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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 Roy C. Bartholomae

This U.S. Bureau of Mines study found that the performance of the active noise cancellation hearing protector in a reverberant field was mixed. The performance varied when the conditions changed from ideal to nonideal. The active noise cancellation (ANC) component provided substantial additional noise reduction from 125 to 500 Hz for all testing conditions (broadband noise or pure tones both with and without safety glasses). While the ANC under ideal conditions provided additional attenuation from 500 Hz and below, under nonideal pink noise conditions the ANC amplified noise below the 125-Hz third octave band. There was a middle band of frequencies at which the ANC amplified noise levels ranging from 630 to 4,000 Hz. The results for pure tones showed that attenuations were higher but that they followed the same general trend.

Jan 1, 2010

By R. Y. Williams

In this report an attempt is made to discuss the first cost of each of several types of mine-ventilation stoppings, as well as the total annual expense of maintaining a stopping during its required period of service. Such data furnish a basis for comparison of the efficiency of the different types, and are of great importance to an engineer planning the development of a mine. The data given were obtained through an investigation conducted under a cooperative agreement between the Bureau of Mines, the Illinois State Geological Survey, and the department of mining engineering of the University of Illinois. The report itself is published by the Bureau of Mines as a contribution to the literature on safety and efficiency in coal mining.

Jan 1, 1915

By Robert L. Kranz

Mining-induced microseismicity data collected by the U.S. Bureau of Mines in a hard-rock mine were analyzed for spatial and temporal patterns that might prove useful for prediction of rock bursts or assessment of rock mass damage changes. Pattern attributes described and illustrated in the previous report (part 1) were applied to the study of aftershock sequences associated with two different stopes. The aftershock sequences were spatially and temporally fractal, and the fractality was maintained for up to 16 h following a sequence progenitor. This suggests mechanical interdependency among the after-shocks. No statistical difference was found in the distributions of fractal dimensions when comparing two different stopes or when comparing aftershock sequences initiated by blasts or bumps. This suggests a lack of sensitivity to both stress perturbation mechanism and local damage states. However, differences between the two stopes were found in other sequence attributes that support inferred differences in the magnitude of stress concentrations and damage near each stope, and over time as a stope is developed.

Jan 1, 2010

1. Domestic Production and Use: Twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 66% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 25%; Northern States, 29%; and other Southern States, 14%. Output of primary metal in 1973 was valued at $2.2 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1972, building accounted for 28%; transportation 19%; electrical, 13%; packaging, 16%; and consumer durab1es, 10%.

Jan 1, 1974

This is the second of a series of reports on properties of commercial motor fuels made pursuant to a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ These gasoline surveys report results of inspections, in oil-company laboratories, of samples of gasoline obtained by representatives of oil companies from service-station pumps in marketing areas throughout the country. In the present survey are presented inspection data on 239 samples of regular-price gasoline, 166 samples of premium-price gasoline, and 157 samples of third-grade gasoline, a total of 562 samples collected during the summer of 1936.

Jan 1, 1937

This is the second of a series of reports on properties of commercial motor fuels made pursuant to a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data oil motor gasolines sold during the minter of 1935-36.3/ These gasoline surveys report results of inspections, in oil-company laboratories, of samples of gasoline obtained by representatives of oil companies from service-station pumps in marketing areas throughout the country. In the present survey are presented inspection data on 239 samples of regular- price gasoline, 166 samples of premium-price gasoline, and 157 samples of third-grade gasoline, a total of 562 samples collected during the summer of 1936.

Jan 1, 1937

By John F. McCoy

The U.S. Bureau of Mines (USBM) awarded? a contract to Foster-Miller, Inc. 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 Pressuriztion Considerations, Diffusional Infiltration of Gas, Compressed Air Storage, Location Examples, and Psychological Aspects.

Jan 1, 1983

By George T. Krempasky

This report is one of a series of Bureau of Mines Information Circulars dealing with mining methods and costs throughout the United States. It describes drifting, crosscutting, and raising operations at several mines in the Coeur d'Alene mining district, Shoshone County, Idaho. Ore bodies in the Coeur d'Alene district are generally in steeply dipping tabular ore zones, are irregular in shape, erratic in occurrence, and have been extensively mined along the strike and down dip. Because of the extended attitude of the deposits a great deal of development work is required. Drifting, crosscutting, and raising methods are described in this report. Shaft sinking is the subject of another report in the same series.

Jan 1, 1960

By J. W. Thompson

RAILROAD GRANT-MDIERALS. Diatomaceous or infusorial earth when found in such quantity and quality as to render lands containing deposits valuable therefor are mineral lands within the meaning of the mining laws and must be excepted from grants to the Central Pacific Railway Company. Central Pacific Ry. Co., In re, 45 Land Decisions, 223, p. 226. RAILROAD GRANT-CLASSIFICATION, If any evidence of minerals is found upon lands within a railroad grant and the showing is sufficient in the opinion of prudent and qualified persons to warrant further exploration and expenditure, with reasonable prospects of success, then the land can not be classified as nonmineral and is not subject to the grant to a railroad company. But where there is no present indication of minerals nor any geological evidence upon which to base a mineral finding, land should not be classified as mineral, or held for further classification and reserved from the railroad's grant, upon the surmise that future prospects might disclose evidences of minerals. Southern PacUl.c Ry. Co., In re, 45 Land Decisions, 326, p. 329. INDEMNITY SELECTION BY RAILWAY COMPANY, Under section 3 of the act of July 2, 1864 (13 Stat., 365), and the joint resolution of May 31, 1870 (16 Stat., 378), the Northern Pacific Railway Company could take coal and iron land within its primary or grant limits. It could not base an indemnity selection upon the claim that certain land was coal or iron in ;;haracter, as such land was not lost to it as part of the grant. But the company was authorized to select other lands in lieu of those lost because of their mineral character, but the word "mineral" did not include iron or coal, and, accordingly, the railroad company was entitled to take coal lands under its indemnity selection.

Jan 1, 1917

By E. D. Eastman

The basic character of the free energy r data relating to water and the oxides of carbon makes it desirable that the most representative values that can be obtained should be constantly available. The calculations of Lewis and Randall3 retain much of their of original value, but appear to require some modification in the light of more recent work. This paper has been written to incorporate the newer information and to present some estimate of the reliability of the resulting figures. The data upon which the calculations are mainly based are, for these substances, the equilibrium constants of the various reactions involved. The original work relating to these equilibria has, been reviewed and, where possible, weighted to correspond with its probable reliability. The differences in the results of the present from the earlier calculations are partly the consequence of this appraisal and partly of the inclusion of more extensive data, as will be indicated in detail in the succeeding sections.

Jan 1, 1929

By Robert K. Guthrie, James W. Amyx, D. B. Taliaferro

"INTRODUCTION Secondary recovery of oil by water-flooding is practiced more extensively in North Texas than in any other section of the State, and the progress and experience of the operations in that area are of continuing interest to all branches of the oil industry. The first Bureau of Mines report on water flooding in North Texas 7/ chronicled the activities from December 7, 193f', when the Railroad Commission of Texas granted The Texas Co. the first permit to inject water into an oil-bearing sand, through 1944. This second report has been prepared as a supplement to Report of Investigations 3906 to show the progress and expansion of water-flooding. The format of this report is almost identical with what of report of Investigations 3906, except for a few miner changes. For the sake of brevity, certain basic information contained on the first report has not been repealed, and the reader is urged to consider the two reports as corporation writings.The North Texas area, as encompassed by the two reports, corresponds Railroad Commission of Texas Districts 7P and 9. Oil-development operations in the two districts, since oil was discovered in 1904, have resulted in the recovery of approximately 1,400,000,000 barrels of oil from a proved area that has been estimated to exceed 413,000 acres. During October barrels of oil was produces by primary and secondary-recovery methods from 1,746 flowing wells and 25,211 pumping wells, a daily average 6.6 barrels per well. Of this total volume of oil recovered in October 1947, 47,965 barrels (0.87 percent) was recovered from leases on which water-flooding operations were in progresses."

Feb 1, 1948

By Frank B. Fulkerson

Of the about 60 million pounds of aluminum used in the Pacific Northwest in 1960, 40 million pounds or two-thirds was used by 10 companies. One of these companies made airplanes and missiles; one manufactured roofing, siding, and tubing; three produced truck tractors, truck bodies, or truck trailers; two made architectural metal products; one made irrigation and industrial products; one was a general foundry; and one was a shipyard. These companies contributed to regional growth by developing markets outside the area; some have worldwide sales. Aluminum consumption increased at an average rate of 7 percent annually from 1954 to 1960. Airplane manufacture, formerly preeminent in aluminum use, no longer was in first place in 1960. By industrial group, the leading users were manufacturers of building products, 30 percent; airplanes and missiles, 22 percent; truck tractors, truck bodies, and truck trailers; 17 percent; general foundries, 5 percent; ships and boats, 4 percent; mobile homes, 4 percent; other transportation equipment, 3 percent; and irrigation equipment and all other products, 15 percent.

Jan 1, 1962

By L. C. IlsLey

The theory and practice followed by the Bureau of ones in the investigation of electrical equipment4/ made for service in massy mines are of particular interest not only to manufacturers but also to those organizations that deal with safety and inspection at the mines. This publication proposes to discuss the theory, upon which tests of equipment in explosive atmospheres are based and to consider inspection and other matters pertaining to investigations made bar the Bureau in ascertaining whether a machine merits approval.

Jan 1, 1941

By David Burgess

Natural gas is a general term applied to the gas obtained from oil or gas wells. It is the most widely used of all gaseous fuels. The principal disadvantage in the use of this and other gaseous fuels is the difficulty encountered in the storage and transportation of large quantities in the gas state. Handling in the liquid state is possible, but reduced temperatures are required since methane (table 1) is the principal component of most natural gases that are used as fuels. Actually, liquid storage has been utilized both here and abroad;3 however, the Cleveland disaster4 has pointed out the need for a critical evaluation of the hazards involved in the storage of this cryogenic fuel. Accordingly, a program was undertaken to obtain basic data that could be used to assess these hazards. In this report, the factors to be considered in an evaluation of the fire and explosion hazards associated with any fuel are each discussed briefly. These factors are then used to assist in the design of experiments for the evaluation of the hazards associated with liquefied natural gas (LNG) relative to those associated with other common fuels. Experiments have been conducted on the vaporization of LNG, the mixing of LNG vapors with air, the effect of temperature and nitrogen dilution on the limits of flammability of methane in air, the burning rates of LNG and other fuels, flame radiation, and extinguishment of fires above liquid pools. Based on the results of these experiments, LNG can be stored safely in suitably designed above-ground tanks surrounded by earthen dikes in much the same manner as gasoline.

Jan 1, 1962

By James Paone

Land utilized by the mining industry from 1930 through 1971 amounted to 3.65 million acres, or 0.16 percent of the land mass in the United States. Land reclaimed during the same period was 1.46 million acres, or 40 percent of the land utilized. This report includes data on land use for wastes from underground and surface mining, for wastes from mill operations, and on subsidence. Data on land use and reclamation were obtained from operating companies, mining organizations, appropriate State agencies, and others concerned with such activities. The 10 leading States in land used for mining in 1971 were, in decreasing order, Kentucky, Pennsylvania, Arizona, Ohio, California, Florida, West Virginia, Illinois, Minnesota, and Indiana. Mineral commodities accounting for a major portion of land use are, in decreasing order, bituminous coal, sand and gravel, stone, copper, phosphate rock, iron ore, and clay; for coal, these commodities are produced principally by surface mining operations. Reclamation over the 42-year period was largely on lands utilized for surface mining of bituminous coal. New surface mining methods, particularly for coal, incorporate some form of land restoration.

Jan 1, 1974

By S. J. Page, P. Bolsaitls, W. E. Wallace, C. A. Hill, M. J. Keane

"Boiling respirable quartz dust in water for 10 to 40 minutes decreases the cytotoxicity for both erythrocyte hemolytic potential and pulmonary macrophage release of lactate dehydrogenase in vitro. The potential is reduced to near zero in the boiling concentration range of 1 to 10 mg quartz per ml water in boiling times of 20 to 40 minutes. Below this range the detoxification occurs over a longer boiling time. Above this range the hemolytic potential remaining after 40 minutes of boiling approaches native quartz potential with increasing concentration up to 30 mg quartz per ml water. Replacing the media with fresh at the midpoint of boiling results in full detoxification through 20 mg per ml. Pre—boiling the medium with quartz or silica gel reduces the effect of subsequently boiling test samples. Detoxification persists after mild drying at 110 C for 8 hours, and persists after three days of resuspension in water at room temperature. Additional data on persistence of the effect, on the use of acidic and basic media treatment, and on surface analyses are presented, with a discussion of a working hypothesis and research needs.IntroductionResearch underway to determine interactions of quarts and other mineral dust surfaces with pulmonary fluids and alveolar macrophages in culture led to the observation that when dusts were autoclaved in aqueous suspension, their cytotoxic effects on macrophages wore suppressed, in some cases fully and even after several days incubation with the cells. This finding was in direct contradiction to earlier results from both short term macrophage lysosaal enzyme release assays, as well as longer term cytotoxicity assays from macrophages in culture; in those studies, dusts were steam autoclaved at 121 121 ºC with no liquid water but with steam present. (1,2) However detoxification under boiling conditions has been reported in other research.(3). It was decided to use the hemolysis assay to further investigate these findings, because of its sensitivity, simplicity and cost."

Jan 1, 1988

By M. F. Dunn

The objective of this work was to define jet fan performance in d variety of large cross-section underground mine applications and to develop guidelines for thin performance in open airways, dead headings, and multiple face areas. Measurements include common ventilation instruments, continuous recording remote electronic anemometers to measure air velocity, and sulfur hexaflouride tracer gas with chromatograph analysis to determine dilution rates and air recirculation. For open airways the following were determined: Large jet fans are leas efficient in smaller airways, but quite effective in larger open airways for achieving both uniformity end greater air entrainment, when inclined about 10° or elevated. For dead headings the following were determined: The jet fan must be placed against the rib of the heeding closest to the incoming airstream from the crosscut or recirculation will increase. The fan should be placed at the pillar corner to increase airflow. As the fan is moved closer inby, recirculation increases. Larger fans promote recirculation. Inclining fans about 12° improves airflow in large headings. For face areas the following were found: For panels having uncontrolled airflow, the fan should be placed in the incoming airflow, about one pillar inby, and directed diagonally across the faces. For panels having narrower rooms and controlled airflow, the fan should be placed alongside the panel side in the first room so as to direct or intersect the incoming airflow at the next entry or crosscut.

Jan 1, 1983

By M. Townsend, E. L. Petsonk, H. Abrons, E. Daniloff, K. Kinsley

Workers exposed to certain inhaled dusts may show increased levels of nonspecific airways responsiveness (AR). In some studies, cigarette smokers have also been reported to have increased levels of AR. As part of an ongoing study, we compared the results of preshift methacholine inhalation challenge, spirometry, and smoking and occupational histories, in 191 under-ground bituminous coal miners (M) and 215 non-mining control workers· (C) . All M and c were selected to have normal baseline% predicted FEVI (PPFEV). Mining tenure was recorded as years worked underground (YRUG) and at the coal face (YRFC). AR was assessed as the% decrease in FEVI from baseline divided by the dose of methacholine delivered. M reported similar years smoked (YRSM) but fewer pack-years* (PY) than c~ Overall, both increasing YRSM and PY were associated with more AR*. Smoking C* but not M showed increased AR with increasing PY. In smoking and nonsmoking M, baseline AR and PPFEV showed no association with YRUG. The level of AR was inversely related to YRFC*, possibly representing selection away from dustier jobs. AR was inversely correlated with PPFEV*. In this study, AR and baseline PPFEV were not significantly associated with mining tenure, but cigarette smoking was related to both baseline lung function and level of AR. * p < 0.05 (Supported in part by Grant Gll35142, us Bureau of Mines, Generic Mineral Technology Center for Respirable Dust.)

Jan 1, 1989

By David E. Swanson

The U.S. Bureau of Mines undertook a basic investigation of collimated abrasive water-jet behavior because a more complete understanding of the fundamental process may lead to further technical advances. Laboratory experiments used 2-mm water-jet nozzles and new entrainment apparatus to analyze collimated abrasive water jets operating under varied conditions. Maximum water pressure was 69 MPa to permit use of conventional hoses with a burst-to-operating-pressure ratio of 4. Nozzle and induction line pressures, abrasive induction rates, and jet reactive thrust forces were recorded for each operating condition. Average jet velocity and power were determined from component mass flow rates and reactive thrust force measurements. Relative velocity and cross-sectional distribution of abrasive particles were determined using impact analysis techniques. Other jet characteristics were determined photographically. Properties of free water jets, collimated water jets, and collimated air-water jets were determined for comparison.

Jan 1, 1989