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By Windsor C. R, Thompson A, Bywater S

A new high tensile strength, steel cable, that may be grouted into boreholes has been developed for use as rode reinforcement. The manufacturing technique produces a birdcage pattern in which the cross section varies along the length of the cable. The load transfer from cement grouts to birdcage cables has been demonstrated in laboratory tests to be better than that of standard 15.2 mm diameter seven wire cables. The manufacturing process also allows for a wide range of capacities which may be specified by design engineers. The various birdcage cable configurations have been applied as rock reinforcement in a number of Australian underground and surface mines.

Jan 1, 1990

By Szymanski J

Although efforts towards producing a `total quality rockfill product' have allowed cemented rockfill costs to be reduced considerably, there is still tremendous potential for further cost reductions. Cemented rockfill costs range from approximately $7 to $12 (US) per tonne of fill placed. Approximately 50 per cent of the rockfill costs are associated with cement costs. A large portion of the remaining 50 per cent is associated with labour and materials handling costs. Several Canadian underground mines utilise haulage trucks and/or conventional belt conveyors to distribute the rockfill. However, due to the restrictive nature of the underground environment, these current materials handling systems have limitations (ie spillage from trucks, dust from conveyors). The Sicon conveyor system (developed in Sweden) has considerable potential for replacing these current methods. The Sicon conveyor utilises a revolutionary approach - the conveyor belt is folded over upon itself (forming a tear drop shape) so that the transported material is completely encased within the belt. The Sicon conveyor's ability to negotiate very tight comers (without transfer points) makes the conveyor very appealing for underground mining applications. An analysis comparing the pros and cons associated with the Sicon conveyor system versus conventional materials handling systems will be presented in this paper.

Jan 1, 1995

By Chenggang W, Junhua D

Fragmentation variation laws in loading and non-loading areas are obtained by cement block model blasting experiments under various stemming lengths. A reasonable ratio between loading length and stemming length is worked out according to minimum average fragment size. The present continuous loading structure, for its very long length to be stemmed, leads to insufficient fragmentation in the upper part of bench. So a new loading structure with bottom air cushion is put forward. The author analyzes blasting effects and processes of two loading structures' and proves that there exists a optimal length of air cushion.\

Jan 1, 1990

Limnological processes are often overlooked when trying to assess the long-term water quality of pit lakes. It is essential to deal with these aspects, since they determine the geochemical and redox conditions around the submerged reactive rocks. Underground mining at East Sullivan (northwestern Quebec, Canada) stopped in 1966. Two adjacent stopes, 91 and 106 m deep, were left open to the surface, with roughly circular apertures of about 7700 and 18 000 m2. Water filling of the two glory holes went on over three decades and overflow began in 1999. Surface water pHs values were near neutrality as late as 1994 (6.3 - 7.0) but had become acidic by 1999 (2.6 - 3.5). Limnological processes were investigated in late-1999 and early-2000, with temperature measurements at 1 m intervals and sampling of the water columns before and after the late fall density inversions. A strong chemocline-thermocline was observed at 15 m. Above the chemocline, the water had low pH (3.2), no alkalinity, and low Na, Ca and sulfate. Below the chemocline, the concentrations of these parameters and the pH increased, with pH at 5.5 - 6. Consistent with the low pH values present in the upper 15 m, the concentrations of Al, Cd, Cu, and Zn were high near surface, and decreased below the chemocline. Dissolved oxygen concentrations as well as Eh decreased with increasing depth. Alkalinity integrated over the entire water column below the chemocline was at least six times larger than the acidity inferred from Fe2+ and Fe3+ concentrations. The temperature survey showed that seasonal density inversions do occur in the water column. The inversions do not involve the entire water body, since the surface to depth ratio is too small for a complete overturn. Oxygen from surface waters is carried to the bottom where it oxidises sulfides, until its depletion. Residual Fe2+, stable under anoxic conditions, is displaced upward by the next dense water incursion. It eventually reaches the thermocline, but only after many successive incursions. There, its oxidation to Fe3+ allows hydrolysis, which consumes dissolved and wall-rock alkalinity. It is only in 1999 that alkalinity was finally exhausted and that the pH shifts to acid values. The low pHs in the surface waters allow a build up of Fe3+ and Al3+, and desorption of metals from colloids. Buffering is assumed to be controlled by wall-rock oxyhydroxides in surface waters, and by carbonate minerals in the bottom waters. Because the seasonal overturns are far from being complete, the large amounts of alkalinity acquired from the wall-rock in the bottom waters cannot balance the acidity of near surface waters. Hence the surface water is acidic.

Jan 1, 2003

By Dredge K, Becker G

The successful dissolution of the valuable metal components of a solid phase is often a basic requirement for a successful hydrometallurgical treatment process. Sulphide concentrates are often an intermediate product in the production of refined metals. These concentrates need to be further processed to realise the contained metal values in a useful form. Pyrometallurgical techniques have tended to dominate, at least the initial treatment of metal sulphide concentrates. The technology described, Activox«, has been developed specifically for the hydrometallurgical treatment of these sulphide mineral concentrates, in particular those containing copper, nickel or gold. The Activox« dissolution technology coupled with the use of existing, or newly developed, downstream processing techniques, offers alternative processing options for the recovery of full value, saleable metal products. The technology is suitable for application down to relatively small scales opening up the opportunity for on-site production of metals even at modest scale mining Operations.

Jan 1, 1995

By D H. Bell

Slab-buckle failures in coal sequences involve thin slab deformation in strata dipping parallel to the footwall, and are a consequence of both unloading and the weak nature of the thinly bedded rock mass. Methods of modelling and predicting such occurrences include: +        a conceptual model using a base friction table, +        a mathematical model using the Euler solution for column and beam bending (after Goodman, 1980), and +        computer analysis techniques such as UDEC (Universal Distinct Element Code after Cundall and Hart, 1993).   Slab-buckle failures have the potential to seriously disrupt production because of their volume and rapidity, and to endanger both equipment and personnel working on the pit floor.   In July 2004 a large slab-buckle failure occurred overnight after a new batter and bench had been formed at the Malvern Hills Opencast Mine in inland Canterbury. This involved the entire length of the pit (85m along strike) when a 2m thick intact slab with a total volume of ~3500m3 translated down dip 6.2m on the base of a thin coal seam to form a pronounced buckle at the toe. The coal measures consist of finely laminated mudrocks with multiple coal seams of varying thickness dipping ~45¦ to the southeast, and the opencast mine had been designed with footwall batters formed parallel to bedding with a vertical bench separation of 15m.   Back analysis of the Malvern Hills failure was necessary to investigate the controls on footwall instability, and for future mine design. An engineering geological model was created and samples of the slab material and failure surface were collected and tested to establish the required parameters for use in the Euler solution for column and beam bending. Back analysis using the Euler solution provided unrealistic results that overestimated the overall length of a stable slope by more than 10 times.   No further large scale slab-buckle failures have developed at the mine site, in part because of the slow rate of coal extraction, but precautionary drainage of the footwall slopes has been undertaken to improve overall batter stability. The location of the slab-buckle failure on a critically positioned pre-sheared thin coal seam with full hydrostatic head is considered the most probable cause of the July 2004 failure, rather than inherent instability of the generic bench and batter arrangement adopted. The use of a precedent-based engineering geology approach to future mine design is considered the most appropriate solution in the circumstances.

Jan 1, 2007

The extinction of zinc from steelmaking dusts has been studied with a laboratory scale reduction-vapour deposition (RVD) process in the absolute pressure and temperature ranges of 13 - 1300 Pa and 1333 - 1513 K respectively. This process consists of pre-reduction of iron oxide by carbonaceous agent, carbothermic reduction of zinc oxide under reduced pressure to produce zinc deposits and subsequent re-evaporation of the deposits to liquedify the zinc. In the RVD, the gas mixture of Zn and CO quenched from the hot zone is separated into Zn deposit and CO which is transferred to the pumping system. The Zn are a layer of fine metallic zinc powders accumulated on the cold wall and removed to the vacuum distillation chamber. The experimental works have been carried out according to the following items: carbothennic reduction of zinc oxide under vacuum, carbothermic reduction o zinc ferrite under vacuum, and 3. distillation of the Zn deposits. It has been concluded from these experimental results that the recovery of metallic zinc from the EAF dusts is successful by this process, and a new concept for a practical zinc winning process has been proposed.

Jan 1, 1993

By Mizuta T, Sakurai M

The Pine Creek Inlier produced 12 440 kg of gold in the period from the first gold discovery in the 1860s to the early-1900s. During the 1930s renewed large-scale prospecting took place and gave a foothold for today's gold mining operations. The rise of the gold price and improved mining methods in the 1970s and 1980s made possible low cost, bulk low grade mining operations. Various gold deposits including vein, network and stratiform types occur in the Pine Creek Inlier (Nicholson and Eupene, 1990). The Tom's Gully deposit is located 100 km south-east of Darwin in the Northern Territory. It is hosted in the early Proterozoic Wildman Siltstone and lies north-east of 1800 my old Mt Bundey Pluton (Figure 1). Around the Mt Bundey Pluton, there are several prospective base and precious metal deposits such as Quest 29. The Tom's Gully gold deposit was discovered in 1986 and yielded a total of 3070 kg of gold from ore averaging 9.35 g/t gold between 1987 and 1990 when the mining operation was terminated.

Jan 1, 1994

The present Pacific Ocean arose from rapid sea-floor spreading that commenced in the late Mesozoic, and continues to the present day. It started within what is here called the Medusa complex of seaways, basins and troughs with spreading ridges and volcanic arcs, that girdled the earth, including the Palaeotethys and Neotethys of Eurasia between Gondwanaland and Laurasia. Detailed mapping and analysis of palaeofaunas and volcanic arcs indicate that several seaways, rather than one or two, extended throughout Tethys, and into areas now occupied by the Pacific Ocean. The Medusa complex developed under a long sustained wrench regime, right lateral at least from New Zealand to Eur.ope, and saw the origin, maturation and closure of elongate and oval basins under erratic sea-floor spreading, in which no Eulerian pole of rotation remained fixed for long. The name Medusa stems from the analogy of snake-like writhing hair to the constantly shifting development of basins and orogens within the complex. The Indian Ocean split and opened up Gondwanaland concomitant with the later development and deformation of the Tethyan segment- of Medusa, whereas, to the east, the Pacific Ocean opened within Medusa itself, and dispersed Medusa around the rim of the Pacific through sea-floor spreading and strike-slip faulting.

Jan 1, 1987

By Schiller J. C, Both R. A

Base metal mineralisation occurs at several locations within the regionally metamorphosed Kanmantoo Group on the southeastern flank of the Mount Lofty Ranges between Kanmantoo and Strathalbyn, 50 km southeast of Adelaide. Sulphide mineralisation is of three main types (Seccombe et al, 1985):1. copper deposits, at the Kanmantoo and Bremer mines, South Hill prospect and several minor occurrences,2. lead-zinc deposits at Aclare, Wheal Ellen, Strathalbyn, St. Ives, Scott's Creek, and Glenalbyn mines,3. pyrite-pyrrhotite mineralisation of the Nairne pyrite deposit and many other pyritic schist units within the Kanmantoo Group.Syntheses of folding, metamorphism and stratigraphy of the Kanmantoo Group were given by Kleeman and Skinner (1958), Offler (1960, 1963), Offler and Fleming (1968), Marlow (1975), Mancktelow (1979) and Parker (1986). Studies of the general relationships of mineralisation to structure in the Kanmantoo area were given by Grasso and McManus (1954), Mirams (1962), Poole (1969), and Lindqvist (1969).Several conflicting views on the origin of mineralisation in the Kanmantoo Group have been proposed. Thomson (1975) considered much of the mineralisation as a late-stage product of regional metamorphism and he, like Parker (1986) and Lambert et al (1987), stressed the importance of major lineaments as an ore control. However, Lindqvist (1969) and Verwoerd and Cleghorn (1975) tentatively suggested a syn-sedimentary origin to the Kanmantoo copper deposit and Jensen and Whittle (1969) and Seccombe et al. (1985) on the basis of sulphur isotope data proposed a bacteriogenic sulphur source and a sedimentary origin for sulphides in the Nairne pyrite deposit. The latter suggested that most copper deposits represent stockwork, vein or disseminated zones within subsurface vents whereas massive mineralisation at Wheal Ellen and Aclare mines probably accumulated on the ocean floor.This paper presents new geological information on the structural and metamorphic setting of the base metal deposits and attemptsto relate this information to previous regional studies of the Kanmantoo Group. Estimates of pressure and temperatureof peak metamorphic conditions based on silicate mineral stabilities are considered in relation to various silicate and sulphidegeothermometers which have not previously been applied to rocks in the Kanmantoo Group.

Jan 1, 1988

The Hail Creek coking coal deposits are situated in Central Queensland, inland from the port of Mackay. A joint venture of Australian and Japanese companies has been formed to examine the feasibility of developing these deposits for sale on the overseas markets. The project envisaged involves large scale mining operations and on site benefic- iation to wash the coal to marketable quality. Infrastructure items include a 140 kilometre railway to the coast, a port facility, and at Ilail Creek, power and water supplies, roads and communications, and accommodation for a substantial workforce. The need for town development and the responsibility for the development are established. The town planning implications of coal production at the rate of five million long tons of washed coal per annum from open cut and underground mines are considered. A procedure for estimating the size of the town is expounded and the town size is determined. The factors influencing site selection are explained and a site is suggested. A method of designing the town is described and comments are made on developmental aspects. Spaciousness and preservation featuring the natural environment will be the theme of the town development.

Jan 1, 1973

By A G. L Pratt

Operational readiness is a commonly used term in mining and many other industry settings. However, translating this term into a coherent scope of work that is practical and meaningful is a challenge faced by many mining projects. This inhibits the allocation of resources to the work and its completion. The problem is with understanding how the terminology applies to establishing a mining operation. Resolving this problem requires clarity around what operational readiness means for a mining project’s transition to operations and who owns the tasks of completing operational readiness. The motivation for resolution of this problem is in appreciating the consequences arising from any lack of clarity in definition of this task, the timing of the work, and ownership for its completion. In broad terms, these consequences amount to an erosion of value at a critical time for both the new mine and the company and shareholders. This situation often arises where operational readiness is not adequately addressed in project’s study phases. As a result, neither time, resources nor money are adequately provided to complete the work required. In other cases, operational readiness is sometimes assimilated with the delivery of the project’s physical assets by the project’s construction team, rather than aligned with the establishment of the operating team to deliver the desired operational outputs. This paper argues that operational readiness starts in a project’s study phases and flows through into the start of operations. The definition of operational readiness is discussed as a task, and a model for its planning and completion is presented. This discussion includes assigning ownership for operational readiness planning and delivery to the General Manager of a new operation and the operations leadership team, who are central to the success of this work. After all, the reputations of this leadership team depend on the performance of the operation in its first few years. The author’s work over the last 20 years, leading operational readiness programs and the preparation of feasibility studies for mining projects, has provided the insights and evolution of ideas that are central to this paper. Operational readiness is fundamentally directed at ensuring a new mining operation gets away to a successful start and builds a solid foundation for the future of the mine/operation/province. It requires clarity of purpose, ownership and coordination by people in the operating team, and their preparation of the requisite process definition and establishment of the significant relationships required for operations. Without its successful completion, it is unlikely the new operation will meet and sustain its start-up targets. This paper discusses a practical approach to operational readiness for mining projects.

Mar 29, 2023

By R Bunduwongse

The oil crisis had repercussions throughout the world and most importantly on mining, where the drive to reduce the use of liquid fossil fuel led directly to the appearance and subsequent growth in the design of mobile crushers in late 1970s early 1980s, which heralded a new era in both quarrying and mining. Even though mobile crushing has now become common, even preferred in the quarrying industry, this has not been the case in mining. This paper looks at why, in spite of the initial optimism, this technology has yet to gain full acceptance in the mining industry. The paper examines some of the problems that have been encountered in the past and offers suggestions as to how they can be avoided by applying the appropriate technology. It then takes a look at the successful application of the semi-mobile in-pit crushing system used by Italian Thai Development Company (ITD), on the Mae Moh Phase 5 contract and examines how the techniques used successfully there could be applied to the industry at large.

Jan 1, 2007

By B Saunders, J Carpenter

PanAust’s Phu Kham copper-gold operation (Phu Kham) in Laos is currently limited by throughput in the Semi Autogenous Grinding (SAG) mill. The ability to accurately predict SAG mill throughput (throughput) is therefore critical to accurately forecast copper and gold production. During the fourth quarter of 2016 the proportion of hard unweathered rocks in the mill feed increased, resulting in a period of lower than expected throughput. These low throughput rates prompted a study with the aim of identifying a practical solution for throughput predictions. The study identified an empirical modelling approach based on actual SAG mill throughput rates. The empirical model was then optimised by linear programming to identify the ideal feed blend of unweathered rocks to achieve a maximum SAG mill throughput.Rock strength was the initial focus of the throughput study at Phu Kham because previous studies had identified a strong link between rock strength and throughput. It was determined that there was insufficient valid data to adequately model but sufficient data to qualitatively characterise rock strength. The data identified that the weathering and lithology had a controlling influence on the rock strength. Complicating throughput predictions were operational improvements (changes to blasting and mill settings) implemented in response to the lower than expected throughput. This created uncertainty with the throughput equations. A self-learning empirical modelling method was developed to predict the throughput by incorporating fundamental rock properties with operational practices and improvements. The method is based on the proportion of mill feed with similar weathering and lithology (a proxy for comminution performance) and the actual mill throughput using the SAG mill as the analytical instrument. The modelling method simultaneously incorporated the sum and interaction of unmodelled influences including blasting, crushing and mill settings. The empirical modelling method worked at Phu Kham because the lithology and weathering has an intuitive and observable controlling influence on SAG mill throughput. The modelling method is described along with a worked example of feed blend optimisation using linear programming.CITATION:Carpenter, J and Saunders, B, 2017. Empirical mill throughput modelling and linear programming for blend optimisation at the Phu Kham copper-gold operation, Laos, in Proceedings Tenth International Mining Geology Conference 2017, pp 291–296 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By J Bang, I-H Jung

Ti is an important constituent for steels and superalloys. During the continuous casting process and ElectroSlag Remelting process (ESR), Ti in molten steel and superalloy can have chemical reactions with casting flux and ESR slag containing CaO and CaF2. In order to investigate such exchange reactions, the understanding of the (Ca,Ti//O,F) reciprocal slag system is prerequisite. In the present study, a coupled phase diagram experiment and thermodynamic modelling of the (Ca,Ti//O,F) reciprocal system was performed. In particular, the phase diagram of the CaF2-TiO2 system was experimentally investigated by Differential Thermal Analysis (DTA) experiment and quenching experiments followed by Electron Probe MicroAnalysis (EPMA) phase analysis. The Gibbs energy functions of all solid and liquid phases in the (Ca,Ti//O,F) reciprocal system were optimised to reproduce the present data and all available reliable experimental data in literature.

Jun 19, 2024

By A Giyose, V Malysiak, K Davey

Batch flotation tests were conducted on a haematite-bearing Sishen iron ore slimes sample from South Africa using reverse cationic flotation. The effect of grinding on flotation performance, the flotation response of various key impurities in the sample, and the feasibility of increasing metal recovery by refloating tailings in a scavenger flotation step were investigated. The test results indicate that reverse cationic flotation is effective in rejecting impurities from the iron ore sample tested. From a head grade assaying 6.4 per cent SiO2, 2.14 per cent Al2O3, 0.402 per cent K2O, 0.082 per cent P and 0.194 per cent TiO2, the levels of impurities were reduced to 1.83 per cent SiO2, 0.88 per cent Al2O3, 0.095 per cent K2O, 0.066 per cent P and 0.174 per cent TiO2 in the final concentrate at a Fe recovery of 74 per cent. The flotation response of SiO2, Al2O3 and K2O were found to be better than that of P and TiO2. The testwork demonstrated that grinding to 80 per cent passing about 49 microns is essential for upgrading the Sishen iron ore to produce >67 per cent Fe concentrate grade. This grind size corresponds to about 80 per cent liberation of haematite from the gangue minerals. Fe recoveries up to 76 per cent were obtained by refloating the rougher tailings in a scavenger stage, with little effect on the final concentrate grade. Size-by-size Fe recovery data obtained indicated that particles below ten microns were mostly lost in the desliming stage conducted prior to flotation whilst some reported to the froth by entrainment. Some of the coarser haematite-gangue composite particles reported to the froth product by genuine flotation.

Jan 1, 2009

By P Mugebe, M Yahyaei, M S. Kizil, R Low

This paper seeks to establish an empirical relationship between the impact of mining technological innovation implementation and a company’s market value. The company’s market value is represented by its stock price. In a bid to ascertain the relationship, a stock price prediction model is sought to be established using the firm-specific factors impacted by the implementation of innovative technology. This work is performed under the watch of the prevailing macroeconomic factors. The background anchors in the understanding that the difference between the economic status of a mineral deposit and its uneconomic status lies in the level of mining technological innovation most prevalent at a given time (Hartwick, Olewiler and Preuss, 1986; Wellmer and Scholz, 2017; Wright and Czelusta, 2003). This is derived from productivity improvement, resulting in sustainable profitability due to technological innovation. Unfortunately, there is not an adequately established relationship that links this technological innovation impact to the share price performance of the mineral commodity company.

Sep 1, 2024

By P Christen

The Ernest Henry Copper gold mine situated in North West Queensland, Australia, is owned and operated by Xstrata Copper. Currently the open pit produces 11 Mtpa of ore. With open pit mining ceasing in mid 2011 development has begun on an underground sublevel cave mine to extend the life of the operation by another 12 years. When completed the open pit will be 530 m deep and 1.5 km in diameter. The orebody dips at approximately 45° and has been outlined a further 450 m below the base of the pit. This provides some challenges for the Ernest Henry underground mine which is designed to initially truck development and production ore from the end of the pit until a hoisting shaft is commissioned in 2013. Production will then increase to 5.0 Mtpa on its way to an ultimate rate of 6.0 Mtpa in 2016.This paper will focus on the capital development and infrastructure requirements for the underground mine. Areas covered include mine accesses, ore handling system, accommodations for the dip of the orebody, primary ventilation design, dewatering systems and selection of an underground workshop over surface only maintenance.Discussions include the complications arising due to the mine being located directly below a large open pit and the combination of first principle cost analysis and risk assessment which has been used to safely optimise the feasibility study designs.

Mar 21, 2011

By J Pan, C M. Tang, D Q. Zhu, C C. Yang, S W. Li, Z Q. Guo

The short process of electric furnace steelmaking with direct reduction iron (DRI) as raw material is an important process for smelting high-quality and special steels. In order to prepare high-quality DRI, the pellets with basicity of natural basicity and 0.4 were prepared from magnetite concentrate (MR=0.09, MR=0.4) and hematite concentrate (HR=0.02, HR=0.4). Based on the HYL method, the gas-based direct reduction experiments were conducted under the condition of rich hydrogen (H2/CO = 2.6). The reduction index (RI), reduction swelling (RSI), cold compressive strength (CCS), and phase changes of the pellets were systematically studied. The results show that the RI of four kinds of pellets is greater than four in the temperature range of 800~950°C. For the magnetite pellets, at a fixed reduction temperature, the RSI increases and then gradually decreases, reaching a peak between 50 per cent and 80 per cent. Moreover, the RSI enhances with the increase of the reduction temperature. In general, the RI, RSI, and reduced CCS of the MR=0.09 pellets are better than those of the MR=0.4 pellets. For the hematite pellets, the maximum RSI decreases from 23 per cent to 17 per cent during hydrogen-rich reduction, while the compressive strength increases from 500 to 1070 Nꞏpellet-1. The main reason is that the glass phase generated by the increase of basicity adheres to the surface of hematite grains, hindering the contact between reducing gas and particles. As a result, the apparent activation energy is reduced, which is not conducive to the reduction process. In addition, the glassy phase attached to the hematite reduces the migration rate of Fe2+/Fe3+, resulting in a difference in the reduction expansion rate of hematite in the inner and outer layers of the pellet. Thus, concentric cracks are formed inside the pellets, the RSI increases and reduced CCS decreases.

Sep 18, 2023

By T J. Sullivan, H Pinkster, G Swarbrick

From 2002 to 2006, longwall mining was undertaken directly beneath the Cataract Tunnel, which is a 100-year-old, heritage-listed tunnel in Hawkesbury Sandstone responsible for delivering 20 per cent of Sydney’s annual water supply. At one location, undermining resulted in movement of at least 350 mm along a known fault that transects the tunnel. During this movement, the continued operation of the tunnel was ensured through a careful system of planning, monitoring and management.Of key importance to the success of the operation was the use of advanced numerical modelling to guide operations at all levels, including feasibility assessment, pre-mine mitigation works, monitoring design, operation performance and post-mining condition. This allowed many aspects of the potential impacts to be explored, including joint movements, rock mass deformations and changes in permeability. A key challenge was to successfully model near-field influences on adverse geological structure due to very far-field effects. This paper explains the model’s conceptual development, calibration, performance and limitations.Modelling provided the confidence to manage the impacts of large mining-induced movement on key infrastructure and ultimately predicted fault movement accurately. The fault movement remains one of the highest ever recorded due to mine subsidence.CITATION:Swarbrick, G, Sullivan, T J and Pinkster, H, 2014. Longwall mining beneath critical infrastructure – prediction versus performance of the Cataract Tunnel, New South Wales, Australia, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 157–166 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014