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By James H. Aase

[This study provides data on the physical and hydrological makeup of the ,t hakes waterway system and forecasts quantities, traffic patterns, and ping cost of prospective bulk mineral commerce projected to be transported it. Factors affecting the shipping cost of iron ore, bituminous coal, imestone were quantified and integrated into a computer program that can d to estimate costs under varying sets of conditions. Combined ship of iron ore, bituminous coal, and limestone in 1995 were estimated at million tons. The cost of operating the U.S. vessel fleet for trans-ng an indicated 80 percent of this traffic tonnage was projected to be $163. 5 million.]

Jan 1, 1970

By A. C. Fieldner

In 1927 the Carbonization Committee of the American Gas Association proposed cooperation with the Bureau of Mines in the development of suitable methods for determining the carbonizing properties of American coals. It was further proposed to apply these methods in the testing of representative coals and to make the information obtained available to the public through Government publications. A cooperative agreement was signed whereby the Gas Association contributed part of the funds necessary for beginning the project and appointed a committee to consult and advise the Bureau in the work. The Advisory Committee has been reappointed each year, and the Bureau has had the benefit of its advice. The composition and carbonizing properties of 33 coals previously tested have been given in technical papers of the Bureau of Mines and in short reports published for the most part in the Proceedings of the American Gas Association. A complete list of publications on the work previous to 1937 is appended to this report. The present report gives the composition and carbonizing properties of seven additional coals from West Virginia. The data include results of blending tests in which Beckley led low-volatile coal was used with all the high-volatile coals except the Alma coal, with which Pocahontas No. 4 coal was used.

Jan 1, 1938

By M. R. Geer, H. F. Yancey

"INTRODUCTION Throughout the history of coal washing, the jig has been one of the most important coal-cleaning appliances. In 1935 34.7 percent of the 45,361,021 tons of clean coal produced was the product of jigging. 4/ Previous to 1928, most of the jigs used in the United States were of the piston type, with which sufficient mobility to allow stratification in bed is imparted by the reciprocating up-and-down movement of a piston in the water compartment adjacent to the screen compartment. In 1928, the Baum type of jig was introduces in this country and has since come into wide spread use. In this type, water pulsations are imparted by application and release of compressed air to the water compartment. All prior studies of the mechanism of seperating cleared coal from impurity by piston-type jigs. 5/ The same laws of settling, of course, apply to both types, piston or Baum, but the character of the separation with the Baum type may be modified more easily because of the flexibility with which air may be handled, as distinguished from the fixed action of eccentrics commonly used in piston jigs. Since no detailed studies are available to show the performance, that is, the character of the separation between coal and impurity, of the Baum type the Bureau of Mines undertook the investigation recorded in this report."

Jan 1, 1938

1. Domestic Production and Use: In 1982, 13 companies operated 30 primary aluminum reduction plants, with 3 firms accounting for 55% of production. Washington, Oregon, and Montana accounted for 34% of the production; Texas, Louisiana, Missouri, and Arkansas 18%; Tennessee, Alabama, South Carolina, and North Carolina 14%; other central and eastern States 34%. Based on published producer prices, output of primary metal in 1982 was valued at over $5.5 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Packaging accounted for an estimated 39% of domestic consumption in 1982, transportation 20%, building 14%, electrical 8%, consumer durables 8%, and other uses 11%.

Jan 1, 1983

By R. G. Warncke, J. H. East, D. Harrington

The mining industry of the United States has long been severely criti- cized because of its high rate of accident occurrence, not only as compared with other industries of the United States but also with the mining industries of other countries, particularly Europe. Statistics, often not strictly com- parable, indicate that the accident-frequency rate in all mining is currently about three times and the accident-severity rate is about seven times as great as the average for general industrial work in the United States. These fig- ures are by no means comforting to humanitarian mining men, irrespective of their status in the industry, and they constitute a challenge that certainly cannot continue to be ignored much longer. The picture becomes much darker when the above statistics are augmented with data indicating that on an exposure basis our mines (more particularly our coal mines) have accident rates two, three, or even more times as great as more or less similar mines in Europe, particularly England, Wales, Belgium, France, and Germany. The sting is alleviated to some extent by the knowledge that our coal mines produce about 4 to 5 times as much coal per man day as is produced in at least some European mines. However, all of these foreign acci- dent statistics should be analyzed carefully before we become very much con- cerned about them, because they are not strictly comparable, for several reasons, not the least of which is the fact that foreign methods of compiling or recording accident statistics often differ materially from ours. Moreover, foreign mining and other conditions are definitely dissimilar to ours in many phases, and numerous other factors affect the comparability of foreign mine- accident statistics with those of the United States. Unquestionably, it should also be taken into consideration that the accident rate of the 140,000,000 or more constituting the populace of the United States as a whole is much higher than that of any other major country in the world and is two, three, or more times the rate of the European countries that have more favor- able mine-accident rates than those of the United States (table 1). Moreover, it is significant that the mine-accident-severity rate of British mines is about six times the average accident-severity rate of the major industries of the British Isles, or but little more favorable than the comparable figures in the United States; namely, that mining has an accident severity rate about seven times the average of about 30 of the major industries of this country.

Apr 1, 1949

By R. L. Levens

Researchers at the U. S. Bureau of Mines conducted investigations to evaluate the potential for ground water contamination by mine waste used as backfill. Samples of cemented waste backfill and water discharging from drillholes and seeps were collected to use in chemical analyses and laboratory tests to determine the physical and chemical factors that control release of heavy metals to ground water. Greater water retention by cemented backfill (as compared to uncemented sandfill) reduces the surface area exposed to oxidation, which in turn reduces the amount of acid produced. The acid is neutralized by the cement and minerals contained in the backfill. The grain-size distribution of tailings used for backfill affects the structural integrity of cemented backfill under attack by acidic water; breakdown of the backfill structure releases neutralizing materials faster. Backfilled stopes in rock with low hydraulic conductivities will constitute preferential flow paths after mine flooding; however, the rate of flow through backfill will be much slower than when the stope is partially saturated during mine operation. Considering all factors, acid generation and release of metal ions from cemented backfill should be less than in uncemented sandfill.

Jan 1, 2010

Capture airborne respirable dust generated by an auger-type continuous mining machine to reduce workers' dust exposure. Approach Install a water-powered scrubber system, operating at 1,400 psi, on the sides of the conveyor. The scrubber draws the dusty air from the face area and discharges cleaned air into the face return. How It Works Auger-type continuous miners pose unique ventilation and dust control problems. To protect face workers from the dust, the end of the brattice is usually maintained close to the face to increase ventilation effectiveness. However, it is taken down as the machine cuts toward the exhaust side to allow the machine to complete its cut. Often, the brattice is not reinstalled in a position to most effectively control

Jan 1, 1989

By Fredrick L. Johnson

Tungsten is the principal mineral commodity in the Laurel-McGee RARE II area; copper and molybdenum would be recovered as by-products with the tungsten. Indicated and inferred tungsten marginal reserves at the Hard Point Mine (fig. l, no. 10) are 16,000 tons (14,000 t) averaging 1.0 percent tungsten trioxide (W03). The mine is outside the RARE II area, but the geologic structure that it is on extends into the area. Indicated subeconomic zinc, silver, copper, and lead resources at the Lucky Strike Prospect (fig. 1, no. 7) are nearly 6,200 tons (5,600 t) averaging 5.45 percent zinc, 0.5 oz silver per ton (19 g/t), 0.40 percent copper, and 0.32 percent lead. Although tungsten has been produced at the Tiptop Mine (fig. 1, no. 12), resources were not calculated because of the spotty nature of the tungsten mineralization. Additional exploration at the Tiptop and Hard Point Mines could reveal significant resources. The potential for tungsten resources at the Payday Prospect, Tungsten Prospect, and Morhardt Mine is also high. The Pine Creek Mine custom mill, located about 35 mi (56 km) southeast, could process tungsten concentrates from the area. Tungsten production has been recorded from three properties, the Hard Point, Morhardt, ant Tiptop Mines. Output was about 405,000 lb (184,000 kg) of W03, nearly all from the Hard Point.

Jan 1, 1983

By Sheridan J. Rodgers

Toxic fumes generated during shot firing were measured in a phosphate rock mine and a copper mine. Fumes generated during firing of explosives in the Bureau of Mines 1350 ft3 test chamber were measured also. The release of fumes from water gels, ammonium-nitrate oil mixtures and nitroglycerin based explosives was studied. Direct reading instruments were used to monitor the fume concentrations. The amount of CO produced per unit weight of nitroglycerin explosives (0.41 ft3/200 grams) was higher than that produced by ammoniumnitrate-oil mixtures (0.24 ft3/200 grams) and water gels (0.16 ft3/200 grams). The amount of NOx produced by nitroglycerin based explosives was also higher than the amount produced by water gels or ammonium nitrate-oil mixtures.

Jan 1, 1976

By J. Ronald Lawter

The purpose of the work described in this report was to measure the effects of diesel engine emissions on the air quality of work areas in a coal mine. Concentration measurements of a number of diesel related air contaminants were made at the Martin County Coal Corporation Mine in Inez, Kentucky. Compounds measured included carbon dioxide, carbon monoxide, formaldehyde, nitric oxide, and nitrogen dioxide. In addition, concentrations of the two classes of odorous compound;, aromatic hydrocarbons, and oxygenates were obtained along, with aldehyde concentrations. Surveys were made of the mine by odor analysts to determine the perceived intensity of diesel-produced odors. It was found that the concentrations of the measured species were well below their Threshold Limit Values. Odor intensity levels in the moderate to strong range were observed in the mine.

Jan 1, 1977

By Albert L. Toenges

This paper is the third of a series4/ that describes some methods and practices of mining coal mechanically where operations are conducted on more than one shift. The mining of coal by means of mechanical devices has emphasized the need for continued study of the relationship, of these devices to existing physical conditions and to planning of the operations for increased safety and economy. The purpose of this investigation is to stud the operations of different types of mechanization used in mines under various systems of mining and physical conditions to reach conclusions as to the safest and most economical methods and practices of mining. Physical conditions very in different and in the same mining districts and determine, together with economical conditions, the systems of mining and the types of mechanical loading equipment used. The information presented in this paper

Jan 1, 1941

By Frank E. Cash

The information in this report covers the accident experience of the pebble-phosphate industry of Florida for 1935 and 1936, as well as the 5 years 1930-34, inclusive, statistics of which were published in Information Circular 69174/. The compilation and publication of such accident experience statistics enable the pebble-phosphate industry, as well as other industries, to consider relative hazards and to compare experience and thereby promote accident prevention.

Jan 1, 1937

A maximum acceptable level of 2 mg/m3 of respirable coal mine dust in active mine workings was established, effective January 1, 1973, under the Federal Coal Mine Health and Safety Act of 1969. It is generally agreed that, as a result, coal mines in the United States are significantly less dusty than they were a decade ago. For example, operators of underground mining machines were exposed to between 3.9 and 6.5 mg/m3 of respirable coal mine dust during 1968-69; now they are exposed to between 1.3 and 1.8 mg/m3. Also, the incidence of underground sections cited for exceeding acceptable levels of respirable coal mine dust decreased during 1976-78, and the vast majority of all working sections are now in compliance. This improvement is very substantial by world standards. It must be regarded as a creditable accomplishment by the coal mine operators, federal agencies, and mine workers involved. Most of the improvement has been brought about by the use of existing technology to control, suppress, and collect respirable coal mine dust. Research and development by the Bureau of Mines has contributed significantly to the accomplishment by improving the methods for sampling, control, suppression, and collection.

Jan 1, 1980

By Harold L. Rhodes

The Bureau of Mines has developed a method for determining the H2S content in natural gas samples. A gas chromatograph with a flame photometric detector was used to analyze samples with H2S concentrations ranging from 5,000 ppm to a minimum detectable limit of 0.01 ppm. A mass spectrometer was used to analyze samples containing H2S in amounts greater than 5,000 ppm. Methods are presented for preparing containers for H2S samples and for preparing standards using partial pressure and weighed standard methods, Sample collection techniques are discussed, as are analytical results which illustrate the loss of H2S while in the sample container and provide a basis for evaluating containers used for sampling and standard preparation.

Jan 1, 1979

By T. E. Gray, A. W. Deurbrouck

This report describes the preparation characteristics of significant coalbeds in Kanawha County , W. Va . It is one in a series of Federal Bureau of Mines reports planned to determine coals suitable for producing metallurgical coke , either as mined or after beneficiation . Almost 9.4 million tons of coal was produced in Kanawha County , W. Va . , in 1959 , of which about 67 percent was cleaned mechanically in 10 cleaning plants . It has been estimated that more than 5,505 million tons remain in the county . Samples were collected from Pittsburgh , Stockton - Lewiston , Winifrede , Cedar Grove , Peerless , Upper Kittanning , Coalburg , Powellton , Eagle A , No. 2 Gas , and the Lower Kittanning beds . These beds were selected by the Bureau based on current production rates and estimated minable reserves . Float - and - sink tests of the samples collected from Eagle A , Peerless , Cedar Grove , Winifrede , and No. 2 Gas beds show that these coals at one location each are suitable for metallurgical use without washing . Lower Kittanning bed at four locations ; Pittsburgh , Stockton - Lewiston , and No. 2 Gas beds at two locations each ; and Coalburg , Powellton , Winifrede , Peerless , Upper Kittanning , and Cedar Grove beds at one location each can be upgraded to metallurgical quality by mechanical cleaning . Crushing the samples to 3/ 8- inch top size increased yields substantially at 1.30 specific gravity of Pittsburgh ( 17.5 percentage points ) and Upper Kittanning ( 13.0 percentage points ) beds and increased yield for the other beds sampled to a lesser amount . At this specific gravity , finer crushing caused In the 1.58 specific gravity float a general decrease in ash and sulfur . fractions of the other samples tested , most of the yields , and ash and sulfur contents , were lowered slightly by finer crushing .

Jan 1, 1963

By G. L. Anderson

The critical importance of wire rope integrity to the mining industry has led to the creation of standards for the retirement of wire rope as well as to the development of electromagnetic devices and procedures that would allow wire ropes to be tested against these standards without destroying them, The U.S. Bureau of Mines (USBM) conducted research to evaluate these devices by measuring loss of metallic cross-sectional area and the number of wire breaks, or local faults. The intent was to define the extent to which the technique can identify degradation within the rope, e.g., broken wires, corrosion, and wear. Experimental results showed that instrument sensitivity depended on a number of factors, including rope diameter, placement of sensors, location and characteristics of flaws, rope speed, and tension on the rope. The experiments also demonstrated the importance of having an elongated recorder trace and a properly trained and experienced operator to interpret overall results. A design of a rope and test procedures for use in laboratory evaluation of instruments have been recommended by the American Society for Testing and Materials Committee E07.07.10, Wire Rope Applications. The USBM is working through this committee to develop standards for an electro-magnetic method of wire rope inspection.

Jan 1, 2010

By D. K. Denton, J. M. Girard, D. F. Scott, T. J. Williams

Personnel from the Spokane Research Laboratory, National Institute for Occupational Safety and Health, examined an underground pillar at the Homestake Mine, Lead, SD. Investigations involved strain relief and seismic tomography studies in the mine, and ultrasonic velocity measurements on pillar core in the laboratory. Measured octahedral normal stress was 37 MPa (5,366 psi); seismic P-wave velocities averaged 5.2 km/s (17,060 ft/s); and ultrasonic velocities at a pressure of 39.6 MPa (5,750 psi) averaged 6.3 km/s (20,669 ft/s). The difference between in-mine and laboratory velocities is attributed to the attenuation of seismic energy by mine fractures larger and more numerous than those in the samples of core measured in the laboratory. Using these results, researchers hypothesize that pillar rocks have the ability to withstand stress an order of magnitude greater than they currently sustain.

By H. R. Pierce

A gas well has a certain definite capacity to deliver gas from the gas sand through the producing string of pipe. This capacity depends upon the pressures in the sand; that is, a well will deliver gas at a rate of flow which is determined by the formation or "shut-inn pressure in the sand and the back pressure at the face of the sand in the well. The three factors, rate of flow, formation or "shut-in" pressure, and the back pressure, for a given well, can be written into a fundamental relation which is strictly applicable only to that well. This relation can be used to determine the capacity of the well to deliver gas from any formation pressure against any back pressure held at the f ace of the sand in the well. Studies have been made of the deliveries of 400 gas wells operating under different conditions of pressure, Most of the wells which have been studied are in Osage County, Okla.; however, several representative studies have been made on wells in southern Louisiana, southern Texas, the Texas Panhandle, and West Virginia.

Jan 1, 1929

BIBLIOGRAPHY Allen, C.A, Analyses of Utah Coals, United States Bureau of Mines Technical Paper 345, 1925, pp. 90. Allen, J.E. and E.M. Baldwin, Geology and Coal Resources of the Coos Bay Quadrangle, Oregon, Oregon Department of Geology and Mineral Industries Bulletin 27, 1944, pp. 160. "Aluminum Boom Raises Productivity", Coal Age, Vol. 82, No.6, June, 1977, pp. 103.

Jan 1, 1978

By Robert J. Timko

In early June 1986, an underground fire of unknown origin erupted in one of several entries of a coal mine located in southwestern Colorado. For a time, mine personnel aggressively fought the fire. However, control of the fire was later lost. To prevent further damage and reduce the possibility of an explosion, all portals and shafts to the mine were sealed. The mine operator requested the U.S. Bureau of Mines' assistance in obtaining and analyzing mine fire gases taken from sampling ports placed through the mine seals, as well as down boreholes drilled after the fire. This report recounts activities within the first 2 years of the mine being sealed. It includes a description of gases analyzed and mine atmosphere status equations generated from the analyzed gases. The gases were analyzed by chromatography and included standard atmospheric gases as well as higher hydrocarbons that are found in postfire atmospheres. Nine equations were used to evaluate what was occurring within the sealed mine. Following a description of the rationale behind each equation, the 2-year trend is briefly analyzed.

Jan 1, 2010