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By Michael Rieber

Among the principal gathering/distribution systems for coal is over-the-road trucking. Where alternative trunk line modes such as barge or rail links are weak or nonexistent, trucks may, particularly for relatively short line hauls, act as substitutes. Their major application, however, appears to be in connection with smaller mines or coal users particularly where terrain problems are significant. Truck use has increased as rail lines have been abandoned or suffered neglect. For example, in 1956 about 38 percent of the coal transported in eastern Kentucky and about 8 percent of the coal moved in western Kentucky went by truck. By 1975, the percentages were almost 77 percent and 26 percent, respectively [4,U-11]. While rail route .limitations and deterioration played a part in the change, increased emphasis on road building, particularly during the 1950's and 1960's, and improved truck load capacity and efficiency were also important.

Jan 1, 1977

By Lyman C. Hitchcock

The objective of this program was to determine the minimum luminance requirements for underground coal mining work from the working face to the first transfer point. The resulting data encompasses 114 visual tasks from conventional continuous and longwall mining methods representing the salient visual tasks found in the jobs listed. Cutter Operator Roof Bolter Face Drill Operator Airdox Operator Longwall Jackman Shuttle Car Operator Loader Operator Shot Fireman Continuous Miner Operator Longwall Head Conveyor Operator Longwall Tail Conveyor Operator

Jan 1, 1973

By Clarence Karr

RESINS from a bituminous pitch, a bituminous coal, a lignite tar, a subbituminous pitch, and an electrode binder pitch wore investigated by the Bureau of Mines. The compositions of these resins were determined by four independent methods of structural detemination: (1) Molecular formula and ring analysis, including ring (2) infrared and ultraviolet spectra; (3) combined pyrolysis/gas chromatography, and (4) catalytic dehyrogenation followed by spectra and pyrolysis. The resin structure was correlated with coal structure, and it was concluded that pitch resins probably consist of essentially unaltered coal molecules carried over with the tar vapors in low-temperature carbonization.

Jan 1, 1966

By Thomas C. Denton

ALL of the 45 political divisions of Africa were accessible to non-Communist world industry and commerce throughout 1964, although in some of them revolt and political attitudes presented problems. The position of the continent as a whole for mineral and mineral fuel resources, production, and oversea exports continued to improve. At yearend, significant quantities of a greater number of mineral commodities vital to industry and agriculture were being produced than in any other continent. This statement excludes Communist areas on other continents but might well hold true even if such areas were included. Deriving from its exceptionally diversified production, Africa furnished overseas industrialized countries as a w ole a greater variety of key mineral commodities than any other area. In addition, the value of mineral imports from Africa into the United Kingdom and continental non-Communist Europe probably exceeded the value of such imports from any other area if gold is included and mineral fuels excluded.

Jan 1, 1966

By D. Harrington

The record of fatalities from mine explosions in the United States during the past 44 years has been the best in the history of the mining industry, despite the fact that the number of fatalities from this cause during the past fiscal year now is nearly double that of the previous year. During there 4 fiscal years, mine explosions have resulted in an average of 45.5 deaths per year, compared with an average of 153 deaths per year for the preceding 5 years; an average of 542 deaths per year for the 3 years 1907-1909, inclusive, and a yearly average of 265 deaths per year for the 20 years prior to 1929. Other types of mine accidents also have been reduced during this period, but not to the same degree or by as large a percentage as mine explosions. The fact that in this fiscal year ended June 30, 1937, electricity was responsible for 60 percent of the explosions and 85.5 percent of the fatalities resulting therefrom (see tables 3 and 4) is evidence that either mine operators are lax in providing proper electrical equipment or there is laxity in the upkeep and use of electricity in our mines and more particularly in our coal mines. Several large coal-producing States that in the Fast have had numerous disastrous explosions have been free from such disasters for continuous periods of as long as 8 years. The bituminous mines of Pennsylvania, one of the largest coal-producing States, give a good example of what can be done to prevent explosions. 'his State, with its large number of operating mines, many with very definite hazards from gas or dust or both, has had only two major explosions (resulting in 16 fatalities) during the past 7 years; this is a decidedly good record compared with any similar period in the past and when it is considered that during this period about 750,000,000 tons of coal have been produced. Other good records are: Tennessee, without a single fatality from explosions during the past 9 years; Alabama, with 6 fatalities during the past 7 years; Illinois, with no explosions during the past 4 years; and

Jan 1, 1938

This Bureau of Mines report and its companion report (Information Circular 9142) have been prepared to assist in the preparation of prefeasibility type estimates for capital and operating costs of beneficiation of various types of mineral occurrences using current technology. The handbook provides a convenient costing procedure based on the summation of the costs for the unit processes required in any particular mining or mineral processing operation. The costing handbook consists of a series of costing sections, each corresponding to a specific mineral processing unit process. Contained within each section is the methodology to estimate either the capital or operating cost for that unit process. The unit process sections may be used to generate, in January 1984 dollars, costs through the use of either costing curves or formulae representing the prevailing technology. The mineral processing handbook includes individual cost estimation sections for unit operations associated with comminution, beneficiation, solid-liquid separation, hydrometallurgy, and special applications as well as infrastructure and plant general and administrative costs. When using this system for estimating cost data for a mineral processing facility or for checking or verifying processing costs from an existing facility, a minimum amount of background information is necessary.

Jan 1, 1987

By D. J. Parker, D. Harrington, L. H. Harrison

"INTRODUCTION The necessity for protection against the hazards of lightning manifests itself from time to time in the mining industry by reason of loss of life, damage to electrical equipment, fires in surface structures at mines, and accidents in the handling and use of explosives. This paper is intended to assemble, correlate, and present some of the salient points embodied in the available literature on the subject and at the same time give some factual data concerning instances of such loss of life and damage to property, with special application to the mining industry.The annual loss of life and destruction of property by lightning is considerable; the former may be prevented to a limited extent, though use of common sense as to exposure is required and not always followed; the latter can be prevented to a considerable degree. The manufacturers of electrical equipment, through improved types of lightning arresters, have done much toward the protection of electrical equipment, with consequent safeguarding of life and of property. Education based on unfortunate experiences has gone far to discourage the handling of explosives and blasting accessories during thunder storms, especially in open pits and quarries, and to a much smaller extent in underground workings. The lowly lightning rod plays an important role in the protection of certain types of buildings (especially isolated buildings), stacks, monuments, and other structures.LIGHTNING PHENOMENAIn 1751, Franklin proved that, lightning was simply a visible display of electricity - an extended spark; and until a generation ago little had been added to his exposition to define the various phases of the phenomenon. Matters pertaining to lightning are discussed in the following references:"

Apr 1, 1948

By H. S. Auvil

[Coals of low-volatile rank cannot be coked without admixing large proportions of high-volatile coal in the usual type of byproduct-coke oven, because they expand excessively and exert side thrust, which ruins the oven walls. Some medium-volatile coals also give trouble. Since high-rank coals produce a strong, blocky coke, it is desirable to have the rank as high as practicable, particularly in the manufacture of foundry coke. Accordingly, it has become the practice to mix or blend high-volatile shrinking, coals with as much low-volatile coal as possible and still have a mixture that will not deform the walls or cause difficulty in pushing the coke. Occasionally, the safe limit of low-volatile coal has been exceeded and ovens have been damaged. It is desirable, therefore, to rave a reliable method of determining the expanding tendencies of mixtures before they are charged into the ovens. Furthermore, coal charges somewhat in its properties as mining progresses, and therefore, mixtures found to be safe at one time may cease to be so subsequently, particularly if nearly the maximum allowable percentage of low-volatile coal is being used.]

Jan 1, 1938

By Oliver C. Ralston

[The NOJ'l..metals Division deals wi tt mi:leral n t inte .ded to be used a ra\o,f materials for extraction of metals. ~ _ ereas, a. materinl containing a chromite, if used' for production of c~1r()rrti1..1r.'l ::tetE' .. l or fcrrochromiu"1, 1,oJould be a chromi te ore, if used as 8. rcfrn.cto~J or for prod .1.ction of chromium chemicals, it is a chromi te-beari [. ~?oCl... Li;{eHise, a r:1a&neti te used for production of iron is a metallifero"'..ls ~in8re..i; if used 8.S a water-filtration granule in .:l magne.tically cleaned filter bed, it 'ould be a nonmetallic in-dustrial mineral.]

Jan 1, 1940

Watershed Jll in Jefferson County, Ohio we instrumented in 1977 as one of three watersheds established for the purpose of investigating surface mining and reclamation effects upon local hydrology, sediment discharge, and sediment and water quality. Each watershed was less than 50-acres in size, and was in a different geologic setting within southeastern Ohio. Surface runoff and ground¬water levels were monitored. Samples were taken for sediment determination and chemical analysis prior to mining. Monitoring and sampling continued through the period of watershed disturbance caused by mining and reclamation activities, which began in May 1980 at Watershed Jll. A psuedo-postreclamation period followed the initial cessation of man-machine activity on the watershed. A second reclamation effort occurred in the fall of 1981 and was to be followed by a third in 1982 after observations ceased. A true final postreclamation period was not monitored at this site, because the erosion control practice (terrace diversions) failed after each reclamation. Watershed Jll was a small pasture and wooded watershed with sandstone and shale above the mined coal seam prior to mining. A clay layer under the coal supported a perched saturated zone, termed the top aquifer for convenience. A lower underclay supported a second saturated zone called the middle aquifer. A lower perched aquifer had been dewatered by previous deep mining. After about three years of premine data and about two and one-half years of mining reclamation and psuedo-postreclamation data, the following general observations may be made: 1. The mining-reclamation phase was very short, and the postmining period was characterized by erosion failures and remedial disturbances that kept the watershed condition and size in a state of change. It was impossible to collect sufficient data to confidently characterize the hydrologic-sediment-chemical aspects of the mining period or of a postreclamation period and, most importantly, of the future watershed after its various properties and characteristics have ceased adjusting to its severe disturbance and reconstitution. 2. A seeding of wheat followed by grasses and legumes was not a particularly successful reclamation practice in terms of stabilizing the new soil. Numerous rills and small gullies developed in spite of installed diversions. 3. Storm runoff rates and yields at the watershed outlet increased from the premine, (phase 1) to the mining-reclamation (Phase 2) periods, and remained at or near the Phase 2 level through the postreclamation (Phase 3a) period. 4. The top aquifer changed in physical and chemical character as a result of mining and was becoming reestablished as the project drew to a close; but it is impossible to predict its final configuration or character. 5. Dewatering of the top aquifer resulted in a complete cessation of baseflow because the middle aquifer water table lay below the elevation of the watershed outlet. 6. The top and middle aquifers were merged in one area of the watershed where the upper coal underclay was disturbed. 7. Failure of the diversion terraces and their outlet obscured the effects of the reclamation practice upon sediment concentration and yields. There was little difference in sediment concentrations between Phases 2 and 3a. 8. Drinking water standards were met by surface waters throughout the period of observation except for two samples that exceeded the nitrate-N allowable level of 10 mg/l. 9. In all Phase 3 surface-water samples, iron concentrations were within the limits established by OSM, and manganese concentrations exceeded the regulation level only once. pH fell below the lower regulation level of 6.0 between 10% and 20% of the time. 10. The chemical quality of sediments was generally about the same after reclamation as before mining, with the exception of organic carbon, which decreased.

Jan 1, 1983

By Phillip N. Yasnowsky

The thrust of this Bureau of Mines report is to relate the size of automobiles to the price of gasoline, and the use of minerals in automobile manufacture to the size of automobiles. Only one of the many plausible scenarios of public reaction to higher gasoline prices, a switch to economy size automobiles, is developed. No account is taken of other potential impacts such as improvements in public transportation or increased occupancy per vehicle. Furthermore, a gasoline price increase is the only incentive to the greater utilization of economy cars that is considered. A gasoline price increase to $0.60 per gallon would reduce the amount of minerals required to produce the automobiles sold in the United States by an estimated 15 percent. Gasoline prices of $0.80 and $1 per gallon would cause declines in mineral requirements for U.S. automobile sales estimated at 26 percent and 35 percent, respectively.

Jan 1, 1974

By Ludwig Schmidt

The disposal of the brines produced with crude petroleum and natural gas has long been a constant source of trouble to oil and gas operators as well as to farmers and stock-raisers in the vicinity of producing fields. The amount of oilfield brines Produced from wells on new properties may be almost negligible, but some older wells may produce several hundred barrels a day. A survey of almost 200 wells on 31 properties in the eastern part of Osage County, Okla., showed that during the month of November, 1928, the average production of water was 3.26 barrels per barrel of oil produced. The age of the wells included in this survey ranged from two to 28 years; the maximum amount of brine produced was 26 barrels of water to one barrel of oil and the lowest was one barrel of water to 27 barrels of oil. These figures apply to a small area. In other fields the production of water also varies widely; for example, in the Cushing4, Okla., field several yells were reported as having produced 100 barrels of water to every barrel of oil produced. Often the production of oil-field brines is decreased materially and the production of petroleum increased by the use of bottom hole Plugs and by a general repair and cementing of wells. The records5 of 22 wells cemented in the Gushing field showed that prior to the repair work, the average total dally production was 242.5 barrels of oil and 3,977.5 barrels of water. The total Production of

Jan 1, 1929

By C. H. Fisher

[Mxny methnhs of ,analyzing tpr oils fnr thoir tar acid ~nd base cnntent hava boon employL~d in connection mith both ac~d,.mic and. industrial investigs- tions. Mnst of thznu nnalyticel proc?durn~s aro bpsed nn th; diminution in volums caused by extract lon sit5 alkali 5 minL+ra,l acids (cantrsction rn,>thod) , although othrr mr~thrids havu &apos;sL<on ?q~lnglt 8 . In many instmccs th-: donti ti on of RT~ m~lytic~l m ithod was not ;r.:c ~d~d by ~d.jqunt9 study, and, ns 3 cone+ qucnce, tha lit .,ratur ? on thls sub,jr:.ct is consoScuous for its cnntr~dictnry . claims and rocnmmondatinna.. 1.t tiR.s b9~n shoyn in th;, cnsn of c.lrtn.in synth?tic solut innsfi/ thnt larg~ jr-orn sny rcsult if th2 ,mnlysis is c~rri~d out by sim~la extraction wi.th alidi r.nd min 3rd ncids.]

Jan 1, 1937

By Wm. O. Vanderburg

This report on the mining and milling of tungsten ores is the second part of a general study of the domestic tungsten industry. The first part, comprising general information on tungsten, has been printed as Bureau of Mines Information Circular 6821. The purpose of these papers is to increase efficiency in the mining, preparation, and utilization of the tungsten resources of the United States. The tungsten industry forms so small a part of the vast mining and metallurgical operations of the illation that private metallurgists have not had enough inducement to give special attention to the recovery of tungsten minerals from the ores, and many of the small companies are financially unable to undertake research work. A study of the milling of tungsten ores reveals that further improvement is possible, especially in the treatment of slimes. Recent experimental work by the Bureau shows that the flotation process is applicable to certain tungsten ores. The future of the tungsten industry it the United States depends to a great extent on utilization of the low-grade deposits of the contact-metamorphic type.

Jan 1, 1935

The Mine Safety and Health Administration (MSHA) defines an independent contractor as any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine. Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Jan 1, 2008

By Lloyd A. Morley

Proposed advantages and disadvantages of low-voltage shielded trailing cables are formulated utilizing the literature and industry sources. A partial analysis of these proposed advantages and disadvantages is completed through a review of the literature. Cable costs are assembled from mine operators, cable and splice manufacturers, and actual cable purchases. To confirm each advantage and disadvantage, an underground test site is established, and testing is performed here and in the laboratory. All testing procedures are completely described. The results of this investigation are reported and used to formulate recommendations attendant to low-voltage shielded cables. Suggestions for installation, handling, and maintenance are presented.

Jan 1, 1977

By Leonard P. Vitt

This report details the work done to provide the U.S. Bureau of Mines with a customized Wireless Ground Monitor Wireless Ground Monitor was modified as follows: 1. A voltage regulator was added to prevent false trips with line voltage variations. 2. A Ground Wire Trap was designed to eliminate problems with parallel paths and provide spark suppression. 3. A three phase filter was designed to reduce 60 Hz leakage current. 4. A portable tester was designed to permit complete test of installed systems. 5. The design was modified to insure trip with an open ground wire in the event of a failure of any one semi-conductor component.

Jan 1, 1976

Ground and air vibrations induced by large surface blasts have been monitored. These field results, as well as a large number of published results, have been used to assess the performance of existing predictors and for the development of improved prediction methods. Field monitoring has been performed, with four seismographs giving complete wave records, at limestone quarries, coal strip mines and an open pit copper mine. Conventional analysis includes least square fitting of peak particle velocities and peak air overpressures with scaled distance formulations. Frequency content has been analyzed, and correlated with blast design (detonation sequence). Two new methods have been developed for predicting ground vibrations induced by blasting. The proposed analytical predictor accounts explicitly for inelastic attenuation and geometrical spreading, and calculates the peak particle velocity as a function of charge weight and distance. Statistical analysis of case studies confirms the consistent improvement over conventional scaled distance predictors. The second new predictor is a computer program simulating blasts, including blast geometry, charge distribution and detonation sequence, and simulating propagation of individual pulses to any point of interest, where effects are summed. A complete blast vibration results, allowing prediction of frequency content and duration as well as peak velocities.

Jan 1, 1983

By W. W. Adams

The quantity of explosives sold in the United States in January, 1931, for domestic consumption, amounted to 368,100 kegs (9,202,500 pounds) of black blasting powder, 4,610;000 pounds of permissible explosives, and 16,533,000 pounds of high explosives &apos;other than permissible. These figures are based on reports received by the United States Bureau of Mines, Department of Commerce, from nearly all manufacturing companies, and include an estimate of sales by several companies that do not furnish monthly reports. Reports actually received from manufacturers showed soles of 365,977 kegs of black blasting powder (consisting of 220,892 kegs of granular powder and 145,085 kegs of pellet powder), 4,687,900 pounds of permissible explosives, and 15,496,152 pounds of high explosives other than permissible. Sales in January, 1931, were smaller than in January, last year, the decreases being 14 per cent for black blasting powder, 19 per cent for permissibles, and 17 percent for high explosives other than permissible. Sales in January 1931 when compared with soles in December 1930, show increases for all three classes of explosives as follows: 2 per cent for black blasting powder, 16 per cent for permissible explosives, and 7 per cent for other high explosives.

Jan 1, 1931

By H. E. Harris

It has long been recognized that one of the principal ways of combating dust in coal mines is by means of water sprays. However, spray systems, currently in use, clog or plug frequently, thereby reducing the effectiveness of dust control aid, in turn, possibly increasing the health hazard to mining personnel. Moreover, the maintenance and replacement of spray system components, e.g., nozzles and filters, can be expensive in terms of direct costs of labor and material, and the consequent loss of production. Recognizing these problems, the Bureau of Mines sponsored a research project on the "Development of a Non-Clogging Water Spray System"; this project was carried out by Eastern Associated Coal Corp. The overall objective of this project was to develop a non-clogging water spray system suitable for use in underground coal mines. Since most of the dust formed is at or near the working coal face, emphasis was placed on face equipment such as a continuous mining machine. To accomplish this objective, a two-phase project was carried out. The first phase involved determining the causes of spray nozzle and spray system clogging, determining the availability of spray nozzles or systems that could be modified to be non-clogging, and developing a non-clogging water spray system. Phase two was concerned with the fabrication and the laboratory and field testing of a non-clogging system. In each phase, there were both laboratory and field investigations, and the results of these investigations are presented in this report.

Jan 1, 1975