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By J. L. Stauffer, L. J. Gaydos, L. M. Demers, D. C. Kuhn

"Eicosanoids and cytokines produced by alveolar macrophages (AM) are key mediators of pulmonary inflammation and fibrosis. In order to determine if eicosanoid production and cytokine production are altered in AM obtained from coal miners, we compared production of prostaglandin E2 (PCE2), thromboxane A2 (TXA2), leukotriene B4 (LTB4), interleukin-1 beta (IL-1B ), and tumor necrosis factor alpha (TNfa.) by cultured AM from normal human subjects and coal miners. The recovery of AM from miners' lungs by bronchoalveolar lavage was significantly greater than that from control subjects. Mean eicosanoid and cytokine production by AM from active miners was also increased compared to AM from control subjects, but this increase was not statistically significant. AM from control subjects produced significantly more TXA2 and TNFa. when exposed to lipopolysaccharide than did AM from miners. The cyclooxygenase inhibitor suprofen reduced PGE1 and TXA1 production and TNF0t. release but had no effect on LTB4 production or IL-1B release by miners' AM. The lipoxygenase inhibitor nordihydroguaiaretic acid attenuated TNFa release, as well as that of LTB4, but had no effect on IL-1B release. Inhibition of thromboxane synthase by UK 38,485 also reduced TNFa release by active miners ' AM but had no effect on PGE1, LTB, production, or IL-1 f3 release. The results of these studies suggest that occupational inhalation of coal dust may increase total lung eicosanoid and cytokine levels and reduce the reactivity of AM to bacterial endotoxin. Furthermore, coal dust-induced changes in both eicosanoid and cytokine release may be subject to pharmacological modulation.The alveolar macrophage (AM) is a primary defensive cell in the lung and is one of the first cell types to encounter inhaled mineral dust. The response of the AM to invading foreign material is designed to enhance the defensive capacity of the lung. However, in the case of occupational inhalation of mineral dust particles, this response may be inappropriate, resulting not in the defense of the lung but in chronic inflammation and fibrosis (Rom et al., 1987; Takemura et al., 1989). The reaction of the AM to chronic mineral dust exposure may involve the exaggerated release of paracrine mediators of lung function, including eicosanoids (oxygenated derivatives of arachidonic acid) and peptides, including cytokines and growth factors (Sibille & Reynolds, 1990). Eicosanoids are involved in bronchial and vascular smooth muscle reactivity, vascular permeability, fibroblast growth, and the recruitment of additional immune cells to the alveolar space (Barnard et al., 1992; Elias et al., 1985; Scott et al., 1982). AM-derived cytokines such as interleukin-1 beta (IL-1 B) and tumor necrosis factor alpha (TN Fa) have a variety of biological activities including the regulation of fibroblast growth and proliferation (Becker et al., 1989; Libby et al., 1989; Schmidt et al., 1984). Interestingly, in vitro studies with macrophages suggest that the production of cytokines may be linked to eicosanoid production, in particular that prostaglandin E2 (PGE2) may down-regulate IL-1 f3 and TN Foe production by the AM (Bonta et al., 1989; Kunkel et al., 1986; Monick et al., 1987)."

Dec 1, 1996

By Paul S. Goodman

This report examines the effectiveness of bonus plans in the coal industry. The analysis uses theoretical, literature review and empirical approaches to determine the impact of bonus plans on safety and productivity in underground coal mines. The basic finding is that the modal bonus plan in underground coal mining does not have a major impact on productivity and safety indicators. The design of the plan, or organizational factors, and the process of introducing the plan all contribute to its relative ineffectiveness. Strategies and options for designing effective plans are presented.

Jan 1, 1987

By W. P. Diamond, John C. LaScola, D. M. Hyman

In 1972, the Bureau of Mines developed a direct-method test for measuring the gas content of virgin coal core samples for coal mine health and safety considerations. Since that time, approximately 1,500 coal samples from more than 250 coalbeds in 17 States have been collected for gas content determination. The gas content data, when combined with geologic and engineering studies, can be used as a basis for a preliminary estimate of mine ventilation requirements, and to determine if methane drainage in advance of mining should be considered. The data are also critical in delineating coalbed methane resources and in utilization feasibility studies. This report makes the Bureau's extensive data base of gas content data more readily available to the coal and gas industries. The data are presented in tabular form, alphabetically by coalbed name and by State. The components of the total gas content (lost, desorbed, and residual gas) are given, Location (State and county), sample depth, coalbed or formation name, and coal rank are included for geographic and geologic identification.

Jan 1, 1986

By R. G. Dressler

The design and operation of the Koppers powdered-coal gasifier and its auxiliaries at Louisiana, Mo., are described. This unit was designed to convert 1 ton of coal per hour with oxygen and superheated steam into synthesis gas - primarily carbon monoxide and hydrogen. The first run was made on May 4, 1949. After this, 44 short runs (less than 8 hours each) and 1 long run (lasting 11 days) were made. Total gasification time was 420 hours. The gasifier was not cooled down during the year when these runs were made. After an initial period of test operations and equipment proving, during which 12 runs were made, the effect of numerous variables on gasifier performance was studied. The long run was made primarily to check the equipment in sustained operation. Detailed data from these runs are presented.

Jan 1, 1954

By Jr. Flynn

"The Bureau of Mines receives and answers many requests for information on the qualities and properties of American coals, and also publishes many papers that deal with coal characteristics. Compilations of chemical analyses of coal from specific locations are contained in a series of technical papers,2/ by States, whereas typical analyses of coal seams, by States and counties, are given in data books, volumes 1 to 7,2/ by producing districts, as defined in the Bituminous Coal Act of 1937. Bulletin 446, ""Typical Analyses of Coals of the United States,"" condenses and supplements these data books, which do not apply to the Western States. Other coal properties are described in numerous publications listed in the Bureau of Mines Bibliography of Publications. However, no recent publication lists average B.t.u. values by rank on a Statewide and national scale. Averages have been estimated in the past, and some of them are included in this paper for comparison.The average and the ranges of as-received B.t.u. values of American coals on a Nation-wide basis, as found by the statistical method described in this paper, are given in table 2 and on a State-wide basis in table 3. The following is abstracted from table 2:In deriving average B.t.u. values for coals, the results depend on the type of data available and the methods of calculation. The data, or analyses, may represent any of three types of samples - mine, tipple, or delivered. In mine sampling, a channel cut is made of a vertical face of the coal bed, carefully excluding most of the impurities, and the material retained is the sample. It is readily seen that mine samples are selected samples and do not strictly represent the unmined coal bed, unless the coal contains no major impurities. Mine samples generally represent the best-quality coal that could be produced. In contrast to mine samples, tipple and delivered samples represent coal that actually has been mined, and their analyses may show either lower or higher values than mine samples of the same coal, depending on treatment and preparation after mining.Of the thousands of analyses accumulated by the Bureau of Mines, most are of either tipple or delivered samples and represent the coal after it has been mined. Any average calculated from this aggregate of data will, consequently, reflect coal that has been produced, and not unmined coal in situ.The method of calculating an average from the basic data also will have considerable influence. If there are three seams of coal in a county, the average analysis for the county is not necessarily the arithmetic mean of analyses of the three individual seams. For a probable average of unmined coal, the B.t.u. values of each seam should be weighted in proportion to the unmined reserves of each seam. In similar manner, an average for past pro¬duction should be weighed according to the past production for each seam. Figures for coal reserves are only estimates based upon geologic evidence and its interpretation. Production records are much more accurate than estimated reserves, although detailed production records for individual seams by counties are very few."

Dec 1, 1949

By F. Garcia, J. Cervik

The cross-measure borehole technique has been shown by the Bureau of Mines to be an effective method of controlling methane liberated by fracturing the roof strata in longwall gobs where overburden is less than 750 ft (229 m). Boreholes are drilled into roof strata before mining operations affect the roof strata. Longwall mining fractures the roof strata and releases methane from source beds. Surface exhausters or vacuum pumps are used to draw the gas to the surface through an underground pipeline and vertical exhaust hole. The captured methane is thus prevented from entering the mine's ventilation system. About 71 pct of the methane produced by longwall mining in the Lower Kittanning Coalbed was captured by the cross-measure boreholes. Borehole spacing is an important factor affecting the performance of the technique. Interference tests and measurements of methane flows in return air indicate borehole spacing in the Lower Kittanning Coalbed should be limited to about 200 ft (61 m) except on the first 600 ft (183 m) of the longwall, where spacing should be reduced to about 100 ft (30 m) to capture the large quantities of methane released when the first large roof fall occurs. Comparisons between measured and calculated gas pressure differentials on boreholes indicate borehole length can be reduced from 280 to 140 ft (85 to 43 m), which reduces drilling costs significantly. Additional experimentation is necessary to verify the calculations.

Jan 1, 1985

By George S. Rice, O. P. Hood

The need of protecting mines from the danger of inflow of natural gas from neighboring wells has become more apparent each year since it was found that oil and gas underlie the productive coal measures of Pennsylvania, West Virginia, Ohio, Indiana, Illinois, Kansas, Oklahoma, Colorado, and Wyoming, and, to some extent, the coal measures of other States. The proximity of the known gas and oil areas in the United States to the coal fields and the manner in which the fields overlap in certain States are shown in the map comprising the frontispiece (Pl. I). As the result of many requests received from various sources a conference to consider the protective measures necessary to insure the safety of mining operations in gas and oil fields was called by the Director of the Bureau of Mines to assemble in Pittsburgh, Pa., Feb- ruary 7 and 8, 1913. To this conference were invited a considerable number of gas-well, oil-well, and coal-mine operators within conven- ient distance from Pittsburgh, as well as State geologists and State mine inspectors from a distance. Gas and oil wells are also found near other kinds of mines, such as shale and limestone mines in western Pennsylvania, but these cases are so few that for this and other reasons it was deemed best to con- fine the present inquiry to the consideration of the questions involved in connection with coal mines. It was also not thought advisable to consider the protection of mines from other kinds of bore holes than those for gas and oil, such as coal-prospecting holes, drilled either with churn or diamond drills, or salt wells and artesian wells, because little trouble has been ex- perienced in mining operations from these classes of wells. There- fore the following papers and discussions concern almost entirely the following relations between coal mines and gas and oil wells: (1) Protection of coal mines froin gas and oil wells penetrating -through: (a) Open workings; (b) inaccessible spaces or goaves; (c) pillars, or coal which may be left as pillars. (2) The manner of drilling gas and oil wells passing through workable coal beds so as to provide protection for future mining. The preliminary inquiries of the engineers of the bureau had dis- closed that there was no uniformity in the methods of protecting mines against the leakage of gas from wells, that thousands of wells in coal fields are abandoned yearly without adequate plugging, and without surveys or records being kept to show the location of the holes, from which the casings are generally pulled. According to the State geologist of Pennsylvania, as many as 3,000 wells are being drilled annually in Pennsylvania, 2,000 of these holes being aban- doned within a single year. It is such unplugged, uncharted wells that are the greatest menace in mining. The quantity of gas that the wells produce, although not sufficient to be commercially avail-

Jan 1, 1913

Investigate and demonstrate the possible use of low-density (45-lb/ft3) foam concrete for sealing abandoned mine openings. Although foam concrete has been used in the construction and geotechnical industries for some decades, it has not previously been used in abandoned mint shaft reclamation. Approach A structurally engineered permanent mine seal for an abandoned coal mine shaft, using low-density foam concrete and other appropriate structural materials, was designed by the Bureau and installed at a field site, the No. 22 Shall in Logan County, West Virginia. The field work was conducted by a private contractor under the supervision of the West Virginia AML Section (WV AML). The No. 22 Shaft is situated immediately adjacent to a frequently traveled county road. A few feet away from the shaft is a branch of Pine Creek. On the other side of the road is a railroad line that serves an active mining operation located several miles away. The shaft measures 9.5 by 9 feet in cross section and is about 300 feet deep. It was used at one time as a dewatering shaft and still contains two large-diameter dewatering pipes with steel drive shafts inside them. Before the beginning of the reclamation, the shaft included a concrete cap a few inches thick, with a 4 - by 5-foot access opening covered by a steel grate. The interior of the shaft was quite humid, and considerable flow of water at the bottom of the shaft could clearly be heard from the surface. Methane tests were conducted that showed the shaft to be clear of this gas.

Jan 1, 1992

By R. H. Kudlich

In order to assist the various Federal and State agencies using large quantities of coal to select coal best suited technically and economically to their use, the United States Bureau of Mines has placed at their disposal a fuel inspection service. As part of this service, inspections are made at the mines which propose to furnish coal to these agencies on contracts. Such inspections cover both the mine itself to ascertain its capacity to fur- nish the desired tonnage and quality of the coal, the preparation of the coal in the tipple, and the obtaining of samples for analysis to determine the quality of coal as shipped. To insure that the sample sent to the laboratory for analysis is representative of the average quality of the coal, increments are taken at intervals until a gross sample of about 1,000 pounds of coal has been collected from each of the sizes of coal shipped by the mine, while coal has been coming from all parts of the mine. In reducing this gross sample to the small sample which is sent to the laboratory for analysis it is necessary to crush and quarter the coal by a certain standardized method until only 5 or 6 pounds of coal small enough to pass through a 3/16-inch square-mesh screen remains. The ordinary method which the bureau has followed was to crush the coal by hand with a tamper, such as is used for tamping concrete, on some hare smooth surface and to reduce the volume by quartering and riffling. During the past few years the demands from various Federal and State agencies for this service have been increasing rapidly in respect to bituminous coals. In addition to this, which might be called the normal increase, numerous requests have been received for similar service in respect to anthracite. It was obvious that if this increased demand was to be met it would be necessary either to increase the force allotted to this work or to provide the present force with some means by which their work could be made more effective. A care- ful survey of the situation showed that the greatest amount of time was consumed in trans- porting the men and their equipment from mine to mine in the same district, and in reducing the gross sample to the small finely crushed sample which is to be sent to the laboratory. Both of these phases of the work could be greatly accelerated by providing a motor truck of suitable speed and capacity, carrying a power-operated crusher, and the proper auxiliary equipment to store the gross sample as collected and to reduce it in volume efficiently after it has been crushed. Such a truck has been provided and placed in service. In the eight months it has been in operation the desired results have been fully attained. About twice as many samples as usual have been taken during that time by the same 2-pan crew assigned to this work. Many of the mines in the eastern part of the United States are in hilly or mountainous regions and can be reached only over rough, practically unimproved roads. Hence the speci- fications for the truck were drawn to cover high-quality, long-life trucks, in order that

Nov 1, 1931

By K. C. Strebig

The effect of some organic additives in diamond drilling of quartzite was investigated in the laboratory with a drill instrumented to measure the rate of penetration, the thrust, and the torque and to record each as a function of the distance drilled. A statistical plan was followed throughout the investigation, and an equation representing the bit performance was derived from the mathematical theory of reliability. The coefficient of friction in drilling increased with the use of additives, although the wear coefficient decreased. The decrease in wear associated with an increase in energy per unit volume consumed and the increase in penetration rate resulted in a net decrease in the cost per foot of drilling. A hypothesis explaining the effects achieved with the additives is given.

Jan 1, 1971

By D. W. Frommer

Mineral dressing research was conducted by the Federal Bureau of Mines under a cooperative agreement with the St. Joseph Lead Co., on three samples of iron ore from the Pea Ridge deposit in central Missouri. The objective was to provide information on how to upgrade these submarginal ores and produce marketable concentrates. Samples were prepared from drill-hole cores of similar composition and character to produce (1) a medium-grade mixed hematite and magnetite, (2) a high-grade mixed hematite and magnetite, and (3) a high-grade magnetite. In all three ores phosphorus and sulfur constituted objectionable impurities; excessive amounts of silica were also present in the medium-grade ore.

Jan 1, 1960

By M. Hertzberg

This Bureau of Mines report proposes a new methodology for estimating industrial dust explosion hazards in terms of three probabilities or co-factors: The dispersion of the dust, the existence of a flammable dust concentration, and the presence of an effective source of ignition. This method or rationale is proposed as a replacement for the "explosibility index" that was first suggested 25 yr ago, but which, by consen-sus among leading researchers in the field, is now outdated. This report presents a detailed critique of the deficiencies of that old, material-oriented index, and develops the logical rationale for its re-placement by an approach that is better suited for quantitative hazard evaluations. A variety of such evaluations are illustrated, which show how a quantitative prediction of explosion frequencies can be obtained from laboratory measurements and operating conditions in a given indus-trial facility. The method has some pitfalls, particularly as they re-late to the correlation of events or their randomness. These are discussed, as well as the method's other limitations and uncertainties. This work is intended to provide a beginning to a quantitative approach to explosion hazard assessment. To that end, a new method is proposed for estimating thermal ignition probabilities in terms of the measured laboratory autoignition temperature of a dust, its relationship to the operating temperature, and its distribution within a given industrial system.

Jan 1, 1987

By James A. West

COUNTRIES of the Near East, with the world's largest and insist prolific petroleum resources, produced nearly 277 percent of the world's estimated total output of crude& oil in 1964 and accounted for about 60 percent of world exports of this commodity. Although petroleum largely dominated the mineral industry of tine area, production of antimony, chromium, copper, mercury, boron, potash, and phosphate rock was of world significance. Production of crude oil in Near East countries reached a record high of 7,520,000 barrels per day in 1964, an increase of nearly 11 percent over that of 1963. Kuwait maintained its position as the leading producer, accounting for almost 28 percent of the area's output. Saudi Arabia, Iran, and Iraq followed with 22.5, 22.2, and 16.5 percent of total area output, respectively. Despite record production, the Near East, proved crude oil reserve remained in excess of 211 billion barrels, or more than two-thirds of the estimated world proved crude oil reserve.

Jan 1, 1966

By Benton L. Tibbetts

Comprehensive geophysical measurements were made in the Tertiary Channel gravel deposits of Badger Hill, Calif., with the refraction seismograph, gravimeter, and well logging equipment, to develop a three-dimensional physical model of the gold-bearing gravels. Tests were also made of the applicability of magnetometer and electrical resistivity techniques. Results of 14 seismic profiles revealed four distinct layers with velocities of 1,600 ft/sec for loose gravel, 5,900 ft/sec for compact gravel, 8,600 ft/sec for cemented, blue gravel, and 15,500 ft/sec for bedrock. The depth to bedrock along the middle of the channel varied from a minimum of 100 feet in the hydraulically mined pit area to a maximum of about 300 feet in the upper bench area immediately south of the pit. These geophysical methods revealed that 40 percent of the drill holes necessary to delineate the deposit could be eliminated, at a cost saving of at least 30 percent.

Jan 1, 1971

By E. J. Matson

The Table Mountain copper deposit is in an isolated portion of north-eastern Churchill County, Nev. Although copper-bearing outcrops have been known to exist in the area since 1909, no copper ore has been mined. Development of the property has been hampered by poor roads and rugged topography. Until 1941, the last 4 or 5 miles to the property had to be traveled either by foot or pack animal. As a part of the Bureau of Mines program of investigation and development of domestic mineral deposits, a project was started at the Table Mountain deposit. The Bureau began its field work on July 29, 1947, and completed it on October 18, 1948. Thirteen holes aggregating 2,711 linear feet, were drilled; samples were analyzed - 509 from cores and 143 from sludges. This report contains a brief history of the district and a description of the geology, deposits, and drilling done by the Bureau.

Jan 1, 1949

By R. E. Mussler

As part of an overall goal to develop technology that can maintain an adequate supply of minerals to meet national economic and strategic needs, the Bureau of Mines is evaluating a method for selectively extracting nickel and cobalt from low-grade domestic laterites. The method involves electrowinning to recover the metals in pure form; therefore, preliminary laboratory-scale electrowinning tests were conducted in both a nondiaphragm and a diaphragm cell to determine the effect of variables on energy efficiency under controlled conditions. Electrolytes were generally reagent-grade sulfate solutions that were prepared to simulate electrolyte that could be obtained by stripping nickel-and cobalt-rich solvent extraction reagents. Limited tests were conducted with electrolyte generated from laterite leach solutions. Electrical energy consumption in a nondiaphragm cell was 2.06 kwhr/lb Ni with the cell operated at 50° C, a cell feed of 90 g/l Ni, a pH of 3.5, an extraction of 3.2 g/l, and a cathode current density of 20 amp/ft2. The energy requirement decreased with increasing concentration and temperature, and increased with increasing. extraction and current density. At 50° C, energy consumption in the nondiaphragm cell was 21 pct greater than in the diaphragm cell, but it was only 5 pet greater at 65° C. For this reason and because of overall cost considerations, operation at 65° C with the nondiaphragm cell was preferred. Smooth sheets of cobalt were obtained by electrowinning in a nondiaphragm cell at selected temperatures from 50° to 85° C and with cobalt concentrations from 55 to 87 g/l. The energy consumption (1.48 kwhr/lb) was 22 pet lower with a cobalt concentration of 75 g/l and a cell temperature of 65° C than with a cobalt concentration of 55 g/l and a cell temperature of 50° C.

Jan 1, 1981

By Harold M. Smith

Natural gas has been used as a fuel and source of energy almost from its discovery, but its use as a chemical raw material may be said to have begun in 1918, when Brooks and Humphrey3/ showed. presence of alcohols in the diluted acid oil obtained by the sulfuric acid-treatment of cracked petroleum distillates. However, development of the utilization of natural gas for chemical syntheses was slow, partly because erroneous ideas existed regarding the nonreactivity of tine hydrocarbons composing natural gas. Data accumulated by petroleum chemists throughout the world, particularly since about 1930, have shown that these hydrocarbons will react when activated by the effects of heat, pressure, chemical reagents, and light; also that the reactions can be made to proceed of practicable speeds and to provide good yields of useful products with moderate operating conditions, especially if catalysts are employed. As those results became known, the possibility of a synthetic organic chemical industry based upon these reactions became apparent, and today this industry is large and growing rapidly in importance. In this paper the story of the manufacture of chemical products from natural gas is told simply in graphic form. The industry is developing so rapidly that soma products may have been omitted, but every effort has been made to include all that are important or likely to become so. The difficulty of keeping information of this tape up to date is shown by reference to an information circular4/ or, the sore subject published by the Bureau of Mines in 1930, in which the important products are shown on a single chart, where as five charts are employed for the cane purpose at present.

Jan 1, 1940

This is the eighth in a series of reports en properties of commercial meter fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the United States Department of the interior. The first report gave data en meter gasolines sold during the winter of 1935-36.3/ The present report, covering 1,679 samples, represents the products of 118 companies plus these from the Pacific coast, which were averaged by the Pacific Coast Technical Group before being submitted and are published exactly as they were submitted. The throe groups of data en samples of regular, premium, and third-grade gasolines arc averaged separately. The number of samples and brands representing each grade are as follows: Regular price, 869 samples, 76 brands; premium price, 452 samples, 45 brands; third-grade, 358 samples, 82 brands. In this report the same marketing districts are retained as were used in the preceding report, and as far as possible the actual sampling points in each area arc indicated on table 1.

Jan 1, 1940

[This is the eighth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the interior. The fir t report gave data on motor gasolines sold during the winter of 1935-36.3/ The present report, covering 1,679 simples, represents the products of US companies plus those from the Pacific coast, witch were averaged by the Pacific Coast Technical Group before being submitted and arc published exactly as they were submitted. The three groups of data on samples of regular, premium, and third-grade gasolines are averred separately. the, number of samples and brands representing each grade are as follows: Regular price, 869 samples, 76 brands; premium price, 452 sample, 45 brands; third-grade 358 samples, 52 brands. In this report the same marketing districts are retained as were used in the preceding report, and as for as possible the actual sampling points in each area are indicated on table 1.]

Jan 1, 1940

In this Part, we have included copies of the flip charts and overhead projector viewgraphs used in the two briefings we conducted as part of this seismic detection and location task. The first one was an overview and problem definition briefing given to the seismic consultants on September 7, 1972. The second was a formal oral presentation of study results to technical staff members of the Pittsburgh Mining and Safety Research Center on November 21, 1972.

Jan 1, 1974