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By George J. Saulnier

The U.S. Geological Survey has developed mathematical-modeling techniques to assess potential impacts on the hydrologic system resulting from mining of coal and oil shale in northwestern Colorado. Potential impacts of oil-shale mining on ground-water hydrology have been simulated using a quasi-three- dimensional finite-difference model. The model has been used to simulate hypothetical mine-dewatering operations at two proposed oil-shale mines. Dissolved-solids distribution and solute transport were simulated with a three- dimensional finite-difference model that was used to evaluate the effects of flooding in hypothetical abandoned mines. The potential impacts of coal and oil-shale mining on watersheds were investigated using a digital watershed model. This deterministic physical- process model predicts responses of the hydrologic system to modifications resulting from mining in basins having snow as the major source of runoff and recharge. Potential impacts of coal development on surface-water quality were investigated using a river-quality assessment model.

Jan 1, 1979

By D. J. Lucifora

Monitoring-While-Drilling (MWD) is a proven technique that records instantaneous on-drill parameters which can be used to supply contextual information for in-situ, down hole conditions, such as: changes in geology, the presence of pre-existing fractures and dynamic alterations, down hole conditions including bit bailing, bit blockages and bit wear, and improper drill operation. This technique has been widely used in the oil and gas industry and, eventually, it was transferred to the mining industry. A challenge when analyzing and interpreting MWD data is in utilizing proper filtering which enables one to properly eliminate any ?noise? from the signals of interest. Overall the importance of MWD data is that, through the collection of operational field-based data, a dataset can be acquired which allows experimentation and analysis to be carried out. Such a dataset is often impossible to replicate in a laboratory setting. If successful, and through iterative refinement, any promising method can eventually be implemented on-machine and using real-time monitoring techniques. This paper will provide a state of the art review of presently used MWD techniques and applications in industry. The paper?s primary focus will be on shallow, mining-style, blast hole drilling but will also take into account techniques and applications utilized in oil and gas drilling which have not been adopted in the mining industry. In the cases where MWD techniques and applications exist solely in oil and gas drilling the paper will examine and comment on the potential utility of technology transfer to mining applications.

Aug 1, 2013

By Stephen B. Cheeseman

The quantity of data available and the rate at which we access such data are rapidly increasing. Electronic data capture systems, fleet management systems and a host of other technological advancements have created a constant stream of real-time, tactical data. However, are we taking advantage of this data? Are we converting data into useful information to aid in efficient decision-making? Mining operations are struggling with ?information overload?, finding it difficult to extract the benefits from vast stores of data. Without the necessary tools to facilitate a data filtering and information reporting process, most operations revert to old practises such as re-entering data into multiple spreadsheet reports. As a result, the ability to make effective use of data still eludes many mining operations. Some operations have taken audacious steps to rectify this situation. The De Beers Venetia mine in South Africa has implemented an integrated mining information technology solution that transforms their data into practical, usable information allowing staff and management to make decisions that improve efficiencies and reduce costs. In the absence of quantitative justification or ROI, De Beers took a risk in implementing change. Today, they are realising the benefits. This paper will unearth the information technology issues that surfaced during the Venetia implementation, then identify the benefits De Beers has obtained from deploying an integrated mining information technology solution at the Venetia mine.

May 1, 2002

By Rollin A. Slater

The bulk materials handling industry has served silently for years as the skeleton structure and often the central system of nerves and nourishment for the body of basic production industries. During the past two decades, this body has undergone substantial growth and mutation to meet the surging demands of our national economy for more and better products. The steel industry has been prominent in this phenomena and plants of the sixties are as unlike the second war vintage as our current crop of basketball players differ from their fathers. Steel has kept pace with spiralling demand by innovation which has resulted in new processes and improved designs which generally yield greater production from fewer units. The supporting industry of materials handling has likewise improved its techniques and currently has a new stronger generation of equipment to perform its necessary supporting function. It has been my fortunate experience to have been instrumental in the creative stages of several new steel mills which are currently in conceptual design or actual construction. Drawing upon exerpts from this experience, this paper will describe a basic approach to the selection and application of modern bulk materials handling systems to an entirely new steel plant. Specific details of past work are not available for publication, therefore, the plant described herein is a composite of ideas and will be the new plant of the Hypothetical Steel Corporation which will be located on the lower shores of the Great Lakes.

Jan 1, 1967

By J. P. Norrie

The presence of copper-bearing rocks in the Coppermine River area of Arctic Canada has long been known. Word of this was probably circulated along the Arctic and Hudson Bay coasts by the Eskimo, who no doubt traded articles made from native copper among themselves. It is not known whether any of these ever reached the southern shores of Hudson bay. The Indians, also, knew of the occurrence of copper here, as they served as guides to Hearne when he made a successful trip over land from Hudson bay to the Coppermine river. The possible commercial importance of these copper deposits was early appreciated by the Hudson's Bay Company, who on December 7th, 1770, despatched Samuel Hearne from Fort Prince of Wales, now Fort Churchill, to investigate them. He reached the then unnamed river at a point forty miles from its mouth on July 14th, 1771, and after surveying the river to its mouth and naming it the Coppermine, he retraced his steps to Fort Churchill by an overland route. Hearne's expedition was probably the most remarkable and arduous ever attempted in Arctic exploration, but the actual value derived from the trip was entirely out of proportion with the hardships he must have suffered. He verified the occurrence of native copper, but his astronomical and other observations were of little value. Until 1912 no concerted effort was made to obtain any definite information as to the geology and economic value of the Copper-mine deposits.

Jan 1, 1931

By Nicole de Jager, Michael J. Nicol

"In order to liberate gold from refractory gold ores and concentrates it is generally necessary to oxidise the surrounding sulphide minerals, typically pyrite and arsenopyrite. Traditional methods of oxidation include pressure leaching, roasting and bacterial oxidation. In recent years, bacterial and pressure oxidation have found increasing favour, although these methods are by no means completely satisfactory and each is subject to particular disadvantages.A novel process has been developed as an alternative to the traditional methods whereby electro-generated ferrate(VI) ions in alkaline solution are used to oxidise a pyrite concentrate. This process has been observed to proceed fairly rapidly and could prove to be a more economically viable process, as well as being more environmentally acceptable. As an added benefit, operating in an alkaline environment is advantageous for downstream cyanidation processes.Ferrate(VI) is a relatively unknown species, due mainly to its instability in acidic solutions. However, in alkaline solution it has been observed to be sufficiently stable for use as an oxidant when used under favourable conditions. Ferrate(VI) is most conveniently manufactured electrolytically via the dissolution of high-carbon anodes in strongly alkaline solutions. Some literature has been published on the electrolytic generation of ferrate(VI) and relatively high efficiencies have been observed by both the authors and other researchers.This study utilises both electrochemical techniques and leaching experiments to examine the kinetics of the oxidation of pyrite by ferrate(VI), which is produced electrolytically. Cyclic voltammetry, rotating disk voltammetry and potential step experiments have been used to investigate the kinetics and mechanism of the oxidation process."

Jan 1, 1997

By J Ortiz

In almost all copper mining companies, mine planning is done considering different time frames, leading to long-term (life-of-mine) (LOM), medium-term (first three years) and short-term (first year, monthly, weekly, and up to daily plans). Shorter term plans are usually associated with more abundant information, hence models with lower uncertainty. However, they capture more of the variability found on the geological attributes. In long-term models, usually estimation methods tend to hide this variability, providing smoothed interpretations.Medium and long-term plans consider average values for the parameters and optimisation techniques are applied aimed at maximising the economic profit. Short-term plans, on the other hand, are made to comply with the medium-term promises, maximising the use of the available resources (equipment and processing capacities) and dealing with the variability not characterised in the previous planning stages. This generates an important gap between the short-term and the medium and long-term plans. A case study was made using an important oxide copper mine, where the variability found in the short-term plan has a large impact in the productive process, thus reducing the daily ore grade variability is an important goal. In this paper, this planning issue is addressed by creating medium-term mine plans using mixed integer programming which are compared using the output of a simulation of the daily extraction that is aimed at satisfying the daily constraints of the processing plant, the availability of mining equipment and the variability of ore grade. The result shows the expected gap between these mine planning processes, which suggests correcting some of the parameters used in future medium and long-term plans.

Sep 26, 2011

By Reinhard Gertl, Maximilian Weithaler, Harald Kammerer, Juan Pablo Muñoz, Juan-Carlos Rueda

The Guillermo Gaviria Echeverri tunnel and its access roads project in Antioquia, Colombia is a mega infrastructure project that includes a road network with the longest tunnel in Latin America and several short tunnels, the latter being the focus of this study. The design of the project required careful consideration of several special factors, such as the tunnels’ steep slopes of up to 5%, high fire load of 100 MW, bidirectional operation, and short lengths that make it difficult to place ventilation equipment. The combination of all these parameters cause a challenging design problem for the ventilation systems and smoke control of the short tunnels. To address this challenge, a risk assessment study was conducted to support the design of a new and innovative ventilation strategy that deviates from relevant guidelines and standards, like the Austrian RVS [1][5][6] or the German EABT [8] in order to provide a customized solution for this particular project. This strategy resulted a cost-effective solution, that allowed a reduction in the number of required jet fans and at the same time reaches or reduces the risk level compared to traditional ventilation strategies.

Jun 13, 2023

By Betty L. Gibbs

A company must have an organized approach to effectively sort through the profusion of available software and hardware and find the programs and equipment which fit defined needs. The selection process must build a complete compatible system which includes hardware and software. The methodology presented in this paper helps identify some of the more important considerations. The steps needed for an organized approach to software/hardware selection are: •All involved staff should contribute to an assessment of current computer capabilities and projection of future needs. •Alternatives are analyzed to determine what software and hardware is available and how selections may possibly be merged into the existing computer system. The evaluation process focuses on details of program capability and hardware compatibility. Analysis must be done to determine how closely individual programs fit the established requirements. The final decision is often a balance of needs between program capabilities and hardware availability. Any programs selected must be able to run on existing and newly purchased hardware. Any additional hardware selected must be capable of meshing with the available computer system.

Jan 1, 1983

By Isabel F. Barton, Matthew J. Gabriel, CARSON ROBERTS, JOHN LYONS-BARAL, LEON DUPLESSIS, Mark D. Barton

Geometallurgical assessment of orebodies in the mining industry typically relies on bench-scale or lab-based characterization techniques. In this study, we investigate drone- and tripod-based field hyperspectral imaging as a potential addition to the geometallurgy toolkit in multiple applications. This pilot study tests hyperspectral imaging for largescale mineral mapping in and around the active Lisbon Valley copper mine, including natural exposures, previously producing U-V mines, highwalls, dumps, and leaching sites. Tests include different (supervised and unsupervised) mineral data classification methods, varying mineral spectral reference libraries, comparison with ground-truth geological and spectroscopic mapping and sampling, and integration with LiDAR data. The results show that hyperspectral scans can produce spatially registered maps of the distribution of different spectrally active mineral types over dumps, highwalls, leach pads, and natural outcrops. Clays, other phyllosilicates, carbonates, and sulfates showed up particularly well. The sensor was also able to distinguish dry from lixiviant-saturated areas and map different clay types on the leach pads, and shows promise for differentiating types and health of vegetation. These results suggest that hyperspectral imaging, if coupled with robust ground-truthing, can be a useful complement to existing geometallurgical techniques in the mining industry, such as geological mapping, blast hole sampling and automated mineralogy identifications, and handheld spectrometry. In particular, hyperspectral imaging has promise for mapping the distribution of acid-consuming minerals; mapping the distribution of swelling, sliming, and heap-blinding clays; and pinpointing problem areas on heap leach pad surfaces.

Feb 10, 2021

By Frederick Bird

This paper is based upon a review of studies of mostly Canadian mining companies in Chile, northern Canada, Tanzania, Guatemala, Ghana, Sierra Leone, and the Democratic Republic of Congo. In spite of often well-meaning efforts most mining firms produce wealth in developing areas that largely benefit those immediately involved, sometimes neighboring communities, and often those in the governing strata. Typically mining takes place in enclaves and fosters enclave development, rather than the kind of inclusive wealth development favored by the recently UN published Inclusive Wealth Report. One way by which mining operations can foster more inclusive wealth development is to adopt much broader approaches towards the construction of the various physical and social infrastructures ? roads, water, electricity, health services, schools, security ? required for their own operations by collaborating with diverse regional, provincial, and/or national agencies and businesses to develop these infrastructures for larger populations and areas beyond the immediate sites where they are operating. Established mining firms can also foster more inclusive wealth development by establishing more formal, collaborative relationships with artisanal miners.

Aug 1, 2013

The Waste Isolation Pilot Plant (WIPP) is adding a third fan to operate in parallel with, and supplement, its two existing main fans. An engineering analysis conducted in 1995 identified the need for improved system availability and efficiency. The WIPP, located near Carlsbad, New Mexico, is a U.S. Department of Energy (DOE) Carlsbad Area Office facility designed to permanently dispose of U.S. defense-generated transuranic waste in a deep bedded salt deposit. Engineers at the WIPP performed a feasibility analysis for either modifying, supplementing, or replacing its two main mine fans. Since the centrifugal fans were installed in 1988, multiple operational and performance concerns have been identified. A comprehensive engineering study was conducted (K. McDaniel, et al., 1997) to: identify and quantify operational concerns, evaluate possible alternatives, and recommend an optimum solution. The study indicated that adding a third single-duty centrifugal fan similar to the two existing fans, and equipping that fan with Inlet Van Controls (IVCs) was the best choice. This alternative provided the most desirable combination of operational readiness, and improving system performance. The fan installation project accommodates several operational and scheduling constraints. WIPP is scheduled to receive waste in May 1998. This milestone is proceeded by an operational readiness review. Fan installation could not be allowed to compromise the WIPP's ability to declare facility readiness and had to minimize operational disruptions during the system tie-in. All engineering for the project is completed and physical modifications started in July 1997. The project will be completed in early 1998.

Jan 1, 1998

By D. Harrington

Before the present century there existed a fairly persistent demand for the establishment of a Federal Department of Mines, but relatively little was done about it until a considerable number of very serious coal-mine disasters in 1906, 1907, 1908, and 1909 created what might almost be termed a national scandal and virtually forces the Federal. Government to take action to try to solve the problem of the cruse and prevention of such disastrous occurrences. Instead of a Department of Mines, the mining people had to accept a bureau, which was created on July l, 1910; and while the Bureau of Mines was given numerous functions, unquestionably the promotion of safety in the mineral industries was and continues to be one of its main "jobs." The Bureau's organic act was approved in 1910 and amended in 1913. Both the original and amended acts indicated that promoting; the health and safety of the mine workers constituted the chief function of the Bureau, and that this was the construction placed on its activities by those put in charge in 1910 is shown very definitely by the fact that as soon as the Bureau came into existence on July 1, 1910, both health end safety activities were started in its Mine Accidents Division. Before the end of the first fiscal year (June 30, 1911) 6 mine safety stations had been established in various parts of the United States, add 6 nine safety cars had been put into the field; by October 1910 first-aid-training work was being done in mining regions. The Bureau eras able to function so promptly in its safety work largely because sections of the Geological Survey, which had been doing some coal-mine safety work since 1907 or 1905, were transferred into the Bureau when it began to operate in July 1910. On October 30, 1911, a national First-Aid Meet was held at Pittsburgh, Pa., at which first aid and mine rescue were demonstrated. During the fiscal year 1910-11, the first year of the Bureau's existence, 509 persons were given certificates indicating completion of the Bureau's training course in first aid.

Jan 1, 1939

By E. O. Jacobs

A coupled solid and rock fracture mechanics model is used to analyze the blast driven fracture propagation phase, predict propagation rates, and directly measure shockwave and particle velocity. The study incorporates quasi-static pre-stress conditions for different depths below the surface. The scaled experiments include dynamic material properties and quasi-dynamic fracture mechanics which are shown to significantly affect the fracture propagation. The study was performed using three-dimensional cube-type laboratory models fabricated from Polymethylmethacrylate (PMMA). The test cubes are loaded with explosives and resulting fracture networks are studied. The dynamic evaluation of the spatial crack system is monitored using a high speed image camera. An experimental model set-up is designed to indicate the pre-stress effect on deep borehole blasting and is shown that the pre-stress conditions have a decisive influence on fracture profiles and orientation. It is found that shockwaves rapidly exceed the slower dynamic fractures and a majority of cracks occur due to detonation pressure. Experimental testing using different parameters validate that explosive fracturing can predict the outcome of fracture and crack propagation in any rock type with known material properties. This can be accomplished under great stress conditions deep below ground surface. The experimental study results can be applied to a variety of industries such as mining and quarrying, tunneling, oil and gas, and construction.

Feb 23, 2014

By H. R. Huffman

"This paper reviews the history of iron powder production, and outlines the varions production methods. The uses of iron powder and the reasons for its use are also covered. The paper concludes with a look at future trends in powder metallurgy.INTRODUCTION TO POWDERSTHE IRON POWDER INDUSTRY is enjoying a very rapid growth. The annual consumption of iron powder is now at the 100,000-ton level, twenty times higher than it was at the end of World War II, and the yearly in-crease bas been almost consistent at 20 per cent. This is expected to increase, bringing the tonnage to 200,-000, or even (according to some experts) to 270,000, in 1970. In any event, powder metallurgy is expanding at high speed and making an important impact on the production of iron and steel products. Some indication of the faith in the future market may be indicated by the commencement of three new powder production plants in Canada with a total capacity of 136,000 tons annually."

Jan 1, 1969

By Jerry M. Riggsbee, John H. Weber

INTRODUCTION The Washington Metro is a 98 mile rapid transit system that will serve the District of Columbia, southern Maryland, and northern Virginia. The construction work herein described relates to Section B-1 of this system. The contract for this work was awarded by the Owner, The Washington Metropolitan Area Transit Authority, to a joint venture doing business under the name of Ball-Shea-Norair. The partners in this venture were Gordon H. Ball, Inc., Danville, California; J. F. Shea Company, Inc., Walnut Creek, California; and Norair Engineering Corporation, Washington, D. C. The bid price for the project was $33,741,524 with a contract duration of 910 calendar days. Notice to proceed was issued January 5, 1970. The present modified price for the work is $36,866,000 with completion anticipated in July 1974. (About 1,638 days elapsed time.) The work to be done consisted essentially of construction of 3,490 linear feet of cut-and-cover track with side platform, and 600 ft cut-and-cover arch shaped subway stations. Stations are located in Judiciary Square and Eighth & G Street, N. W., areas. Decking of excavation in street areas, maintenance of traffic and utilities, vent and fan shafts, underpinning of court buildings in Judiciary Square and the Smithsonian National Portrait Building, and an electrical substation were included in the contract. Stations were constructed of cast-in-place concrete.

Jan 1, 1974

By Brian Patrick, Norman Bell, Mark Schoenfield, Thomas Weber, Dietrich Gross

"The reduction of carbon dioxide emissions and the resultant greenhouse gas affect is hampered by the fact that all fossil fuels contain copious quantities of carbon. Process tweaking can keep the amount of carbon dioxide to a minimum but cannot significantly reduce the amount of carbon dioxide generated. The very nature of utilizing fuels requires that they be burned to release the heat required for the various processes. Reduction of metal oxides to manufacture or modify pure metals, generation of power, transportation and many other forms of fuel usage result in much of the generation of man made carbon dioxide. Oxyfuel is a unique contributor to carbon dioxide emissions. While creating higher concentrations of carbon dioxide the total volume of carbon dioxide generated is reduced. This paper will examine the unique characteristics and potential of oxyfuel that make the generation of lower volumes of carbon dioxide possible.Nearly ten years ago a commercial application of oxy-fuel was installed at Jupiter Aluminum Company in Hammond, Indiana. This process was funded and developed by Dietrich Gross CEO. This aluminum remelt facility now runs completely on oxy-fuel and has continuously for over ten years. This has reduced the melt rates to as low as 750 BTU per pound in continuous melting periods."

Jan 1, 2009

By G A Brown

Environmental legislation is changing rapidly throughout Australia at the present time, and with that change comes additional responsibilities for the mining and petroleum industries. Among the many changes that are being made are increased penalties for both criminal and accidental environmental impairment. The defences for criminal offences are limited and for other offences the laws may impose strict liability - in effect the offender is guilty until proven innocent. Mines may be included under contaminated land legislation, creating additional liabilities for clean-up, rehabilitation and long-term management. It is not unknown in Australia for the value of a mortgaged property to be less than the amount of the environmental liability acquired by a mortgagor in possession due to contamination of the site. An essential part of the management program for resource projects is now the regular conduct of an environmental audit, the results of which assist in the management of the legal and financial liabilities facing company directors and managers. The audit can also assist with negotiations with government agencies, staff, unions, insurers, Aboriginal and other community groups. An environmental audit may also help to ensure that companies are claiming the maximum allowable deductions for environmental works under the tax laws, and provide evidence in support of such claims. Environmental legislation affecting resource industries Environmental legislation in Australia is changing rapidly and can impose massive constraints, substantial administrative costs, and considerable liability on directors, managers and the corporation. Pollution control legislation Every State and Territory of Australia has a range of pollution control legislation contained in either individual acts relating to air, water, noise and land, or embodied in a single environment protection act. Pollution control legislation provides a critical management baseline for resource industries throughout Australia, often requiring the full-time attention of an environmental manager or an environmental department. In general, it is an offence to discharge effluents into water, or emit gases into the atmosphere above prescribed limits, cause noise above a regulated level, or contaminate land without a licence. A licence determines how much of a substance can be discharged, the location, the receiving environment, the quality, and the time at which discharges can be made or noise can be caused. Planning legislation Planning legislation controls where a project is located, how it will be constructed and operated, how large it is allowed to be, and what will happen once the project is completed. Development consents or approvals will generally contain a range of conditions controlling the preparation of the site, the construction of the facility and the way it is operated throughout its expected life time. Resource projects may be regarded under legislation as scheduled or designated developments requiring special treatment during the decision-making process. Under planning legislation, it is usual for resource projects to be subject to an environmental impact assessment process. Resource legislation Resource legislation specifically covering mining and petroleum in Australia, also contains requirements regarding protection of the environment during exploration for and extraction of minerals and oil. A mining or petroleum production lease usually contains numerous conditions regarding protection of the environment and rehabilitation of the site during and after the life of the extractive process.

Jan 1, 1994

By Ronald Ticona

Generally, the drilling and blasting operation are managed independently to the processing plant outcomes. Therefore, the technical segmentation to determinate the ore drill and blast designs do not include processing plant rock properties such as Bond Work Index, Axb, Drop Weight Index or other. This work describes the case study of a copper mine in Peru, which, together with its strategic partner ORICA, have implemented projects focused on optimizing mine fragmentation. The year 2021, mine operation according to its mine plan would have a significantly increased SAG mill hardness, which would impact directly on copper concentrated production. An integrated strategy from mine to plant has become necessary to maintain the production levels.

Feb 6, 2023

By Kevin M. Ansdell, Irvine R. Annesley, Christine L. Mckechnie

The U-Th-REE mineralization at Fraser Lakes Zone B is hosted by granitic pegmatites and leucogranites, which lie along the deformed contact between Paleoproterozoic metasedimentary gneiss of the Wollaston Group and Archean orthogneiss, approximately 25 km from the southeastern edge of the Athabasca Basin. The pegmatites/leucogranites are subcordant to concordant with the regional foliation and are concentrated within a northeast-plunging antiformal fold nose, the study area, which lies west of Fraser Lakes. The mineralized pegmatites/leucogranites in the western part of the study area (Group A) are typically enriched in U (± Th) with Th/U ~1, and contain uraninite, thorite, zircon, and allanite. Those intruding the central part of the study area (Group B) are generally enriched in Th and LREE, with Th/U >2, and contain monazite, thorite (commonly U-enriched), and zircon. The pegmatites and leucogranites in Group A tend to be slightly enriched in SiO2 and depleted in TiO2 relative to those in Group B and are interpreted to represent more evolved crustal melts. Both groups are peraluminous and show varied chemistry. Partial melting (~850ºC and 9 kbar) of a metasedimentary rock-dominated source, entrainment of accessory minerals as xenocrysts, and assimilation-fractional crystallization processes combined to enrich the granitic pegmatites/leucogranites in U, Th, and REE elements. Transfer of melt from the source region to the crystallization sites was assisted by deformation within and along major structural zones, such as the folded Archean-Paleoproterozoic discontinuity. The character of mineralization and structural control in the study area is reminiscent of the alaskite-hosted deposits at Rössing, Namibia.

Jan 1, 2013