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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

By Rao A. B, Rao V. D

Northeast of Brazil is situated in the polygon of drought. It covers some very important states like Bahia,Pernam- buco, Paraiba, Rio Grande do Norte, Cea- ra and Piaui , which have a potential for mineral production. Of them the main contributions that comes from Rio Grande do Nor to , Ceara and Paraiba are the scheelite and im portant quantities of granitic pegmatite mine- rals like tantalite-columbites, micas, beryls, precious stones, lithium minerals etc. On the other hand flourishing mineral economy in gold, tin, emeralds, chromium, lead, apatite is most- ly from Bahia; and potassium, salts, and petro- leum are from Sergipe, Alagoas and Bahia res; pectively. The most interesting aspect coninues to be the nucleus of the drought zone constituted of the Rio Grande do Norte, Paraiba and Ceara sta- tes.The first two authors have worked for twel- ve years in the region and have dedicated atten tion and time to two systems, namely skarns and granitic pegmatites. Their mineralogy,petrogra- phy, geochemistry, origin and economy is being worked upon from time to time to accompany the progress that is being achieved both in the sec tors of geology and economy. Besides, during the field campaigns, evidences have been sought to find the best guide horizons for mineralisa- tion and options for the location of target areas and prospection methods for scheelite, tantalites and other pegmatite minerals.

Jan 1, 1988

By Lysnar R, Horswill M

Since the introduction of the pocket calculator, electronic measuring equipment, lasers and computers, the mine surveyor's approach to his work has changed. Where he once used steel bands he now uses infra-red, visible light or radio waves. The reading and storing of angles is done automatically and he now has to be familiar with the facilities that a computer can offer, instead of plotting and calculating manually. This highly sophisticated equipment is continually being upgraded, modified and fine tuned. This paper will attempt to highlight some of the equipment at present in use by the surveying profession and research currently being conducted by the WA School of Mines. The various options in EDM will be considered including the latest unit capable of measuring distance without the benefit of a reflector, thus enabling the surveyor to co-ordinate points that were previously thought inaccessible. The School is currently working on changes to the GAK1 Gyro Theodolite which may improve results and enable the operator to have more control and confidence in his observations. Areas under consideration are improved lighting, binocular viewing and interfacing the instrument to a stopwatch. In the last few years the computer is being used not only for surface pickups and control but also for underground work. We will highlight the underground options in this area and the software available.

Jan 1, 1987

The integration of historic exploration geoscientific data with high precision multi-element and isotope geochemistry can provide explorers fundamental information on mineral potentiality, tectonic setting, source signatures, fluid migration, mineralisation environment and the timing of mineralising events. Such knowledge is crucial for ore modelling and target generation, particularly for concealed ore systems in both brown and greenfields. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The new field of environmental investiga tions introduces new problems of ethics, res- ponsibility, conflict of interest and technical procedures. Such investigations involve four elements: developer, consultant, approving authority and the public. It is essential that the consultant provide technical competence, speed and efficiency, impartiality and credibi- lity. Despite allegations to the contrary, it is not in the consultant's own best interest to omit, ignore or obscure significant adverse en vironmental impacts.

Jan 1, 1975

By Kurzeme M, Willoughby D. R

The current approach to the design of fill, as a structural component in a mining system, is based on traditional usage, previous experience, empirical rules and preconceived ideas. This approach does not permit the relative economicsof the various possibilities to be evaluated, retards introduction of new materials or processes, and results in fragmented fill research effort.A rational approach to the design of fill is proposed as a means of overcoming these disadvantages.This is based on five components:(a) statement of functions of fill,(b) definition of modes of fill response,(c) criteria of satisfactory performance,(d) analysis of fill response,(e) specification of required fill properties and methods of obtaining them.An assessment of each component indicates that the adoption of this rational design approach will require research effort in categorising modes of fill response and in defining criteria of satisfactory performance.

Jan 1, 1973

There is little doubt that the vision (Spectre) of Voisey's Bay has completely spooked the Northern Hemisphere view on nickel to the exclusion of considering any other future nickel project. Voisey's Bay orebody is of world-class and will influence world nickel and cobalt supply for a very long time - but - has the world yet started to consider the enormous cost of acquisition and development of this find or the nickel price it will need to attract to cover these costs and its operating costs and keep its bankers and shareholders happy. That price will be the critical factor in determining Voisey's effect on world nickel and will be critical in ranking other new projects aimed at making up the nickel short fall created by the on-going demand for austenitic stainless steel. In my view, there is little doubt that some if not most of these `other' new projects will be developed in the South West Pacific from lateritic Resources.

Jan 1, 1996

By Atkinson D

This paper briefly outlines the develop ment of the froth flotation plant at Coal Cliff Colliery. The plant was superimposed onto the original flow sheet in which fines were merely thickened and filtered. Test work leading up to the installation is described and the final layout is discussed. Details of the concentrate and tailings systems are given. Preliminary results of a further extension involving the use of a Davcra flotation machine are also given.

Jan 1, 1974

By Huafu L, Ruishi N, Hongnian Y, Qinglong Z, Yangshen S

The Dongshan terrane was first recognized in 1984 (Guo,et al., 1984, 1989) as an old continental crust block of migmatized granitic gneiss in the Southeast Coastal Hercynian-Indosinian orogen, and it was thought to have occured on Dongshan Island, which has an area of less than 100 km? Recent research work has shed much light on the geology of the Dongshan terrane.The Dongshan terrane is approximately 40-50 km wide and 380 km long, trending NE. It runs from the region of the mouth of the Ming River through Putian and Huian Counties, Amoy and Dongshan island of Fujian Province to Nanao island of Guangdong Province, bordering the southern segment of the coastal region and coastal islands of Fujian and eastern tip of Guangdong Province. The Dongshan terrane is divided from the Zhejian-Fujian Mesozoic Volcanic Mountain Chains by the Changle-Shaoan fractural zone, and its eastern boundary is covered under water in the Taiwan Straits.

Jan 1, 1990

By R Gaze, J Horton

Block models generated with all linear interpolation algorithms contain inherent smoothing that typically results in an underestimation of grades and overestimation of tonnes in resource estimates. For mineral deposits that are anticipated to be exploited by underground mining methods excessive smoothing may result in materially misleading estimates of Ore Reserves. To account for smoothing in the open pit mining environment recoverable reserve techniques such as indicator kriging and uniform conditioning are employed to provide non-spatially located proportions of the large blocks above the cut-off grade. These models are not suitable for underground mine planning where the actual location of material above cut-off is required to design its extraction. To correct for excessive smoothing it is proposed to modify the ordinary kriged block estimates a posteriori using an affine correction with a local variance adjustment factor. The proposed methodology is demonstrated for a base metal deposit during a feasibility study.

Jan 1, 2009

By S A. Ravishankar

An overview of flotation reagents used in sulfide and non-sulfide separations, from an industrial perspective, is given in this presentation to highlight the current applications knowledge. The historical and theoretical aspects, which are well documented in numerous books and reviews, will only be highlighted, when necessary, to support the theme of this paper, viz critical analysis of reagent research, design, selection and optimisation with an emphasis on relevance to plant needs and practice. The three types of flotation reagents; viz collectors, frothers and modifiers, used currently in the industry are briefly reviewed; pitfalls and gaps, arising from somewhat arbitrary and reductionistic practice in reagent applications, are identified; and the impact of environmental regulations on current and future reagent development is discussed. The importance of frothers and modifiers, which have received less overall attention than collectors, is highlighted. The need for a rational, holistic (or ætotal systemÆ, ætop-downÆ) approach for reagent design, selection and optimisation is discussed with a view to provide remedies for pitfalls and a platform for filling gaps in reagent chemistry and applications, and to develop reagent technology that can deliver robust solutions to plant needs. Flotation Matrix 100TM, a comprehensive package designed at Cytec to incorporate all the elements of the holistic approach û viz definition of mineralogy and plant needs, rule-based expert system rational reagent selection, and laboratory and plant best practices û will also be described.No paper available for this abstract

Jan 1, 2005

It is self evident that in many cases mining disrupts communities, however, community reaction to mining varies enormously. This is due to a whole host of factors, some physical, some financial, some political and some a direct result of the projected mining company attitude towards the community at large. Physical and political factors are increasingly being dealt with realistically and financial aspects are to a significant extent determined by profit margins. If the acceptable profit margin canÆt accommodate all necessary costs (which now includes a variety of community considerations unheard of even a decade ago), then the project is just not viable. Despite major commitments now made by many mining companies to their affected communities, corporate attitudes, and their projection, remain as the most outstanding factor in mining project development where real gains can still be made in effectively reducing social risk. This paper addresses both international and domestic experience gained in managing this aspect of mining development risk, including initiatives implemented by multilateral institutions.

Jan 1, 2003

Mount Gibson Iron Limited (æMount Gibson IronÆ) has made the difficult transition from a privately owned company with an iron resource to a publicly listed company owning and operating a profitable iron ore mine in the mid-west of Western Australia. The development of the company is described with particular emphasis on the Tallering Peak operations, resources, associated infrastructure and logistical arrangements; the Mt Gibson hematite and magnetite resources and the proposals to develop the magnetite resource as part of an integrated project through to iron pellet production. The concept of tailoring the relatively small ship capacity of the outturn port of Geraldton to appropriately sized inturn ports in China to allow direct delivery of product is discussed. The companyÆs philosophy of building shareholder value by progressive development of its relatively modest resources (compared with the Pilbara) is discussed. In pursuit of long-term business success Mount Gibson Iron has formed symbiotic relationships with strong business partners whose aims and objectives mirror or complement those of Mount Gibson Iron.

Jan 1, 2005

As a society, the retiring age of workers is increasing. Individuals are having to consider working to an older age (beyond 55 years), the reason being to æpay offÆ debt, maintain a quality of life or, as a bigger picture, because society simply cannot afford the aging population. The Government is encouraging and promoting those approaching retirement to work to an older age to alleviate the financial burden of an aging population. In a working context those aged 55 years and over accounted for ten per cent of the Australian workforce in 1998 with this age group expected to account for half of the growth in the workforce between now and 2016. For the 60 - 64 years which account for less than three per cent in 1998, this group is expected to account for 15 per cent of the growth in the same period. As a result of individuals who have worked all their lives and in some cases æphysically hardÆ, they do not fully enjoy their years of retirement as a time when they get to choose what they want to do rather than what they have to do. Of particular interest are the physical or health related conditions that individuals end up with and the restrictions that ensue resulting in an individual being incapacitated either physically or with respect to the state of their health.

Jan 1, 2005

THE object of this note is to set forth some particulars of the effect of light on cinnabar occurring in a deposit of this mineral at Puhipubi, in the North Auckland peninsula of New Zealand. This deposit is contained within a gently-inclined sheet of siliceous sinter forminga hillock called Mount Mitchell, and is particularly notable in that it is an instance of the simultaneous deposition of cinnabar and silica on a large scale. The mercury-bearing material varies in character from semi-porous sinter to dense translucent cbalcedony, of which the former is stained to various shades of pink, the latter to brilliant reds and vermilion. On exposure to daylight-and particularly to sunlight - these colours change to corresponding shades of translucent bluish-grey. As a direct result of this change the Mount Mitchell deposit remained unknown until some ten years ago, for, while prospectors early discovered cinnabar in the adjacent city and in a neighbouring stream bed, none of them recognized this mineral in the bluish chalcedony strewing portions of the surface of the Mount. The writer has carried out a series of experiments designed to indicate the cause and nature of this change, and to form a basis for the elaboration of more delicate experiments which would yield positive information. Circumstances, however, have so far combined to prevent the continuation of the research, and, as there seems little prospect of the writer being able to do more work on the subject, it seems well to publish the data so far obtained. Prior to describing this colour change, the writer would point out the desirability of restricting the meaning of the term cinnabar to the naturally occurring red sulphide of mercury; this would eliminate the ambiguities which arise from its indiscriminate application, in chemical literature, to both natural and artificial sulphides. Further the term cinnabarite having long since fallen into disuse, there appears to be no good reason for retaining the companionterm "metacinnabarite" when reduction to "metacinnabar" would preserve the meaning in a less clumsy word.

Jan 1, 1923

By F

Ore reserve estimation has been described as the most individualistic, the most prickly and even the most controversial of all the technical aspects of the mining profession. This symposium is a great opportunity to look at the present state of the art and full marks must go to the Sydney Branch for organi- sing it at this time. The first essential of good ore esti- mation is probably an awareness of the uncertainties involved, and the possible impli- cations of these uncertainties.

Jan 1, 1979

The Greens are asking the question: what do our mining towns look like in 2050 and how can we be better prepared? The resources boom brought enormous profits to the main players and was partly responsible for insulating Australia through the worst of last year's global economic turmoil. However, with indicators of a resurgent mining boom, it is essential we learn from the recent past. The last boom saw housing stress at levels unseen in the big cities, health services strained to breaking point, and Aboriginal poverty side by side with some of the most lucrative industrial precincts in the country. Much of the wealth still flies right over the heads of regional communities as fly-in, fly-out operations proliferate.   Behind these local stresses, resources booms rely on the stripping of non-renewable resources which will eventually run out, and the unique environment of the north-west is taking a battering.    Communities of the north-west have a perilously narrow economic base which must be broadened if townships of the Pilbara and Goldfields are to avoid the fate of places such as Goldsworthy and Wittenoom. Unless this is informed by local communities, decisions will be made in capital cities thousands of kilometres away by people largely ignorant of the unique conditions prevailing in regional Western Australia.   Global climate change negotiations and oil depletion will heavily penalise emissions-intensive economies like Australia which fail to keep up as the world moves to a low-carbon environment. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

By Moxon NT

The detonation pressure of ANFO can be significantly reduced by the addition of low density materials such as polystyrene, bagasse, sawdust or perlite. Laboratory and field test results have shown that homogene- ous mixtures of these low density explosives can be produced in a bowl truck and loaded into a blast hole without segregation. The detonation pressure of the mixture can be tailored to suit the material to be blasted by varying the quantity of low density additive incorporated into the mix- ture. Results obtained in the field indicate that these low density explo- sives can lead to significant cost savings without compromising fragmentation or production.

Jan 1, 1988

By Windsor C

A review of the current pit design procedures and their performance has been undertaken recently by Mining Research Associates (MRA) and the CSIRO Division of Geomechanics. Visits were made to mines covering a wide range of operations. A questionnaire was completed by each mine in order to collate the relevant information. Interviews were also made with representatives of the Mines Departments to ascertain their role in regulating mine designs. Design expectations were compared with field performance, and reasons for variations noted. Problems associated with designs were identified and suggested methods of alleviating the problems have been made.

Jan 1, 1986

By Maru Y

The use of mercury for amalgamation has been an integral part of the small-scale gold mining industry in developing countries owing to its low investment cost, simplicity of the technique and high gold recovery. However, its impact on health and environmental hazards have not been given the attention they deserve. In spite of the growing awareness and concerns over the mercury pollution problem by regul-atory authorities, precautionary measures such as bans on the use of mercury in some countries have been largely ineffective.This paper first reviews some of the mechanisms of mercury poll-ution, and mercury toxicity which varies according to its oxidation state. It then describes how mercury released to the atmosphere would go through the "Mercury Cycle". Compar-isons have also been made with previously measured mercury levels in small scale Papua New Guinean miners with their counterparts in other developing countries.

Jan 1, 1994