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By Philip C. Tully

These modifications to the Redlich-Kwong equations for pure hydrogen and neon were developed after an unsuccessful attempt to generalize a modification technique previously developed for helium. New coefficients of the B terms were developed by minimizing the residuals. No changes were made in the coefficients of the A terms. For normal hydrogen, B was changed to [0.08063Tc PcT] for temperatures from 980 to 423° K and pressures up to 1,050 atm. The average deviation in Z was 0.36 percent with maximum deviations less than 1 percent for all but a few low-temperature points. For neon, B was changed to [PCT 0.1025T], for temperatures from 120° to 973° K and pressures up to 1,500 atm. The average deviation in Z was 0.34 percent with maximum deviations less than 1 percent for all but a few high-pressure and low-temperature points. Efforts to attain a lower temperature range to comparable accuracy with this type of modification were unsuccessful. In the range of applicability, these equations should be used with caution when calculating derived thermodynamic functions, such as the isobaric specific heat.

Jan 1, 1968

By James Gibbs

In order to provide an initial approach to the deposits of oil shale, nahcolite, and dawsonite in the central area of the Piceance Creek Basin in northwestern Colorado, the U.S.B.M. and associated contractor personnel drilled and cased a 96-inch ID shaft to a depth of 2,371 feet. The shaft was constructed using "big hole" drilling techniques and succeeded in giving access to previously inaccessible deposits of the above minerals. This report documents the construction from its beginning in January 1977 to its completion in January 1978. Procedures used and problems encountered are discussed in derail.

Jan 1, 1978

By Loren R. Anderson

A probabilistic slope stability computer model was developed at Utah State University and independently evaluated by CH2M Hill Consulting Engineers as a design and analysis tool. Volume I of this report describes the model and Volumes III and IV are users manuals for the computer programs. This volume (Volume II) constitutes the report by the CH2M Hill. It includes a description of a field investigation and stability analysis of an existing tailings dam. Based on the results of the analysis, the tailings dam was evaluated for redesign using probabilistic considerations. Conclusions are made regarding the usefulness of the model as a design tool.

Jan 1, 1982

By L. D. Schmidt, Wm. Seymour, W. S. Landers

"INTRODUCTION The relative value of the various individual physical and chemical properties of coke as a measure of its performance in the blast furnace as aroused considerable controversy but it is generally agreed that uniformity in these properties is extremely important if maximum mum pip-iron production is to be attained. The control of,the bulk density or weight per cubic feet of the coal charge in the coke ovens is a major, and frequently overlooked, factor in producing a uniform product and in efficient operation of the coke plant.This report presents a brief discussion of the general problem of bulk-density control and the results of tests on samples of coke-oven charges from several operating plants experiencing difficulties due to lack of adequate control. These tests covered the effect of moisture and oil content on the bulk density of the coal. Some tests on the effect of a wetting agent and furnenous of gained were also made. A description of the methods used to determine the bulk density of the coals studied in this investigation and of the methods used to apply oil to the coal at byproduct-coke plants are included in this product. No theoretical analysis of the data presented in this report, because the primary purpose of the investigation was to obtain data of immediate practical value to the plants concerned."

Apr 1, 1945

By C. Richard Groves

As the level of technology applied in the electrical measurement, control, and display portions of mine hoist systems continues to advance, the issues and concerns associated with the ramifications of the application of microprocessor technology on the safety-related aspects of these systems become paramount. This report, in part tutorial, addresses several aspects of these concerns. Beginning with discussions of microprocessor-based system architectures, the report addresses some existing and anticipated uses of this technology in mine hoist systems and discusses safety related considerations associated with the areas of data derivation; control and display panels; and system reliability issues. The report concludes with electrical maintenance and inspection considerations associated with the safety assurance of microprocessor based mine hoist systems.

Jan 1, 1986

By Dale William Avery

Thirty mines and prospects were studied; 22 are within the Dolus Lakes RARE II area. Three properties within the area and one adjacent to it were determined to have indicated or inferred gold, silver, or molybdenum resources (fig. 1 and table 1) associated with quartz veins and shear zones or quartz-pyrite stockworks in granodiorite. Five other properties in the area and three just outside have potential for the discovery of gold and silver resources. Minor amounts of very fine-grained placer gold are in glacial outwash in and near the area. The John G. Carlisle Mine (fig. 1, no. 9) produced 120 oz (3.7 kg) of gold between 1897-1899. The Independence Mine produced 481 oz (15 kg) gold, 197 oz (6.1 kg) silver, and 189 lb (86 kg) of copper between 1926 and 1935. These mines are adjacent to the study area's northern boundary.

Jan 1, 1983

As a result of early experiments in underground mine illumination, the Bureau of Hines recognized the need for additional experience with the underground lighting of coal mines having low seam thicknesses. There was already experience with tile illumination of coal mines having higher coal seams, and this contract with Ocean Energy Inc. (OEI) was undertaken to contribute to the "low coal" experience. For the purpose of this contract, a "low coal? mine is defined as one having less than 45 inches of overall headroom in the working places. As a practical limit, 26 inches was the minimum coal seam thickness to be encountered in this program. In one instance, the maximum coal seam thickness was eight to ten feet, however, this particular work was at the direction of the Technical Project Officer (TPO) by virtue of the unique type of lighting arrangement that was to be evaluated which would be useful for low coal. At the outset of the contract, three major tasks were established. The first two tasks involved the installation of permissible fluorescent lighting equipment at two low coal mines. The intention was to illuminate mining sections in each case consisting of one or more machines. The third task was to illuminate a variety or mining equipment including a longwall. For the purpose of this report, the fol-owing identifies the particular installations associated with each task.

Jan 1, 1976

By M. J. Ankeny

All bituminous-coal mines, by the nature of their product and inherent gassy tendencies, are subject to explosions or mine fires. The evolution from large, hand-loading sections employing numerous men and containing open-type equipment, lights, and nonpermissible explosives to small, concentrated mechanical sections with but few well-supervised men utilizing modern preventive equipment has not altered this premise. Mine catastrophes such as Centralia and New Orient No. 2, as well as recent disasters of less magnitude, have refuted the trend of thinking that modern equipment, will prevent or localize explosions and prevent widespread or loss of life.

Jan 1, 1952

By Thomas P. Dolley

Building stone, cassiterite, kaolin, gold, lime, and peat were the only commodities mined, The country's main economy was in agriculture, primarily in coffee exports. Tribal violence occurred again, between the Hutu and Tutsi tribes, causing an estimated 50,000 deaths, mainly in rural and mining areas. The inflation and a large deficit continued. The country continued to import cement, fertilizers, oil, and petroleum products. Burundi possessed numerous small gold deposits. The northwest and north-east were the country's two most important gold-bearing regions. A large kaolin deposit was found at Ngozi, and its mining was specified in the fifth 5-year development plan for 1988-1992. In the area of Rugombo, limestone was being explored with the intention of opening a cement plant.

Jan 1, 1990

By H. M. Cooper, R. F. Abernethy

Determination of the fusibility of coal ash consists in melting a pyramid of the ash to fluid under prescribed conditions . The conditions of the test are specified by the American Society for Testing Materials4/ and must be adhered to strictly if comparable results are to be obtained . The Society formerly specified a particular type of furnace , but with improvements in design of both electric and gas furnaces , it was decided by the Society to specify only essential details of the test . The Chairman of Committee D - 5 , Coal and Coke , of the American Society for Testing Materials suggested that the Coal Analysis Section of the Bureau of Mines conduct a cooperative investigation on the effect of furnace type and atmosphere upon fusibility of coal ash . The Coal Analysis Section enlisted the aid of a number of laboratories using the more common furnaces to cooperate in the investigation . Four types of gas furnaces burning natural and manufactured gases and two types of electric furnaces with different methods of maintaining a reducing atmosphere were employed . The results from the survey are tabulated herein , and some comparisons are made . There were not enough data from any particular furnace and atmosphere to make a reliable statistical analysis . However , definite tendencies are evident , and attention is called to them by direct comparison. in tables .

Oct 1, 1943

By M. P. Board, J. K. Whyatt, T. J. Williams

The U.S. Bureau of Mines has been conducting a series of rock mechanics investigations at the Lucky Friday Mime in the Coeur d'Alene Mining District of northern Idaho. In the present study, the energy release rate (ERR) index was used to evaluate three underhand stope backfill parameters--cement content, density, and placement gap-to determine their influence on rock bursts. This index provides a relative measure of the likelihood of rock bursting for a given rock mass. It is known that the elastic idealization of the rock mass inherent in this method causes underestimation of stope closure and hence underestimation of the influence of backfill on rock bursting. However, this evaluation still showed that (1) changing from present practice to one in which backfill was omitted altogether would increase the ERR by 42 pct and (2) perfect placement of backfill would reduce the ERR below present practice levels by 28 pct. The easiest step toward perfect placement would be elimination of the placement gap, which accounted for half of the difference in ERR between present practice and ideal placement conditions. There was no indication that increasing initial fill strength through increased cement content would affect the ERR.

Jan 1, 1992

By Sarkis G. Ampian

Published optical microscopic and X- ray diffraction characteristics of the following compounds are critically evaluated and compared with Bureau of Mines data : Tricalcium aluminate , calcium monoa luminate , dodecacalcium heptaluminate , dicalcium silicate , tricalcium silicate , and sodium aluminate . A recommended set of definitive optical and X- ray diffraction characteristics is presented . These values are used to identify products of the lime soda sinter process for production of alumina . Polymorphism of gamma- , beta- , and alpha prime - dicalcium silicate is reexamined , and new data are presented on polymorphism of tricalcium silicate and sodium aluminate by high- temperature X- ray diffractometry . Polymorphism is not observed for tricalcium aluminate , calcium monoaluminate , and dodecacalcium heptaluminate . Bureau of Mines data indicating a stoichiometry of 12Ca0.7A10 for the phase 5Ca0.3A1 0₂ are discussed . A critical review of the literature concerning calcium dia luminate and sodium undecaluminate ( 8 -A10 ) is also included .

Jan 1, 1964

By Eric Nordhausen

This report and associated deliverables is the culmination of a comprehensive literature survey, data collection and identification of over 500 metal/nonmetal active mines/mills/smelters (over 50,000 tons per year, TPY, production) in the contiguous 48 states. The main purpose was to compile an inventory of the mine/ mill/smelter waste tonnages, thus forming a data base for future research and development in improving waste management and waste disposal techniques in the metal/nonmetal mining industry. The study specifically excluded sand and gravel, sulfur, granite and any commodity that leaves basically no waste when mined and/or milled. The coal waste inventory is the subject of another report. The study provided for locating, mapping. encodating and digitizing all the mine/mill/smelter information made available throughout the nation as well as the climatological, land use, topographical, ecological and vegetative data. Mine/mill/smelter information also included (where possible) acreage and/or volume, mining methods, primary ore and gangue minerals, waste composition and haulage methods and distance hauled. Finally, a discussion is provided concerning present and potential uses of various types of tailings, as well 8S recommending possible R&D in addressing problem areas in waste disposal techniques and management.

Jan 1, 1981

By William Porter

Hand scaling is a physically demanding job and is responsible for numerous overexertion injuries in mining. This experiment studied rib scaling from an elevated bucket to examine force generation capabilities and electromyographic responses to a prying subtask. Subjects exerted force using two bars (steel and fiberglass) at five target heights. Work height significantly affected peak prying force during scaling activities with highest force capacity at the lowest level (p = 0.0188). Bar type did not affect force generation (p = 0.7843): However, use of the fiberglass bar required significantly more muscle activity to achieve the same force (p < 0.05). It was concluded that miners should scale points on the rock face that are below their knees, and reposition the bucket as often as necessary to do so. Additional research is needed to fully understand the impact of bar type on the physical demands of an entire scaling task.

Jan 1, 2006

By Carl N. Anderson

This paper, which is one of a group presented by the United States Bureau of Mines covering mining practice in different districts, deals in particular with the methods employed in mining the horizontal type of zinc-lead orebodies of the West Baxter area of the Tri-State zinc and lead district. These orebodies, locally termed "sheet-ground" bodies, with their relatively low working faces and low tenor of zinc and lead, require changes in the mining practice which is used in the balance of the district. In addition to the general mining methods, this paper also describes the system of hand sorting employed prior to the direct milling of the ore. The Hartley mine is situated mile west of Baxter Springs, Kans., as indicated in Figure 1. Its general outline and the location of the shafts with respect to the milling plant are shown in Figure 2.

Jan 1, 1932

By Max J. Spendlove

This Bureau of Mines publication reviews current recycling trends in the United States. Although near-term prospects are poor for recycling most present wastes, urban refuse is an important exception. Such wastes comprise a mine above ground, and much less processing energy is normally required to recycle the constituents of urban ore than to obtain them in equal amounts from natural raw materials.

Jan 1, 1976

By E. P. Youngman

The basic mining law of Netherland India is contained in N. I. Statute 1899 , No. 214 , as amended by N. I. Statute 1910 , No. 588 , and 1919 , No. 4 , which is quoted as the " Indian Mining Law, " the effective date of which was fixed as May 8 , 1907 , by proclamation dated October 12 , 1906. The Indian Mining Law was supplemented by Ordinance No. 38 , of 1930 , which was passed by the Volksraad on March 18 , 1930 , to become effective on October 1 , 1930 ( superseding an earlier ordinance entitled " Government Gazette , " 1906 , No. 434) . An important law with respect to American petroleum rights , Statute No. 23 , passed February 9 , 1928 , approving contracts between the Indian Government and the Netherland subsidiary of a large American oil company , is in the nature of a private law or of an enabling act ( see section of this paper entitled " Rights of Foreigners" ) . Statute 1930 , No. 348 , effective October 1 , 1930 , sets forth in minute detail conditions under which prospecting and mining permits may be granted. Statute 1930 , No. 341 , effective October 1 , 1930 , embodies the police regulations of the mining industry.

Jun 1, 1931

The Mine Safety and Health Administration (MSHA) defines an independent contractor as any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine. Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Jan 1, 2008

By William G. Pariseau

The research reported here concerns ground control in multi-seam mining and relates mainly to the analysis of stress about multi-seam room and pillar mines. The two variables of most concern are distance between seams and alignment of pillars between seams. The first year results of the two year investigation apply to the development phase of mining when the extraction is typically less than 50 percent. The second year effort is concentrated on retreat mining and barrier pillar safety when the extraction is typically greater than 50%. The procedures in both cases are readily applicable to more than two seams. Although two seam mines are the most frequent type of multi-seam operations, because of the potential for three seam operations in the Western United States, a number of three seam development analyses are also presented. The results enable one to make a rapid assessment of stability of rooms and pillars during production and barrier pillar size during extraction of adjacent panels. In the event of low safety factors, more site-specific analyses can be undertaken.

Jan 1, 1983

By Lon A. Williams

This appendix contains drawing lists and drawings of components and assemblies designed for the prototype portable and machine mounted lighting systems per Tasks II & IV of Contract No. H0220065.

Jan 1, 1976