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Programmes of environmental investigations to identify and minimise impacts and satisfy government and community requirements have become an integral and rate determining component in the planning and development of new mines in Australia. This paper reviews the essential features of the environmental project management Function.

Jan 1, 1983

By Costello MC

An alternative process for desorbing and recovering metals from activated carbon has been developed, and is the subject of several patent applications by Micron Research (W.A.) The system uses the principle of conditioning the carbon in a strong alkaline cyanide solution followed by distillation desorption in a fractionating column, using the carbon as the column packing and methanol as the desorbing agent. The system offers the following advantages : (a) The processes of desorption, methanol recovery and reactivation are all carried out in a single column with the carbon itself acting as the column packing. No other desorption plant items or fractional distillation equipment are required. (b) The metal values are concentrated into the water content of the carbon and no other water is used except as condenser coolant. This produces very high grade gold silver solutions which give high current efficiencies in the electrowinning step. These high gold concentrations allow almost complete separation of gold and silver from copper in the electrolytic cell. (c) The process is completed to a tailing assay of less than 200g Au/tonne carbon in 15 - 20 hours allowing turn around of carbon batches on a daily Basis.

Jan 1, 1982

By Kepplinger W

The KR Process is a joint development by VOEST-ALPINE, Austria and its subsidiary company KORF ENGINEERING, Germany. This new technology allows production of hot metal on the basis of non-coking coal. The KR Process is based on the idea of separating the process steps realized in the blast furnace (generation of reduction gas, reduction of iron oxide and melting of the reduced iron) and including coking of coal. These reactions are carried out in two reactors: - the melter gasifier, where non- coking coal is coked and gasified into a high quality reduction gas and hot prereduced iron is melted. - the reduction furnace, where iron oxide is reduced by the reduction gas generated in the melter gasifier and discharged in a hot state. In order to prove the process a pilot plant has been set up in Kehl/ Rhine in 1981 with a nominal capacity of 60.000 tpy.

Jan 1, 1986

By Massacci P

A review has been made of the studies focusing on methods for the description of grain -size distribution after breakage and, separa- tely, of the degree of liberation of the miner- al species making up the various grain-size classes of comminution products. The purpose of the study has been to de- velop an overall model of the phenomenon which, owing to the very effect of comminution, leads to the formation of grains that are generally of mixed composition. A calculation procedure has thus been de- veloped for the liberation function taken as the assessment of the distribution of mix com- ponents in the products obtained after a commi- nution process. The aim is to identify a func- tion which may, to a certain extent, simulate the variation of the grade-recovery function of an ore in relation to its degree of comminu- tion. The numerical model thus obtained has been tested out on results obtained experimentally.

Jan 1, 1986

By Gostylla W

The economic feasibility of controlled district cross-cut recirculation is examined in this paper with particular reference to the most important mine ventilation network parameters. An algorithm is developed to express the annual cost of recirculation which is then compared to the annual cost of conventional ventilation using the University of Queensland Experimental Mine as a case study. The concepts of resistance ratio and volumetric efficiency ratio are introduced and used to analyse the economic feasibility of controlled recirculation within a mine ventilation network.

Jan 1, 1988

By Frew J. A, Harris M. C, Manlapig E. V

The recovery achieved in a flotation process is a function of both the characteristics of the feed stream and the operating conditions within the flotation cell. In this paper, the flotation characteristics of the streams within the Red Dog le

Jan 1, 1997

The granulites and related "dry" igneous rocks tend to be passed over during exploration for metals. Preliminary data show that high trace concentrations of Cu, Ni and other metals of economic interest are common in orthopyroxene and some of the other granulite minerals. During retrograde metamorphism of granulites, pyroxenes are converted to amphiboles or phyllosilicates, and significant quantities of metals are released and become available for incorporat- ion into new mineral phases, or may be transported elsewhere. S--rich scapolite is the normal scapolite of granulites. Its retrogression to secondary plagioclase provides much S which scavenges Cu, Ni, etc., from pyroxenes undergoing retrogression, thus producing ore-fluids. A full analysis of a scapolite with 5.10 per cent S03 is given. Beryl is unstable in granulites but the rare Be mineral taaffeite (Al4Pf (Be,Fe)O3) with 5,50 per cent BeO occurs in central Australia as a pale green Tabular mineral easily confused for chloritoid in hand-specimen. Metamorphic differentiation and mobilization of primary ore concentrations are major factors controlling their post-granulite attitude and grade.

Jan 1, 1969

By Erickson M. E, Smith C. K, Carswell J. T

Thirteen holes totalling 3200m were surveyed using a downhole time domain Geonics EM37 system at the 830 metre level within the CSA Mine, Cobar, New South Wales, in order to search for blind, electrically conductive sulphides at some distance from exploration drillholes. A significant off-hole conductor was detected in only one drillhole.Geophysical modelling and interpretation of the survey results indicated that this off-hole conductor was caused by a sulphide lens 30 metres from the drillhole at a hole depth of 220 metres.

Jan 1, 1990

By Smith Z, Huppert P, Charbucinski J

The paper describes a spectrometric method and apparatus developed for lithology logging in brown coal formations. The nuclear spectromet- ric technique developed is able to delineate coal/sand/clay seams. One requirement was to log inside drilling rods, as well as cased or open holes. The method described is based on combined natural gamma and gamma- gamma techniques using a spectrometric system for signal acquisition and subsequent computer based on-line data analysis and interpretation.

Jan 1, 1989

The Mount Sisa orebody on Misima Island, P.N.G., consists of goldsilver mineralisation associated with massive carbonate and amorphous iron-manganese oxides in fractures and breccia matrix. The orebody forms the northern extension of the Umuna deposit, which lies within a three kilometre strike length of a northwest trending, 300 metres wide, high angle fault zone. The structure is deeply oxidised, with the magniferous oxide material resulting from oxidation of carbonate. The wallrocks are metamorphosed basement psammopelites and basic volcanic rocks, extensively intruded by microgranodiorite. These are dominantly epidotised and sericitised. The precious metals are associated with anomalous Cu, Zn, Pb, Mn, As, Ba, Ga, Sb, and Mo. Many of the features of the Mount Sisa mineralisation are characteristic of volcanic-hosted epithermal deposits of western North America.Lithologic and textural gradation is observed between the carbonate hydrothermal breccia-fill at Mount Sisa, and the quartz dominated brecciafill and dilational fracture-fill mineralisation which forms most of the Umuna deposit to the south. This gradational relationship is analogous to that in the Amethyst-OH vein system at Creede, Colorado, where it is shown to be indicative of deposition from laterally migrating fluids.

Jan 1, 1988

Most compact bucket wheel excavators in use are in the small to medium range. Large compact bucket wheel excavators compete directly with con- ventional longer boom excavators which have operational advantages over the large compact. There are, however, situations where the large com- pact excavator is viable. In the development of these large compacts there are a number of technical features to be addressed. In addition the SECV now propose to expand the concept to a large compact bucket wheel excavator with a bridge and loading unit for their Loy Yang Open Cut.

Jan 1, 1989

Draglines have been a significant part of world open cut mining since the early part of the 20th century particularly for the removal of overburden in the strip mining of coal. Since the mid-1960s draglines have played a major part in the large strip mining coal developments of Queensland and New South Wales.There are now over 60 large draglines operating in Australia ranging in size from 23 to 103 cubic metres bucket capacity, with digging depths to 60 metres, dumping heights to 50 metres and dumping radii to 100 metres. The application of these draglines has progressed through the uncovering of coal in shallow, single seam operations to deep multi-seam operations requiring a greater dependence on pre-stripping activities ahead of the dragline to remove overburden not able to be efficiently handled by the dragline.

Jan 1, 1992

The earliest suggestions that some metallic ore deposits might have resulted from seafloor volcanic exhalation seem to have been those of Elie de Beaumont in 1847 and Henry de la Beche in 1851. In 1885 Tinoco, and Bouglise and Cumenge, independently investigating-.the manto copper deposits of the Boleo district of Baja California, proposed that these had formed on the seafloor by precipitation from "hydrothermal submarine emanations". Some twenty years later the Japanese geologists Kukuchi and Tsujimoto (1904) put forward the idea that the Kuroko ore- bodies were seafloor volcanic sinter deposits and in 1919 this was re-affirmed by Ohashi. In 1909 the English geologists Thomas and MacAllister postulated a similar origin for some of the gold deposits of Mount Morgan in Queensland. Between the wars the great European economic geologists Niggli and Schneiderhohn both clearly recognized a class of seafloor hydrothermal deposits. The idea rose again immediately after the Second World War in a very clear statement by Hegeman in 1948, which was followed by contributions by Ehrenberg and Kraume and their co-workers on the submarine volcanic origin of the Meggen and Rammelsberg orebodies in 1954 and 1955 respectively. In 1955 the present writer, quite unaware of early or contemporary work on volcanic exhalative ore deposits, proposed a volcanic sedimentary/diagenetic origin for the stratiform base metal ores of SE Australia. In doing so the writer emphasized the probable importance of island arc volcanism, suggested that some "metallogenetic regions" of ancient terrains were in fact old island arc systems, that the composition of the ores might be related to the composition of the associated volcanic rocks and that such ores would be tied to volcanic stratigraphy. Ideas on relations between volcanism and stratiform ore genesis have thus been evolving over.a period of some 140 years and, beginning with the observations on Baja California in 1882, work round the rim of the Pacific has made an important contribution over a period of more than 100 years.

Jan 1, 1987

(Quality can be defined as that which is acceptable to the market and can be supplied with a predictable degree of uniformity and dependability at a low cost. The market for any mining product is downstream processing, whether it be an alumina refinery, a gold processing plant or a flotation plant. The cost of that downstream process is partly dependent on uniformity of its feed material both in physical and chemical terms. With more operations adopting procedures which require quality assurances in line with International Standards, from their raw material suppliers, miners must look to their grade control processes to provide uniformity and predicability.This is not a new concept. The mining industry has constantly been working with ahighly variable raw material supplied by Mother Nature, from whom we cannot demand quality assurances. Through the processes of exploration, resource and reserve definition, long and short term mine planning and day to day grade control an end product has been supplied which consistently meets our customers requirements, in an economic fashion. When any of these processes fail, then penalties are incurred which can range from increased mineral processing costs to loss of markets and in the ultimate case, failure of a mining operation.

Jan 1, 1992

By B Mil, D P. Adhikary, M S. Craig, P Rutzou

As shallow coal reserves with easier mining conditions are exhausted, future deep coal mining with difficult mining conditions may face significant economic, technical and environmental challenges. Moreover, due to increased coal production capacity with the new generation longwall systems, predicting adverse mining conditions has become more important than ever before. The potential impact of these difficult conditions is an increase in mining risks and costs. Reliable prediction of rock mass deformation, mine stability and mine water inflow is not only essential for improving mine safety and reduction of coal production costs, but it is also important for the assessment and management of the environmental impact of mining. This paper briefly describes an integrated approach to mine groundwater simulation and prediction. Central to this integrated approach is a three-dimensional computer code called COSFLOW, developed by CSIRO of Australia in collaboration with NEDO and JCOAL of Japan to address the pressing issues of mine water management. COSFLOW incorporates unique features that make it ideal for the simulation of coal mining and examining the interaction between rock fracture, aquifer interference and water flow. This paper also presents an example of an application of the integrated approach and COSFLOW in water inflow prediction at Springvale Mine in New South Wales.

Jan 1, 2006

By D T. Feinstein, M B. Gotkowitz

In Wisconsin, state laws and regulations governing metallic mine permitting stipulate that protection of groundwater quality be assured indefinitely through all phases of the mining project, including development, active mining, reclamation, and long-term closure. By rule, the Wisconsin Department of Natural Resources (WDNR) requires that permit applicants use a numerical model to assist in the assessment of compliance with this requirement for all proposed mine-waste facilities. As a part of the compliance assessment, model calculations are used to predict groundwater solute concentrations through time at designated boundaries for comparison to current groundwater quality standards. In practice, this modelling requirement has involved the application of numerical solute-transport models. Our review of a solute-transport model submitted by the developers of a proposed mine near Crandon, Wisconsin, provides us with an opportunity to assess the usefulness of transport modelling as a permitting requirement. Recent evaluations of solute-transport models by other workers suggest limitations in predictive accuracy. Our review of the model submitted for this project also identified important limitations due primarily to uncertainty in calibration of model parameters at the undeveloped site. The utility of any model to predict project compliance or non-compliance with numerical standards is limited by the range of uncertainty of key model parameters, such as dispersivity and porosity. Uncertainty in the future behaviour of the solute source(s) also reduces the predictive power. Moreover, the site characterisation provided by the model may have limited power to describe the site condition post-development. Although these inherent shortcomings accompany the use of solute transport models at undeveloped sites, the requirement for model development and the ensuing technical review has substantially assisted in our evaluation of site conditions and project design. Through this process we have identified elements of the waste facility design that are crucial to the environmental viability of the project, resulting in modifications to original project proposals. While results from this model review will be used to evaluate compliance, additional benefits come from the identification of critical design features that enhance groundwater protection.

Jan 1, 2003

By Radmuller H

The proposed underground mine at Porgera forms an integral part of the Porgera Joint Venture project in Enga Province in the remote Highlands of Papua New Guinea. The total in-situ reserves are approaching 400 tonnes of gold making the Porgera deposit one of the largest in the world. The remote, rugged and inhospitable terrain, recent unstable geological environment and primitive yet socially complex nature of the densely populated local community, combine to make the Porgera project very different to developing mines in Australia. The Porgera project is a challenging and exciting mining exploration venture in the final stages of feasibility study submission and negotiations with the National Government of Papua New Guinea. A 1476 m exploration adit was driven in the footwall of the high grade mineralisation for diamond drilling purposes as part of the evaluations necessary for the feasibility study. Ground conditions encountered have ranged from weak mudstones with high water content, requiring immediate steel set support, to competent intrusives.

Jan 1, 1988

Willemite mineralization was discovered in 1966 in the North Flinders Ranges of South Australia, in the course of a stream sediment sampling programme. Further work outlined a total of nine separate willemite occurrences in the Copley/Beltana area, and ten small deposits in the Toondana area south of Parachilna. Mineable reserves of 1 000 000 tonnes grading 36.8% zinc were outlined in three deposits in the Copley/Beltana area and campaign mining of the Main Orebody commenced early in 1974. The main group of deposits all occurred within red, dolomitized Cambrian Ajax Limestone, and most are associated with significant thrust faulting. The area of the Main Orebody group of deposits has been intensely fractured, and the surrounding dolomites are often brecciated and contain up to 5% zinc. Lead and arsenic mineralization are minor components of the main group of deposits. Masses of Middle Proterozoic Willouran Formation crop out adjacent to or close to most of the deposits in the Copley/Beltana area. The Willouran is frequently highly sheared, brecciated, and often contains large inclusions of younger formations. It is believed that most of the Willouran outcrops represent piercement structures.

Jan 1, 1975

The problem of instantaneous outbursts remains unsolved after over a century of events and the investigation of the mechanism of the phenomenon and means of treating it. Outbursts have occurred of up to 5,000 tonnes with perhaps up to 500,000 m3 of accompanying gas, either methane (CH4) or carbon dioxide (C02) or mixtures. The low density of CH4 and the high density of CO2 give particular problems. Australia with both gases has experienced outbursts for 85 years with fatalities as recent as 1978. The Bulli Seam of the Illawarra area of the Sydney Basin is affected and outbursts with both CH4 and CO2 occur. The Northern and Central Bowen Basin also experiences outbursts with both gases. Proneness of affected mines is related to the high rank of the'coal and the proneness of the seams-is localised according to depth, gassiness, structure and development geometry. Proneness may be reduced by appropriate choice of mining methods. In addition to outbursting mines other mines have symptomatic phenomena. Traditional preventive methods have been used and control by induce- ment has been practised. A method of local prediction for widespread use has not been achieved although locally successful prediction 1Superintendent Rock Mechanics and Strata Control, The Broken Hill Proprietary Company Limited, Steel Division Collieries, Wollongong, N_RW

Jan 1, 1980

By Toop G. W, Martin M. T

At the Cominco Ltd plant in Trail, British Columbia, the Betts lead electrorefining operation requires that antimony and arsenic be present in the lead bullion for anode slimes stability control. Until 1986 the antimony and arsenic inputs from concentrates to the Lead Smelter needed to be supplemented with high antimony and arsenic content recycles from the Silver Refinery operation to maintain a satisfactory composition. Subsequently the antimony and arsenic inputs have increased as a result of increasing levels of antimony in Sullivan lead concentrate and the purchase of larger quantities of silver/gold bearing concentrates that inherently have higher antimony and arsenic levels. The increase has exceeded the limits required by the Betts process. It therefore became necessary to install a partial softening process downstream of the Continuous Drossing Furnace to satisfactorily control the bullion composition. Process control and oxygen injection techniques used in the partial softening process are reviewed. Approximately 8 tonnes/day of softening slag are produced having a combined antimony and arsenic content of 25 percent. This slag is reduced in a recently commissioned short rotary furnace followed by vacuum distillation of the metal for recovery of the antimony and arsenic values.

Jan 1, 1989