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By McConachie W. J

Introduction.Ore Bodies.Lead.Copper.Ground.Main Haulage Levels.Stope Preparation.Stoping Practice.General.Longitudinal Stopes-Ring Drilled.Parallel Hole Drilled.Transverse Stopes -Ring Drilled.Parallel Hole Drilled.Charging and Wiring.Fragmentation.Pillar Recovery.Special Applications of Blast Holes.General Drilling Data.Future Trends.Acknowledgements.INTRODUCTIONThe purpose of this paper is to present a detailed account of current blast hole stoping practice at Mount Isa. Details of blast hole machines, types of diamond bits and performances are covered in B. E. Logan's paper "Diamond Drills and Bits".ORE BODIESThis brief description is limited to an outline of the salient features of the Black Star lead and copper bodies.

Jan 1, 1953

By Nyamekye GA, Subramanian S

Adsorption tests have been carried out to elucidate the interaction mechanism between dextrin and sulphide minerals. Sulphides such as galena and heazlewoodite exhibit high affinity adsorption over the pH range that coincides with the iep of lead and nickel hydroxides, and is suggestive of chemical interaction. The adsorption behaviour with respect to the sulphides of copper is of the low affinity type, and follows a different pattern. The adsorption studies on graphite, support the chemical interaction mechanism, with the metallic impurities serving as adsorption centres. In conformity with the proposed mechanism selective separation of galena from chalcopyrite and heazlewoodite from chalcocite has been Achieved.

Jan 1, 1993

Prediction of fragmentation in Taconite Mining is an important aid to blasting engineers. A simple theory relates the intensity of radial fracture per unit length to distance from the borehole, from which a power law for mass fraction passing versus size is derived. For the lower end of the size distribution, the equation agrees well with several published examples of fragmentation from sieving of full scale blasts. Large size fragments arise from interaction of fractures from neighboring holes and pre-existing joints. Analysis of two assumptions regarding radial fracture interaction shows that complex fragmentation distributions can arise from the simple mechanisms proposed. Measured fragmentation falls between the two extremes calculated.

Jan 1, 1996

By Fabio Amaya, Andrés Marulanda, Ramiro Gutiérrez, Alberto Marulanda

The behavior of a salt rock mass is strongly related to a creep phenomenon. The amount of creep depends on the level of stress generated in the underground excavation. Additionally, security conditions and the lifespan of an underground cavern excavated under this geological conditions depend on the evolution of creep. Based on the experience of the failure of the Old Underground Salt Cathedral of Zipaquirá(Colombia) and the construction of the new one, the theoretical framework to predict the creep behavior of a salt rock mass is explained. The theoretical formulations are calibrated based on actual observations of the material behavior to predict the lifespan of this striking structure.

Jan 1, 2003

By John Nadolski

Intensive hydrologic monitoring of the Powder river basin has been on-going since the early 1970's. Data were used in environ- mental assessments and for determination of hydrologic consequences associated with coal mining activities. For most coal mine operators, data collection has continued in this baseline mode with little or no statistical analysis of the data and with no statistical procedure established to detect changes in groundwater quality. For the past four years Powder River Coal Company has studied several statistical techniques to analyze groundwater quality. Three objectives were pursued: 1) to determine the baseline water quality for key aquifers; 2) to determine which wells could be deleted from the monitoring program without reducing monitoring effectiveness; and 3) to define a statistical test to determine water quality changes. Knowledge of the regional geo-hydrologic system was combined with an analysis of the water quality monitoring in order to identify homogeneous aquifer zones. All wells within an aquifer zone were treated as one population, and a t-test was used to determine the minimum number of samples needed to define the water quality for each aquifer zone. Results indicate that the data for each aquifer zone were nor- mally distributed and that groundwater quality could be defined using a fairly small number of samples. Because of the minimum sample size test, groundwater quality sampling was reduced by between 75 and 85 percent.

Jan 1, 1989

By Ray Schmidt

When your committee approached me for a talk on "Mechanics of Secondary Metals Collection," I replied that this subject would probably not be very interesting to a group of engineers and requested permission to dwell on the Westinghouse Salvage Setup. I will attempt to avoid duplicating the points covered by Mr. Bliven. The Westinghouse Electric and Manufacturing Co. has main manufacturing Divisions in 25 cities and 9 different states, scattered throughout the country, as well as Naval Ordnance Plants in two midwest cities, and a Merchant Marine Turbine Plant, and two special War Production Plants in Eastern cities. You can, therefore, see that we must have a well rounded pro- gram with the entire respect and sponsorship of the various Division Managements. That was not so easy to get. Management has been a great deal like the general public in the past. I am sure most of you can remember the not very ancient day when each town had a ragman who had a horse and wagon and went through the streets of the town, from door to door, picking up what scrap he could accumulate. He was known as a junk man, and indeed, with the exception of the very last few years, the attitude of manufacturing management was: "We have a job to do. We have a product to manufacture. We don't have time to bother with the junk business."

Jan 1, 1943

By R. A. Jankowski, R. Gong, R. Bhaskar

The control of respirable coal dust in continuous mining sections involves careful analyses of the generation and transport of the dust, including airflow pattern analyses. Potential dust control devices must be evaluated based on their effect on both local dust transport and potential dust exposure of face personnel. The development of larger and more productive continuous miners increases the need for research on dust control and improvement of visibility in the face area. Two studies relating to underboom dust control are discussed. The first study involved the valuation of potential underboom dust control techniques to reduce operator exposure to dust and determining the relationship between the positioning of exhaust ventilation and the exposure of face personnel as a function of face and operating variables. The study involved full-scale laboratory experiments using a state- of-the-art data acquisition system. The second study related to the use of foam under a continuous miner boom and its effect on silica concentration and respirable dust. The foam study was performed in a coal mine. The laboratory studies involved the fabrication of a full-scale test facility and development of a computer based data acquisition system. This was followed by baseline data collection, smoke trace tests, detailed performance testing of various underboom dust control measures and data analyses. The underground foam test involved the design and installation of the foam generation and delivery system, testing, and data evaluation. The results of the studies are summarized in this paper.

Jan 1, 1991

By F. N. Kissell

The US Bureau of Mines undertook a study of those factors influencing worker escape from an outby coal mine fire. The results of this investigation were two-fold. First, those factors affecting escape from a mine fire were defined, and second, the relationships between these factors were identified. Although the individual components had been studied before, little information was available on their interdependence. Fault tree analysis was used to evaluate the miner escape scenario. After constructing the fault tree, a two-phase analysis of the tree was conducted. During the first phase, the minimal cutsets of the fault tree were identified and ranked. These sets were the smallest sequence of events leading to fatalities during the fire. This ranking revealed that reduced evacuation delays, improved self-rescuer training, and improved stopping construction were important in controlling fatalities during escape from the mine fire. The second phase involved additional analyses of the fault tree. These evaluations were started by first determining occurrence probabilities for each event in the fault tree. Two types of sensitivity analyses were then conducted. The first analysis dealt with changes in event probabilities and their impact on the likelihood of fatalities. The final sensitivity analysis considered dramatic reductions in the probability of fire fatalities. This revealed what event probability values were necessary to reach this level. These results have revealed various remedial actions that could be used to improve the survivability of an outby mine fire.

Jan 1, 1990

By T. Mudder, K. Harvey

The objectives for closure of a hard rock mine include minimizing long term environmental liability, attaining regulatory compliance, and maintaining geotechnical stability, while closing as cost-effectively as possible. Proper planning for closure should come during the feasibility study, design and permitting phases, and during operations as updates. The lack of a proper or updated closure plan can result in severe environmental and economic consequences. Effective mine closure is the result of a combination of innovative concepts, long-term commitments, and multi-party cooperation. The purpose of this paper is to discuss concepts, commitments, and cooperation as they relate to an effective closure plan.

Jan 1, 1999

By Robert S. MacPhail, Bret G. Cousins

Many copper-bearing ores with associated gold use Sodium Isopropyl Xanthate (SIPX) as a flotation agent. In general, SIPX will float to some extent other minerals that may not be desirable, such as pyrite. FLEX 31 is a chemically enhanced SIPX product with many of the same properties as SIPX. But FLEX 31 has the ability to reject more pyrite from concentrates and improves copper recovery when using up to 50% less FLEX 31 than is required if using SIPX. Copper activated minerals such as sphalerite and arsenopyrite show increased recoveries as well using FLEX 31. Tests have been performed on copper/zinc ores and an arsenopyrite/pyrite ore.

Jan 1, 1995

By Tooth MA

Mining, metallurgical and engineering consultants have made a considerable contribution to mining industry development in Australia. Expertise has been developed locally to a high level during the last decade which has contributed to the success of many recent mining projects. The services available'cover the whole spectrum from the evaluation of ore reserves, through feasibility study and financial evaluation to design, project management and commissioning. Using these services effectively and economically is an objective which client and consultant both must pursue but which is not always achieved. This paper discusses some aspects of the use of consultants which the experience of the authors has shown to be of prime Importance

Jan 1, 1975

By T Iwadachi, T Fujisawa an, G R. Alvear

A large amount of Be2C and BeO is formed during the Cu-Be alloy production process, because beryllium is a highly reactive element. Carbide and oxide formation impairs the production yield and the quality of the Cu-Be alloy products, and therefore should be minimised. As a first step for solving these problems in the process, the following thermodynamic properties of the Cu-Be-C-O system were investigated. Based on the results, the equilibrium relations of the Cu-Be-C-O system were clarified and the operational conditions of the current Cu-Be alloy production process were also examined and discussed.

Jan 1, 2000

Robert Campbell Gemmell, assistant managing director of the Jackling allied porphyry mining properties in Utah, New Mexico, Arizona and Nevada, died suddenly on Oct. 25, of heart trouble, while traveling from Hurley, N. M., to Los Angeles. To shape justly even an outline of the brilliant career and uniquely charming personality of Mr; Gemmell is well-nigh impossible, and any effort so to do can but demonstrate the inadequacy of language to sound the depths of soul-stirring sentiments. To touch upon his more important work, and afford even a limited conception of his general worth and character, is all I can hope to do.

Jan 1, 1923

By Nick Warren

The problem considered is that of predicting rock physical properties from observations of the structure of the rock. The approach here departs from previous studies in that both the physical properties and structural features are taken as statistical data and the relations between them are cast as statistical functions. This approach I have termed a "quantitative petrostructure analysis". This Paper deals with two aspects of making such a study; parameterizing patterns of topographic features of rock, and characterizing variables to allow correlation studies to be carried out. The principle of a quantitative petrostructure analysis is outlined and illustrated using maps from two samples of Conway granite.

Jan 1, 1982

Robert Campbell Gemmell, assistant managing director of the Jackling allied porphyry mining properties in Utah, New Mexico, Arizona and Nevada, died suddenly on Oct. 25, of heart trouble, while traveling from Hurley, N. M., to Los Angeles. To shape justly even an outline of the brilliant career and uniquely charming personality of Mr; Gemmell is well-nigh impossible, and any effort so to do can but demonstrate the inadequacy of language to sound the depths of soul-stirring sentiments. To touch upon his more important work, and afford even a limited conception of his general worth and character, is all I can hope to do.

Jan 1, 1923

By Persifor Frazer

AMONG the geological problems with which the present Pennsylvania Geological Survey has had to deal is the relative age of a series of strata passing around and through the city of Philadelphia, Bucks, Chester, and Delaware counties. Rogers includes all these rocks in his hypozoic series, and every student, so far as the writer knows, with one exception, has assigned to them a position beneath the Potsdam sandstone, or " Primal " of that eminent and gifted geologist. So far as regards the small portions of this belt, to which it is the intention of the present paper to draw attention, even the one geolo - * Read at the Lake Superior Meeting, August, 1880.

Jan 1, 1881

By Bradford F. Townsend, Gary Peach, Roger Rothenburger

From the experience of the authors on recent large infrastructure Design-Build projects this paper reviews major lessons for Contractors and Owners in the delivery of large Design-Build infrastructure projects and some major pitfalls and warnings to both Owners and Contractors. The paper is written from both the Design and Construction perspective. A case history is presented that details the approach employed to ensure a quality project consistent from the initial design phase through construction and outlines the strategy used to guide the Design-Build process to an acceptable completion. Suggestions are made for Contractors and Owners for handling the Design and the Construction elements of Design-Build contracts.

Jan 1, 2003

By St. E. Deák

Mining activities involve excavation from underground to the surface of large quantities of ore (e.g. uranium and its disintegration products) (Dumitrescu, 2002, 2007). Material with limited content of uranium, deemed as sterile or low-radioactive is mainly stored on the surface. These wastes modify the configuration of the disposal areas and affect the quality of the environment and the landscape. This paper presents both analytical and numerical models related to stability assessment of uranium mining waste dumps. It is focused on the calibration procedure of the numerical models, in order to minimize risk error during stability prediction and avoid long term environment pollution.

Jan 1, 2008

By Kiyoshi Sugasawa

At Sumitomo Metal Industries, technologies for manufacturing metallurgical coke have been developed, under the names of Sumicoal System and DKS formed coke processes. Sumicoal System is the process utilizing approximately 70% conventional fine coal, 30% briquettes charge, and 2-3% caking substance. This technology was industrialized in 1975, and now the blending ratio of non-coking coal has reached up to 20%. On the other hand, a large scale demonstration plant using the DKS process was constructed and operated over one year. As the result of that test, it is thought that the DKS process has also reached the stage of industrialization. This paper will describe these new coking technologies.

Jan 1, 1977

By Fred D. Wright

In this paper the principal theories used to design roof bolting systems are presented and discussed. Then the characteristics of various types of roof bolts are presented and finally the interaction between rock and roof bolt characteristics on choice of roof bolts is discussed. Theories can be considered design tools which may or may not be appropriate for a specific situation. It is good for a design engineer to have a number of such tools available and also important that he understand their good features as well as their limitations. Hence, some of the principal theories and classification systems used for design of roof bolting systems are discussed first.

Jan 1, 1982