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With the proclamation of the Environmental Protection Act, 1971-80, the Environmental Protection Authority and Department of Conser- vation and Environment were established to enhance the quality of the environment. Proposed gold developments of all scales can be referred to the Authority in the form of a Notice of Intent. Environmentally significant projects might then require preparation of an Environmental Review and Management Programme. Current environmental issues include the'effects of clearing by prospectors,, mine dewatering and tailings disposal. INTRODUCTION In the past, the environmental aspects of gold industry related activities have received little attention. However, with the proclamation of the Environmental Protection Act, 1971-80, mechanisms were instituted which allowed both for referral of projects to the Environmental Protection Authority (EPA) and establishment of the Department of Conservation and Environment. As well as providing assistance to the EPA on referred projects, the Department is concerned about a number of environmental issues associated with the gold mining industry.

Jan 1, 1982

A brief descri;tioki is given of nuclear power reactors and their fuels. These fuels are made from a variety of uranium compounds such as uranium dioxide, and uranium carbide as well as uranium metal and its alloys. The various processes used to produce some of these compounds from yellow cake are outlined. Using the natural uranium, heavy water reactor by way of illustration, fabrication of fuel elements is dis- cussed and the characteristics of U02 powder required for this partic- ular fabrication are indicated. The flowsheets and equipment presently in use overseas for production of this type of U02 powder are described. Possible areas where improvements might be made to this conventional process are enumerated and some details are then given of the programme of work which has commenced at the A.A.E.C. Research Establishment to gain experience in the general field of nuclear grade UO20

Jan 1, 1968

By Stump NW

Until a year ago all isotope on-stream analysis utilised flow cells similar to those designed for conventional X-ray on-stream analysis. These systems incorporated a fairly complex sampling system necessary to present a representa- tive air-free sample of the main process to the flow cell. Maintenance costs and capital costs associated with flow cells and sampling systems have been generally high. Costs can be greatly reduced and reliability greatly increased, by using isotopes incorporated in immersible on-stream analysis probes which actually dip into the main process stream eliminating the need for sampling. A bonus of other advantages associated with immersible probes includes temperature stability and ease of calibration. This paper discusses details and results of the probe systems, justifica- tion for installing on-stream analysis, comparison of conventional X-ray and isotope techniques, and a brief survey of methods of analysis using radio- isotopes in on-stream elemental determinations.

Jan 1, 1971

Mining projects frequently fail to meet their financial objectives. A significant area of poor performance lies in the areas of resource estimation, reserve definitions, selective mining and metal accounting. The processes leading to the exploi

Jan 1, 1998

By Bebb G

This paper describes the use of SURPAC, a survey/mine planning software package as used at Central Norseman Gold. It details the basic operating principles of the package, the applications in which it is employed, and its time and cost benefits and efficiencies as they apply to the above operations, both surface and underground.

Jan 1, 1985

By Musa MA

Tunnel excavation for sewer construction long remained a labour intensive, hazardous and costly operation. Even with the of mechanical and semi-mechanical shields for tunnel excavation, many problems remained until recently. In the past decade, however, the technology has changed dramatically which has made possible the use of advanced tunnelling methods for sewer construction.

Jan 1, 1993

Adsorption isotherms, zeta potential and coagulation techniques have been used to exa- mine the mechanism of metal activation on SiO2 and ZnS surfaces. The importance of surface nucleation or precipitation of metal hydroxide coatings is'established and identified-by characteristic charge reversal patterns. The significance of surface coatings in sulphide and non-sulphide flotation is discussed.

Jan 1, 1973

By Matthews SM, Gooding JE

N Longhole Open Stope at The Zinc Corporation Mine was developed in an area with large and continuous tension cracks. These cracks resulted fran widespread block subsidence into previously mined areas. The practical problems encountered and their solutions are discussed together with an outline of a new method of stope wall support using large diameter dowels installed sub-parallel to the stope wall.

Jan 1, 1985

By Turner W. G, Trundle R. S, Medland D. G

Contracting has evolved from basically a tradesman providing a service for an `employer' to a multi disciplined organisation providing an all compassing service for a client.Having commenced its activities as Thiess Bros Pty Ltd, providing simple earthmoving services in rural Queensland, Thiess Contractors Pty Ltd which provides a wide range of services for Governments and Industry is used as an example of an experienced multi-disciplined Contractor.

Jan 1, 1992

By King ND

This paper presents an economic study comparing two gold recovery processes, zinc precipitation (Merrill-Crowe) and carbon-in-pulp (CIP). Capital, operating, and gold losses costs from an actual CIP plant study are compared to costs developed from a hypothetical Merrill-Crowe process flowsheet. ' Results indicate an overall economic advantage to CIP over Merrill-Crowe for plants processing slurries within the range of the five gold solution grades selected for this study.

Jan 1, 1982

By Moore A. J

Control of blast vibration requires that its nature and causes be understood, and that effective control procedures be implemented to ensure compliance with limits related to the probability of damage to buildings/structures and human discomfort. This paper covers measurement equipment, assessment and prediction techniques, blast vibration control procedures and applicable statutory limits. It reviews current practice, and provides information on recent developments in blast vibration measurement equipment and control techniques, using examples based on Hunter Valley mining practice.

Jan 1, 1995

By Luke K. A

Pressure on production at New Zealand China Clays has led to the development of a dewatering control loop for fine halloysite china clay. The development was based on the analysis of data from the automation of plate and frame filter presses. The analysis of the data has led to process changes, and the ability to quickly solve dewatering problems. As a result of control in the dewatering circuit press times have reduced on average 117% and output has increased proportionally.

Jan 1, 1989

By Gostylla W

The economic feasibility of controlled district cross-cut recirculation is examined in this paper with particular reference to the most important mine ventilation network parameters. An algorithm is developed to express the annual cost of recirculation which is then compared to the annual cost of conventional ventilation using the University of Queensland Experimental Mine as a case study. The concepts of resistance ratio and volumetric efficiency ratio are introduced and used to analyse the economic feasibility of controlled recirculation within a mine ventilation network.

Jan 1, 1988

By Hollis R. G, Tuppurainen J. M I

Improved control of non-ferrous sintering operations requires the on-line measurement of sinter quality. No on-line measure of sinter quality is currently available, however, previous work has shown that the raw mix chemistry and peak sintering temperature determine the mineral phases formed and hence the resulting Blast Furnace behaviour. Control of these factors should therefore lead to improved quality control. In this paper, the development of a simplified heat and mass balance model of the Sinter Plant at Mt Isa is described. The model used available plant data to calculate raw mix composition and a simplified reaction scheme to predict sinter composition. The extent of reaction is inferred from the flue gas analyses. Off-line testing of a dynamic version demonstrated that actual plant performance could be predicted with reasonable accuracy.

Jan 1, 1989

The æProfit Driver ModelÆ is a tool which builds costs from first principles and integrates revenue, costs and physical mining parameters and, hence, can quantify the impact and leverage on profit. In this paper an æexample mineÆ has been created to represent a typical Australian Open Cut Coal Mine. This has then been input into the Profit Driver Model to allow different variables to be tested. A series of variables were tested to determine which ones had the highest impact on profit and results are useful to management as a guide to the areas in which they can focus effort to achieve better profitability. Whilst the highest profit drivers are those external to the control of management and include selling price and exchange rate, the next most sensitive are those variables related to the geology of the mine and the mining method. These included coal quality, yield and strip ratio. Site management has some control of these. For example, the ability to vary the sequence of mining or improve the yield by a more efficient coal washing process. The efficiency of the workforce and management has similar impact to the mining variables. Finally, there are the supply variables, such as fuel, labour and explosives which are the least sensitive although, cumulatively, still significant. Each mine is different and the results of the example mine will not apply to all mines. However, the approach taken is universal and the tool illustrates a simple method to quantify the profit impact when changing variables. The benefit of the approach is the short time taken to get a set of results. This allows the more detailed and time consuming work to be more focused. The results illustrate that management has a significant influence on profitability.

Jan 1, 2000

By Goode RA

It is-assumed that a pipeline system is economically justified as a means of transportation.. The terms "True Life" and "Economic Design Life" are defined. The most usual design alternatives to be considered from both physical and economic -viewpoints are listed and a summary is given of the main factors to be costed in assessing the relative economics of each alternative. A brief statement of the recor mended method af economic. assessment is given and an example is included. The paper aims to present a reasonably accurate, simple and practical method of considering the main economic factors which govern design.

Jan 1, 1962

The project is undertaken by Elgas Pty Ltd, a 50 per cent joint venture between AGL and BOC, to store 65 000 t of LPG in underground storage at Port Botany, NSW. The contractor, Concrete Constructions Pty Ltd, elected to use drilling and blasting techniques. The project specification called for the following works to be excavated: Access Shaft:122 m (out of 140 m total depth), 6.0 m diameter (selected by the contractor),Operation Shaft:125 m (out of 150 m total depth), 4.0 m diameter,Water Curtain Gallery:500 m (Later extended by additional 270 m), 4.0 m wide and 3.5 m high,Storage Caverns:910 m, 14.0 m wide, 11.0 m high,Top Heading:14.0 m wide, 5.5 m high,Bench:14.0 m wide, 5.5 m high,Connection Galleries:250 m, 5.5 m wide, 5.5 m high.A total of 156 000 cubm of rock to be excavated.

Jan 1, 1999

Wire rope, when used for hoisting on a mine is the weak- est and most vulnerable unit in the most expensive'-group of installations or! the mine. With the introduction' of hoisting on the S1Koepe"' sheave, a new technique was-established. This innovation brought with it the certain- advantages which long had been recognised and which are being developed further. For many years, drum winders of many types had been the sole means by which ore had been hauled from mines. This type of winder, with its capacity for rope storage on the drum, permitted mine operating personnel to cut short lengths from

Jan 1, 1964

By Thompson J

A programme of testing and evaluation has been in progress at Isa Mine for the last four years with the objectives of rationalising ground support practices, improving installation quality and increasing productivity of ground support functions.Numerous innovations have been successfully implemented. These include the introduction of swellex rockbolts as the major form of temporary support, the use of splitset rockbolts as the primary means of support for the hangingwalls of cut and fill stopes and the introduction of dowels with pumped cement for general long term support.The installation of swellex bolts has been successfully mechanised throughout the mine using Tamrock automatic rockbolters and Atlas Copco BUK 11R drilling rigs modified for this purpose.

Jan 1, 1985

Chemicals derived from petroleum raw materials satisfy so much of our industrial needs today that it is good to pause and realise two things -ò the petroleum chemical industry is so new, and the use of chemicals is a very old one.Petroleum is such an'abundant and convenient source of raw material that in little more than 30 years it has become the major source of supplyfor chemical rdanuf ctiree This paperw~l'l 'disc'uss t1.e main 'r`easons' for this rapid development by considering the : sub jest -under tkzree headings ea. Source of Raw Materials.b. The Impact of Petroleum Chemicals on Plant Design and Processes. ce Scme of the Major Chemicals Used Today.

Jan 1, 1962