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To allow routine measuring of the exposure of underground workers to N02 from diesel engines and residual gases from blasting. The Approach: A miniature sampler absorbs NO2 which can be measured using a simple method adaptable to both multiple automatic analyses or individual on-site analysis. How It Works: The NO2 sampler is encased in a plastic tube approximately half the length of an ordinary ball point pen and clipped to an underground worker's hard hat. Removal of the end cap activates the personal sampler. Air from the working place enters the open end and diffuses at a controlled rate down the tube interior. The diffusion rate is dependent on tube dimensions (ratio of cross-sectional area to length). The closed end of the tube contains stainless steel mesh which is coated with triethanolamine (TEA) for absorbtion of all NO2 reaching it. Other oxides of nitrogen are not absorbed. The amount

Jan 1, 1975

By R. M. Becker

THIS IS a progress report on a study of the application of statistical practice to mine and mineral sampling undertaken by the Federal Bureau of Mines to provide sound theoretical and practical data for use of the mineral engineering professions. One of the problems in mine sampling is determining the reliability of the results. For certain types of sampling data (random data) the reliability of the results can be stated mathematically. For other types of data there is no known means of quantitatively expressing reliability. In applying measures of reliability to a set of random data, some knowledge or assumption of the characteristics of the particular data is necessary. In many fields these characteristics are well known. However, in mining, where the data are in assays, these characteristics are not well known.

Jan 1, 1961

By L. Nahai

Iran's petroleum industry is nearly 50 years old and the oldest in the Near East. According to published figures, Iran ranks third in production and reserves in the Near East. These reserves (including probable reserves) are estimated at 35 billion barrels and constitute about 11 percent of the world's total. Iran is the sixth largest producer of crude petroleum in the world. The 1961 output of more than 430 million barrels was 5 percent of total world output for the year. In the same year, Iran ranked fourth among world petroleum exporters, providing 8.4 percent of total world exports.

Jan 1, 1963

By B. W. Gandrud

[This report presents the data of one of a series of investigations of the washability of Alabama coals as indicated by float-and-sink tests mode by the Bureau of Fines at the Southern Experiment Station in cooperation with the University of Alabama and Alabama coal producers. The Klandyke mine, operated by the Blocton Mining Co., is about 1 mile eat of Vest Blocton, Bibb County, Ala., floor the southwestern, extremity of the Cahaba coal field. The Bureau of Mines already has published three reports that deal with the, washability of Cahaba coals - one a washability study of the Clark bed at Marvel4/ one on the tabling of fine coal from the Thompson and Woodstock beds5/, and the third a washability study of the Henry Ellen bed at Acmar6/.]

Jan 1, 1939

Combine the MSHA and OSHA versions of the HazCom Helper into one easy-to-use software tool.

Jan 6, 2007

By Erle C. Donaldson

A study of subsurface waste disposal in the United States shows that in eight States a wide variety of industrial wastes are being injected into formations ranging in age from Precambrian to Recent. More than 30 wells ranging in depth from 300 to 12,000 feet are used for waste disposal into subsurface formations which include unconsolidated sand, sandstone, vugular limestone, and fractured gneiss.

Jan 1, 1964

By Erle C. Donaldson

A study of subsurface waste disposal in the United States shows that in eight States a wide variety of industrial wastes are being injected into formations ranging in age from Precambrian to Recent. More than 30 wells ranging in depth from 300 to 12,000 feet are used for waste disposal into subsurface formations which include unconsolidated sand, sandstone, vugular limestone, and fractured gneiss.

Jan 1, 1964

By Albert W. Deurbrouck

The performance characteristics of five hydrocyclone coal washers were evaluated to determine the sharpness and efficiency of separation that might be anticipated in commercial operation. The hydrocyclone overflows contained generally good clean coal products that would require little re-treating to remove misplaced high-gravity material. The underflows, however, contained from 63.6 to 36.7 percent of misplaced low-gravity material, which would require secondary cleaning to provide acceptable clean coal yields.

Jan 1, 1974

By J. S. Miller

This report presents a complete coverage of results from Bureau of Mines preliminary research and the field application of explosive fracturing techniques to prepare oil shale for in situ recovery of shale oil. Small-scale surface tests were conducted to determine the feasibility of using a nitroglycerin-base explosive for creating rock fractures. Prior to underground testing, surface and near-surface tests with liquid explosives showed that explosions in sheetlike layers simulating underground fractures would propagate effectively. Successful surface experiments were conducted using layers of explosive placed between glass plates and explosive-saturated sand confined in small-diameter metal tubes. The tests in glass-plate reservoirs and metal tubes demonstrated that nitroglycerin would detonate and the explosion would propagate in cracks as thin as 1/32 inch and through distances up to 12 feet. In a shallow field test, nitroglycerin was detonated in a vertical crack in limestone and produced extensive fracturing. Explosive fracturing tests were performed in oil shale formations on seven sites near Rock Springs, Wyo. The procedures included (1) displacing and detonating nitroglycerin in natural or hydraulically induced fracture systems; (2) detonating nitroglycerin in wellbore shots; (3) displacing and detonating nitroglycerin in induced fractures followed by wellbore shots using pelletized TNT; and (4) detonating wellbore charges using pelletized TNT. The research on oil shale formations demonstrated that nitroglycerin displaced in a natural or hydraulically induced fracture would detonate, and the explosion would propagate through the explosive-filled fracture. Shooting a pattern of wells in oil shale at 100-foot depth with wellbore charges of pelletized TNT developed a satisfactory interwell fragmented zone. Tests performed on other sites at depths to 385 feet caused fragmentation of rock around the wellbore and provided interwell communication. Fourteen methods used to evaluate the extent and degree of fragmentation in the explosive fractured oil shale are discussed.

Jan 1, 1974

By H. B. Hill

The Salt Flat field, formerly called the Toe -Bruner field, is located northeast of the town of Luling in Caldwell County, Tex. This field, which is a fault structure, approximately parallels and is about 5 miles east of the Old Luling field. The proved area is approximately 1,280 acres, on which 332 producing wells (September, 1930) have been drilled. The majority of the wells are producing from the Edwards limestone at an average total depth of 2,700 feet. A few wells are producing from the Austin chalk or from other formations above the Edwards limestone. The Wilcox formation is exposed, and the fault trace in places is scarcely evident. The strike of the structure is approximately 111. 20 to 45° E. The displacement of the fault is probably 200 to 500 feet. The discovery well was completed in the Austin chalk by the Lutex Oil Co. during April, 1928. In October, 1928, the Sun Oil Co. completed the discovery well in the Edwards pay. This well was an important discovery, as it indicated the potential oil possibilities of the Edwards limestone in echelon fault structures. The discovery led to the development of the third fault field in the Edwards limestone and opened up a large area for future prospecting. The total oil production for the Salt Flat field to and including September, 1930, was 19,833,215 barrels. The most reliable figures available of water production were compiled for a number of leases and wells in the south half of the field. These data show that the water percentage for the average well in this part of the field increased steadily from 30 per cent for January, 1929, to 81 per cent for December, 1929. The estimated daily water production of the entire field for December, 1929, was about 82,000 barrels as compared with a daily oil production of 29,725 barrels; or approximately 2.7 barrels of water were produced with each barrel of oil 14 months after the discovery well was completed in the Edwards pay. Estimates of water production in the (Old) Luling field, which is near the Salt Flat field, place the daily water production at about 150,000 barrels (July, 1929) as compared with a daily oil production of 11,000 barrels. These figures indicate that in the Luling field approximately 14 barrels of water must be lifted for each barrel of oil produced. The Luling field was discovered in August, 1922, and a peak annual production of 10,210,000 barrels was reached during 1924. The production during 1928 was 5,057,000 barrels of oil from an average of 567 producing wells for the year. Although water appeared early in the life of the Luling field, the oil production has been well sustained. Another feature of outstanding interest is the comparatively few producing wells that have been abandoned on account of water during the soven years of operation of this field. Comparison of data between the Luling and Salt Flat fields is of importance because of the nearness of the two fields. The Luling field is a narrow strip or "shoestring" approximately 8 miles long, with a maximum width of 3,400 feet. Production is obtained in the Edwards limestone at an average depth of 2,200 feet on the upthrow side of a fault. Similar conditions of accumulation are found in the Salt Flat field at greater depth to Salt Flat field as outlined (April, 1930) is about 7 miles long? with a maximum width of 2,000 feet. At the time the field work was begun (July, 1929) in the Salt Flat field, drilling operations had been almost completed in the south half of the field, while the north half was still under development. Cross sections and a structure contour map interpret the subsurface conditions in the south half of the field, where the water conditions first became serious.

Jan 1, 1931

By J. Fletcher Smoak

Consumption of abrasive materials in the United States in 1981 was approximately $340 million, of which 37 % was industrial diamond (natural and synthetic), 39% manufactured abrasives, and 24% natural abrasives. Production and shipments of natural abrasives, excluding emery and industrial diamond, decreased in quantity 9% and 7%, respectively, when compared with that of 1980. Emery showed the largest change in output, decreasing 30% in quantity and 20% in value. Production of nonmetallic .manufactured abrasives material plus shipments of metallic abrasives material decreased 5% in quantity but increased 4% in value. Nonmetallic manufactured abrasives consisted of aluminum oxide (fused) and crude silicon carbide produced in the United States and Canada and accounted for 63% of the value of all manufactured abrasives. Metallic abrasives shipments included chilled and annealed iron shot and grit, steel shot and grit, plus cut wire, aluminum, and stainless steel shot and equaled 37 % of the value of all manufactured abrasives.

Jan 1, 1982

By W. H. Tomlinson

This publication presents the basic text for a 20-hour accident-prevention training course developed for supervisors by the Federal Bureau of Mines. During the past 2 years, the course has been used by the Bureau in teaching more than 300 groups of coal-mine supervisors-men whose responsibility is twofold: To manage in production and maintenance phases of coal mining and to guide their men along paths of safety. This is a handbook for teaching teachers. In this handbook will be found references to safety practices followed by companies that consistently have low accident records. These companies credit their outstanding performance to the adoption and faithful observance of accident prevention by supervisors and workers alike on a wholesome, cooperative basis. Teaching safety to workers involves both on-the-job and classroom-type instruction. If such training is to be permanently effective, it must be reinforced consistently on the job by the immediate supervisor of the worker. This publication is intended to provide such a supervisor with the motivation to provide such follow-up and shows how he can accomplish it effectively.

Jan 1, 1962

By A. T. Tye

This paper describing the concentrator practice of the Cananea Consolidated Copper Co. at Cananea, Sonora, Mexico, is one of a series of articles on milling methods and costs being prepared by the U. S. Bureau of Mines. The Cananea concentrator treats 2,400 tons of copper ore per day by preferential flotation, whereby the copper sulphides are floated and the iron pyrite depressed. During the first half of the year 1929 the heads to the concentrator averaged 3.29 per cent of copper, the recovery was 95.74 per cent of the total copper, and the concentrates produced contained 21.44 per cent of copper.

Jan 1, 1930

By C. W. Davis, M. W. Von Bernewitz, S. C. Lind

During the past few years our possible domestic resources of platinum have attracted much attention . On account of the extensive use of platinum during the World War , and the practical elimination of the Russian supply , the price of this metal rose to new high levels , as shown in Table 1 ; and though it since receded to some extent , the price is now nearly six times that of gold .

Jun 1, 1923

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nonmetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By Ren G. Dong, Thomas W. McDowell, John Z. Wu, Chris Warren, Dan E. Welcome, Chun L. Dong

Hand forces are important factors for risk assessment of hand-arm vibration syndrome (HAVS).1 Grip force is one of the most important force components in the operation of powered hand tools. A considerable number of studies on grip force have been reported. It is well known that the grip force applied on a cylindrical handle is not uniformly distributed on each axis across the center of the handle cross-section.2 Therefore, maximum and minimum orientations of grip force exist around the handle. Such orientations have not been clearly identified. In a recently proposed international standard (ISO/CD 15230, 2005),3 it is stated that “the direction of the main gripping force is generally parallel to the z-axis defined in ISO 8727.” 4 This assertion is questionable, and further examinations are required. The objective of this study was to establish a fundamental theory on the distribution of the grip force around cylindrical handles. Methods As shown in Fig. 1, the grip force is defined as a vector composed of normal and shear components (FN & FT) in this study. Fig. 2 shows the hand coordinate system defined in this study, together with the ISO systems.1,4 Based on this novel grip force definition, we derived four fundamental properties and a theorem. More significantly, we formulated a novel hypothesis: similar to Mohr’s circle of stress, the normal and shear components can be represented approximately using an ellipse on the plane of the two force coordinates, as shown in Fig. 3. The maximum and minimum grip normal forces are termed as the first principal grip force (F1) and the second principal grip normal force (F2), respectively. Their corresponding orientations are termed as the first principal grip angle (a1) and the second principal grip angle (a2). A series of experiments were conducted to test this hypothesis. Twelve

Jan 6, 2006

By M. E. Poad, J. K. Whyatt, T. J. Williams

Researchers at the U.S. Bureau of Mimes monitored rock mass response to mining of an experimental underhand longwall stope in Hecla Mining Co.'s Lucky Friday Mine, Mullan, ID. This stope design, the Lucky Friday underhand longwall (LFUL), was proposed as a means of controlling rock bursting while also allowing increased mechanization of mining operations. Instruments were specifically manufactured to monitor three geomechanical factors (backfill performance, ramp stability, and rock mass response) that directly affect the success of stope design. Despite considerable difficulties with instrument installation and survival in the harsh mine environment, especially within the stope fill, sufficient information was collected to suggest that the LFUL method was successful in achieving project goals. This conclusion, in addition to favorable economic and operational evidence, led the mine to adopt the method throughout the mine. Indeed, this study and mining experience suggest that underhand longwall mining could be considered a feasible mining method for rock-burst-prone ground throughout the Coeur d'Alene District. Further Reports of Investigations (RI) in this series present in-depth analyses of the effects of backfill on rock bursting and calibration of a stope numerical model.

Jan 1, 1992

The Bureau has published much data on sulfur (4, 15, 23)3, most of it dealing with national or international aspects of the sulfur industry. Little information, however, is available on sulfur marketing in specific States or areas, Therefore, the Bureau has conducted a survey of the resources, production, consumption, and economic future of the sulfur and sulfuric acid industry in States of the Central and Southern Rocky Mountain area - Wyoming, Colorado, Utah, Arizona, and New Mexico - and in the Northern Plains States - North Dakota, South Dakota, and Nebraska, even though these States do not represent an economic or marketing unit. The purpose of this survey is to review the demand for sulfur and primary sulfur compounds that draws upon the natural resources of the region, to discover opportunities for better use of these resources, and also to analyze and evaluate the patterns of consumption, sources of supply, and other factors that affect the demand for these mineral products. While this survey stresses the economic and marketing phases of the industry, a complementary report (32) emphasizes the resources of sulfur in Wyoming, Colorado, Utah, New Mexico, and Arizona.

Jan 1, 1962

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nomnetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By G. S. Knoke

This report presents the results of a demonstration of the technical, economic, and environmental feasibility of hydraulic borehole mining of shallow oil sands. Borehole mining offers a method for extracting the oil sands with minimal disturbance to environmental quality because (1) no overburden is removed, (2) no waste rock piles are required, (3) the tailings can be backfilled into the borehole cavity, (4) the ground water quality should be undisturbed, (5) a closed-loop water system can be employed so that no surface streams are polluted, and (6) surface subsidence can be minimized by backfilling the mined cavities. This project consisted of two concurrent tasks: mining operations and environmental monitoring. To generate the environmental impact, nearly 1000 tons of oil sands were mined from two boreholes. Water quality and ground subsidence were monitored. No significant changes occurred in the chemical composition of the process water, indicating that the borehole mining process does not dissolve the mined material. The average subsidence in the immediate vicinity of the boreholes was about 1/2 inch, although some points were noted to be slightly elevated. In general, the amount of subsidence increased with time and decreased with distance from the bore-hole. A mining cost analysis was used to project an estimated cost for production mining of about $38 per barrel of oil.

Jan 1, 1980