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By Rowley M, Bradford P

Plutonic Resources Limited (formerly known as Pioneer Mineral Exploration Limited) delineated, developed and operates the Plutonic Gold Mine located 180 kms northeast of Meekatharra, Western Australia. Gold mineralisation was discovered in the Marymia greenstone belt by Great Central Mines NL (GCM) in 1988. There was no previous, recorded gold mining activity in the area. In May 1989, Plutonic Resources Limited (PRL) entered into an agreement to acquire a 51 per cent interest in the three Mining Leases containing the Plutonic deposit from GCM. Subsequently in December 1989, PRL acquired the remaining 49 per cent interest in the Mining Leases. PRL and GCM are also involved in a 51:49 regional joint venture on extensive Exploration Licences in the vicinity of the Mining Leases. Following due diligence validation, reserve delineation and testwork, a feasibility study was undertaken in conjunction with JR Engineering Services, which led to the financing and development of the project for operation in August 1990.

Jan 1, 1991

By Brook W. H

The history of the reduction of iron from its ores is lost in antiquity. Archreologists state that man has practised it for over four thousand years. Until comparatively recent times charcoal was the principal reducing agent for making metallic iron from its various oxidised ores. Coke was first used by iron founders in England in 1619, and its use spread gradually throughout the civilised world from then onwards. Indeed, the destruction of forests to obtain the requisite charcoal made the iron founders, both in England and America, extremely unpopular, and this hampered the iron industry to a considerable extent, until coal provided the metallurgist with a new and better fuel--coke which is used by most pyro-metallurgists today. The transition from wood to coal products for iron smelting had a profound effect on the location of iron works. Particularly was this the case in America where, in the infancy of the industry, practically each of the early States had its own iron producers, but as coal and coke replaced charcoal, there came about a concentration of the iron and steel industry around the coking coal deposits, and so today there are huge steel plants clustered around the soft coal basins in Pennsylvania and Illinois.The development of the iron and steel industry in Australia, which is comparatively recent by world standards, has been cradled in the coal basins of New South Wales. The first steel works of any consequence in this country were built near Lithgow, close by the mines which produced the coal for coking.Incidentally, these works were rather unique in that the three essential materials for iron and steel manufacture-ore, coal, and limestone-were found virtually at the works' back door.When, in 1912, the location of the proposed steel works for The Broken Hill Pty. Co. Ltd. for smelting ore from Iron Knob in South Australia was considered, the site ultimately chosen was at Newcastle, almost on top of seams of satisfactory coking coal. One of the major factors which had determined the site of the steel works was the fact that, about 1912, three tons of coal were required to produce one ton of finished steel product, and the relative economics of ore and coal haulage were much in favour of bringing ore to the coal.

Jan 1, 1947

By Buisman C. J N, Koch R. O

Soil and groundwater beneath the Budelco zinc production plant at Budel-Dorplein (The Netherlands) are contaminated with metals and sulphate. To avoid contamination of nearby drinking water aquifers in the very distant future, a geohydrological containment system (GCS) and a microbial treatment plant for extracted contaminated groundwater have been developed. As a first step in the design of the system groundwater data from over 150 wells and geological profiles were used to model geohydrological conditions beneath the site. Several configurations of water-extraction wells were deduced from the model. Data gathered during additional fieldwork were then used to improve the model. Finally results that were calculated for the various configurations were used to select an optimal groundwater containment system. Currently some 5000 m3/day groundwater are extracted from a combination of 12 shallow and deep wells. Heavy metals and sulphate have to be removed from the extracted water before it can be discharged into the river system or used as process water. Several water treatment methods have been studied and pilot-tested at the site. The preferred and selected process is based on the activity of sulphate reducing bacteria (SRB) and combines sulphate removal and heavy metal removal in one single step. The anaerobic bacteria reduce the sulphate to sulphide resulting in the precipitation of metal sulphides. A pilot plant gave promising results and a commercial-scale plant has been designed. The proposed design has been tested in a demonstration plant which included all main process units. Test results for all process units are presented. The collected information was then used to optimise the design of the commercial-scale plant. Special attention was paid to automation and safety items. Construction of the plant was finished in May 1992. Start-up, commissioning and operational experience are reported. The concentrations of metals and sulphate in the effluent of the SRB water treatment plant are well within the limits set by the authorities for discharge to public waters.

Jan 1, 1993

The mechanism of caving is of interest to the mining engineer only in areas where he is directly concerned. One area is surface subsidence which is outside the scope of this paper. Another area is at the face where coal is being extracted and where control of caving is of vital importance. Coal mining systems have been developed with many considerations in mind, but in this list of considerations, strata control has seldom been given much importance. Research is in progress in Australia to endeavour to determine an optimum sequence for coal extraction underground. As information becomes avail- able from this work it is hoped that appropriate methods of controlling caving in various strata conditions will be devised. When this is done, equipment may be introduced to permit the mining operation to proceed under optimum conditions for strata control, rather than devising a mining procedure to suit the equipment available and methods developed for other reasons.

Jan 1, 1974

Results from current NERDDC funded research into the geotechnology of highwall trench mining methods have clear implications for mine planners in the areas of blast design, trench shape, location of the surcharge spoil and remnant coal pillar design.Adoption of successful smooth wall blasting techniques not only removes safety hazards from the trench face, but limits development of bedding partings at the seam contacts that interrupt the smooth transition of stress across the coal seam.

Jan 1, 1992

By Carter A. C

The increasing need for alternative energy sources as well as the less clearly perceived but equally increasing demand for non-fuel minerals has resulted in extensive exploitation of near surface deposits. Many such deposits have depleted reserves and mining corporations are increasingly turning their attention to deposits, with thicker overburden, less competent materials, steeper dips and more complex structure. These deposits pose mine layout, geotechnical and equipment problems as well as the need for large outputs to achieve economies of scale. The paper describes the major problems and operational solutions for such deposits using continuous excavation and transport equipment.

Jan 1, 1980

The copper deposits at Pernatty Lagoon are predominately djurleite-digenite bodies beneath the permanent water table, and chrysocolla-atacamite-malachite above the permanent water table. The minerals havebeen deposited as sheets, lobes, and pods in zones suggestive of permeability channels or permeability basius with respect to groundwater circulation.Pyrite is deposited in the form of framboids, which reflects its biogenic origin. Copper-iron sulphides deposit by replacement of pre-existent pyrite, and rarely by direct deposition. The latter mode of formation results in complex crustification bandings of chalcopyrite, bornite, sulphur rich bornites, digenite, and blue remaining covellites. The copper-iron sulphides appear to reequilibrate under constrained oxidation, resulting in an iron depletion and associated copper enrichment, the final product of which is a djurleite-digenite assemblage and associated with goethite. Where copper mineralization/ host rock relationships have rendered the rocks entirely impermeable to post ore groundwater movement, then the copper-iron sulphides are preserved as the ore assemblages.Minor and trace minerals observed include sphalerite, carrollite, galena, wittichenite, and possibly tetrahedrite in the primary ores. In the oxidized ores cllprite, tenorite, and trace brochantite have been found.

Jan 1, 1976

This paper is based on studies made intermittently from 1937 to 1950. Its object is to describe the surface geology and the tin lodes, and to relate the lodes to the structure of the field.PREVIOUS REFERENCESR L. Jack made his first report on the field in 1880, but his principal report was made in 1883. W. E. Cameron described the Great Northern lodes in 1904. Numerous later reports on various mines were made by L. C. Ball, J. H. Reid and C. C. Morton, the most important of which were on the Black King, Good Friday, St. Patrick and the Great Northern Gully Shaft.GENERAL GEOLOGYJensen maps the Herberton area as part of a granite massif intruding rocks of two ages, the Younger Metamorphics of Silurian-Devonian age, and the Older Metamorphics of Older Palaeozoic age. The distinction is apparently based on lithological data. The Older Metamorphic rocks occur as inliers in the granite massif to the west and east of Herberton (Fig. 1).The area described consists of granite traversed by numerous dykes. West of the area, approaching the Older Metamorphic rocks, the granite becomes finer grained as if chilled towards its contact, and the dykes more numerous. To the east, passing from the Nova Scotia mine to Mount Lavery there are numerous dyke rocks, but the outcrops are poor and knowledge of the geology indefinite. The area is the main tin-producing area. To the west there are comparatively small tin lodes in the granite, and the "Copper Firing Line" occurs in the Older Metamorphic...

Jan 1, 1951

By Schoning W. L

Ore deposit models form the basis for numerous other economic decisions in the mining process. The success of these economic decisions therefore depend directly on the accuracy of the ore evaluation process. The Geology Department at the Sishen Iron Ore Mine is responsible for the generation of a reliable geological computer model of the rock material with predicted grades. This information is then utilised for further ore reserve calculations, mine planning, production scheduling and grade control. Owing to a very complex geological orebody, grades and beneficiation characteristics differ significantly from sample to sample. This means that ore evaluation is a difficult process and great reliance is placed on computer techniques. In 1993, preparation for the ISO 9002 quality certification of the mine motivated the Geology Department to hold formal `problem solving' sessions in order to identify and revise problem areas in operating

Jan 1, 1995

By Rose CW

Typical rehabilitation programmes for spoil piles and waste dumps in open cut coal mines involve the spreading of topsoil to assist vegetation growth. In the early years of rehabilitation before a protective vegetation cover has been established, this topsoil is susceptible to erosion during rainfall events. Since the long term success of rehabil- itation procedures is sensitive to adequate topsoil maintenance and since, on many mine sites, topsoil is a scarce resource, erosion losses of topsoil (particularly once fert- ilised) can severely restrict rehabilitation Measures.

Jan 1, 1983

By Mann T

The use of dolomite as a refractory began in England about 1870 when the basic Bessemer process for the removal of phosphorus from steel was developed by Thomas and Gilchrist.Knowledge of dolomite as a refractory in this country goes back to the early part of this century, at the time when the Hoskins Brothers took over the Lithgow Iron and Steel Works from W. Sandford. The practice then was toimport burned dolomite in casks from England. It is reported that much of the material was powdered when received, but was still serviceable. The earliest. used sources of local stone were in the Bathurst and Mudgee areas of New South Wales, and these dolomites were first used raw. Later, dolomite was burned in cupolas at Havilah near Mudgee, coke being obtained from the South Coast of New South Wales. This plant supplied burned dolomite to the Lithgow steel plant, later to the Australil1n Iron and Steel plant at Port Kembla, and also to the electric steel furnaces at Newcastle, Sydney and Melbourne until the plant was closed down in 1946.The Broken Hill Proprietary Company first obtained its dolomite from George's Plains near Bathurst (this was, really a magnesium limestone) and later from Mount Knowles, a deposit near Mudgee, which was eventually taken over by the CO:plpany in 1918. In 1936 Australian.Iron and Steel acquired from the Southern Portland Cement Company a deposit at Mount Fairy in the Federal...

Jan 1, 1951

By Player R. L

Measurements of the rate of PbO reduction from high lead metallurgical slags were made under laboratory conditions using graphite, a CO-50%CO2 gas mixture and metallic iron as reductants. The results show a transition in rate-controlling step at low PbO contents (i.e. 6 wt.% PbO). At medium to high PbO contents in the slag, the reduction rate was found to be strongly affected by the slag chemistry, temperature and reductant type. The effect of stirring and hence mass transfer in the slag phase on the reduction rate of PbO was found to be insignificant at medium-high PbO contents. Attention is drawn to the importance of chemically controlled reaction rates at the slag-gas interface. Parallels between these results and test work on a 5 tph scale have been briefly drawn.

Jan 1, 1989

By Cutafani M, Lama R

An approach to combatting abnormal roof control conditions in underground coal mines is outlined. Support techniques available are discussed along with the methods available to be adopted in different situations. Properties of materials available presently are tabulated together with the conditions of their Application.

Jan 1, 1988

By Vnenk L, Hargraves AJ

Metropolitan Colliery has some areas of roof where immedi- ate support is required in development. The disadvantages of percussive roof bolting at the face have led to recent produc- tion trials with rotary boring and rapid=setting resin anchored roof bolts developed at the Colliery. The three innovations involved are: (1) the wet drilling of small holes with an all- hydraulic, portable rotary boring machine; (2) the rapidity of loading a "point anchored" resin bolt; and (3) the consistently high anchorage strength available. All three innovations provide striking advantages over the previously available alternatives. The greatest disad- vantage - that of cost of resin - is not prohibitive, and there is promise of improvement in the future. There are possibilities of variations of the techniques for special support problems in particularly difficult roofs.

Jan 1, 1971

By G A. Partington

Recent research has highlighted the potential of a relatively new style of gold mineralisation related to granite intrusion. New discoveries in Alaska, Central Europe and Asia and Eastern Australia with total resources of 1600 t Au offer attractive targets for regional exploration in areas which may have been overlooked in the past. A spatial information system was developed to target granite-gold systems in eastern Australia and the West coast of New Zealand, using well constrained geological and exploration models derived from current research. Target areas were recognised in Queensland, New South Wales, Victoria, Tasmania and on the West Coast of the South Island of New Zealand that have similar spatial data relationships to known granite gold mineralisation elsewhere in the world. The second phase of the modelling better constrained the regional scale target areas by including more detailed geological, geochemical and geophysical data in the GIS to develop prospect-scale targets and to allow the acquisition of tenements over these areas. A geological review of each target area was carried out in the field to put the GIS models into context. The fieldwork has highlighted the potential for this style of mineralisation in New Zealand and will increase investment in mineral exploration and development in New Zealand in the near future.

Jan 1, 2005

By Gordon A. R

The effect of various types of solid carbonaceOlls reductants on the rate of fuming of zinc from lead blast furnace slag was investigated at I250°C.The results of the laboratory experiments indicated that the rate of removal of zinc from slag depended primarily on the volatile matter contents of the reduclants. The effects of fixed carbon, moisture and ash contents were less significant.

Jan 1, 1992

The evolution of the Oaky Creek mining complex provides a good example of the mining cycle in practice. Oaky Creek has been innovative in its choice of mining methods, with virtually the full range of coal mining methods having been used as workings have progressed down dip. The history of the mine is traced through its development (and ownership changes), progressive selection of mining methods as depths of cover to seams being mined have increased, and rehabilitation. This allows the different mining methods to be described and illustrates the concept of æwall-to-wall miningÆ.

Jan 1, 1998

The Wellington Dam catchment has high value water, agriculture and coal and power generating resources. These conflicting land uses are managed through consultation and regulation. The Wellington Dam catchment is unique in that the Collie Coal Basin is located almost to the edge of the dam and has coal mining and power generation as its primary land use. Currently the dam is only used for irrigation due to its high salinity. The State Government has committed to reduce the damÆs salt levels to below 600 mg/L by 2015 so that it can be considered for public drinking water supply. The coal industry in conjunction with the community and State Government has worked together to enhance the water quality within the Wellington Dam to maximise its value and use by using mine dewater for industry, diverting saline Collie River flows, providing environmental (social) flows and enhancing water quality of mine voids to encourage new industry to the Collie Region. Both surface and groundwater in the coal basin are generally fresh, whereas the salinity in the Collie River East Branch generally ranges between 3000 to 20 000 mg/L and 1700 to 10 000 mg/L in the South Branch. Mine dewatering is currently two to three times greater than the recharge to the coal basin. As a result, all mine dewater is sent to power stations in the area, with excess discharged into drainage lines which flow into the South Branch of the Collie River. To maintain environmental and social flows some groundwater is also pumped to the South and East Branches of the Collie River during summer months. Completed mine voids are used for recreation and options for aquaculture are promising. However, handback criteria are yet to be finalised.

Jan 1, 2006

Many of the large refrigeration plants used in, the cooling systems on deep South African gold mines are situated on surface where they are exposed to seasonally and diurnally varying climatic conditions, and to a diurnally varying demand for cooling made by the mine. It has been traditional to accommodate the seasonal variation in climate by manual control applied to the plants at appropriate times of the year, and the plants have normally been specified to conform passively to the diurnal variations. This paper introduces new strategies for the active automatic control of the plants on a diurnal cycle, and shows that attractive benefits in energy and chilled water resource management can be accrued through the use of these strategies. The results have been derived through the modelling and simulation of a representative refrigeration plant.

Jan 1, 1985

By Kajioka H, Nakamura Y

Na2CO3 is a powerful flux for both dephosphorization and desulphurization in oxidizing atmospheres. In order to study refining with Na2CO3 and the nature of the Na2CO3 slag itself, hot metal (4Kg) was melted in Al203 crucibles in a high frequency induction furnace and oxidised with oxygen under Na2CO3 slag. The behaviour of Na2CO3 at high temperature was observed by thermobalance. It was found that dephosphorization ceases in a few minutes and [,P] after refining is easily lowered to less than 0.010%. [%P] after refining is affected by [Si], [P] of hot metal, the refining temperature and the consumption of Na2CO3. Desulphurization also ceases in a few minutes but it shows curious behaviour, increase of [S], decrease of (S) and increase in sulphur lost, during the latter half of run. [%S] after refining is also affected by [P] of hot metal, the refining temperature and the consumption of Na2C03o

Jan 1, 1980