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By T O Aspinall

The Australian mineral industry involves a diverse range of expertise and skills. Within that, the mining industry, representing mine planning, mine management and equipment operation, has capital intensive, high productivity equipment and a small but skilled workforce. Continuing education for all personnel in the workforce after formal school courses will be an important contribution towards improving competitiveness. The non-tertiary sector represents a significant proportion of the workforce and requires as much attention as the tertiary educated group. Competency Based Training is now being developed for the mining industry in Australia under the National Training Board and the mining industry is well represented in establishing standards and curriculum. TAFE is a major source of accredited courses but some mining companies are also developing internal courses not necessarily for external accreditation. Articulation of such accredited courses to tertiary mining engineering courses has been considered. The education and training of equipment operators through continuing education requires attention to operating skills, an understanding of the productivity factors under the direct influence of the operator and providing product quality to the customer. The education and training of mining engineers has been widely covered and continuing close involvement of the mining industry is required to ensure well balanced courses in technical and interpersonal skills as well as motivation to continue learning for life. Postgraduate research is a part of continuing education but the mining industry has to continually address the adequate recognition of post-graduate qualifications for the increased technical or management expertise and the development of better analytical and problem solving skills which can be directed towards improving competitiveness. More attention has to be paid to providing adequate financial incentives to attract suitable students, particularly after attaining some experience, and to address their professional career path with a company so they are not significantly disadvantaged by undertaking post-graduate studies. The Chartered Professional Engineer status as provided by The Institution of Engineers, Australia to qualified candidates is being considered by The Australasian Institute of Mining and Metallurgy as a further recognition of a member's specific expertise and competence in mining and metallurgical engineering. Continuing education plays a major part in the maintenance of the expertise and competence required for a professional engineer to develop and also to retain chartered status. Continuing education will be a significant part of the education and training of all the mining workforce towards improving the competitiveness of the mining industry. The major challenges will be the motivation of all towards lifelong learning and the integration of the various programs towards providing the opportunity for a steady and satisfying career progression.

Jan 1, 1994

By W A. Tchernykh, R P. Strelnikova

In connection with the fact that technology of ore mining by caving system is often used when mining of deposits, characterising by low stability of surrounding rock mass, the main problem for such ore mines is ensuring stability of mine workings, placing in a zone of influence of winning operations. Besides natural disturbance of ore mass, stability of workings depends on the dynamic effect of blasting operations and also on the dynamic effect of structural blocks detaching from the ore mass and colliding with crests of ore pillars in the bottom of a chamber. Decreasing of dynamic stresses may be achieved by way of creation of a compliant porous screen or an ore cushion in the chamber bottom. It is established that maximum levels of compression take place when the first impact impulse occurs, and after that increase of compression of protective slice decreases. Necessary thickness of screen slice was substantiated theoretically with due account of height of structural blocksÆ fall, their mass, deformation modulus of ore mass and ore cushion.

Jan 1, 2003

Scheduling mine development and underground construction has been the bane of most mine managersÆ lives at one time or another. Even though scheduling software has developed significantly over the last 20 years, mining projects continue to take far longer than expected to complete. It would appear that possession of a gleaming 1000 activity bar chart generated by the latest project management software and plotted in multiple colours offers no guarantee at all that any of those 1000 activities will be completed on time, let alone the project as a whole. The author has earned his æmasters in disastersÆ with more than one project running over time and budget. This paper describes some of his experiences in scheduling major mine development and construction projects and the lessons he has learnt along the way. In particular, the paper examines a range of key issues that mine schedulers must take into account when planning mining projects. The paper also examines the development of scheduling software and particular advance rates used in scheduling mine development projects in Australia.

Jan 1, 2000

Milling Practices Ore is direct tipped into a gyratory crusher and crushed to minus 209mm and fed to stockpiles for the blending of grade into the mills. Secondary and tertiary crushing reduces the mill feed to minus 12mm. Mill feed is a blend of breccia and porphyry ore into two primary mills with the overflow to a regrind mill and then into the leach tanks, followed by a conventional counter current carbon in leach circuit. Underflow from the cyclones feeds back into the primary mills for additional grind. An unusual feature of the Mt Leyshon milling circuit is a desire to produce scatts. The scatt by product is the polished base rock of the Mt Leyshon Breccia clast and contains little grade. These scatts are produced because of the additional time and energy required to produce a proportionally small quantity of gold. The residence of these scatts in the mills decreases the mill feed rate. Scatts account for twenty percent of the mill feed and are screened from the discharge of the primary mills.

Jan 1, 1990

The Proterozoic Pb-Zn deposits of the Gulf of Carpentaria, Australia, include HYC (McArthur River), Mt. Isa, Dugald River, Lady Loretta and Hilton. Two seamingly incom- patible depositional models have been proposed to account for their origin. Finlow-Bates (1980), Large (1983) and Russell(1983) classify these-deposits as sediment-hosted submarine exhalative deposits. This class includes Rammelsberg, Meggen, Silvermines, Sullivan and others. In contrast, a lacus- trine, shallow-water origin has been advocated by Williams and Logan (1981), Logan and Williams (1984), Muir (1983) and Eugster (1985). The discrepancies between these two models can be removed by creating a separate class, that of continental sediment-hosted exhalative deposits.. HYC., Mt. Isa and Dugald belong to this class and their sediments were deposited in shallow, alkaline lakes. Metal- rich, hot, Na-Ca-Cl brines entered the basins along boundary faults and interacted with pore fluids and sediments, depositing-Cu-Zn-Pb sul- fides. Similar brines entered the Lady Loretta basin after marine flooding, depositing sulfi- des and barite, placing Lady Loretta into the class of marine Sedex deposits.

Jan 1, 1987

By Tyler MA

If the record of maj or proj ects in Australia is taken into account, it is apparent, the proper planning of an industrial relations strategy for many such projects has been ill considered by project developers. The recognition of the need to develop a plan from the initial feasibility study has been forced on those promoting new projects by the publicity given to the Australian industrial relations record. The delays in delivery caused by factors supposedly out of the project's control are often given for non-performance of contract and used as an excuse for limiting further development. Many of the problems experienced in project development can be overcome with sound industrial relations planning. The promises given in the euphoria of the early stages of a project relating to price and delivery often become a burden for the future because the complexities of the Australian Industrial Relations Systems are not understood or considered. The recognition by senior executives of their responsibilities in this area will contribute greatly to a new era of project development.

Jan 1, 1983

The rights of nations to explore and exploit minerals in the continental shelf were recognized by the 1958 Convention on the Continental Shelf. The Commonwealth Government has expressed the view that, as a party to the Convention, it has, by virtue of its foreign affairs power, full rights to legislate with respect to offshore minerals. States have taken the view that the rights recognized as extending into the continental shelf are land mineral rights, which belong to the States, and the Commonwealth legislative power in this field is strictly limited. Without prejudice to each other's rights, Commonwealth and States agreed to "mirror" legislation in relation to offshore petroleum. Commonwealth and State legislation, of which the operative parts are in identical terms, are both administered, in relation to areas adjacent to each State, by State Ministers of Mines. The legislation has functioned well in practice, though difficulties are encountered by the Commonwealth Government due to lack of direct accountability to Commonwealth Parliament. An alternative scheme designed to overcome this problem is outlined.

Jan 1, 1974

By J E. Everett

At BHP Billiton Iron Ore Newman Joint Venture (NJV) ore is railed from four separate mine operations in the Newman area to Port Hedland, where the ore is screened, crushed and blended to produce lump and fines NJV products. Each mineÆs grade varies separately, so it is important that a centralised system is in place to control the overall blend and ensure that the products meet customer expectations. It is important that grade- related decisions are built into the normal production process and have minimal impact on production rates. A continuous stockpile management system (CSMS) covering the whole NJV production process is used to generate the daily crushing schedule, taking into account all currently available ore sources. Innovative additions to the CSMS provide more accurate information to support decision making by the mine schedulers; for example, blasthole estimates are continually adjusted for bias compared to crusher and port rake grades; lump-fines (L-F) grade split and beneficiation plant upgrade algorithms are updated on a continuous basis, and the dilution effect, which impacts on reported port rake grades, is removed.

Jan 1, 2007

By W Farnworth, D Fergusson

Estimation of productivity is a key factor in the design of hydraulic mines and in assessing their economic feasibility. A published Russian formula for hydraulic mining monitor cutting rates overstated productivity by up to 2 tonnes per minute (251%) when applied to Solid EnergyÆs hydraulic mines. A new formula, taking into account additional productivity factors, was derived by Solid Energy and produced an acceptable correlation between predicted and actual cutting rates inNew Zealand and overseas hydraulic mines, with an average error of approximately 0.1 tonnes per minute.   Another key factor in hydraulic mine design is the transport of coal slurry via flumes. Solid Energy carried out a series of 80 full scale tests in a surface flume installation, varying the gradient and coal:water ratio. Both steel flumes and plastic-lined flumes were evaluated. A modification of the Chezy Open Channel Flow formula, including a factor for slurry density, gave a reasonable correlation between actual and predicted flows. It is believed that this Solid Energy formula is suitable for the design of flume installations for hydraulic mining.

Jan 1, 2004

By D Brennan, S Jahanshahi, F Jorgensen

The recycling of metals can be very efficient with careful selection of the material being recycled. The volume and value of recycled ferrous scrap has lead to the development of steel mini-mills which in turn has caused major changes to the steel industry. Although much smaller in volume, the recycling of lead is very significant, with battery recycling accounting for 60 per cent of annual world production. This high recycle rate can be attributed to the relatively uniform feed-stock from lead-acid batteries. The recycling rates of other metals are considerably lower due to longer use and non-uniform product usage that results in less efficient segregation and processing. It is clear that recycling of metals has advantages but its sustainability is uncertain. What are the key benefits of metal recycling? Metal recycling has technical, economic and social impacts. It is relatively easy to assess recycling on a technical basis, but the social impacts are harder to evaluate. This paper examines some of the issues in evaluating the sustainability of metal recycling.

Jan 1, 2002

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

Since 1865 when Congress moved to create a Federal Mining Bureau, successive legislations have given rise to the current '!Federal Coal Mine Health and Safety Act, 1969. Coal beds from 22 feet to 20 feet thick are mined under covers from 50 to 2800 feet with full and partial pillar recovery equally popular and accounting for a total of 54% of the mines. Pillar recovery and roof support practices vary, and each operator must submit an overall roof control plan (within specific guidelines) for approval before undertaking any development. The guidelines relate to dimensions of openings, details of support, sequence of extraction, limits of extraction and caving details. Experienced and professional staff of M.E.S.A. provide roof control plans and make inspections and grant-approvals of principles of support and minimum support in pillar extraction, with provision for modifications with time. Guidance is given with training programmes and standards of supervision. All of these aspects are approached in the spirit of the Congress declaration that the first priority and concern must be the health and safety of the miner.

Jan 1, 1974

The Joint' Venture Method is a procedure for assessing the value of exploration properties, particularly those for which resources have yet to be delineated. It aims to convert the terms of an actual or synthetic joint venture into the equivalence of an arms- lengths cash transaction between a willing seller and a willing buyer. This paper sets out one approach to achieving that conversion. It discusses both simple and complex cases and gives some examples from both public and private documents. It also includes some case studies in which the Joint Venture Method of valuation can be compared with values derived for the same project using other methodologies including actual cash deals. The Method has failings in both mathematics and logic. However because it does reflect or simulate an arms-length deal which takes into account past exploration effort and expenditure and an assessment of prospectivity at a particular point in time, it is felt that it can provide a reasonable approximation of trade value or asset value of a prospect, particularly if used in conjunction with other methods.

Jan 1, 1994

This paper explains why the valuation of mining assets is often a very different exercise from the valuation of the shares in the mining company which owns those assets. The fundamental reason for this is that mining assets, and the shares of the company which owns those assets have different risks. In order to properly value mining securities it is essential to: ò ensure all the different risks and other factors which impact on the value of the mining assets and the value of the shares are taken into account; and determine the extent to which the different risks and other factors are addressed in the value of the mining assets and the value of the shares so as to avoid double counting or not counting at all. If the alternative, but far from consensus, view is accepted that the correct valuation methodology to apply to shares in mining companies should be based on option pricing theory then conventional valuation practice of both mining assets and shares in mining companies will need to be fundamentally reassessed.

Jan 1, 1994

For decades strip mining with discon tinuously operating 'draglines and shovels has been the most economical operation method in the shallow hard coal opencast mines of Aust- ralia, North-America and some other countries. Continuously operating equipment such as bucket chain excavators and bucket wheel excavators in combination with conveyor belt systems, conveyor bridges and stackers had been deve- loped in Germany; during the last 25 years this type of equipment has been further developed in order to allow a high degree of rationaliza= tion as to opencast mines in unconsolidated overburden in Germany, in many European couh- tries, in India and in Victoria. The differing compactness of the layers to be mined, the increasing mining depth, the adverse over- burden to coal ratio and geotechnical con- ditions account for the combined use of con- tinuously and discontinuously operating equip- ment and systems. This paper is to demonstrate some projects showing the combination of continuously and discontinuously operating equipment which aims at optimizing opencast mine operations. It will be reported on the following combinations: - combined use of bucket wheel excavator/

Jan 1, 1981

By Choulaj D

Mining and petroleum continue to be the two most vita components of our nation's development, says Sir Julius Char in the Australian Journal of Mining (Nov-Dec 1996). In fact the} account for 71.6% of export earnings, and 21.2% of Gros; Domestic Product in Papua New Guinea. The Misima and Porger, Mines, along with the Kutubu oil project, have essentially rescues PNG's economic viability since the loss of income from Panguna Though the industry cannot create employment in the manner o. intensive industries such as agriculture, it does provid( opportunities to local communities in terms of jobs, financia compensation, and infrastructure. Many ventures take many years and enormous capital investment to set up. There are three phases: exploration, feasibility, an( operations. The operations phase sees a massive development o infrastructure, or the actual `building' of the mine. For mining companies to commit to such lengthy time frames and high level: of investment, without returns, requires confidence and a degree of commitment from government on a number of levels - legislative stability, monitoring social development, and the provision o social infrastructure.

Jan 1, 1997

An efficient filtration plant can be designed only from an adequate knowledge of the filtration characteristics of the material to be handled; if these characteristics can be expressed in the form of an equation the work of design is simplified immensely. The literature of the subject contains numerous equations which have been developed by various workers to express their results, usually obtained from a 'Very limited class of material, and from moderately thick pulps. Such expressions have been found quite unsuited for use in the case of thin, very free filtering pulps.In 1926, Underwood put forward an equation having a general for m, and which, he was able to show, provided a satisfactory expression of the data obtained and published by a large number of earlier workers. This equation has been found a very satisfactory and useful tool for the study of a variety of filtration problems. As thel basis of the equation is of assistance to the understanding of subsequent discussion, a brief account of Underwood's derivation is given here.UNDERWOOD's FILTRATION FORMULAEThe following symbols are used:

Jan 1, 1932

This paper examines the interplay between longwall support design/geometry features, operational controls and geological features on ground response. Experience from several investigations is used to demonstrate the influence of factors such as longwall support capacity and geometry, setting pressure, coal seam strength and stiffness, tip-to-face distance and hydraulic supply and control system parameters on longwall ground response. These factors are then used to outline the requirements on key controls such as retreat rate and cutting height and their influence on allowable roof convergence. The ground response curve concept as a means to provide graphical representation of longwall support and strata interaction processes is presented. The approach was developed to address the requirement for a practical longwall support evaluation and selection tool that can take account of support load influences such as changes in roof geology or cover depth. An example of the comparison between single pass longwall and top coal caving in a thick seam environment is given to demonstrate the influence of the various factors discussed.

Jan 1, 2005

Mining in Guyana dates back into antiquity and a brief history of gold and diamond mining and of the small-scale miner, the pork-knocker, is given. The gold and diamond deposits found on the beds and in the flats of old and present rivers and the current methods of investiga- ting these deposits are briefly described. Methods of mining these deposits including the small-scale hand methods of pitting and diving with or without helmets are also briefly described. 'The small-scale method of dredging using a suction dredge in conjunction with a diver is described in more detail, from its develop- ment to current practice, without giving too much mechanical and technical details. The organisation of the industry and the mining titles, laws and policy relating thereto are reviewed. A brief account is given of the socio- economic role of the industry. Conclusions are made regarding the need for improvements in existing equipment and financing and for incentives to stimulate production. The future outlook of the industry is con- sidered.

Jan 1, 1986

Drill and blast operations account for 12 - 15 per cent of total mining costs. This paper looks at a comparison between electronic detonators and non-electric detonators, focusing on the cost benefits associated with the high precision of the timing sequences of electronic detonators. An analysis of the total mining costs was made on two main case studies; one on a quarry in South Australia (Martin, 2007) and the other on a project undertaken at Sunrise Dam (Vaughan et al, 2007). The criteria used in the analysis included; the resulting fragmentation, a vibration analysis, crusher throughput and productivity analysis such as excavator cycle times, dig rates of the excavator and bucket fill factor. The results indicate that there were consistent production improvements and hence reductions in total mining costs attributed to the use of electric detonators. An increase in the degree of fragmentation gives lower crushing costs as more material passes through as undersize. This reduces truck delay time at the crusher, which in turn gives higher truck and shovels productivity as well as higher dig rates for the excavators.

Jan 1, 2008