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By M Grigorescu, J H. Hodgkinson, H Alehossein

A new framework that collates and interprets pre-existing data to assess vulnerability and ultimately plan to avoid or minimise flood-related risk to infrastructure, people, downtime, environment and revenue has been developed. The æClimate Related Adaptation from Terrain Evaluation ResultsÆ (CRATER) method tested at a coal mine in Queensland, provides semi-quantitative information to assist decision makers when designating investment for minimising vulnerability of mining operations to climate. Here we present the processes involved in this three-step approach that uses pre-existing spatial data of the mine site and local knowledge to build a set of visual tools to assist decision-making. The first step of the process is performing multi-criteria evaluation (MCE) within a geographic information system (GIS) on ranked natural conditions at the mine, such as elevation, slope, drainage, soil and vegetation, which is performed to identify critical flood areas. Secondly, a fault-tree analysis identifies how impact can occur and what options there are for impact reduction. Finally, a resource assessment of the mineÆs capacity to adapt reduces the adaptation options to those most suited to the mine. The results are confidential, but for the purpose of introducing the methodology, we present simplified results, particularly of steps 2 and 3. CRATER can also be used for future æwhat-ifÆ flooding scenarios to identify the most suitable locations for roads, buildings or other critical infrastructure. The methodology is transferable to any mine, series of mines or locations along the mining value chain that have sufficient data, providing a practical decision-making tool to identify æno-regretsÆ actions that not only could reduce downtime after or during an event, but in some cases may enhance production between extreme events. We now plan to test this method at a broader scale, to encompass more than one mine in the analysis.CITATION:Hodgkinson, J H, Grigorescu, M and Alehossein, H, 2013. Climate Related Adaptation from Terrain Evaluation Results (CRATER) - interpretation of pre-existing data for mine site flood vulnerability and management, in Proceedings Water in Mining 2013 , pp 259-266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Leahey T. A

The variability of gold mineralization in the Warrego Gold Pod is described by classical statistical techniques using sample distrib- utions and analysis of variance; and by the use of geostatistical variogram analysis to define the spatial variability and anisotropy of the mineralization. Comparison is made between declared mine production from the Nineteen Stope and a series of ore reserve estimates derived by manual, numerical and disjunctive kriging methods.

Jan 1, 1979

By Whitworth N, Anderson P

New plant has been commissioned to treat off-gases from the Fluo-solids Reactor in the Copper Smelter. The new section of plant was built onto an operating system and commissioned with minimum disruption to production. Under construction is a 270 m tall stack for Lead Smelter gases. Additional items for the Lead Smelter will include a new gas cooler, a central baghouse to replace Sinter Plant wet gas scrubbers, a new exhaust fan on the main baghouse, and ducting of drossing gases to the main baghouse. Emphasis is given to discussing improvements the new plant has made to working conditions, the general environment and increased production capability. Total expenditure in the two smelters is in the order of $25 million.

Jan 1, 1978

By Brotzmann K, Turner RE, Philp DK, Rusden RC

New approaches in the last decade have led to the supplemental use of raw coal as a direct energy source in several iron and steelmaking processes. The dependence on more expensive coke and electricity is being progressively reduced. The Technology Venture of Klockner Werke and CRA has pionered several of these developments and is pushing ahead to processes for scrap melting and direct smel- ting of iron where coal is the ONLY energy source. Such complex developments depend strong- ly on the experience gained in the simpler but related processes for coal use already in operation. The longer term implications of a successful coal-based direct smelting process for the world steel industry are substantial.

Jan 1, 1986

By F Sinaga, E Widijanto

PT Freeport IndonesiaÆs Deep Ore Zone (DOZ) mine is the new underground block caving mine within the East Ertsberg Skarn System (EESS) which started production in mid-2000. The DOZ will produce 25 000 tpd using mechanised block cave mining method and will be the fourth underground mine opened within the EESS deposit. A review of the DOZ extraction bolting design was conducted in November 2000. The aim of this review was to re-evaluate the effectiveness of the current design in relation to bolt length and spacing and to challenge some questions about the technical background of the design. For instance, the influence of the rock condition on the design. To review this bolting design, several books and papers are reviewed and several experienced people have been contacted to give their opinion. The methodology used for this review is:reviewing the technical background of current design; collecting ideas and alternatives; collecting data from books and personal communication and conducting analysis; and conclusion and proposed design.

Jan 1, 2002

Among countries afflicted with insLantaneous outbursts of coal and gas, Australia is noteworthy because of lesser disturbances of the seams and of the occurrence of CO2 in the seam gas from place to place. Research sLarted with the 1954 occurrences at Collinsville and Metropolitan Collieries leading to early publications reviewing the problem, describing occurrences and assessing variations in proneness factors in the two affected coal basins.The basic requirements for proneness include coals of high gas sorptive capacity, high ground stress, use of a mining method which provides higher stress concentrations and limits emission of seam gas, including high rates of advance. With CO2 in the seam gas proneness is greater.The mechanism is complex and not fully understood, but involves the coal, the roof, the floor, the gas, the mine opening, the ventilation, the kind of work and the rate of work. Geological disturbances such as faults and dykes increase proneness and tend to localise occurrences. On-occurrence of outbursts in some mines is difficult to explain.Outbursts are seen as a continuing threat to modem deep Australian mining of high rank coal.The simplest contributory factor to reduce is gassiness - despite the low permeability of outbursting coals - and present practices are showing promise. The greatest challenges for the future are partial degasification to below a known threshold figure and confirmation that this reduction is achieved and identification of anomalous geological structures ahead, the most likely locations for instantaneous outbursts to occur. The advances made to date give promise of a future with reducing experiences of uncontrolled instantaneous outbursts. For the Bulli seam particularly, working to achieve prediction and prevention is most urgent.

Jan 1, 1993

By Bartosiewicz H

A method for the determination of the gas content of coal seams is presented which improves upon existing methods. The method makes use of a gravitational technique for measurement of the gas desorbed. The amount of lost gas is estimated by determining an empirical relationship relating the desorption of gas with time for each sample separately. This is to replace the assumption that desorp- tion follows a square root law with time. Laboratory investigations have been conducted which indicate that the square root desorption law does not hold good for carbon dioxide. Results of investigations on various factors influencing the technique are presented. It is shown that co-efficients of the empirical equation are dependent upon the elapsed time and the period of observation. Data about gas pressure measurements is presented and it is concluded that gas pressure can be approxi- mated to 0.6 times the pressure below a column of water equal to the depth of cover. This estimate is good enough for adsorption tests to evaluate desorption co-efficients. The technique for repressurisation of the sample,

Jan 1, 1982

By Hill KC, Foster DA

Methods for ore reserve estimation are classified. The amount of information needed to asses ore reserves is analysed. Reference is made to gold sampling. Consideration is given to nugget effects and ore reserve estimation procedures where they are significant. Computer methods are discussed

Jan 1, 1997

The McArthur lead-zinc-silver deposit is of the stratiform type. It consists essentially of a mineralized bituminous shale sequence that incorporates tuffites, numerous graded beds, and isolated but massive slump breccia horizons.The principal sulphides are' pyrite, sphalerite, and galena. These occur mostly in the shales. The accompanying turbidites contain only minor mineralization.The geochemistry of the deposit has been investigated in relation to the stratigraphic column and mineralogy of the sediments.A sedimentary origin is proposed for the deposit. Volcanism, thermal spring activity, salinity, regional faulting, and climate are examined as possible factors that may have contributed to sulphide formation and which could be used as criteria for mineral exploration.The metallurgy 'of the McArthur deposit is discussed in terms of its geological history.

Jan 1, 1972

By Smith N. S, Rholl S. A, Otterness R. E

The Bureau of Mines is conducting research to develop blast designs for the control of fragmentation and rock displacement and the reduction of overall mining costs. This Bureau experiment, a program of 25 reduced-scale blasts conducted at the University of Missouri-Rolla's experimental quarry, determined the effects on fragmentation of changes in burden, spacing, explosive diameter, and stemming-explosive length. Combined with previous work at this experimental quarry examining air gap, delay, and decoupling effects, this experiment provided a data base of over 50 shots. The fragmented rock, 1000 to 3000 kg from each 3- to 4-hole blast in the 1 m bench of massive dolomite, was completely screened to assess fragmentation. The explosive used for all the tests was extra dynamite initiated by seismic caps fired from a sequential blasting machine with delays of 5.2- to 13-ms/m of burden. Empirical equations were developed which predicted the effect of shot design parameters on the fragmentation. These formulas predicted the average fragment size of each of the 25-shots to within 13 percent. For spacing to burden ratios of 1, 1.4 and 2, there were optimum burden to explosive diameter ratios (B/de) of 30, 26 and 20, respectively. Decreasing the B/d. ratio beyond these levels resulted in little or no reduction in the average size. For B/de ratios above these levels the average size increased but, at least a 15 percent reduction in the average size results when the shot design parameters are optimized.

Jan 1, 1990

The eastern third of Australia contains an unrivalled Phanerozoic rock record generated by the regional interaction of Gondwanaland with the Pacific and by the global effect of the 400 m.y. Pangaea - Panthalassa cycle. Between the latest Proterozoic (600 Ma) breakup of Proto-Pangaea and the mid-Carboniferous coalescence of the dispersed continents in Pangaea, the Lachlan and Thomson Foldbelts accreted to the craton by Mariana-type (backarc basin) and Chilean-type (continental margin) subduction from eastward jumps of the Palaeo- Pacific rim. Further jumps of the rim of the Permian and Mesozoic Pacific, now expanded to Panthalassa, accreted the New England Foldbelt to the craton. An Early Permian rift basin was succeeded by a Late Permian to mid-Triassic foreland basin which extended between the craton and the foldbelt behind the 10000 km Panthalassan rim, from the Bowen Basin of Queensland to South America, and was host to the productive coal measures of eastern Australia, as the succeeding Jurassic and Early Cretaceous foreland and epicratonic basins included the coal measures, hydrocarbon reservoirs, and aquifers of the Great Artesian Basin. The magmatic arc on the Australian margin ended after the mid-Cretaceous uplift along the Queensland coast that initiated southwestward drainage from the high Pacific rim. The Chilean-type subduction that had prevailed since the Devonian was superseded shortly afterwards by Mariana-type subduction with the successive generation of the back-arc basins of the Tasman Sea, Coral Sea, and other southwest Pacific basins by the migration of the island arc to its present position 2500 km eastward of Australia.

Jan 1, 1990

By X Zheng, P Manton

Pebble recycle crushing circuit performance at Telfer has historically fallen significantly short of the design product P80 of 12 mm. An investigation was undertaken to evaluate the current pebble crusher circuit performance, quantify the optimum performance achievable with the existing circuit and examine the impact of pebble crusher performance on the overall grinding circuit throughput. The primary objective of this investigation was to develop an operating strategy that could consistently deliver the finest possible pebble crusher product to maximise the overall plant throughput.The pebble crusher specific energy (Wc) was proposed as a key control variable for pebble crusher operation based on the results of plant survey work. Over the range of pebble crusher specific energies encountered at Telfer, a strong linear relationship was found to exist between Wc and the crusher product size. This direct linear relationship between specific energy and crusher product size remained constant regardless of how the change in specific energy was generated, ie through changes to the crusher closed side setting (CSS), feed rate, liner profile or moisture content. Key findings for the Telfer pebble crushing circuit were: each 0.1 kWh/t change in Wc resulted in a 4.9 per cent to 6.0 per cent change in plant throughput, each 1 mm change in pebble crusher CSS resulted in a 2.2 per cent to 2.6 per cent change in plant throughput, and 0.57 tonne of new feed was displaced for each tonne of crushed pebbles recycled to the semi-autogenous grinding (SAG) mill. The presence of an existing 3000 tonne pebble stockpile between the SAG mill and pebble crushers provides an opportunity to manipulate the feed rate to the pebble crushers independently of the SAG mill pebble production rate. This flexibility, along with excess pebble crushing capacity, enables the pebble crusher specific energy to be maximised the majority of the time. Pebble crusher specific energy has subsequently been incorporated as an online crusher control measure to assist in maximising plant throughput.

Jan 1, 2009

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

Callie underground gold mine is part of the Newmont Tanami Operations, and is now the primary provider of ore to the Granites processing Mill. The Callie underground mine has produced in excess of 7.6 million tonnes (Mtpa) of ore, since production began in 1998, with a current production rate of 1.9 Mtpa. Callie underground uses sublevel open stoping with extraction through a combination of primary and secondary stopes. The primary stope filling strategy utilises cement aggregate fill (CAF) to allow full recovery of secondary stopes. The Callie backfill operation has had a continuous testing program in place during this time, which has resulted in a great deal of information available for post fill analysis. All CAF placement into primary stopes for Callie has been via surface boreholes and this has given Callie mine an understanding of some of the issues related to borehole design, type of linings to use depending on angle, depth and quantity of fill into stopes. Finally backfill barricades at Callie have undergone a number of changes during the time to optimise the design based on whether CAF or sand fill is used. This paper discusses the CAF backfill practices and testing methods used for backfilling operations at Callie.

Jan 1, 2005

By Prakash AJ, Singh PK, Dhar BB

Safety and stability of underground mine openings, coal pillars and water dams in the near vicinity of operating surface mines are endangered from excessive blast induced vibrations. This paper deals with the investigations carried out in four coal mines. Simultaneous measurements at equal distances from the source indicated higher level of vibration on the surface than those produced in the underground workings. The values of peak particle velocity (PPV) measured on coal pillars, body of water dam were lower than those measured on roof and junctions of the roadways. The parting of coal (3-4.5 m) between two sections vibrated with higher PPV compared to the roof of top section and floor of bottom section. In one case the influence of total charge fired in a round was significant in generation of vibration compared to the maximum charge/delay where monitoring was done vertically below the source.

Jan 1, 1995

By Smith C. B

Major diamond pipes discovered in Western Australia in the late-1970s exhibited a number of unique features that not only resulted in Australia becoming the largest diamond producer in the world in volume terms by 1986 but also changed geological thinking on the primary occurrence of diamond. They were: - lamproite is an alternative primary diamond host to kimberlite. - the extremely high mean grade of the Argyle lamproite pipe at 5 ct per tonne. - the tectonic setting of the lamproite pipes in mobile zones mar- ginal to the Kimberley Craton in contrast to the traditional African setting within stable cratons. Diamond was one of the earliest economic minerals discovered in Australia but 128 years elapsed between its first recognition and the first Australian economic pipe discovery (Argyle). During that period some 200,000 ct of alluvial diamonds were mined in Australia (mostly in New South Wales), but such alluvial output is insignificant on the world scene where annual production today runs at 95 million ct of natural stones some 76010 of which comes from primary pipe sources such as Argyle which alone produces 30 million ct per annum. Of particular significance therefore is the geological nature of the primary diamond source rocks in Australia. The Argyle and Ellendale Pipes are lamproites, differing from kimberlite in their mineralogy and geochemistry, and characterised by the presence of typical lamproite minerals such as leucite, priderite, potassic richterite, and the abnormally high content of chemical elements incompatible with ultramafic rocks. But not yet widely appreciated is that many other Australian olivine-rich lampro- phyres also contain diamond. Such picritic alkaline rocks can

Jan 1, 1988

By Brigden J. F, Birrell

A regional geochemical exploration programme commenced in July 1983, based upon low-density sampling of lateritic duricrust over parts of the Yilgarn Block of Western Australia. This resulted in recognition of an area significantly anomalous in chalcophile elements that progressively led to the discovery of the Johnston Range gold deposits in 1985. The deposits, on the Barlee 1:250,000 map sheet, occur in four mineralized zones, and production is expected to commence during 1988. The programme leading to the Johnston Range discoveries was a collaborative research/ applications study between the AGE Joint Venture (Greenbushes Ltd., St. Joe Minerals, and from 1985, Sons of Gwalia NL) and the CSIRO Laterite Geochemistry Research Group (Smith, 1987). It built upon a precursor project sponsored by Greenbushes Tin Ltd that commenced in 1980 and arose from an orientation laterite research project in the Greenbushes rare metal pegmatite district (Smith et at., 1987). Both were multi-commodity programmes and included the search for gold deposits. Basic methodologies for sampling and data interpretation have been described by Smith and Perdrix (1983) and Smith et at. (1984). Continuous geochemical coverage of designated parts of greenstone belts was sought using a triangular grid of 3-km or 1-km spacing, depending upon the expected prospectivity of the areas and the size and characteristics of the ore deposit targets. First-pass sampling, that resulted in the Johnston Range discoveries, was at 3-km spacing and several samples within a 30-km by 5-km area were

Jan 1, 1988

By J E. Wajon

This paper discusses the background, requirements, need and content of plans for management of drinking water self-supplied to mining-related operations, including construction camps, especially in remote areas of Western Australia. The paper discusses the importance of cooperation between regulators, the mine site operator and the consultant in preparing a plan fully compliant with the Australian Drinking Water Guidelines to protect the quality and safety of drinking water supplied to mine sites. The paper outlines some of the issues that need to be addressed in preparing a drinking water quality management plan, such as hazard identification, risk assessment, the multiple-barrier approach and the concept of critical control points. Data requirements, monitoring, incident management, training and reporting are also covered.CITATION:Wajon, J E, 2013. Drinking water quality management for mining operations in Western Australia, in Proceedings Water in Mining 2013 , pp 321-328 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

The sinking of the new No. 3 Shaft being mainly concerned with providing for the continuation of mining operations north of the existing workings, requirements for the shaft and haulage equipment were assessed, having in mind the anticipated needs of the Company in future years, the .available knowledge and probable future trends of the orebody, and also that the shaft would be required to act as a downcast airway for the ventilation system associated with the northern underground workings.

Jan 1, 1957

By Christie GB, Mainwaring DE, Leong YK

High solids brown coal slurries have been prepared with concentrations approaching those achieved with bituminous black coals. The high inherent water content and macroporosity of Victorian brown coals have been reduced in a controlled manner by chemical and mechanical means. The hydrophobicity of the coal surface has been increased sufficiently to reduce the tendency for swelling and water uptake. This together with densification has allowed the solids content to be progressively improved from 25% solids with raw coal to 65% solids with modified coals. Both raw brown coal and modified brown coal suspensions show shear thinning behaviour resulting in lower viscosities at higher flow rates. All coal suspensions displayed a yield stress once sufficient solids concentration was achieved. This yield stress can be used in the prevention of solids settling. Under simple shear mixing the network structure that provides the yield stress quickly breaks down to a low viscosity fluid with reduced yield stress and a pumpable consistency. The time necessary for structural recovery is in the order of days permitting shut-down and start-up of fuel delivery systems.

Jan 1, 1987