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By A. Bothma

The Impala No. 1A ventilation shaft is located approximately 15 kms north of Rustenburg and is accessed via the R510road from Rustenburg to Northam/Thabazimbi. This situation is shown on the location plan in Figure 1. The geology at the site consists of an upper layer of black turf of about 1 metre in thickness, grading into weathered norite. The depth of weathering is generally less than 5 metres. Zones of deeper weathering may occur along fracture zones associated with faults and dykes. Groundwater occurs mainly within the weathered/fractured aquifer system. The ventilation shaft is a 5.1 m diameter upcast shaft ,and forms part of a system of ventilation shafts to complement the existing infrastructure as mining progresses down the new twin decline extension of Impala 1 shaft. The principal reason for these shafts is to lessen the risk of an extended RAW and also to counter the effects of the heat build-up as the mining goes deeper, with the resultant effect that the existing cooling centre (fridge plant) becomes more remote from activities. The No. 1A shaft (upcast) is positioned approximately 1,2 km on down dip from the main shaft and the No. 1Bshaft (downcast) approximately 1,2 km further. Geological information was used from a borehole 1,2 km away on strike from the upcast shaft. The first shaft (1A) is a 5,1 m diameter hole to be fitted with two 2,2 MW fans, whilst the second shaft (1B) is 4,1 m diameter to accommodate a 7MW fridge plant.

Jan 1, 2001

By Trevor Yeomans, David Yaschyshyn

"Placer Dome (CLA) operates the 90-year-old Dome Mine, in South Porcupine, Ontario.The milling operation currently processes 5 million tons of ore per year, from both the underground and Open pit mining operations, producing 320 000 ounces. The milling process is conventional crushing and grinding, with gold recovery by gravity followed by leach/CIP.Cyanide tailings are impounded in a large (325 ha) tailings area where cyanide is allowed to degrade naturally. Effluent is discharged seasonally during the summer and early fall months to maintain site water balance. Pond water is reclaimed for sole use within the mill process.In 1995, an Effluent Treatment Plant (ETP) was constructed for the purpose of removing dissolved metals and suspended solids. In 1997, an INCO S02/Air cyanide destruction module was added.During this time period, the treated effluent often failed toxicity tests required by the Ontario MISA Regulation, even though effluent chemical parameters were below permit limits. Two studies identified ammonia as the toxicant to Rainbow Trout, and free copper as the toxicant to Daphnia magna.From a literature study, and contacts within the Ontario Mining Association, the use of chelation as a final end of pipe treatment step to render any remaining free copper and metal fractions biologically unavailable was considered. Lab and plant scale tests followed.During the 1999 ETP operating season, the addition of the chelant EDTA (ethylene-diamine-tetraacetic-acid) commenced. To date discharged effluent has passed all toxicity tests.The paper will review the effluent treatment history, current effluent treatment plant operation, and detail the use of EDTA for successful toxicity control.History of Tailings Deposition, and Effluent Treatment From 1910 to 1995Over it’s ninety years of operation, the Dome Mine milling circuit has changed from the original 1910 stamp-mill mercury plant, to today’s modem 14 000 ton per day automated gravity and Carbon in Pulp based plant.By the 19803, a modern mill was operating on mainly underground mined ore. The plant was operating at some 3 800 tons per day, using fairly conventional processing routes.The number 4 tailings dam was being used for tailing’s deposition.All effluent treatment was by natural degradation of cyanide. Discharge was from decanting type structures during the summer months only, maximizing the use of natural degradation no tailings effluent was recycled for Mill use."

Jan 1, 2001

By Wilson Blake

Rock preconditioning in advance of mining was shown to be an effective means of rock-burst control based on the results of a field demonstration carried out on the 7700 level of the Hecla Mining Company's Star mine. Mining through the preconditioned zone was characterized by greatly reduced rates of released seismic energy and no bumping or rock bursting occurred within the preconditioned zone. Mining above the preconditioned zone was characterized by greatly increased rates of released seismic energy and rock bursting, particularly where the vein became very narrow in waste zones. This increased incidence of rock bursting points out the need for stope preconditioning to be carried out on an entire stope block basis. The data obtained from the monitoring of the mining above the preconditioned zone on the 7700 level will be extremely useful in evaluating any future stope block preconditioning experiments on the lower levels or the Star mine.

Jan 1, 1980

An optical computing system was used to determine spacings and frequencies in geological fabrics and engineering joint fabrics.Three-dimensional arrays of joints were plotted on an equal-area net. Directions in which true spacings are seen were determined from these plots. Photographs taken along these directions were used for optical computing.

Jan 1, 1970

By R. D. Currie

A study of the accident statistics in the coal mining industry convinces one that an organized effort must be put forth to prevent the vast destruction of human life in this industry . The fatality rate in Pennsylvania has not improved in the past several years and during 1928 it was higher than the average for the period 1916 to 1927 , inclusive . Although the accident rate for this State is less than that of the coal mines of the United States as a whole , nevertheless the rate is unduly high ; however , there are many companies which have exceptionally good records as regards both fatal and nonfatal accidents . A study of the methods used by some of these relatively good- record companies to reduce accidents in their mines shows that they exert an organized effort to prevent accidents , and that their safety organizations usually affect every employee in and about the mine from the highest official to the check boy . The chief executive must be actively and personally interested in accident prevention if real safety results are to be obtained ; when he shows this interest it is almost invariably reflected in the officials under him and throughout the organization . Safety organizations vary in form and are readily changed or adapted to the varying conditions found in the bituminous field . The companies whose organizations were studied in preparing this report are all getting good results , and it is their opinion that the safety organizations have been a big factor in obtaining these results . At their request the identity of some of the companies whose organizations were studied has not been divulged in this paper , but this does not affect the value of the information concerning their safety organizations .

Mar 1, 1931

By M. A. Elliott, H. H. Schrenk, L. G. Berger, John C. Holtz

"INTRODUCTION Interest in the possibility of using Diesel 6/ engines for haulage power in mining and tunneling is increasing in the United States, owing largely to the reported successful use of Diesel locomotives in European coal mines and to the comparatively recent development of automotive Diesel engines in this country. The extent of this interest has been evidenced to the Bureau of Mines by numerous requests for information as to the factors that must be considered if Diesel engines are to be used safely underground.Proponents of the application of the Diesel engine to underground haulage base their claims for its safety upon a comparison with the gasoline engine, assuming that (1) the carbon monoxide content of Diesel exhaust gas is always low and that (2) fire and explosion hazards from Diesel fuel are minimized because of its low volatility. In these respects the Diesel engine appears less hazardous than the gasoline engine, whose use underground has been discouraged by the Bureau of Mines and other organizations interested in safety in mining. However, such generalizations cannot be accepted as conclusive evidence that safety is inherent in Diesel engines in underground service, as European experience indicates that certain hazards may accompany their use. Such hazards were discussed in a previous publication 7/ that reviews developments in the use of Diesel locomotives in European coal mines.The Bureau of Mines has initiated a study of the hazards that may attend the use of Diesel engines underground to obtain first-hand information that may serve as a basis for recommending sale practices under conditions existing in the United States."

May 1, 1940

By Subrata Dutta

Sindesar Khurd Mine is situated in Rajasthan, India, and operated by Hindustan Zinc Ltd, under Vedanta Group. The base metal mine is high in reserves of Lead, Zinc and silver and has been producing since 2007 with initial production of 0.3 mtpa. Recently the mine has gained prominence as a base metal underground mine in introduction of latest mining techniques and achieving high production at lowest costs. The promising Lead-Zinc reserves of Sindesar Khurd Mine (SKM) and high-tech exploration adopted by Hindustan Zinc Ltd (HZL), (Vedanta Group), raising the reserves and resources from a meager 9 Mt (1997) to 81 Mt (2012), has prompted HZL management to ramp up the mine production from 0.3 mtpa (2006-07) to 2 mtpa by 2013-14 with ambitious plans to reach 3.5mtpa subsequently (presently largest underground metal mine in India). The complete trackless system underground mine, recently equipped with latest leaky feeder communication system (unique in India), utilize modern drilling, mucking and hauling equipment aided with various utility/service vehicles. Excavation optimization and quality recovery maximization from the open and post filled stoping methods, continual expert analysis and feedback from International consultants like AMC (Australia) and SRK (UK), and involvement of renowned bodies in management excellence, have lead the mine towards highest productivity and lowest mine operating cost, earning the mine a prominent place in the global base metal industry. The paper deals with how the various challenges in mine planning and designing, mine development, operator skill, equipment introduction and maintenance, expertise availability, provide training and exposure to officials, prompt and effective communication/service, control of ground vibrations, maintain ventilation standards etc are faced in attaining high operational excellence and thus attain a record mine output/man shift (OMS) of 14 ton/man shift with targets to reach 20 ton/man /shift. Scientific designing using 2D/3D numerical mine-modeling techniques, faster stope sequencing with introduction of paste filling ( first time in India),latest leaky feeder communication system, control ground vibration to stringent standards using electronic delay system, faster raising techniques using raise borers to enhance development and ventilation, cavity scanners to monitor large stope voids, fast shaft sinking at 100 m/month(Chinese expertise) and maintaining adequate ventilation with close software monitoring are some of the highlights discussed in the paper towards achieving the targets.

Aug 1, 2013

By Sh. Karimidorabati

In the construction industry, project changes constitute a major cause of delay, disruption, cost increases, poor quality and unsatisfying performance. They are also known as a main factor of litigation between the owners and constructors. Construction projects are essentially process-based, and with the critical role of Information Technology (IT) in this industry, projects, especially mega projects, are being managed remotely. The volume of data and documents, such as Requests For Information (RFIs), different types of Change Requests (CRs) and Project Change Notices (PCNs), being transferred and exchanged amongst the stakeholders of a project is considerable. The circulation of these documents amongst project stakeholders still heavily relies on two methods or levels for management of change process; Conventional (fully paper-based, Faxes, Snail mails) and Electronic or semi-automated (Email, Internet, PDF files). These two methods are dependent on human discipline to follow specified processes which often break down because of human nature. This creates serious compliance problems. It is hypothesized here that fully that automated process-based management of change can lead to better compliance, more efficient management of change, and reduction of time and cost of data exchange. An approach of doing this is presented in this paper. Ultimately, its impact should improve project performance. Conclusions are presented on time savings and improved compliance.

Aug 1, 2013

By R. J. Gunderman

Redesigns of the operator compartments on a continuous miner and on a face haulage vehicle are described. The objective was to optimize the compartments within limitations of existing equipment and functional configurations. Both safety and production should be improved through more comfort for the operator and more natural placement of controls. Design guidelines supplied by the Bureau from a previous contract were used along with human factors analyses to determine requirements. Mock-ups were fabricated from layouts and used to refine design details. The new compartments were implemented and the machines evaluated underground. Comments and reactions to both machines were favorable.

Jan 1, 1978

Thirty mixed cultures of microorganisms from soil, water and mineral samples from the Groote Eylandt Mining Company mine site were approximately three times more effective in biodegrading manganese dioxide (34± 18 mg Mn++/1/day) than sixteen purified strains (11 ± 10 mg Mn++/1/day) isolated from the primary enrichment cultures. Two pure bacterial genera identified as a Pseudomonad and a Bacillus, with an excess MnOz and nutrient, were able to dissolve 106 mg Mn++/litre/day in mixed culture compared with 29 mg Mn++/litre/day when grown separately.

Jan 1, 1983

By Edward J. Cording, William H. Hansmire

INTRODUCTION The Washington Metro, a rapid transit system that will serve the District of Columbia, Virginia, and Maryland, has been under construction for about two years. Construction of the Metro by the Washington Metropolitan Area Transit Authority involves a large amount of cut and cover, soil tunnel, and rock tunnel construction. To aid initial construction and improve future designs, performance observations were undertaken on tunnels in the initial construction phase. The University of Illinois Department of Civil Engineering was engaged to carry out a comprehensive program of field observations and measurements for this purpose. One part of the program was on the first soft ground tunnel constructed in the system. The tunnel is a 2200-ft (670 m) twin-bore section, designated Contract A-2, in downtown Washington. Two objectives of this program were to determine the relationship of construction procedure to settlements and to observe the pattern of soil movement around the tunnel as an aid in evaluating underpinning criteria for nearby structures. A test section, consisting t three instrument lines located across the tunnel path, was established prior to mining in Lafayette Park to measure in detail both vertical and lateral soil displacements as the tunnel was mined through the section. The site was selected because it is free from surface structures and access for installation and reading of the instruments was convenient. Load and distortion measurements on the lining were also made within the test section; observations of construction procedure were maintained throughout construction.

Jan 1, 1997

By Hugh Thompson

In mining today, planning is of paramount importance, even more so when one considers that the business margins are reducing, requiring the evaluation of diverse alternatives for the optimal use of scarce resources. Additionally the capital required to approve some projects demands the best planning possible. Modern planning requires that all of the aspects of the business be represented, and not just the planning of the extraction in an isolated form. In order to carry out integrated strategic planning in the mining business one needs to have implemented a culture within the organisation that allows the business to be understood as a interelated system of processes. These processes must be co-ordinated so that they interact properly between each other and so define an integrated plan that optimises the available resources and maximises the benefit to the company. This defined culture should consider the important variables of each activity within the processes, and its’ relevance to the strategic plan. In this sense, this paper shows an example of computer tools used in order to reach the described objectives.

Aug 25, 2002

Mining men and State officials in their efforts to make mining safer are confronted from time to time with various complicated questions. In recent gears these questions have tended to increase with the use of mechanical appliances. Twenty-five years ago electricity had been used but little in mires; today there is practically no other means of transmitting power employed in American mines, except that in metal mines compressed air is used, chiefly for drilling and for operating small portable hoists. In coal mines there has been a great increase in mechanization, which tends to concentrate the work of production in small areas and to increase the local difficulties of ventilation; also, it has intensified locally the hazard from coal dust as well as firedamp in bituminous and subbituminous mines. The answers to the questions that arise are not always obvious, as is shown by the fact that even able, experienced men differ in their opinions of the best, way to overcome a particular mining hazard. The difficulty of .solving the problems is also demonstrated by the varying provisions in mine-safety rules, both in official regulations and in the rules of those mining companies that are endeavoring to do more than follow the letter of the law. Such differences of opinion as to the best way of meeting a difficult situation are often found within the same mining organization, and, similarly, varying opinions are held by different members of the Bureau of Mines staff.

Jan 1, 1937

By S. J. Schatzel, J. D. Addis, V. Gangrade, L. L. Chasko, C. A. Hollerich

A ventilation study using tracer gas was conducted at a western US coal mine. The objective of the study was to evaluate the movement of longwall face air exchanges between the face and worked-out area and to document the presence or absence of face airflow pathways between these locations. The mine operator uses a bleederless longwall ventilation system with a back return and a blowing mine ventilation system. The study was conducted on an active panel and included both underground and surface monitoring sites. The study used sulfur hexafluoride (SF6) released as a slug on the longwall face and in the front of the gob inby the face. The velocity of the tracer gas movement in the gob was 0.019 m/s (3.7 fpm). The rate of movement for the overall tracer gas slug averaged about 0.0091 m/s (1.8 fpm). A separate tracer gas test initiated with the release of SF6 into the legs of the first shield showed the existence of more than one pathway of face air in the general direction from the headgate towards the tailgate corner. Maintaining adequate ventilation air on longwall faces is important for worker safety and for the dilution of methane emitted from the face and caved gob. A more detailed characterization of longwall system air and gas movement allows a mine to better assess its ventilation design for controlling gas on the face and in the gob.

By J. B. Gilliatt

The discovery of ore at Wabana was quickly followed by the mining of the ore beds where they outcropped in the land areas. The third phase, as at present carried out, consists of extensive submarine operations, which were commenced in 1908, by driving a pair of slopes out under Conception bay, opening. the mine for a distance of a mile and a half from the shore. Two other slopes, now driven just beyond the shore line, are being sunk to the submarine territory where, it is generally recognized, huge reserves of ore lie under the bay. The process of erosion of the land, the solution and re-disposition of its iron-bearing minerals in thick beds of ore have been considered elsewhere, but these bear small relation to the physical forces which have acted upon the ore-beds since the deposition of the strata. These physical changes are made manifest by jointing and cleavage and faulting. The discussion of these, the relation they bear to each other, and to the folding of the strata, is the purpose of this article. For the benefit of those who may not be familiar with the formation in which the ore occurs, I include a general summary of the geology of Be!! island and its environs; also a description of conditions that prevailed during the period of deposition, so that the reader may appreciate some of the later changes that took place during or subsequent to its emergence from the sea, and the folding or tilting of the strata to the position it now occupies.

Jan 1, 1924

By J. J. Dowd

1. The Pittsburgh bed is the most important bed in Ohio County, and virtually the entire production of coal in the county comes from this bed. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of-coal in place, are estimated at 365 million short tons as of January 1, 1954. Of this total, 356 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1955

By R. Patrick

As a unique South African organisation, CSIR: Division of Mining Technology (Miningtek) strives to support the mining industry by improving health, safety and productivity through developing, adapting and transferring technology. Considerable effort is currently directed towards the development of potential non-explosive mining methods with the potential to allow continuous mining in narrow reef conditions. Besides improving productivity, continuous mining results in concentrated mining which has a significant impact on reducing infrastructural costs. Impact Ripping and Water Pulse Rock Breaking have been tried on gold mines, whereas Activation, Mini-Disc? cutting and the Plasma Holemaker are currently being tested on platinum mines. The organisation?s many years of experience in novel rockbreaking, together with its world-wide collaborator network, has placed it in a unique position to assist the mining industry and manufacturers in developing and/or adapting existing technologies for application underground. Currently a range of technologies are being investigated, which have reached different stages of maturity. The main technologies under investigation are; - Impact ripper system - Water pulse rock breaking - Activated undercutting rollers - Mini disc cutters - Electric rock breaking

Oct 1, 2001

By R. E. Brewwe

"INTRODUCTION Anyone who has had frequent occasion to compare methods of analysis and testing as employed in European countries with those used in the United States has felt the need of a table or graph giving the relationship between the units of measurement of finely powdered materials. Most of the few published comparisons include only two series of sieves and often require tedious interpolations to adapt the data of one series to the series more familiar to the reader. To eliminate such deficiencies, the author hopes that the discussion and comparison of fine-series sieve sizes presented here will conserve the time of interested research workers.ACKNOWLEDGMENTSThe author is deeply indebted to Virginia B. Strathearn, scientific aide, for help in compiling the information from the literature and to W. A. Solvig, senior chemist, for valuable suggestions in preparing the manuscript.SQUARE-MESH-SIEVE SERIES OF DIFFERENT COUNTRIESSieving analyses of powdered materials have been placed on a comparable basis in different countries by the introduction and adoption of standard sieve-scale series. Series of wire-cloth square-mesh sieves in common I oratory and industrial use include: Institution of Mining and Metallurgy standard laboratory screens (I.M.M.); British Standards Institution standard for fine-mesh test sieves (B.S. or B.S.I.); Tyler standard sereer-scale sieves; United States standard sieve series; Deutsche Industrial-Nermen (DIN); and the standard control sieves of the Association Francaise de Normalisation (AFNOR). With the exception of the I.M.M. series in which the opening is equal to the diameter of the wire, the general proportions of the various series of sieves are similar. The size of British and American sieves is designated by the number of meshes or openings per linear inch or, more recently, by the number of microns per linear sieve opening. In a technical sense the word ""mesh"" is meaningless, unless the diameter of the wire is also given, so that the size of the opening can be determined. On the Continent sieves are designated either by the nunber of Mesh per linear centimeter or by the number of openings per square centimeter."

Jul 1, 1944

As a part of its overall wealth in fuel resources, the United States possesses large reserves of coal of ignite rank. According to recent estimates of the Federal Geological Survey (3, 5),l/ the assured lignite reserves of this country amount in total to over 463 billion tons, equivalent to 24 percent of our total national coal reserve on a tonnage basis and 15 percent on a heating-value basis. Distribution and relative amounts of United States coal and lignite reserves are indicated in figure 1. By far the largest proportion of our lignite reserves, over 95 percent is found in North Central States, principally in North Dakota, South Dakota, and Montana, in the vast coal-bearing structural grouping designated as the Fort Union formation. Of the remaining United States reserves, all but a fraction of 1 percent are found in a series of relatively scattered deposits in Texas.

Jan 1, 1954

By S McKinley, S Juras, E Uludag

More and more, today’s mining geologists are asked to identify and create 3D value domains for multidisciplinary usage: grade definition, geometallurgical performance and geotechnical characteristics, to name a few. Often, that domain shape is the result of an assumed or conjectured value as a surrogate to a set of conditions (eg kaolinite-rich, sericite alteration). Would it not be instead better to create the respective domain through identification of a consistent quantifiable geologically-based pattern as its basis?Critical to the identification of patterns is the transformation of 3D point data into a model by a method that uses few, if any, preselected thresholds. Too often we complicate the reviews of the modelled data by prejudging the value range of interest. And when we do revert to 2D views (ie sections and plans), we tend to only examine numbers or line traces. These hinder and obscure identification of geological patterns particularly in deposits of complex geology. Instead, these data should be looked at with minimal prejudgment and interrogated in 2D space by one of the best and most eye-catching display types: filled contour plots.Here we present two different processes that transform data with minimal preselection into formats that allow for pattern recognition by filled contour plots. These are: probability assisted constrained kriging (PACK) and multiple interval interpolant formation (Aranz Geo’s Leapfrog® software). The former creates a 3D model of probabilities on a threshold value; the latter creates numerous (=10), regularly-binned 3D interval interpolants. The results of each method are examined as filled contours over numerous sections or plans. Any distinct patterns are quickly discerned thereby readily identifying the best value to base the creation of a domain. These processes therefore provide a way to marry recent advances in software tools with what is supposed a geologist’s core skill: pattern recognition.CITATION:Juras, S, McKinley, S and Uludag, E, 2017. Pattern recognition in transformed data – the search for domain shapes in mine geology data, in Proceedings Tenth International Mining Geology Conference 2017, pp 37–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017