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By C J. Unger, T Baumgartl, C J. Bond, P Sabourenkov, V C. Glenn

Social licence to mine is influenced by society’s perception of the mining sector’s ability to effectively rehabilitate mined land and for governments to appropriately regulate that process for the broader community benefit. In Queensland, Australia, many mine rehabilitation personnel working for active coalmines, as either staff, consultants or contractors, belong to the Central Queensland Mine Rehabilitation Group (CQMRG). The CQMRG was established 23 years ago with the aim of sharing informal knowledge related to practical aspects of rehabilitation in order to leave as positive a legacy as possible from mined land. This voluntary group of professionals also includes members from regulatory agencies and civil society. Within the dynamic regional mining environment, mine rehabilitation professionals benefit from sharing their informal knowledge.CQMRG is currently a group in transition. Mining boom and downturn cycles have exacerbated the loss of accumulated knowledge in the core CQMRG membership due to rapid changes in personnel at mines in the region. Additionally, some of the most experienced CQMRG-affiliated rehabilitation practitioners are approaching the end of their careers and want their valuable and less formal knowledge retained. This paper discusses the development of a research project that emerged in response to the anticipated loss of several decades’ worth of valuable knowledge as rehabilitation practitioners in CQMRG left the region or the workforce.CITATION:Unger, C J, Bond, C J, Baumgartl, T, Glenn, V C and Sabourenkov, P, 2016. ‘MRC-wiki’ – a mine rehabilitation and closure knowledge management tool for Central Queensland coalmine practitioners, in Proceedings Life-of-Mine 2016 Conference , pp 39–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By C A. Foss, K Blay, K Leslie, D Hillan

Magnetic field studies provide remote sensing of magnetisation distributions and a means to investigate moderately- to strongly-magnetised ore deposits that may be partially or totally buried. However, above-surface magnetic field surveys have limited capability to resolve the detail of magnetisation distributions because of the large separation between the magnetisation and the magnetic sensor. While some of this detail is available from magnetic susceptibility logging within boreholes or from magnetisation studies on recovered core, these measurements are limited to the exact trace of the boreholes. The large disconnect between ground or aeromagnetic surveys and highly-localised borehole sampling can cause problems in developing robust source models from magnetic survey data. The measurement of magnetic field in boreholes has the capacity to at least partially bridge that gap by measuring the magnetic field due to magnetisations proximal to, but not intersected by, the boreholes.CSIRO has developed the world’s first downhole magnetic tensor gradiometer. This instrument measures magnetic field gradients in all directions within a borehole. A prototype instrument has been built and tested as part of phase 1 of the Deep Exploration Technologies Cooperative Research Centre (DET CRC). The prototype performed well with magnetic pyrrhotite at the DET CRC test site in the Adelaide Hills and at Carpentaria’s Hawsons magnetite deposit south of Broken Hill. Further work is required to reduce the diameter of the probe so that it can operate in NQ holes (it is currently limited to HQ or wider) and to transform it to a continuous logging tool. The borehole tensor gradiometer can be used to investigate the continuity of magnetisation over a distance of several metres to tens of metres away from a borehole intersection and the structural dip of the magnetic body. It can be used to either replace or augment downhole magnetic susceptibility logging. This instrument is one component of an integrated CSIRO suite of new magnetic field utilities and methodologies for iron ore exploration and development.CITATION:Leslie, K, Foss, C A, Hillan, D and Blay, K, 2015. A downhole magnetic tensor gradiometer for developing robust magnetisation models from magnetic anomalies, in Proceedings Iron Ore 2015, pp 299–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

This paper will address this question from the point of view of a drill and blast engineer or researcher working in open cut and underground mining operations. The paper will establish a common set of reference standards for high-speed imaging and data capture, which engineers and researchers can apply when deciding which type of imaging technology is appropriate. It will present an overview of current image analysis technologies and practices in use across a range of appropriate scientific fields and draw lines of commonality of approach between these fields and the field of mining and blasting applications analysis and research. In addition, the paper will examine the different technologies from an image quality and data stream reference point, ease of operation, cost, and reliability parameters. Finally, this paper will present an argument for the hybridisation of established and new technologies which could provide a more beneficial approach to the use of imaging as a tool of quality control, research and analysis in the mining based industries. This will include a novel approach to digital high-speed imaging and data analysis in the field, which should deliver high-quality images and data analysis in a time frame that is more appropriate to the need for immediate action, analysis and problem solving.

Jan 1, 2007

By M Boyd

The University of Wollongong was named University of the Year 2000, for its work in preparing students for the e-world. Computer facilitated learning is being introduced into subjects throughout the engineering course. First year mining engineering students are introduced to computers, e-communication, using the UniversityÆs web based information system, and web based subject delivery. Mining engineering students in the mid-years of the course use programming languages and numerical computation software such as MATLAB, while students in the final years use a range of commercially available professional engineering software such as TALPAC. Most of these subjects are offered as part of the UniversityÆs Learning Online program, co-ordinated by its Centre for Educational Development and Interactive Resources (CEDIR). Learning Online subjects are delivered using the Web Course Tools (WebCT) environment. WebCT allows all resources to be accessed through the web, allows email communication between lecturer and student, and allows discussion groups for the exchange of ideas. Students can submit their assignments through WebCT and receive immediate feedback. This paper describes how WebCT has been used to deliver a first year engineering computing subject, mid-year numerical computation subjects, a mining economics subject and mine planning subjects.

Jan 1, 2002

By C Vejrazka1

The occurrence of airblasts is one of the principal mining hazards in caving operations between the time of cave establishment and breakthrough of the cave to surface. As such, it needs to be managed continuously and risk assessments need to be reviewed on a regular basis for applicability to changing conditions. The likelihood of an airblast occurring is based on a range of geotechnical factors over some of which engineers on-site only have limited control. However, the impact of an airblast to the underground mine, if it does occur, can be managed by following established safety guidelines for the production from the cave.This paper outlines how the Caving Airblast Simulation Tool in Ventsim was used to determine a risk management strategy for a sublevel and a block cave at a mining operation in Australia. The block cave has a footprint of 14 500 m2 with the extraction level located 1250 m below surface while the sublevel cave currently has a footprint of around 18 000 m2 operating between 660 m and 800 m below surface. Both caves are currently in their early operational periods. The risk analysis provided valuable information for the production planning of the caves including confirmation of extraction ratios for the block cave undercut, locations of airblast walls and maximum allowable air gaps for different muck pile heights to ensure safe operation is achieved.

Oct 12, 2022

By O Joneydi, J Viljoen, R Funnell

Computational Fluid Dynamics (CFD) modelling is a useful tool that can assist engineers in designing effective ventilation systems for the control of airborne dust generated during mining operations. Thistechnology can save time, effort and the costs associated with re-work or the traditional on-site experimental field trials by running desktop 3D simulations of the various proposed scenarios using state-of-the-art CFD analysis tools. Before implementing a dust management system, an understanding of the behaviour of airborne dust particles in the face zone can be achieved, which can improve the confidence in the secondary ventilation and dust management design. Usingadvanced numerical models, suitable dust extraction strategies can be foreseen, and multiple scenarios can be simulated and investigated quickly. As a case study, dry drilling operations in Kimberlite orebodies produce large quantities of fine dust which poses health and safety risks. An effective dust management system is required to achieve acceptable face conditions. A possible practical solution is a ducted exhaust ventilation system with a force fan in the face zone. This paper demonstrates how CFD analysis can be used as a tool to assist the design engineer with validating and optimising the proposed ventilation design by tracking the trajectories of different size dust particles, to determine the best equipment layout and appropriate flow rates which minimises airborne dust.

Oct 12, 2022

The Rum Jungle mine was operated by Territory Enterprises Pty Ltd who mined uranium on behalf of the Australian Government with operations spanning the period from 1953 to the final closure of the mine in 1971. In addition to the extraction of uranium from the open cut pits, copper, manganese and lead were mined and processed at Rum Jungle. During the latter part of the operation, and after the closure of the mine, environmental studies were carried out which were aimed at determining the causes of the pollution at Rum Jungle and identifying a rehabilitation strategy for the mine site. These studies identified sources of heavy metal and acid pollution and proposed a rehabilitation strategy which consisted of 1. recontour, construct impervious covers and controlled surface drainage on, and revegetate three overburden heaps,

Jan 1, 1984

It is no longer possible to establish a quarry on the most convenient hill then abandon the site, leaving a scar if the stone or sand in the deposit is found to be unsatisfactory. Before approval is given to operate a new quarry, the relevant authorities require a detailed plan of operations from commencement to final rehabilitation. To prepare this plan, a thorough know- ledge of the quality and size of the deposit is required. To obtain this information, the industry must use the most modern techniques available. Many examples can be given showing problems which have affected the smooth operation of a quarry for many years because the initial exploration was poorly carried out. The factors which must-be considered when exploring a deposit are detailed in this Paper.

Jan 1, 1979

Stress Mapping Technology is aproprietary technique developed to target epigenetic mineralisation located in dilatant (low stress) sites. It is a computer based technique, based on rock mechanics principles and stress-strain relationships, which seeks to transform strain data, in the form of a solid geology map, to stress data.The main assumptions in the conceptual model are that:The strain pattern of faults and lithological contacts have not been changed since mineralisation i.e. that ore formation is late in the structural history.Stress orientations and magnitudes are known.Rheological properties of faults and rock units can be deduced.The 2D geometric and rheological data is then treated by a mathematical technique which permits the geometry of the elements to be defined by the spacing and orientation of the discontinuities in the rock mass.

Jan 1, 1990

Asarco's newest concentrator near Troy, Montana, began operation in October 1981, and is presently milling ore at its design capacity of 7,710 metric tonnes per day. The underground room-and-pillar mine produces a readily floatable copper sulfide- native silver ore in a quartzite gangue. Major sulfide minerals are bornite and chalcocite with minor chalcopyrite; fine grained native silver occurs with the copper sulfides. There are also minor amounts of native copper and copper oxides in the ore. A rougher copper-silver concentrate is floated, reground and cleaned twice. Cleaner tail is scavenged, and the scavenger concen- trate is combined with rougher concentrate for regrinding. Rougher flotation tailing and scavenger tailing make up final mill tailing which is disposed of by spigotting into a tailing dam located 10.5 km from the mill site.

Jan 1, 1978

By Brown P. L

A study has been made of the geochemistry of the Ronneburg mine district as input to the overall management strategy for the rehabilitation of the mine site. The study drew on the geological data and information store developed over the 40 years of mineral exploration and mining at Ronneburg, and on chemical data from the literature which described the chemical processes of weathering, oxidation, dissolution and precipitation of minerals. The geochemical processes were divided into three groups based on their rate of reaction. Fast processes were assumed to proceed to equilibrium and were modelled using equilibrium chemistry equations; slow processes were assumed to be proceeding at a quasi-steady state rate and were modelled using chemical rate equations; very slow processes were assumed to have no role in describing the geochemistry for rehabilitation purposes.

Jan 1, 1995

Kensington is a joint venture between Echo Bay Mines and Coeur Alaska, a subsidiary of Coeur d'Alene Mines Corp. The venture is of equalparticipa- tion and is governed by a management committee with Echo Bay as the operator. The project site is 50 miles north of Juneau, Alaska on the eastern shore of the Lynn Canal. The mine and mill are being planned for a production rate of 4,000 stpd. Currently, probable reserves stand at just over 11.3 million tons grading 0.149 oz Au/ton. The project is now in final feasibility study with a production decision anticipated by the end of 1990. Commercial production would begin early in 1993. This presentation dis- cusses the anticipated mine, mill and support aspects of the project.

Jan 1, 1991

By Ross C

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

Although technology and circumstances are in a constant state of change, the principles of managing the human element remain constant. The isolated mining community continues to form the backbone of the minerals industry but the nature of the isolation, along with the economic and political environment of the industry, is changing. These changes require new inputs by management to the workforce. Management must determine an effective working relationship with unions on its mine site and concurrently contribute to the build- up of the expertise of the individual worker through training and communication. It must also retain a proper balance, by way of human contribution, in cost and information reporting and in other areas amenable to computerisation. These comprise the aids to management necessary to achieve the desired operating efficiency and profitability.

Jan 1, 1980

By Buttrose RB

The Pine Creek gold mining development consists of a 1000000 tonne/yr open cut mine, a carbon-in-pulp processing plant and support facilities. The operation is located at Pine Creek, 230 km south of Darwin in the Northern Territory. The mine was officially opened in late October 1985, having been designed and constructed in less than twelve months, despite front end expenditure constraints and unseasonal cyclonic rains shortly after commencement of site activity. Non-traditional methods and attitudes were required to be adopted by both Engineer and Owner to successfully bring the project from preliminary design through construction and commissioning in a minimum time. Those areas which differ from the more traditional approaches to Project Management are examined together with a review of the advantages and penalties of these methods.

Jan 1, 1986

By C Deacon

It is common practice to include microspheres or similar density reducing agents in inherently insensitive water-based commercial explosives to achieve detonative sensitivity in the absence of chemical sensitisation. It has recently become possible to similarly include microspheres in LDAN (low density ammonium nitrate). Further to previous studies and publications to determine the benefits resulting from the use of microsphere enhanced LDAN technology in blasting, additional advantages are described in this document. These include range tests at independent testing facilities (Universal Tech Corporation û USA) which reflect results observed in the field, and support theoretical assumptions made when the products were introduced. Additionally, on-site studies in opencast pits using Heavy-ANFO blends incorporating modified LDAN, show that monetary savings can be realised through significant advantages gained in plant throughput and explosives use.

Jan 1, 1999

By M D. Boscardin, P A. Roy

The North Shore Connector Project for the Port Authority of Allegheny County involves TBM tunnelling twin light rail tunnels through cohesive soils and rock under the Allegheny River and a narrow city street. Along the tunnel alignment are a listed historic building on shallow foundations as well as modern buildings on deep foundations; one major office block was actually constructed directly over the alignment during the latter phases of design process. This paper provides an overview of the general site conditions, tunnel design and the technical basis for excavation support and tunnelling decisions. Deformation limits, ground improvement, monitoring and mitigation plans are also discussed. Project construction has now commenced and a brief summary of progress to date is included in this paper; this will be updated for the presentation to be made in Melbourne.

Jan 1, 2008

By Van Rooyen F

An introductory review of the current grade control blasting techniques (selective mining strategies) used in the Eastern Goldfields has recently been undertaken. The survey was initiated and conducted by the Western Australian School of Mines. Four distinct selective mining strategies have been identified and a number of trends have been highlighted. Many operations, however, have developed techniques which use a hybrid method to suit the site conditions. The aim of all the mining strategies is to produce an optimum product. The optimum product is one which contains no diluent and experiences no mixing of the various identified ore and waste blocks and is fully reco- vered at the minimum overall operating cost. Due to this unified aim all of the grade control blasting techniques have many common design Features.

Jan 1, 1988

By L Soares, W T. Hennies, F Fujimura

A methodology of environmental performance evaluation in mining developments is proposed, as well as guidelines and procedures for obtaining information to improve their environmental performance. Environmental performance is the results of the mining activities and their relation to environmental issues. If this evaluation is carried out on an on-going basis, it is possible to anticipate or to identify the formation and development of an environmental impact in its early stages. Evidence or trends identified by environmental evaluation provide valuable information to prevent further damage. The proposed methodology is based on the significant environmental aspects of a selected monitored job site by environmental indicators which are then compared with previously defined environmental criteria and targets or goals. The methodology procedures also take into account the environmental accounting of the investments and expenditures.

Jan 1, 2003

With increasing depth of mining, geotech nical factors assume increasing importance in the design and operation of open pit coal mines. Dragline strip mines are particularly sensitive to stability conditions since the draoline is a relatively inflexible machine, particularly in relation to its limited dump- ing radius for overburden disposal. Geotechnical factors relevant to strip mine design include: 1. spoil pile stability 2. wall stability 3. floor stability 4. excavation characteristics 5. groundwater conditions A basic geotechnical investigation pro- gram for new mine feasibility studies is described. This includes: 1. terrain evaluation 2. geotechnical drilling and logging 3. geophysical logging 4. materials testing 5. seismic refraction traversing 6. groundwater studies Such a program will give an overall geotech- nical assessment of the site and highlight any areas which may require further, more detailed Investigations

Jan 1, 1981