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By J. M. Mutmansky, C. Lee

"Measurement of the size and elemental characteristics was performed on airborne coal mine dust samples collected by multi-stage cascade impactors as well as channel samples of the geologic materials. Size distributions were obtained using precise weighing techniques on the impactor substrates. Elemental analysis on the samples was performed by the proton-induced x-ray emission (PIXE) method, a rapid and non-destructive method of multi-element analysis.The various analyses were performed on 9 major and 21 trace elements. The results indicate the importance of intake air and shuttle car movements as sources of dust. The association of coal dust characteristics with channel samples was investigated using the coefficient of proportional similarity as a statistical measure. Results show a strong relationship between major elements and the geologic material being cut but a similar relationship between trace elements and geologic materials is not consistent.1. INTRODUCTIONThe most significant occupational disease in the coal industry is known ·as coal workers' pneumoconiosis (CW'P). While CW'P has existed for centuries, its mechanism of occurrence and association with coal dust has been well understood for only a few decades. In the 1930s, the significance of this disease led state and government officials in the USA to perform extensive epidemiological and environmental studies in the major coalfields. Study of these results plus later studies in the coal producing countries of Europe eventually led to the dust regulations that appear in the Federal Coal Mine Health and Safety Act of 1969.The impacts of the 1969 act were a productivity decline and increased production cost. Many analysts attributed this in large part to difficulties in complying with the new dust standards (Brezovic 1981). However, compliance was met in most continuous miner sections rather quickly. The remaining problem area is that of longwall mining where the procedures and layout of the minin~ system make it difficult to meet the standards."

Jan 1, 1989

By P. Nicholls

Patent records show that the idea that the burning of fuels can be improved by mixing or pretreating them with chemicals 6 dates back to the early years of the last century. By 1845, English and French patents included the specific beneficiations of elimination or reduction of smoke, soot, and clinker; reduction of the ashes, presumably meaning the total weight of refuse from the ashpit; elimination of sulphur fumes; increase in the rate of burning; increase in the time a given charge of fuel would last; and, in most patents, a saving of fuel. The earlier patents specified additions up to 80 pounds or more per ton of fuel, but after 1860 the quantity was rarely more than 4 pounds. There is no record of the extent to which these patents were commercialized, but after 1884 many American patents were assigned to companies specializing in treatment of coal, so it is probable that the products were marketed on a considerable scale at least as early as that date. From 1900 on, many companies marketed proprietary products that were sold under the general name of "fuel savers." Since its establishment in 1910, the Bureau of Mines has continually received inquiries about these products and, at the request of other govern-mental departments, has tested some used in accordance with the instructions of the purveyors; the results were all negative and, within the accuracy of measurements, the products had no effect on the burning.

Jan 1, 1937

By Terry R. Neumann

The Olallie RARE II study area has volcanic cinder deposits with a sow potential for development. No mining claims or prospects are known within the study area, and except for common construction materials such as volcanic cinders and stone, no mineral deposits were identified. An evaluation of the geology indicates that metallic mineral deposits are unlikely to exist. No significant metallic concentrations were reported in samples from the area. The only resources in the study area are about 30 million cu yds (23 million cu m) of cinders in three cones. The cinder deposits in the study area cannot compete economically with enormous deposits of similar material in more accesible areas closer to markets. At the present rate of consumption, resources outside the area are adequate far into the future. The geothermal potential of the study area is being evaluated by the U.S. Geological Survey.

Jan 1, 1983

By Peter J. Clarke

The petroleum industry continued to be the most important mineral activity in Bahrain during 1978-79. Revenues generated by the petroleum sector increased from $378 million' in 1977 to an estimated $419 million in 1978 and approximately $522.5 million in 1979, despite decreasing production over the 2 year period. There were two oilfields that produced revenues for Bahrain, the Awali oilfield, the nation's only onshore producer, and the Abu Sa'fah oilfield, located in the Persian Gulf, north of Bahrain, The Await oilfield has been decreasing output from a high of 27,973,000 barrels in 1970 to 19,000,000 barrels in 1979. Bahrain shared the revenues from the Abu Sa'fah oilfield with Saudi Arabia, as settlement of an ownership dispute. For the first time, in 1978, revenues from the Abu Sa'fah oilfield represented over 50% of the total receipts from the petroleum sector. The years 1978-79 saw the gradual takeover of the Bahrain Petroleum Co. (Bapco), formerly a subsidiary of the California Texas Petroleum Co. (Caltex), by the Government-owned Bahrain National Oil Co. (Banoco). By yearend 1978, Banoco owned 60% of Bapco, and Caltex the remaining 40%. The Government-owned company controlled exploration concessions, managed domestic marketing of petroleum products, and controlled natural gas production and marketing. On December 15, 1979, the Bahrain Government completed full takeover of the Bapco operations. Bapco will continue to own and operate the 250,000-barrel-per-day oil refinery located near Sitrah, as well as handle foreign marketing of petroleum products.

Jan 1, 1981

By G. A. Apell, E. G. Howe, S. W. Hazen

"INTRODUCTION As a small amount of manganese was produced from the Lake Valley mining district of Sierra County, N. Mex., during the First World War, the district was reexamined in March 1941 by John H. East, Jr., an engineer of the Bureau of Mines, as a possible source of manganese for use during the Second World War. Preliminary examination indicated a substantial reserve of 25 percent ore, so it was recommended that an exploratory program of mapping and sampling be undertaken by the Bureau.The program was started in the fall of 1941 and was completed the middle of 1942. The project 3/ was divided into two parts: The first, an underground sampling program, formed the basis for the second, or churn-drilling program. Mapping and sampling of old underground workings were begun in October and finished in November 1941, whereas churn drilling was begun in February and completed in June 1942."

Jun 1, 1947

By A. W. Deurbrouck

This Bureau of Mines report describes the preparation characteristics of the significant coalbeds from which samples could be obtained in Upshur County, W. Va. One of the 14 samples collected was of metallurgical quality as received, 6 could be sufficiently upgraded to provide acceptable products, and 7 could not be upgraded to metallurgical quality because of their high sulfur contents.

Jan 1, 1967

By Charles A. Kumke

In June 1942 , ' the Bureau of Mines selected the Zonia copper mine , near Kirkland , Yavapai County , Arizona , as a property meriting investigation in connection with its search for supplies of strategic minerals for use in the war . The following month , representatives of the War Production . Board conferred with Bureau officials and requested that the property be explored with the object of determining the tonnage and grade of ore that could be brought into production quickly and mined cheaply by open-pit methods . The work wa's designed to verify information submitted by the owners in support of an application for a Government loan. It was essential that the investigations be completed promptly , so that operations might be planned and copper produced for war needs . The investigations called for surface trenching , diamond drilling , and check sampling of underground workings . Unable to purchase equipment for trenching without considerable delay , the Bureau saved time by borrowing most of the necessary items from the Golden Queen mine of the Gold Fields Development Co. at Mohave , Calif. This company , whose engineers had sampled some of the old trenches , had a tentative agreement with the owners to operate and manage the Zonia mine in event the loan was granted . Additional equipment was borrowed from two Governmental agencies . The exploratory work , completed in 16 weeks , was carried on 7 days a week .

Mar 1, 1947

By James J. Dowd

The investigation to evaluate the reserves of coking coal is being made by the Bureau of Mines in three parts: (1) To estimate known measured and indicated recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coal and coal blends not now widely used for metallurgical coke making. This is the tenth of a series of reports giving the results of studies by counties under part (1) of the investigation. (See appendix.) This report covers Knott County, Ky., which comprises parts of the Salyersville, Prestonsburg, Troublesome, Hindman, Pikeville, Cornettsville, and Whitesburg quadrangles. (See fig. 1.) A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds up to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick. These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and category, mined-out areas, areas excluded from the estimate but which may contain reserves based only on geologic inference, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1952

By S. H. Ash

THE MAGNITUDE of the drainage problem of the anthracite industry in Pennsylvania's Western Middle field is realized when it is known that in 1951 nine pumping plants in this field pumped nearly 36 billion gallons of water to the surface. This is almost 68,000 gallons per minute pumped against an average hydrostatic head of 350 feet for that year alone. In 1948 over 20,000 gallons per minute was pumped by relay pumps against an average hydrostatic head of 265 feet. In addition to the water pumped to the surface, it is estimated that 15,000 gallons per minute overflows to the surface from underground pools in idle mines. The volume (second-feet) of water pumped and overflow water is almost 1;z times the, average mean flow of the Schuylkill River at Pottsville for the 8-year period 1944--51 (7, 13).4 Mahanov and Shamokin Creeks drain an area of 99 square miles in the Western Middle field, and all surface drainage in this area must traverse some part, of the coal measures before entering these streams. On the basis of 46.03 inches of rainfall (the weighted average of 6 recording stations for 1948), the runoff from the drainage area during that period was 51 billion gallons, approximately 1 times the volume of water pumped by all mine-pumping plants in the Western Middle field. In other words, because of the pervious strata overlying the mine workings, approximately two-thirds of the total runoff in the drainage, area becomes mine water tributary to the pumping plants.

Jan 1, 1953

To be able to continuously monitor the noise to which underground workers are exposed as a better way to help prevent hearing damage. The Approach: The Bureau of Mines has developed a Time-Resolved Audio Dosimeter which can be worn by miners to record noise level every 30 seconds and store It in a miniature solid state memory. Figure 1 is a photo of the dosimeter. [ ] How It Works: Acoustical noise is picked up by a micro-phone and fed to a sound level meter which produces a d-c voltage proportional to the A-weighted sound pressure level. (As specified by federal regulations, the A-weighted sound pres-sure level approximates the response of the ear by discounting the higher and lower frequency components of the noise.) This d-c voltage controls an oscillator which, together with related circuitry, produces a pulse train having a frequency that's proportional to the noise level.

Jan 1, 1975

By T. M. Barczak

One of the primary goals of Bureau of Mines research is to reduce the cost of coal mining by improving the efficiency of longwall supports. One method of achieving this goal is the optimization of stress distribution within the support structure, resulting in a lower overall weight, more fully stressed shield. However, before stress optimization can be initiated, load conditions must be defined that cause maximum stress in the various support components. A finite-element model of a longwall shield was used to identify these critical load conditions. These load conditions were then evaluated in the Bureau's mine roof simulator (MRS) by instrumentation of a longwall shield and measurement of strains in each of the shield components. The critical (canopy-base contact) load conditions were identified that can cause structural failure at less than rated shield (hydraulic yield) capacity. Comparisons were made between full-contact and partial-contact load conditions. Other parameters investigated included the stiffness of the contact material, changes in shield geometry, rate of load application, and effects of horizontal constraint. Conclusions were drawn regarding the structural integrity of the major shield components and potential for stress optimization.

Jan 1, 1987

By Frank E. Cash

The compensation-insurance rates for quarrying in North Carolina are 11 times higher than for the State?s major industry, textiles. Some operators are willing to accept this as representing the ratio of existing hazards. This was not true of the management of the Southern Aggregates Corporation, and in 1935 it tools definite steps to correct the idea of its local officials and employees that loss of life and limb in quarries is inevitable. ACKNOWLEDGMENTS The authors acknowledge gratefully the assistance and information concerning these operations furnished by H. M. Shaw, safety director (also secretary and treasurer), Southern Aggregates Corporation, Raleigh, N. C.; by the following superintendents: J. H. Rodgers, Blair Quarry, Blair, S. C.; J. D. Lane, Greystone and Rolesville Quarries, Henderson, N. C. ; J. H. Arthur, Guilquarry, Stokesdale, N. C.; J. H. Watkins, Rockton Quarry, Wendell, N. C.; P. A. Wellenborne, Reidsville Quarry, Reidsville, N. C.; and J. L. Kirchin, Woodleaf Quarry, Woodleaf, N. C.; by the various foremen at the plants, and by Murry Id. Grier, safety engineer, North Carolina Department of Labor, Asheville, N. C.

Jan 1, 1940

By Edmond Chin

The land mass of the Asia and Pacific region comprises 11 million square miles or about 15% of the total Earth's land area. The bulk of the region is contained on the Asian continental land mass. Australia, the world's largest island or the world's smallest continent, alone is almost as large as the continental United States. The islands of New Zealand, New Guinea, Borneo, Sumatra, and Honshu are among the largest in the world. Collectively, they constitute a land area of 1.1 million square miles or an area about one-fourth the size of the United States. The countries in the Asia and Pacific region represent some of the most vibrant economies in the world. Japan is undisputed as one of the world's leaders in manufacturing and commerce. Hong Kong and Singapore are significant both as entrepôt and banking centers. The economies of Australia, the Republic of Korea, and Taiwan compare favorably to the level of the industrialized countries in western Europe. Indonesia, Malaysia, the Philippines, and Thailand have maintained strong economic growth during the past two decades. All these countries in the Asia and Pacific region collectively constitute a significant bloc as to raw materials production and consumption, as to manufacturing, and as to world trade.

Jan 1, 1992

By G. P. Houston

This is the final, report submitted for the Contract No. H0220002 with the U. S. Bureau of Mines for the design and development of a Permissible Automatic Data Acquisition System (PADAS) to measure and record roof stresses in underground mines Basically the PADAS is a portable, battery powered, 24-channel data acquisition system designed for safe unattended operation of up to 30 days duration in explosive environments. The unit will accommodate twenty-four pressure transducers or eight borehole deformation gages (or any combination) at distances up to 300 feet from the PADAS to measure pressures up to 10, 000 psig. All 24 channels as a selected group are scanned sequentially at one of several selectable rates.

Jan 1, 1973

By James D. Eklund

Towards the goal of improving safety, economy and efficiency of scaling in underground metal/nonmetal mines, Battelle developed a combination prying/hammering scaling tool. A prototype was subjected to limited testing 1) to verify its operational functions and 2) to assess its potential capability in future underground testing.

Jan 1, 1983

By Albert L. Toenges, Theodore R. Jolley

"INTRODUCTION The construction of frame houses (fig. 1) in recent years instead of the conventional sod hut (igloo) (fig. 2) by the Eskimos in the villages along the Arctic Ocean has increased the demand for fuel in these villages. The frame houses, which are not insulated against extreme cold and are difficult to heat, are equipped with Goal stoves. The well-insulated sod huts were heated comfortably with whale-oil stoves. In some years whaling is Door, consequently there is a demand for solid fuel.The Eskimo villages usually are on the sand spits at the mouths of rivers and points of land near the best fishing and hunting grounds. These narrow necks of land usually are sand bars that are not underlain with coal, and coal must be transported to the villages. Lack of development of coal deposits in the Arctic has made it necessary to import coal from the States, generally from 'Washington, to supply these villages. This coal is imported by boat and is received once a year. Its cost is, high, and development of coal deposits in the Arctic to supply these native villages should result in a considerable saving to the Government-operated schools and hospitals as well as to the natives.Early traders attempted to establish coaling stations in the Arctic, and the Eskimos generally know where the coal deposits are situated. A. reconnaissance of a number of deposits in the Arctic was made in the summer of 1946 by engineers of the Coal Division, Fuels and Explosives Branch, Bureau of Mines, and this report describes the areas investigated and suggests plans for the development of some of these deposits."

Dec 1, 1947

By Joseph J. Wallace

1. The Pittsburgh is the most important bed in Washington County from the standpoint of present production and recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 4,181 million short tons as of January 1, 1954. Of this total, 4,132 million short tons is in beds 28 inches and more thick. Areas in some beds were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1955

The lignite deposits of the United States represent a huge potential source of fuel for power generation. It has been estimated that lignite constitutes about 24 percent of the remaining National reserves of solid fuel on a tonnage basis and about 15 percent of the reserves on a B.t.u. basis. (See sec. 3, part 1.) The major portion of these reserves is in North Dakota. Lignite has been used locally for domestic heating since the first settlers burned it at forts and fur-trading posts as early as 1855. Some of the first studies of the use of lignite in steam boilers were conducted by the Federal Bureau of Mines from 1910 to 1920 (15, 19) 1/ However, the commercial utilization of lignite as fuel for producing power developed slowly. Not until about 1925 was any really successful lignite industrial fuel-blaming equipment developed. Since then the commercial use of lignite as a fuel for producing power has been increasing steadily.

Jan 1, 1954

By Nicholas G. Theofilos

The only mining activity in Belize during 1976 involved the production of construction aggregates, which were used domestically. A comprehensive ordinance regulating mineral prospecting and mining was proposed during the year. Under the ordinance, which would supersede all grants and titles, ownership and control of all minerals except petroleum would be vested in the Government. Exxon Corp. entered into an agreement with three oil companies to achieve a majority interest in nine oil prospecting leases covering 1 million acres, mostly offshore Belize. The agreement was with Weatherford International Inc. which had 30% interest in the leases, Ajax Petroleum Co. with 40% interest, and Canadian Superior Oil Ltd, with 24% interest. A new entity, Esso Ventures Inc., was established to be responsible for conducting extensive geophysical operations and drilling an exploratory well offshore Belize.

Jan 1, 1980

By Ben E. Lindsly

The recovery or partial recovery of the oil remaining in oil sands after the usual methods of production have become unprofitable is perhaps the greatest problem in the petroleum industry today. The amount of this oil remaining in the sand is variously estimated by those familiar with the subject to be 25 to 90 per cent of the original content.2 Lewis3 states, "The estimate of 80 to 90 per cent of the oil left underground does not seem incredible."

Jan 1, 1926