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It is no longer possible to establish a quarry on the most convenient hill then abandon the site, leaving a scar if the stone or sand in the deposit is found to be unsatisfactory. Before approval is given to operate a new quarry, the relevant authorities require a detailed plan of operations from commencement to final rehabilitation. To prepare this plan, a thorough know- ledge of the quality and size of the deposit is required. To obtain this information, the industry must use the most modern techniques available. Many examples can be given showing problems which have affected the smooth operation of a quarry for many years because the initial exploration was poorly carried out. The factors which must-be considered when exploring a deposit are detailed in this Paper.

Jan 1, 1979

Economic mathematical methods have been developed and applied in the design, planning, development and managing stages in the mining industry. Economic and technological efficiency is achieved with the aid of a large range of probability models, which are used to enable decisions to be made progressively during the different stages. The entire operation is considered as a total system made up of sub- systems and the models representing these are consecutively interrelated with each other. Algorithms and programmes representing the economic mathematical models for all the stages involved were tested and were found to be applicable to the various important mines in the Donetsk basin. Currently, these models are accepted and widely used.

Jan 1, 1977

By Dalmijn WL, Valk HJLvd

At the Faculty of Mining and Petroleum Engineering, the Department of Raw Materials Technology, a mathematical model has been developed to predict the porosity distribution in an uniform jig bed. If the porosity distribution in an uniform jig bed is known, it is possible to correlate this to the settling velocity of particles with a density different from the density of the bed grains and thus model the stratification in a jig. For measuring the porosity distribution in the jig bed a method has been developed based on light absorption techniques.

Jan 1, 1993

By Watson D. F

P S B Stewart has rightly pointed to a possible obscurity in our paper on drilling patterns, viz. in comparing the improvement of a triangular drilling pattern over a square one, we used percentage improvements without always making clear their base. We hope, however, that other readers, like Stewart, have been able to understand the particular meaning from the context.Although different methods of estimation of an ore deposit will have different local bias (Philip and Watson, 1985), the critical relationship affecting the reliability of estimation of an unsampled location is the scale of local variation of the variable being estimated in comparison with the density and isotropy of sampling. This relationship overrides all other considerations.

Jan 1, 1985

By Gluch KD

The current Mining Act has been the mechanism for administering and encouraging the State's mining industry through the 1970's up to the present. Although it has been subjected to considerable amendment there continues to be judicial challenge as well as criticism in relation to ambiguity of interpretation. Expansion of the mining industry and pressures placed upon "it by the ever increasing interaction with other land users have highlighted deficiencies in the current legislation and the need for a strong and progressive Act covering the rights and obligations of miners and their relationships with those outside the industry. - It is considered that the most positive results can be achieved by a complete redrafting of Queensland's mining administrative legislation.

Jan 1, 1987

By T S. Fayram

The successful application of flotation is now over one hundred years old. However in a practical industrial sense, it still remains predominantly an art rather than a quantifiable science. Moreover, the laboratory testing, interpretation and application of the technology can still be tedious, time consuming and costly. This paper outlines the use of proven statistical design of experimentation software for rapid optimisation of flotation testing with limited representative sample utilisation. This results in less costly required testing, a more thorough understanding of results and the ability to simultaneously optimise several variables and outcomes at once. At the Center for Advanced Mineral and Metallurgical Processing, this testing methodology has been used successfully in many metallurgical development and plant optimisation projects thereby confirming its real world utility and application.

Jan 1, 2005

By C Rees, M Predebon, J Denney

It has been said on many occasions that æthe future of the mining industry of Australia, and indeed the world, lies in the hands of the studentsÆ. As a student, this can be a daunting, yet very exciting, statement. If nothing else, it is a direct challenge to the student body of the mining industry to take responsibility for its direction æafter 2000Æ. However, for the students to embrace this challenge, some responsibility must be borne by the universities and the industry itself to provide some direction and encouragement. Perhaps, therefore, the real challenge is to find the right balance between students, industry and education to best prepare the students for a career in the mining industry. The future industry will demand students who are capable and willing to adapt to change and technology and able to exert the vision and leadership required to ensure the mining industry continues to thrive well into the next century.

Jan 1, 2000

There is no good news! The market environment for raising capital for resource projects is getting tougher. The regulatory and accounting environment is fast becoming more difficult and the hurdles to successfully raising debt, lease, equity or hybrid finance are now considerably higher. As ever, well structured companies and capital issues can and will survive, if not thrive. An outline of the market and regulatory environment for successful issues is set out below, followed by some comparison of stockmarket values of resource assets compared to more technical appraisals.

Jan 1, 1990

Whether you are an employee, contractor or consultant working in the mineral industry, there are pressures to deliver the best possible performance. Technical professionals are usually driven by an internal desire to perform to a high standard because of personal pride in their profession, but there are an increasing number of external requirements to demonstrate that the actions taken were based upon reasonable grounds and that the work conformed to current best practice. People expect these best practice procedures to be followed and governments are now requiring those tendering for contracts to be registered in some way and to be participants in quality assurance schemes. One is not immune to these pressures just because you are working in a less legislatively sophisticated developing country in the circum-Pacific rim (Pacrim) region.

Jan 1, 1995

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

This paper will review the experiences of both big and small exploration/mining companies (local and foreign investors), including the impediments to exploration and project development in Indonesia since the Contract of Work was first introduced there (1967 Minerals, 1981 Coal). This is seen through the eyes of a person who has been employed in a managerial capacity in large and small concerns, and more recently as an independent consultant. Comment will be made on the political, legislative and social constraints imposed by the presence of a large group of disparate artisans (illegal miners) who now form a significant component of the Indonesian mining industry; the Bre-X debacle; the impact of the recent Regional Autonomy legislation; and changes to the Mining, Forestry and Environmental Acts. An overall view (including statistics) will be presented as to how recent Indonesian developments have affected international confidence in investing in its mineral sector over the past decade and it will be placed in an international competitive context.

Jan 1, 2004

Most Geologists have a well rounded knowledge of the exploration phase and those who have worked as mine geologists have an understanding of the production phase. Few have had exposure to the development and the construction phases. Even fewer have had the experience of closing a mine, disposing of the plant and equipment, carrying out the final cleanup and making the area safe and environmentally acceptable.During the various phases of exploration, the geoscientist gains a wealth of non-geological information which can be of considerable value to engineers and technicians in the feasibili-ty, development, operation phases and finally the closure of a project. Such basic controls as surveys, adopted assay sample lengths and the location of items of infrastructure during exploration, may continue to affect the project through its entire life. Thus the geologist's responsibilities extend well beyond the explo-ration phase of a project.

Jan 1, 1990

By Robson L. C

The developing countries whether they be in Africa, Asia or the Pacific, are a potentially vast market for the technologies of the more developed countries.Conducting business in the less developed countries however requires a keen understanding of their culture. A keystone of the culture of the Pacific Island Nations is kinship with the land. Without an appreciation of the implications of the land rights debate, a business venture into these countries is likely to be delayed or even doomed to failure.The European heritage, with its notions of private ownership of land, have frequently been a stumbling block to a proper understanding of the concepts of customary lands. According to our laws, ownership of land confers a number of definite rights: principally the right to use the land, the right to exclude others from its use, the right to transfer it and the right to receivF income from the property independent of use.

Jan 1, 1990

By McGregor GW

The Utah International group of companies has a wide geographic spread of operations, including a significant interest inAustralia's largest coking coal operation in Queensland, steaming and coking coal mines in USA, a copper mine in Canada, a half interest in an iron ore operation in Brazil, a number of smaller operations, and a significant portfolio of undeveloped properties in South America, South Africa and South East Asia.The opportunity to acquire this group of companies presented an immediate problem to BHP in that it was regarded as too large for BHP to absorb by itself. In addition, there was a concern that such an acquisition would increase BHP's coking coal exposures to unacceptable levels. Despite these dilemmas, BHP was keen to acquire Utah.A plan was therefore developed and agreed to by General Electric (GE) (the then owner of Utah) which would give BHP nine months in which to put together a consortium to share in the ownership of the Queensland coal assets (plus coal assets owned by BHP), and to arrange a project financing for use by BHP and the consortium. BHP would own 100% of the rest of the assets.

Jan 1, 1985

As a society, the retiring age of workers is increasing. Individuals are having to consider working to an older age (beyond 55 years), the reason being to æpay offÆ debt, maintain a quality of life or, as a bigger picture, because society simply cannot afford the aging population. The Government is encouraging and promoting those approaching retirement to work to an older age to alleviate the financial burden of an aging population. In a working context those aged 55 years and over accounted for ten per cent of the Australian workforce in 1998 with this age group expected to account for half of the growth in the workforce between now and 2016. For the 60 - 64 years which account for less than three per cent in 1998, this group is expected to account for 15 per cent of the growth in the same period. As a result of individuals who have worked all their lives and in some cases æphysically hardÆ, they do not fully enjoy their years of retirement as a time when they get to choose what they want to do rather than what they have to do. Of particular interest are the physical or health related conditions that individuals end up with and the restrictions that ensue resulting in an individual being incapacitated either physically or with respect to the state of their health.

Jan 1, 2005

The ""comparable sales"" method of valuation attributes value to an asset by reference to actual sales of comparable assets or to the market capitalisation of companies with comparable assets. This methodology is widely used in real estate valuations. The real estate approach can be used to value mining and exploration properties where there are actual sales of comparable or similar assets in the recent past. The practical limitations of the comparable sales method are well known and self evident: limited number of transactions, limitations on comparability and inadequate data. The real value of the comparable sales method is in its use as a validity check. Estimates of value of mining and exploration assets are so sensitive to so many variables that all valuation methods have limitations. Accordingly there is real value in attempting to establish benchmarks from comparable sales. Apparently sophisticated valuation methods can mislead by creating the impression that valuation is a precise science. The judgement of the valuer is critical and judgements can be wrong. Any available evidence from actual sales that are even remotely comparable can provide useful input to the valuation process.

Jan 1, 1994

By G Huggins

Excavation in underground jointed rock masses creates cavities into which the surrounding rock mass deforms. Deformations, besides intact rock deformation, include mechanistic deformations such as slip and rotation. In this paper deformational moduli were measured for prototype and blocky (jointed) models using elastic analogue methods for stopes from MIM LimitedÆs Lead Mine. The blocks for the models were defined in terms of the prototypeÆs joint sets, their spatial separations, orientations and average friction characteristics. From dimensional analyses, a relationship between prototype and model deformations was used to predict stope mid-span deformations. The results of this physical modelling work, conducted in the 1970s, motivated an investigation into the electro-treatment of tailings backfill to achieve improved strength and stiffness characteristics. Tailings backfill containing fines and having a high clay content can be electrically dewatered, and at times grouted, cemented, ion exchanged or agglutinated, to achieve relatively high magnitudes of strength and stiffness. These treated tailings stiffnesses can reduce the deformation magnitudes within a rock mass and, in doing so, reduce problems encountered in mine pillar extraction. The application of these tailings modification techniques is examined in relation to the elastic analogue methods.

Jan 1, 1998

Modern technology and the need for published results have created the tendency for exploration to concentrate on drilling and assaying rather than building a broader geological understanding. Though grade is vitally important to a resource estimate, density and volume are also very important aspects that require equal consideration. Wet tropical nickel laterites are developed in humid environments over ultramafic bedrock where the nickel and cobalt are enriched to economic levels by weathering, leaching and supergene processes. These laterites often occur over rugged terrain at higher elevations where there is sufficient rain and stability for the long lateritisation process to occur. For nickel laterite profiles, the variable terrain and significant material type changes within the relatively thin profile make density and particularly volume estimation, just as significant as grade in resource estimation and assessment of resource risk. Drilling alone is generally not a cost-effective way to reduce the risk in laterite volume estimation to acceptable levels. Surface geological mapping, high resolution topographic data and other information such as ground penetrating radar (GPR) can be used very effectively to improve volume estimates. These data types are all differently structured, have different data density and quality and may potentially overlap. Integration of these disparate data types provide the most cost-effective approach to modelling wet tropical nickel laterite volumes and minimising risk. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

To meet the objectives of sustainable development, mining projects must be executed with minimal environmental risks and impacts. To allow proper actions to be taken, it is helpful if the environmental challenges associated with a mine development project can be predicted early during exploration activities. Signs of impending environmental problems like acid rock drainage and metal leaching are often revealed in the occurrence of natural acid drainage, formation of efflorescent salts and their associated ecological effects. Other subtle clues can be deduced from anomalous geochemistry, detailed textural features of mixed sulfide assemblages and miscellaneous environmental data sets covering the target areas of exploration. A more practical tool, however, is the development of comprehensive environmental ore deposit models containing relevant information on ore genesis, applicable mining, processing and waste management options and their environmental implications according to deposit type. Not only will such models facilitate communications among independent groups of personnel involved in a mining project to come up with schemes to ensure better environmental performance of the overall project, they will also facilitate decision-making if a mine development project should be pursued further or valuable resources be redirected to other more favourable targets.

Jan 1, 2003

By Boyd G

Deep mining in the Collie Basin has suffered with high levels of water flow and sediment in-rushes throughout its 90 year history. Current day experience in working conventional bord and pillar by mainly mechanised means is that advance to the dip is impeded at about the 150m depth of cover by excessive water flow and pressure bursts. Extensive analysis of exploration borehole data and reconstruction of depositional environments helped define important hydrogeological characteristics of roof and floor aquifers, aquitards and aquicludes. Hydraulic parameters were estimated with some accuracy using indirect methods, and later confirmed by pump testing. Groundwater flow modelling showed that mine scheduling would have to be a balance between down dip and lateral development if aquifer pressure heads were to be decreased to suitable levels. Since pressure reduction in aquifers immediately above and below the mine opening was. identified as the key aim in groundwater control, a series of trial in-pit dewatering holes were installed, and demonstrated pressure heads could be reduced at rates compatible with a mine extraction sequence which, in turn, controlled the rate of down dip mine advance. A case history of the successful application of in-pit dewatering systems within difficult hydrological conditions for mining is described, with emphasis on the close collaboration required between hydrologists, mine planners and operations personnel.

Jan 1, 1988