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Gold mining commenced at Telfer in Western Australia in 1977. Ore mining was carried out by owner equipment and personnel with waste stripping by a contractor. Initial ore reserves were in predominantly high grade, geologically simple reef structures. A mining method was developed using dozers to selectively mine the ore bearing horizons with a minimum of dilution. As the mine has developed the simple, high grade ore reserves have been progressively replaced by more geologically complex, lower grade reserves. In turn, mining methods have evolved to extract this ore by the most appropriate methods. On-going attention to ore mining practices will ensure that project profitability and viable mine life are optimised.

Jan 1, 1986

The metallurgical works of the Electrolytic Zinc Company is situated on the Derwent Estuary, approximately five miles north of the city of Hobart and near a relatively dense housing area. Zinc concentrates, consisting chiefly of zinc and sulphur, have been roasted at Risdon for 53 years;- recently at rates of 1, 100 tons per day. The zinc content of the ores is converted to zinc calcine (ZnO), which is a dusty material. The calcine is leached with acid to form zinc sulphate, which is then electrolysed to make zinc. The sulphur is oxidised during roasting to sulphur dioxide, part of which is converted to sulphuric acid and part is dissolved in estuarine water which is then discharged to the Derwent Estuary. Photographic slides were exhibited showing the unaffected green flora of the nearby hills, of clear exit stacks, of green lawns, and of a w ll lrcnt nines hnlP anlf nniir.qa within the Wnrka hnnnrla_rv_

Jan 1, 1971

Human resources (HR) practitioners use a general suite of tools that they adopt to suit their company needs and profile. This paper will cover the main areas of a selection and recruitment process from applying for a job, resumT writing, participating in an interview finalising the job offer. A holistic recruitment process has many facets to it. These processes can be quite sophisticated and technical but at the end of the day they are designed to identify talent. A recruitment process will generally include: ability testing (usually online);telephone interview;face to face interview;behaviourally based interviews;psychometric assessments;presentations;simulations (independent or team based); and assessment centres, etc. Understanding the basis of these tools will go a long way to prepare you for the job market, enhance your performance in a recruitment process and stand you out from the pack.

Jan 1, 2008

By D Cioclea, I Toth

Coal mining can lead to the occurrence of spontaneous combustion events. If these events are not prevented they can give rise to fires that have major adverse effects on the mine plan. After studying the chemical structure of coal, the theories of self-ignition and of the oxidation reaction of the organic compounds, two new technologies have been developed for fire prevention based on the inhibition of coal oxidation. The first technology consists of spraying water drops mixed with inhibiting substances into goaves. The second consists of the infusion of a mixture made of several chemical compounds. Tests performed in situ showed the new inhibition technologies to be highly effective even for longwalls mining coal with a high reactivity from the point of view of self-ignition.

Jan 1, 2005

The aim of this paper is to broadly review the purposes of valuations and the methods used to calculate them. Examples are provided by coal and alluvial gold properties. Important factors are consistency, how to deal with uncertainty, and the selection of discount rates. The purposes of valuation are seen as: 1.  valuations for sale; within this category are sales to third parties, sales between partners, and vendor valuations for prospectuses; 2.  to provide bankable estimates for financing; and 3. to provide values for local body rating. The methods used depend on the purpose of the valuation and the amount of information to hand.

Jan 1, 1988

Higher commodity prices and environmental considerations will make selective narrow-vein mining more attractive in future. Unfortunately, hand-held airleg (jackleg) mining is a mature technology that has safety and productivity limitations. Despite decades of attempted innovation, no obvious successor to airleg mining has emerged. A review of some of the possible technologies is followed by a speculative description of the mine of the future, intended to stimulate thinking and discussion during the conference.

Jan 1, 2008

Both blast furnace and steel furnace slags have been used extensively and successfully on main line railroads in the United States for more than 25 years. Annually, these slags are being used as ballast at the rate of about 4 million tonnes of blast furnace slag and 1 mil- lion tonnes of steel furnace slag, much of it on main line with 90 metric tonne car loadings. More steel furnace slag would be used if it was available. Both slags meet all the specification limits of the American Railway Engineering Association. Actual use on high density rail- roads has confirmed the long range economics of their use. Comparison of laboratory tests, such as Los Angeles abrasion, with actual field per- formance has shown conclusively that commonly used laboratory tests can not be used to accu- rately compare the quality of various types of ballast materials.

Jan 1, 1979

By G A. Streltsova

In the paper the main concept of qualitative simulation is determined when computer-aided designing and forecasting of designs of robotised continuous-flow working face complexes for underground mining of hard ores. The parametric model æunderground ore mineÆ and its components û composite models are considered. Frame description of structure of working face complex and methods of organising of rule-oriented representation of knowledge when itÆs operating are given. The architecture of the developed prototype of expert system æworking face complexÆ and construction of a knowledge base for it are described when solving problems of multi-criteria optimisation of computational parameters of the working face complex under conditions of uncertainty. The guidelines for further development of knowledge base and expert system are given.

Jan 1, 2003

By Summers DA

Faculty at the University of Missouri-Rolla have carried out research on the application of high pressure water jets as a means of excavat- ing coal for over 15 years. During the course of this time, a number of different concepts have been explored--the most recent of which has been to use high pressure water jets as a means of extinguishing an underground coal seam fire. This paper will examine the use of some of these technologies and will consider the results as a basis for discussion of further applications of water jets in the future. The structural pro- perties of coal which distinguish it from other adjacent geotechnical material and provide a considerable advantage to water jet cutting, will also be presented and the advantages of using this tool will be discussed.

Jan 1, 1986

By Concha F, Sampaio R

In most of the literature, the hydrocyclone is viewed as a black box in which only global variables are present and where the equations are obtained by curve fitting. Recently some work has appeared where the Navier Stokes equations are solved numerically in the hydrocyclone geometry. However, in all of these works the air core surface, which has an important influence on the hydrocyclone dynamical behaviour, is modelled as being a cylindrical surface of fixed radius. In this work, we model the surface of the air core as a free-boundary which has to satisfy a jump condition, the Young-Laplace equation, relating the physics to the geometry. Based on this model, we are able to explain, qualitatively, some phenomena that have puzzled research workers in the field for many years, and can show, through the air core behaviour, the influence of material parameters on the performance of the hydrocyclone.

Jan 1, 1993

By Burgess J

Present practice of lead-zinc flotation at North Broken Hill Limited is described and factors influencing plant objectives and performance discussed. Mineralogical examination of final flot- ation products showed mineral liberation to be 94T complete and size by size metal recovery tables indicated a need for finer grinding to improve lead and silver recovery, but coarser grinding to improve zinc recovery. A steady grinding circuit, at constant ball mill power and cyclone overflow pulp density, is found desirable for satisfactory flotation circuit operation because instabil- ity in the grinding circuit inevitably leads to flotation instability and as a consequence less than optimal flotation operation. Remov- al of the variable lead flotation middling product from the grinding circuit decreased grinding instability.

Jan 1, 1978

Gentlemen, you heard the good Doctor has commissioned me to make a'summary of the proceedings to date and also to close the said proceedings. It seems that over the years the business of making a summary alternates between'Mr. Pearce and myself, also I,think that w~oever is around onthe day in question 'obtains the task and apparently I drew it this, year. It is hoped you will be patient as previous experience in this capacity'indicates that the best way to proceed is to have a brief summary on each paper and then do a summary of summa~ies. This makes the approacha little cumbersome but it is felt to be fair to each author and it brings'back to the audience some recollections of what transpired at the time and they can make their own decisions, which may not necessarily agree with those of the 'sum'marisor.

Jan 1, 1983

By Jones

Extractive metallurgy in the mining industry in Western Australia has diversified and increased in the last 11 years. Before 1980, the industry mainly produced alumina, nickel, mineral sands and iron ore, with the gold industry restricted to five operating plants using Merrill-Crowe technology. In 1981 Carbon-in-pulp (C]P) plants were commissioned at Kambalda, Kalgoorlie and Meekatharra.Currently, the gold industry has some seventy CIP plants in operation, production of synthetic rutile has increased tenfold to 500 000 tpa, alumina production has doubled and production of copper, lead and zinc concentrates has begun. Other extractive metallurgy plants recover tin, niobium and tantalum, silicon, titanium dioxide and zirconia. Current proposals include vanadium, steel and rare earths.

Jan 1, 1992

Modern minerals projects face serious challenges in earning and maintaining acceptance by their key stakeholders. Factors which underpin effective response to managing these challenges include consideration of public affairs issues from the earliest planning stages, building robust alliances with a range of influential partners, developing a level of transparency in all operations and decision-making and integrating activities towards resolving key strategic issues. Effective community relations is vital and there are a number of elements common to the best approaches. These include senior management support and involvement, appropriate involvement in project decisions and activities by community members and company responsiveness to community expectations. The project's operations manager and executive team must fully commit to developing the capability and processes to meet these challenges. They require a whole of project response and it is not an option to manage them peripherally.

Jan 1, 1997

A Master of Applied Science degree course in Mining Geomechanics commenced in 1983 at The University of New South Wales, taught by extern- al (correspondence) studies. The course is aimed at graduates employed in the mining indust- ry, and especially people involved in geomechan- ics projects on a routine basis in remote locations. This kind of course is unique in Australia and is one of only two correspondence programmes available at this University. The author designed the course and nursed it through the early years, and was Director until 1986. The paper describes the teaching and assess- ment methods and also discusses aspects of admin- istration and coordination of such a course. It is concluded that an important need of the mining industry is being catered for and it appears that similar correspondence course for- mats would also be useful in other areas of the minerals industry.

Jan 1, 1986

Australia had been enjoying a market boom led by the mining sector and West Australian mines were leading the way to satisfy the massive demand for our natural resources, especially from China. However, the Apache gas explosion on Varanus Island, 97 km off the west coast, has clearly demonstrated how the unexpected can suddenly impact on profitability and investor confidence for the mining industry. Risk management with contingency planning can provide the most cost-effective solution to help ensure mining projects are successful. For this discussion we will focus primarily on contingency planning, CP for mining projects à and how to plan for the unexpected. The Apache gas explosion will be our example æUnexpected EventÆ. Insurance may provide financial compensation but it will not protect your reputation as a reliable supplier or prevent damage to investor confidence and future mine projects. However, contingency planning can provide real protection for mining projects à to survive the unexpected.

Jan 1, 2009

The report by Baker (1958, p. 27) of krennerite in contact with gold in a specimen from the 2500 ft level, Phantom South lode, Great Boulder mine, Kalgoorlie, led the writer to look into this further, since Cabri (1965) reported that the assemblage krennerite-gold was unstable between 238° and 356° C, and possibly down to room temperature.Dr. G. Baker very generously provided the writer with two chips from the same rock specimen (No. 14 as labelled from the mine) in which the krennerite gold assemblage was reported to occur. These were examined by polished section and x-ray diffraction techniques and returned to the classified collection of the Mineragraphic Investigations Section of CSIRO.One specimen, showing visible gold, was examined optically with a binocular microscope and telluride material was twice removed from contact with the gold for x-ray diffraction. This material proved to be petzite and so amends a statement by Baker (1958, p. 39) that no petzite was found in the Phantom lodes.The second chip was polished, and microscopic...

Jan 1, 1967

This paper provides an insight into the current status of risk management practices within our industry, based on an industry wide survey, with deliberate cross-reference to quantitative analysis. This survey showed that quantitative assessments appear to be mainly hampered only by the lack of reliable data and industry expertise to carry out such assessments. A short case study will illustrate some of the necessary basic tools and data types that would enable the industry to tap into an additional range of business improvement dimensions to more effectively manage the diverse and changing risk profile of the mining sector.

Jan 1, 2003

In-seam drilling is conducted mainly to drain coal of gas and/or water prior to development or extraction. The requirements of inseam drilling for gas drainage have mainly surpassed the technical limits of rotary drilling and are mainly being addressed by guided down hole motor drilling, albeit at a higher cost. There is an increasing application of in-seam drilling to detect geological structures or other hazards or their absence in advance of mining to reduce the risks of underground mining. Close collaboration between miners, drillers, geologists, researchers and suppliers over the last four years has seen many advances made to improve the accuracy and reliability of inseam drilling. With such developments will come closer control over the ventilation and safety of future mining under deep gassy conditions, but not without costs. The paper summarises the current applications of inseam drilling, recent technological advances and the next generation survey and geophysical sensing tools which are currently being developed

Jan 1, 1998

The mining industry worldwide relies upon the identification of resources that can be economically developed and operated. Access to land is paramount through all stages of the exploration, development, operation and rehabilitation stages. Clear rights to use of land for the purposes of mining must be available and protected throughout the life of the project. Stable and enduring criteria for mining of the resource, once identified, are required to attract exploration and development expenditure. The purpose of this paper is to investigate the varying approaches to granting access to land for use for exploration and mining development, including the processes by which a project is approved by community and government and the time scale for such approval. The paper concentrates on the legal issues arising throughout this process. The law is stated as at September 1997.

Jan 1, 1997