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By J. Douglas Causey

A U.S. Bureau of Mines study indicates over 200 million yd3 (153 million m3) of cinder resources occur in the Mount Washington Wilderness. No future demand for the deposits is anticipated. Based upon the geologic environment, the area is considered favorable for discovery of geothermal resources. INTRODUCTION The Mount Washington Wilderness, located about 32 mi (51 km) west of Bend, Oregon, contains 46,655 acres (18,881 ha) (fig. 1). A 6,300-acre (2,550-ha) addition on the northeast and east boundaries has been proposed by the Forest Service under RARE II. The U.S. Geological Survey made regional geological, geophysical, and geochemical surveys, and the U.S. Bureau of Mines examined, analyzed, and evaluated the economic potential of prospects and commercially important mineral resources.

Jan 1, 1982

By R. J. Hundhausen

The Takilma-Waldo copper district in Josephine County, Oreg., was studied by the Bureau of Mines from September 1950 to April 1.951 and from December 1953 to April 1954. Funds for the investigation were provided by the Bureau of Mines and the California-Oregon Power Co., Medford, Oreg., on a cooperative basis. The copper mines in the district are credited with a total production of ore worth $1,700,000. Since 1933 the mines have been unproductive and, except for minor exploration, largely inactive. The history of the district indicates that the copper deposits were mined principally during periods of high metal prices.

Jan 1, 1956

By W. L. Dare

The Federal Bureau of Mines is publishing a series of studies on the methods and costs of mining uranium on the Colorado Plateau. This report describes the longwall-mining methods and techniques used at the Radon mine, Big Indian district, San Juan County, Utah. The tabular Radon ore body lies on the southwest flank of the Lisbon Valley anticline, strikes N. 10° W., dips 7° SW., and has an average thickness of 4-1/2 to 5 ft. The mine is developed by a three-compartment vertical shaft, a haulage level driven beneath the ore, and a system of drifts driven within and parallel to the strike of the ore.

Jan 1, 1961

By E. P. Youngman

The mining law now in force in Finland is the Imperial Russian Ukase of 1883, promulgated November 12, 1883, by Czar Alexander III, with the sanc- tion and permission of the Finnish Estates. This law repealed prior legisla- tion, as follows: Crdinance of liay 25, 1857, concerning the appropriation of ores and minerals; as wall as the right to remove and utilize them; proclama- tion of January 20, 1868, amending, the ordinance of May 25, 1857; proclama- tion of October 3, 1621, concerning the appropriation of precious metals; and the proclamation of October 30, 1878, concerning prospecting for gold, etc., in Finnish Lapland. A proposal for a new mining lar is still being considered by the Finnish Diet. This new law, if and when promulgated, will differ only slightly from the law of 1683 but will be drafted in more modern language."

Jun 1, 1932

By J. A. Herdlick

"INTRODUCTION The Bureau of Mines began a broad program of exploration of various proportion in the Pine Creek area of the Coeur d'Alene mining region in the fall of 1943. As a part of this project, exploring was done at theLittle Pittsburg property in 1945. The work included driving a 500-foot crosscut from the No, 6 level and drilling four diamond core drill holes to test the behavior of the Little Pittsburg vein at depth. This report presents the data obtained by the Bureau.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources, to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyses samples and performs beneficiation tests.The Bureau's exploration of the Little Pittsburg vein was one of the activities of the Albany Division of the Mining Branch, S. H. Lorain, chief. The project was started by R. M. Gammell, mining engineer, and was continued by the author and J. R. Reynolds, assistant mining engineer.The chemical analyses included in this report were made at Reno, Nov., under the direction of A.C, Rice, acting engineer in charge, Rare and Precious Metals Experiment Station, Bureau of Mines.The cooperation and assistance of the management of the Denver Development Co. is gratefully acknowledged, in particular that of C. E. Nugent, who made available much of the operational data included in this report."

Jan 1, 1947

By Clive Ellis, Brian Davies, Steven E. Mischler, Jon C. Volkwein

A primary means to reduce environmental levels of diesel particulate matter (DPM) exposure to miners is to reduce the amount of DPM emission from the engine. A quick and economic method to estimate engine particulate emission levels has been developed. The method relies on the measurement of pressure increase across a ?lter element that is brie?y used to collect a DPM sample directly from the engine exhaust. The method has been re?ned with the inclusion of an annular aqueous denuder to the tube which permits dry ?lter samples to be obtained without addition of dilution air. Tailpipe ?lter samples may then be directly collected in hot and water-supersaturated exhaust gas ?ows from water bath-cooled coal mine engines without the need for dilution air. A primary means to reduce environmental levels of diesel particulate matter (DPM) exposure to miners is to reduce the amount of DPM emission from the engine. A quick and economic method to estimate engine particulate emission levels has been developed. The method relies on the measurement of pressure increase across a ?lter element that is brie?y used to collect a DPM sample directly from the engine exhaust. The method has been re?ned with the inclu­sion of an annular aqueous denuder to the tube which permits dry ?lter samples to be obtained without addition of dilution air. Tailpipe ?lter samples may then be directly collected in hot and water-supersaturated exhaust gas ?ows from water bath-cooled coal mine engines without the need for dilution air.

To alleviate the hazard to personnel and danger to equipment caused by fires on large, mobile vehicles. The Approach: A system which automatically senses a fire at its early stage of development, warns the driver of the danger, and activates fire extinguishers in the zone of combustion, How It Works: The automatic fire protection system utilizes both thermal and optical sensors to detect the heat or light given off by a fire in the area of concern (Fig. 1). The system warns the driver of the hazard and then automatically extinguishes the fire with pressurized S-C class powder. The system can also be activated manually from the operator's cab or from ground level. Further, the automatic sequencing of the system can be manually overridden by the driver if he determines that the fire sensors have malfunctioned to cause a false alarm.

Jan 1, 1974

By Frank G. Horino

A rock mechanics program (composed of laboratory and field tests) was initiated by the Bureau of Mines in an effort to determine the causes of pillar instability at the Fletcher mine, near Bunker, Mo. Compressive strength, Young's modulus, shear strength, and the angle and coefficient of internal friction were determined on drill cores obtained from 16 different locations in the mine. Results of the laboratory tests showed that highly mineralized zones and brecciated zones in pillars could significantly affect pillar strengths and stability in locations where extraction ratios exceeded the normal design ratio of approximately 78%. High-angle fractures that were present in Some locations also may have contributed to pillar deterioration. In the field tests, in situ stress determinations were made in one pillar to establish the pillar-loading conditions and to evaluate the stability of the pillar. Continued monitoring of stresses in the pillar showed a gradual decrease in compressive stress, indicating that the pillar was probably in the postfailure state. A second stress determination was made in a vertical hole in the underlying igneous rock that was exposed on one section of the mine. Horizontal stresses were compressive and larger than would be expected from gravity loading.

Jan 1, 1978

The U.S. Bureau of Mines conducted a laboratory study to determine what effect use of water-jet-assisted cutting has on frictional-ignition suppression. A single bit with a steel tip, installed on a rotating drum, repeatedly made 22-in-long cuts in a block of Berea sandstone. The drum was operated in an enclosure that contained an explosive methane-air mixture. High-pressure front-mounted water jets operating at 2,000 to 5,000 psig and low-pressure rear-mounted sprays operating at 80 psig were used; the number of ignitions that occurred with each type of spray was compared. The rear-mounted spray was more effective for preventing frictional ignitions than the front-mounted water jet.

Jan 1, 1989

By W. W. Adams

The year 1937 was signalized by increased employment in the metal-and nonmetal-mining 4 industry of the United States. Measured by the number of men working, there was a 17-percent gain in employment compared with 1936. In total number of man-hours worked at all mines, the gain was slightly over 18 percent. Hazards connected with mining resulted in more accidents to the workers than in 1936, but the increase in number of accidents caused only a slight rise in the accident rate because of the much larger increase in the number of man-hours worked. In fact, the fatality rate per million man-hours of exposure was lower in 1937 than in 1936, but the rate for nonfatal injuries increased slightly.

Jan 1, 1940

By Charles Will Wright

The purpose of this paper is to present briefly certain preliminary results of the study of mining methods by the United States Bureau of Mines; to show the relative importance of each method in terms of tonnages mined and man-hours consumed; to give to the mining engineers and particularly to the young student of mining a better understanding of the principal mining methods; and to indicate changes now in progress and to present suggestions for improvements in the art of mining. Questions of mine development and details of underground practice such as drilling and blasting, loading, hauling, hoisting, ventilating, pay systems and mine management are omitted, as these have been or will be discussed in other bureau publications.

Jan 1, 1931

By M. R. Geer

All the coal lands in Alaska are publicly owned, and the Federal Government is the principal consumer of coal. Therefore the Government has long been concerned with the wise utilization of the coal reserves of Alaska as well as with the availability of coals meeting the specifications for use in various Government installations. Coal preparation plays a key role in both of these areas of interest. The proper choice and operation of coal-washing equipment permits the mining of inferior deposits, minimizes waste of coal in preparation, and assures a prepared product of the best quality obtainable from the raw coal. Thus, from time to time, the Bureau of Mines has made washability examinations on most of the coals mined in Alaska. Generally, these examinations were made when new mines or new beds were opened, when construction of new preparation plants was being considered, or when the operation of existing plants could be improved by better knowledge of the raw coal. The purpose of this report is to bring together all the washability data available on the coals of the Matanuska Valley and Beluga River fields. The pattern of energy development for the rapidly growing Anchorage area is not clear at this time. Formerly coal was the only fuel available for large-scale space heating and power generation. More recently both oil and natural gas have entered the market, and several hydroelectric projects have been completed. Additional major hydroelectric projects are being considered. The role that will be played by coal in this competitive energy market is uncertain. However I if coal is the fuel used in future power plants or industrial installations, the information contained in this report will be useful in indicating the quality of the coals that can be supplied and in selecting proper preparation techniques.

Jan 1, 1962

By Michael S. Wieland

The work-principle method was developed for theoretically resolving toxic fumes from non-ideal charge formulations. The whole description of a wanted process refers to macroscopic changes resulting from removing and imposing constraints that work one at a time to chronologically render trajectory terminal (key) states. The trajectory resolution utilizes a thermodynamic quasi-potential or negative work function, and numeric results require some appropriate standard thermodynamic (equilibrium) reaction code TDRC. The underlying method is unable to restrict reactions, tailor the work output or resolve states within the trajectory transitions, so the trajectory terminology is used somewhat figuratively. The work-principle model has the working fluid (reaction material) interacting with a tremendous reservoir (chamber air and walls), while forecasting the work performed upon a mechanical agent. Within the underground test chamber, the widening fume zone undergoes a decline in temperature, a reduction in reaction rates, resulting in out-of- equilibrium circumstances at the Q*-point, representing the measurement state. Rather than coping with the hard issues of non-equilibrium, the toxic fumes are resolved numerically for the Z-point, rendered by a zero-net- interaction energy constraint. Though other techniques require complex equation-of-state EOS for the whole trajectory, the work-principle formulation eludes the issue, requiring an EOS that works just for the terminal-state. Under the circumstances, the Z-state is reconcilable with the ideal-gas domain, and relevant TDRC results yield the restricted state in a numerical way for different charge formulations. The work principle makes it hard to remedy or to tamper with the resulting Z-point fumes: non-macroscopic trajectory readjustment is forsaken, terminal states are results rather than stipulations, and resetting the EOS formula constants would be ineffectual. Though the non-equilibrium portion remains unresolved, it is noteworthy that the work principle rigidly fixes the Z-state, thereby reducing the uncertainty for rendering reaction-rate models characterizing the non-equilibrium Z-Q* transition. Though more refinements are needed, some Z-point fume results are included to illustrate the threshold (minimum) resolving capacity of the work- principle formulation.

By R. P. Maloney

The Bureau of Mines conducted a reconnaissance of the less accessible parts of the Beluga River coalfield in August 1957 to determine, if possible, which areas were most favorable for developing large reserves of coal suitable for open-pit mining. Several outcrops of subbituminous coal were observed within an area about 30 miles long and 3 miles wide; neither the length nor the width of the coal-bearing area was delineated by the examination. Coal beds 30 feet thick or more outcrop at two places, and beds 5 to 20 feet thick or more outcrop fairly abundantly along the Beluga River and its tributaries The coal measures appear to occur in a series of folds. The overburden comprises glacial gravels and poorly cemented sandstones and ranges from 20 to 400 feet in depth. Few partings were seen in any of the coal beds. Samples ranged in calorific value from 6,240 to 8,246 B. t. u. on an as-received basis. Adequate water is available for stripping by hydraulic methods.

Jan 1, 1958

By J. G. Kirby

According to the Bureau of Mines annual survey, there were 319 petroleum refineries in the United States as of January 1, 1957 capable of processing 9,123,674 [ ]-barrels of crude oil daily. This was the first time in eleven years that the total number of refineries increased. The crude throughput capacity of the refineries increased 491,284 barrels daily (6 percent) above the January 1, 1956 capacity. The East Coast and Texas Gulf Coast refining districts accounted for 60 percent of the additional capacity installed. Three new refineries were put into operation on the East Coast during the year with a total daily crude throughput capacity of 154,434 barrels while the other refineries in the district report a net loss in capacity, installing equipment capable of processing 140,000 barrels, but dismantling equipment with a capacity of 150,100 barrels. In the Texas Gulf Coast district, one new refinery with a daily crude oil capacity of 5,000 barrels was placed in operation in 1956 and 143,700 barrels of crude capacity was added to existing refineries. The capacity of the average refinery to process crude oil increased from 27,145 barrels daily to 28,601 barrels in 1956.

Jan 1, 1957

By J. A. Woolf, E. S. Leaver, A. P. Towne

"INTRODUCTION A report giving experiments dealing with factors affecting the floatation of the most commonly occurring silver minerals was published years ago. At that time we could not obtain suitable samples of many of the so-called sulfo-salts of the base metals, which are generally silver--bearing and which comprise an appreciable percentage of the natural silver ores. Since Leaver and Woolf's work was published, samples of impure tennantite and enargite have been obtained, and considerable experimental flotation work has been done with synthetic mixtures prepared from these samples. During the present national emergency, research dealing solely with the recovery of gold and silver must necessarily be curtailed. However, many deposits of strategic minerals and critical base metals contain an appreciable amount of gold and silver, the recovery of which would aid greatly in recovering the strategies by taking care of a considerable part of the cost of treatment. Because of this, the recovery of precious metals should not be overlooked entirely. As the Bureau of Mines is now utilizing all of its facilities for the development of increased domestic productions of strategic and critical minerals, this is the last report not concerned primarily with such minerals that will be published until the war ends."

Sep 1, 1942

By Jack I. Paige

The devitrification of lithium silicate glasses was studied to determine the effect of annealing temperature, composition, and additives on nucleation and crystallization. High-purity glasses, prepared from reagent-grade chemicals, had close to optical quality when prepared by a vacuum induction melting method developed during this research, The progress of devitrification was traced by differential thermal analysis and thermal expansion for those lithium metasilicate-silica compositions containing 80 to 90 percent silica. Microscopic studies of glasses partially devitrified at various temperatures and annealing times indicated that the primary initial mode of formation of individual crystals ,vas from densely crystalline zones that filled in as crystallization advanced Of the additives tested, calcium, potassium, and sodium helped promote devitrification with the least cracking or surface deformation. Tin oxide was most effective in reducing volume contrast ion during devitrification, but was not ClS effective in preventing cracking as calcium or potassium additions.

Jan 1, 1965

By John F. McCoy

The United States Bureau of Mines (USBM) awarded a contract to Foster-Miller Associates, Inc. (FMA) to develop guidelines for designing, constructing, stocking and maintaining rescue chambers in underground mines. This report develops information and recommendations which could be used by a mine operator who desired to install a rescue chamber. Volume I covers the following major areas: atmospheric life support, configuration and construction, chamber location, power and lighting, equipment and supplies, communications, and psychological aspects and training. Volume II contains the following appendices: History of Barricading, Chamber Pressurization Considerations, Diffusional Infiltration of Gas, Compressed Air Storage, Location Examples, and Psychological Aspects.

Jan 1, 1983

By R. Vernon Helm

Four tables listing values for the various physical properties of those sulfur compounds most likely to occur in petroleum and petroleum products are given herein. The data necessary to bring the first compilation2/ in this subject up to date are given in table I -Revised and Additional Data, which includes boiling points, refractive indices, densities, and freezing points. Tables 11-, III, and IV are published for the first time and include refractive indices for the F, C, and G' lines of hydrogen and the helium D:3 line; surface tensions and viscosities, and refractivity intercepts, specific dispersions, specific refractions, and parachors. The need for information concerning the sulfur compounds in petroleum is becoming-more urgent because of the necessity of refining larger quantities of high-sulfur crude oil to meet the rising demand for petroleum products. For a number of years the Bureau of Mines has been engaged in research to make available more information concerning the properties of the sulfur compounds in petroleum. The petroleum industry has recognized the value of such studies, and as a result the American Petroleum Institute has established Research Project 48A to study sulfur compounds. The investigations under this Project are to be done in Bureau of Mines laboratories as a cooperative project in connection with the work already started.

Jan 1, 1949

By W. L. Falke

Procedures in which manganese compounds are reduced and the metal is volatilized and selectively condensed, a hitherto neglected area, were investigated. More than 95 percent of the manganese was recovered from high-melting-point ores whether vacuum volatilization or atmospheric pressure volatilization was used, but neither process is economically attractive under present price-cost conditions.

Jan 1, 1966