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Geological. engineering is a field of engineering practice concerned with design and construction of excavations and structures in soil and rock masses. The role of geological engineering in mining practice is defined in this paper, and the scope of the various disciplines in engineering science and geoscience which support geo-engineering research is discussed. The current national research capacity in geo-engineering is considered, and current and future needs for geo-engineering research for mining practice are proposed. Education programmes to sustain the proposed level of research and its industrial implementation are Suggested.

Jan 1, 1986

By R. Raymond

The occurrence and distribution of organic sulfur in coals may be investigated using electron probe microanalysis, scanning electron microscopy, and optical petrography. A general relationship exists between macerals and organic sulfur contents in individual coals: sporinite, resinite = micrinite, vitrinite > pseudovitrinite = semifusinite = macrinite > fusinite. With increasing organic sulfur content of a coal, the total range in organic sulfur content between macerals containing high and low organic sulfur contents likewise increases. Furthermore, the organic sulfur content of the vitrinite in most coals equals the organic sulfur content of the coal. For any individual coal, organic sulfur contents of macerals correlate inversely with reflectance-in-oil measurements, but the amount the organic sulfur contents vary between macerals cannot be calculated based solely on the coal's rank. Formation of pyrite following peatification has no effect on organic sulfur contents of surrounding macerals.

Jan 1, 1986

By K. R. Wood, G. W. McDonald

"The tailings disposal system at Les Mines Selbaie includes dewatering of tailings in a high-capacity thickener, followed by point discharge of the thickened solids to form a stable conical pile. Tailings water drains to ponds formed behind engineered dams, prior to either recycling f or process use or discharge to the environment. Design and economic considerations of the system are discussed. Construction, start-up and operating experiences are also presented.Introduction Les Mines Selbaie is located in the Abitibi region of northwestern Quebec, approximately 700 km north of Toronto and 150km south of James Bay. More locally, the Detour gold mine is 60 km to the west while the Noranda smelter is 220 km to the south.The deposit was discovered as a result of a Questor INPUT Mark VI geophysical survey in 1973, followed by diamond drill programs from 1974 to 1976. Three mineralized zones were delineated and underground exploration was carried out on all three. A production decision for the 'B-zone' copper-gold-silver orebody was made in July 1979. The underground operation started in July 1981, with full production of 1500 t/d being achieved in May 1982.During the planning phase, every effort was made to ensure that the operation would be environmentally sound . The design included the provisions of the then newly proposed provincial environmental guidelines. The tailings disposal system formed the most significant part of the environmental program due to the large volumes of solids and water effluent. In addition, the design allowed for future expansion of the system to accommodate mining of the other zones, thus minimizing future costs and disruptions."

Jan 1, 1986

By A. V. Castelli

Since the record year of 1981 through 1985 the tonnage of weighting materials (barite and other heavy minerals) used in drilling fluids has decreased an estimated 49%. As in the past, barite still makes up over 90% of the minerals used for weighting materials in drilling fluid. Domestic production of barite has decreased 69% since 1981 and imported barite has made up over 50% of the total barite consumed since 1982. See Figure 1 for usage of barite. The number of operating grinding plants has decreased from 69 in 1982 to 39 at the end of 1985. With the decrease in demand of weighting materials for drilling fluids and an over capacity of grinding existing, prices for weighting materials have decreased dramatically. Although the American Petroleum Institute has not changed any of the specifications for barite, some users have initiated their own new specifications and have proposed to have them included in the API specifications. The exploration for and development of oil and gas dictates the level of weighting material used in the drilling fluids industry. Most forecasters do not foresee (or predict) increases in the level of drilling until the 90's. The primary or unground barite produced in the U.S. mines has a difficult time competing with imported barite due to the location of the mines. These mines are located in North Central Nevada, with small tonnages being produced in California, Missouri, Illinois, Montana and Washington. The major reason, is the difference in transportation costs from the mines versus ocean freight rates from the foreign ports to the major area of use, the U.S. Gulf. Since 1981, the production of primary barite has decreased from 2,849,000/ST (2,584,596/MT) in 1981 to an estimated 890,000/ ST (807,403/MT) in 1985(1). If it were not for the use of unit trains by some producers the production of primary barite in the U.S. would have probably declined another 20% in 1985. During the same period, of the total amount of barite consumed in the U.S., imported barite ore increased from 417, in 1981 to 65% in 1985. The major exporting countries to the U.S. during this period were China 46.27, Morocco 15.27., Chile 10%, Peru 8.4%, India 7.9%, Mexico 5.4%, Thailand 3.9% and Ireland 2.3%.

Jan 1, 1986

By Armstrong ME

The gas bubble energy generated by an explosive plays a major part. in the fragmentation, muckpile movement and damage produced. Previously, the interaction between gas pressure and the rock has been interpreted from a theoretical basis or a qualitative study of breakage mechanisms. A method to measure the fluctuations in gas pressure in rock adjacent to the blast has been developed. This peak pressure will vary with structure, as well as with distance and explosive type. The technique is simple to apply and can be used to observe the flow rate of gas at. varying distances. The apparent velocity of penetration is an indication of whether gas has travelled through pre-existing or blast induced cracks. The technique provides a ?n:eans of determining the suitability of an explosive for a given rock type, depending on the amount of displacement desired. The technique has application in optimir.irig throw blasting and predicting and controlling damage, particularly in highly structured rock masses.

Jan 1, 1986

The Queensland Department of Mines believes it is in the best interests of the gold mining industry to reduce and control the environmental impacts from gold mining since that is the community expectation.The Department of Mines has set as a special condition of many recently granted Mining Leases the requirement to submit a "Description of Operations" for the approval of the Minister, prior to commencing initial mining operations. In order to facilitate compliance by lessees with this condition an explanation is given of the reasons for this condition and how it is intended to achieve the objective of environmental protection.Environmental impact is operations dependent. Impact on a lease will vary quite significantly with the scale and methods employed. Before a lease can be granted and mined it is therefore necessary to have this information. The parameters of operations most critical both in terms of environment impact and economic viability are worked out and agreed with the lessee before the lease is granted. An approved description of operations which is required now, prior to the start of mining, provides the details of that agreement for the security and benefit of the lessee and the inspectors. It also provides the details of operations and environmental controls which were not required prior to the grant of the lease but are nevertheless required and necessary for compliance with the environmental standards.

Jan 1, 1986

By J. A. Herbst, L. B. Hales, R. Zaragoza

INTRODUCTION The Control Problem The need for automatic control in flotation plants stems from frequent and randomly occurring disturbances to the feed slurry. Typical disturbances occur in the solids feedrate, the slurry percent sol ids, and the mineralogy and flotability of the gangue and valuable minerals. In plants where semi -autogenous grinding mills (SAG) are used, feedrate changes are very large and changes in feed percent solids of 1m or more are common. Mineralogy changes between valuable minerals are common, as are changes in the host gangue rock. As these changes occur, the operator can attempt to compensate for them by making adjustments to the flotation cell levels, the dosage rates of the collectors and frothers, the pH, and in some cases the aeration rate of the cells. This problem is sometimes complicated by the fact that different sections of the flotation plant will be processing different ore types at the same time. Potential Savings with Control Flotation control brings about savings or plant improvements in two areas; the first is in improved metallurgy and the second is in reagent savings. Improved metallurgy includes increases in the average plant recovery and achieves target concentrate grade level s more consistently. Average recovery increases between 1.0 and 5.0 percentage points have been widely reported (Paakkinen, 1979; Sutherland, 1984). Reagent savings of up to 40 percent have also been reported (Hales, 1985). VARIABLES OF IMPORTANCE Control led, Manipulated, and Disturbance Variables The initial step in the analysis of the flotation control problem is identification of important variables which can affect the efficiency of separation. The efficiency of separation is represented by a group of controlled variables which can quantify the performance of a flotation circuit. This group includes variables such as grade, recovery, tonnage through- put, and circulating loads. The efficiency of separation of a flotation circuit may generally be defined by a grade recovery map, where each point on this map re- presents a set of operating conditions (see Figure 1). However, the combination of operating conditions must be set to operate close to the economic optimum. The group of operating variables which are changed in order to achieve desired circuit performance are called manipulated variables and can be classified into two

Jan 1, 1986

By Lumley G, Rowlands D

The overburden slusher (OS) is proposed as a stripping tool that is expected to find application in overburden stripping operations including open cut coal and oil shale mines. OS is expected to combat the effects of increasing depth on the productivity of conventional dragline stripping.Although previously developed stripping techniques have included the use of drag scrapers the OS is sufficiently different as to constitute a new stripping method.A study undertaken at the University of Queensland during 1985 is believed to be the first major study on the use of the OS and preliminary economic results are very encouraging. It appears that the OS has the capacity to remove overburden at a cheaper unit cost than the equivalent powered dragline stripping machine at any comparable depth of overburden. The OS is not adversely affected by increasing stripping depth to the same extent as a dragline. In addition, the action of the OS machine allows for the lowering of spoil face angles, thereby reducing spoil slope stability problems encountered in deep open cut strip mines.

Jan 1, 1986

By W. E. Webb

This report describes a method the Bureau of Mines devised for measuring the dielectric constant and loss tangent of low-loss minerals at microwave frequencies. Determina-tion of these properties makes it possible to predict the effects of using microwave heating in potential mineral processing applications. The method uses a test cell and radio-frequency (RF) impedance analyzer with automated data acquisition and analysis. In this initial phase of microwave heating research, the Bureau measured dielectric constants and loss tangents at frequencies between 100 MHz and 1 GHz. The objective was to establish a reliable data base for use in predicting the effects of microwave heating on minerals. Comparison with previously measured data showed the Bureau's measurement method to be accurate to within ± 3 pct. This report describes the method and discusses the preliminary results of the Bureau's investigations. Typical comparative data are included.

Jan 1, 1986

Comalco Limited has recently completed construction of a $50 million kaolin plant at the site of its bauxite mining and industrial minerals operation at Weipa. The plant will produce 100,000 tonnes per annum of coating grade kaolin for the paper industry. Comalco produced the first coating kaolin from the deposit in 1979 on a trial basis. Since then a variety of quality coating grades with specific particle size distributions and brightness values have been prepared. Extensive drilling and bulk sampling of the deposit over eight years has shown that the ore body is large and of a high grade suitable for the production of premium quality coating kaolins. The processing plant technology was developed by Comalco in association with the European kaolin and equipment producer Amberger Kaolinwerke GmbH (AKW). The Weipa kaolin plant is the first of this size to be built in the Pacific Basin region and it will offer the region's paper-coating mills a stable and reliable source of high-quality kaolin, shipped from an established bulk loading port. The paper provides an overview of the development of the kaolin investment the nature of the production process and details the

Jan 1, 1986

BHP Minerals Ltd operates an open cut iron ore mining operation on Koolan Island, off the coast north of Derby in the Kimberley region of Western Australia. The mine comprises a number of pits, the largest of which is situated adjacent to the coast on the southern side of the island. The lowest bench is currently at RL +2 m, and the mine has planned ultimate depth of RL -82 m. Mining has already extended below the pre-existing water table level, and below mean sea level. In 1984, an extensive program of drilling, geophysics and test pumping was instigated to evaluate the aquifer hydraulic properties and the nature of the groundwater flow regime. With the aid of computer modelling, predictions have been made of the likely dewatering and depressurization requirements, and a conceptual pumping and drainage system has been designed.

Jan 1, 1986

LANDSAT imagery has renewed interest in linear features first recognised by E. S. Hills in a physiographic model of Australia. Certain of these lineaments are aligned with structures which control mineralisation.Lineament guidelines are potentially useful in many poorlyexposed areas if they can be recognised early enough in exploration and drilling programs leading to mine development.A case history based on the Charters Towers Gold Field indicates that lineament guidelines can be established early enough to guide development ofnew mines. The position of the Charters Towers Lineament was known as early as 1956. Subsequently, more detailed publications identified and classified associated lineaments which provide intersections correlated with gold occurrences. The discovery of a significant orebody at one of the most prominent lineament intersections came in 1975. Mine drilling has confirmed the influence ofintersecting structural trends indicated by lineaments but not by previous regional mapping.Recent gold discoveries south of Charters Towers lie in a grid of prominent lineaments. The development of mines about Charters Towers will provide additional understanding of relationships between centres of mineralisation and lineament intersections. This understanding may in future be sufficient to encourage exploration for a new generation of concealed gold deposits in northeastern Queensland.

Jan 1, 1986

The success of any industry depends on the planned integration of the policies and resources of the key components of the Australian economic and political structure - government, industry management, education, research, and the human resources of the industry. The Australian Mineral Industry, like Australia itself, has grown and developed at a rate not foreseen by many of our founding fathers and early industry leaders. Hence, now, as we approach the 21st Century, we need to re-think our approach to the significant new problems that are beginning to face both government and the Mineral Industry. Government initiatives, government information and support services, industry re-structuring, and research and development support, need to be carefully re-evaluated, re-diredted,. and strengthened, so that government, the community, and the Mineral Industry produce and receive the optimum education and research strategies and services. The support of academics and researchers, the development of facilities, and the design of new Courses for the future successful and beneficial exploitation of minerals need particular consideration.

Jan 1, 1986

By F. C. Lendrum

"This paper had its origin in a panel discussion organized by the Canadian Uranium Producers Metallurgical Committee (CUPMC) at their Annual Meeting in Blind River in May, 1964. The reason for the panel was the formation of the National Uranium Tailings Research Program funded in the amount of ten million dollars by the Federal government. According to the bureaucrats in charge the program would seek to solve the perceived problems as well as any actual problems they believed existed with uranium tailings. Dr. Allan Ashbrook of Eldorado Nuclear chaired this panel and his summation of the panel's purpose was set out as ""Regulation and the Regulatory Process in the Nuclear Industry, Where Have We Been, Where Are We Now and Where Are We Going""?"" This paper will try to relate these questions to the whole mineral industry.The Canadian Mining Association has been telling us our natural resources are today required only if they are competitively priced with those produced in so called ""third world"" countries where labour rates are lower, environmental restrictions may be less and every effort is made by the local government to sell their product. It is in this hostile economic climate that the Canadian mining industry now finds itself. Before going further I want to stress these comments apply only to: a) Mines financed by private capital in a free enterprise society.b) Mining companies want to operate in an environmentally safe manner. However, they must earn a profit because no company financed with private capital can borrow money ad infinitum.WHERE HAVE WE BEENNone of us today would want to return to the days when the mill waste management system consisted of pumping the tailing to the nearest slope and letting nature's law of gravity do the rest. This was the way it was in early gold mines in Nova Scotia, tin mines in Cornwall, England or silver mines in Cobalt, Ontario and survives today in countries where climate, customs and methods of doing business are far different from Canada. As mill tonnage rates increased, more sophisticated systems evolved often designed for mining areas with different climates. Systems imported from arid climates such as south-west United States retained the solids but allowed bacterial oxidation of the sulphides promoting acid drainage. Environmental regulations were introduced and Canadian mines learned to handle tailings in our climates."

Jan 1, 1986

By A. G. Galaitsis

This report summarizes the work performed under the USBM Contract No. J0245001. The purpose of this work was to expand and improve the scope and accuracy of the method developed under USBM Contract No. J0113056 for the prediction of the number of overexposed workers in the mining industry. A significant portion of the noise data were acquired during mine visits-that took place in the-course of this contract. These data were obtained with time-resolved dosimeters which among other things store a time history of the sampled noise for an eight hour work period. The remainder of the noise data have been obtained from MSHA files and from other BoM-sponsored projects. The report reviews the prediction model, discusses the model's assumptions and approximations, describes the function of the developed software, offers typical examples on the use of the software and includes plots of the newly acquired noise data records.

Jan 1, 1986

By Donald Christofferson

This report documents the program conducted to demonstrate the application of a flywheel-powered propulsion system to underground mining shuttle cars. Such application can replace the present electrical trailing cable common to most shuttle cars and thereby eliminate those safety hazards, maintenance problems, and haulage route limitations inherent in the trailing cable. Described are the activities undertaken to specify and design a flywheel of optimum size, shape, and material; to identify the best concepts of input and output systems; and to achieve installation of the power package into a shuttle car. The resultant Flywheel-Powered Shuttle Car is an FMC Model 6L shuttle car, 6-ton capacity, 20-ton gross vehicle weight, powered by a flywheel system with 4.5-kilowatt-hour usable energy. The completed vehicle was delivered to the Bureau of Mines in Bruceton, Pennsylvania, for testing and evaluation.

Jan 1, 1986

By L. A. Eros

The U.S. Bureau of Mines and Western Fuels Utah, Inc. entered into an agreement to plan, install, and evaluate a micro-computer based monitoring and control system at Deserado Mine, an underground coal mine. The U.S. Bureau of Hines contracted the Colorado School of Mines (CSN) to independently evaluate the project. CSM evaluated and documented costs, benefits, problems, and management and labor perceptions in this report. Recommendations are provided for mine operators and monitoring system vendors considering future installations.

Jan 1, 1986

By D. I. Bleiwas

The Bureau of Mines determined demonstrated tin resources and costs associated with tin production in order to evaluate the potential for tin production from 18 market economy countries (MEC's). Data were collected from tin producers, in most cases during on-site visits. The analyses evaluated the relative economic and resource position of 146 mines, deposits, or regions in January 1984 dollars. The demonstrated resource of recoverable tin within the nations studied is approximately 2.8 million metric tons (mt). Of this total, over 73 pct is recoverable from the Southeast Asian countries of Malaysia, Thailand, and Indonesia, which in 1983 accounted for almost 60 pct of the world's tin production. Brazil has joined the Southeast Asian countries as a major low-cost, high-volume supplier of tin and is likely to continue to expand its production. Given the 1984 market structure, over 60 pct of the tin in demonstrated resources was economically recoverable. Historically, the International Tin Council (ITC) has helped maintain relatively stable tin prices through a buffer stock and sales quotas. In late 1985, exhaustion of buffer stock funds led to suspension of tin trading on the world's major tin metal exchanges.

Jan 1, 1986

By Dale R. Ralston, Roy E. Williams, Gerry V. Winter, George L. Bloomsburg

GENERAL STATEMENT The primary objectives of any field data gath¬ering effort should be to (1) identify and gather the data necessary for the project and (2) obtain the data in a state-of-the-art manner. All too often the initial field data are collected both areally and tem¬porally in an illogical manner without the guidance of a conceptual model of the ground water flow systems involved or even a review of existing geo¬logic literature on the area of interest. The initial data collected frequently are of limited value while necessary basic reconnaissance information is miss¬ing. Initial field data should be collected with the intent of developing a hydrologic overview of the potential mine site and surrounding area. Ob¬viously, one of the initial objectives is to define the area requiring a hydrologic investigation. The data requirements should be identified by the time frame in which collection should be made and by the corresponding increase in sophistication of the data requirements with development and operation of the mine. The data requirements are summarized in Table 1. INITIAL LEVEL SITE INVESTIGATION Area Determination The initial task of any hydrogeologic investi¬gation is to determine the boundaries of the area requiring study. Obviously, the site of the proposed mine is included in the study area. The areal extent beyond the site may be determined from an eval¬uation of existing geologic and topographic maps. Those formations that overlie the ore body, the formations containing the ore body, and the formation(s) that lies immediately beneath the ore body are of direct concern for proper site recon¬naissance. Additional formations below the ore body may require study depending upon their thick¬ness, hydraulic conductivity, and degree of inter¬connection with the mine workings. This initial viewpoint identifies hydrostratigraphic units based strictly on geologic concepts such as mineralogy and structure. Formation outcrops, synclines, an¬ticlines, faults, and fracture and joint patterns are used to delineate the area of the site reconnaissance. The simplistic hydrogeologic environment (il¬lustrated in Fig. 3, chapter 2) requires that field data be collected via test wells and/or geophysical techniques. This approach is necessitated by the lack of surface features such as formation outcrops, streams, and springs. Fig. 5 (chapter 2) illustrates a slightly more complex hydrogeologic regime. The potential mine sites at locations A, B, C, D, and E each intercept a different ground water flow sys¬tem or combination of flow systems. Therefore, each mine location requires that a different area and size of area be investigated. A more complex geologic setting as illustrated in Figs. 6 and 7 (chapter 2) may be approached differently. The area included for the site recon¬naissance should encompass sufficient surrounding area to include the outcrops of those formations suspected of being influenced by the future mine. Even adjacent areas not suspected of being influ¬enced may be investigated if the formations of in¬terest crop out in those areas. Such an extension of the area of investigation would provide a greater regional understanding of the hydrogeologic properties of the formations (hydrostratigraphic units) of interest. Geologic Investigation The initial step before conducting the site re¬connaissance is to review all existing literature on the geology of the area. Existing information should be augmented with new exploration data on the dip, strike, thickness, and lateral extent of the for¬mations in the area. Exploration hole logs should be reviewed for indications of lost circulation, rub¬ble zones, and water producing zones. Existing aer¬ial photos such as those available from the US Department of the Interior, EROS Data Center,

Jan 1, 1986

By Both R. A, Daily B

The Patawarta Diapir, located in the northern Flinders Ranges (South Australia), has intruded into late Proterozoic Wilpena Group sedimentary rocks. The diapir contains disrupted blocks of a wide variety of rock types, most of which can be correlated with the Lower Callanna Beds of Willouran age, in a matrix of predominantly carbonate and siltstone breccia. Mafic rocks in the diapir appear to predate intrusion of the diapir. As with many other diapirs in the Flinders Ranges, copper mineralization is present in the diapir and occurs as narrow veins consisting essentially of carbonate with chalcopyrite and pyrite that formed after diapiric intrusion.Fluid inclusion studies demonstrate that the mineralizing fluid was a Na-Ca-K-Cl brine; probably derived by expulsion of interstitial water following emplacement of the diapir, with dissolution of evaporites within the Callanna Beds sediments and enrichment in copper by reaction with these sediments and associated basic igneous rocks. Mineral assemblages combined with fluid inclusion and geochemical data indicate a possible environment of vein formation of T ÿ 165°C, pH ÿ 4.3 ± 0.9 and log fO2 ÿ -47.3 ± 0.5. Sulphur isotope analyses indicate d34Sfluid ÿ 10 per mil, suggesting evaporites in the Proterozoic sediments as the major source of the sulphur but with some additional sulphur from an igneous source, possibly leached from the malic rocks of the diapir.

Jan 1, 1986