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By Grażyna Dzik, Adam Mirek, Krzysztof Król

The Upper Silesian Coal Basin is located in the area of the Upper Silesian Syncline and belongs to one of the most complex tectonic units in Europe. It occupies 5,650 km2. In 2020, there were 20 hard coal mines operating in the area. Seismological research in this area consists of observation of precursors/symptoms of shock generation and understanding of their effects. Studies (Teisseyre R. 1972, Mutke G. & Stec K. 1997, Stec K. 2007, Dubiński J. & other 2010, Idziak A. 2010) of complex impacts of rock mass provided a background for determining the conditions for the formation of exploitation and regional seismic shocks. Issues related to tectonic and exploitation stresses, successive extraction of coal seams at higher depths, operation in the vicinity of fault zones, often complex geological and organic conditions result in the activation of a discontinuity surface due to stress caused by deformation of rock layers, which, as a result, causes the emergence of strong shocks above 107 J. The article was based on analyses of extraction value, high-energy shocks, both of mining and tectonic-mining (so-called regional shocks) origin, against the background of changing operating conditions, which, as a result, creates an image of periodically changing seismic activity and location of strong shocks. Observation results show that, with an increase in exploitation depth and declining extraction, the number of strong shocks caused by tectonic stress (107 - 109 J) and exploitation stress (≥105 J) has been steadily increasing over the last 25 years.

Apr 26, 2022

By G. T. Lineberry

There is a critical need for effective instructional materials at the university level and for an upgrading of mine safety and health in the mining engineering curriculum. A fundamental approach to mine safety and health is recast into the familiar 3 E's: engineering, education, and enforcement, in that order. Each is briefly reviewed and their interdependence emphasized. A unique philosophy for successfully integrating safety and health principles into the mining engineering curriculum is offered. The concept of textbook ?tailoring? is discussed and defended, permitting rapid assemblage and synthesis of existing educational materials. Final recommendations are made for a u, comprehensive approach to mine safety and health education in the undergraduate curriculum.

Jan 1, 1987

By Stephen A. Orr

Underground mining is a dynamic art and science with a diverse set of design, production, and economic criteria that must be considered before selecting an optimal method to extract the ore. While all methods can be technically classified as either self-supported, supported, or caving, the multitude of subsystems and existing variations bear witness to the fact that each orebody is unique and, as such, justifies an individual approach to optimize mineral extraction. In this sense, underground mining is an art. The ability to evaluate the unique characteristics of each ore body and utilize sound engineering principles to design the optimal system constitutes effective method selection. The task by no means ends at this juncture, however. Subsequent implementation requires an ability for modification. Very rarely are all the facts available to make a concrete decision prior to development of the resource. As a result, the risk of a wrong decision can never be eliminated. This requires a significant degree of flexibility with each method. Each unit of exploration, development, or exploitation work contributed to a deposit enhances knowledge of the ore body. The best mining methods are those that correctly account for the known parameters but provide an allowance for change at minimal cost and adapt to unanticipated conditions.

Jan 1, 2008

Introduction The science of geometallurgy requires that ore characterization be performed holistically, that is, with consideration of ore quality on plant performance and product quality. Geometallurgy, by definition, requires knowledge of geology, mineralogy, extractive metallurgy and pyrometallurgy. Examples of the ore characterization challenges for the geometallurgist in the production of iron ore pellets from low-grade Proterozoic iron formation are presented here. Ore Characterization Ore characterization, the quantifying of mineralogy, grain size and the texture of ores, is an often overlooked tool in improving process efficiency. Some mineral related problems are not unique to the production of iron ore pellets; e.g. the problems caused by expanding clays in flotation. The negative impact of carbonate minerals in the ore on pellet productivity and pellet quality are unique. The long and complex geologic history of Precambrian iron formations contribute to modifications of grain size and the introduction of complex textures.

Jan 1, 2007

By B. V. Clingan

A practical application of recent design concepts makes it possible to design a column cell to fit a specific set of conditions. The design and operating parameters Of a column cell installation that replaced a conventional two stage copper flotation cleaning circuit at MAGMA COPPER COMPANY, SAN MANUEL, ARIZONA using these design concepts is described. A survey of other mineral processors using column cell technology was conducted. The results of this survey will also be discussed.

Jan 1, 1987

By S. C. Gambrell

The practice of roof bolting in world-wide mining activities is very well known, having been used extensively for over 50 years. The theory of roof bolting, however, is extremely complicated, and only recently have investigators attempted to explain the theory. Discussions of the mechanics involved usually originate with actual experience gained in the use of roof bolts. The use of roof bolting in mines has grown dramatically during the period after World War II. Other scientific techniques have emerged in mining research in the same period. Included in these techniques is the study of rock mechanics, which has now developed into an impressive research effort. Various means of analysis have been utilized in rock mechanics, most of which reduce rock to an isotropic, homogeneous medium that could be easily analyzed. Because of the inherent nature of rock, direct research methods frequently are not certain to provide satisfactory results, whereas indirect methods must idealize a given set of conditions in order to be useful. One of the indirect research methods is the photoelastic technique, the theory of which is widely known and needs no elaboration. This technique has been used extensively to examine the state of stress around underground openings of various shapes in certain types of strata, and under various configurations (1,2,3,4,5). Much of the theory used now in the design of underground openings is based on photoelastic evaluation. Unless rigorously applied, how- ever, the photoelastic technique is at best a qualitative means of evaluation. It is useful, however, for unusual examples which can be more or less easily analyzed to obtain the overall state of stress which could not be determined by other means. Little work has been done in the photoelastic analysis of rock bolting, mainly because direct research techniques have proven useful.

Jan 1, 1970

By Jeffrey D. Thatcher, Debra W. Struhsacker

With the burgeoning development of precious metals heap leach mining projects throughout the country regulatory agencies are beginning to take a closer look at the short-and long-term environmental consequences of heap leach mining. This increase in regulatory review is occurring on federal, state and local levels, and is affecting both large- and small-scale mining developments. Small-scale mining developments are receiving especially critical regulatory scrutiny because in the eyes of some regulatory agencies, small developers lack the credibility automatically accorded to major mining companies. This is due in part to a bad image of small miners based upon past environmental problems and permit violations caused by a few, small operators. The proponent of a small mining development thus faces special problems during the project permitting process, and must convince the regulatory authorities of his company's ability and commitment to plan, develop, and decommission a mining operation in compliance with environmental regulations. Not only must the small developer have a thorough understanding of the regulatory requirements affecting his project, he must also devote considerable effort to careful internal planning in order to produce a well organized approach to project permitting. The importance of proper planning cannot be overstated. Project planning is key to convincing the regulatory agencies that the small miner is capable of developing a viable project. More- over, the economics of a small mining project demand permit acquisition at modest cost and in a timely fashion. A well planned permitting effort will thus ensure that permits are received within budget and on schedule. This paper will review the federal, state, and local permitting requirements for heap leach projects, and the variability of these requirements from state to state. The environmental assessment process for projects developed on public lands, and the acquisition of zero- discharge water quality permits, air quality permits, and local special use permits as they apply to small mining developments will be discussed. The paper will conclude with a review of project decommissioning and cyanide neutralization requirements and their implications for small-scale heap leach projects.

Jan 1, 1987

By R. E. MacDougall

Very few mineral properties spend their entire lifespans from discovery to depletion in the hands of one owner. More likely, properties will have several owners, and partial interests may change quite often. Similarly, mineral companies are bought and sold with frequency, in recent years at what appears to be an accelerating rate. The reasons for selling a property can be manifold -need for additional capital in other parts of the business, need for development capital, realization of a large gain at a perceived high point in the market, pessimistic commodity outlook, retirement of principals, or resolution of estate problems. Regardless of the reasons for a sale, there are specific steps that logically follow. Spruce up the business, package the information, market the property, negotiate the terms, close the sale, and make sure it stays sold. Adherence to certain very basic ground rules in property sales can maximize the profits and minimize the effort.

Jan 1, 1990

By R. L. Virta

Common clay is a natural, fine-grained material composed of hydrous aluminum silicates. Shale is a laminated sedimentary rock that is formed by the consolidation of clay, mud or silt. Production About 160 companies produced common clay and shale in 41 states. In states not reporting production, common clay and shale probably was mined and sold for construction applications by companies not participating in the U.S. Geological Survey’s canvass of producers.

Jan 1, 2005

By D. C. Myntti

An open pit mining equipment maintenance program, in order to be successful, must have many active segments covering the full range of equipment selection, trained personnel, repair facilities, preventive maintenance programs, warehousing, interdepartmental cooperation, paperwork and effective communications. The mine maintenance program is required to protect company assets Which are units of equipment generating revenue. The program should result in reduced unscheduled equipment downtime, increased equipment productivity rates, and decreased unit operating costs. Current maintenance problems; maintenance effectiveness and future projections on equipment maintenance are discussed. Equipment maintenance is big business and the maintenance department is a full-time partner in the mining venture.

Jan 1, 1978

By Lukas Walder, Roland Arnold, Raphael Zuber, Richard Gradnik

This paper presents the construction of the ventilation shaft for the single-tube, doublelane Kramer tunnel. The project is located in the Federal State of Bavaria, Germany. This road tunnel, which has been under construction since December 2019, is the key component of the western bypass of the town of Garmisch-Partenkirchen. Once completed, it will relieve the town’s central district from enormous volumes of traffic. The contractor is the joint venture named ARGE Kramertunnel consisting of BeMo Tunnelling and Subterra. The whole project will be completed and handed over to the project owner, Staatliches Bauamt Weilheim, in 2023. The opening of the entire bypass section including the tunnel to traffic is planned for 2024. The tunnel, with a total length of 3,609 m (2.24 miles) and an estimated cost of EUR 178 million incl. VAT (US-Dollar 201 million), is designed as a single-tube, double-lane structure with one traffic lane for each direction of travel. The safety issue that exists for singletube tunnels is solved by a parallel escape tunnel passable for vehicles. For tunnel ventilation, an intermediate shaft has been designed with a depth of approximately 90 m (295 feet) and an inner diameter of 4.5 m (14.8 feet). All tunnels and ducts are excavated according to the principles of the New Austrian Tunnelling Method (NATM). The geological and hydrogeological conditions, the change in the profile (from round to square geometry), and also the shaft being located at a high elevation presented a demanding technical and logistical challenge. The site arrangement with the pit bank was located in a cut, the slopes of which had to be stabilized with shotcrete and soil nails. This excavation was carried out from the fall of 2020 to the beginning of 2021 because construction operations had to be completed outside the nesting period of protected birds.

Jun 13, 2023

A methodology has been developed and demonstrated to be effective in reclaiming surface-mined land for a forestry post-mining land use. The forestry reclamation approach (FRA) has been applied, almost exclusively, to flat or gently rolling surfaces. One of the primary steps in the FRA is to loosely grade the top 1.22 m (4 ft) of soil or substitute root growth medium to avoid excessive compaction. Concern has been expressed by regulators and the public that loose grading on steep slopes (i.e., greater than 23°) could lead to slope failures, which is one of the issues that the Surface Mining Control and Reclamation Act of 1977 (SMCRA) sought to correct. A field investigation was conducted at a steep-slope contour operation in eastern Kentucky to test the applicability of FRA in this setting. Final grading was performed according to FRA standards. The surface consisted of two distinct substitute rooting media. One was unweathered gray sandstone and the other was a combination of gray sandstone, brown sandstone, and topsoil. A variety of native hardwoods was planted following the FRA guidelines. The slope was instrumented with 70 survey monuments to monitor for mass movement. The reclaimed spoil was also characterized using bulk density and penetrometer resistance methods. The characteristics of both spoils are similar to those observed on flat to rolling surfaces where the FRA has been used and, after one year, approximately 70% of the trees had survived. During this first phase of investigation, there has been no major mass movement of the slope and slope stability analysis indicates that the application of the FRA has little impact on the overall stability of the slope. Mining Engineering, 2011, Vol. 63, No. 12, pp. 55-62. Official publication of the Society for Mining, Metallurgy and Exploration, Inc.

Jan 1, 2011

By G. Hoffman

Sustainable development has brought social, environmental and energy efficiency concerns together with management and governance of natural resources. Cement manufacturing, an energy- and natural resource-intensive industry, is adapting to meet sustainable development goals. Emission standards for cement plants and increasing energy costs have lead to changes in the use of natural resources and recycled materials. Utilizing pozzolans or supplementary cementitious materials (SCMs) as mineral admixtures in blended cement or as a substitute for cement in concrete lowers energy costs and CO2 emissions. Although the western U.S. is rich in natural pozzolans, artificial products, particularly fly ash, have greater use as mineral admixtures. Pozzolans and SCMs have many beneficial properties, such as preventing alkali-silica reactivity, a common problem in the western U.S. Barriers exist for mineral admixtures in the cement and concrete industries because of past inconsistencies in quality or availability. New environmental regulations on the primary industries producing artificial mineral admixtures could adversely affect the quality and quantity of these materials in the future.

Jan 1, 2009

By Richard H. Johnson

White Pine Copper Company, a subsidiary of Copper Range Company located in Michigan's Upper Peninsula, mines a Precambrian sedimentary deposit containing finely disseminated chalcocite, native cop- per and native silver. Silver occurs predominately in certain strata and presently provides a mill head averaging 0.25 ounces per ton. This technical publication traces the development of silver recovery at White Fine beginning in early 1961. White Pine refined copper contains an excess of silver over and above that required to impart Lake Copper properties. The copper does not require electrolytic refining to meet industry purity requirements, nor is there sufficient silver to justify electrolysis.

Jan 1, 1970

By Arvid E. Anderson

The paper describes the unique operating features of the Lebanon Concentrator Plant wherein both magnetic concentration and froth flotation are used. Chalcopyrite is selectively floated by the use of dual collectors, Aerofloats and secondary butyl xanthate. Both potassium ethyl xanthate and sodium isopropyl xanthate (dual collectors) are dissolved and emulsified with pine oil for the flotation of the pyrite. Sketches describing the plant operations are presented and plant operating metallurgical results obtained are also given. The optimum production of minerals by the froth flotation process is normally achieved [ ] smooth operating conditions, The process, because of its many variables, becomes an art as well as a science. Therefore, any phase of the operation which will aid the operator in his control of the numerous variables will help produce a smoother operating plant, One of the most important variables which the operator deals with is the addition of reagents, These are usually costly items and should be used discretely with minimum amount of waste, The danger is that ,this emphasis may reduce the reagent amount to a point below that required, or, on the other hand an excessive amount is added, Both conditions usually yield poor results. The drea of the metallurgist is to provide the operator with the tools enabling him to produce a good mineralized froth at all times. Normally the operator has no control concerning the type of reagents which he must use. This has usually been worked out for him in the laboratory and by plant-scale tests. He does have limited authority to control the amounts of the reagents at his disposal. This, I believe, is as it should be. However, the operator should be provided with the best combination of reagents for his particular job. The providing of this combination of reagents for his particular job, The providing of this combination is often difficult, yet it is very important in order to yield good results, With this in mind, the dual collector idea was introduced for the selective flotation of chalcopyrite, and also later for the flotation of pyrite at the Concentrator Plant of the Bethlehem Cornwall Corporation in Lebanon, Pennsylvania, Supplying several types of collectors has given the operator an additional effective tool, even though great variations are encountered in ore tonnage treated and in ore composition, This paper deals with the use of the dual collectors and with the addition of the reagents in the form of a pine oil emulsion, or more accurately, a pine oil suspension. It is hoped that other operators may find the ideas helpful. There does not seem, to me, to be definite scientific fact which would substantiate the necessity for the use of dual collectors. However, in actual operations, the metallurgical results at Lebanon became more uniform with the use of dual collectors, I look upon it as an "insurance policy" which greatly aids the operator during those periods when he is having trouble, One theory has been advanced, i.e. one collector has a greater tendency to float the coarser minerals, whereas the other one may float the finer ones. Consequently, a combination of the two collectors will result in optimum recoveries, There has been some evidence that this is true, but it is not conclusive, on the other hand, the use of a xanthate-pine oil suspension (or emulsion) should speed up the surface reaction of the collector with the sulfide minerals, result¬ing in more uniform flotation, This has definitely happened in our particular case. A more interesting unexplainable observation has also occurred; i.e., the xanthate solution does not appear to lose its strength as rapidly when it is in the form of an emulsion (or suspension), This was first observed when a 50 gallon drum of a 20% ethyl xanthate solution was taken to Wilmington, Delaware, for a laboratory test, using a homogenizer to produce the xanthate-pine oil emulsion. Upon arrival, the drum of xanthate had developed a considerable internal pressure, The relief of this pressure was accompanied by a strong odor, When the emulsion was returned to Lebanon for the plant test orders were issued to release the pressure prior to emptying the emulsion. Nopressure had developed within the drum and there was no unusual odor present, Since this time it has been observed that xanthate pine oil suspensions have greatly decreased the possible decomposition of the xanthate solutions. In fact, suspensions have been exposed for more than a month without apparently effecting their reactions in the flotation plant. On the other hand, we found that the regularly mixed concentrated xanthate solutions, after standing for several days, did not give the same results as the freshly made ones. This effect was greatly reduced by the use of xanthate pine oil suspension (or emulsion)

Jan 1, 1958

By E. Topuz, C. Patrick

Longwall face-to-face transfers can cost more than $100 per minute in lost production potential and $100,000 for personnel and supplies. Such high costs make extensive planning and control of the transfer process a critical necessity for the economic feasibility of longwall operations. Operations research techniques are used for the analysis and modeling of longwall face-to-face transfers. Transfer data has been collected from companies who operate, over 35%, of the total US longwall faces. Comprehensive sequence networks of existing longwall transfers were developed; simulation was used to generate models of transfers under Carving conditions; and the economic feasibility of tine-cost tradeoffs in the transfer procedure was investigated.

Jan 1, 1994

By W. J. Atkinson, E. M. Anderson

FOREWORD This paper is based on the authors' experience gained in the environmental assessment of major uranium projects in the former Department of Science and the Environment and Department of Home Affairs and Environment of the Australian Government. The authors gratefully acknowledge assistance received from colleagues within the Department of Home Affairs and Environment in the preparation of this paper. Special thanks go to Mr K.E. Thompson of the Department's Environment Division for his valuable comments and criticism. The views expressed in the paper are those of the authors alone and not the Australian Government or Dames & Moore. INTRODUCTION Uranium has been mined in Australia since 1954. A number of small scale mining and milling operations were active in the Northern Territory, in South Australia and in Queensland in the late fifties and early sixties. However, in the late sixties there was an increase in exploration activities in the expectation of an upsurge in world demand for uranium Substantial new resources were delineated in the Northern Territory, Queensland, South Australia and Western Australia. The most significant deposits were located in the Northern Territory, in what is called the Alligator Rivers Region located approximately 200 km east of Darwin. The Region is in the latitude of 13° South and thus lies within the Australian tropics (Figure 1). It consists of approximately 2.3 million hectares of natural wilderness containing much spectacular and attractive scenery. The area is noted for its abundant wildlife, particularly the waterbirds that gather on the flood-plains. Much of the vegetation is diverse and interesting. The Aboriginal population still maintains elements of the traditional way of life, and the spectacular Arnhem Land escarpment contains many of the best surviving examples of Aboriginal rock art. Numerous rich archaeological sites provide evidence of continuous human habitation for tens of thousands of years. Climatically, the Region is of the tropical monsoon type with a dry season from may to September and a "wet" from November to March. High intensity short period rainfall is characteristic, and the average annual precipitation is in the order of 1 350 mm. The monthly mean temperature ranges from 25° to 30°C throughout the year. The development of regulatory controls on uranium mining in the Alligator Rivers Region has been affected by the political status of the Northern Territory. While Australia is a federation, established as an independent self-governing country in 1901, it was not until 1978 that the Northern Territory became to any real extent self-governing. Prior to 1978, the Territory was administered through a special department of the Commonwealth (ie. the Federal Government). Under the Northern Territory (Self Government) Act 1978, administrative powers similar to those possessed by the Governments of the six founding Australian states were provided to the Territory Government. However, the Commonwealth government did not transfer to the Territory all such powers and functions, and in particular there has been, since 1978, a dual role for the Commonwealth and Territory Governments in the regulation of uranium development. Details of this role are provided later in this paper. RANGER URANIUM INQUIRY By 1973, major deposits had been discovered in the Alligator Rivers Region at Nabarlek, Ranger, Koongarra and Jabiluka. The estimated reserves and mine life expectancy of these deposits are given in Table I. Other radioactive anomalies have also been identified in the area but, as yet, they have not been delineated or evaluated. [ ] In 1974, an agreement was signed between the Commonwealth Government and Peko Mines Limited and the Electrolytic Zinc Company of Australia Limited for the joint development of the Ranger deposit. In July 1975, the Government announced a Commission of Inquiry under the provisions of the Commonwealth Environment Protection (Impact of Proposals) Act 1974, into the proposed Ranger development. The inquiry was known as the Ranger Uranium Environmental Inquiry or more commonly, the Fox Inquiry after the presiding Commissioner, Mr Justice Fox.

Jan 1, 1981

By W. J. Turbeville

The subject of this discussion is timely. The U.S. phosphate industry is suffering the throes of depression. It's plight is a matter of widespread concern. The future role of the U.S. industry in world markets is of particular interest. If we should prognosticate phosphate supply-demand on the basis of recent history, we would face a puzzling choice of scenario. In 1980, perhaps the best year ever for U.S. phosphate, 54.6 million metric tons of phosphate rock entered the market place. Of this, more than half was exported -- divided almost equally - as rock or phosphate fertilizer. During the last half of 1981 the situation had begun to change.

Jan 1, 1983

By R. Marrill

Mining is a complex and intensive industry. Extracting raw material with different shapes, sizes, chemistry from the earth?s crust and transform them into a standardized and high quality final product is a big processing challenge - which involves energy and control on large scales. Not only is the physical work challenging, the mining industry today is facing unprecedented challenges: Decline of mineral grade and reserves, cost escalation for new developments and modernization, regulations, safety, lack of skilled people, and market uncertainty are the new constant. It is clear that process control and management of electrical power will be of increasing importance to the recovery rates the mine will achieve. The objective of this paper is to provide a quick vision about future trends and evolutions in technology related to these fields and their impact on Electrical Safety and Control of the mineral recovery. The paper will cover trends in safety, energy management and efficiency, communications of data, control room evolutions, plant integration, other control technologies, and we will examine how these technologies provide information and the benefits of aligned reporting systems to address current industry challenges. More than just the trends or breakthrough concepts, current technologies are available today that can be applied in the mineral recovery operations now to help overcome anticipated future challenges will be presented later in this document. Finally, a brief discussion to look at some real tools to help make real time changes to the process while maximizing recovery and optimizing cost.

Feb 27, 2013

By John B. Spencer

Earlier this year, Simplot Phosphates achieved a safety milestone at its Vernal, UT phosphate operations. In March, the entire operation reached achieved seven years without a lost time accident. And the mine operations at Vernal reached the 1 million hours benchmark without a lost time accident. This million hour achievement has been 19 years in the making. This achievement reflects the mine’s strong attitude towards safety, the company said. Safety is an integral part of its culture and requires diligence and considerable work. Attention to even the smallest of details cannot be allowed to slip. This is a record Simplot Phosphates said it hopes to improve on every day.

Jan 1, 2004