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By Morgans DJ

The aim of this paper is to highlight the social aspects involved in the preparation of environmental impact studies (E.I.S.'s) for mining developments. In particular, the paper will reveal that the social information provided in such E.I.S.'s can achieve much more than simply satisfying government requirements. Such information can form the basis of a strategy to deal with the settlement of a mine workforce in either an existing or newly developed community. A strategy of this type can go a long way towards avoiding many of the social problems and related industrial disputes often created in such circumstances. It will also be of significant benefit to the mining company in negotiating its infrastructure package with the local authority.

Jan 1, 1987

By Rintoul AH

Studies of many types and purposes are being carried out constantly by mining, minerals processing and other operating companies. Frequently, the staff requirements and special skills lie outside the resources of the operating companies, and needs arise for external consult- ing services. We examine the natures of a range of studies, the factors that influence whether they be carried out in-house or externally and then discuss the manner of execution. Aspects of both good and bad practice are highlighted in order to arrive at the basic principles that give the most benefit from study work. While the bulk of the discussion relates specifically to the execution of external studies of process plant projects, many of the observations can be applied equally to the execution of studies by one department of a large organisation for another, and also to studies of capital projects other than those involving process plant facilities.

Jan 1, 1975

This paper intends to give an insight into what is often considered to be a poor relation of the mining industry but is in fact an integral part of any community. Aggregate production accounts for more than half of the world production of minerals by weight. In New Zealand production of aggregates runs at around five tonnes per capita per year, making it a significant industry. The industry in this country is dominated by smaller operations close to the market due to the widespread population and relative abundance of aggregate. The Logan Point quarry is one of the largest quarries in the South Island with an annual production of around 250 000 tonnes. The market is mainly based around roading and building in the Dunedin area with some higher quality specialist aggregates being used allover Otago. The quarry has been owned and operated by Palmer and Son Ltd for 106 years with a fifth generation family member the current quarry manager.

Jan 1, 1992

By C D. Ogg, P B. Pope, K M. Lynch, B K. C

Iron-reducing bacteria are able to couple the oxidation of an electron donor to the reduction of Fe(III) to Fe(II) under anaerobic conditions in the generation of cellular energy. Recent evidence suggests that these bacteria are phylogenetically diverse and widely distributed in nature. Our laboratory has isolated thermophilic, thermotolerant and mesophilic iron-reducing bacteria from numerous petroleum reservoirs with varying conditions, groundwaters of the Great Artesian Basin (GAB), and petroleum-contaminated soils. Some of these isolates have been identified as novel species and from genera such as Deferribacter, Bacillus, Alkaliphilus, Clostridium and Thermoanaerobacter. Further investigations have shown that these bacteria are metabolically diverse, not only capable of reducing different metal species but also able to use a range of organic compounds, including polycyclic aromatic hydrocarbons, for growth. Due to their abundance and metabolic capabilities, it is possible that iron-reducing bacteria may be important in microbially-enhanced oil recovery processes and in the bioremediation of contaminated soils and aquifers, particularly in anaerobic zones.

Jan 1, 2004

A great part of the research on froth flotation of gold ores deals with ores containing gold associated mainly with sulphides, resulting in a largely accepted view that what takes place with sulphides (eg pyrite) in a flotation cell also happens to gold particles. This paper is concerned with the influence of some inorganics (CuSO4, CaO and NaCN) on gold particles flotation, using ethyl or amyl xanthates as collectors. The bench-scale tests were carried out with ground quartz and gold particles mixtures. Some findings stemmed from this study: flotation of the gold particles of size 0.16 mm was efficient adding only frother; larger gold grains were better recovered by the use of stronger collector CuSO4 did not seem to be an activator for gold; the addition of NaCN up to 200 g/t or CaO up to 2000 g/t did not depress the gold grains when amyl xanthate was used as collector although with ethyl xanthate the gold depression was verified.

Jan 1, 1993

Having successfully applied computer techniques to open pit mining applications, many software developers are now using their skills to tackle the much harder areas of underground mine design, planning and production.Dramatic improvements in the performance to price ratio of hardware (including high resolution graphics screens), a better understanding of the techniques of surface and solids modelling (and their subsequent display), moves towards standard user interfaces and advanced concepts of representing grade distribution in the ore body have all contributed to the recent increase in underground mining software activity.This paper details the general requirements of a workable underground mining software system, providing a minimum checklist of desirable features and emphasises the importance of ease of use, flexibility and intuitive feel. Some relevant trends in hardware, software and application techniques are highlighted and comments made on areas which require further development or are only available in a small number of packages.Finally, a comment is made on the role of computer models to provide a unifying medium for tying together all aspects of underground design, planning and production.

Jan 1, 1992

Most mining projects will involve some level of financial markets price risk. This is because commodities are generally traded in $US. The project will also incur costs in $A and if based in Australia will seek to generate a return in Australian dollars. Therefore the project faces commodity, foreign exchange and interest rates risk. As a business you may wish to maintain these risks within your business. However if the project requires financing to be provided then the financiers will want to ensure that there is a level of certainty attached to the cash flows to support the debt repayments. This is achieved by hedging the financial market risks. Traditionally the hedging process has been based on underlying assumptions within project models, which incorporate views on the direction of the underlying price risk. These views can be formed in an ad hoc manner. Gathering information from a variety of sources including economic forecasting and modelling, technical analysis, seeking market expert views. However, given the historical accuracy of such forecasts locking into long-term fixed hedging arrangements can create an inflexible environment that can restrict the opportunity to benefit from the underlying volatility of financial markets.

Jan 1, 2003

By Premur V

In industry and power production and distribution large quantities of fine wastes are produced. These are above all fly ash and phosphogypsum. Attempts are made to use them as secondary raw materials in industry and construction. Since they contain dangerous and harmful components or are nonhomogeneous their direct application is limited so that they are treated as waste. This paper reports on tests conducted with the aim of agglomerating the mentioned fine industrial wastes by pelletisation. The aim of this resarch was to obtain agglomerated product suitable for handling, transport and dumping. At the same time efforts were made to incapsulate harmful components by producing pellets with protective shells. Next, pellets without binders and with different binders were produced. Strength, resistance to freezing and solubility of pellets were tested. All the fine industrial wastes under survey were found to be suitable for pelletisation. The utilisation of appropriate binders ensures pellet strength required for safe handling and ecologically sound deposition of pelleted Material.

Jan 1, 1993

By Martin R. E

L44 Shaft is a major upcast ventilation shalt in the hanging wall of the 1100 Orebody. Various techniques for stripping a raisebored pilot hole were combined to produce L44 shaft. From the surface to 198 m depth, the shaft was concrete lined 7.3 m internal diameter. Below this the shaft was developed to 7.6 m diameter unlined. 11 level, 540 m below the surface, was the first readily accessible level connection. The section to 198 m depth was benched and concrete lined through weak oxidised ground. When more competent ground was encountered the operation was converted to horadiam stripping. This application of the raiseborer has led to a safer, more efficient method of shaft development.

Jan 1, 1977

Today's emphasis on the enterprise bargaining process must be seen as an opportunity for organisations to further develop occupational health and safety standards at work. In particular, this shift from a centralised industrial relations system to employer, employee bargaining, presents organisations with an excellent opportunity to develop OH & S at the `shop floor' level. This is despite real difficulties in presenting hard data on the cost benefits. Unfortunately, examination of enterprise agreements ratified by the Australian Industrial Relations Commission (AIRC), show that less than 32 per cent contain provision for occupational health and safety. Those addressing the issues of occupational health and safety have included segments such as: ò rehabilitation activities; ò a new emphasis for workplace occupational health and safety committees; ò formalising procedures related to hazard identification and control; ò the use of personal protective clothing; and ò occupational hygiene and health monitoring issues. For example, an enterprise agreement reached between CIG-Gases and their unions, included clauses which commit employees to attending ten safety meetings and two work place inspections each year, in order for them to receive any further pay rises.

Jan 1, 1995

The concept of "profit" is implicit in the definition of an ore reserve. It is suggested that the flexible concept "economic" is more appropriate. This allows different economic considerations to be taken to account when determining what is ore at the feasibility study stage; during actual mining production; before mine closure; and from the viewpoint of the national economy. Economic factors which are highly variable, and largely beyond a mining enterprise's control, affect the economic exploitation of a mineral resource. Major economic factors include: metal prices; operating costs; the cost of original and replacement capital equipment; the cost of capital; taxation and royalties; inflation; exchange rates and the state of the world economy. The paper suggests why a careful quantification of the average value, trend, and variation from the trend of major economic factors should be made and how this will lead to a better definition of ore reserves. The paper also discusses the necessity of reappraising economic factors during the life of a mine in order to maximise the economic surplus and to minimise the wastage of natural, economic and human resources employed in mining.

Jan 1, 1979

Australia is a leading producer of mineral sands and according to U.S. Bureau of Mines, produced 24, 53 and 64% of world's production of ilmenite, rutile and zircon respectively in 1983. The industry which is mainly export oriented earned in export income about $210 million in 1985. The dominant position which Australia occupies in world produc- tion of mineral sands is also maintained in many areas of research and development work on the processing and application of these minerals. Some of this research which is leading the world has been responsible for setting up industries to produce value-added and high-tech products such as synthetic rutile and partially stabilized zirconia (PSZ). The production of high purity zirconia is due to commence shortly while research in rare earths offers an exciting prospect for future Developments.

Jan 1, 1986

Efficient performance of pulp lifters to discharge ground rock is critical to the effective performance of SAG and AG mills. The paper covers developments in the design of pulp lifters and associated grates, of both conventional straight-radial and curved types, and of the inner discharge cone. Issues covered include the discharge performance of both the slurry and rock components of the discharge, reverse flow back into the mill through open grates and backflow down the pulp lifters of material that fails to discharge from the mill. The design experience is interpreted in the light of developments in particle flow modelling of the flow of charge in pulp lifters.

Jan 1, 2004

By Staude W, Rosser A

Due primarily to the publication of the Fitzgerald Report the impact of taxation on the mining industry and the amount of taxes actual- ly paid by the industry have become items of intense debate. However, the discussion has been governed more by impassioned rhetoric than considered logic. It is equally as wasteful to the economy for the mining industry as a low cost efficient export earner to be punitively taxed, as it is for the industry to be given excessive taxation assistance. A comparison of the effect of five tax- ation policies on the cash flow of a capital intensive mining project is presented. The policies considered are Liberal 1969, Liberal 1976 with and without the coal levy, Labor 1975 and Labor 1976. The mining project used in the analysis is modelled on published estimates for the proposed Nebo coal project. The analysis is equally applicable to any large mining or petroleum development.

Jan 1, 1977

By Woods PW

Consulting Engineers have been used in the mining and metallurgical industries for many years. The traditional role of the consultant overseas has been one of assisting with conceptual design right through to con- struction and commissioning as well as on occasion acting solely in specialist fields. This role developed because mining companies wished to concentrate on building up the permanent organisation they require to operate their mines and treatment plants without the traumas of increasing staff for the design and construction period and reducing it on completion. In Australia where there have been few individual minerals projects of magnitude (until recently) companies have looked after their own detailed engineering and construct- ion management employing consultants mainly in specialised fields.

Jan 1, 1975

In order to achieve optimum results for money spent in construction of new projects there is a need for mining developers to pay greater attention to cost control. Control is achieved by establishing a frame of reference, a method of checking and a means of remedial action. The frame of reference is a well coded set of budget estimates which graduate into definitive estimates as design is completed, backed up by drawings, specifications and bills of quantities. The method of checking is provided by cost engineering and quantity surveying input, at both feasibility study and design and documentation stages. Remedial action follows if the checking process reveals a need. In large complex projects where construction completion time is often of prime importance, control of costs can sometimes be relegated to second place. To avoid this it may be necessary to include specialists in cost control in project management teams. Quantity surveyors are trained specifically in construction economics and can provide develop- ers and project engineers with valuable support at all stages of construction.

Jan 1, 1983

The techniques used in evaluating gold placers and in recovering gold therefrom are briefly reviewed and critically assessed, relative to the estimated and actual recoveries from many operations. The discrepancies between these quantities can be significant and sometimes disturbing. The coefficient of variation for the annual percentage recoveries, relative to the estimates, is in excess of 10 and commonly above 20 . The difficult- ies in evaluating placers are recogni- sed both in the gathering of meaning- ful sample data and in the derivation of estimates. There are deficiencies, perhaps insurmountable at reasonable cost, in the techniques used to derive an estimate and in the gold saving devices usually employed. There is a subconscious trend to use recovery as a check on the estimate. The industry could have extracted more information during the evaluation and working of deposits in order to fully characterise them and in order to quantify metallurgical efficiency. There is a place for other prospecting techniques, particularly geophysical, in placer evaluation and a need for more appropriate and sophisticated

Jan 1, 1976

In this paper the reactions which may lead to particle hydrophobicity/hydrophilicity as a function of grinding environment-are reviewed. The results of pulp chemical investigations related to a Cu-Pb-Zn ore on a pilot plant scale and laboratory tests with a Pb-Zn ore to evaluate the effect of some inhibitors on grinding/flotation are presented. The flotation recoveries of the ores treated by conventional and autogenous grinding methods show only a marginal difference and the results favour autogenous grinding. Iron originating from several sources manifests in the form of insoluble hydroxy complexes in the pulps. Such metal hydroxy complexes are hydrophilic and coat the mineral surfaces indiscriminately. On the other hand, selectivity is a problem for pulps ground by autogenous milling. Some corrosion inhibitors used in the laboratory grinding/flotation tests on a Pb-Zn ore showed maximum reduction in the wear of the grinding media ranging from 25 - 36 per cent, depending on the type and concentration of the inhibitor.

Jan 1, 1993

By M A. Faizulin, N G. Stukalova

The present till now practice of averaging of ore by metal content at mining-dressing enterprises does not allow evaluating objectively really existing regularities of dressing process. The processing of large statistical data by specially designed methods has revealed the relationships of extracted mass of metals into concentrates when processing of ore at preparation plants. The analysis of the obtained relationships points to necessity of timely control by flows of ore with due account of different sorts of metal. For this problem solving it is offered to use specially designed methods on carrying out of calendar planning of a mining and shipment of ore at open casts, based on ranked arriving of flows of different sorts ores to preparation plant. The given methods includes economic-mathematical model forming and its implementing by worked out method. The formed model allows taking into account different technological and organisation limits, typical operation conditions of open cast and preparation plants. Using this methods of control of mining operations and designed on its basis the complex of software allows increasing volume of metals, extracting into concentrate, up to two per cent without any additional costs and saving of the existing technological schemes at preparation plant.

Jan 1, 2003

Pajingo Gold Mine Pty. Ltd. is a subsidiary of its United States of America parent the Battle Mountain Gold Company. Battle Mountain Gold Company was created in August 1985 as a spin-off of the United States of America Pennzoil Company's gold interests.Pajingo Gold Mine Pty. Ltd. currently has its headquarters and base for operations located in Townsville, Queensland. The Company's main current activities are the exploration and evaluation of the Pajingo Gold Property situated some 50 kilometres south-east of Charters Towers and in the northern Drummond Basin.The discovery of the Pajingo gold mineralisation by the Company was the indirect result of a regional program established to evaluate Carboniferous age volcanic plugs in north Queensland for gold mineralisation.

Jan 1, 1986