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By Jaan Kiusalaas

This report is a self-contained User Manual for a computer program called SPASID -- Subsidence Prediction and System Identification. The program has two primary functions: (i) Precalculation of ground movements due to underground mining operations using the influence function method; (ii) Computation of influence function and site parameters from measured displacements. SPASID is written in FORTRAN and consists of four modules: (i) Preprocessor Module that prepares and maintains surface and mine data bases; (ii) Subsidence Computation Module that predicts movements of the surface; (iii) System Identification Module which is used to calculate the optimal influence function parameters, and (iv) Postprocessor Module for generating graphic displays of subsidence data. The last module is somewhat machine dependent but has internal documentation to indicate potential changes. All of the modules may be run in either batch or interactive mode. The manual does not assume previous knowledge of the influence function method or programming competence.

Jan 1, 1983

By Brad H. A Brown, J Paul Tidman

To design a blast, one must give consideration to safety, economics, geometry, geology, production needs, and a variety of other requirements. To compare designs requires the time to develop alternatives, analyze, and then improve on them. A number of tools are available to assist with the first set of requirements, however they are poorly integrated. SHOTPlus is a program to improve the efficiency of blasting operations, by combining measurement and blast design tools, and offers the user the time and means to modify designs and explore alternatives.

Jan 1, 1997

By S. Don Brown

Between 1987 and 1988, the Bureau of Mines studied the mineral resources of the White River National Forest and part of the Arapaho National Forest to appraise the resources present and to determine the types of deposits, and their location, that could be mined economically if sufficient demand and metal prices existed. The study included a comprehensive literature search and a limited amount of field investigation of minerals and mining activity in and near the Forest. Mineral resource information indicates that in the Gore Range the area between Tennessee Pass and Gilman may contain large base-and precious-metal deposits, and could be the focus of exploration activity in the near future. The Breckenridge mining district was found to have a moderate to high likelihood for mineral exploration and possible development of gold. Recent exploration and minor development work has occurred in several other areas: Montezuma, Kokomo-Tenmile, and Upper Blue River districts, and portions of the Sawatch Range. Limestone, marble, sand and gravel, rock for crushed aggregate, and other industrial rocks have been recently mined or Quarried in the Forrest, and will likely be mined or quarried in the near future. Currently coal is being produced at one mine in the Forest, and extensive identified coal resources are located in the Forest. Parts of four known gas fields lie within the Forest west of Glenwood Springs; there is current production at one field.

Jan 1, 1990

By M. Craig Miller

As the trend continues in the U. S. toward inceased capital investment in longwall mining equipment and wider panels. the risk also increases for gotential financial and production loses due to undetected geologic anomalies. This paper describes how RIM Sm (Radio Imaging Method) is utilized in conjunction with more traditional exploration and interpretive methods to delineate fluvial channels. displacement faults and poor roof conditions in a Southeastern Ohio coal mine

Jan 1, 1990

By G. Goellner

The thick alluvial sand and gravel deposits along the base of the San Gabriel mountain range in Southern California area have been mined for construction aggregates for over 100 years. Encroachment of high-density urban populations in this area has led to concentrated mining in a handful of open pit mines with single production faces reaching up to 55 m (175 ft) in height, and long transportation distances from the pit to the processing plant. Aggregate producers have responded to these challenges by developing innovative mining systems which enable low-cost, full-face mining of the alluvial material, and low cost delivery of this material to the plant.

Jan 1, 2004

By G. Lyle

Since its inception CEMI (Centre for Excellence in Mining Innovation) has focused on facilitating innovative solutions to the mining industry in six strategic research areas; GeoRisk, ConstructMine, ValueMine, FindMine, SustainMine and MineTech (visit www.miningexcellence.ca for details). This paper focuses on CEMI?s largest project to date, Ventilation on Demand (VOD). Energy consumption in mines can account for upwards of 40% of a mines operating cost, with a significant portion of this been consumed by the ventilation requirements. VOD provides a significant opportunity to reduce overall mine ventilation requirements and subsequently energy costs, while potentially increasing mine productivity. CEMI is currently in year 2 of an assessment of VOD, focusing on the financial, physical and equipment viability of utilizing such systems in both new and existing mines. This two year program, to be completed by March 31, 2011, is designed to systematically assess such a system to determine if and when it could effectively be applied in underground mines. The paper will describe the process by which the project was initiated, the demonstration projects established to capture data, the means to interpret the data and the modelling developed to calibrate and predict ventilation system requirements.

Oct 1, 2010

By Wilson Bardales

El presente trabajo describe la experiencia de la Gestión de la Calidad en la Cía. Minera Poderosa S.A., específicamente en el rol que desempeñan los Círculos de Mejoramiento Continuo (CMC´s) como un vehículo efectivo para alcanzar los objetivos de la empresa. Los CMC´s están integrados por trabajadores de un mismo proceso, a quienes se capacita en el manejo de herramientas, técnicas y metodologías de la calidad, con la finalidad de realizar mejoras en los procesos. En ese sentido, en la compañía minera La Poderosa, la administración es participativa y el directorio difunde las políticas, para lograr la rentabilidad de la empresa. Así también, los mandos medios definen los objetivos y estrategias, desplegándola en cascada a la supervisión y estos a su vez, al personal de línea. Este concatenamiento de responsabilidades y la participación de los CMC´s aseguran el alineamiento y control de la gestión.

Sep 12, 2005

By W. H. McAllister

The paper considers the geology and the coalfields that comprise the Scottish south area. It traces the history of known sources of spontaneous combustion and indicates the collieries concerned, with the position of the seams in the geological series where heatings have occurred. The methods of work over the years are described. It relates in detail the circumstances surrounding a fire at Bilston Glen Colliery in the Lothian Coalfield, and the heating at Killoch Colliery in the Ayrshire Coalfield, and the steps taken to deal with them. It also describes some of the difficulties in steep seam working. Methods adopted to prevent spontaneous combustion throughout the area are discussed, and some detail of the UNOR gas analyser is given. Finally, it comments on the present techniques in use in the area, particularly at Bilston Glen Colliery, to prevent spontaneous combustion.

May 23, 1905

By Laurens de Jonge, Wiebe Boomsma, Rodney Norman, Stanislav Verichev

"Earth provides natural resources, such as fossil fuels and minerals that are vital for human life. As the global demand grows, especially for strategic minerals, commodity prices rapidly rise. Thus there is an identifiable risk of increasing supply shortage for minerals. Hence a major element in a long-term economic strategy must be, to ensure security of supply for these strategic minerals. In this rapidly changing global economic landscape, deep sea mining has gone from a distant possibility to a likely reality within just a decade.Although deep sea minerals extraction was investigated in the 1970’s, it was abandoned because of changing commodity economics, advances in on-land exploration techniques, growing concern on environmental impact, and political and legal aspects with regard to ownership issues. The developmental data from those days, if still available, are not adequate to allow engineering and building of an integral system for extraction of deep sea minerals without additional R&D work. Thus, deep sea mining is yet to attain a Technology Readiness Level (TRL) sufficient to successfully undertake deep sea mining operations, from resource discovery to resource assessment and to resource exploitation [Blue Mining, 2014]."

Sep 1, 2014

By Klaus Rieker

North of Antwerp central train station, two single-track tunnels for the high-speed train line between Brussels and Amsterdam were constructed. At the same time, the central train station was modified to a through station. Both 1.23 km tunnels are situated in the Antwerp sands and were constructed using a slurry shield machine. Due to the inner city location, the tunnels run over their entire length underneath structures, in some cases with only minimal clearance. The paper deals with these challenging situations. In addition, the tunnel boring machine, the tunnel lining and measures to limit settlements will be introduced.

Jan 1, 2007

By L. C. Graton, Joseph Murdoch

I. Introduction......................... 26 1. The Relations of Scale in Geologic Work........ 26 2. General Characteristics of Copper Sulphide Ores..... 29 3. Scope of Present Study................. 31 11. Description of the Important Minerals............ 36 1. Pyrite....................... 36 2. Pyrrhotite....................... 41 3. Chalcopyrite...................... 41 4. Bornite........................ 40 5. Covellite....................... 50 6. Chalcocite....................... 52 7. Enargite...................... 59 8. Tetrahedrite and Tennantite.............. 61 III. Conclusions.......................... 62 I. Introduction. The Relations of Scale in Geologic Work. Many features of human accomplishment rest upon the possibility of representing natural objects on a scale of different magnitude from the actual one. Most drawings, for example, are of very different scale from that of the object depicted, and indeed are useful mainly 011 this account. More important than the question of mere convenience, however, is that of meeting the physical limitations of vision.' Thus, a mural

Jan 1, 1914

Safety rules for installing and using electrical equipment in and about coal mines covered in this information circular supersede those previously included in Bureau of Mines Bulletin 514, issued in 1952. This revision brings these rules up to date and more nearly in line with present operating and safety practices in the industry. The rules are intended to supplement existing Federal and State regulations, and no provision shall be construed to oppose or supersede any provisions of the Federal Mine Safety Codes, the Federal Coal Mine Safety Act, or the mining laws of any State. The rules were designed to permit progress, such as application of new or improved materials and equipment or use of new practices where these materials, equipment, or practices retain or improve the level of safety established by these requirements. It is hoped that they will fill the need for a concise edition for mine electricians and electrical engineers, especially those who do not have ready access to more detailed rules or codes.

Jan 1, 1964

By G. L. Liu

"Deformation Banding ( DB ) in cold rolled mild steel has been experimentally established by microstructure investigation. Deformation banding model includes such deformation mode when it is applied to rolling texture simulation. The cause for the occurrence of deformation banding is the reduction of the total work for plastic deformation through a relaxation of the deformation constraints. In the first DB model, all grains are assumed to band from the first deformation step. Such an unrealistic assumption has been eliminated in the new model by the introduction of a banding criterion based on an energy minimizing approach. The prediction is closer to the measured texture by applying banding criterion and setting critical resolved shear stresses (CRSS) ratio for { 110 } and { 112 } slip modes to 0.85.IntroductionBased on the continuum theory of plastic flow and deformation mechanism of crystallographic dislocation slip, Taylor's FC ( Full Constrain ) theory [1] has been widely used in texture modeling. As the process of cold rolling of sheet materials produces a microstructure consisting of elongated or equiaxed flat grain or cell, the ""lath"" and ""pancake"" relaxed constraints ( RC ) models [2, 3] were introduced as the successful improvements over the classical FC model. It has been also recognized that crystals may split into different orientations during deformation and the term deformation banding is used to describe such deformation processes [4, 5]. Lee et al. [6, 7] pointed out that the success of the RC theory in predicting textures depends on the physical processes of deformation banding. They developed so called Deformation Banding ( DB ) model by considering DB in the longitudinal plane to be accounted for by the RC method and allowing DB in the rolling plane. DB model was applied to simulate the texture development in bee case [8], the predicted bee rolling textures are in reasonable agreement with the measured textures. In the first DB model, however, all grains are assumed to band right upon the first deformation step. A banding criterion was formulated [7] which states that DB will occur if the work used in DB model is less than that in RC model. Such criterion has been incorporated into the original DB model for texture simulation and is referred to as DBC ( Deformation Banding Criterion ) model."

Jan 1, 1998

Safety rules for installing and using electrical equipment in and about coal mines covered in this information circular supersede those previously included in Bureau of Mines Bulletin 514, issued in 1952. This revision brings these rules up to data and more nearly in line with present operating and safety practices in the industry. The, rules are intended to supplement existing existing Federal and State regulations, and no provision shall be construed to oppose or supersede any provisions of the Federal Mine Safety Codes, the Federal Coal Mine Safety Act, or the mining laws of any State. The rules were designed to permit progress, such as application of new or improved materials and equipment or use of new practices where these materials, equipment or practices retain or improve the level of safety established by these requirements. It is hoped that they will fill the need for a concise edition for mine electricians and electrical engineers, especially those who do not have ready access to more detailed rules or codes.

Jan 1, 1964

By Huang Zhiwei, Paul Skayman, Kevin Holley

In 1989 The First Brigade for Geology and Mineral Exploration of Qinghai Province discovered gold at Jinlonggou and Qinlongtan, Tanjianshan. Between 1992 and 2002 small scale mining was carried out at these sites using underground mining methods at Jinlonggou and an open pit at Qinlongtan. During 2003 and 2004 geotechnical investigations were carried out in support of a bankable feasibility study. An important objective of this investigation was to meet both internationally accepted standards and codes of practice, and also to satisfy the Chinese requirements. Extensive use of local experience was utilised. Where possible geological drilling information was incorporated into the assessment. Extensive geotechnical mapping of surface and underground exposures, and index testing to gain an appreciation of rock intact strength were used to characterise the sites. Rock mass classification (MRMR) was used to assess indicative overall slope angles and appropriate bench stack heights for the proposed pits at Jinlonggou and Qinlongtan. Measured discontinuity orientations were used in kinematic analysis to assess stability of possible pit slope geometry at a batter and overall scale to provide preliminary recommendations for the pit slope configuration. Numerical modelling was also carried out to improve the understanding of anticipated pit behaviour. Site investigation and preliminary geotechnical design details, that incorporate site specific conditions for the formation of open pits at Tanjianshan, are discussed in this paper.

Jan 1, 2006

By W. R. Reed, J. P. Rider

"The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) recently developed a series of models using computational fluid dynamics (CFD) to study airflows and respirable dust distribution associated with a mediumsized surface blasthole drill shroud with a dry dust collector system. Previously run experiments conducted in NIOSH’s full-scale drill shroud laboratory were used to validate the models. The setup values in the CFD models were calculated from experimental data obtained from the drill shroud laboratory and measurements of test material particle size. Subsequent simulation results were compared with the experimental data for several test scenarios, including 0.14 m3/s (300 cfm) and 0.24 m3/s (500 cfm) bailing airflow with 2:1, 3:1 and 4:1 dust collector-tobailing airflow ratios. For the 2:1 and 3:1 ratios, the calculated dust concentrations from the CFD models were within the 95 percent confidence intervals of the experimental data. This paper describes the methodology used to develop the CFD models, to calculate the model input and to validate the models based on the experimental data. Problem regions were identified and revealed by the study. The simulation results could be used for future development of dust control methods for a surface mine blasthole drill shroud. IntroductionIn surface mines, production drilling is an essential process in blasting to fracture the hard rock overburden for removal. During the process, considerable amounts of respirable dust are produced. Past sampling at the shroud area of blasthole drills had documented time-weighted-average respirable dust concentrations ranging from 8.68 to 95.15 mg/m3 (Organiscak and Page, 1995) and 1.04 to 52.30 mg/m3 (Listak and Reed, 2007). These high dust concentrations, which may contain silica, can lead to respirable dust overexposures for the miners working nearby. These overexposures can lead to silicosis, an occupational lung disease that has no cure and is ultimately fatal.Two basic methods are used to control drilling dust: a wet suppression system or a dry collection system (Cecala et al., 2012). Dry drilling techniques using a dust collection system are preferred in rural mining locations where a constant water supply is not available, and in the case of rotary drilling where water is associated with accelerated bit wear due to bearing degradation and hydrogen embrittlement. In addition, dry drilling eliminates freezing-related issues with water in colder climates. Dry dust collectors are highly effective at removing dust, especially the finer material, as long as they are properly operated and maintained (Listak and Reed, 2007; Organiscak and Page, 2005)."

Nov 1, 2016

Although these subterranean cavities are common to the Broken Hill big lode, yet the Broken Hill Proprietary is the most prolific in their occurrence, loud they have been found of various dimensions almost from the surface down to the lowest levels yet attained in that mine. Many of these vugbs have contined valuable silver, copper and lead deposits, and some have been remarkable for the beautiful forms of crystallization pendant from the roofs and walls, and collected on the floors. The question arises, How are these caverns and fissures in the ore body formed? There are numerous theories more or less feasible, but that the causes are variant is demonstrated beyond doubt. That water in its passage leaving channels, is one ofthe chief factors for their production is assured, and their presence is likewise due to the shrinkage and dropping of the earth from varions causes, to the deposition of material forming ledges overhanging, and thus leaving spaces below, and also to chemical erosion and electrical action both of which latter are constantly at work in reconstructing, segregating and dissolving tlie mineral and metallic constituents of all ore bodies.One of the most remarkable vughs yet discovered in the big mine was that opened up about three months bitek in the' heart of the ironstone body on Block 11, and located about 40 feet below the 100 feet level of Weatherley's stopes, but now destroyed in the progress of work. Probably it was caused by chemical action, the eating out, so to speak, of a soft and soluble portion of the manganic iron, leaving a,hollow about 15 feet long, with a width and height, of say, 6 feet, carpeted with beautiful zinc with a modicum of limeincrustations, apparently produced by the percolation from around the carbonate waters holding these minerals in solution. This cavern was divided into, what might be termed, a double chamber, by big boulders of manganic iron, also coated with an aggregation of small crystals of zinc and lime although the actual proportion of the latter was not determined.

Background geochemistry of streams in mineralised terranes is affected by (a) natural sulphide oxidation and associated metallic discharges; and (b) previous mining history and associated discharges. Both of these processes elevate background metal concentrations by (i) directly adding dissolved metals to stream water; and (ii) adding sulphide-bearing sediments' to the stream system, to be trapped in old channels and bars for later chemical decomposition in situ or after flood reworking. Definition of downstream geochemical background, involving sediments and low-flow dissolved chemistry prior to mining is prudent, as this will provide a benchmark for any required estimation of new inputs from, for example, accidental tailings discharges. Two high-profile examples from western USA illustrate these points. Summitville mine in southern Colorado is an environmental disaster left when the operating company went bankrupt in 1991. Acid metal-rich discharges are leaving the site into a river system used for agricultural irrigation. However, nearby sub-catchments have substantial naturally occurring acid metal-rich discharges and locally discharge natural sulphide-rich debris flows into the same river. Distinction between natural and anthropogenic pollution in the downstream reaches is difficult. Early mining at Cooke City, Montana (New World District) released large volumes of sulphide-bearing tailings into the river system when a tailings impoundment dam failed. The event was equivalent to a 100-year flood, and tailings were deposited for 30 km downstream. These tailings are currently oxidising, and are being reworked into the modem stream during high flow events, thus perturbing background geochemistry.

Jan 1, 1999

By A. T. Robles, L. Buckingham

"When certain gold ores containing pyrite, graphite, humates and fumates or other organic compounds which are possibly adsorbed on clay minerals are treated with aqueous solution of alkali metal cyanide, the aurocyanide complex which forms is adsorbed by these ""pregrobbing"" species in the ore. Dissolution of gold proceeds until chemical equilibrium is attained between the cyanide complex adsorbed by the ore and in solution.Sodium lauryl sulfate (SLS) may be used to decrease the adsorptive activity of the prerobbing species in the ore. It has successfully improved recovery at Holt-McDermott Mine and is highly biodegradable.INTRODUCTION Precious metal-bearing ores containing preg-robbing species are poorly amenable to standard cyanidation techniques. The ""preg-robbing"" impurities with which they are associated tend to adsorb the gold cyanide complexes and carry them through the circuit to the tailings. Also, gold may be associated with these impurities in the ore and not be leached by the cyanide complexing agents used in conventional cyanidation techniques.Methods for dealing with the problem of preg-robbinq impurities in gold ores are:Carbon-in-Leach (CIL), in which granular activated carbon is added to compete with preg-robbing species for the gold cyanide complexes. This process can improve gold recovery in mildly preg-robbing ores especially when fine carbons with very high activities are used. However, with severely graphitic ore, the carbon associated with the rock may outperform the granular activated charcoal.Chemical Oxidation, in which the ore is subjected to preliminary chemical oxidation techniques to oxidize carbonaceous materials using such diverse reagents including ozone, sodium hypochlorite, calcium hypochlorite, chlorine gas, permanganates, perchlorates, chlorates and oxygen prior to subjecting the oxidized ore to standard cyanidation treatment to extract gold. This is generally a costly method and will not prove economical on a low-grade ore."

Jan 1, 1992

By Eddine Chafika

El presente texto señala las diversas etapas de la exploración de Bear Creek Mining Corporation y su influencia en crear las condiciones para que las comunidades apoyen una mina, donde el resultado previsto de las relaciones comunitarias en las etapas de la exploración y minería, es el impacto sostenible y constructivo cuando el trabajo termine, no importa cuánto tiempo dure esto.

Sep 9, 2007