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A real Dorothy Dix title has been selec- ted for this paper. It has the advantage, however, of being capable of being interpreted in many different ways and hence I can select my own approach. You probably are thinking that this topic would be more appropriately handled by an Accountant. I wish to make it clear at the outset that I am not skilled in the sometimes mysterious ways of Accountants - likewise that profession frequently has difficulty in pinning down economists. We have our own strange ideas about profits, marginal efficiencies, cost/benefit analysis etc. What follows is in the main a mixture of two disciplines, probably in a form that few of the purists from either side would accept. Nor do I expect the reader to accept my own prejudices. The paper is designed to stimulate thought and discussion'on the subject. Emotive words such as "profit" and "loss" make for wide differences of opinion. At the time of writing there is a surprising degree of acceptance of the viewpoint that profits in Australia are too low and one is tempted to make this point of near agreement a starting Point.

Jan 1, 1975

By Thomas R

The successful `marriage' between a company seeking to raise funds to develop a project and their financiers calls for a strong mutual understanding of each other's needs. For a company attempting to raise funding, the alternative methods are ever expanding. The optimum method will vary depending on the financial position, risk/reward outlook of the company and the strength of the project for which development capital is being sought. It is likely that small mining companies will need to raise equity funds for advancing projects to the development stage. At that time, they will probably still require a reasonable level of shareholder equity to meet the requirements of banks and other parties to cover potential cost over-runs on the project and feasibility costs. Larger companies, however, are likely to find it much easier and cheaper to raise debt from banks. When evaluating companies and projects for funding, banks will pay particular attention to the quality and experience of management in developing similar projects and it may be necessary for some companies to retain the services of outside consultants. Before a project needs funding, companies should meet with potential financiers to develop relationships to select and ensure a smooth transaction to funding in the future.

Jan 1, 1997

Key incompatible element ratios for metabasalts from the Early Permian Croisilles and Patuki Volcanics, South Island, New Zealand, provide constraints on the tectonic environment in which their precursor ophiolitic protolith formed. Two geochemically distinct metabasalt suites are recognised among both the Croisilles and Patuki rocks. Metabasalts from one suite exhibit the geochemical signatures of depleted tholeiites from oceanic spreading ridges (N-type MORB) or spreading centres in evolved back-arc basins. These N-type tholeiites show high Zr/Nb ratios (Zr/Nb = 37-62) and are depleted in light rare earth elements (LREE)((La/Y)N

Jan 1, 1987

Feasibility studies in the development of mining projects are fundamental to most investment decisions. It is important that the issues addressed and the degree of detail involved in feasibility studies are consistent with the investment decisions to be taken. Emphasis should be placed on a thorough analysis of critical project parameters prior to detailed investigations being undertaken into other activities which are not relevant to the decisions at hand. Therefore, the issues to be decided upon should be influenced significantly by the stage of development of the project and by the reliability of technical and financial information used in the study. Some of the more critical parameters of feasibility studies are commodity prices, inflation rates and discount rates. Advice is given on the selection of these inputs and also on their application in the feasibility study as the project progresses through its various development stages. The feasibility study should involve not only a formal evaluation of project economics but also an analysis of all project related risks and a comparative analysis of projects competing in

Jan 1, 1983

Portable crushing at Duval Corporation's Sierrita open pit mine has proven both the economics and operability of large, hardrock, portable systems. In-house expertise was utilized to create a system incorporating both operational and maintenance features requested by operating personnel. The monitor/control system involves over 400 channels of information and is based on a DEC 1SI 11/2 microprocessor communicating with seven microprocessor-based data acquisition systems over a 4-wire, multidrop link. The year and one-half successful operation affirms the design philosophy and the hardware/software implementation.

Jan 1, 1985

The new generation Hlsmelt« Direct Iron Ore Smelting Process is a CRA Limited technology initiative. The process development is now focussed on commercialisation. The goal is to have the first commercial vessel operating around the year 2000. The HIsmelt« Process, based on the abundantly available iron ore fines and the more readily available non-coking coals, has the potential to fundamentally change iron ore processing through the application of high intensity techniques to replace the current sinter/coke ovens/blast furnace .technologies. The process will have great potential in the rapidly growing economies of Asia where steelmaking aspirations are based around local market focussed plants. This potential can be. realised as a supplier of premium grade iron units to electric arc furnace (EAF) steelmaking plants or as the front end to an ore based steel mill.

Jan 1, 1996

Modern off-highway trucks have evolved over 30 years from small 20 ton units to vehic- les with capacities of up to 170 tons. Diesel engines are used by all manufacturers while transmissions are either mechanical or electri- cal. Development over the years has kept pace with component availability from engine, trans- mission and tyre manufacturers.Computer simula- tion studies are recognised for purposes of vehicle evaluation and costing under various op- erating conditions. Several manufacturers are currently manufacturing or evaluating vehicles with capacities of up to 260 tons. This paper describes the essential facts associated with the operation of off-highway trucks of the rear dump type in the mining industry.

Jan 1, 1973

By Granholm S

The current emphasis within the mining industry to reduce the cost of production has stimulated interest in the fields of maintenance and operational reliability of capital intensive mining equipment. From an economic point of view, high reliability is desirable to reduce the maintenance costs of the systems. Two graphical methods consider reliability analysis. The first one, the method of Total Time on Test (177)-plotting deals with the reliability data which are free from trend and serial correlation. The second method which is based on time dependent modelling approach deals with the data which are not free from trends and serial correlation. The examples show how these graphical methods can be used to calculate the optimal maintenance intervals for components or systems.

Jan 1, 1991

Author Biography William Poole was born in Sydney, NSW in August 1868. He was educated at Sydney Grammar School. William spent two and a half years as a cadet in the Railway Construction Branch of the NSW Department of Public Works doing office and field work. He then undertook a civil engineering course at Sydney University. Following this he was employed for six years as assistant and resident engineer at the Water Conservation Branch, NSW and was in responsible charge of various field operations, surveys, river gaugings and works of constructions including a large timber weir and also a concrete weir on the Macquarie River, NSW. He then undertook a mining and metallurgical course at Sydney University and became a graduate (BE) with honours in civil engineering, mining engineering and metallurgy. He then spent four and a half years with BHP Co, one and a half years at Broken Hill in the mining and concentration works and three years at the smelting works in Port Pirie, SA, in the latter case he was metallurgist and night superintendent and during that time had responsibility and control at night of the blast furnaces and, during the last 15 months, of the whole of these large works. The author left the Port Pirie, SA works to assume the position of Director of the State School of Mines at Charters Towers and had responsible control of the establishment and also lectured in mining, surveying and structure. William Poole was honoured to hold membership in the following organisations: Assoc M Inst C E, L S of NSW, M Aus Inst M M, Assoc Inst M & M (London).

Jan 1, 2006

By Jimbo I, Ogawa O

A series of experiments was carried out to investigate the solubilities of copper, arsenic, antimony and bismuth in silica-saturated iron silicate slags under controlled oxygen partial pressures at 1200 and 1250¦C. Molten copper containing each of the above elements was kept in contact with a slag in a silica crucible for 24 or 48 hours to attain equilibrium. No me- chanical entrapment of metal into the slag was observed. The appearance of the magnetite phase in the slag was avoided by holding oxygen potentials at substantially lower values than that evaluated from available data on iron silicate slags. Solubilities of copper, arsenic, antimony and bismuth in slags were plotted against oxy- gen potentials and both oxidic and atomic types of dissolution were found, except in the case of arsenic, from the dependencies of the solubili- ties on the oxygen potential and from positive intercepts of regression lines when extra- polated to zero oxygen potential. The dissolu- tion of arsenic seemed mostly oxidic. Distri- bution coefficients of arseò,ic, antimony and bismuth between copper and slag are also Discussed.

Jan 1, 1980

By P J. Hansen, D G. Franklin, M E. Trim, J V. Myers

The Northern Sewerage Project (NSP) is an upgrade to one of MelbourneÆs ageing, under-capacity trunk sewers. It will reduce the volume and frequency of wet-weather overflows to the Merri and Moonee Ponds Creeks and facilitate new housing developments in the northern suburbs of the city. A total of 12.4 km of tunnel and eight vertical access shafts will be excavated as part of the two project stages: Stage 1 (NSP1) will be owned and operated by Melbourne Water (MW) and Stage 2 (NSP2) will be owned and operated by Yarra Valley Water (YVW). The owners require the project to have a service life of 100 years, a requirement significantly beyond many of the current Australian Standards, which aim to achieve service lives greater than 60 years but are typically assumed to achieve 40 to 60 years. Because of the potentially corrosive natures of the external environment along the tunnels and the internal sewer environment, durability was a key concern for NSP1 and NSP2. Stringent specifications were applicable to the tunnel lining systems. This paper describes the corrosive environments impacting NSP1 and NSP2, explains the key design differences between the two stages and details the lining systems considered and selected to achieve the clientsÆ desired 100-year service life. The project design is complete and construction began in 2007.

Jan 1, 2008

By Simes C. D

Results of experiments for dissolution of zinc by aeration of sphalerite in glass, copper, galvanised iron and stainless steel vessels of identical dimensions are reported. It was found that in a glass container dissolution of zinc reaches a maximum after 30 min aeration and then decreases whereas in the copper container dissolution remains nearly unchanged up to 30 min aeration and then increases. In the cases of galvanised iron and stainless steel containers zinc dissolution increased steadily with time up to 60 min aeration. It is suggested that the different rates of dissolution in glass and copper containers may be due to electro-chemical actions.

Jan 1, 1984

By U Berg, T Neumann, Y Song

Eutrophication of water bodies is one of the most severe environmental problems worldwide. It is well known that the availability of phosphate, as the limiting nutrient, is crucial for increased primary production and eutrophication. Calcite exhibits positive surface charge in most natural waters and can therefore be used for phosphate immobilisation. In this study, sorption experiments were performed in order to test different calcite materials regarding their suitability for use in restoration of eutrophic lakes. These short-term experiments were performed under different hydrochemical conditions (pH, SICC, initial dissolved P concentration) and with varying calcite properties (specific surface area and amount) in order to predict the long-term stability of the Ca-P-bonds. Peculiar shapes of isotherms that could not be explained only by adsorption processes were detected in the individual experiments. Depending on the residual P-concentration in solution, the isotherms can be divided into three sections indicating different processes responsible for the P-fixation on calcite surfaces. Adsorption prevails in equilibrium with lowest residual P-concentrations. The inflection of the isotherm at moderate residual P-concentrations suggests that precipitation and transformation of a Ca-P compound becomes dominant. This is supported by characteristic Ca/P-ratios for different Ca-P-compounds (b-tri- calcium-phosphate, octa-calcium-phosphate). On the new surface, phosphate ions again are fixed by adsorption. The observed transformation of P-bonding is crucial for sustainable phosphate immobilisation on calcite surfaces. While pure adsorption processes are reversible, the development of a thermodynamically stable Ca-P-phase, like hydroxylapatite, will lead to a lasting immobilisation of phosphate.

Jan 1, 2008

A key premise to this paper is that most people involved in the design and implementation of drilling and blasting operations could benefit from a greater understanding of the geological materials, deposits and landforms they are dealing with. The second key ingredient for successful blasting is the concept of blasting objective. Mine operators and blasting contractors must be clear on what drives their costs (blasting leverage) and should formulate blasting objectives and operational targets which help in this regard. Many operators ignore geology descriptors and features apart from the name of the rock and start crudely quantifying the rock mass properties in terms of uniaxial compressive strength, or even worse still as hard or soft. This occurs too early in the design process and not much attention is paid to the geological materials, geological structures and the characteristics of the deposit they intend to excavate. In effect the rock type name and the strength descriptor become the site geology. Furthermore many blasting operators do not formalise their blasting objective, do not set operational targets and do not measure results to the degree required for continuous improvement. In this paper a number of civil, surface mine and underground mine blasting applications are tabulated in terms of typical blasting objectives and common geological materials. A good description of geological materials can convey a lot of useful information for blasting operators if they are able to accommodate this knowledge. In addition a clear statement of the blasting objective and associated operational targets will maximise the likelihood of achieving blast-driven downstream productivity improvements. The æStarting at Both EndsÆ combination is deemed extremely useful for any continuous improvement blasting program.

Jan 1, 1999

The New South Wales Department of Mineral Resources has, since 1974, administered the Derelict Mines Rehabilitation Program (DMRP) to reduce the environmental impacts of abandoned and orphan mine sites. The application of the DMRP is presented in case studies of sites from the South Maitland Coalfield featuring residual drainage of acidic and saline water in a semi urban and rural community setting. The acidity here is typically derived from iron oxidation in shallow underground coal mine workings and in surface emplacements of coal washery reject materials. This paper presents summary information on AMD investigation, monitoring and rehabilitation. The experiences of community expectation, stakeholder consultation and peer review are discussed.

Jan 1, 2003

By S Marsters

Imerys Tableware New Zealand Limited has mining rights to four deposits of halloysite, which are located about 203 km north of Auckland, New Zealand. These primary deposits were formed by the hydrothermal alteration and weathering of rhyolite domes. Halloysite clay is currently being mined from two of these deposits and then processed for export markets. From humble beginnings in the mid 1950s, the Northland halloysite was processed initially for paper filler markets and then for higher value tableware and technical ceramic niche export markets. The paper will briefly cover the geology and processing of halloysite and then examine the history of New Zealand China Clays Limited, now Imerys Tableware New Zealand Limited and then look to its future as part of global industrial minerals company, Imerys.

Jan 1, 2002

By G L. Simmons, K M. LeVier, R Kappes

The low potential hydrophobic state of pyrite in amyl xanthate (PAX) flotation with nitrogen is of particular interest with regard to the N2TEC flotation technology currently being used for the recovery of auriferous pyrite at NewmontÆs Lone Tree Plant in Nevada. Initially, the N2TEC system had been found to operate satisfactorily, but cyanide in the flotation mill water appeared to be responsible for a loss in pyrite recovery. This supposition was confirmed with laboratory experiments, and a program was initiated to study flotation chemistry variables by electrochemically controlled contact angle measurements. Experimental results show that activation of pyrite in such cyanide solutions can be achieved more effectively with lead than with copper. Subsequently, based on these fundamental studies, significant improvement at the Lone Tree Plant was achieved by lead activation, in which case the recovery increased to expected levels. The effect of activator is particularly significant not only with respect to pyrite depression by residual cyanide, but also with respect to collector (PAX) consumption and the initial state of the pyrite surface. Experimental results show the importance of the pyrite surface state and the rather interesting features of the activation process.

Jan 1, 2005

By Henderson J, Ward RG

Dissolved oxygen has been measured directly using a rugged, reliable, accurate electrochemical probe system developed for steelworks application by B.H.P. Central Research Laboratories. Furnace measurements show that the steel is generally supersaturated with oxygen and that oxygen contents vary considerably from heat. to heat. Ladle measurements also show considerable heat-to-heat variations. Analysis in terms of ladle deoxidation chemistry differentiates between carbon monoxide controlled and manganese silicate controlled oxygen levels. Deviations from these levels are sometimes due to aluminium present in other added ladle alloys but in some cases the plant applicability of laboratory derived equilibria is questionable.

Jan 1, 1972

By S Vink, V Nanjappa, C J. Moran

Poor quality water resulting from interaction of surface run-off with saline mine spoil and soils can cause significant problems for water reuse on mine sites. Not only can this saline water lead to machine corrosion and increased maintenance costs, but may cause detrimental effects on the environment. Determining the geochemistry of mine spoil, and the likelihood of salt dissolution during rainfall events, may aid in more effective mine site management of water. Spoil samples were taken from three areas of the German Creek mine site, situated in the Bowen Basin coalfield, Queensland. Samples from two undisturbed areas on the lease were also collected for comparison. Analyses were performed using a variety of laboratory techniques: leaching tests, effective cation exchange capacity determination, X-ray diffraction, clay quantification, and total organic content determination. Results show that dissolution of surface (top 2 cm) salt minerals from spoil areas is an important contributor to surface run-off salinity during rainfall events. Equally, ion exchange with clay minerals appears to be a significant source of elevated ion concentrations in run-off waters. Findings from the undisturbed areas show undetectable quantities of salt mineral species, resulting in waters with low ion concentrations. More generally, monovalent cations (sodium, and to a lesser extent potassium) appear to be derived from dissolution of salt precipitated whereas divalent cations (calcium, magnesium) are more likely to be sourced from exchange reactions with clay minerals. Incorporating knowledge about the mechanism of cation mobilisation from spoil with the spatial distribution of spoil properties and understanding of the dynamics of water quality variations on the site will aid in development of integrated water quantity and quality management strategies.

Jan 1, 2009

Deep hydrothermal fluids adjacent to the Alpine Fault move through the brittle-ductile transition to mix with convecting fluids from near surface environments. These tectonically driven fluids evolve mainly from prograde metamorphism at mid crustal depth (ten kilometres) within the ductile regime which has been elevated due to advection and drag on the fault plane. Through the onset of brittle failure and cataclasis within Alpine Fault mylonites, fluid overpressuring results in hydrofracturing and localized implosion. Along the length of the Alpine Fault, hydrothermal alteration varies on most levels (Table 1). There is an observable increase in Fe-Mg carbonate between the Waitaha and Taramakau Rivers (between Ross and Aurthur's Pass, respectively). Field studies concentrate to the north east of the Arahura River, noted for historical mineral wealth. Late meteoric fluids move through cataclasite, brecciated mylonite, and other open fractures. Chloritisation is the major retrogressive phase. Dolomitic hydrofracture veins (Figure 1) within coherent mylonites contain iron and copper sulphides. Notably, the enrichment in Fe-Mg carbonate towards the Alpine-Hope Fault intersection seems to represent a region of enhanced permeability possibly related to shallow seismicity, increased regional faulting, footwall variation, strike-slip dip-slip distribution, and/or topographical anomalies (ie saddles). Isotope studies identifying an 'Inboard Fault Gouge Calcite Zone' correlate to values from the Main Divide region at the headwaters of the Arahura River (Browning Pass-Wilberforce Valley) (Becker et aI, 2000). These correlations are supported by rare arsenic anomalies (avg l06 ppm n = 5, Figure 2) found in both regions which suggest that fluids may be interconnected at depth.

Jan 1, 2001