategies can help reduce both operational and strategic risks. While many of the water issues faced by underground mines are the same as other operations, underground mining presents some unique water management challenges. In this paper we review trends in underground mining, water use and associated water issues. We then compile a structured set of strategic and operational risks that are pertinent to underground operations. The causes, threats, opportunities and measures for controlling or mitigating the risks are summarised. The risk compilation could provide an addendum for underground operations to the Australian governments leading practice water management handbook.

Mar 21, 2011

By E Philippa, B Miller

Material characterisation, ore sequencing and process capability are commonly regarded as the key parameters to consider in designing and operating an effective pit to plant supply chain. Therefore, an understanding of rock mass properties is the starting point for controlling the presentation of problematic material to the ore handling plant and optimising process utilisation. There are different methodologies for characterising problematic material and ore handleability which exist across a spectrum of sophistication. At one end of this spectrum are simple indices built using first principles geology and at the other are complex algorithms developed using advanced analytical methods, machine learning and ore traceability. Regardless of the method, without an integrated process for careful management of problematic ore, material handling delays (ie blocked, bridged, blinded and buried events) will interrupt the stable flow of production. The ability of the ore control geologist to mitigate these delays is central to the ore handleability challenge. This paper describes a quick and easy solution that links the presentation of ore to the operating window at the crusher. This operating window is based on material characterisation, using the physical, textural and mechanical properties of the rock mass, and crusher performance. It also describes how a basic problematic ore index (POI) can be developed using ore tracking to the production face, petrographic studies of ore texture and mineralogy, and existing variables in the geological model. Finally, this paper will demonstrate that by coding the POI into the geological model for mine planning, together with performance monitoring through compliance to plan routines, material handling delays at the crusher can be reduced, unlocking significant resource value.

Mar 22, 2022

The Paracale gold region had been known for hundreds of years, but the first professional attempts to work the lode and alluvial deposits were made only in the 1890s by the London-based Philippines Mineral Syndicate. Complex ores, transportation problems, and the Philippine Insurrection halted operations. Ultimate success went to American firms, though Frank Karuth's Philippines Mineral Syndicate had pioneered the field.

Jan 1, 1987

By Williams DJ, Battino S

The rapid crushing technique for the measurement of gas content of coal consists of accelerating the rate of gas desorption from coal by crushing. This technique allows the determination of gas content in the space of hours rather than days or weeks as required for the traditional slow desorption technique. The crushing technique is used particularly when gas content determinations are urgently required for mine safety purposes. The method is now routinely used in underground coal mines of NSW and to a lesser extent in QLD. Despite the rapidity and efficiency of this method, concerns have been raised upon the reliability of the method to deliver accurate results. Experience in Australia has shown that there is in fact some discrepancy in results between gas laboratories using the rapid crush technique. The development of rapid crushing techniques for seam gas content measurements in Australia and the main causes of variability in the gas content test results were investigated. The gas laboratories participating in the gas content testing were CSIRO Division of Coal and Energy, BHP Technical Services and GeoGas Pty. Ltd.

Jan 1, 1998

Newmont Waihi Gold operates the Martha Mine open pit at Waihi, New Zealand and is developing the Favona Underground Project two kilometres to the east. The Company is exploring the Waihi district under eight exploration permits totalling 6300 hectares.   Martha Mine is scheduled to close in late-2006. The Company has instigated and funded a significant programme of community consultation to mitigate the effects of mine closure on the community and enhance effective participation in the selection and provision of appropriate community facilities post mining.   This paper provides an overview of current issues and future developments.

Jan 1, 2004