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Research cruises dedicated to seafloor hydrothermal activity along the Kermadec arc first began with the Sonne-135 expedition in 1998. This was followed by the worldÆs first systematic survey for venting along an arc during the 1999 NZAPLUME I expedition. Since then, cruises dedicated to mapping plumes along the Kermadec arc include NZAPLUME II (2002), NZAPLUME III (2004) and ROVARK (2007). In addition, the manned submersible cruises SWEEP Vents (2004) and NZASRoF (2005) utilised the Shinaki 6500 and Pisces V, respectively, to sample in detail select hydrothermalsystems for mineralised samples, rocks and vent fluids. The ROVARK (2007) cruise was the first to deploy an autonomous underwater vehicle (ABE) along the arc which surveyed Brothers volcano at a far greater resolution than had been done previously by ships on the sea surface. While these expeditions have largely been led by GNS Science, together with its collaborators from National Oceanic and Atmospheric Administration, Pacific Marine Environmental Laboratory (NOAA/PMEL), significant contributions have been made by other groups from various nations, exemplifying the global interest in seafloor hydrothermal activity associated with intraoceanic arcs. This is an ASTRACT only. A full-length paper was not prepared for this presentation.

Jan 1, 2008

This paper introduces a new, safer bulk emulsion loading system for underground mining operations. The features and benefits of the equipment, along with the use of Dyno Nobel Inc patented gassed emulsion technology, is summarised in the application of a stope blast with very difficult and complex ground conditions. The paper describes methods used to optimise the amount of energy required to break the ore while protecting the integrity of the surrounding backfilled pillar.

Jan 1, 2004

By B Chappell

Backfill in the form of mine waste tailings has inherent problems associated with attaining adequate strengths upon placement. Fines are usually removed to ensure adequate drainage, which lowers the cohesive strength of the fill, leaving the fines to be placed in a tailings dam. Electro-drainage and electro-chemical grouting is examined to investigate its effects on densification and shear strength within a silty clay tailing having low permeability and shear strength. Two separate grouting mechanisms are observed for the iron and silica grouts used. Electroosmosis is associated with iron grout that deposits within the tailing matrix under a converging pH gradient, and increases the permeability of the tailing. This process initiates cation exchange and causes cementing of the granular contact points between the clays. Electro-phoresis causes sodium silicate solution to deposit silica grout in the voids of the tailings. The resultant effect of these mechanisms results in an increase in cohesion, leaving the void ratio of the iron grouted tailings as it was but significantly reducing the void ratio of the silica grouted tailings.

Jan 1, 1998

By A J. MacDonald, M P. Raffield

The South Deep massive orebody consists of 20 to 30 m of payable conglomerates ranging in dip from 11¦ to 20¦ and at depths of between 2400 m and 3400 m. The mine design process selected a mining method with a proven record of application that could be adapted to overcome the inherent difficulties associated with the depth, thickness and structural influences of the South Deep orebody. A modified cut and fill mining method provides a concentrated and highly flexible method of extraction. An integrated destressing cut will enable the modification of the stress environment such that it is suitable for massive mining operations. The choice of backfill type and stoping width in the destressing cut ultimately determines the characteristics of the stress modification and, as such, is critical to the success of the cut and fill operation. This paper discusses the decision process undertaken to determine the optimum backfill type and stoping width combination in terms of, conditions in the destressing cut faces and in the massive mining environment. Numerical modelling has been extensively used to analyse various scenarios to aid in the decision process.

Jan 1, 1998

By S Wainio, P J. Beckett, T Miller

Lichens are a symbiosis of fungi and algae. Air borne elements and gases are absorbed very efficiently over the entire surface of the lichen, because they have no protective structures such as a waxy cuticle or stomata. A survey in 1977 (one year before the Sudbury Regreening program began), indicated that several Cladonia spp had invaded the soil in Sudbury’s open birch woodlands. Pollution sensitive species such as Cladonia rangiferina and C. mitis occurred 20–25 km from the smelters. It was anticipated that the improvements in air quality and reclamation efforts would allow a natural invasion of pollution sensitive species into what once was a lichen desert that surrounded the smelters. The purpose of this project was to study the invasion of terricolous (soil-inhabiting) communities of lichens and mosses on reclaimed land in the Sudbury region 45 years after commencement of the Sudbury Regreening Program.

Aug 2, 2023

By N McIntyre, J Smart, J Ossa-Moreno, D Rivera

Hydro-economics is a field of research that analyses water resources from a multi-disciplinary approach (Harou et al., 2009). These models generally include one component that describes the water resources of the catchment being analysed (e.g. the physical behaviour of water), an economic component that describes users’ water demand function (changes of willingness to pay relative to availability) and a coupling methodology. These models go beyond calculating cash flows for water investments and analyse the economic behaviour of users when facing water shortages or surplus. In other words, water demand curves are defined for each water user (e.g. urban, agriculture, mining, environmental and hydropower), and they are used to retrofit the water resources component. As a result, the model approximates the catchment scale response to droughts and wet periods, including the effects of water markets, restrictions, recycling, water sharing and any cooperative efforts by users to adjust to changing climate conditions.These models are usually focused on agriculture and urban users, the main water consumers in most catchments, but they have sometimes included environmental, industrial and hydropower users (Bekchanov, Sood, & Jeuland, 2015). Nevertheless, although a relevant user of water in several catchments, the mining industry has been rarely included. This paper is part of an ongoing project that addresses this gap by developing a hydro-economic model in the upper section of the Aconcagua River in Chile. The aim of the paper is to analyse the sensitivity of the outputs of the model to changes in input data, both hydrological and economic, and to develop insight on usefulness of such models for reducing water conflicts in mining regions.CITATION:Ossa-Moreno, J, McIntyre, N, Smart, J and Rivera, D, 2018. Sensitivity of a hydro-economic model in a mining region to changes in hydrological and economic inputs, in Proceedings Life-of-Mine 2018, pp 52–55 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By C J. McKenzie, D F. S Natusch

The lignite deposits of Southland and Central Otago are a potentially significant energy resource for New Zealand. Current estimates put the technically mineable lignite reserves at 5.3 billion tonnes, which is more than ten times the energy content of the Maui gas field. Thus, the strategic importance of the lignite as a basis for maintaining current levels of self-sufficiency in transport fuels, or as a possible feedstock for electricity generation, deserves full investigation. The full extent of the lignite deposits was only recently established as the result of a scout drilling programme undertaken between 1976 and 1979 by the Mines Division of the Ministry of Energy, and from companion studies conducted by the New Zealand Geological Survey. These discoveries of large quantities of lignite coupled, at the time, with rising oil prices, raised the prospect of their development for production of transport fuels.

Jan 1, 1983

By M J. Saynor, J B. C Lowry

The Ranger Uranium Mine is located in the wet-dry monsoonal tropics approximately 250 km east of Darwin in the Northern Territory of Australia (Figure 1). Mining of open-cut ore bodies commenced in 1980 (Pit 1) and ceased in 2012 (Pit 3) and milling and production are scheduled to cease by 2021. At the conclusion of mining and milling operations, mine tailings will be returned to the mined out pits 1 and 3, which must then be physically isolated from the environment for at least 10,000 years (Australian Government 1999). The final landform also needs to have sufficient mitigation measures in place to ensure that areas downstream are not impacted by erosion products from the mine site. The proposed post-mining rehabilitated landform will cover approximately 847 hectares (8.5 km2) which represents an area that has the potential to supply sediment to catchments and streams downstream. One method of reducing runoff and associated sediment is the construction of rip lines along the contour to slow down the runoff velocity and to also trap fine sediment and nutrients in the depressions to assist vegetation growth.CITATION:Saynor, M J and Lowry, J B C, 2018. The impact of rip lines on erosion at the Ranger Mine Site, in Proceedings Life-of-Mine 2018, pp 150–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By N Winkelmann

Underground coal heating is a significant hazard in some coal mines. The broad principles of how underground coal heatings occur is reasonably known, however the technique for locating the heatings in often inaccessible goaf has been proved to be difficult. Since 2002, CSIRO, with the support of the Australian Coal Association Research Program (ACARP) has been undertaking investigations to apply and develop innovative surface-based radon technique for locating the underground heatings in Australia. This paper presents the progress of the investigation.

Jan 1, 2005

By Wang J, Ma Y, Jia H

The Hedong Gold Mine is located in the Yan(ai area, tihandong hroo%ill, e. China. It is an underground mine with an annual gold output of some 700 0(H) grams. The orebody is located on the edge of the Wanger Shan metamorphism zone, and the hangingwall of orebodies is thus defined by a prominent set of fractures. The proximity of the metamorphism zone and the inclusion of the fracture set ensure that both the orebody and the country rocks are unstable. The main orebodies dip at an angle of between 40 to 45¦, with a strike length of 160 metres and a horizontal width of 50 metres. Surface subsidence in the area is not permitted. Cut and fill mining is usually practiced. As the mining operation proceeds to greater depths, the ore grade is diminishing and it is necessary to find a more efficient stoping method. Sublevel open stoping with sequential extraction and filling of each sublevel has been designed and applied in situ. This new mining method is called 'sublevel open and fill stoping method' in the mine. Experience to-date is that new mining method is Satisfactory.

Jan 1, 1998

By C Antonio, R Narayan, A Scheuermann, S Quintero, M Edraki, M Ziemski

Tailings are mostly loose material and can be classed as non-plastic sandy silts. They also tend to have low permeability, resulting in slow consolidation (settling) rates and low shear strength, even after consolidation. These qualities make them prone to liquefaction and, therefore, physical instability. In contrast, coarse waste rocks possess high shear strength and permeability when stacked in dumps. However, air and water flow-through the voids can cause acid mine drainage (AMD) with significant undesirable environmental implications. Combining the two waste streams before disposal by mixing presents a potential opportunity to harness the desirable properties of both waste streams. This practice is termed co-mingling and is prevalent within the coal processing industry. Co-mingling of metalliferous mine tailings is, however, a relatively new concept. By combining the coarse waste rocks and fine-grained tailings streams, the fine tailings tend to fill the voids between the waste rocks, reducing hydraulic conductivity and advective air (oxygen) flow into the rocks, thus possibly reducing acid mine drainage (AMD). Conversely, tailings are introduced to large frictional particles from waste rocks, providing reinforcement, stability, and possibly improved drainage. New separation methods are being introduced to the mining sector, which have the capacity to extract waste with significantly larger particle sizes. High Voltage Pulse (HVP) is a technology in which relatively coarse particles ranging in size from 30 to 100 mm are exposed to an electric pulse discharge. This pulse preferentially fractures mineralised particles while leaving unmineralised rock (gangue) intact. The stream can then be passed via a screen, with smaller mineralised particles reporting to the undersize and removing coarser unbroken barren particles, thereby eliminating waste. Coarse particle flotation (CPF) is another emerging new technology in metalliferous mining that applies flotation separation to coarser particles than conventional flotation. These new technologies produce different tailings (waste) streams with varying physical characteristics and possibly surface chemistries. This research aims to test new tailings mixtures by applying the co-mingling concept to blend the reject streams generated by these two technologies (HVP and CPF) with the tailings produced by conventional flotation. Combining different waste streams before disposal can improve stability and potentially reduce the acid mine drainage (AMD) rate, thus enabling early access to the tailings storage facility for rehabilitation and closure.

Aug 2, 2023

There are still vast areas of Australia in which either the hydrocarbon potential has already been indicated but from which no hydrocarbons have been produced or else are completely untested. Despite the lack of recent new oil discoveries, it is anticipated that initial gas discoveries in these areas will be followed by oil discoveries as has happened historically. General exploration activities are continually providing new information that is being input to update previous hydrocarbon assessments for Australia, and all indications are that future exploration efforts will discover a lot of gas, some small oil pools and there is a chance to prove a major new oil province. Because of this, it is anticipated that reserves growth will continue at the average historical rate of about 200 MMB/year until the year 2000. The most frequent scenario will be costly exploration resulting in small oil discoveries and high development costs. This, in the past, has resulted in low profitability for Australian oil exploration, but windfalls for the Australian government.

Jan 1, 1981

By Frfas C, Parrilla F, Regife J. M

A project to develop the Zinclor electrowinning cell to industrial size is being conducted at Tecnicas Reunidas' Research and Development Centre with Spanish Ministry of Industry support. This project is the final development phase in zinc electrowinning from a chloride medium, the highest ZINCLOR technology development level prior to the industrial scale having already been reached. This paper covers the outcomes and conclusions corresponding to project Phases 1 and 2: Process Selection and Industrial Electrodes (1 m2) design and testing. The most important achievement reached is that there are presently available industrial cathodes and anodes for the Zinclor diaphragm cell giving an optimum response for zinc chloride electrowinning with unit power consumptions between 2.65 and 2.80 kWh/kg Zn, depending on the diaphragm type. Standard electrolysis conditions were: 65 g/L ZnC12, 3 g/L HCl, 160 g/L NaCl, 350 g/t Zn arabig gum as the addition agent, 36¦C, and 400 A/m2 current density. The selection of electrodes, diaphragms and organic additives for the industrial scale tests have been optimised. The complete electrowinning cell development, with electrodes having an active area of I m2, enables the evaluation of Zinclor Technology application for industrial processes.

Jan 1, 1993

By M D. Melville, B C. T Macdonald, T D. W

The surface waters in regions with acid sulfate soils (ASS) can contain high concentrations of acidity and dissolved metals. These soils cause problems for agriculture, construction and development. The water can be neutralised through many techniques, however a technique that is low in maintenance and low in cost is most desirable. Due to the vast spread of ASS along AustraliaÆs coastline an expensive and high maintenance solution would not be cost-effective. In this study, a passive treatment system that has been used to neutralise acid rock drainage has been applied to treat ASS water. This system is commonly referred to as an oxic limestone drain (OLD) or an anoxic limestone drain (ALD) depending on the waters dissolved oxygen concentration. The system that has been developed for ASS has a similar closed system to the OLD or ALD, that traps the carbon dioxide which forms when limestone reacts with acidic water. It has been called a closed tank reactor (CTR) and is constructed by placing limestone into an airtight tank. A common problem that will occur when acidic water with a high concentration of dissolved metals reacts with limestone is the formation of metal oxy-hydroxide precipitates. These precipitates can coat or armour the limestone and reduce its reactivity. To minimise the accumulation of precipitates in the CTR, perforated subdrains have been installed. It is anticipated that high water pressure and flow through the subdrains will remove some precipitates. A sump has also been installed at the base of the tank to collect precipitates that settle under gravity. The CTR has been tested for 70 days at a sugar cane farm located at McLeods Creek, NSW. Within this time the sump and subdrains have been used to flush the system. An orange solution was produced during flushing and it is believed to contain iron and aluminium precipitates. The initial performance of the CTR raised pH by at least one unit. Almost all dissolved aluminium was removed and more than half the dissolved iron. The total titratable acidity ranged from 17 - 92 mg/L CaCO3 in the initial month of monitoring. After passing through the CTR the acidity was reduced to zero. The performance of the CTR during the last few days of monitoring decreased. This is believed to be due to a pulse of water with higher acidity and dissolved metal content that lasted a week. In this pulse, the acidity reached 307 mg/L CaCO3 and the total dissolved aluminium reached a maximum of 24 mg/L. Higher concentrations of dissolved metals may have been the cause for lower performance due to increased precipitation and coating on the limestone.

Jan 1, 2003

Gold mineralisation at Wapolu lies within an exposed arcuate zone at the decollement contact between a basement dome of high grade metamorphics and an overlying ophiolite sequence. This contact was originally a thrust fault which has since become a decollement zone for gravity sliding in association with basement doming. Hydrothermal models for the gold mineralisation postulate an epithermal system in which fluids were channelled up the decollement with boiling of those fluids causing hydrothermal brecciation and subsequent gold deposition. The alteration assemblages, fluid inclusion data and geochemistry indicate that the upper levels of the system are exposed.

Jan 1, 1987

By B Godel, E R. Ramanaidou, M Verrall

Fortescue Metals Group Ltd Iron Bridge (IB) operation is a magnetite deposit located in the Pilbara region of Western Australia situated around 145 km south of Port Hedland. This Mesoarchean deposit belongs to the 3230 Ma Pincunah banded-iron formations (BIF), a member of the Kangaroo Caves Formation, Sulfur Springs Group (van Kranendonk, 2000).

Sep 18, 2023

By R B. Wanty

Historically, most investigations of biogeochemical cycling in acid rock drainage systems involved synoptic sampling over longer time periods (one sample per week or month) or intensive time series studies over a few hours or days. However, many important episodic loading events, such as seasonal meltwater and storm events occur on timescales that are rarely observed by these traditional sampling approaches. Monitoring these transient processes, which may contribute the bulk of the annual metal loading, is essential for accurate assessment in acid rock drainage areas. Recent work also has demonstrated dramatic diel (24 hour cycle) variations in trace metal concentrations in response to diel changes in temperature, pH, oxygen, and photochemical cycling (Brick and Moore, 1996; Nimick et al, in prep). To characterise a system that may respond to diel, seasonal, and episodic events, a monitoring program must sample at a frequency that captures the details of these major forcing events. We developed two novel instruments, the Zn-DigiScan and the DigiSampler to examine low and high frequency temporal changes in acid rock drainage areas. The Zn-DigiScan is a battery powered real time in situ chemical analyser designed for long-term deployments with hourly analyses of Zn. Stream physical parameters (temperature, conductivity, dissolved oxygen, pH, turbidity, etc) were measured every 15 minutes with a water quality sonde. The DigiSampler was developed for the long-term daily sampling of biogeochemically active elements and can take either discrete samples or samples integrated over 24 hours. The DigiSampler collects 2 ml samples in a Teflon coil which are separated by 0.2 ml nitrogen bubbles. The sample coil is returned to lab and the 2 ml samples are diluted 1:10 and analysed for trace metals by ICP-MS. Initial results from a three-day deployment at Fisher Creek, MT, USA have successfully demonstrated the ability of the Zn-DigiScan to record Zn concentrations at levels below 100 ¦g/L. Zinc concentrations measured at 30 minute intervals in Fisher Creek showed a diel cycle with low values of ~25 ¦g/L in the late afternoon and increasing to ~60 ¦g/L by early morning. Zn concentrations were inversely related to temperature and pH, suggesting that temperature and pH dependent adsorption was the main factor controlling diel Zn fluctuations. Initial deployment of the DigiSampler also was successful, revealing diel cycles in Zn, Cu, and Mn. Comparison of trace metal samples collected by the DigiSampler showed good agreement with samples collected by an Isco automated water sampler, demonstrating that the DigiSampler can collect clean samples for trace metal analysis at the low ¦g/L range.

Jan 1, 2003

By N Swiegelaar

Loubert Witbank is a defunct coal mine situated near Ermelo in South Africa. Mining ceased in 1992, and within a short period acidic decant occurred, with a significant impact on the regional catchment. The problem was studied during 1996/1997, and the site remediated in 2001/2002 by the Department of Water Affairs and Forestry. Remediation involved primarily submerging of carbonaceous material, backfilling of voids, and capping of the site. Acidic water with high iron levels was also neutralised and discharged. The project was used to assess the cost benefit of different options to the downstream users, from which target expenditure was derived for the various improvements. The cost benefit analysis for neutralisation provided a basis for the investigation of low-cost neutralisation options that are robust enough to be applied in a remote environment.

Jan 1, 2003

By B G. Blacka, O Salisbury, K W. Mills, R G. Jeffrey

Whitehaven Coal Limited operates an underground longwall mine near Narrabri, New South Wales. The mining horizon in the Hoskissons Seam is overlain by a 16–20 m thick unit known as the Digby Conglomerate, a unit that is sufficiently massive to have potential to cause a windblast during first caving at the start of each longwall panel and periodic weighting throughout the panel. A program of hydraulic fracturing has been successfully used to precondition the conglomerate strata to increase its caveability at the start of each panel. This paper presents a system of temperature monitoring that was used successfully to measure hydraulic fractures at Whitehaven confirming their rate of growth, orientation and interaction with previously placed hydraulic fractures.CITATION:Mills, K W, Blacka, B G, Jeffrey, R G and Salisbury, O, 2014. Temperature monitoring of hydraulic fractures used for preconditioning massive conglomerate strata to reduce windblast, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 189–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By I Jabou, D G. Blazak, L C. S Hogarth

The R70 test is a good indicator of coal reactivity to oxygen and is commonly used to provide a rating of propensity for self-heating. Tests performed by The University of Queensland Spontaneous Combustion Testing Laboratory have resulted in the development of a large database that shows the impact of coal quality on this parameter. From these results it is possible to infer an R70 value, which can be used to gain an appreciation of the intrinsic coal reactivity before it is even tested. However, any interpretation of R70 values must consider the influences of coal rank, mineral matter and moisture content to provide a better understanding of the spontaneous combustion risk of a particular coal.

Jan 1, 2005