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In April, 1990 the Sydney Water Board invited bids for the construction of the Hazelbrook Carrier Section 3 being part of the Blue Mountains Sewerage Transfer Scheme. In December 1990 the contract was awarded to Costain Resources Limited, Mining Services Division for the sum of $A15.3 M. The works consisted of excavation of 9 520 linear metres of tunnel, 3.35 metres diameter with installation of permanent ground support in the form of rockbolts, mesh, steel sets, shotcrete and in situ concrete

Jan 1, 1993

The mineralised members of the Brockman Iron Formation mined at Mt Whaleback are overlain and underlain by shale horizons. To maximise resource recovery, waste movement within the life of mine plan includes mining of the:unmineralised banded iron formation (BIF), Mt Whaleback Shale, Mt McRae Shale, Mt Sylvia Formation, and parts of the Wittenoom and Jeerinah Formation. With the exception of BIFs, all other units contain zones with varying amounts of sulphides and carbon û æreactive shaleÆ. Reactive shale has a propensity to self-heat and can react with some explosives, resulting in spontaneous explosion. Sulphide rich zones also have the potential to generate acid rock drainage (ARD). Mining reactive shale at the Mt Whaleback mine must be undertaken in a safe, efficient and environmentally responsible manner. Key tasks in the mining process include:100 per cent identification of blastholes that may contain reactive shale; 100 per cent correct loading of blastholes with specified blasting products; 100 per cent of reactive shale mined, hauled and dumped in designated overburden storage areas; 100 per cent containment and treatment of ARD water onsite; and ongoing research into ARD, self-heating and spontaneous combustion. Successful mining of reactive shale requires constant co-ordination between the geology, mine planning, mining and environment departments.

Jan 1, 2002

By D C. Verdon-Kidd, G R. Hancock, M J. Saynor, J B. C Lowry, T J. Coulthard

Designing post-mining landscapes requires quantifying the short and long-term risks. In recent years, computer based landscape evolution models (LEMs) have been used to provide insight into both erosion rates and processes (i.e. sheetwash, rill, gully erosion). An important requirement of these models is high quality model input parameter data, which includes both the surface material (i.e. soil and waste rock) and climate information. However, in many cases such data is limited and in the case of climate information, the data is often short and incomplete. Here we develop climate scenarios and examine different surface material properties using a case study at the ERA Ranger mine located in the Northern Territory, Australia Firstly we develop scenarios that represent the range of future climates that may be experienced at the site. Secondly we develop a series of plausible particle size distributions based on a large sampling exercise of the waste rock material. We then test the sensitivity of different rainfall sequences and surface materials on sediment output using a well-tested landscape evolution and sediment transport model (Hancock et al., 2017). CITATION:Hancock, G R, Verdon-Kidd, D C, Coulthard, T J, Lowry, J B C and Saynor, M J, 2018. Quantifying the effect of climate and surface materials on post-mining landscape erosion – a risk approach using landscape evolution models, in Proceedings Life-of-Mine 2018, pp 122–124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By King R. L

The Bureau of Mines has developed and deployed three expert systems to give advice on mining health and safety. These are: dust control for continuous miners, dust control for longwall shearers, and methane control. All three systems query about the nature and extent of the problem. Typical questions asked deal with observed methane levels, ventilation type and quantity, cutting sequence, and what control technology is employed. Advice given does not focus on a single issue, but may suggest a variety of approaches consistent with the ability of the operator to implement the Suggestions.

Jan 1, 1988

By Scott RM

The project management and construction plans adopted by Davy McKee for the Cooper Basin Liquids Project resulted in a project notable for the Relatively short duration from initiation of the design through to liquids production. Two locations were involved, one at Moomba in the far northeast of South Australia some 800 km from Adelaide, and the other at Port Bonython some 40 km from Whyalla. Total expenditure by the owners at the two sites was in excess of $600 million. Matters covered include organisation, transport, construction, industrial relations, project services and commissioning.

Jan 1, 1986

By W Gale

Rock and coal fractures together with micro seismic vibration is a common occurrence during mining, however, it is very uncommon for coal and rock to be propelled into the roadway. Irrespective, such occurrences do occur and appear to require significantly more energy than is available from strain energy release during coal cutting. The sources of energy which can contribute to the propulsion of coal from the face or ribs are typically strain energy from the surrounding ground, seismic energy from a rapid rupture of the ground in the vicinity, or rapid expansion of gas from within the burst source area. The aim of this presentation is to briefly review the mechanics of a coal burst and to discuss the mining situations for which the energy is sufficient to create bursts. A brief discussion of alleviation strategies is discussed. This is an abstract only. No full paper was prepared for this presentation. CITATION:Gale, W, 2018. An overview of coal burst phenomena, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), p 2 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By R MacGillivray

The Golden Cross mine was an open-pit and underground gold and silver operation from December 1991 to April 1998. Closure of the mine has been based on an approach agreed among stakeholders. The initial phase was the release of a closure plan which was regarded as the blueprint for the following phases and the closure works required to implement the plan. The second phase involved lodgment of consent applications and their granting for the final water management configuration. The final phase is monitoring, confirmation that the site is performing as required by the closure plan and consents and settlement of final ownership, management and surety arrangements. Industry best practice modelling techniques have been used to finalise closure design and have been shown to be good predictors of site water management and discharge performance. Site discharges are in compliance with toxicology based water quality criteria for the protection of aquatic life and most discharges from the site, including those from the closed cyanide-tailings facility, can now be discharged without further active intervention or treatment.

Jan 1, 2002

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 economic future of the Palmer Goldfield lies with both the gold mining and the tourist industries. An equitable solution to the competition between the two involves putting a dollar value on the historical evidence there for our Australian heritage.On 23 October 1986 the Queensland Government gazetted the Palmer River Reserves R16 of 16 200 hectares, in recognition of the competing land uses emerging in the region. The intention is that historically significant gold mining sites and relics will be preserved in situ with provision for continued gold exploration and mining.This paper explores and explains the administrative process of achieving a set of Management Guidelines for Rl6 within the Queensland political milieu. The result of that process is the achievement of some of the highest preservation standards in Australia, prohibiting surface disturbance of defined Category 1 sites, and no mining proposal has yet been refused approval.The Palmer Goldfield R16 experience is a major step in achieving a co-ordinated approach to both current mining and preservation of Queensland's mining heritage.

Jan 1, 1990

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

Dr David Dekker discussed the importance of a multidisciplinary approach to automation, the infrastructure required to support automation, and selecting the equipment for automation. Dekker stressed that automation involves a number of technologies. The mining industry is currently about part-way through the evolutionary process of achieving a fully integrated automation system. He pointed out that the final stages require parallel development of infrastructure such as mine communications. Technologies required for automation Automation systems consist of three parts: the gathering of information, the processing of that information, and taking action.

Jan 1, 1997

By Matveeva TN, Lunin VD, Ivanov VA

The results of theoretical and technological investigations have been presented for the application of electrochemical technology in copper-nickel flotation processing schemes. The sorbed xanthate and dithiophosphate products on chalcopyrite and pyrrhotite have been studied in distinct polarisation conditions of mineral suspensions. Optimum electrochemical pulp treatment parameters have been worked out for copper, nickel, pyrrhotite and other flotation cycles. The method has been examined in pilot plant conditions over a long period of time, technological efficiency has been evaluated corresponding to the industrial flotation process at the Norilsk plant.

Jan 1, 1993

By P Gy

When it comes to sampling theory, a bad sampler is a bad sampler, no matter what, and a sampler is either bad or good. It also is of critical economic importance to tell and understand the difference, especially in a metallurgical plant. In this paper, the grand principles of Sampling Theory are first recalled, then the most popular types of sample cutters for plants are critically reviewed. It is concluded that the industry has a lot of progress to make in that direction, although improvements usually pay for themselves very quickly.

Jan 1, 2002

By F Solomon

This paper explores the recent escalation in public opinion for business to demonstrate the social value it generates through its activities. The concept of social capital is analysed, including the linkages between social and environmental values. Also discussed are the challenges inherent in devising a method for evaluating social value, determining appropriate performance indicators and then evaluating acceptability of outcomes. The linkage between accountability and added social value in the minerals industry is analysed. This includes an illustration of the models of accountability that are now emerging and the adding of social value.

Jan 1, 2000

In recent years rehabilitation of mine sites has become a principal focus of mining legislation in Victoria. In previous eras, managed rehabilitation commenced, if at all, towards the end of mining operations. Planning for rehabilitation works now commences before an exploration licence is granted.The paper gives a brief overview of the requirements for rehabilitation under the Mineral Resources Development Act 1990, Extractive Industries Act 1966, and related environmental planning legislation including rehabilitation bonds and enforcement provisions.A brief review of the current taxation provisions is also included.

Jan 1, 1992

Mining companies often view water quality as an environmental issue. The importance of water quality as a production related issue in mineral beneficiation is greatly underestimated at many mineral processing operations. While most mine sites have comprehensive water balance data for water quantity, the information regarding the quality of water supplies available on site is limited, inadequate or non-existent. The seasonal variations in process water quality and changes in the composition of various water streams are not known. Despite the fact that water represents about 80 to 90 per cent of the volume of mineral pulp processed in a flotation plant, the influence of process water composition on flotation performance is often poorly understood. The process water used at mineral processing operations is made up from a number of available water sources, which can be classified as recycled water streams or make-up waters. The recycled water streams are commonly the tailings and concentrate thickener overflows, filtrate from the concentrate filtration plant and tailings dam return water. Make-up waters can originate from a variety of sources: surface waters (rivers, lakes, reservoirs, dams), groundwater (wells and springs), mains water (potable water), treated and untreated sewage waters and industrial effluents. Mineral processing plants are increasingly recycling water to reduce demand for fresh water and minimise the discharge of wastewater to the environment. However, increasing water recycling can have adverse effects on process water quality and ultimately on the performance of mineral separation processes. The main reasons for reduced plant performance due to water recycling are the accumulation of organic and inorganic compounds in the process water and increased microbiological activities. Other detrimental effects of water recycling can be increased reagent consumption and inefficient dewatering of tailings and concentrates. Recycling of water also tends to accumulate very fine suspended particles. Excessive amounts of slimes in the process water can also have an adverse effect on mineral beneficiation processes. The main constituents of process water are dissolved gases (oxygen, nitrogen, carbon dioxide), colloidal and suspended solids of inorganic and organic nature (including micro-organisms: dead or alive), dissolved organics (natural organic matter, residual reagents, reaction and decomposition by-products of chemical reagents, impurities in the reagents and metabolites originating from microbiological activities) and inorganic compounds (acids, alkalis, inorganic salts, metal ions, anions and heavy metals). Inputs to the chemical composition of process waters are: dissolution of soluble mineral phases present in the ore, surface oxidation followed by dissolution of mineral particles during grinding and mineral processing, the chemical composition of various make-up waters and recycled water streams, and reagent additions during mineral processing. The beneficial or detrimental impact of process water quality on flotation performance can be attributed to a number of subprocesses: adsorption and/or precipitation of inorganic and organic species present in the process water onto the surface of mineral particles, chemical reactions between process water constituents and the chemical species present on the surface of mineral particles and interactions between the chemical and microbiological species present in the process water and the various reagent species added in solution during mineral processing. Dissolved chemical species such as calcium, magnesium, iron, copper, lead, zinc, nickel, sulfates, phosphates and carbonates can have a strong effect on the electrokinetic properties of oxide and sulfide minerals, at certain pH ranges. Several reactions can occur at the solid-liquid interface that can play an important role in determining surface adsorption of reagents. Solid-liquid interfacial properties of mineral particles can be significantly affected by the conformation of adsorbed and precipitated reagent layers, which in turn are determined by solution chemistry. The chemical and microbiological constituents of process water can have a significant effect on liquid-gas interfacial properties and have a strong influence on froth height, strength and stability during flotation. Water chemistry can play an important role in determining the interactions between minerals present in the ore and the chemical reagents added in the mineral processing plant by altering the reagent-solution and mineral-solution equilibria. These interactions can include dissolution, micellisation and precipitation of reagents, dissolution of minerals contained in the ore followed by hydrolysis, complexation, adsorption and precipitation of dissolved chemical species and reactions between dissolved ions and various reagent species present in solution. All of the above mentioned subprocesses can ultimately have a significant effect on the efficiency of mineral processing operations. In this presentation, a systematic approach for assessing the composition of water supplies available at the mine sites and for investigating the influence of process water quality on the efficiency of mineral processing operations will be discussed. The consequences of mixing different quality water streams to produce the required volumes of process water for some flotation plants will be highlighted. To substantiate the water quality issues described in this paper some examples are given from a metalliferous processing perspective. However, the topics described in the paper are not only relevant to metalliferous processing but to all other type of mineral processing operations as well. In fact the principles described in this paper have also been successfully applied to the coal flotation industry.

Jan 1, 2006

By R Lloyd

Coal Services (Health and Safety Trust) funded ARRB Transport Research Ltd to investigate fatigue and performance of truck drivers over consecutive shifts. The main questions were to assess: What is the most important contributor to acute fatigue in mining? Is it length of shift (eg eight hours versus 12 hours) or is it time of day (eg circadian effects)? What is the limit of successive day or night shifts before chronic fatigue affects operator performance in open cut mines? The project methodology included utilising ARRB Fatigue Monitoring Devices (forced-choice stimulus reaction) in eight haul trucks, testing 24 subjects over several weeks. Each subject filled in a Fatigue Risk Questionnaire on lifestyle and health. Operators worked a 14-night, one day off, 13-day roster of 12-hour shifts in a fly-in/fly-out operation with excellent opportunities for restorative sleep between shifts. A total of 3500 hours of real-time data was collected, representing the first set of objective, real-time driver performance data for Australian mining. The data showed that for a single night of driving haul trucks, there appears to be no effect on operator fatigue from the amount of time on task (for the 12 hours). In fact performance was worse through the first eight hours than the last four. The circadian influence had a stronger affect than working more than eight hours. Of the 14 nights worked at the site, nights 13, 14, seven and two respectively, were the worst. This presents a conundrum for policy makers who may like to place caps on working hours or rosters in the hope that it will alleviate the fatigue issue. It will not. The major finding within this study is the combined influence of circadian rhythms (human body clock) and individual variability on performance. The lifestyle habits and the health of individuals have a profound effect on operator performance as shown by the strong positive correlation between high fatigue risk scores from the Fatigue Risk Questionnaire and poor performance. An individualistic approach would appear to have the best chance of reducing high potential incidents due to fatigue through successive nightshifts.

Jan 1, 2005

By Cerutty L

To those who have been engaged in the construction of mining and metallurgical plants during the war and post-war periods, it is quite unnecessary to point out the large increases and violent fluctuations in prices of basic commodities and the steady and persistent rise in labour costs. It may, however, be of interest to present these facts in graphic form, and survey the relative heights of the various maxima and the lead and lag of individual waves. Since Descartes demonstrated for us moderns the analogy between geometric form and algebraic statements, the two-dimensional graph has found widespread application. Mathematicians have developed for our information, if not for our confusion, the triangular diagram and the solid three-dimensional figures, which have proved so useful, at least in the hands of the metallurgists at Port Pirie. The model (Plate 1.) which is exhibited here does not pretend however, to indicate the connection between any three inter-related variables, and it is not proposed to burden members with any abstruse mathematical expression for the irregular surface of the blocks. While time is an ordinate common to all sections of the model, each illustrates separately the variation in cost of some particular quantity between the years 1914 and 1922. It is an easy matter to record such individual variations, but it would be an impossible task to state any equation describing accurately the dependence ot the prices, say, of hardwood or of galvanized iron upon that of labour at any particular point of time. The cost of living curve, which has attained such prominence, if not notoriety, in the last few years, is the result of an attempt to show the mass-effect of the components. It is the difficulty found in "assigning the correct weight to the separate items which makes the aggregate curve somewhat misleading at times.Turning to the model, it will be noticed that each section consists of half a dozen pegs.. The first in each row,that coloured red, represents the cost of some particular quantity, such as bricks, timber or coal, at Broken Hill in 1914. The next peg, that coloured blue, represents proportionately prices for that quantity in Hobart during...

Jan 1, 1922

By J W. Harris

There are numerous detrital diamond deposits worldwide with uncertain or disputed links to known primary kimberlite/lamproite sources. In this study, we utilise 40Ar/39Ar dating of clinopyroxene inclusions in diamonds as a provenance tool applied to the mega-placer deposits along the West Coast of southern Africa. These data demonstrate that most West Coast diamonds originated known Cretaceous kimberlites on the Kaapvaal craton with negligible input from proximal Permian glacial deposits. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Away from past controversial presentations, a matter of fact, intuitive and simplified approach to the Theory of Sampling (TOS) sampling variance prediction formula is offered which gives an insight on the type of model required for the liberation factor, the practical limitations of such model and methodological principles for its calibration. This paper intends to see what happens in TOS when trying to go from the very simple towards the full level of real life complexity, and actually tries to answer the question: Is there such a thing as a æsimpleÆ TOS?

Jan 1, 2005