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By G A Brown

Environmental legislation is changing rapidly throughout Australia at the present time, and with that change comes additional responsibilities for the mining and petroleum industries. Among the many changes that are being made are increased penalties for both criminal and accidental environmental impairment. The defences for criminal offences are limited and for other offences the laws may impose strict liability - in effect the offender is guilty until proven innocent. Mines may be included under contaminated land legislation, creating additional liabilities for clean-up, rehabilitation and long-term management. It is not unknown in Australia for the value of a mortgaged property to be less than the amount of the environmental liability acquired by a mortgagor in possession due to contamination of the site. An essential part of the management program for resource projects is now the regular conduct of an environmental audit, the results of which assist in the management of the legal and financial liabilities facing company directors and managers. The audit can also assist with negotiations with government agencies, staff, unions, insurers, Aboriginal and other community groups. An environmental audit may also help to ensure that companies are claiming the maximum allowable deductions for environmental works under the tax laws, and provide evidence in support of such claims. Environmental legislation affecting resource industries Environmental legislation in Australia is changing rapidly and can impose massive constraints, substantial administrative costs, and considerable liability on directors, managers and the corporation. Pollution control legislation Every State and Territory of Australia has a range of pollution control legislation contained in either individual acts relating to air, water, noise and land, or embodied in a single environment protection act. Pollution control legislation provides a critical management baseline for resource industries throughout Australia, often requiring the full-time attention of an environmental manager or an environmental department. In general, it is an offence to discharge effluents into water, or emit gases into the atmosphere above prescribed limits, cause noise above a regulated level, or contaminate land without a licence. A licence determines how much of a substance can be discharged, the location, the receiving environment, the quality, and the time at which discharges can be made or noise can be caused. Planning legislation Planning legislation controls where a project is located, how it will be constructed and operated, how large it is allowed to be, and what will happen once the project is completed. Development consents or approvals will generally contain a range of conditions controlling the preparation of the site, the construction of the facility and the way it is operated throughout its expected life time. Resource projects may be regarded under legislation as scheduled or designated developments requiring special treatment during the decision-making process. Under planning legislation, it is usual for resource projects to be subject to an environmental impact assessment process. Resource legislation Resource legislation specifically covering mining and petroleum in Australia, also contains requirements regarding protection of the environment during exploration for and extraction of minerals and oil. A mining or petroleum production lease usually contains numerous conditions regarding protection of the environment and rehabilitation of the site during and after the life of the extractive process.

Jan 1, 1994

Electronic Detonators have made significant strides over the last few years, both in quality of product and performance in different blast applications. The precision and flexibility of the SMARTDET units provides the mines with a powerful means of controlling blast results, giving both cost and productivity improvements. The SMARTDET Electronic Detonator System, robust and easy to use, has been successfully deployed over the last 18 months in improving mine productivity and creating safer working conditions in both quarrying and long-hole stoping. The key to the improvements has been the precision and flexibility of the electronic timing, and the ability of the mine personnel to grasp the concept quickly and use it effectively.

Jan 1, 1999

By M Simanjuntak, A M. Supomo

PT Freeport IndonesiaÆs copper/gold operation disposes of approximately 222 000 dry metric tonnes of tailings per day via two thickeners. Reduction of the flocculant dosage rates in each of the tailing thickeners has been achieved with the installation of Clarometers«, modifications to the existing operating DCS control strategy and a change in plant flocculant. This has reduced the flocculant consumption rate in the last twelve months by approximately 20 per cent. It has also highlighted the disparity in the settling rates of the two thickeners. Collaborative efforts between Cytec technical site engineers and Freeport operational personnel have made possible the overall gains achieved in the tailings thickener optimisation.

Jan 1, 2003

By Carthew SJ

The early period of South Australia's mining history was dominated by Cornishmen as large numbers of miners and their families migrated to escape closure of the Cornish copper mines. Records show that Carthew families migrated from Kent and Cornwall to South Australia. Those from Redruth, Cornwall, were miners and their family history provides an insight into the condi- tions under which early miners lived and worked. Carthews are one of the oldest surviving mining families in South Australia and their movement pattern has been typical of many other early Cor- nish mining families.

Jan 1, 1987

By K Voigt, B Bolton, C Rumble

The Ok Tedi copper and gold mine is owned and operated by Ok Tedi Mining Limited (OTML) and is located in the Star Mountains of the Western Province of Papua New Guinea. Waste materials (both sulfidic and carbonate materials) from mining operations, comprising 55 Mt of waste rock and 31 Mt of tailings per annum, are discharged into the headwaters of mine area creeks where erosion and sediment transport carries significant proportions of the total waste into the Ok Tedi and Fly River systems. The tailings are potentially acid forming (PAF) while the waste rock has been strongly acid consuming with an excess of acid neutralising capacity (ANC) due to the high proportion of limestone waste. Tailings and waste rock are eroded into the river system and transported to the lower Ok Tedi and floodplains where deposition takes place. Because of concern due to vegetation die back, a dredging operation commenced in March 1998 to remove the sand fraction from the main river channel. OTML identified a potential future ARD risk from the stockpiled sands due to reduce limestone production at the mine and sulfide/carbonate mineral segregation in the river system and in the dredge sand stockpiles. This paper describes the structure and framework of an empirical model developed to assist OTML in planning ongoing mining operations to control ARD. Modelling identified the need to provide additional mined limestone to prevent future ARD generation from material deposited in the mine area creeks. With the additional limestone, the ARD risk in waste rock storage areas and in the Ok Tedi and Fly River sediments is predicted to remain low due to the combined effects of high ANC, high alkalinity of natural waters and high moisture contents (mostly fully water saturated). However, monitoring and modelling indicate that the ARD risk from the stockpiled sands will increase substantially during the remaining years of the operation. OTML have initiated programs to identify and evaluate options to mitigate this risk.

Jan 1, 2003

By P N. Nkrumah, A van der Ent, G Echevarria, P D. Erskine

Nickel phytomining is a low cost alternative to traditional nickel mining and a complementary process to existing mining operations in areas with low-grade nickel soils or nickel waste material. The process of nickel phytomining consists of growing selected hyperaccumulator plant species (‘metal crops’) on Ni-rich (ultramafic) soils, followed by harvesting and incineration of the biomass to produce a ‘bio-ore’ from which Ni salts or Ni metal may be recovered (Chaney et al, 2007). The ‘metal crops’ are selected on the basis of high biomass yield combined with high Ni concentrations (>1 per cent) in the above-ground biomass (Chaney et al, 2007). Currently, Alyssum murale and A. corsicum have been used for Ni phytomining trials, mainly undertaken in Albania and USA (Bani et al, 2015; Li et al, 2003), while the agronomy of <10 species has been tested in temperate regions (Nkrumah et al, 2016). Nickel phytomining has high economic potential; however, large-scale demonstrations are needed to provide ‘real-life’ evidence for commercial operations (van der Ent et al, 2015). Unrealised opportunities exist in tropical regions for commercial scale Ni phytomining. To date, the agronomy of tropical ‘metal crops’ has not been tested. This extended abstract presents the progress of tropical phytomining, and reports on agronomic trials undertaken to determine whether the trends in temperate regions could be confirmed in a wet tropical environment.CITATION:Nkrumah, P N, Erskine, P D, Echevarria, G and van der Ent, A, 2016. Progress in tropical nickel phytomining, in Proceedings Life-of-Mine 2016 Conference, pp 135–137 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By P D. Erskine, A Hine

The current Queensland Government’s rehabilitation guidelines for post-mining landforms present a hierarchy of preferred outcomes for different areas within the mine site (see Figure 1). Within all areas, restoration of a ‘natural’ ecosystem is clearly prioritised as the preferred end land use, although it is not a mandatory practice. Beyond the official guidelines, there is also an implied preference for renaturalisation echoed in most environmental impact assessments and closure plans (Lamb, Erskine and Fletcher, 2015). In practice, however, ecosystem restoration does not extend to construction of a realistic topographic form, largely rejecting the ‘natural’ aesthetic implied by ecosystem restoration in favour of adopting a functional aesthetic in deference to standard engineering criteria.This presentation argues that the established disconnection between actual and implied landform aesthetics is indicative of a wider problem around end landform planning. It contends that such disconnects are the result of the impact of competing ‘ways of seeing’ (Bradley and Kearney, 2007) the same landscape, and reflect the struggle between, and inclusion of, these differing perspectives within the planning process itself. We propose that recognition of the complexity of landscape perceptions is key to improving post-mining landscape outcomes, and the misalignment between land use values and landscape aesthetics can be addressed by establishing an overarching framework for landscape preferences. As such, we outline the reality of stakeholder landscape preferences, and present a critical response to current planning practices within the life-of-mine (LOM).CITATION:Hine, A and Erskine, P, 2016. Recognising and integrating stakeholder landform expectations into life-of-mine planning, in Proceedings Life-of-Mine 2016 Conference, pp 154–157 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Korsch RJ

Permian oroclines in eastern Australia must have formed by sliding on a detachment surface. It is identified as a westward- dipping Devonian and Carboniferous sub- duction zone. Major strike-slip faults probably sole out on the same surface. One major fault with an associated serpentinite belt was pulled away from the craton abd bent into loops. Basins formed in the loops.

Jan 1, 1987

Background A recent development in many industries,' including the mining industry, has been ever increasing acceptance and adoption of extended (12-hour) shifts and compressed work cycles compensated by more time off work by employees between cycles. In the Western Australian mining industry development of `long-distance-commute' (LDC) coincided with adoption of 12-hour rotating shifts. Preludes to LDC were the `construction-style' rosters with two crews plus allowance for annual and sick leave relievers working the statutory 13 consecutive shifts followed by one shift off. Crews rotated day to night shift weekly or at fortnightly intervals. Average hours of 72 to 78 per week were common. The author had personal experience working these rosters in the East Pilbara of Western Australia from 1977 to 1982. Workers tolerated these rosters until a suitable combination of frustration, boredom, despair and the `Five Grand Fever' triggered them to `pull the pin' and head for relaxation in Bangkok, Manila, Nimbin, or Margaret River according to their personal tastes.

Jan 1, 1996

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

By Mining Geophysics

Modern geostatistics has eliminated much of the guess-work in ore reserve estimation, and can calculate levels of confidence for the reserve estimate. Geological modelling software has brought about a revolution in the communication of complex geo-variables to mining engineers, metallurgists, surveyors and managers. Mine planning and scheduling can now avail itself of a veritable toolbox of enabling technologies.

Jan 1, 1994

By S Nowosad, A Binder, O Langefeld, M Bothe-Fiekert, F Apollo

The mining industry faces complex and urgent challenges driven by an increasing demand for raw materials, and a socially demanding globalised world. The extraction of primary raw materials is today more important than ever as one of the cornerstones towards a sustainable future since the increasing demand for the raw materials required for the energy transition. In the last three years, leading countries as USA, China, Canada, Australia, and the European Union (EU) have developed and adopted strategies to enhance domestic extraction capabilities, diversifying sources, fostering innovation in recycling, and promoting international collaboration related to critical raw materials. On 2022, the Inflation Reduction Act was signed into law in the USA, in June 2023, the Australian Critical Minerals Strategy 2023–2030 was published and in March 2024, the Council of the EU adopted the European Critical Raw Materials Act. On the other hand, raw materials extraction is facing higher environmental and safety standards and regulations, as well as scrutiny from the broader public. Regrettable environmental accidents as tailing dam failures or acid mine drainage occurrences have led to a general distrust of mining activities leaving mining companies with the dual imperative of increasing output while implementing sustainability, decarbonisation, and circularity as a core value in their production processes. This challenging environment offers the opportunity to enhance ‘blue mining’ (BM) as a sustainable holistic approach that integrates the principles needed to plan sustainable, reliable, and responsible mines for today’s and future generations by implementing the principles of circular economy (CE). This requires a fundamental shift from the traditional linear economy approach to a sustainable, circular economy strategy. At its essence, BM encapsulates four crucial aspects – energy, ergonomics, water, and circularity and integrates these four aspects into integrative mine planning, defining clear goals and objectives from the ‘blueprint’ of a mine towards a beneficial post-mining activity. Its implementation can lead to maximisation of resources beyond the life of the extractive mine and sustainable use of materials by integrating the principles of circular economy and multiuse mine, see Figure 1. These concepts complement and recognise the need to minimise environmental and social impacts while advancing economic development. Finally, this contribution explains the requirements and challenges of moving from linear to dynamic planning approaches under the BM concept. This way, BM stands as an approach that can contribute to the mining industry receiving necessary approvals and support from society leading to a long-term transformation of the industry’s image.

Sep 1, 2024

By J A Evans

A well-maintained and low cost mining operation today requires the use of condition monitoring techniques. At ERA - Ranger Mine oil analysis, vibration monitoring, infra-red themtography, and performance analysis have been successfully applied over the last four years to lower operating and maintenance costs. All condition monitoring is scheduled through a comprehensive in-house developed maintenance management system known as the Engineering Information System (EIS). (EIS) is used extensively at Ranger to ensure consistent frequency and recording .of all condition monitoring data. This paper provides an insight into the benefits of condition monitoring and explores the future direction for condition monitoring techniques at Ranger.

Jan 1, 1994

Spectacular high-temperature hot springs (æblack smokersÆ) on the deep ocean floor are producing economic concentrations of base and precious metals. Mining these seafloor massive sulfide (SMS) deposits is about to become a reality in 2010, subject to the timely issuance of permits. Three Australia-based private companies and two government agencies inJapan and Korea have exploration licenses or applications covering vast areas of the seabed in the western Pacific targeting SMS deposits. Technological and financial challenges for recovery of seafloor sulfide deposits are being met and mining these may be less environmentally deleterious than mining on land. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By M Balamurali

In mining, grade control generally focuses on blasthole sampling and the estimation of ore control block models with little or no attention given to how the materials are being excavated from the ground. In the process of loading trucks, the underlying variability of the individual bucket load will determine the variability of truck payload. Hence, accurate material movement demands a good knowledge of the excavation process and the buckets’ interaction with the environment. However, equipment frequently goes into off-nominal states due to unexpected delays, disturbances or faults. The large amount of such disturbances causes information loss that reduces the statistical power and biases estimates, leading to increased uncertainty in the production. A reliable method that inferences the missing knowledge about the interaction between the machine and the environment from the available data sources, is vital to accurately model the material movement. In this study, a twostep method was implemented that performed unsupervised clustering and then predicted the missing information. The first method is Density-based spatial clustering of applications with noise (DBSCAN) based spatial clustering which divides the diggers’ and buckets’ positional data into connected loading segments. Clear patterns of segmented bucket dig positions were observed. The second model utilised Gaussian process regression which was trained with the clustered data and the model was then used to infer the mean locations of the test clusters. Bucket dig locations were then simulated at the inferred mean locations for different durations and compared against the known bucket dig locations. This method was tested at an open pit mine in the Pilbara region of Western Australia. The experimental results demonstrate the advantage of the proposed method in inferencing the missing information of bucket-environment interactions and therefore enables miners to continuously track the material movement.

Jun 22, 2022

By W A. Take, M McKellar, A Walsh, S McDougall, S G. Evans

Recent tailings dam failures have heightened public awareness of the hazard posed by storage facilities for mining waste, illustrating the need for a more critical examination of tailings dam breach mechanisms and the potential mobility of liquefied tailings. Knowledge from tailings dam breach studies will help improve safety and risk management through more accurate inundation maps, dam consequence classifications and emergency preparedness plans. Tailings dams differ from conventional water retaining dams, although dam breach relationships used in practice rely heavily on relationships derived for breach processes from the latter. Physical modelling offers a controlled environment to advance the understanding of tailings dam breach processes, thereby allowing for modelling of simple geometry and boundary conditions to test hypotheses. The performed experiments investigate prototypical tailings dam configurations and material behaviour, with the objective of validating numerical models that will enable practitioners to better assess and mitigate tailings flows resulting from tailings dam failures. Research conducted in the Queen’s University Landslide Flume at the Coastal Engineering Laboratory has investigated the breaching of 1 m high dams with tailings geometry by overtopping initiated by a v-notch incised in the dam crest. This paper presents the initial results of the next stage of this research comparing the outflow hydrograph following loss of containment caused by shear failure to overtopping initiated by notch flow. The two dam experiments presented are constructed with similar dam and reservoir geometries allowing for a direct comparison of the effect on the outflow hydrograph of each failure event. Preliminary outcomes suggest that although both dam failure events are triggered from separate mechanisms their geometries allow for similar values of Q_peak to be reached. Future work is currently planned to expand the shear test series to explore the influence of failure mechanism on the outflow hydrograph.

Jul 1, 2021

The introduction of cement into underground backfilling at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited mines to improve mining efficiencies gave rise to several major problems, the magnitude of which had not been anticipated. These problems were 1. A loss of recovery in the milling circuit due to the presence of cement 2. The presence of cement-rich slime layers on the surface of the fills 3. The introduction of a safety hazard due to the slippery nature of the surface of cemented fills 4. The deposition of cemented slimes on the levels and in underground sumps and dams. The loss of revenue due to decreased metal recoveries considerably offset the gains from increased stoping efficiencies and the use of cement was substantially reduced while, (a) the Metallurgical. Department attempted to identify the chemical nature of the problem and overcome it, and (b) the Mining Department investigated methods of reducing cement contamination of the ore stream. As a part of this investigation the Mining Department added polymeric flocculants to the cemented fill pulp. Testwork was carried out in the following steps 1. The available Alfloc polymers were screened to determine which was the most effective and what was its optimum dosage rate. 2. This polymer was used in the laboratory to determine the reduction of surface slime, clarity of water, and effects on strength and percolation of fill. 3. Fills were placed underground to substan- tiate the laboratory work. /+. The polymer was then added to all cemented fills going underground to study its effect over a long term. The use of flocculants not only improved the distribution of cement in the body of the fill, but also the distribution of the fines fraction of the filling material, practically eliminated slippery surfaces and improved the clarity of the drainage water. Flocculant is now added to all cemented fills and restrictions on the use of cement are gradually being lifted.

Jan 1, 1973

By J Manuel, N Ware

Ideal iron ore sinter is produced by optimising the balance between coarse (+2 mm), stable ore nuclei and a reactive matrix consisting largely of fluxed -1 mm fines. The authors have previously published work evaluating the matrix melting behaviour of a number of fine ores, using techniques developed by CSIRO. The focus of that work was to demonstrate the contribution of the matrix to overall sinter quality, with the results showing a direct correlation between melting point, matrix porosity and strength. CSIRO has also developed a complementary test to study the behaviour of coarse ore nucleus particles in contact with the sinter matrix and provide an evaluation of their reaction and assimilation properties. This test provides valuable fundamental information that can be used to better understand the role of specific ore types and optimise blend composition.The CSIRO laboratory-scale assimilation test is carried out by embedding particles of ores of specific sizes into a fluxed matrix of known sinter blend composition, using real ores and fluxes, in a laboratory test that directly relates to pot-grate and plant sintering conditions. Samples are fired under controlled conditions in a tube furnace using a standard heating profile and a constant, low-oxygen potential atmosphere. These conditions simulate the actual sintering process while removing the effects of the many locally-variable parameters (eg temperature, oxidation potential and localised chemistry) that exist in the actual process, meaning that trends in behaviour can be more clearly seen. Designed as a compromise between the industry-standard pot-grate sintering test and a more fundamental test using chemical reagents, the aim is to isolate and evaluate the nucleus behaviour of an individual blend component to allow an improved understanding of the role that an individual ore plays in a specific blend. Measured cross-sections of the resulting fired samples provide a semi-quantitative measure of reactivity, while accompanying photomicrographs allow a qualitative assessment of assimilation properties (eg volume and distribution of secondary porosity generated during reaction).In this paper, to complement the previous work published on melting behaviour, nucleus particles were selected from hematite, hematite-goethite and goethite ores and embedded in a simulated plant sinter matrix. Drilled core particles of two sizes were tested at fixed temperatures simulating low- (<1300°C) and high-temperature (>1300°C) sintering conditions. The resulting assimilation properties are compared and discussed as a function of particle size, temperature and ore/sinter mineralogy. The implications for the contribution of each component to the prediction of blend sinter quality are also discussed.CITATION:Ware, N and Manuel, J, 2015. Fundamental nucleus assimilation behaviour of hematite- and goethite-containing ores in iron ore sintering, in Proceedings Iron Ore 2015, pp 77–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Large scale rhyolitic volcanism is an important process at some convergent plate margins because it leads to chemical differentiation of the upper.-crust and is responsible for the production of long lived near surface thermal anomalies; the Taupo Volcanic Zone is.a Quaternary example. The main features of the magmatic systems-of the zone. are the existence of large high level chambers containing homogeneous silicic magma which erupt at intervals of thousands to tens of thousands of years. Geochemical work on the deposits resulting from these eruptions has shown that with few exceptions the magmas have been remarkably uniform in their . composition throughout the history of the zone although individual batches with lifespans of the order of. one hundred thousand years can be recognised by subtle differences in trace element ratios. Basalt is a rare proportion of the rocks exposed at the surface but has played a major role as a medium for heat transfer and as an end member in chemical mixing processes.

Jan 1, 1987

Current attitudes by exploration companies towards working on another party's exploration permit or equivalent vary widely. That this is so is due to the virtual absence, on the one hand, of anything in the mining legislation in any jurisdiction that establishes what are the exclusive rights to explore, as opposed to apply for a mining tenement, that the grant of such an authority conveys on the holder, and on the other hand, of any code of ethics or set of guidelines to proper practise. By contrast, in most states and territories, if not all, it is an offence to enter onto a mining tenement, other than to cross it, without the consent of the holder, although until recently most field personnel would have been unaware of this and most explorers would have transgressed at one time or another. A similar vacuum exists where aerial surveys are concerned. There are in fact no guidelines. It has always been assumed that a party wishing to carry out such a survey was free to do so, without even an obligation to notify the holders of any tenements or permits in the area to be surveyed, let alone make available to them any data from the survey. Concepts of 'geophysical trespass' now being tested in the US also raise the possibility that data won from adjoining ground using geophysical techniques may be privileged. Attitudes now appear to be changing. In the absence of legislation or any code of practise, what does the industry regard as ethical behaviour? Do we need to define the rights and obligations of various parties more clearly, and if so, what should they be and to what extent will it be necessary to confirm them by legislation as opposed to adopting a code of practise? Will the existence of such a code in fact improve corporate practise?

Jan 1, 1995