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By L. H. Harrison

In coal mines equipped with electrically driven mechanical mining equipment, the problem of protection for electrical circuits and machinery important, because the hazards of fires and explosions resulting from electrical failures is greater than in most other industries. There is need for better methods and improved protective devices for this service. Studies and tests designed to determine possible value of the short-circuiting contactor as an electrical device for coal mine service were investigated. Preliminary made to determine the operating characteristics of the device, after which tests were made under actual service in three coal mines. Ordinarily, electrical protection in coal mines is divided into three classes, as follows: 1. Overload protection that is intended to protect against damage from overheating and excessive mechanical strain due to overloading. 2. Short-circuit protection that provides a means of de-energizing the equipment instantly when an accidental short circuit occurs in the equipment or on the power system. Short cm protection tends to damage from fires and, explosions resulting in the dissipation of large amounts of electrical energy in a short circuit. 3. Ground fault protection that, in its various forms, is intended, to maintain the frames of electrical equipment at or near the same potential surfaces in contact with the earth for the purpose of safe-guarding human life.

Jan 1, 1951

On April 5, the potlines at Consolidated Aluminum Corp.'s 35,000 ton-per-year primary aluminum smelter at Lake Charles, La., were frozen when natural gas lines were accidently cut by a dredge. Full production is expected to resume in 3 to 4 months. Three primary aluminum producers announced plans to restore much of the idled capacity in the Pacific Northwest as a result of a special power allocation by the Bonneville Power Administration. Reynolds Metals Co. planned to bring a total of 40,800 tons per year of capacity back onstream at Troutdale, Oreg., and Longview, Wash. The Aluminum Company of America (Alcoa) will restart half of a 23,500 ton-per-year potline at Vancouver, Wash. Kaiser Aluminum & Chemical Corp. planned to restart a 27,500 ton-per-year potline at Mead, Wash., and to bring an additional 10,000 to 20,000 tons per year back onstream at Mead and Tacoma, Wash.

Jan 1, 1980

By K. C. Dean

During the course of the investigation of manganese mineral occurrences in the western United States, the Bureau of Mines collected several lots of ore' from properties in the vicinity of Winkelman, Ariz. As none of the ores would be marketable directly, an investigation was made to determine their amenability to concentration by ore dressing. The Geronimo group of claims is in Pinal County, 8 miles west of Winkelman, Ariz. The manganese oxides occur as cementing material in ore zones of conglomerate. Representative samples of a 2-ton lot of ore cut from outcrops of two lenticular deposits were laboratory-tested. Two 1-ton samples from the Benningfield property were similar in physical characteristics but differed in grade. This claim is 11-1/2 miles south of Winkelman and about 1 mile west of the San Pedro River on the south side of Putman, Wash. The manganese minerals occurred as nodules and lenses, replacing limestone, in a capping over a dark, igneous dike. The North Star group consists of five claims on the west side of the San Pedro River 14 miles south of Winkelman. The ore consists of a low-grade, manganese oxide-calcite occurrence interspersed with stringers of higher-grade material and is present as filling in a fissure zone in porphyry. Two samples were obtained by the examining engineer; one sample represented run-of-mine material, the other represented ore from the vein that could be hand-sorted or selectively mined.

Jan 1, 1952

By Karl J. C. Harries

"5.1. INTRODUCTIONThis chapter is intended as a general overview of the subject of royalties between private parties – royalties extracted by governments are not dealt with. This same subject is covered in detail in Volume II, which critiques many sample provisions taken from agreements, giving both pros and cons. If you find something that interests you in this chapter, check Volume II for extra information. Detailed cross-referencing to Volume II has not been attempted, however, most subjects mentioned in this Chapter will also appear in Volume II, usually in greater detail. Reference should be made to the Index.A Brief History of Royalties1In the early days of mining in Canada, the tendency was to sell a claim for cash and to move on, using the stake to look for and stake more prospects. As prospectors became more sophisticated and Canada’s North opened up, the market for properties and the number of mining properties available increased dramatically. Speculation and the practice of consolidating several small properties into one large holding entity became common. In “hot” areas, the speculators2 could far outnumber the prospectors, many of the former having little or no prospecting expertise but lots of market and promotional savvy. However, to consolidate a number of small parcels into one large project can be expensive, and many of the parcel owners became interested in keeping a share in the project, rather than giving up everything. Speculators who were trying to consolidate small parcels wanted to minimize cash payments to parcel holders (usually they did not have much cash and preferred it flowing in their direction rather than away from them). Accordingly, non-cash transactions were developed to meet the aspirations of both owners and speculators."

Jan 1, 2003

By Boyd Guthrie

As the American petroleum industry surveyed its position in early 1937, it had many reasons to be optimistic concerning its future. The industry had emerged successfully from the depression, and for the first time since 1929 it had produced over one billion barrels of crude oil in a single year. The demand for gasoline and fuel oils was up, and reserves of crude petroleum and production capacity seemed adequate for the future. Although production of crude oil dropped slightly in 1938, the oil industry was still in a good position with respect to its supply of raw material, which improved economically in 1939 with the decrease of crude-oil stocks in storage above ground. However, by 1940 a threatening cloud (the invasion of France and its rapid surrender) had appeared on the horizon. This aroused Somme fears as to the industry's immediate future, and these fears were intensified the following year when the United States entered World War II. As the war progressed, more and more ships, planes, and vehicles were produced, and the problem of obtaining enough liquid fuels to supply them intensified. Hearings were held in August 1943 before a subcommittee of the Committee on Public Lands and Surveys of the 78th Congress to determine the advisability of passing legislation to promote the development of synthetic liquid fuels.

Jan 1, 1951

The scope of this paper is to introduce a mathematical model based on matrix algebra in order to determine similitude quantities, which can be arranged in specific formats to simulate the field conditions and associated behaviour. The formulation of a typical mathematical model applicable to Geomechanics is demonstrated here. The examples provided are intended to facilitate comprehension and application of the proposed model in practice.

Jan 1, 1989

Arsenic.--Inorganic arsenic has been added to the Environmental Protection Agency's list of hazardous air pollutants because of a high probability it can cause cancer. EPA estimates that inorganic arsenic emissions into ambient air total more than 6,000 tons per year, with about 65;L of this coming from the operations of copper, lead, and zinc smelters. Asbestos Detection.--In June 14, the President signed S. 1658 providing $172.5 million to detect and remove asbestos hazards in schools. Asbestos Use Must be Reported.--All firms using asbestos in the manufacture of some 30 categories of products must describe in detail how they use the mineral to the Consumer Product Safety Commission, for all manufactures since January 1, 1977.

Jan 1, 1980

By C. T. Baroch

The purpose of this report is to describe the design features and techniques used in operating a plant capable of producing about 1,500 pounds of titanium metal per day. The process used was based on the reduction of titanium tetrachloride with magnesium, a modification of what is generally known and spoken of as the Kroll process. Sponge metal crushed to melter's specifications was the end product of the operation as conducted. The report is divided into sections covering general plant layout and the major unit operations. These, in turn, are each divided into discussions of the equipment, operating procedures, and typical results. Descriptions are given in more detail than is generally expected of a technical report. During 1953 and 1954 over 130 engineers and businessmen, officially representing some 80 industrial, chemical, end engineering firms, visited the operating plant, and their questions, which indicated a serious interest in details, have served as a guide for the material contained in this report.

Jan 1, 1955

By R. G. Zaripova, N. D. Ryan, H. J. McQueen

The austenitic and ferritic stainless steels do not undergo any phase transformation that induces very fine grains in the product through thermomechanical processing as practiced in most other steels. Considerable grain refinement can be achieved by intense multistage deformation descending through warm to cold working; notably multi-axial forging of bulk material can attain high strains with diminished risk of cracking. Hot working to improve ductility yields finer grain sizes as the T is reduced and strain rate E raised; increased strain has limited effect due to the steady state regime. Ferritic steels develop subgrains with size diminishing as E rises and T falls with the advantage of retained strain hardening; recrystallization delivers grains several times the cell size. In austenitic steels, dynamic recrystallization (DRX) provides finer grains at higher E and lower T with a lower limit due to intergranular cracking. The DRX grains contain a strengthening substructure that can easily be retained by quenching; if static recrystallization is allowed to occur the grain size rises markedly. Multistage rolling with diminishing T is able to provide grain refinement to the same degree as straining at the finishing T yet provides better ductility. grains on recrystallization. As a result of the strain induced transformation to martensite, small subzero deformations of austenitic or duplex steels produce very high dislocation densities that yield marked grain refinement when they revert upon reheating.

Jan 1, 2004

By Paul Sarnoff

The economics of precious metals -- depending upon who is involved --could be the economics of hope, of fear, indeed of profit and perhaps survival. For those investors seeking capital gains in a puzzling economy, precious metals involve the economics of hope. Those who are convinced that currency soon won't be worth the paper it's printed on turn to precious metals because of the economics of fear. Gold and silver have been a storehouse of wealth since biblical times. The economics of fear during the past 500 years on the Continent has caused almost every European family to make sure a private stockpile or hoard of gold, silver or coins is at hand in case the paper currency of their country undergoes the kind of disaster that came to the German Mark after World War I. Understandably, for mining companies involved in the production of precious metals, the elements of operations and management are directly concerned with the economics of profit -- and perhaps survival. To the American miner the price of precious metals in the marketplace is a matter of daily concern. After decades of selling silver to the US Government at 64.64 cents an ounce, producing silver mines suddenly became faced with prices breaking $5, $10 and $20 per ounce, and approaching $50 an ounce during the period 1978-1981. What should the miner expect one year in the future? Five years?

Jan 1, 1981

By S Winter, G Klenowski

During longwall mining in the Bowen Basin, open tension cracks formed by overburden subsidence occur to a height of about 175 m above the mining horizon. Within this zone, water in aquifers or inundated workings will flow into the mine.At the Oaky Creek mines Aquila seam, open cut pits containing pit water overlie German Creek seam longwall panels at a height of about 105 m. The highly saline water is classified as contaminated and cannot be discharged off-site. Because alternative water storage facilities were not available, innovative water management solutions were needed to allow longwall mining to proceed without underground flooding.Computer modelling and underground inflow measurements have been completed to accurately determine inflow rates into longwall mines from overlying water sources at increasing overburden heights. Research work has also included determining cost-effective blanket treatment of final voids and reshaping spoil piles to minimise downward seepage.Ponded water overlying the Aquila low, Grasstree south and A6 pits required remedial works prior to longwall undermining to prevent flooding. In the Aquila low pit it was necessary to partition the pit and remove water overlying longwall 32. Two in-pit bridges were constructed by dozing and track compacting low wall spoil. The final void above the longwall panel was kept dry during undermining. Maximum recorded underground inflow rate was 30.0 L/s.The Grasstree south pit final void, part of the ramp and much of the spoil piles were inundated prior to undermining of 308 panel. A bridge and blanket were required to prevent ponding above the longwall. Maximum recorded inflow during undermining was 23.2 L/s.The pit A6 south final void, which contained dumped, saturated rejects and inundated highwall mining entries was undermined by longwall 36 at the Oaky No 1 underground mine. Because mapping of highwall entries was not available, the maximum calculated inflow rate of 73.0 L/s was based on all design entries being fully inundated. The actual inflow rate during longwall mining ranged up to 20.0 L/s.Water management improvements that have been implemented include greater use of contaminated pit water to wash coal, use of evaporation fans, and installation of a 6 ML/day reverse osmosis plant for water purification.CITATION:Klenowski, G and Winter, S, 2017. Inflows into longwall mines from inundated overlying workings, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 183–190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

The Environmental Session will consist of five papers dealing with various aspects of trace elements associated with coal. Analytical procedures to determine the amounts of trace elements will be discussed. Other papers will deal with trace elements in streams downstream from coal mines, potential pollution from wastes from coal preparation plants, potential recovery of trace elements, and potential pollution from trace elements as a result of the combustion of coal.

Jan 1, 1979

By Karl J. C. Harries

"10.1. INTRODUCTIONDefinitions are a necessary part of every agreement. Their purposes are to assist the reader in reading and understanding an agreement and to attempt to avert potential confusion and, therefore, disputes. In some circumstances, they may be critical in deciding a dispute. As they are often substantive, they should not be treated lightly.It is far easier and less confusing for a reader to read “the Company” or “the Recipient” than to be faced with “the party of the First Part”, or to see the “Jones Property” than “that part of the property hereinbefore described in paragraph 1.01 hereof”. It is also advisable not to use “-ee” and “- or”, as in payee and payor.One thing must always be remembered: once a word has been defined in an agreement, it will always have the defined meaning unless the contrary is clearly indicated or is required to make sense of a provision.2 It can be confusing for a reader if commonly used words are defined in other than ordinary terms. Unique words that will stand out in the text are more likely to be recognized as having special meaning. It is also good practice to identify defined terms by capitalizing them in the text of the agreement. Boldfacing of definitions is also sometimes used for this purpose but, as boldfacing is not easily identified in handwritten revisions, it can be missed in the press of negotiations, especially when several typists are involved. Lack of consistency in identifying defined terms is not a fatal mistake, but it can create confusion, especially if the reader is new to the agreement or is reading it in a highly technical manner, such as when there is a dispute.If definitions used in the main text also apply to a schedule, they need not be included in both. Omitting them from the schedule makes the agreement look shorter, which to some people is a benefit. If definitions are not repeated, make certain that the schedule clearly indicates that words defined in the main text have the same defined meanings in the schedule3 and are clearly identified as defined words. In considering whether or not to repeat in a royalty schedule definitions appearing in the agreement proper, think of definitions as an aid and a reminder to the reader. Repeating them will help a reader, if only by saving the nuisance of remembering where to find them in the main text and constantly turning to it. All the definitions needed to read the schedule will be right there, so that the schedule is a self-contained document. Just make certain that, if you do repeat a definition, you repeat it in identical terms. If you have to change any defined term to make it fit the royalty provisions, use a different word or phrase as the defined term to warn the reader that he is dealing with a different concept.4"

Jan 1, 2003

By W. E. Foreman

A mathematical model was developed to assess the costs for reclamation of surface mining using the shovel overcasting operation, the front end loader operation, and a backfilling operation. A literature review was made of the present laws in Kentucky, Pennsylvania, Virginia, and West Virginia pertaining to surface mining and of the various parameters that influence the input data for a mathematical model. It was determined that the working mathematical model would have to be applied on an area to area basis, preferably on a permit by permit basis in the area where surface mining was being done. To this end, a flexible model was developed with input data obtained from the area of study. The results of the study show that the cost per ton of coal for reclamation can be estimated for various reclamation levels. Validation of the model was done for selected permits from Virginia. It was determined that the permits could easily be used for input data to the model.

Jan 1, 1974

By G. T. Austin

This is an overview of the gemstone industry with special attention on particular states within the united states. The U.S. Bureau of Mines, Department of the Interior compiled and analyzed the information contained in this report. The report should be viewed as a current "still photograph" of a dynamic system. The information presented on a specific gemstone or for a specific state can and will change with time. This overview presents historical and reference information on the principal gemstones and their production in certain states. The report is not a definitive work on gemstones within the select states or United states.

Jan 1, 1995

By Steinar L. Ellefmo, Thomas Kuhn

The deep-sea ocean floor offers a great potential for mineral resources. The evaluation of these resources is both time consuming and costly and require as any resource evaluation data; geodata. The collection of hard data, physical samples, is of course preferred because the associated uncertainty is low. However, the collection of soft data or image derived data can offer a valuable supplement. In this paper image derived nodule uncertain abundance data from an area in the Pacific is utilized. Implementing these uncertain data improves the estimation when the quality of the estimation is measured using the classification indicators like the kriging standard deviation, the relative prediction error, the slope of regression and the weight of the mean. It is concluded that uncertain data is better than no data. INTRODUCTION The deep-sea offers vast mineral resources (Cathles (2011), Hannington et al. (2011), Hannington (2013), Singer (2014)). A mineral resource can according to increasing geological confidence be classified as an inferred, an indicated or a measured resource. The classification is performed by a competent- or qualified person and is dependent on the amount, quality and characteristic of available geodata. The competent person must have at least five years of experience relevant to both the style of mineralisation, the type of deposit and the performed task. Typical examples of a “task” is for example resource estimation and classification or planning- and execution of exploration activities and presentations of the results. The competent person must also be a member or a fellow of a professional organisation and thereby be bound by reporting code (-s) that defines minimum standards, recommendations and guidelines for public reporting.

Jan 1, 2018

By Enrique Monge Gordillo

Si bien el fierro es el metal más barato en la industria minera, el incremento de su demanda y agotamiento gradual de sus depósitos, genera que su costo se eleve progresivamente. Por tal motivo, el objeto del presente texto describe el proceso de consumo del hierro y acero y su repercusión en el mercado occidental a través de cuatro capítulos: El primero, refiere a la demanda de hierro y acero tanto en Estados Unidos, los depósitos en Québec y Labrado en Canadá, el tratamiento y comercio de minerales de hierro; el segundo, a las operaciones mineras en Canadá y América Latina como las de Canadá, Venezuel, Brasil, Chile, Perú, México, Colombia, Cuba, Santo Domingo, Argentina, entre otros países; el tercero, revisa las plantas de hierro y acero en América Latina como las de Brasil, México, Chile, Argentina, Colombia y Perú, mientras que el último, refiere la industria de fierro y acero en los Estados Unidos, producción de fierro cochino y costos e importaciones del acero.

Jul 20, 1959

By Hamid Maleki

A comprehensive study consisting of stress determinations, core logging, laboratory testing, and numerical analyses was conducted to investigate the cause and potential alternatives to the coal bump conditions that developed in the Second North Panel of the Little Dove mine near Buntington, Utah. Roof rock characteristics were such that a cave did not develop above this 420 ft wide panel. After 700 ft of pillar retreat, severe coal bump conditions developed during pillar mining. The coal bump conditions resulted from excessive pillar stress which was caused by load transfer from the extracted, noncaving, portion of the panel. Site specific data and numerical modeling techniques were used to back-analyze the bump prone condition. This back- analysis lead to the identification of critical stress, closure, and energy release levels. These critical levels were then used to evaluate alternative pillar mining sequences in the hope that the potential for coal bumps could be reduced. It was found that while alternative sequences offered some potential improvement over the pillar mining sequence used in the mine, alternative pillar mining sequences would not significantly reduce the potential for bumps. For the roof characteristics at this mine, coal bumps are best avoided by developing narrow panels or significantly wider panels, which incorporate properly sized barrier pillars. Narrow panels, on the order of 300 ft, would not cave, but panel pillar stresses and the potential for umps would be moderated by the reduced r' panel width. Wider panels, of approximately 650 ft, would allow a cave to develop, also reducing panel pillar stresses and coal bump potential.

Jan 1, 1987

By R. W. Raymond

EDWARD COOPER, was born in New York City, October 26, 1824. His father, Peter Cooper, to say nothing of manifold reasons for fame as an inventor and philanthropist, deserves to be remembered as a pioneer in the establishment of public schools; and it is not surprising that he sent his son to one of the democratic institutions in which he was himself so ardently interested. From the public school Edward Cooper went to Columbia. College, where he made the acquaintance of Abram S. Hewitt, who was first his tutor, afterwards his traveling companion, brother-in-law, business partner and life-long friend.* For twenty years I was the consulting engineer of the firm of Cooper & Hewitt, and also connected with the work of the Cooper Union, in which they were both deeply interested and faithfully active. On the basis of the intimate knowledge thus gained, I venture an estimate of Edward Cooper's character and career which, if not fully comprehensive, may facilitate a juster estimate than would be reached by the strident of those data which the modesty of the man permitted to be placed upon public record. Edward Cooper's mind was one of the most active, accurate and subtle with which I have ever come into contact: He had inherited from his father a sunny, benevolent temperament, and' the irresistible impulse to attack all new problems which challenged his attention. His thorough education had 'indeed made him wiser than his father, both in philanthropy and in technical inventions. He could condemn and reject a proposition which Peter Cooper would have embraced, in a splendid, though ignorant, faith that nothing was impossible to an. American, and that the word ? impossible " was simply a label,

Jul 1, 1906

By Ryan C. Linthicum

A system of steel sheeting and multiple levels of high capacity double corrosion protected soil anchors were used to restrain a major slope failure that occurred at the base of the Watchung Mountains mid-way through construction of a 650,000 SF retail center along Route 22 in Watchung, New Jersey. The implementation of a design-build earth retaining structure was necessary to stabilize and repair the disturbed mountainside in a timely fashion to permit completion of the retail center on a fast track schedule. The tied back steel sheetpile wall was approximately 2,000 feet long and varied in height from 12 to 25 feet. The hillside extended approximately 350 feet above and 600 feet beyond the wall with the main failure scarp extending 50 feet above and 90 feet beyond. The wall was constructed in a top-down manner and required the installation of 475 anchors to resist loads of up to 70 kips/ft produced by the creeping hillside and groundwater flows from both a series of springs and steady state seepage through an inclined zone of fine sand. Incorporation of a unique tie point connection eliminated the need for a waler, facilitating and simplifying modifications to anchor locations based on anchor load test results and conditions encountered during construction. Post grouting also proved to be an essential element in the successful construction. This paper presents the design and the construction methods used to restrain the significant earth lateral loads produced by a slope failure using steel sheeting tied back with high capacity soil anchors with anchor loads distributed to the sheeting through a unique tie point connection on a fast track schedule. Installation techniques, testing programs, and construction quality control are also discussed.

Jan 1, 2003