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By P B. Hills

Almost a quarter of a century since Bridges (1993) documented techniques for the assessment of ground conditions in a seminal paper in the Proceedings Second International Mining Geology Conference, the necessary role of the geologist in recording geotechnical data on exploration properties and in mines remains. Typically, the geologist is the first professional on the exploration property. Of course, most exploration properties don’t become mines. However, when a property does start to come together and form a coherent mineral deposit and professionals from across the minerals industry spectrum, including specialist geotechnical engineers, become increasingly involved, it remains the geologist who has the most intimate knowledge of the deposit. By association, that knowledge extends to the character of the rock mass.Throughout the various phases of prefeasibility, feasibility, construction and production, culminating in the mature mine, the knowledge of the rock mass held by the geologists continues to grow. In the current era of minimising cost and optimising profit, meeting the requirements and expectations of stakeholders ranging from fellow employees to investors, industry and financial regulators and the broader public, in a social environment where occupational health and safety concerns are of uppermost concern in every endeavour, the value of the geologists’ observations cannot be understated. Mines nowadays employ more geotechnical engineers than they did in the early 1990s when Bridges (1993) wrote his paper. More funds are available for specific geotechnical investigations of exploration properties and mines; none-the-less, those programs remain limited in their extent and there is a wealth of additional data available for collection with the appropriate training, at little additional effort. Fundamentally it is all about the numbers. Any hole not geotechnically logged is a hole that will need to be drilled again if the data is required. Any face, surface or underground, not geotechnically mapped is one that may need to be mapped a second time. That doesn’t mean every hole or every face. However, it is the proposition of this paper that the opportunity for additional geotechnical data to be gathered during traditional geological investigations is an opportunity that cannot be ignored. Occupational health and safety requirements demand that the geotechnical risks associated with mining are appropriately managed. Mining regulations in most Australian and overseas jurisdictions requires the consideration of geotechnical risk through formalised management plans. The Joint Ore Reserves Committee (JORC) Code requires the consideration of modifying factors more than ever before. The benefit to be realised through improved geotechnical understanding by geologists on the ground leads to improved occupational health and safety, optimised reporting compliance, and improved financial and social outcomes for the exploration property and ultimately for the mine that follows.CITATION:Hills, P B, 2017. The necessary role of the geologist in geotechnical data gathering, in Proceedings Tenth International Mining Geology Conference 2017, pp 347–354 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By A Mcquillan, N Bar

Geotechnical models developed during the open pit mine planning stage are generally three-dimensional (3D) in component to capture the spatial variation in geological, structural, hydrogeological and geomechanical conditions. Yet when geotechnical analysis is completed, often the 3D geological, hydrogeological and structural models are simplified to two-dimensions (2D). This paper demonstrates this simplification, through referenced case studies, can lead to the wrong failure mechanism being analysed and/or a conservative Factor of Safety (FOS), or Strength Reduction Factor (SRF), being calculated, leading to a false sense of stability. There exists a paradigm that the FOS calculated using 2D limit equilibrium (LE), or the Strength Reduction Factor (SRF) calculated using 2D finite element (FE), modelling methods is generally conservative, ie lower, than the true FOS. However, this assumption that 3D FOS, or 3D SRF, is always higher than 2D FOS, or 2D SRF, is not always correct (Chen and Chameau, 1983; Bromhead and Martin, 2004; Herza et al, 2017; Pyke, 2017; Dana et al, 2018).

Nov 29, 2022

Anglo Platinum recognised with its expanded operations the need to change its evaluation strategy due to increased sample volumes and the pressure it created at laboratories. The sender/receiver analytical scenarios had to change in order to curb costs and to prevent substantial investments in new sampling and analytical facilities. Given the high cost associated with correct sampling systems and sampling protocols and the shortage of technical resources a strategy of single point sampling and analysis was introduced. The analysis was then done at an ISO17025 accredited laboratory with ten per cent checks, subjected to careful statistical scrutiny. Logistical problems increased with respect to weighbridge congestion, maintaining sampling quality, throughput of samples in the sample preparation areas, manual quality control systems in place, audit trails and analytical capacity throughout all operations. This required the expedited improvement of existing sampling practices and the development of new sampling methods and equipment. Anglo Platinum is classifying and standardising sampling equipment, sample preparation and analytical procedures for all process streams with the view to minimise overall uncertainties. Major investments were made into a customised LIMS and automated equipment for data management, reduction of manual transcription errors and streamlining of sample processing. Anglo Platinum is committed in rolling out the enhancements to all sites as priority dictates.

Jan 1, 2008

By T Brown

Australia is now committed to the most significant period of infrastructure investment since the 1960s and the current climate of project finance and public private partnership (PPP) model uncertainty means it is imperative that the affordability and certainty in delivery of infrastructure projects is maximised.In light of the current and forecast levels of infrastructure investment it is worth drawing comparison with a similar period of Australian expansion when the nation’s first railways were constructed. Similarly to over a century ago, we are following a trend in rapid development and are already reaping the inefficiencies that could be avoided with broader technical planning and improved client coordination.The original rail networks were developed by the individual states before they combined to form a Federation of states in 1901. As a result of the adoption of different gauges by 1917 a passenger wanting to travel by train from Brisbane to Perth had to change trains six times.Similarly in 2011, there is little parity between Australian states on the quality requirements (performance specifications) for road tunnels. Differences between states start most significantly with the size of the specified traffic envelopes, thus the size of tunnel required. Where ambiguity and differences exist in project documentation, performance specifi cations (PS) and broad technical requirements for road tunnel projects, any associated risk in interpretation ultimately ends up being incorporated in the bidder’s (constructor’s) final sell price.Whilst not nearly as inconvenient as having to change train at each state border, and largely unnoticed by the general tax paying motorist, this paper examines examples of apparent minor differences in Australia’s recently constructed road tunnels to highlight the differences in road tunnel specifications.The paper identifies how these small differences manifest themselves in major price penalties between projects and further, highlights the need for further specification review, refinement and standardisation across road tunnel jurisdictions to increase road tunnel affordability.

Mar 8, 2011

MANPOWER RESOURCES The optimisation of human effort has been an ongoing and significant process in the coal industry since industrialisation as we know it began. The extent to which the changes sought have been achieved has, over the years, been in the main determined by the economic and political forces existing at that time and the determination and character of the individuals involved. The question of optimisation is therefore not new in our industry. Hopefully this presentation will demonstrate to the reader the effect of previous measures adopted by industry to optimise all facets of its operation and in particular that of the human Resource.

Jan 1, 1991

The need for the hydraulic transportation of coal in the New South Wales coal industry, both from the coal face to the surface and from the coal mine to the consumer or the port for export, is explained. Details of research projects currently in'progress and involving the hydraulic transportation of New South Wales coals are given together with information on the hydraulic transportation of coal in the United States of America.The potential of hydraulic transportation as a viable alternative to the proposed expansion and upgrading of the New South Wales railway system to meet the projected New South Wales coal production to the year 2000 is described.

Jan 1, 1980

By Benson R. P

Building a new tunnel to accommodate CN North America's needs or double stacked container traffic for the next 100 years represents new and unprecedented challenges. Innovative approaches to contracting, especially the Negotiated Compressed Process (NCP), TBM design, project management, and the regulatory and approval process, were all required to deliver a new tunnel to meet the needs of CN North America within the approved completion schedule of 33 months compared to a traditional approach of 45 to 48 months. The NCP resulted in trimming a full 12 months from the project schedule with an anticipated saving of direct and indirect costs.

Jan 1, 1993

By Corbett GJ, Leach TM

The Nena Cu-Au high sulphidation deposit has formed within the Frieda River Intrusive Complex in association with a major dilatant structure. Multiple intermediate intrusives of Miocene age are localised by a splay (Frieda Fault) of the Fiak-Leonard-Schultz Thrust, a several hundred kilometre long structure, formed parallel to the accretionary prism of northern Papua New Guinea.The high sulphidation systems including Nena, crop out as narrow silica-alunite ridges extending for up to 5-6km in length within a dilational structural environment. Alteration at Mena exhibits two phases of hydro-thermal activity: an initial stage, inferred to be volatile-rich, which has produced zoned alteration; and a later phase, postulated to have been a liquid-dominated fluid, which has brecciated earlier alteration zones and deposited gangue phases as well as Cu/Au-bearinq sulphides in open spaces.

Jan 1, 1994

By G Malherbe, J Gonzalez, D C. Franklin, J Bassan, C T. Farrelly

To respond to ever-increasing challenges, mining companies have been experimenting with new business models and technologies in order to speed mine development, production, processing and transport. The various experiments involve mobile access to data, intelligent sensors, advanced analytics, virtual collaboration, virtual reality, automated equipment, remote operations centres and strategic partnerships. A synthesis of all these components creates a ænetwork effectÆ that can dramatically improve the overall effectiveness the entire operation. The concept of the Network Centric Mine borrows from a variety of industries, including defence, aerospace, aviation, petroleum, utilities and manufacturing. Central to the concept are improvements to the way we connect people, process, information and technology, resulting in a more highly collaborative business model, with roles and processes designed to take advantage of new technology. The components of the mining operation act as a connected network aimed at a common goal, regardless of the boundaries of organisation and location.The design of this new organisational ecosystem needs to take into account the recent advances that enable the æplug and playÆ integrated collaborative environment, including cloud computing, mobile devices and social networking, as well as advances in augmented reality, robotics, geo-location, digital labelling, simulation and analytics. However, the most consistent lesson from other industries is the need to properly enable the behaviour and process changes necessary for success.Benefits from adopting a network centric approach include the more effective use of scarce expertise, improved data and information analysis, reduced process variance, and more informed and faster decision-making. The future of mining will see more technology savvy workers who will drive the adoption of new processes. The operations will shift from a relatively static and disparate set of functions, to a digitally aware, dynamic, automated, integrated and interactive environment, with increased agility, lower operating costs, higher productivity and improved safety.CITATION:Farrelly, C T, Malherbe, G, Gonzalez, J, Bassan, J and Franklin, D C, 2012. The network centric mine, in Proceedings International Mine Management 2012, pp 143-160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By K Hines

Anglo Platinum is the worldÆs largest producer of platinum group metals, and also produces large quantities of nickel, copper and cobalt at its Refining complex in Rustenburg, South Africa. In 1995 Anglo Platinum embarked on a smelter modernisation project, primarily to reduce site emissions to below the guideline limit of 20 tonnes per day SO2, but also to increase the converting capacity in line with future projected production profiles. To achieve these requirements the existing Pierce Smith converters were replaced with a single large Ausmelt converter and a new acid plant. This was the first time that an Ausmelt furnace had been used for converting, but it had the advantages of being a very robust furnace and was fully enclosed, giving good gas capture. It was thus considered the most appropriate technology from both a process and an environmental perspective. It also enabled the smelting and converting furnaces to be decoupled. The plant was commissioned from late 2001 and the first tap was in June 2002. Despite being a new technology, ramp-up has been similar to other large scale pyrometallurgical operations. Numerous process improvements have been made since start-up, most notably a change from two-stage batch to fully continuous, resulting in the plant now operating above design in terms of throughput. Optimisation of freeboard accretion control was also a major component of the ramp-up activity. This paper discusses the commissioning and ramp-up issues of the new Ausmelt converting furnace, concentrating on the design and process changes, and summarises current operating performance against the original design objectives.

Jan 1, 2005

To follow the development of the central crushing plant it is necessary briefly to outline the history of the Lake View and Star Limited. This Company, when first constituted, took over the properties of the Lake View Consols, Hannan's Star, and Chaffers Gold Mines.The Company then treated the ore won from these leases at two dry crushing, all-roasting plants, situated adjacent to each other on the site of the present Chaffers Treatment Plant that handles all the ore won by the Lake View and Star Ltd.SUbsequent to the initial union of the three companies mentioned, the Ivanhoe Gold Corporation and the Golden Horse Shoe Ltd. were absorbed. Still later, and after the original crushing plant was erected, the Associated Gold Mines of Australia were purchased.A very extensive development policy was adopted by the Company's management in the late 1920's, and as the underground programme progressed, it became eVident that a large treatment plant would be required. Wet milling of the ore, followed by flotation, was considered desirable, and the necessity of a central crushing plant capable of producing a feed that could be handled by the wet ball mills attached to it was obvious.At this time, each of the properties absorbed had its own crushing station, situated adjacent to the respective...

Jan 1, 1948

By Miskelly N

The Joint Committee of The Australasian Institute of Mining and Metallurgy (AusIMM) and the Australian Mining Industry Council (AMIC) have published a Code for the Reporting of Identified Mineral Resources and Ore Reserves. The Code is the result of an initiative begunin 1971 to achieve industry self regulation of Resources and Ore Reserves reporting which resulted first in guidelines for reporting standards but which have now been incorporated in ASX Listing Rules as a Code withsignificant sanctions ensuring compliance. This paper describes the background to the Code, its key provisions, and comments on practical aspects of1 working with the Code and compliance issues.

Jan 1, 1990

By Y, Li Jianxiong, Hu Hua, Gu Desheng

After having briefed the technical and economical advantages of continuous mass mining in underground metal mines, the authors discuss the four stages of research and development of continuous mass mining in China. The four stages are: vibrating ore drawing in a stope, continuous mass mining in a stope continuous mass mining without rib pillars in an area and continuous mass mining in whole mine. The authors briefly review the research achievements of the first and the second stage; Combining the key national research project of the æNinth Five Year PlanÆ ù æThe experiment and research of continuous mass mining without rib pillarÆ, the authors introduce in detail the technological condition of mining, the design ideas of continuous mass mining, the design scheme of mining, the technology of mining. the equipment of mass mining, the chief research achievements and so on. The success of research of continuous mass mining without rib pillar indicates the arrival of the third stage of research. The introduction of continuous mass mining will promote the technology revolution of mining in China remarkably. The authors also point out that the development direction of continuous mass mining of the 21 century is continuous mass mining in whole mine, which is the fourth stage of research.

Jan 1, 2000

By D S. Stewart, K W. Keskimaki

In 1999, the Henderson Mine commissioned the Henderson 2000 project - a new truck haulage level, a new underground crusher and a 24 kilometre conveyor system to replace a 23-year old rail haulage system. Henderson has been able to continuously improve in almost all aspects of its rubber-tired mining. The rail haulage system represented one of the last barriers to continuous improvement to the overall plant performance. Many of the lessons learned in other areas of the mine were utilised to design the truck level. This paper chronicles the benchmarking, equipment selection and design of the level. Areas covered will include haulage trucks, level layout, ore chute design, traffic control, road design and crusher layout.

Jan 1, 2000

This paper describes the new iron and steelmaking process recently commissioned at NZ Steel. Ironsand mined and concentrated at Waikato North head is slurry pumped 18 km to the company's Glenbrook works. Ironmaking includes the direct reduction process pioneered at Glenbrook in the 1970s and a new continuous electric melter. The molten, high carbon pig iron produced is then fed to a vanadium recovery unit and on to the KOBM oxygen steelmaking vessel. Steel is cast into billets or slabs. The new plant, which is the first stage of a fully integrated works at Glenbrook, raises New Zealand Steel's production capacity from 150 000 t/y to 750 000 t/y.

Jan 1, 1986

The latent conditions clause in various general conditions of contract have traditionally proved to be a source of significant disputes in tunnelling contracts, even when extensive geotechnical investigations have been carried out at the tunnel site and a report of these investigations provided with the tender documents, informing the contractor of the nature and extent of subsurface conditions likely to be met with during execution of the works. This paper discusses the contractual aspects of the new latent conditions clause in the recent Australian Standard AS 2124-1986, General Conditions of Contract, in relation to tunnelling contracts. A comparison of this new clause is made with other latent conditions clauses in general conditions of contract in use in Australia and other commonwealth countries. It is seen that the new latent conditions clause in the recent Australian Standard 2124-1986 has, by providing for a reasonable apportionment of risks, attempted to minimize contractual disputes relating to latent conditions in tunnelling contracts and to provide a satisfactory basis for quick and efficient settlement of such disputes should they arise during execution of these contracts.

Jan 1, 1987

In this paper is given a description of the flotation plant recently erected by Broken Hill South Limited at the South Mine, Broken Hill, N.S.W. It has been built on the site of the old flotation plant, which was described in a previous paper published by the author. The present paper is supplementary to the former paper in that it replaced the following sections thereof, namely, those from end of the second paragraph, page 269, to the end of the first paragraph page 282, and from the end of the second paragraph, page 284, to the end of the third paragraph, page 302.The roll crushing, fine grinding, gravity concentration, filtration, disposal of products and sampling in the new plant are the same as described in the above mentioned paper.The reconstruction of the flotation section, described herein, completes the reconstruction and modernisation of the treatment plant which was begun in 1928. A description of these earlier alterations has already been published in the Proceedings of this Institute.

Jan 1, 1935

The management of safety has undergone a number of radical changes in the past 100 years. The most important paradigm shifts occurred through the work of Heinrich, followed by the advent of the safety systems era and, more recently, the behavioural safety approaches that have become increasingly popular around the world. Each of these æapproachesÆ to safety has left an indelible mark on the way we target safety improvements, helping decide which interventions are deployed and how they will be measured. They have also resulted in a number of æmythsÆ about safety management, each of which will be discussed, analysed and challenged in this paper. This paper highlights the complex problem of æcomplacencyÆ, that has arisen out of the increased levels of regulation and consequent perceived protection that workers enjoy in the work place. It also looks at a phenomenon called æaccident migrationÆ which results from a superficial treatment of accidents with changes to rules and procedures. The most recent approach to safety is generally known as behaviour-based safety, which flowed from the human sciences and quality management era. This approach has had a dramatic impact on the way safety is managed around the world, but still falls short in a number of key aspects, most notably the area of risk awareness and risk understanding. Many workplace accidents occur simply because the risk is unidentified, underestimated, not understood or ignored. This paper proposes a new direction for safety, called competency-based safety. It is based on cognitive psychology aimed at combating the consequence of modern protection. A case study is presented detailing the deployment of this approach throughout Placer Dome.

Jan 1, 2005

This paper describes the new legislative regime that will apply to the regulation of the minerals industry in New Zealand. The reform of New ZealandÆs minerals legislation was initiated in January 1988 when the Minister for the Environment, Rt Hon Geoffrey Palmer, announced the Governments intention to review all the major laws governing New ZealandÆs resources. The Resource Management Bill is scheduled for introduction to the House in December 1989 and its date of enactment is scheduled for June 1990. With some matters still to be determined (at the time of writing), this paper cannot be a definitive review and description of the new legislation, it is instead an attempt to outline the major features of the Bill, to date, that are seen as important to the mining industry.

Jan 1, 1990

By Dip L. B

This paper describes the new legislative regime that will apply to the regulation of the minerals industry in New Zealand.The reform of New Zealand's minerals legislation was initiated in January 1988 when the Minister for the Environment, Rt Hon Geoffrey Palmer, announced the Government's intention to review all the major laws governing New Zealand's resources. The Resource Management Bill is scheduled for introduction to the House in December 1989 and its date of enactment is scheduled for June 1990.

Jan 1, 1990