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Because of the coincidental location of orebodies and population in Australia, the mineral sands industry has been subjected to numerous land use conflicts, resulting in the sterilisation of strategic ore reserves and a severe downturn of activity in the eastern states. All tiers of government of various political persuasions were responsible for the decisions leading to this sterilisation. As such, it became a community response to intense land use pressure along an attractive and popular coastline. The resultant high public exposure of the industry has placed it in the forefront of developments in rehabilitation technology. In eastern Australia, the industry has operated in a wide range of ecosystems, many with conservation values. Rehabilitation ech- niques have been developed to suit these varied conditions, and much of this technology is now widely adopted throughout the mining industry. Land use considerations in Western Australia are somewhat different to those of the eastern states. Nevertheless, the same basic principles of rehabilitation apply with modification to suit local conditions and land use objectives. The development of rehabilitation in both Eastern and Western Australia is reviewed, and the direction of future trends is indicated.

Jan 1, 1986

The only functional underground Coal Mine in Nigeria is located in Enugu in Anambra State. For some years now the mine has been beset with a perenial problem of flooding. This has hampered produc- tion and some time ago the mine was abandoned. Recently money and equipment were made available to reactivate the mine. Attempts are now made to increase production as it is very much below demand. However, there are problems as the mine is below the water table under some major rivers and any advance exposes men and equipment to water surge. The paper traces the different attempts made to dewater the mine and the problems encountered in producing coal in this mine.

Jan 1, 1988

By Dorricott M. G

Ballarat Goldfields NL is developing an exploration decline at Ballarat East using a Mitsui Miike S-125 roadheader. To-date, 530 in of advance has been achieved at an average rate of 16.1 m/week. Roadheader availability has averaged 94.3 per cent, and pick consumption has averaged 0.016 per m. Ground support has involved pattern rockbolting with split sets, 100 mm thick fibre reinforced shotcrete, and steel sets as required. The slower than expected advance rate has mainly been due to difficult ground conditions. It is expected that a further 970 in of decline will be mechanically excavated before a drill and blast system becomes more economical.

Jan 1, 1995

From August 1962 to June 1976 Peko Mines Ltd. produced Gold Bullion at the Peko Control Mill using 18x24 Denver Mineral Jigs and strake tables. Gold ores treated during this period were obtained from Orlando, Juno and Ivanhoe Mines and from the Warrego Mine after 1974, all in the Tennant Creek Area of the Northern Territory. With the downturn in copper prices Warrego Copper ore mining ceased and the copper Smelter closed down in February 1974, Warrego gold ore continued to be treated in the Peko Concentrator.

Jan 1, 1978

By Newell RB

Grinding circuits are used in most mineral processing plants. Their widespread application makes the efficient running of the circuits essential to almost all resource projects. This paper will show that, with the application of modern multivariable control techniques, improved plant performance can be obtained when compared with conventional single loop control strategies. Results are presented for a simulated closed-circuit ball mill.The grinding circuit was controlled using the rod-mill water and primary and secondary sump dilution flowrates as the manipulated variables. Variables controlled were the primary cyclone feed flowrate, the primary cyclone feed density and the particle-size measurement (percentage smaller than 75 um).

Jan 1, 1985

A new watersoluble binder for mineral ore pellets has been developed by the sulfonation of bituminous materials. A highly effective binder for iron ore pellet making is obtainable from bituminous materials produced in the hightemperature cracking of crude oils. This paper deals with production process and basic properties of this binder as well as new applications in the field of iron ore pelletizing.

Jan 1, 1974

By Fraser RJ

A Robbins Raise Drill Model 61R was used to provide one 7' diameter shaft 1050' deep in Clutha Development's exploratory mine at Blackwater in Central Queensland and two 7' diameter shafts 1450' deep at their South Clifton mine on the Illawarra Coast of New South Wales.

Jan 1, 1972

Cobar Mines Pty. Limited (CMPL) uses sodium sulphite as the principal depressant to attain selectivity in copper flotation prior to sequential recovery of lead and zinc. The usage of sodium sulphite is examined both from a theorectical viewpoint ana from the manner in which the copper circuit at (MPL has developed. The results of relatively recent investigations, both in the laboratory ana the plant, are discussed aria shown to support the present operating Techniques.

Jan 1, 1983

The Big Bend and Cobra molybdenum prospects which occur near the margin of the Karamea Batholith in the Northwest Nelson molybdenum province are compared. The Big Bend Prospect is a 3000 m by 800 m area of disseminated pyrite and anomalous molybdenum associated with Cretaceous porphyry intrusives and later argillic and potassic alteration within Ordovician schists and phyllites adjacent to the batholith margin. The Cobra Prospect is a 1200 m by 1200 m area of weakly disseminated pyrite mineralisation and anomalous molybdenum-in-rock associated with moderate to strong quartz-molybdenite and quartz-orthoclase-molybdenite veining in quartzite.

Jan 1, 1979

As the oxide reserves in an oxide/sulphide deposit are exhausted transition to the treatment of sulphides should be investigated in detail and well before processing the sulphide ore commences. The investigation should be broad based to consider all treatment options and not restricted entirely by the existing process plant treatment method. These options may include cyanidation, flotation, roasting, bacterial leaching or gravity treatment and are chosen on the basis of various testwork responses. Experiences in laboratory testing of sulphides and treatment of sulphides at various operations are discussed. This includes the treatment of copper/gold sulphides, CIP treatment of sulphides and treatment of marcasite ore in a conventional CIP circuit.

Jan 1, 1989

By P Trotta

The majority of water to the Olympic Dam mine and the nearby townships of Roxby Downs and Andamooka is supplied from the Great Artesian Basin (GAB). There are no permanent local water sources available to Olympic Dam. The use of water from the Great Artesian Basin by Olympic Dam receives considerable attention by BHP Billiton and is extensively regulated by the Government of South Australia. Olympic Dam has robust business management systems in place to ensure the sustainable use of water from the GAB including ISO9001 and ISO14001 systems to deliver the targeted outcomes and obligations of the Olympic Dam Environmental Management and Monitoring Program. The management systems ensure that Olympic Dam retains accountability for its water demand from the GAB over the life of the mine. This accountability has delivered continuous improvement in water use efficiency driven by operating discipline, implementation of water saving projects, using water on a fit for purpose basis including substitution from non-GAB sources, and risk management to prevent and mitigate water supply disruptions to Olympic Dam and Roxby Downs. Since the establishment of Olympic Dam, BHP Billiton has funded a reduction in GAB water flow from bores, previously going to waste, that is greater than the annual average flow used by Olympic Dam.

Jan 1, 2009

Fluid circulation occurs in oceanic crust of all ages, at the seafloor spreading axis, on mid-ocean ridge flanks, in the ocean basins, and in subduction zones. In the first three settings the fluid originates as seawater. At the axis and on the ridge flanks, the circulating seawater produces a major chemical exchange between the oceans and the crust. Based on heat budget constraints, between 10 and 40% of the river flux of Mg can be taken up during high-temperature alteration of the basaltic crust along the mid-ocean ridge axis. Most of the hydrothermal -heat loss, however, occurs on the mid-ocean ridge flanks, where the temperatures are lower and the seawater flux correspondingly larger. The estimated heat loss on the flanks is so large that upwelling must occur over a large fraction (5-30%) of the seafloor less than 65 Ma in age, at seepage velocities on the order of 10 to 100 cm/yr. The circulating seawater need lose less than 1 to 2% of its Mg content in order to solve the Mg mass balance for the oceans. Fluids in subduction zones are commonly less saline than seawater and are rich in methane and other light hydrocarbons. These fluids may originate by dewatering of the downgoing slab. If so, they may close the geochemical cycle of H2O that began with hydration of the basaltic crust at the ridge axis.

Jan 1, 1990

By Just GD, Gillies ADS

The competitive coal market has required coal producers to put more effort into coal quality control. Successful quality control requires a good estimation of the in situ coal quality as well as a good estimation of the probable fluctuation of the in situ coal quality during production. Geostatistics offers a very promising way to meet this requirement. A geostatistical approach toward the coal quality control problem is presented. Two models, the prediction model and the conditional simulation model, have been developed for coal quality data from two large export coal mines in central Queensland, Australia. The mine planning and scheduling aspects based on this and other potential applications of the models are addressed.

Jan 1, 1990

By Seedsman R. W

Good roads are essential in moving men and materials to and from the underground workplace. Coffey Partners International Pty Ltd (Coffey) has recently completed a underground coal industry funded project on underground mine road construction and maintenance. This paper discusses practical approaches to construction and maintenance of underground mine roads using transferrable civil technologies and innovative techniques. Mine pavements are generally low-cost (relative to civil roads), constructed to varying standards using locally available materials to best meet the mobility needs of the mine. Performance of pavements is thus largely dependent on the environmental conditions, quality of the available road making materials, maintenance policies and available resources. The paper will detail `what causes bad roads?' in various underground environments, available management strategies, construction and water control techniques, road maintenance and vehicle considerations.

Jan 1, 1995

By A Purvee, M F. Lee, L J. Mollison

Oyu Tolgoi is a large Cu-Au porphyry deposit in the south Gobi desert, Mongolia. The first of several deep, large-diameter, concrete-lined shafts, Shaft 1, is nearing completion. It will have a finished depth of 1380 m at a diameter of 6.7 m. These shafts will provide access to and hoisting capacity for block caving of deep underground ore. Geotechnical site investigations, and associated predictions of stability and ground support requirements, are compared against actual construction performance. Routine mapping is essential, along with checks against predictions and informing the contractor of ground conditions and variances.Advance rates are compared against predicted rock mass quality. A reasonable correlation exists between Qwall and advance rate. Overbreak and concrete liner thickness is related to the blockiness quotient, RQD/Jn.A ætool-bagÆ of just a few support elements (chain-link mesh, fibrecrete and 2.4 m long friction anchors and resin grouted re-bar bolts) was able to cope with the ground conditions encountered. QA/QC procedures are essential from the factory, through site storage to installation.

Jan 1, 2008

By Ralph AM, Deakin JJ

A quantitative knowledge of underground mine ventilation requirements and conditions has become increasingly important, both to meet statutory requirements and to ensure high levels of safety and productivity within mines. The ACIRL Mine Ventilation System MINVENT was designed to provide a flexible means of analysing the behaviour of an underground mine ventilation system under a variety of conditions. It is not sufficient to rely solely on the analytical tools such as ventilation network analysis computer programs - these must be supported by the expertise necessary to conduct an accurate underground ventilation survey as well as experience of typical conditions to be expected in the evaluation of proposed extensions to a new or existing mine. When planning a new mine, the ventilation engineer can use the program to draw on a set of typical ventilation parameters, seam and proposed mining methods. These have been assembled as a result of numerous ventilation surveys conducted by ACIRL in New South Wales and Queensland.

Jan 1, 1983

By Barro L

Very large reserves of gas are contained in coal. Because of the low permeability of the coal gas flow rates are very low. Fracturing of the coal can be achieved by use of the nitrogen - foam frac techniques described but the flow rates after fracturing are not sufficient to support economic development. Fracturing of the seams in the Bowen Basin was as predicted but in the Sydney Basin no trace of the fracture could be found when development proceeded past the fractured well. Testing of coal samples has provided some insight into parameters affecting desorption Rates.

Jan 1, 1982

Australia has been an important producer of zinc minerals and metal for many years.Late in the last century Edgar A. Ashcroft, a versatile and enterprising electrical engineer proposed the treatment of zinc rich ores by roasting, followed by leaching to extract zinc, purification of the solution and electrolysis of the purified solution to produce zinc. Residues from the leaching operation were to be smelted in a lead blast furnace to recover lead, silver and gold.Ashcroft (1897-98) and (1898) has.given us a most interesting record of the attempts made at the Sulphide Corporation's plant at Cockle Creek near Newcastle, NSW, to put his ideas into practice. In spite of the best efforts of all concerned, including the use of electrolysis of aqueous chlorides and sulphates, zinc could not be deposited consistently and the project failed although lead smelting continued until 1922 (Woodward, 1965, p. 158). Based on later experience with Broken Hill materials the presence of undetected cobalt in the solutions was the likely cause of the inability to deposit zinc (Kirk and Othmer, 1956).

Jan 1, 1985

By Ham G. I, Just G. D

The model considers a range of design parameters and operating condit- ions and evaluates the significance of these in the ultimate design of a mine. It also considers organizational features associated with the mining method and examines the inter-dependence between operations. An important characteristic of the model is the use of both stochastic and deterministic methods to study the behaviour of the complete mining system. The simulator selects the appropriate unit operation, computes and records its time, performs it and then calculates the production and cost data. Output is in the form of shift, day, week or period repor-ts. These reports will indicate problem areas such as restrictions in the production network for a given set of conditions. The likely effects of alternative means of solving these problems can be evaluated by changing the original input. Such information could be used by the mine management to select an

Jan 1, 1974

By Lawless JV

Recent exploration for gold on the Pacific Rim has utilised similarities between active hydrothermal systems and epithermal gold deposits. The major control over formation of such deposits is the hydrology of the ore-depositing hydrothermal system, which varies depending upon its geologic setting.

Jan 1, 1987