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By W C. Burton, J S. Kuszma, T O. Aspinall

The environmental impact of mining and evolving environmentallegislation has received increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental regulatory agencies and members of the public. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. There is thus the need to increase the base of knowledge on the existing practices of spoil dump design and rehabilitation. Efficient engineering design and systematic economic evaluation of spoil dump reshaping techniques for mine rehabilitation assists in maintaining the expected standards of environmental compliance. As part of the overall approach for effective engineering design ofspoil dumps, a comprehensive, computational and efficient tool isrequired for assessing the economics and productivity of existing spoil dump reshaping practices for efficient mine rehabilitation. Such a design tool is useful in linking current spoil dump environmental management practices with engineering design planning and economic impact evaluation. This paper identifies the processes for the economic impact evaluation for existing spoil dump reshaping practices and proposed final site dump designs. Selection of an efficient spoil dump design at optimum costs will ensure operational efficiency. A case study is presented identifying economic impact evaluation in earthmoving equipment selection and the costs involved for the reshaping of spoil dumps to that of varying final site designs.

Jan 1, 2000

By H. Yavuz

Closed form solutions assume opening shape to be circular to simplify the calculation of the ground response curve for the design of underground openings. However, in mining and civil engineering works, non-circular openings are commonly excavated. Therefore, there is a need to estimate the ground response curve for such openings. In this respect, a simple model for circular, arch and rectangular shape underground openings subject to a hydrostatic stress field is the aim of this study. A comprehensive numerical modelling, using the finite difference method, based on numerical modelling code FLAC version 4.0, was carried out. In addition to shape of an opening, the effect of rock mass strength, opening size, in situ stress on strain (tunnel deformation to tunnel radius) of the opening in response to applied support pressures was investigated parametrically by developing models for each specific condition. The strain results for each excavation shape obtained from this large number of models against the normalized strength of rock mass and internal support pressure with in situ stress magnitude were evaluated by multiple regression analysis. As a result, a model that was well correlated to data was developed for an overall estimate of the ground response curve depending on relevant effecting parameters. The regression coefficients of the model were given for estimating both roof and sidewall response curve of each excavation shape. The model was verified by statistical tests and by an analytical solution. Diagrams were also established to highlight the influence of relevant parameters and to estimate the support pressure for a stable opening staying within the acceptable limits of strain. Strains occurring in a rectangular opening are found to be larger than those in the arch and circular openings for the other fixed parameters. In the mean time, larger strains occur around an arch shape opening than a circular opening.

Jan 1, 2006

By F. Calizaya

The Western Mining Training and Translation Center is a consortium of four universities devoted to developing educational and training projects to reduce the incidence/accident rates in the mining industry. The center consists of Missouri University of Science and Technology, Montana Tech, the Colorado School of Mines and the University of Utah. It is fully funded by the National Institute for Occupational Safety and Health (NIOSH). The center manages 15 educational projects and one translation project. Hazard Identification and Risk Assessment (HIRA) for Small Mines is an educational project managed by the University of Utah. The objectives of this project are to identify critical mine hazards, assess risks; outline procedures to reduce accident/incident rates in small mines in the western United States and to train mine workers and super-visors on HIRA in each participating mine. To accomplish these objectives, the HIRA personnel visited 15 small mines in Utah, Colorado, Nevada and California. At these mines, most operators were employing independent contractors to perform several tasks ranging from drilling, blasting and mucking of rock at the work site to hauling ore to a processing plant. The operation of diesel-powered equipment was one of the major tasks performed by the contractors. This article presents three case studies in which contract workers performed a number of tasks with no reportable incidents but did so unsafely. It also highlights the training received by most contractors, the constraints imposed upon them and the safety hazards to which they are exposed most frequently.

Jan 1, 2008

By W. R. K. Wu

This Bureau of Mines report presents a statistical study of the repeat abilities of coal-plasticity parameters obtained in the tests with the Gieseler plastometer and the Audibert-Arnu and Hoffmann dilatometers. Repeatability is expressed in terms of one or two standard deviations for the differences between duplicates. The statistical method employed here is summarized. Results are tabulated for the temperature and nontemperature parameters of the three tests.

Jan 1, 1970

By Loren R. Anderson

This Volume documents the use of the Cone Penetrometer data analysis computer programs VERT and HORZ. The programs are interactive in that they prompt the user for input data and allow correction and modification to be made. The programs read data from the results of cone penetrometer soundings and convert the data to values of tan ø. Mean, standard deviation, skew, kurtosis, linear trends and autocorralation are computed by the programs.

Jan 1, 1982

By Kostas Kaklis, Zach Agioutantis, Robin Flattery

Pillars are used as the primary support structures for underground mining to maintain stability by supporting the over laying strata. In the case of horizontal seams, the pillars are typically subjected to axial loading due to the weight of the overburden and/or abutment stresses, while in the case of inclined seams they are subjected to oblique loading due to both the vertical and horizontal in-situ stress.

By L. S. Rivett, U. M. Oko

The Strathcona mine, with a large new underground operation and concentrator, was recently brought into\ production by Falconbridge Nickel Mines Ltd. The tailings disposal and water utilization problems at Strathcona are described in this paper, with sections devoted to the Moose Lake watershed system, tailing impounds, the construction of dams and the operation of the Moose Lake neutralization plant for the elimination of acidity, including the equipment used.

Jan 1, 1971

By Douglas W. Barr

If some of you have been through the long hot summer in the southwest, you may find it refreshing to turn your thoughts to the wintertime problems of mineral processing in the northern climates. The purpose of this paper is to point out some of the ways in which heat is gained or lost in the tailing basin operation and the problems that can result if too much heat is lost.

Jan 1, 1980

By John Nagy, Austin R. Cooper

Information is presented on the pressure and rate of pressure development during a dust explosion . The data were obtained in laboratory studies in a 75- cubic inch vessel with mineral , agricultural and chemical dusts . The factors investigated include dust concentration , oxygen concentration of the atmosphere , admixed inert powder , and admixed moisture . Information is given also on the effects of these factors on the composition of the atmosphere after the explosion .

Jan 1, 1964

By Moisés Paulo Teixeira

The use of tailings for the synthesis of new materials is a worldwide concern today. This paper approaches the utilization of tailings of soapstone (steatite) in order to produce ceramics. The results show that the addition of soapstone in a ratio over 20% in the ceramic mass has enhanced the bending resistance of the ceramic samples when they were fired at temperatures of 900°C or 1000°C.

Oct 30, 2017

By AIME AIME

THE PAPER, "Surface Effects on Assay Beads Caused by Metals of the. Platinum Group," presented by J. L. Byers, before the Institute of. Metals Division at the February meeting of the Institute, is the subject of interesting discussion, an abstract of which follows. The original paper is available at Institute headquarters as a Preprint. Member-What assurance have you that the percentage of metals, as stated, is really an accumulation?

Jan 1, 1932

By U. B. Kodukula

Attempts are made to evaluate the feasibility of using a water-injection cyclone for the concentration of iron ore fines. The separation characteristics of clay fines, containing large amounts of alumina and silica, from the iron values are discussed. The effects of critical variables, such as injection water rate, truncated cone diameter, spigot opening and vortex finder diameter, on the performance of a water-injection cyclone in terms of iron, alumina and silica grades; iron recoveries; and alumina and silica rejections are discussed. A set of 16 full-factorial experiments (24) was carried out to gain an understanding of the individual and interaction effects of the variables. The results indicate that classifying iron ore fines containing 63.0% iron, 2.5% alumina and 3.5% silica through a water-injection cyclone can produce concentrates with iron grades greater than 66.0% and alumina and silica contents less than 1.5% and 2.0%, respectively, at different study conditions. The achievable iron recovery values are greater than 88%, and alumina and silica rejections are more than 80% and 50%, respectively, within the specific study conditions. While the truncated cone diameter, injection water rate and spigot diameter influences the alumina rejection to a considerable extent, it is mostly influenced by the vortex finder diameter. The iron recovery and silica rejection values are mostly influenced by spigot diameter and truncated cone diameter. The effect of injection water on the concentration characteristics depend on the prevalent truncated cone diameter and spigot diameter conditions.

Jan 1, 2008

By John R. Hugens

Modifications in the ALSCAN method of measuring hydrogen dissolved in liquid aluminum have made it possible to monitor the level of hydrogen dissolved in liquid copper. Measurements from the tundish show a correlation with eddy current readings from the continuously cast and rolled copper rod from the continuous casting and rolling system at Amarillo. The measurements also indicate that the copper in the tundish is supersaturated with hydrogen.

Jan 1, 1994

By M. Naymanbayev

The characteristics of the mineral composition of ores and valuable set of components: the technology of processing depending on the type of mineralization, the nature of the impregnation of ore minerals and their composition have been considered. There have been given technological schemes for processing concrete objects. The analysis of fitness fields for industrial development (degree of scrutiny, the effectiveness of developed enrichment and hydrometallurgy technology) has been provided.

Sep 1, 2012

By P. Gaskell

The paper examines the development of rock movement between a longwall extraction horizon and the surface for a fully caved mining situation. Physical modelling has been used to examine the mechanics of ground movement and the propagation of fractures around the longwall working. The paper discusses dimensional analysis, model construction and measurement technique and data processing of the results into effective graphical forms for further study.

Jan 1, 1988

By E. Ettles

This paper features some of the spectacular new advances in the fields of fluorescent penetrant inspection and magnetic particle concentration. Casting fractures in the various stages -before the repair, during the repair and in the completed repair -using the cold process method will be discussed. This cold method of repair eliminates problems of pre-heating and cooling and the stress factors that are involved in any heat repair.

Jan 1, 1971

By A. W. Ambrose

The output or oil and gas rrom the producing fields in the United States is rapidly deelining. Coincident with this decline is a steadily increasing demand ror petroleum and its products, but at present there are no commercial substitutes ror gasoline and lubricating oil. Undoubtedly, many new fields will be discovered in this country during the next rew years. Indeed, there may be periods or temporary flush production that ror a rew months or a year or perhaps two years will afford a surplus. Such peaks are temporary and should not be given too much weight in considering the relation between petroleum supply and our national lire. In considering this problem we must regard a long period or time, and, ir we do that we shall see that domestic production will be unable to keep pace with consumption. Hence, the public good demands t~at the highest efficiency obtainable be practiced in the production or oil. To accomplish this end, the operator or to-day should so organize his rorces ror development and production that he recovers every barrel or oil that can be recovered at a profit. This necessarily involves the use or eeonomical and scientific methods or development a:nd production and the elimination or waste. The Bureau or Mines has ror years urged the conservation or petroleum and its products, and has pointed out that -such conservation should start before the oil is brought to the surface rather than arter it is in storage tanks. Losses or petroleum underground have undoubtedly been rar greater than losses in storage, in transportation, and in refining. The quantity lost usually is indeterminate, and hence difficult to express in terms or money, but by remembering that entire oil fields have been ruined by invadIng waters some idea may be gained or the importance or underground waste. The petroleum engineer is coming to be recognized as an extremely important aid in the intelligent development or oil fields. In this paper an effort is made to outline ror the engineer and producer a field or work whereby science and engineering not only can but have been applied practically. The mining engineer has been the direct- ing hand in the development of mines, and it is being recognized more and more that the petroleum engineer has a similar function in developing oil properties. Thispaper aims to show the general method of procedure in studying underground conditions in producing oil fields and how such study may not only correct but even prevent great unnecessary losses. Such work provides the company with maximum insurance for the field against loss and is accompliphed at minimum cost and minimum risk. Throughout the paper reference is made to oil wells and oil fields, but to a certain degree many of the suggestions relating to oil wells are applicable in the care and protection of gas wells and in solving gas problems.

Jan 1, 1921

By R. Gutray, J. E. Grainger

This paper deals with the use of a cement-deslimed mill tailings mixture for a scraping floor in cut-and-fill stopes at Madsen Red Lake Gold Mines Limited. It describes the mixing and placing procedures and the precautions used with respect to the floor while mining in the stopes. Details of the mix are presented, and advantages and disadvantages discussed. The paper concludes with a brief outline of the costs.

Jan 1, 1966

By C. Musingwini

The Bushveld Complex is economically significant and strategically important to South Africa, thus it is imperative that optimal extraction of platinum group metal (PGM) resources on the Bushveld Complex is achieved. Optimal extraction broadly requires that the maximum amount of ore is extracted by excavating and hauling the minimum amount of waste in the shortest possible time, at the least cost, and in the safest and most environmentally acceptable manner. In open-pit mine planning this entails among other things, minimizing the waste stripping ratio, whereas in underground mine planning it includes minimizing the metres of waste development. In conventional mining, the main development that is in waste or partly in waste and defines the mining grid pattern includes levels and raises. It was prudent to consider optimizing level and raise spacing in conventional mining because the method is a prevalent mining method on the Bushveld Complex accounting for nearly 70% of platinum production.

Jan 1, 2010

By Angela Binder, Mareike Schubert, Yichen Jiang, Sandra Nowosad, Oliver Langefeld

GermanyINTRODUCTIONThe mining industry is currently characterized by various factors such as environmental impact, resource scarcity, social responsibility and geopolitical uncertainty. The production of minerals required to meet the demand for renewable energy is expected to increase by 500 % by 2050, particularly for critical minerals such as graphite, lithium and cobalt 1. Easily accessible deposits are often depleted, meaning that deeper and more complex deposits need to be developed. Furthermore, investors’ value systems have shifted towards more sustainable practices. Alternative approaches to solving this problem are therefore currently being developed, such as the Modular Mining Systems concept for scalable and adaptable mining projects 2. Many mining companies have also taken important steps to become more sustainable, implementing measures such as proactive closure strategies, restoration programs and the development of renewable energy projects. In the European Union, laws such as the Critical Raw Materials Act and the Net Zero Industry Act support the mining industry 3,4. They see it as important for the energy transition and promote more sustainable ways of working in the industry Particularly negative environmental impacts such as land degradation, scarcity of local water resources, water pollution and greenhouse gas emissions are ingrained in society’s memory. Despite these efforts, the public image has not yet changed. To change this perception, the industry must strive to better communicate its sustainable practices and the steps it is taking towards a more responsible and sustainable future, promote transparency and build trust.Digitalization, automation and electrification are driving the digital transformation in mining. However, their implementation can lead to higher capital expenditure, limiting their adoption across the industry. Furthermore, implementing new technologies can be a daunting task for any organization. Change management comes into play when introducing such disruptive technologies. It involves preparing an organization for change, potential resistance and establishing effective communication. This helps to ensure that the implementation is successful and the benefits of the new technology are maximized. Digital transformation requires well-trained, young mining, electrical, mechatronic and software engineers with a deep understanding of information systems. Unfortunately, the industry faces the enormous challenge of attracting this younger generation, who have little interest in the extraction of raw materials. The need for action is compounded by an aging active workforce heading into retirement and the forecast of increasing demand for critical minerals.In this challenging environment, the concept of Blue Mining with its constant further developments represents a promising approach. This implies a shift from a linear to a sustainably oriented circular economy. For the mining industry, this specifically means the introduction of innovative technologies, the increased recovery of materials from waste and the consistent questioning and application of circular principles along the entire life cycle of a mine. Such a change can not only reduce the environmental impact, but also contribute to economic resilience and increased social acceptance of mining.

Feb 1, 2025