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By M Rankin, F Medina, R Verburg

We conducted a preliminary assessment of an extensive deposit of historic tailings discharged over a period of 40 years to the shoreline along a Southern Peruvian coastline. The tailings formed an extensive beach approximately 2.4 km long and 300 m wide. The tailings consist principally of pyrite (37 to 59 per cent), hematite (nine to 20 per cent), magnetite (three to 13 per cent) and quartz (11 to 36 per cent). The present operating company was required to evaluate the feasibility of capping the ocean side tailings deposit, however, given the size of the undertaking and the potential to reclaim residual minerals from the tailings, it was prudent to first evaluate whether capping would in fact reduce the impacts to the marine environment. Therefore this preliminary assessment examined: 1. metals contamination in tailings, shoreline porewater and marine sediments; 2. reactivity of tailings and acid generation potential; and 3. the potential for biological effects from metal contamination in the uplands tailings (solid phase) and beach porewater. Based on mineralogy, column leach studies and chemical results, the upland tailings have a high geochemical potential to acidify and release metals, especially copper, nickel and zinc, should they be subject to oxygenated and aqueous conditions. But, the extreme arid climate results in very low potential for precipitation and virtually precludes the transport of acid drainage reaction products from the upland tailings towards ocean. Wind erosion caused by offshore winds is likely a small source of tailing transport to the ocean. Since some potential exists to reprocess the tailings in the future, capping does not seem justified at present.

Jan 1, 2003

Fleet management systems have been adopted by many open pit mines throughout the world and the resulting improvement in truck cycle times has been one of the most significant contributors to mine efficiency. Ongoing enhancements to fleet management systems such as interfaces for vital signs monitoring have given incremental efficiency gains. Each incremental improvement is another step towards a grand vision of a totally automated mine. A relatively new fleet management system is being integrated with two other technologies to provide a highly reliable platform for a networked information system which monitors mine machinery and production. The paper reviews the integration project, the features of the new mine site information network platform and the contribution to productivity and safety. The new fleet management system has a predictive truck dispatch algorithm. It also has a distributed database that replicates rapidly so that each machine in the fleet has an identical database, thereby making each machine aware of other machinesÆ locations on the site. High precision systems for navigating and monitoring machinery such as drills, dozers, draglines and shovels provide individual machine operators with cockpit style real-time information to increase their operational efficiency. The integration of the new fleet management systems capabilities with the high precision systems that provide production information, machine vital signs data and operator information means that the mine operations and maintenance managers have real-time access to the whole mine siteÆs production data. Such a mine monitoring and reporting system is dependent on reliable wireless communications and reliable positions. Positions in fleet management and high precision systems for open pit mines are usually provided by global positioning system (GPS). Other global navigation satellite systems (GNSS) such as Glonass, and in the future Galileo, will provide additional satellite cover; however, some parts of open pit mines do not have enough sky visibility for reliable GNSS positioning and so a new centimetre level wireless positioning system called Locata is being integrated with the fleet and high precision systems to augment and backup the GNSS positions. The final integrated system will provide the highest levels of reliable position-based information to all stakeholders in a mineÆs operation, ensuring gains in productivity and safety.

Jan 1, 2008

The exploration industry generally has a low opinion of the quality of the service supplied to it by government departments. In particular, the academic research-related emphasis of the Bureau of Mineral Resources (BMR) and the relatively low level of explora- tion assistance offered by several Mines Departments are of concern. In a number of areas of geoscience research, the industry perceives a mixup of priorities and a lack of understanding on the part of governments as to its needs. While government's sights are, and should be, set on the future needs of the community at large, the industry doubts that government budget allocations to the BMR and Mines Departments are either large enough or being cost-effectively spent. This is certainly the case for such areas as exploration assist- ance, provision of basic exploration data, and applied geoscientific research. On balance, the exploration industry's perceptions are misguided in a number of respects because of a lack of communication with government. However, this reinforces the need for changes in the manner in which govern- ment departments communicate with industry and, in particular, the criteria upon which research priorities are based. At a time of contracting oil and mineral exploration expenditure, and near-record levels of geoscientist unemployment, the government's role is critical and should be open to question.

Jan 1, 1986

This paper examines the reform of mining legislation over recent years, the establishment of new Crown land management agencies, and the role of the Crown and environmental groups in nature conservation in New Zealand. It describes the relationship of the minerals industry to the Department of Conservation and environmental groups over recent years, and the prospects for mineral development on the Conservation Estate in future.

Jan 1, 1995

DuPont is a chemical and energy multi-national of approximately 90,000 employees. Often regarded as the world leader in injury reduction and process safety management, DuPont operate 140 manufacturing sites around the globe. Conoco is a wholly owed subsidiary of DuPont which is involved in oil, gas and coal exploration.   Throughout this paper I will discuss DuPont statistics, developing a safety culture and training process as well as discussing possible short comings in the New Zealand safety focus. I will conclude with my recommended improvements and issues for New Zealand companies to focus on.   It is very difficult to compare DuPont and New Zealand statistics through lack of compatibility in recording methods and my ability to interpret ACC's Injury Statistics. However through considering DuPont's statistics, and comparing them to your own companies or departments, you will agree they are indeed impressive. I hope that by discussing DuPont's safety philosophy, and possible shortfalls within New Zealand Legislation many of you will find ideas and inspiration which will help you to further reduce your own injury rates.

Jan 1, 1997

In current mining practices it is desirable to bring about a substantial increase in both rate of face advance and productivity, thus compelling the mine engineer to consider better and more productive ways of mining. Transportation plays a vital role in achieving improved productivity. This paper focuses on horizontal transportation systems. Horizontal transportation is defined from the shaft station area to the end of the stope cross-cut. Traditionally, horizontal transportation is inefficient in comparison to vertical transportation efficiencies and accounts for a high proportion of South African mine accidents. Thus, the role of horizontal transportation has been investigated in detail, as it offers the greatest chance for improvement. The purpose of the paper is to provide a best practice guideline for the design of horizontal underground transport systems. It is intended that the document be used by mine designers and planners as an aide memoir during the design process and benefit may well be gained from retrofit and reorganisation activity. The paper looks at transport systems suitable for deep level gold mining in South Africa and evaluates such items as management, scheduling, and haulage systems. Current transportation systems for personnel, material and rock transportation are evaluated, gaps in technology highlighted, and recommendations made.

Jan 1, 2003

By S Pollak, A Amon

This paper describes the current and finished design work which has been performed for shallow rock station caverns for New York CityÆs first new subway construction in 60 years. A new robust, sophisticated, design procedure has been developed for two up to 30 m wide caverns, with overburden of less then 12 m, and rock cover to span ratios (C/S) in the order of 0.25. The design is based on empirical input parameters like the Q-value, rock mass rating (RMR) values, rock mass class after Cording (1984), cover to span ratios, which have been validated by the use of structural computer models as well as two- and three-dimensional numerical discontinuum models. The design approach is a staged approach using first principles, empirical models and non-linear FEM and DEM models. In addition, the paper describes the factors and circumstances why shallow caverns have been selected instead of cut-and-cover structures and why all the underground station structures have been developed as drained structures.

Jan 1, 2008

By D H MACKENZIE

In common with several great orebodies and mineral camps around the world Broken Hill has been the subject of state-of-the-art technical and scientific scrutiny during its long working life. During the early years geological interest in Broken Hill tended to be directed at the body for its intrinsic scientific worth, mainly on account of its large size, high grade and wealth of mineral species. For much of the last 60 years the interest has had a more applied motivation, namely, to assist the search for either repetitions in the Broken Hill field or analogues in other terrains. This paper looks at the major changes in geological concepts and exploration techniques applied at Broken Hill and attempts to assess their impact.

Jan 1, 1992

New Zealand's obligations under Kyoto protocol New Zealand's economic and emissions profile Use of energy and electricity generation in New Zealand World energy supply Coal's rule in the world today Coal and New Zealand Future energy needs in New Zealand Clean coal technologies

Jan 1, 2002

FOR some time it has been recognised by the Metallurgical Staff that the presence of pyrite in the ore was adversely affecting the grades of the flotation concentrates.Following experimental work, it was decided to change over from the acid circuit in the mill to an alkaline circuit. The following description sets out the procedure adopted, -and the results obtained when such change-over was made.The Zinc Corporation ore consists mainly of galena, marmatite, calcite, and quartz, with smaller quantities of pyrite, fluorspar, and rhodonite.A clean specimen of marmatite picked from the ore assayed 53.4% zinc, and 10% iron, with no lead or insoluble. However, as zinc concentrates have been, at times, produced in the plant assaying over 53% zinc, and with only 8.7% iron, apparently the picked specimen of marmatite did not represent an average composition.The average would probltbly be between 8 and 9% of iron, and from 53.5 to 54.5% of zinc. It is obvious, therefore, that from this ore it is not possible to produce zinc concentrate of a higher grade than this average figure.In the Colorado School of Mines Quarterly for April, 1928, Vol. 23, No. 2, on page 47, we find the following statement:As the zinc in the ore exists as marmatite, which contains approximately 54.5% zinc and 10% iron, 49% zinc in the concentrate may be considered high.This statement refers to the ore treated in the Sullivan concentrator, owned by the Consolidated Mining and Smelting Company of Canada Limited.

Jan 1, 1930

By Watt KL

Chemical anchors for use in rock bolting have been produced in Australia under licence for several years. These anchors are alternatives to the more normally used mechanical anchors and give improved anchorage strengths under some conditions, although at greater cost. Considerable development during this time has resulted in an improved sausage-type chemical anchor more competitive in price, to such an extent that its use is increasing markedly. Particular-improvements allow load application up to the strength of the bolt within 2 min, reduction in cost, self-extinguishing features in the resin, improvements in manufacturing techniques, and an improved water- insensitive casing. At the same time, smaller bolt sizes have allowed reduction in resin volumes with consequent cost reduction. At this stage several aspects remain to be improved, particularly specialty anchors for specific purposes and Packaging.

Jan 1, 1971

By Glenn R. J

Treatment processes are outlined for the recovery of rutile and zircon from the heavy mineral-bearing sands on the east coast of Australia. With the exhaustion of the higher grade deposits and the imposition of more rigid specifications for the finished products, strict metallurgical control has become necessary.A description is given of the methods used by The Titanium Alloy Manufacturing Co. Pty. Limited to control the operation of suction dredging, of wet concentration using fans and spirals, and of dry separation using high tension and electromagnetic processes. By applying these methods a plant designed for an output of 15,000 tons of rutile per year has been tuned to produce over 20,000 tons of rutile and a corresponding amount of zircon.Details are given of (a) the method of drilling to determine the extent and grade of the ore bodies, (b) a simple electrically-timed pneumatic automatic sampler, and (c) the methods developed for the physical estimation of quartz, rutile, zircon, ilmenite and "others" in the products of plant operation.The method used for calculating the metallurgical balance and the forms used for the reporting of production results are presented.Examples are given which show the value of this detailed production and metallurgical control of plant operation.INTRODUCTIONThe organization which is now known as "The Titanium Alloy Manufacturing Co. Pty. Limited" (T.A.M.Co.)-a subsidiary of National Lead Company-commenced operating at Yamba, N.S.W., in 1935. A mixed natural concentrate was at first simply dried and bagged and later was upgraded by the removal of silica and the lighter heavy minerals on shaking tables and, after air-drying, was bagged for export. At that time zircon was the most wanted constituent.

Jan 1, 1960

By T P. Tafirenyika, K C. Corin, C T. O’Connor

There is a growing demand for copper driven by its applications in renewable energy and electric vehicles. Sulfide ores are an important source of copper. Flotation is a critical front-end process used to remove gangue minerals and concentrate the copper minerals. The electrochemical activity of sulfide minerals contributes to their overall activity in the flotation pulp. The mineral rest potential dictates how collectors interact with the mineral surface, and hence ultimately on the flotation response. Dissolved oxygen, (DO), pH, redox potential (Eh) and water composition and ionic strength are also significant in controlling flotation performance. The aim of this investigation was to determine the influence of the electrochemical environment both during milling and flotation on the flotation behaviour of bornite and chalcocite. For this investigation, the interactions of collector with bornite and chalcocite were studied using synthetic plant water (SPW1) and deionised water (DIW) at 5 different pH levels. Sodium isobutyl xanthate (SIBX) was used both in microflotation, collector adsorption and zeta potential tests.

Aug 24, 2022

By Brouwer G, Shaw J

As South African gold mines go deeper, and improved and more uniform working condi- tions are required, ever larger amounts of refrigeration are needed. At the same time new and more suitable cooling equipment is becoming available for use with new mining layouts as well as on existing shaft systems. The advent of the large diameter rotor screw compressor has meant that there is now a machine available with great flexibility in performance and construction for efficient underground use. The first installation using this type of machine is described.

Jan 1, 1988

The output of Dexin Pit Copper is up to 33 million tonnes a year and the final depth is more than 500 m. As a cost reduction measure, the in-pit crushing and conveying system has was introduced to deliver ore from the pit to mills. This paper describes the in-pit crushing and conveying system, and highlights the optimum level where the shovel-truck haulage system transfers into In-pit Crushing and Conveying system, relocation of an in-pit crushing system, and includes the impact of the transferring point when the costs change.

Jan 1, 2003

By Runge IC

The mine planning process is reviewed and appropriate software considered in terms of "line process" or "support function". The mine planner's requirements of a geological model and the elements of and requirements of a computerised mine planning system are all discussed. The use of "support" software for mine planning is considered and general rules for its development are given. Important changes involved in implementing a computerised mine planning program are listed.

Jan 1, 1983

The reality is that in today's world almost half of nearly six billion people on the planet do not have access to commercial energy and the services it brings. Based on UN projections, in 30 years time there are likely to be nearly three billion more people in the world, over 90 per cent of them in countries which are already economically poor. The World Energy Council (WEC), through its 102 member countries, monitors trends and developments and projects future trends. WEC is a non-governmental international body representing all forms of energy and is committed to the sustainable use of energy for all mankind. This paper is based on WEC studies and papers presented at its many conferences and congresses worldwide. Primary energy demand growth is dominated by the developing countries over the next 30 years. The world energy mix is projected to change very little over the next 30 years. Fossil fuel supplies (ie coal, oil and gas) are likely to decline from 77 per cent to 73 per cent, nuclear energy may grow from five per cent to six per cent and renewable energy sources (eg hydro, solar, geothermal, wind, tidal and biomass) could increase from 18 per cent to 21 per cent. World energy consumption is expected to grow by over 50 per cent over the next 30 years. The paper reviews changes in energy demand in the world, particularly in the Asia/Pacific region. Environmental issues are covered, as are developments such as solar energy from space and the status of renewable energy forms. Agendas for action to achieve change are also reviewed.

Jan 1, 1997

Iron and steelmaking slags have been utilised for a century. All dumps are now exhausted. Because of constraints in establishing new stock yards, all slags have to be utilised immediately. At present, this is being achieved. Only in a situation where there is an increase in pig iron and crude steel production, together with the impact of new residual materials competing from other industries can marketing problems be anticipated.

Jan 1, 1979

This address is set deliberately in the broadest possible terms. A review of the place of mining in Australian life today will serve to point up the changes that we can see in the life of people in the industry. Some of the influences on the future welfare of mining people bear also on the progress of this Institute, now approaching its 90th year. As mining becomes more and more dependent on higher technology and therefore, on the higher skills of the people in the industry, the role of The Institute, I suggest, becomes more and more significant.With investment per employee in mining generally continuing to rise, our ability to handle problems of manpower and human relations becomes a matter of greater importance.Questions that flow from these general thoughts form the substance of what I have to say.

Jan 1, 1982

By Mirabediny H, Whitchurch K

A computerised simulation model has been developed to select the most suitable digging method of a dragline operation for a given geological condition. The developed procedure uses a geological ore body model as the basis for the geologic database. The simulation selects the most cost effective dragline digging method from a database of various dragline digging methods The database consists of common and innovative dragline methods currently used in Australian open cut mines. A generalised computer package, DSLX, was extensively used to simulate various dragline digging methods. The DSLX software uses predefined functions to build strip geometry, working benches, blast profiles and spoil piles. The outputs from DSLX in form of volumetric, swing angles and hoist distances data are then aggregated with dragline specifications and site time study data to compare productivity of selected digging methods. The result of a case study showed that this procedure lends itself to the 'optimum' selection a dragline digging method for a given coal deposit.

Jan 1, 1995