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This paper discusses basic practices of operation applied to raise drilling. It draws attention to critical areas that tend to be neglected. A brief history covers development of raise drills. The elements of the equipment, derrick assembly, drill string and reamers are ex- amined. Particular emphasis is on the drill string. It is concluded that manufacturer and operator can benefit each other by closer interchange of ideas.

Jan 1, 1977

The limitations of the conventional practices, and their effects, in prospecting for and in the evaluation of alluvial gold deposits are briefly reviewed. Geophysical prospecting methods have demonstrated their complementary role in the delineation of deposits by reducing the number of boreholes which are primarily of a 'probing' type. Larger diameter boreholes, although more expensive on a linear basis, are much cheaper on a volume recovered basis. The need to have sufficient volume as well as number of samples is stressed. Classical statistical methods are not appropriate for such deposits as there is sufficient structure, or spatial correlation, to require the application of geostatistics. Quite reliable semi-variograms, but not in all cases, of the spherical scheme have been obtained. Subsequent kriging has, to date, been confined to unworked deposits: retrospective estimates to compare to production have not therefore been produced. However, the technique shows promise but indicates a considerably greater borehole density (of the conventional diameter) may be necessary to produce confident estimates. Used in conjunction with larger diameter boreholes, a lesser borehole density may be sufficient, through radical reductions of the sampling error.

Jan 1, 1977

By Hengst B

The first production stage in any mining operation is the breaking of whole rock into fragments small enough for loading and subseq- uent handling. This primary fragmentation is most frequently accomplished with blasting. The maximum fragment size and the fragment size distribution have an influence on the subsequent loading, handling and crushing costs. It is assumed that total rock fragmen- tation in practice is a result of an interact- ing array of radial cracks from various blastholes. The representation for the basic pattern of radial cracks emitted from a particular blasthole is first described. A model is then developed simulating the interaction between blastholes at various burdens and spacings, and in simultaneous and delayed modes. The resultant picture is analysed and a fragment size distribution calculated. Methods of incorporating the existing faults in the rock are also discussed. Finally application of this model to various facets of mining are considered.

Jan 1, 1977

By Fairhurst RM

High pressure abrasive water jets have been shown capable of cutting a wide range of materials including steel, stone, rock and concrete. Acceptable performance can be achieved using relatively low pressures and expendable abrasives. The cutting head can be made small and abrasive feed systems have been developed that allow reliable pumping of slurries over long distances to supply such cutting heads. These features make abrasive water jets ideally suited to automated control in remote areas.Another major advantage of abrasive entraining water jet cutting heads is that they may be operated safely in potentially explosive environments due to their cold cutting ability. Therefore there are many possible applications for such equipment in mining.This paper gives an introduction to the abrasive water jet process and includes results of trials carried out at BHRA on a range of hard materials. Work is also described which investigated the operational safety of abrasive water jets in explosive environ-ments. In a special environmental chamber, cuts were made on steel and sandstone with atmospheres of methane/air and hydrogen/air, without caypsing ignition.

Jan 1, 1985

The accuracy of an ore reserve is only as good as the geologist's understanding of the deposit. The methods that are applied to resource and reserve estimation reflect that understanding. At the Olympic Dam copper-uranium-gold deposit in South Australia, evolution in the understanding of the controls on mineralisation coupled with the changing demands of the project have led to changes in the approach to reserve estimation. The project has moved into a phase where detailed stope mining reserves are now required as distinct from global ore reserves. The complex nature of the mineralisation and the large amount of data demand that all available information be readily accessible in a flexible format. To enable the selective manipulation of geological and assay information and its characterisation, a relational database has been developed. For reserve calculations themselves, initial computations were based on a system derived from that used for the Kambalda nickel orebodies. The Olympic Dam system differed mainly in the use of statistical analyses in the estimation of grade instead of the previous polygonal area of influence weighting method, Three dimensional weighting techniques are now being used for local reserve estimates. Flexible facilities for raw data handling combined with grade estimation techniques which are commensurate with the mine geologist's understanding, produce detailed gridded and contoured ore zone models suitable for reserve calculations and stope designs.

Jan 1, 1987

The Olympic Dam Project constitutes a major resource of Copper and Uranium and has been under intensive evaluation since the discovery in 1975.A 500 metre deep rectangular shaft has been sunk into the deposit and this has been followed by 8400 metres of level, incline and decline development. 5 surface ventilation raises have also been constructed.Large scale trackless equipment is used to carry out the development, and productivity statistics are given.The paper describes the functionalised system used in the development program and discusses the maintenance support, and services required to carry out these works.The objectives of the Exploration Development program and the satisfactory results obtained from this work are also discussed.

Jan 1, 1985

By Gelding P. W, van Herk H

The Cattlegrid copper orebody is a concealed thin, tabular sheet localised near an unconformity between two sub- horizontal Precambrian sandstone units. It extends over an area of 1,000 m by 500 m within a wider area of mineral- isation. The ore consists of complex sulphides and is neither massive nor disseminated. It consists mainly of irregular fillings in pore space developed between clasts in sandstone breccias, in fault zones and joints and along stratification planes. Its habit is unique amongst Australian base metal ore bodies. During the pre-development period ore was outlined by percussion holes but in studies leading to investment decisions ore reserves were manually calculated from intercepts and assay results of cores from diamond drill holes. The methods used for estimating reserves in the pre-production and production periods are described and evaluated by comparing mine production during the first five ore production years with the forecasts made.

Jan 1, 1979

By Gallet M, Watsford R. M S

The 1989 feasibility study of the chessy, france, copper, zinc, pyrite and barite orebody was based upon a classical flowsheet. The flowsheet included, three stages of crushing, conventional rod and ball mill grinding in series, and sequential flotation of four products utilising conventional mechanical flotation cells. To improve the profitability of the project the partners commenced a search for ways to reduce the projected capital and operating costs of the proposed development. This paper presents the improvements in the projected capital and operating costs as a result of design and concept changes. The major changes included: ò the simplification of the crushing section with the adoption of semi autogenous grinding (SAG) milling of primary crushed ore. ò the deferral of pyrite and barite flotation circuits until market conditions were positive. ò the simplification of the flotation circuit by the use of column flotation cells for combined rougher/cleaner duty. ò the purchase of second hand equipment. The result of these changes was to reduce the capital cost estimate of the plant from US$ 21 million to US$ 11 million and operating cost estimates from US$ 18.90 to US$ 13.60 per tonne of ore for a decrease of approximately ten per cent in potential revenues.

Jan 1, 1991

The fast rate of development in the micro technology industry is enabling computer based systems to be used in ways never considered before. Micro technology can be used to great advantage in the mining industry to improve both safety and productivity. The planned use of electronic 'IN/OUT' boards at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) mines will provide a much improved system for checking that the mines are clear before firing. The provision of remote ocaputerised core logging facilities made possible by small remote data entry terminals will greatly improve the productivity of the personnel involved in all stages of core Logging.

Jan 1, 1983

By C M. Hill

This paper aims to provide a brief overview of the Australian Coal Bed Methane (CBM) industry and more importantly the challenges to sustainable management of the industryÆs by-product, groundwater. In a country where water is scarce and having gone through one of the worst recorded droughts it is vital that this important industry be seen to be managing water in a responsible manner with the greatest environmental and social benefit. Benefits of the water from CBM wells can be enhanced through treatment to produce potable water for domestic or stock purposes, water for irrigation or aquaculture or lower quality or untreated water for industrial or mining purposes. Other options are re-injection of raw water or waste from the treatment processes or discharge to surface waterways. The critical change and difference between CBM projects and traditional oil and gas operations should be that where possible water is no longer disposed of via evaporation ponds with the dual legacy of waste of the water resource and an environmental contamination problem with the remaining salt and brine product.

Jan 1, 2003

By Weir D. R, Doyle B. N

The Sherritt Zinc Pressure Leaching Process is based upon the direct pressure leaching of zinc sulphide or lead-zinc bulk sulphide concentrates to produce zinc sulphate in solution and elemental sulphur in the leach residues. The zinc sulphate solution is compatible with conventional purification and electrowinning technology. The pressure leach residues can be treated for the recovery of elemental sulphur, lead and silver. With the conversion of sulphur to the elemental form, zinc pressure leaching allows zinc winning to be independent of sulphuric acid production. Direct pressure leaching of zinc sulphide concentrates was started commercially in October 1980. Continuing research and development studies have defined various pressure leaching configurations for integration with existing roast-leach operations, for grass roots plants, or for plants which are to have the roast-leach section completely replaced. These studies have included the treatment of zinc concentrates from various Australian producers and the development of process flowsheets for potential applications in Australia.

Jan 1, 1989

By Granholm S

The current emphasis within the mining industry to reduce the cost of production has stimulated interest in the fields of maintenance and operational reliability of capital intensive mining equipment. From an economic point of view, high reliability is desirable to reduce the maintenance costs of the systems. Two graphical methods consider reliability analysis. The first one, the method of Total Time on Test (177)-plotting deals with the reliability data which are free from trend and serial correlation. The second method which is based on time dependent modelling approach deals with the data which are not free from trends and serial correlation. The examples show how these graphical methods can be used to calculate the optimal maintenance intervals for components or systems.

Jan 1, 1991

By Stewart Gillies AD

Resource rent taxes are taxes which only become effective at such a time as a pre-determined rate of return has been achieved by an operation. Resource Rent Taxes have from time to time been considered for implementation in both Australia and New Zealand. The offshore petroleum industry in Australia is already subject to RRT as is the Roxby Downs (Olympic Dam) Mine in South Australia. Both the mining and petroleum taxation regimes in Papua New Guinea include a resource rent tax component called Additional Profits Tax.

Jan 1, 1995

By Kidd CH

The excavation of a coal mine or any other mine, tunnel, or quarry, below the water table establishes a void towards which ground- water will flow. Inflows into the mine, if significant, can cause not only problems such as flooding, and/or muddy floors, in the mine, but commonly also require disposal of poor quality groundwater. The flow of groundwater towards a mine is accompanied by a decline in groundwater levels, which may extend up to several kilo- metres around the mine. This may seriously effect vegetation, stream flow and existing users of groundwater. At the pit face groundwater gradients can also cause slope stability problems and where a water table is intersected, increase blasting costs.

Jan 1, 1983

Modelling of Magnetic Carrier Separation Process Using Computational Fluid Dynamics

Sep 13, 2010

By M Balamurali

In mining, grade control generally focuses on blasthole sampling and the estimation of ore control block models with little or no attention given to how the materials are being excavated from the ground. In the process of loading trucks, the underlying variability of the individual bucket load will determine the variability of truck payload. Hence, accurate material movement demands a good knowledge of the excavation process and the buckets’ interaction with the environment. However, equipment frequently goes into off-nominal states due to unexpected delays, disturbances or faults. The large amount of such disturbances causes information loss that reduces the statistical power and biases estimates, leading to increased uncertainty in the production. A reliable method that inferences the missing knowledge about the interaction between the machine and the environment from the available data sources, is vital to accurately model the material movement. In this study, a twostep method was implemented that performed unsupervised clustering and then predicted the missing information. The first method is Density-based spatial clustering of applications with noise (DBSCAN) based spatial clustering which divides the diggers’ and buckets’ positional data into connected loading segments. Clear patterns of segmented bucket dig positions were observed. The second model utilised Gaussian process regression which was trained with the clustered data and the model was then used to infer the mean locations of the test clusters. Bucket dig locations were then simulated at the inferred mean locations for different durations and compared against the known bucket dig locations. This method was tested at an open pit mine in the Pilbara region of Western Australia. The experimental results demonstrate the advantage of the proposed method in inferencing the missing information of bucket-environment interactions and therefore enables miners to continuously track the material movement.

Jun 22, 2022

An outline of the circumstances giving rise to the current Commonwealth-States con- flict in relation to offshore mineral explor- ation and production is set out, together with an analysis of the Seas and Submerged Lands Act 1973. The bases of the claims by the Commonwealth and the States in this regard are discussed with relation to the territorial sea and the continental shelf.

Jan 1, 1974

By Loughnan FC

There are some thirteen laboratories in Australia in which coal petrological work is carried out on a consistent and routine basis. Applied coal petrological research is conducted by several institutions in different disciplines which can be grouped into four main categories:

Jan 1, 1989

By H Kundapen, B Bolton, S Miller

The Ok Tedi porphyry copper and gold mine is an open-pit operation located within the Star Mountains in the Western Province of Papua New Guinea and is situated near the headwaters of the Ok Tedi-Fly River system. The climate is equatorial sub-alpine with rainfall ranging from five to ten metres per year. Mining commenced in 1984 and to-date approximately 500 Mt of waste rock has been produced. A failing waste rock dump system operates whereby the dumps are eroded by tributary creeks of the Ok Tedi. It is estimated that approximately 250 Mt of waste is retained within the upper reaches of the river system. The waste rock comprises both potentially acid forming rock and limestone and to-date the overall waste has been acid consuming. However, the long-term mine plan identifies declining limestone production and hence an increasing risk of acid generation over the remaining years of the operation. A program was initiated to determine the net acid producing potential (NAPP) required (ie target NAPP) to minimise the risk of acid generation within the waste rock dumps. The results from this program provide guidelines for an operational target NAPP strategy to provide sufficient acid buffering across all size fractions in the waste rock dump for long-term ARD control. Implementation of this plan requires additional limestone to be mined and co-disposed with ROM waste rock.

Jan 1, 2003

A major tool in the search for petroleum is reflection seismic mapping. The period which has seen most of the exploration in Victoria is also one which has seen major advances in this technology, from 1963 try present day. Seismic mapping can be divided into three interlinked areas - acquisition, processing, and interpretation. In acquisition the major changes have been from an explosive energy source in 1963 to gas exploders in 1968 and airguns in 1970. The number of recording channels has increased from 24 to 192, with digital recording introduced in 1966, and floating point recording in 1976.

Jan 1, 1982