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Studies of coal reserves have shown that the total augerable reserve base for the United States is estimated to be five billion tons under the current state of mining technology; the potential reserve base at 850-ft penetration is estimated at 20 billion tons. It is with the idea of improving coal recovery, a basic objective of Project Independence, that new concepts, such as modifications and improvements in current machines and development of ways to recover pillars left by current augering, are required. Unless recovery is improved, these potential reserves amount to lost coal.

Jan 1, 1975

By F. F. Aplan

Separation of the slightly soluble minerals (Ksp? 10-10), one from the other is one of the more difficult tasks confronting flotation engineers. This study has focused on means of separating such prominent members of this class as scheelite, fluorite and calcite from one another. Some experimental work has also been done on the minerals magnesite, dolomite and apatite. Carboxylic acid-type collectors are commonly used industrially to float all of these minerals. Thus, the problem at hand is to ascertain means of achieving selectivity between minerals known to respond rather similarly in flotation. Four techniques have been proposed for the separation of minerals of this class from each other: 1. Control of potential determining ions 2. Use of stereo-specific collectors 3. Use of flotation rate differences 4. Use of selective activating and depressing compounds. This study was directed toward a cursory evaluation of each of these techniques, and each was found to be a possible method of achieving selectivity. Stereo-specific collectors -- those whose parking area may closely match the available adsorption site on one mineral but not on another -- are a possible means of achieving selectivity between scheelite, fluorite and calcite. Stereo-hindered carboxylic acid salts and sulfonates all show selectivity between the three minerals tested. Separations also appear to be possible by the controlled use of the lattice ions (e.g., Ca and [W0=4] for scheelite, CaW04), H+, [OH-, C0-3 and HCO=3]; all of them ostensibly potential determining in the systems studied. Flotation rate differences of the minerals as a function of pH under conditions of starvation collector usage also showed promise. Scheelite and fluorite float most rapidly with sodium oleate in slightly acidic (pH 4-7) solutions whereas calcite floats most rapidly near pH 10. Use of Mn++, Pb++, or other heavy metal hydroxy complexes as activators was seen to effect each of the slightly soluble minerals differently. This is in sharp contrast to the oxygen containing, relatively insoluble minerals, where all minerals respond in a similar manner to such activation procedures. Results indicate that all four methods outlined above may potentially be used to achieve flotation separation of the slightly soluble minerals. More extensive research should be undertaken to detail the spcific applicability of each of the procedures and to make a more complete evaluation of the effect of collector type and concentration, mineral type, pH and size effects.

Jan 1, 1983

By John C. Edwards

A fire location computational model was developed by the U.S. Bureau of Mines. The model can determine all the possible paths in a mine that smoke can travel from a fixed fire source to a smoke detector. The associated FORTRAN computer program can be utilized to determine the minimum travel time from a source fire to a smoke detector. The difference in travel time from an isolated fire source to two or more detectors can be used to isolate those airways in which the source fire is located.

Jan 1, 1990

By D. G. Puglio

This Bureau of Mines study covers 25 underground mines that were active in the Upper and Lower Freeport and Lower Kittanning coalbeds in 1976. The coal ranges from low to medium volatile in rank; its primary use is for steam generation. Seven mines emit more than 100,000 cfd of methane gas; those mines are the deepest and largest producers. The methane gas content of three core samples of the Lower Kittanning coalbed was estimated by the direct method. A sample from a depth of 320 feet contained 0.5 cu cm of gas per gram, at 620 feet there was 0.8 cu cm of gas per gram, and at 1,060 feet there was 11 cu cm of gas per gram. These results suggest that methane control problems will be encountered in the future as deeper coal is mined.

Jan 1, 1979

By Vernon C. Davis

"INTRODUCTION This report describes the work done and presents the data obtained from limited diamond drilling at the lead-zinc deposits cf the Belle Eldridge Gold Mines, Inc., in Lawrence County, S. Dak. during the summer and fall of 1943. The work was undertaken in an effort to increase reserves and step-up production of zinc and lead so vitally important to the war program.The geology, topography and existing mine workings were mapped and studied. Subsequently, six vertical core-drill holes were put down from surface sites.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our natural resources to the end that they make the greatest possible contribution to national security and economy. The Mining Division, Lowell B. Moon, chief, conducts preliminary examinations, does the actual investigative work, and prepares the final report. The Metallurgical Division, Oliver C. Ralston, chief, analyzes samples and makes beneficiation tests, if such are necessary.Special acknowledgment is made to John Paul Gries, geologist, South Dakota School of Mines, for mapping and interpretation of geology and topography, logging of cores obtained, and his assistance in guiding the drilling."

Mar 1, 1948

By Jeffrey H. Welsh

The Bureau of Mines studied the use of computerized, continuous, remote monitoring systems for safety from power system faults in underground coal mines. In this report the need to improve protection against power system faults is documented, and types of faults are identified. The relationship between mine safety regulations and computerized, continuous, remote monitoring is analyzed.

Jan 1, 1983

By Albert H. Clough

The West Lynn Canal subarea of the Juneau Mining District (JMD) is defined by Lynn Canal on the east, Davidson Glacier to the north, Icy Strait to the south and the Glacier Bay National Park Boundary to the west (figs. C-l and C-2). This area extends along the main-land west of Juneau (across Lynn Canal) northerly, to approximately 20 miles south of the city of Haines. The only roads in the area are relatively new logging roads at the southern end constructed to support a U.S. Forest Service timber sale. There is also local road access near the community of Excursion Inlet. Access to the remainder of the region is either by boat, aircraft, or 'foot. Helicopters provide the only time effective access to all but the coastal parts of the West Lynn Canal subarea. Coastal areas may be reached by small boat or float aircraft. There is an unimproved dirt airstrip just north of the mouth of the Endicott River. This airstrip is suitable for use by light aircraft. The subarea lies within the Tongass National Forest and is managed by the Department of Agriculture, U.S. Forest Service. Approximately two-thirds of the forest lands are open to mineral entry under the current Tongass Land Management plan. The remaining forest lands comprise the Endicott River Wilderness area, which is closed to mineral entry. Private lands within the study area are sparse, with scattered homestead tracts along the coastal regions and in the Excursion Inlet area. Sealaska (Southeast Alaska Regional Native Corporation) also has land selections in the southern Chilkat Range. Tidal and submerged lands are owned by the State of Alaska.

Jan 1, 2012

By L. C. IlsLey, Charles M. Means

The descriptive rather than the strictly technical meaning of many of the terms and expressions used in the electrical rules is given in order to assist in their interpге- tation . ALIVE . At a potential measurable with a voltmeter and different from that of the earth or another conductor . (Static charges should be determined with an electrostatic voltmeter . This condition may apply to current - carrying parts , to noncurrent - carrying parts and adjacent material where a failure of insulation has taken place , and to objects having stored or static electricity . ) ALTERNATING CURRENT . A current that changes in direction -- positive or negative-- a certain number of times per second , depending upon the number of poles and speed of the generator . AMMETER. An instrument for measuring current , indicating in amperes . AMPERE . A term applied to denote the rate of current flow . ( Analogous to " gallons per minute " in a hydraulic system . ) APPROVED . Accepted as suitable by a competent committee , board , or organization designated by those adopting the rules . ductors . ARMOR . A steel or equivalent metallic covering for one or more electric con- AUTHORIZED PERSON . Anyone commissioned by the official in charge of the mine or his deputies to carry out certain duties incident to the generation , transformation , and distribution or use of electric energy in the mine , such person being one who is competent within the purpose of the rule in which the term is used .

May 1, 1930

By R. L. Thorne

The Snettisham Peninsula, 30 miles southeast of Juneau, Alaska, was studied by the Bureau of Hines to obtain basic information about the size, grade, and metallurgical characteristics of a large basic intrusive containing titaniferous magnetite. The investigation, which was part of a continuing program to determine the potential reserves of iron and titanium ores in Alaska, included transit and magnetometer surveys, followed by diamond core drilling and metallurgical testing. The magnetic attraction of a part of the Snettisharn Peninsula is noted on early navigational charts prepared by the Coast and Geodetic Survey. Reconnaissance examinations by the Geological Survey and a preliminary dip needle survey by the Territorial Department of Mines indicated the general nature of the basic intrusive, but little was known as to the grade and extent of the magnetite mineralization. The detailed survey by the Bureau of Mines proved an area of approximately 390 acres in which generally high magnetic anomalies with exceptionally high localized anomalies occur. Subsequent drilling across B representative section of the deposit yielded core samples, which assayed from 11 percent to over 45 percent total iron. A large sample of core composited to represent the drilled portion of the de-posit assayed 18.9 percent Fe, 2.6 percent Ti02, and 0.29 percent S, 0.32 percent P, and 0.05 percent v.

Jan 1, 1956

By S. H. Ash

Unusual mining conditions prevail in the State of Washington because the majority of the coal seams lie on extra steep dips, and the roof and floor of the seams are of such a character as to require an excessive amount of timber- ing. The seams as a rule give off a considerable amount of methane, which makes good ventilation imperative. Due to physical conditions, supervision is costly and travel about the workings is difficult. Because of the facts stated, the accident rate has been above the average, and for some time considerable thought has been given the idea of making promotion of safety in and about the mines a responsibility to be shared equally by the employees and the management. With this idea in mind the legislature of the State of Washington, turing March, 1927, passed laws providing that safety committees be selected to function at the coal mines of the State and at the same time recognizing the fact that first-aid education is an integral part of any safety movement; legislation was passed making it mandatory to have all persons in and about the ines trained in first-aid administration. The provisions of the State mining law3 are as follows: "In every mine a general safety committee shall be selected, composed of the mine superintendent or manager of mines, one man selected by the employees or any association of employees in or around said mine, and a third member selected by these two. "The general safety committee shall elect one of the members to act as chairman and one to act as secretary. The duties of the chairman shall be to preside at all meetings of the general safety committee, enforce its rules and regulations and see that its business is conducted in a prompt and business-like manner. The secretary shall keep an accurate written record of the proceedings of all meetings, conduct its correspondence and post notices of regular and special meetings and other matters pertaining to safety. The duties of the general safety committee shall be to investigate all serious and fatal accidents; make bi-monthly.

Jun 1, 1930

By W. P. Yang, L. B. Berger, G. W. Jones

"Any burning carbonaceous material, unless supplied with enough oxygen for complete combustion, will liberate carbon monoxide. Since tobacco in its many different forms consists largely of carbonaceous material, and duo to the conditions under which it is smoked (burned), carbon monoxide should be liberated. That this is true has been shown by Armstrong.***** who found that undiluted smoke from cigars contained in some tests more than 3.00 per cent carbon monoxide, the amount present depending upon the size and closeness of packing of the tobacco during manufacture and on the rate of burning.****** Cigarets gave much less CO, varying from 0.06 to 1.40 per cent. The rate of consumption and carbon content of the tobacco are not g.ven, so that a correlation of the values reported to conditions in closed spaces where people might be assembled are difficult, if not impossible.The Bureau of Mines is interested in the general question of carbon-monoxide hazards from tobacco smoke, mainly with regard to mine ventilation. In non-gaseous mines, especially metal mines, the question arises, whether, if groups of miners are permitted to smoke while working at unventilated faces or entries, would the accumulation of tobacco smoke in these places create an' additional hazards the to carbon-monoxide poisoning. The results should, in addition be of general interest in connection with ventilation of building and inclosed places where people may be assembled and smoking is permitted. The investigation described in this report was made with the above idea in view."

Oct 1, 1923

By T. T. Tomimatsu

This? Bureau of Mines paper discusses the corporate structure dynamics, methods of financing, and financial assessment approaches that should be utilized to evaluate the economic health of the coal industry. It suggests rates of return and other measures of corporate economies necessary to attract capital required to finance emerging coal demand, plus impact of coal sales to total revenues. The study illuminates the activities of 30 selected coal-producing companies, including their subsidiaries or affiliates, that were responsible for approximately 60 percent of the total U.S. production in 1974. The selected firms are not all primary coal producers; many of the larger producer's are classified by the financial institutions as petroleum, metal, and steel producers, public utilities, or chemical industries. The bituminous coal industry is highly competitive as to price, service, and quality of pronuct and is subject to competition from other noncoal energy sources. The top 15 bituminous coal-producing companies mined about 46.6 per-cent of the Nation's total production in 1974, and the balance of approximately 3,885 companies were responsible for the rest of the production. Thus, the U.S. bituminous coal industry is not an oligopoly. Today, about 65 percent of the Nation's total coal production is consumed by electric power utilities and 26 percent by steel, space heating, and other industries; the balance of 9 percent is exported.

Jan 1, 1976

By William A. Beck

Bauxite was discovered in the Springvale district in 1916. About 16, 000 tons was mined in the period 1916 to 1922, but no bauxite mining has been done since that time. The Bureau of Mines explored for bauxite in the district from September 5 to November 18, 1943. During the life of the project, the Bureau of Mines obtained mineral exploration agreements covering a total of 11,330 acres from 50 property owners. A total of 388 holes were drilled on five of these properties and 164 samples were taken and analyzed. The Springvale bauxite district includes an area of about 30 square miles in the northwestern part of Randolph County, Ga. The village of Springvale is in the west central part of the district, and Cuthbert is 8 miles southeast of it (fig. 1).

Jan 1, 1949

By C. M. McKinney

This report contains Bureau of Mines analyses of 291 samples of crude petroleum from the Gulf Coast Area of Louisiana and Texas. Included are 65 analyses from 51 Louisiana fields and 226 analyses from 216 Texas fields. Analyses from the Texas fields include 90 from 58 Upper Gulf Coast fields, 47 from 28 Middle Gulf Coast fields, and 89 from 40 Lower Gulf Coast fields. The analyses represent fields that produced 1,000 barrels or more per day during at least one of the years 19.57 through 1961, with the exception of 23 analyses from the Texas fields. The fields considered are listed by state and geographical groupings, with field names arranged alphabetically within each grouping. The tabulation also includes information concerning the geological sources of the samples. General characteristics of the crude oils and analytical and computed data determined from the analyses are summarized. Crude oil production data are given for the fields for 1960 and 1961 and are cumulative through 1961.

Jan 1, 1963

By Robert H. Bedford

The Rogan-Mallery tin property is in the foothills on the south slope of the Tehachapi Mountains, Kern County, Calif. It was first visited by the senior author in August 1942, and exploration by means of trenching and diamond drilling began in May 1944 and was concluded in August of the same year. Cassiterite, associated with iron-rich gossan, occurs in a limestone roof pendant at places near or at its contact with the underlying granitic rocks. The cassiterite grain sizes range from 20 mesh to 150 mesh. Surface and diamond-drill samples showed tin ranging from traces up to 122.6 pounds per ton. Exploration by the Bureau of Mines included 2,100 cubic yards of trenching and the drilling of 11 diamond drill holes totaling 1,000 feet. Dana Hogan, president of the Rogan Petroleum Co. of Los Angeles, Calif.) brought these projects to the attention of the Bureau of Mines in July 1942, and the following month a Bureau engineer made a preliminary examination in company with Hillard Mallery, of 408 Ruby Street, Redondo Beach, Calif., the man who discovered them.

Jan 1, 1949

By John J. Sammarco

This report details the testing and evaluation of a modular azimuth and positioning system (MAPS) to provide navigational information for a continuous mining machine. Vehicle navigation is part of the U.S. Bureau of Mines research program in computer-assisted mining serving as a tool to increase mining health, safety, and productivity. The Bureau is investigating other navigation systems, but MAPS seems to have the most promise. MAPS was installed on a continuous mining machine. An operator used the machine to cut coal while researchers collected machine and MAPS data. A comparison of MAPS data for xy position and data obtained with an electronic transit showed an increasing error for MAPS. After 30 min of operation, the easting position error was -0.02 m, and the northing position error was 0.019 m; after 60 min of operation, the easting position error was -0.19 m, and the northing position error was -0.26 m. Modifications to MAPS software and to the operational procedure of the machine significantly reduced this error by a factor of 3.7. Researchers continue to reduce these errors.

Jan 1, 1993

By J. A. Eisele

The Bureau of Mines is investigating the recovery of alumina from domestic nonbauxitic resources, including anorthosite. The United States has large reserves of anorthosite, but its aluminum content is less than 50 pct soluble in acid, unless a source of fluoride is added to the acid. A flowsheet that includes leaching with HCl and fluoride followed by crystallization of AlC13.6H20 from the pregnant liquor by HCl gas injection was designed. Approximately 90 pct of the aluminum values were recovered from the anorthosite when a ratio of 0.14 mole of fluorine per mole of aluminum was used. Sodium chloride is cocrystallized with the A1C13.6H20 but is removed by water washing of the Al203 product. A material balance is given based on results of laboratory studies of the unit operations.

Jan 1, 1983

By Corwin L. Cooper

This paper, describing; the milling and cyanidation methods and costs at the Yellow Aster gold mine, is one of a series of papers being prepared by the Bureau of Mines on bold milling practices in the United States. Acknowledgments Acknowledgment is made to the executives of the Anglo American Mining Corporation, Ltd., for permission to publish this article, and to A. W. Frolli, manager, and other members of the company staff, for assistance` in preparing the, paper.

Jan 1, 1936

By Frank B. Fulkerson

A study was made of the economic factors governing silver production in the Coeur d'Alene mining region, Shoshone County, Idaho. Production and other stat is tics were analyzed. It was concluded that if the rapid rise in the open market price that began late in 1961 continues, greater production of the metal should result from the mines of the Coeur d?Alene mining region. However, the output gain would be limited, because costs per ton of ore mined would rise as production was increased beyond optimum capacity. Advances in the price of silver would increase the size of ore reserves by making some marginal ore profitable to mine and by providing greater funds for exploration projects that might result in discoveries adding to the reserves. Output of byproduct silver from lead-zinc mining probably will not exceed 4.3 million ounces, judging from the trend from 1946 to 1961.

Jan 1, 1964

By J. D. Ramsdell

The object of this investigation by the Federal Bureau of Mines was to evaluate the workability, recrystallization characteristics, and mechanical and physical properties of high-purity electrorefined vanadium. The low level of interstitially soluble elements in electrorefined vanadium results in a soft ductile metal which responds readily to cold working by rolling, swaging, and press-forging. Hardness, strength, and resistivity increased with an increase in impurity content, but thermal expansion was independent of impurity content. The work-hardening of vanadium occurs rapidly. Most of the hardness increase occurs in the first 15 pct. of reduction in area. When vanadium is annealed, its hardness increases to a maximum when the annealing temperature is between 200° to 400° C. A sharp decrease in hardness develops as the annealing temperature is increased. An anomaly in the hardness versus annealing temperature curve is present in the 600° to 800° C. range, while all evidence of cold-work is removed at annealing temperatures above 900° C.

Jan 1, 1961