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By Wils L. Cooley

Although electric utility companies have been active in grounding and bonding within substations, the mining engineer or mine electrical engineer is not involved to the extent that he can be fully up-to-date on the most effective practices for substation construction. The coal mine power system is grounded in a fundamentally different way from most other industrial power systems and is subject to considerable Federal and State regulation. At this time, there is little information that is directly applicable to the mine situation, especially if the substation must be built in an area of limited size or in low-conductivity earth. The objective of this guide is to provide specific engineering information to the mining; industry. Using as little theory as possible, it was written to be general enough to cover most substations, but specific enough to provide direct help with each substation. It will attempt to recommend practice that is in agreement with present Federal rules and regulations.

Jan 1, 1980

By AIME AIME

TO THE AMERICAN MINING CONGRESS. AMERICAN INSTITUTE OE MINING ENGINEERS. MINING AND METALLURGICAL SOCIETY OF AMERICA. The committee that makes this report was appointed at the meeting of the American Mining Congress, at Denver, Colo., in. November, 1906. The appointment had in view the drafting. of a law for the regulation of quarrying and metalliferous mining under the police laws of the States, with the hope that the uniform adoption of such a law could tend to reduce the number of accidents in mining. Since its. appointment, the committee has had' under serious and continuous consideration the matter with which it was charged. At the meetings 0f the American Mining Congress in 19o7, 1908 and 1909, it reported progress. At the meeting in 1909 it was authorized to present its report not only to the American Mining Congress, but also to the American Institute of Mining Engineers and the. Mining and Metallurgical Society of America, and to present its report in printed form during the interim between meetings of the American Mining Congress. The committee collected from the officials of the States of the Union copies of their mining laws. With the assistance of the Engineering and Mining Journal copies of the laws 0f Great Britain, the Transvaal, New South Wales, Victoria, Queensland, Western Australia, Tasmania, New aland, and certain European countries were also obtained. These laws were subjected to careful study. The first publication of the committee was a summary of the more important metalliferous mining laws 0f this country. Upon the basis of the existing laws of the States of the Union, Great Britain, and the English speaking colonies, a tentative draft. was prepared and printed in limited number in 1909, for convenience in securing the advice and criticism of a considerable number 0f persons engaged in the mining industry. In this way valuable suggestions were received. At the request of the chairman of this committee, Mr. Frederick L. Hoffman, statistician of the Prudential Insurance Company, of Newark, N. J., summarized and reviewed the available statistics of fatalities in metalliferous mining in the United States. Mr. Hoffman's report was published in the Engineering and Mining

Jan 10, 1910

By R. Snoby

Since its introduction in 2002, the modern air jig has processed a wide array of coals throughout the world. This paper explores the reasons and justifications for the installations and provides case history performance data. Specifically highlighted are air jig plants processing metallurgical coal in Colombia, bituminous coal in the United States and India and lignite in the United States and Spain. Each installation has unique reasons to justify an air jig facility. It is important to note that not all of the justifications were based on the ?most cost effective yield?, normally a mantra for coal preparation plant designers and owners. Dry jigging of coal has long been a proven technique for upgrading coal, the modern air jig, with its improved efficiency and operating systems simply extended the range of applications. In some cases, it even allows market quality coal to be produced when no other option is possible.

Jan 1, 2009

By R Wilson, R Williams, B Freeburn

McLanahan RSS14x50 scrubber screens have individually processed over 50 Mt of Pilbara iron ore. The first stage of separation in these plants with abrasive, high specific gravity, large lumps is an extremely arduous duty with high wear rates. With the Scrubber Screen layout this occurs in the attached trommel section. The initial supply of the replaceable trommel panels were of steel-backed rubber with a service life of approx. six weeks. Site Personnel established a goal of 26 week wear life in conjunction with 100 per cent reliability and while field trials were undertaken using a variety of hardened and cast steels that demonstrated wear life to the nominated requirement some unpredicted failures still occurred. With a long evaluation time and challenges to create repeatable conditions with field testing, a purpose built test unit was designed and constructed to allow controlled evaluation of a number of materials and designs. During 2016 tests were conducted with eight different materials, of varying thickness to simulate impact conditions and a number of aperture profiles to evaluate both impact and abrasion effects. From these results two designs were selected for full scale implementation to confirm the nominated goals. This paper will present details of both testing procedures and results of all materials, as well as conclusions of successful field implementation.CITATION:Wilson, R, Freeburn, B and Williams, R, 2017. Trommel panel development for iron ore applications, in Proceedings Iron Ore 2017, pp 251–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By David A. Benjamin

At the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied prospects, claims, and mineralized sites in a 43,053-acre portion of the 51,262-acre Desatoya Mountains Wilderness Study Area (NV-030-l10) in 1985. The study area, located 50 miles east of Fallon, NV, is underlain by alluvial deposits of Quaternary age and volcanic and volcanic-derived sedimentary rock of Tertiary age. No mines or recent exploration activity were identified within the area studied. The Gold Basin area, located 1/2 mile to the south has produced 982 ounces of gold and 10,086 ounces of silver. The Cold Springs area, located 1/2 mile to the west, has recently been explored for gold-silver. Mineralization at these two areas apparently did not extend into the study area, but future mining at these areas would likely impact it.

Jan 1, 1986

By William C. B. Gates

Demolition blasting next to an active railroad can be very challenging because of track safety, blasting vibrations, potential track fouling by blast debris, and short work windows on a live track. Recently, in eastern Washington, one of the major railroad companies has been aggressively constructing a second main track to accommodate the expected increase in rail traffic of natural resource products. To accommodate construction of the second line, the railroad company used blasting demolition techniques to remove an old railroad trestle pier on the Milwaukee Road that was in the footprint of the new track bed. The trestle bridged the present rail line and flanked the track with two massive 550-ton (499 tonne) twin-columned steel reinforced concrete piers. The railroad contracted with a specialized contractor to remove the south pier using blasting demolition techniques. The blasting design presented the following challenges: blasting during live track conditions and short work windows; designing a V-notch blast pattern to ensure the pier fell away from the live track; drilling, loading, and timing of the shot; maintaining blasting vibrations at the track below 4 in./sec (102 mm/sec); maintaining ambient overpressure noise below 133 dB; control of fly rock and debris; and track protection and emergency debris removal plan.

Jan 1, 2016

By Paul C. Schmall

The link between artificial ground freezing and the mining industry stretches back more than 140 years, and across an ocean. Patented by the German scientist F.H. Poetsch in 1863, the technique is reported to have first been used circa 1862 in the coal mining valleys of South Wales. In the United States, the first ground freezing application, to a depth of 30 m (100 ft), occurred in 1888 for the Chapin Mine Co. in Iron Mountain, MO. In England in 1901, the Poetsch method was used for the first time to successfully sink two shafts through 24 to 27 m (80 to 90 ft) of wet sand and boulder clay at the Washington Glebe Colliery, near Sunderland. British mining engineer T.H. Cockin, in his 1905 Class-Book of Practical Coal-Mining, noted that, ?This method of sinking through thick beds of very wet quicksand has met with great success; it is one of the recognized methods of sinking on the Continent.? Mine shaft freezing soon became relatively common in Europe where the project could bear the cost of a major refrigeration plant construction. However, it was not until 1952 that the second North American ground freezing project was completed to facilitate the sinking of a 4.5-m- (15-ft-) diameter, 233-m- (765-ft-) deep shaft at a Potash Company of America (PCA) mine in Carlsbad, NM. Nowadays, ground freezing is used worldwide for both mining and civil applications. In small mine shafts of 3 to 6 m (10 to 20 ft) in diameter, excavations have been carried out to depths of more than 820 m (2,700 ft) within the protection of unbraced or unlined frozen walls. In fact, for deep mines, no better method has yet been established for sinking production shafts through deep, water-bearing ground. Major deposits of coal, potash and salt would still be inaccessible if not for artificial ground freezing. There are several advantages of ground freezing unique to the construction of shafts. Proper instrumentation can provide complete assurance of the integrity of the freeze to full depth prior to excavation. The frozen wall allows construction to be scheduled without evaluating the in-shaft time necessary to probe ahead, place additional sup-ports or deal with ground water. The freeze can be implemented perfectly through the soil/rock interface, which is often the most difficult geology in which to create a ground water cutoff by other methods. At increasing depths, any discontinuity

Jan 1, 2007

Being a geologist I intend describing the renaissance of the gold industry in Australia within its geologic framework; there is a geological pattern to the numerous gold projects which have been brought on stream over the past decade. We are now about midway through our third and largest gold boom which, at a peak of 7.5 million ounces is about twice the production peaks achieved in the preceding booms. From discovery in 1851 through 1870 we saw the first boom largely based on alluvial production in NSW and in Victoria at the great Ballarat and Bendigo Goldfields. The discovery of the Golden Mile in Kalgoorlie, Western Australia, underpinned the second gold boom in the period 1895 - 1915. On that basis the present boom should last through the next decade.   It has been a golden decade for Australian gold production. From less than ten mines in 1980 with production over 10 000 ounces and the largest, Telfer, with output of about 130 000 ounces we now find over 130 deposits being worked around the country today that produce over 10 000 ounces with the largest, Boddington, having an output of over 400 000 ounces. In total these mines produced an estimated 210 tonnes of gold in 1989 and we expect this year, 1990, that a new record production of between 240 and 250 tonnes will be set. This positions Australia in third place in the Western World behind South Africa #1 and the USA #2 and fourth in the world with the Russians holding second place overall behind the South Africans.

Jan 1, 1990

By F. H. Buchella, J. F. Buchanan

The San Manuel copper deposit is located about 45 miles northeast of Tucson. The concentrator, smelter, administration building, and other plant facilities are located about seven miles southeast of the ,nine area at the new town of Sari Manuel as shown on Figure 1 (Sketch).

Jan 1, 1961

By Robert G. Bottge

The Bureau of Mines investigated the availability of the land in south-central Alaska for exploration and mineral development of locatable minerals under State or Federal laws. The land ownership for an area of nearly 72.5 million acres in south-central Alaska was divided into 3 availability categories and 15 subcategories. In July 1985, 31.0 million acres of the study area were available for mineral exploration and development, 6.2 million acres were available with restrictions, and 35.3 million acres were unavailable. About 23.6 million acres in the study area are underlain by mineral terranes. About 9.9 million of the 23.6 million acres are available for mineral entry, 2.4 million acres are available with restrictions, and 11.3 million acres are unavailable. While much of the land currently classified as unavailable will be reclassified once it is conveyed to the State or to Native corporations, about 22% of the unavailable lands underlain by mineral terranes are now Federal parks, preserves, wildlife refuges, wild and scenic rivers, and military lands, all of which are considered permanently unavailable for mineral exploration and development.

Jan 1, 1986

ABSTRACTRock stresses can be modified by physicochemical processes.If rock pores allow the ingress of water and oxygen, but are not large enough to permit the exit of larger molecules of weathering products, anomalous rock pressures develop. Rock masses may also be subjected to osmotic pressures developed as water diffuses into pores and joints filled with saline water. Anomalous rock pressures may also develop as gels filling pores undergo syneresis and as salts crystallize from pore solutions.

Jan 1, 1968

By F. R. Lee

[WHEN the Bureau of Mines was established in July 1910, one of the problems immediately attacked by the new organization was the development of standard, for the design and testing of electrical equipment that could be used without fear of initiating fires and explosions in underground coal mules. Research and investigation by Bureau personnel, supplemented by the published results of similar work by European mining authorities, led to the establishment of standards or "schedules." which guide manufacturers in the design of many types of electrically operated machines and devices used in. underground coal Mining. By issuing these standards, Bureau personnel establish the requirements to be met by such equipment before it tan be approved by the Bureau of Mines as permissible for use in gassy coal mines. Every 2 years the Bureau of Mines publishes a list of equipment that leas been accepted as approved or permissible during the preceding 2 calendar years. This is done to inform the mining industry of the availability of the latest equipment for safe use underground.]

Jan 1, 1964

By F. R. Lee

When the Bureau of Mines was established in July 1910, one of the problems immediately attacked by the new organization was the development of standard, for the design and testing of electrical equipment that could be used without fear of initiating fires and explosions in underground coal mines. Research and investigation by Bureau personnel, supplemented by the published results of similar work by European mining authorities, led to the establishment of standards or "schedules." which guide manufacturers ill the design of many types of electrically operated machines and devices used in underground coal Mining. By issuing these standards, Bureau personnel establish the requirements to be met by such equipment before it tan be approved by the Bureau of Mines as permissible for use in gassy coal mines. Every 2 years the Bureau of Mines publishes a list of equipment that leas been accepted as approved or permissible during the preceding 2 calendar years. This is done to inform the mining industry of the availability y of the latest equip¬ment for safe use underground.

Jan 1, 1964

By S. Sakurai

We discuss the mechanical characteristics of underground structures that are subjected to vertical oscillations. Under such circumstances - expected when an earthquake rupture occurs very close to highly developed urban areas - the conventional seismic analysis, which mainly considers horizontal shear oscillations, may not be fully valid. Our analysis, based on the elastic wave theory, shows the effects of vertical disturbances and the generation mechanism of the unique damage patterns observed on the occasion of the 1995 Hyogo-ken Nanbu (Kobe) Earthquake. Wir diskutieren über die mechanischen Eigenschaften der unterirdischen Strukturen, die sich vertikalen Schwingungen aussetzen. Unter solchen Umständen - erwartet, wann ein Erdbebenabbruch sehr nah an hochentwickelten städtischen Bereichen geschieht - kann die herkömmliche seismische Analyse, die sich hauptsächlich horizontale Schubbewegungen überlegt, möglicherweise nicht völlig gültig sein. Unsere Analyse, basiert auf der elastischen Wellentheorie, zeigt die Effekte der vertikalen Bewegungen und den Erzeugungsmechanismus der einzigartigen Beschädigungsmuster, die anläßlich des 1995 Kobe Erdbebens beobachtet wurden. Nous discutons les caractéristiques mécaniques des structures souterraines qui s’exposent aux oscillations verticales. Dans ces conditions - s’attendent quand une rupture de tremblement de terre se produit tout près des secteurs urbains fortement développés - l’analyse séismique conventionnelle, qui considère principalement des oscillations horizontales de cisaillement, peut ne pas être entièrement efficace. Notre analyse, qui est basée sur la théorie des vagues élastiques, montre les effets des mouvements verticaux et le mécanisme de génération des modèles uniques de dommages, que nous avons observés à l’occasion du tremblement de terre 1995 de Kobe.

Jan 1, 2003

By A. Ramage

Since late 2010, CH2M HILL has been working with a confidential client who holds a long-term commitment to sustainable development (SD). The commitment is aligned with all three elements of the triple bottom line: people and society, ecosystems and environment, and financial and economic systems. These commitments are carried forward by the firm?s executives, managers, and operational sites, and are evident in materials posted on the company?s public website. These materials include a formal sustainability report prepared in accordance with the Global Reporting Initiative (GRI) guidelines (GRI, 2006), a report that outlines key SD challenges and progress toward the GRI targets, and a delineation of risks and opportunities outlined in the firm?s Form 10-K and Annual Report. In keeping with its commitments to SD targets, our client wished to consider SD issues in its decision processes for facility expansion or new projects. The company engaged CH2M HILL to meet this goal, based on working relationships established through existing contracts and CH2M HILL?s leading capabilities in sustainable solutions.

Jan 1, 2012

By E. A. Holbrook

The data in this bulletin were obtained during an investigation of screening practice by the University of Illinois engineering experiment station and the United States Bureau of Mines under a cooperative agreement between them and the State of Illinois Geological Survey Division. Earlier work on this subject includes a study of the general practice of coal preparation in Illinois, made in 1914 and published in 1916,1 and an investigation of Illinois coal-washing methods, results of which were published in 1912 in a bulletin 2 that contained complete information on the methods then in use for sizing washed coal. OBJECTS OF THE INVESTIGATION The present investigation was limited to a study of screening as applied in preparing mineral products with the expectation of obtaining more comprehensive information on screening machinery.

Jan 1, 1925

By N Merry, T Cocks

The mineral exploration industry is increasingly aware of the importance of the relationship between mineralogical data and geochemical assay results. However, until recently, the cost and time constraints of most techniques for analysing alteration mineralogy have precluded detailed alteration studies. These impediments have been reduced by the development of the Portable Infrared Mineral Analyser (PIMA), a field portable infrared spectrometer that allows rapid (in field) and cost effective analysis of alteration minerals including subtle variations in mineral crystallinity and composition.   A major application of this technology is in mapping mineralogical variations within hydrothermal alteration systems. Using actual case study examples this paper introduces two approaches to using the PIMA data: 1. for directly mapping alteration systems and using the PIMA data to provide vectors to mineralisation, and 2. for establishing empirical relationships between geochemical data and PIMA spectral data. These applications demonstrate that this technology can be an invaluable tool for targeting and mapping alteration and mineralisation.

Jan 1, 1995

By J. P. McCullough

In 1943, the Federal Bureau of Mines began a program of thermodynamic investigations of petroleum constituents and related compounds. These systematic, long-range studies, which were conducted in the thermodynamics laboratory of the Bartlesville Petroleum Research Center and are still continuing, have resulted in a substantial quantity of data valuable to the petroleum industry and science in general. As separate phases of these studies were completed, the findings were promptly reported in the scientific press. During the past 16 years, 89 journal articles, giving the results obtained for individual compounds and small groups of related compounds, were published, mainly in the Journal of the American Chemical Society and the Journal of Physical Chemistry. In addition, members of the Bureau staff have contributed six chapters to specialized reference books. This circular, prepared in response to many requests, lists these 95 published papers, giving an abstract of the contents of each, as well as titles, authors, and literature citations. The journal articles are listed in the order of their preparation, which closely approximates the chronological order of their publication; hence, the item number to the left of each citation corresponds to the assigned contribution number. For the convenience of the reader, the abstract section is followed by a condensed bibliography, arranged alphabetically by senior author and keyed to the abstracts by appropriate contribution numbers in parentheses after the entry.

Jan 1, 1961

Development of aggregate resources for use in structural concrete has been encouraged in Japan to support infrastructure improvement and national land conservation. Natural aggregate is a valuable resource necessary for sound economic development, and its importance is growing. After completion of aggregate mining projects, planting and afforestation are implemented. But sandy soil in excavation sites is not optimum for the growth of vegetation, and many years are needed before forests are restored. Planting techniques should be improved to support efficient reforestation in a shorter period of time. For this purpose, problems hampering growth of vegetation must to be solved through application of physical and physicochemical techniques to ensure that the environment and the ecosystem will be conserved in project sites.

Dec 6, 2010

By L. P. Weber

During the years 1983-1987, a research programme, jointly performed by the steel producers ARBED, British Steel Corporation, Peine-Salzgitter, Unimetal, and co-sponsored by the European Community for Steel and Coal (ECSC), has been carried out on steel H-piles of different shapes. The initial aim of the testing programme has been the improvement of bearing capacity, both in sandy and clayey soils. At two test sites, standard H-beams are compared to H-piles with different types of laggings or to H-piles grouted both under low and high pressure. In this paper and in view of the open european market in 1992, the H-pile capacities and their corresponding allowable loads, determined from codes, recommendations and computation procedures in use in Belgium/Luxembourg (B/L), France (F), Federal Republic of Germany (G), and the United Kingdom (UK) as well as their evaluation from dynamic CAPWAP and Case methods are compared to the static capacities measured in-situ. In addition, procedures for estimating the load/movement behaviour of H-piles from CPT, pressuremeter, and CAPWAP are compared to the measured curves.

Jan 1, 1991