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By Maidl B

A tunnel operations analyser is a new high technol- ogy instrument for use in underground work. By remotely sensing the acoustic emissions from operating machines and processes in a tunnel or shaft and by applying sophis- ticated computer processing to them individual process cycles and other detailed information about the operating processes can be collected. Detailed analyses and dissec- tions of the work in progress can be made and a variety of action oriented management reports produced. The pro- cess is fully automatic. Results of applying this device to two full scale tunnel projects are presented. The hardware and software that comprise the instrument are discussed in detail. Processes by which this device can be used to sub- stantially reduce tunnel costs are presented. It is concluded that this type of technology has great potential.

Jan 1, 1987

By A van As

This paper serves to outline the circumstances and causes of the air-blast that occurred at Northparkes Mines in November 1999. It describes the design of the mine, the geotechnical issues surrounding cave propagation and the cave monitoring systems that were in place prior to the event. A short description of the air-blast that followed a sudden collapse is given. Details of the risk assessment process that evolved during the rectification process are provided with their subsequent modification to form the core of a major hazard monitoring process. The system is in line with the recommendations given by the Coroner resulting from the inquest into the deaths of the four people who lost their lives during the air-blast.

Jan 1, 2005

By J Arif, J Proffett

Copper and gold mineralisation at Batu Hijau is directly related to quartz veining and wall rock alteration that developed in close spatial and temporal association with multiple tonalite porphyry intrusions. To its advantage with respect to the study and better understanding of the evolution of the porphyry system, Batu Hijau has comparatively minor late alteration and mineralisation overprints. This paper summarises results of detailed geological logging, petrographic studies and geochemical analyses of diamond drill cores from the deeper sections of the Batu Hijau porphyry system (ie its roots). An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By J G. Webster-Brown

The Tui Mine is located near Te Aroha at the base of the Coromandel Peninsula. It was a lead-zinc mine, which closed in 1973 due to declining concentrate prices, high overheads, and high mercury levels in the ore. The site was abandoned, leaving behind an acid rock drainage generating system, including a sulfide-rich tailings dam which has since caused pollution of Tui Stream, as well as open adits and waste piles which drain predominantly into the neighbouring Tunakohoia Stream. At the AusIMM conference in 2003, Harvey and Webster-Brown presented water quality results from the Tui mine site and lower stream catchments in 2002. In April 2006, Environment Waikato undertook remediation works to stabilise the dam and reduce acid drainage entering Tui Stream. In this study, water quality results from the Tui mine site and lower stream catchments are again being determined, in order to compare with the pre-remediation results. Preliminary data collected for summer indicate a minor but consistent improvement in water quality in the lower stream catchments, although lower Tui Stream continues to exceed ANZECC (2000) aquatic life guidelines for Cd, Cu, Pb and Zn. This slight improvement may be due to a decrease in the flow of ARD into Tui Stream, as there does not appear to have been an improvement in quality of the contributing ARD waters.

Jan 1, 2007

By Hill G

The Boddington Gold Mine (BGM) is managed by Worsley Alumina Pty Ltd (Worsley) and is located 110 km south-east of Perth, Western Australia. The gold mine, which has operated since mid-1987, was originally constructed to treat 3 Mtpa of gold bearing oxide ores, has subsequently been expanded to treat 7 Mtpa and is presently one of the largest gold producing operations in Australia.During 1990 a Supergene/Basement Plant was constructed to treat 250 000 tpa of copper supergene and hypogene ores and basement ores which contain significant gold grades and which are encountered at the lower levels of the existing oxide orebody. The SupergeneBasement Plant has the versatility to treat a wide range of ore types, producing both gold bullion and copper-gold concentrates. It is a stand-alone facility adjacent to the existing 7 Mtpa gold plant.

Jan 1, 1992

By S J. Clarke, G Sieders

Double corrosion protection (DCP) rock bolts have evolved to become complicated assemblies comprising numerous components. This complexity is mainly associated with durability considerations including potential exposure to adverse groundwater conditions and ensuring separation of dissimilar metals within the bolt assembly itself.Recent progress in the construction of glass-fibre reinforced polymer (GRP) rock bolts have the potential to provide a viable alternative to conventional steel rock bolts in civil tunnelling applications. The durability of the material results in a much simpler bolt detail and permits the use of resin rather than solely cement based grouts.This paper presents the findings of the comparative structural testing of GRP bolts with conventional DCP steel bolts. The axial load performance, including stiffness, ultimate capacity and ductility of bolts are compared. Shear behaviour of bolts is considered, including durability issues associated with damage to the plastic sleeve used in DCP bolts.The paper also considers other issues which are relevant to the design of temporary and permanent rock bolts used in tunnel support, such as initial tensioning and grouting. Long-term performance, including durability and creep are also reviewed.CITATION:Clarke, S J and Sieders, G, 2014. Comparison of glass-fibre reinforced polymer rock bolts with double corrosion protection steel rock bolts for use in tunnel applications, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 237–246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By English W, Poppit I

COALEX Pry Limited operates two underground steaming coal mines on the western edge of the Sydney Basin near Lithgow, New South Wales. Baal Bone Colliery uses longwall technology for an output of over two million tonne/year while Clarence Colliery currently uses continuous miners and breaker line supports for an output of two million tonnelyear.A computerised geological database and modelling system has been implemented to service these mines routinely, as well as several outlying prospects. The database is constantly upgraded for drillhole information, surveyed spot levels on the surface and underground, quality sampling details, surveyed mine workings and geological mapping. This information is edited on a routine basis, allowing dynamic modelling of key aspects of geology for ongoing operations.

Jan 1, 1991

By Harvey T, Kizil M, Bride J

Hydrogen sulphide (H2S) as a seam gas has occurred in several locations in the German Creek seam at Southern Colliery. This paper overviews the techniques developed to quantify the H2S content of the seam, overviews research into controlling and reducing H2S emissions from the seam, and details the procedures used to mine through the HZS zone in 702 longwall panel. Learning points from research and mining experience are reviewed for application in the next longwall block.

Jan 1, 1998

Arrow Energy NL has been operating a number of coal seam gas wells in the Darling Downs region of Queensland. At the time of writing this paper, the region is enduring an extended drought period. The local aquifers are depleting and have not been significantly recharged in over a decade. The local communities (both rural and townships) are struggling to obtain water. Currently, coal seam gas (CSG) operators (under licence) draw water from the coal seams as part of the gas production process and the majority of operators choose to evaporate this water, as it is characteristically brackish to saline in quality and as such must be contained. Although the water produced from one CSG operator is not sufficient to drought-proof the greater area of the Darling Downs, there is potential to supply smaller local areas and contribute to the sustainability of these communities. This paper outlines the work completed by Arrow and its local community partners on the Darling Downs to date, and discusses the application of the produced formation water for:stock watering in feedlots, as a feedstock for coal washing, as a potable water supply for Dalby, as an agricultural water supply for cotton farming, and use as a medium for growing salt-water fin fish.

Jan 1, 2006

By Osorio J. D C, McMahon M. D

Burwood Beach Sewage Ocean Outfall is being constructed by the Hunter District Water Board as part of an amplification scheme to eliminate pollution from adjacent bathing beaches. The outfall consists of a 93m vertical shaft, 1950m of 2.7m diameter tunnel with a series of diffuser outlets connecting the seaward end of the tunnel to the sea floor on a rock outcrop. The site of the work is in the Newcastle Coal Measures and the project is complicated by the proximity of colliery workings to tunnel alignment, although the colliery records provided valuable information on geological features. The location of the tunnel was determined to be in the Waratah Sandstone Formation immediately below the colliery workings after three different alternatives were considered. The shaft, which will be sized to suit contractor's construction methods and equipment, will be sunk through about 24.5m of alluvial material and 68.5m of rock. The tender documents were developed to allow the contractor considerable flexibility in construction method to suit available equipment. The specification also allowed great flexibility in tunnel construction method with minimum cross sectional area of 5.7m2 being the basis for a number of allowable alternative profiles ranging from circular to horseshoe.

Jan 1, 1987

By Enever JR

In-situ rock stress measurements conducted in the Phillipines and on Bougainville have revealed stress fields significantly different from expectations based on intraplate experience. The results have potential significance in regard to both engineering practice in the Pacific Rim region as well as in helping to understand the geological processes occuring near subduction Zones.

Jan 1, 1987

As partition curves are widely employed to characterize screening efficiency which, by definition, should include a time parameter, it is shown, perhaps for the first time, that time is already included in the partition curves and how. Laboratory and plant results are used to show how screening efficiency depends on feed composition, near-mesh and oversize material and screen motion, and how these factors may combine to give an erroneous result that two identically efficient screens are different and two screens of different efficiency are identical. Reasons are given which show why a renewed interest in screening would benefit not only screen engineers and operators but also those concerned in formulating standard specifications of screen analysis methods.

Jan 1, 1984

The future of the United States (US) mining industry will be affected greatly by recent coal mining disasters. These have resulted in new legislation which will have an impact on mining economic costs as well safety and health of miners. This paper discusses the changes that new legislation and regulations are making to the industry and current research that is producing technologies to make mining safer and will likely impact the future of mining.

Jan 1, 2008

By Mahoney BK

The development of simulation models to reflect accurately the operations of a port and its associated transportation systems can be an expensive and time consuming process. However the complexity of such operations leaves little choice for other than simulation techniques since analytical methods are rarely appropriate. The development of suitable software has now reached the stage that these techniques can be used with confidence. Types of simulation models and their requirements are discussed together with the results from some recent applications to the planning and management of bulk terminals.

Jan 1, 1983

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 Bureau of Mineral Resources has been engaged in regional geological and geophysical field work in the Alligator River and Cobourg Peninsula area since 1971, following the discovery of major uranium deposits. Geophysical work commenced with a regional airborne magnetic and radiometric survey which was followed up by some helicopter and ground work in August 1973. The interpretation of the earlier radiometric work is presented in conjunction with the results obtained from the follow-up work. Analyses of 100 outcrop and drill core samples collected have provided basic information on the physical properties and concentrations of uranium and thorium in various rock types. The uranium determinations were made by X-ray fluorescence and delayed neutron analysis, good agreement being obtained between the two methods. X-ray fluorescence was the main analytical technique used because of its ability to produce both uranium and thorium determinations.

Jan 1, 1975

By Guo-Zheng J

This paper describes the risk management strategies adopted to control unstable slopes in the east open pit of the Daye iron ore mine. Extensive experience has been developed over the last 35 years in the management of pit wall instability resulting in the successful excavation and reinforcement of pit slopes over 350 m in height.

Jan 1, 1994

The statistical nature of the variability in detonation times of pyrotechnic delays is discussed, and how to evaluate the probability of required detonation intervals is shown. Some methods (analytical and stochastic) are given for designing blasts to ensure that any adverse effects on the variability in the delays is taken into account and minimised. Using computer models of blasts, detonation simulations can be used to check the initiation sequence for the probability of sequence reversals, indicating areas of high blast damage potential. Charge consumption rates, which relate directly to the resulting vibration levels, can be examined for their susceptibility to variation from delay variability. Models that synthesize vibration waveforms for production blasts, when taking delay variability into account, indicate the difficulty in vibration level prediction.

Jan 1, 1992

Laboratory studies of batch and continuous screening of ferrous sinter mixtures (4-0.5 mm) are described. The results are analysed by an equation derived from the first-order rate law for the condition of decreasing screen residue.The results of the studies show that the two screening operations are comparable in all respects if deck length in continuous screening and time in batch screening are interchanged.It is shown that the general screening process is determined by the numerical values of the screening rate constants of each of the particle sizes in the feed mixture and that the relationship between these constants and the particle size/screen aperture ratios is related to the appropriate probability function of the same ratios.It is also shown that the screening rates decrease exponentially with the amount of near-mesh material present in the feed and that oversize particles can increase these screening rates for some screen motions and decrease them for others.

Jan 1, 1985

The scarcity of truck tyres combined with decreases in the availability of labour, increases in fuel costs and a buoyant international economy driving project budget blowouts, have all combined to change the paradigm behind mining equipment selections. The escalation of commodity prices has occurred in parallel with an increasing maturity in continuous mining machinery, mobile in-pit crushing systems and very large-scale conveyor belt systems. This paper will consider the merits of operating continuous materials handling systems, mobile in-pit crushing systems, relocatable crushing systems, relocatable conveyor systems and automated waste handling systems in place of the more conventional approach of truck haulage.

Jan 1, 2007