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Portman Mining Pty Ltd very successfully operated the Ferro GullyNorth Mine in the Hamersley Province of Western Australia to satisfy a contract for the delivery of six million tonnes of iron ore in less than two years to the Mount Newman Mining Co Pty Ltd. The high-grade ore extracted from Ferro Gully North Mine was unusual in that, not only was it within the Joffre Member of the Brockman Formation, but it was rich in red ochreous hematite and martite and very low in phosphorus.

Jan 1, 2001

The use of black and white and colour infrared film in remote sensing of natural resources, is reviewed. In heavily-forested areas such as New Zealand, the main value of the method is in surveying the vegetation cover to detect the existence of plant communities characteristic of specific geological formations, By contrast, in and areas of Australia where the vegetation cover is sparse and where rocks and soils are well exposed, the method can be used in detecting different rock types or other geological differences.

Jan 1, 1971

Potential hlghwaJl mining reserves in Australia are large, but geotechnical and operating conditions are quite different from those where highwall mining has evolved in the USA. In order to achieve safe and effective resource recovery, equipment and procedures should be developed to penetrate 250 m in the Australian mining environment. This paper identifies key auributes to be incorporated in such machinery and methodology. These suggestions are intended to promote discussion on innovations to satisfy Australian requirements for highly productive, safe and environmentally acceptable techniques.

Jan 1, 1993

The first grant of land rights in Australia was pursuant to the Aboriginal Land Rights (Northern Territory) Act 1976. That Act has been at the core of the dispute between land rights and miners' rights. The mining industry believes that the Act, in giving a right of veto to Aborigines with respect to exploration and mining on Aboriginal land, has been responsible for a stagnation in exploration amd mining activity in the Northern Territory. In February 1985 the Commonwealth Government released for public comment its preferred model for national land rights legislation. The model has been opposed by the mining industry because it believes, first, that land rights is a matter which should be left to the States and, secondly, that the detailed mechanisms contained in the model constrain the industry in the manner of the Northern Territory legislation. Aboriginal leaders have opposed the model because it does not, in their view, measure up to undertakings given by the Commonwealth Government and, in addition, it provides for amendments to the Northern Territory legislation which are likely to result in the loss of the Aboriginal veto right. Are land rights and miner's rights compatible? The answer is yes provided all parties, including Governments, are prepared to talk and compromise and Governments recognise that the grant of land rights and any control by the Aboriginal people of exploration and mining on their land is not a substitute for raising the living standards of Aborigines as a significant group of disadvantaged Australians.

Jan 1, 1986

In most States of Australia it is a legislative requirement for underground mines to have a separate means of egress from the normal means of ingress to permit the safe evacuation of workers to the surface in event of an emergency. Such egress may be in the form of a ladderway equipped shaft/underlie or trafficable incline/decline. Additionally, there is a general requirement to have one or more airways, separate to the main shaft or other principal entrance of an underground mine, extending to the lowest level to permit ventilation to all parts of the mine. Fulfilling these requirement is difficult in the development phase of a mine when access underground is achievable by only a shaft or decline in the process by being sunk. What is frequently practiced in Australia is for production to then commence, sometimes in association with continuing development, in the same configuration without the establishment of this separate method of egress to the surface nor additional airway/s with reliance on refuge chambers to cater for back up in any emergency. Not only, could this jeopardise the health and safety of workers in case of an underground emergency it could be construed as a statutory breach of legislation. While recognising that refuge chambers are often used throughout underground operations nowadays their equipping and the criteria for their location needs to be bought into focus. This presentation discusses how such legislative requirement can be met alongside the use and appropriateness of refuge chambers.

Jan 1, 1998

Alaska Native corporations, as representatives of the aboriginal inhabitants of Alaska, control the mineral rights to 18 million hectares of Alaska, approximately 12% of the state. These corporations were established through legislation passed by the United States Congress in 1971 designed to settle the land claims of the Native peoples of Alaska. Twelve corporations, each representative of a specific geographic and cultural region, were established and granted the mineral rights to most Native lands in their respective regions. Since that time the Native corporations have taken an active role in mineral development in the state. Generally through agreements with established mining companies, Native corporations encourage balanced exploration and development of their lands. Substantial mineral potential has been recognized on Native corporation land, which includes holdings in many historic mining districts of Alaska. Several world class deposits have been discovered on Native corporation land, including the Red Dog zinc-lead deposit, which began production in late 1989. The experience of Alaska Native corporations demonstrates that aboriginal peoples can be very positive forces in resource development.Alaska, although remotely located in the Northeast corner of the Pacific Basin, is playing an increasing role as a supplier of natural resources to the region and the world. Most of Alaska's privately held natural resources are owned by the aboriginal inhabitants of the state. These aboriginal inhabitants, now collectively referred to as Alaska Natives, have emerged in the last two decades as having a major international impact in mineral resource exploration, development, and production.

Jan 1, 1990

By A Goldstone, M Fitzpatrick

Contemporary mine wastewater flows are subject to stringent water quality standards before discharge to local waterways. Strict criteria are often applied as a result of fears of extensive acid mine drainage; a feature of the many abandoned mine adits around the Coromandel, Central Otago, and the West Coast. In most cases the USEPA water quality criteria have been used to set treated wastewater discharge water quality standards. In future it is possible that the recently published ANZECC water quality criteria guidelines will be used for this purpose. The ANZECC guidelines also provide for the establishment of discharge criteria at specific sites, rather than accept the trigger values. The use of site-specific criteria for treated wastewater mine discharges was pioneered at the Golden Cross gold mine, near Waihi, in the late 1980s. The procedure used to derive water quality criteria was based on USEPA guidelines. In developing the Golden Cross criteria, only species that occur, or are similar to those that occur in the Waitekauri River were used. The mine commenced discharge of treated wastewater in 1991, and macroinvertebrate communities in the vicinity of the discharge point have been regularly monitored twice a year for the past 12 years. Despite fluctuations in community composition and abundance over that period, no permanent significant changes in the macroinvertebrate communities occurred between sites above and below the treated wastewater discharge. The success of the site-specific criteria at Golden Cross has shown how the application of this methodology can result in the protection of aquatic life while allowing for the discharge of treated mine wastewater.

Jan 1, 2003

By K Guilfoyle, A Robertson

In the mid-1970s, trucking ore from 400 m depth to the surface was perceived to be the practical and economic limit for metalliferous underground mines. Improvements in truck design and decline development resulted in the economic depth of haul exceeding 600 m by the mid-1990s. Today, mine operators and contractors are planning to use trucks for ore haulage from depths in excess of 1000 m. The authors of this paper estimate that there are in excess of 300 diesel-powered trucks operating in mines in Australia, and that by the year 2005 more than five per cent of these trucks will be æroad trainsÆ (ie trucks towing powered trailers or truck-trailer combinations). This paper examines the road train concept, presents cost and performance data and describes the advantages and disadvantages of the road train system as well as proposing the types of applications for use of road trains in Australian metalliferous underground mines. Truck performance is based on payload and average speed (expressed as tonnes x kilometres per engine hour (t km/h)). A road train with a powered trailer has a large payload capacity and two engines to provide a high ratio of power to gross weight. Thus it is possible to exceed 300 t km/h per cycle for an average haulage gradient of 1:9 compared to 250 t km/h for conventional articulated dump trucks (ADTs). It is likely that road trains in excess of 100 t capacity will have application for level ore haulage at large mines in Australia.

Jan 1, 2002

An investigation was performed to determine the sequence of events which caused the 1987 surface subsidence and related damage to several homes in Walker County, Alabama, USA (see Figure 1). Surface affects compared to mine maps indicated the subsidence to be mine related. However, two coal seams had been worked under this area. The upper seam, the American seam ranged from 250 to 280 feet beneath the surface in the area in question. It was mined-out before 1955 by room-and-pillar method leaving in place narrow-long pillars to support the overburden strata, and abandoned in 1955. The lower seam, the Mary Lee seam, ranged from 650 to 700 feet beneath the surface. The Mary Lee seam had been abandoned in 1966 and subsequently became flooded. The dewatering of the Mary Lee seam workings in 1986 caused the submerged pillars to be exposed to the atmosphere. Due to multiple seam mining and the fact that workings had been inundated then dewatered, a subsurface investigation ensued to determine the sequence and ultimate cause of surface subsidence. Core sample tests with fracture analysis in conjunction with "down-the-hole" TV camera inspections provided necessary information to determine that the subsidence started in the lower seam and progressed through the upper coal seam to the surface. Evidence from the investigation program established that dewatering of the lower seam workings caused the marginally stable support pillars and the roof to collapse. This failure triggered additional subsidence in the upper seam which broadened the area of the influence at the surface.

Jan 1, 1992

For many years the mining industry at Broken Hill, New South Wales, Australia, was carried on with just sufficient attention to underground ventilation and hygiene conditions as to keep pace with necessity. However, the campaign against industrial diseases in other mining centres (notably South Africa) some years ago, brought the subject more prominently before local mining engineers.Throughout a period of several years, gradual improvement has been effected, and at the present time industrial hygiene is considered an essential part of the production operations of the various companies.In June, 1918, a move was first made by the Board of Trade advising an inquiry respecting the health of employees engaged in the metalliferous mining industry in the State of New South Wales. At the end of that year, a recommendation was made to the State Government by the Board of Trade that a Techni.cal Commission of Inquiry be appointed to examine and report upon the dust conditions of the metalliferous mines at Broken Hill. Following this a second report presented in 1919 made specific recommendations in respect to the scope of such a Commission. A Technical Commission of Inquiry was accordingly appointed and arrived in Broken Hill to inquire into the prevalence of miner's phthisis and pneumonoconiosis in the mines. Early in March, 1920, the examination of all mine employees commenced, and the work was completed in June, 1920. The full report of the activities of the Commission and the conclusions arrived at was officially published at a later date. Based on the recommendations...

Jan 1, 1940

It is proposed to deal with those raw materials which are produced in South Australia to meet the needs of the country's steel industry. They are chiefly, iron ore, limestone and quartz.Iron ore and limestone are fed to the blast furnaces of Newcastle and Port Kembla together with coke to produce the hot metal charge for the open hearth steel furnaces.They are also qsed in the raw state in the steel furnaces to assist in the conversion of the hot metal to steel. The iron ore is quarried from' Iron Knob and shipped from Whyalla to Newcastle and Port Kembla, whilst the limestone is supplied from the deposits at Rapid Bay and shipped in the same manner.Quartz is used in the manufacture of ferro-silicon, an alloy which is added to the ladles of molten metal tapped from the open hearth furnace in the case of almost every grade of steel. It is obtained from a quarry situated between Iron Knob and Whyalla, and shipped to Newcastle.IRON OREWith the exception of several small quarries situated at Breadalbane, Cadia, Cowra, Crookwell, Michelago, Jerrawa and lerraama in New South Wales, the iron ore requirements of Australia's steel industry to date have been met from Iron Knob and the Middleback Range in South Australia.Several of the small deposits in New South Wales were worked during the war years of 1941-44 during the shipping emergency and produced 1,355,417 tons, compared with an output of approximately 43,000,000 tons from Iron Knob between 1901 and 1949.

Jan 1, 1951

The New England Fold Belt forms the easternmost and youngest section of the Tasman Fold Belt System of eastern Australia. From middle Palaeozoic to Early Cretaceous time it was the site of extensive episodic calc-alkaline magmatism related to W-dipping subduction. The oldest rocks may have formed at least partly in a volcanic island arc, but from the Late Devonian, the fold belt developed as a convergent Pacific-type continental margin. For Late Devonian-Carboniferous time, parallel belts representing continental margin volcanic arc, forearc basin and subduction complex assemblages can be recognised. Major dextral transform faulting may have offset parts of the fold belt in the Late Carboniferous. In addition, some structural blocks which appear to be out of place in the overall palaeogeographic setting are possible exotic or suspect terranes. A great variety of lode deposits ranging in age from middle Palaeozoic to Early Cretaceous is present in the New England Fold Belt. The vast majority of these are related to emplacement of extensive granite plutons and eruption of continental silicic volcanics in Late Permian-Late Triassic time. However, volcanogenic massive sulphides and volcanic hosted epithermal gold-silver deposits in older rock sequences include one major orebody (Mount Morgan) and several important ones (Mount Chalmers, Cracow, Silver Spur, Cangai and Halls Peak). Some problematical deposits are best classified as metamorphic-hydrothermal. These include gold-bearing quartz reefs and stockworks in sedimentary host rocks, the most important of which are at Gympie, and antimony-gold- tungsten mineralisation in the New England area, mainly at Hillgrove.

Jan 1, 1987

The Beverley uranium mine û now in production in the remote north of South Australia at1000 tonnes per annum û was established to meet a projected, but little-recognised shortfallin primary supply of uranium for the nuclear industry in the early part of the 21 st century. Inthe context of AustraliaÆs lack of bi-partisan support for uranium mining and the nuclearindustry, a four to five year window of opportunity existed from 1996 to establish the mine.During this period, Beverley achieved a number of firsts including: the first ISL mine inAustralia; the largest ISL mine in the world and the first to produce more than 500 tonnes ofuranium in its first year; the first to be established under a new Native Title regime in SouthAustralia; and the first to be established under a revised South Australian Mining Act.Beverley was brought into production against the background of: hostile opposition fromanti-nuclear activists; a suspicious and at-times hostile media; a regulatory and politicalcommunity that was unfamiliar with ISL mining; commercially unsophisticated Aboriginalgroups; an inexperienced engineering industry; and the vagaries of development in a remote,semi-arid location with neither population nor infrastructure. The lessons that can be learnedfrom Beverley showed that û like much in life û flexibility and timing are crucial.

Jan 1, 2002

The Ok Tedi copper and gold mining project is located in the headwaters of the Fly River system in western Papua New Guinea. The project's Feasibility Study was completed in 1979, and in- cluded a preliminary environmental assessment and an environ- mental management program. Construction commenced in 1981, an environmental impact study was completed in 1982, mining and treatment of gold ore commenced in 1984, staged construction of copper ore processing facilities took place during 1986-1988, and a further major environmental study was carried out for the operat- ing mine during 1986-1989. A very considerable data base of environmental information has been assembled by means of a comprehensive monitoring program. Environmental management criteria applied to the Project have reflected the stages and nature of development and operation. Criteria have been designed to regulate potential environmental impacts in the Fly River. An Acceptable Particulate Level of suspended sediment is the principal criterion. Compliance is con- ditional upon -a limited reduction in fish biomass, and upon dis- solved and particulate copper concentrations not exceeding predicted values at various locations throughout the river system. The criteria were established by the Government of Papua New Guinea following evaluation of environmental studies undertaken by the mining company. Compliance is checked by a detailed monitoring program, frequent reporting and statistical evaluation of monitoring results.

Jan 1, 1991

In the human body, the balance between heat production and heat loss is continuously being disturbed, either by changes in metabolic rate (work being the most influential) or by changes in the external environment (heat stress), which alters heat loss. These changes in body temperature can adversely affect the function of body systems and organs. As a result, heat production or heat loss processes are triggered in order to restore normal body temperature (36 - 37¦C). If the heat generating systems of the body are excessive or the environment hostile then the capacity of the body to maintain thermal homeostasis is exceeded and can lead to a serious threat to health, or even death. This health deficit can severely affect an individualÆs capacity to work optimally; the end result is both poor productivity and health. Strategies to minimise or eliminate this effort will benefit both the health of workers and the productivity of companies. The principal strategies to reduce the effects of the environment on workers are: engineering interventions: to improve environmental conditions and reduce heat stress; and a comprehensive working in heat protocol: with provisions to identify risk situations and procedures to be adopted in relation to these. The above points will be discussed in detail with practical and simple strategies proposed to combat the deleterious effects of heat in mining.

Jan 1, 2005

By T Nixon

A common problem for many mines is insufficient total primary airflow or insufficient airflow in the correct places as the mine changes over its life. This has a number of impacts on the business operation and may result in the need for a major and unexpected capital upgrade of the system, cancellation of a planned production increase, reduction in production targets, increased operating costs, failure to provide contracted metals to customers or acceptance of substandard conditions in the workplace. In some cases, it can even result in premature closure of the mine. In recent times, higher metal prices have given an expected economic boost to many mines, potentially prolonging their life but simultaneously requiring the mine to develop to deeper depths or requiring assets such as shafts and fans to have their service life extended. Insufficient primary airflow is a particular problem in deeper mines as the ventilation circuits become longer, more convoluted, have higher shock losses and the actual airflow requirements increase due to a combination of leakage, dispersion of the workings and the problems of managing the additional heat loads due to higher virgin rock temperatures and autocompression. This paper discusses the reasons why mines experience unexpected shortfalls in primary ventilation capacity with its associated impacts on metal targets, profits and frequently on the health, safety and morale of the workforce, as well as its productivity.

Jan 1, 2008

By S Miller, R Smart, J Thomas

Single-addition and sequential net acid generation (NAG) experiments were carried out on natural and prepared samples with varying contents of organic matter and pyritic S. Results show that carbonaceous matter can produce significant quantities of organic acids during peroxide oxidation in the NAG test, which leads to overestimation of acid-forming capacity and misclassification of benign samples as potentially acid forming (PAF). Organic matter effects were most pronounced in samples with low S (less than 0.5 per cent) and total organic carbon (TOC) contents of greater than seven per cent. The single-addition NAG test will tend to overestimate acid potential in samples with little or no pyrite and high organic matter content, potentially leading to sample misclassification. High pyritic sulfur samples tend to show little difference in single-addition NAG acidities with increasing organic matter, and it appears that pyrite is preferentially oxidised by peroxide when present in significant concentrations (greater than one per cent pyritic S). In sequential NAG tests overestimation was greatest in samples with little or no pyrite, but highly carbonaceous (>20 per cent TOC) pyritic samples were affected in later stages as the pyrite was depleted. A modified NAG method is proposed to account for the relative proportions of pyrite derived acidity and organic acidity in a given NAG solution.

Jan 1, 2003

There have been many developments in recent years in pipeline transport to enable them to be more widely used in industry. Substantial tonnages of materials that are not affected by water, such as coal and other minerals, aggregates and wastes, can be moved over considerable distances in quite small diameter pipes. Where there are no existing road or rail facilities, long-distance pipelines are usually cheaper to install, and this advantage increases in difficult terrain. Pipeline operators all over the world assert that hydraulic lines pay for themselves in a relatively short time, in spite of the heavy capital outlay, and this is equally true for lines convey-ing slurries or pastes within a plant complex.'This paper reviews some of the more important investigations in the hydraulic transport field. Although reference to systems carrying a wide range of materials is made, the majority of recent published data centres on coal transport.The paper looks at the application to a wide range of particle sizes, the development of non-aqueous slurrying media and coal/water fuels. The review also looks at some of the equipment being proposed to provide more reliable operation and in particular the range of solids-handling pumps now available.-The paper goes on to identify areas where further research and development is required and some of the many organisations undertaking this work.

Jan 1, 1985

This paper summarises some observations regarding the way SAG and AG mills work based on the last ten years of pilot plant operation, grinding circuit design and operational reviews for various projects in Australia and overseas. The main purpose is to promote discussion on key factors influencing breakage in a SAG mill. The focus of the paper is on two questions: How do mill lifters and liners really work and have an effect on grinding? How does the mill charge composition impact on grinding performance? The focus of the paper is on observations of mill behaviour in both pilot plant trials and plant operation, particularly on Cadia ore. DEM, by others, and JKSimMet modelling of SAG mill performance have greatly assisted in forming the ideas expressed in the paper and both are valuable tools in developing our understanding of the comminution process. Put in the æextremeÆ form the major observations and conclusions expressed in this paper are that: the main purpose of mill lifters is to reduce mill liner wear and not to promote rock breakage; the often promoted theory that balls impacting the ætoe of the chargeÆ is a dominant form of breakage is incorrect; and fines production in a SAG mill is primarily a function of the rock load mass, with a secondary dependence on ball load for any given circuit configuration.

Jan 1, 2007

Mining of the silver-lead-zinc orebodies at the George Fisher Mine officially started in 2000. A review of mining performance to date shows that many of the extracted primary stopes have experienced some degree of hangingwall dilution. The degree of hangingwall failure in the stopes became progressively more extensive throughout mining of the orebodies in 2001 and 2002, culminating in the unplanned catastrophic failure of the 744D stope in which the ore between 13C (2683RL) and 12L (2714RL) sublevels caved into the previously mined cavity between 13L (2654RL) and 13C sublevels. This was followed several months later by another unplanned caving event in a nearby stope, 740D. As a direct result of these unplanned failures it was decided to mine the stopes with a smaller span than had been previously planned and in a primary-secondary pyramidal stoping sequence. To limit the exposure of the stope hangingwall, a hangingwall drive is no longer developed and therefore geologists no longer have access to the detailed geological information that this provided. Geologists at George Fisher Mine have had to be adaptable and flexible in response to these proposed changes and rely more on data from drilling than mapping for their geological interpretation. The result is that the drilling cycle has become much more critical in the planning process.

Jan 1, 2003