Search Documents

By W. L. Dare

This report is one of a series published by the Federal Bureau of Mines to describe methods and costs of mining uranium on the Colorado Plateau. The Navajo Uranium Division of Kerr-McGee Oil Industries, Inc., mines uranium from several deposits of carnotite-type ores, which lie buried in the Lukachukai Mountains on the Navajo Indian Reservation, Apache County, Ariz. The country is rugged and isolated Constructing and maintaining roads has been a continuous task. The ore bodies occur within the Salt Wash member of the Jurassic Morrison formation and are similar to other such deposits on the plateau. The current mining activity in the Lukachukai Mountains is a result of uranium-ore discoveries in 1949, although the Navajos undoubtedly knew of the outcrops of yellow uranium minerals long before that time. The ruggedness of the country and the heavy soil cover over much of the surface hampered prospecting, but probably the main reason the ore was not found sooner is that no one took the trouble to look for it in the Lukachukai Mountains.

Jan 1, 1961

By Amanda S. Azman

It is known that exposure to high sound pressure levels can lead to permanent hearing loss; however, many workers, in mining as well as other occupational sectors, frequently receive hazardous noise exposures. The National Institute for Occupational Safety and Health (NIOSH) recommends using a criterion level of 85 dB(A) for implementation of hearing loss prevention programs1. But, despite engineering and administrative controls, workers continue to exceed their recommended daily noise dose. Hearing protection devices are worn as a final defense against noise overexposure, but many workers have difficulty communicating or detecting warning signals while wearing them. New electronic technology has been integrated into conventional hearing protectors to allow for some degree of sound restoration. Research is currently being carried out within NIOSH, Pittsburgh Research Laboratory (PRL) to evaluate the performance of sound restoration hearing protectors. Due to certain features of the devices, such as their non-linear performance and possible manipulation of electronic settings, there are obstacles to testing them using the existing standard hearing protector test methodology (ANSI S12.42-1995 and ISO 4869-3:1997). These and other issues related to testing these devices are outlined within this paper, and possible solutions are discussed. Measures of attenuation properties have been done on a set of the devices and preliminary findings indicate that new test methods, or at least modifications of existing methods, must be developed to accurately determine device performance. Furthermore, it is necessary to know not only the attenuation properties of such devices, but also the degree to which speech intelligibility or recognition of warning signals is preserved, as compared with conventional hearing protectors. As additional data is collected a more accurate and reliable test methodology will be developed, and a more comprehensive picture regarding device performance will be determined and disseminated.

Jan 1, 2008

By R. R. Sayers

The contemplated use of dichloro-difluorco methane in domestic and commercial refrigerating appliances and in air-conditioning equipment for public buildings and possibly homes, brims attention to the health hazards involved in a wide potential exposure of the public to vapors of another new product, and for the first time to vapors of an organic fluorino compound. The objective in the development of this new refrigerant, however, has been the mitigation of health and explosion hazards in automatic refrigeration, and accordingly these factors have been given primary attention. Early in the development, the Bureau of Mines as requested to make a laboratory study of the toxicity and potential hazard, and it was ca the oasis of the results is of this work and the results of a preliminary investigation made in another laboratory6 that the compound has been selected for commercial use. The investigation conducted by the Bureau of Mines is still in progress, enough information has been obtained to indicate the order of the toxicity and the magnitude of the health hazards involved in the use of dichloro-difluoro methane as a refrigerant. The following is a summarized report of the work completed to date:

Jan 1, 1930

By Lloyd A. Morley

This Bureau of Mines publication presents a comprehensive review of mine electrical power-system theory and practice. It discusses fundamental theory and the vital aspects to be considered in planning and designing mine electrical power systems. The report is divided into three major sections. The first presents the history of electricity in mining and the fundamentals of electrical phenomena and components. The second focuses on power-system components: motors, grounding systems, cables, and protective equipment and devices. The final section includes mine power-center equipment, switchhouses and substations, batteries, and mine maintenance.

Jan 1, 2003

By John P. Wagner

The details of a three-phase study (total time period of 12 months) entitled ?Fire Alert Systems for Metal and Non-Metal Mines,? are presented. Phase 1 consists of a state of the art survey on fire detection devices and gas sensing techniques. Phases 2 and 3 include laboratory screening and systems concepts testing on various detectors classified as products of combustion, optical view-field and contact (or thermal) types under incipient and flaming combustion conditions. Recommendations for a mine fire detection system to protect shaft, sealed off or mined out (from spontaneous combustion of sulfide containing ores and cellulosic materials), and fuel storage areas are also included. me principal problem area noted during Phase 1 study is the high expected occurrence of false alarming of products of combustion detectors (POC") subjected to normal mining operations---diesel vehicles and equipment and shot firing or blasting operations. Simultaneous gas sensing of either the ratio of CO/NOx or CO2/NOx with detection of one or more fire signatures (smoke, radiant energy, or heat sensing) is the recommended approach to discriminate against these operations.

Jan 1, 1975

By D. Harrington

The primary objective of this paper is to discuss the hazards and furnish a list of recommendations for the safe operation of quarries and related works. They have been compiled from Bureau of Mines publications covering the safety experience of engineers before and during the year in the mineral industry,5 from a publication of the National Safety Council, Inc.,6 from explosives recommendations made by various explosives manufacturers,7 and from suggestions obtained from quarries visited. The second objective is to describe and illustrate safety devices, practices, and quarrying methods. The quarrying and related industries of the United States had a lower accident-frequency rate than either the metal- or coal-mining industry as reported for 1942.8 However, the quarry industry ranked eleventh in 15 major industries during 1942 in lost-time accident fre¬quency; metal mining ranked fourteenth and coal mining fifteenth.

Jan 1, 1950

This Information Circular describes the Bureau of Mines Minerals Availability System (MAS), presents the Resource Classification Manual used for information input to a computer file, and discusses the methods of collecting and assembling background material' basic to coding the data.

Jan 1, 1974

By John W. Nebgen

This report contains findings from a U.S. Bureau of Mines study concerning the inhibition of acid mine drainage formation from underground coal mines. A series of experiments was performed in which three different pyritic materials (wastes from coal production plants) were evaluated using several candidate inhibiting agents. Data obtained from the inhibitor-treated pyrites were compared with data from control experiments in which untreated pyritic wastes were used. The experiments were conducted by placing treated and untreated pyrite in columns, passing moist air through the columns to promote oxidation of pyrite, and washing the columns weekly to collect oxidation products for analysis. Experimental results indicate that quantities of acid mine drainage can be substantially reduced if soluble iron III (ferric) ion is controlled. The best inhibitors are neutral or alkaline siliceous materials such as fly ash, blast furnace slag, portland cement, and cement kiln dust. These materials appear to insolubilize iron III species to make them unavailable for reaction with pyrite. The data strongly suggest that the soluble ferric ion aqueous is a key oxidant for pyrite to produce acid mine drainage. The role of aqueous ferric ion as an oxidizing agent is substantiated further by data obtained using metallic iron (nails) as an inhibitor. The iron nails tended to keep the soluble iron in the iron 11 (ferrous) state. Experimental results indicate that sulfate and acidity levels are reduced when pyrite is in contact with the metallic iron.

Jan 1, 1979

By Robert L. Lagace

This final report documents the work done by Arthur D. Little, Inc. (ADL) on behalf of the U.S. Bureau of Mines, Pittsburgh Mining and Safety Research Center (PMSRC), on Contract H0122026 (which began in August of 1971). Under this contract ADL provided technical assistance to the Bureau on a task basis on virtually all aspects of the Bureau's programs related to present and planned emergency and operational communications and miner location systems for underground coal mines. The work consisted of independent investigations, analyses, experiments, breadboard and prototype hardware development, workshops and technology transfer seminars on mine communications, and on-going evaluations and guidance related to the Bureau's contracted programs on electromagnetic noise, mine communications systems, and trapped miner location. This final report documents the work in two volumes, Volume I, "Emergency and Operational Mine Commun¬ications," and Volume II, "Seismic Detection and Location of Isolated Miners." The Tables of Contents of both Volumes are included in each Volume.

Jan 1, 1974

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1980 was $328.6 million, a decrease of $7.8 million from 1979. Cement, crushed stone, lime, clays, and sand and gravel continued as the major commodities produced. Alabama led the Nation in the production of crushed marble; was second in bauxite; third in native asphalt, ferroalloys, kaolin, and oyster shell; fourth in dimension marble, masonry cement, and bentonite; and fifth in fire clay and lime. Alabama ranked in the top 20 States in total value of non-metallic minerals produced. Adverse economic conditions in the construction and metals industries impacted on the minerals industry in Alabama. Mineral producers supplying raw or finished materials to these industries experienced periodic reductions in sales during the year. Unit price increases did not keep up with inflation.

Jan 1, 1982

By Daniel Harrington

On the night of June 8, 1917, the flame of a carbide lamp accidentally set fire to the uncovered and frayed insulation of an armored power cable near the 2,400-foot level of the North Butte Mining CO.'s Granite Mountain shaft. How this, insulation accidentally became exposed is explained on page 15. The highly flammable oiled fabric set fire to the shaft timbers, and as this is a downcast shaft the fire spread with great rapidity, soon filling the mine workings with smoke and gas. At the time 410 men were working underground, 247 of whom escaped by various means, but most of the 163 remaining were probably overcome soon after the fire started, and perished. Only two men were actually burned. The cause of the disaster was purely accidental. The immediate effect was the unexpected reversal of normal conditions; the ultimate effect was great loss of life and the destruction of the main hoisting shaft, putting it temporarily out of service. The work of rescue and fire fighting continued eight days. The following pages present an attempt to draw some practical conclusions and suggestions from this disaster. The property of the North Butte Mining Co. consists of about 220 acres in the northeastern part of the Butte district, Montana. Next to the Anaconda Copper Mining Co. it is the largest producer of the district. In 1916, the year before the disaster, there were 1,160 men employed. The output was 560,947 tons of ore, which yielded 24,498,181 pounds of copper, 1,047,063 ounces of silver, 1,712 ounces of gold, and 412,953 pounds of zinc. The profit was $2,479,595. The total development work for that year was 21,694 feet. During the first half of 1917, the year of the accident, the daily tonnage of ore averaged 2,000, an increase of 400 tons over that of the year 1916.

Jan 1, 1922

The accompanying supply/demand flow diagrams and 10-year tables for mineral and fuel commodities present essential data required by government, industry, and others to formulate policies and programs that can help assure an adequate and continuing supply of mineral raw materials. The 10-year data base terminates with 1973 figures because adequate world information was not available beyond that date. Moreover, 1974 was an anomalous year with respect to prices, supply, and demand for many commodities. The selected mineral supply/demand tables and flow diagrams comprise but one "output" from the massive body of "information and data collected and com-piled by the Bureau of Mines on a continuing basis covering mineral production consumption, prices, shipments, imports, exports, and stocks, as well as industry activities in all States and abroad.

Jan 1, 1975

Nineteen eighty-seven was a year of significant change in the Bureau of Mines-change to help it better adapt and respond to the wide range of new challenges facing the U.S. mineral industry. The Bureau has been regarded as the world's premier mineral information and research agency. Its authoritative, comprehensive data and its pioneering research have contributed significantly to the minerals position of the United States. Yet no organization in today's complex, dynamic world, with its rapidly advancing technologies, can afford to rest on its laurels. Mission and program must be constantly fresh and relevant to the day's issues and problems. Moreover, rather than reacting to events, the organization must strive to anticipate and prepare for them. It must have a sense-a vision, if you will-for the future.

Jan 1, 1987

By B. K. Shibler, W. G. Sandell, G. M. Potter, H. D. Snedden

"INTRODUCTION During the course of the investigation of the occurrence of manganese deposits in the western United States, examining 'engineers of the Bureau of Mines collected samples from seven manganese properties in Grand and beery Counties, Utah. These were supplemented by five samples submitted by property owners. Since all of the ores were too low-grade for use in producing ferromanganese for steel manufacture, some means of beneficiation was required to produce marketable concentrates, and metallurgical studies were made on each of the samples.Most of the ores Investigated are similar in one respect: At least part of the 'manganese oxide areas contains minute inclusions of gangue. This occurrence materially enhances the complexity of the ore, partly by .increasing the complexity of mineral association, but largely through making manganese-quartz liberation more difficult. In such ores, there is a marked tendency for the manganese minerals to be retained as shells or coatings on the surfaces of quartz particles when crushed. Particles of this type represent considerable loss of manganese in tailing, if gravity-concentration methods are employed, or tend to' float, thus carrying an appreciable quantity of gangue into the concentrate, if treated by flotation.Plus 48-percent manganese sinters were made from some of the ores tested, but, in general, intimate association of manganese minerals with silica limited the degree of beneficiation attainable."

Dec 1, 1947

By Chas. F. Jackson

This circular is an abstract of a manuscript-completed in August 1932, which cannot be published in its entirety due to lack of printing funds. It was originally planned to publish the manuscript as one of a series of bulletins dealing with the mining and milling of ores of the principal metals. Because of the common association of lead and zinc minerals in many ore deposits, and because a considerable proportion of the zinc produced in this country is obtained as a by-product of lead mining or vice versa, it seemed necessary to treat the mining and milling of lead and zinc ores in the same volume.

Jan 1, 1934

By H. E. Harris

An extensive experimental program was carried out to determine the variability of respirable dust samplers and to determine whether area dust sampling is feasible in coal mines. For sampler variability, it was found under laboratory conditions, that a single dust measurement could be as much as 0.30 mg/M3 from the true value at the 95% confidence level. Under actual underground mining operations, this difference could be as much as 0.52 mg/M3 in the 0 -5.0 mg/M3 range. The results from dust sampling on 175 production shifts involving over 2,500 on-man and area dust samples showed that area sampling is viable, but the field investigation did not establish necessarily where the best area locations were.

Jan 1, 1976

By Walter R. Storms

"The New Mexico potash exploration described herein was begun in February- 1944 by the Federal Bureau of Mines with the object of determining the amount of potash ore in the United States Potash Reserve in Eddy County, N. Mex., by exploring the deposit from the surface with vertical drill holes. The work was completed in October of the same year after 16 holes had been drilled on the reserve and in the immediate vicinity.The Potash Reserve is located in secs. 26, 27, 34, and 35, T. 20 S., R. 29 E., Eddy County, N. Mex., about 14 miles northeast of the city of Carlsbad. Drilling was done in secs. 26 and 35 of the reserve, in sec. 14 to the north, and secs. 25 and 36 to the east. All work was done on Government-owned, unleased land.The reserve may be reached from Carlsbad by traveling northeast by automobile for about 14 miles on paved U. S. Highway 62. This highway passes through the southern part of the reserve. Other parts may be reached by a State highway which passes along the eastern side of the area, then by poor dirt roads to various drilling sites. A branch of the Atchison, Topeka and Santa Fe Railroad also passes across the southern part of the reserve en route from Carlsbad to the plant and mine of the Potash Co. of America, a few miles northeast of the Project and 22 miles from Carlsbad.Work on the project was greatly facilitated by the help of Ralph H. King, associate geologist, R. K. Bailey, geochemist, H. C. Spicer, geophysicist, Hope Bunker, junior geologist, and R. H Allport, district mining supervisor, all of the Federal Geological Survey; and Charles H. Johnson, who at that time was district engineer for New Mexico for the Mining Branch of the Bureau of Mines."

Apr 1, 1946

By Floyd R. Hertweck

This Bureau of Mines publication contains analyses and related source data for 349 natural gas samples from 26 States and 2 foreign countries. The 3 samples from foreign countries and 339 of the U.S. samples were collected during calendar year 1983. The remaining seven samples were collected earlier, but releases granting permission to publish were not received until 1983. All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by the mass spectrometer and chromatograph. The results of these investigations are published annually to make the information available to the petroleum industry and the general public. Twenty-seven publications have presented the results of 13,332 gas analyses made prior to 1983. The first three bulletins (1-3)3 contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960; these bulletins have been supplemented annually by information circulars (4-17, 19-24, 26-27) containing 8,104 analyses of sam¬ples collected since 1960.

Jan 1, 1984

By L. C. IlsLey

Explosives have been fired electrically for several decades. Mountains have been tunneled, deep shafts sunk, extensive coal and metal mine workings excavated and, in times of war, railroads, buildings, bridges, and fortifications have been destroyed by means of electrically fired explosives. Modern engineering depends so much on explosives that their safe and efficient handling and especially their detonation are of prime importance to all those connected with the use of explosive agents. Electric shot-firing is only one method of igniting explosives, but it is rapidly spreading and because of certain inherent safety features should be encouraged. Data collected by the Bureau of Mines indicate that in the United States a large percentage of the blasting in quarries, shafts, and tunnels, and from 15 to 25 per cent of the blasts in mining operations, are set off electrically. The Bureau of Mines is interested in electric shot-firing because of its use in mining, and especially because electric methods, when properly applied, are undoubtedly safer than other methods commonly used.

Jan 1, 1926

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director's offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting & Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. "V. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K Thomson, W. G. Derby, and the assistants of the writer, K. 1V.McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the aid of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate anyone method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916