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By R. V. Ramani, C. B. Manula, A. Owili-Eger

MINE PROTOTYPE The prototype chosen for application demonstration is from Kingery (1960). The mine and the ventilation plan is presented in Figure 11. A new coal mine is projected with entrance by slope 1,500 feet long. Nine train entries will be standard for development, five as intake and four as return. One return shaft is planned near the slope bottom. The slope will have an area of 150 square feet and a perimeter of 55 feet. The return shaft will be circular with a diameter of 18 feet and will be 500 feet deep. Two hundred feet of the shaft and 500 feet of the slope will be concrete lined. Will it be possible to operate five units per shift with amount of air at each unit not less than 25,000 cfm? Additionally, a shop at the slope bottom will require 10,000 cfm. The problem is completely worked out using standard ventilation formulas and simple manual calculations in the above reference and is reproduced here in Appendix II for ready reference. APPLICATION In this manual, four different applications of the PSU/MVS are outlined. An article by Stefanko et al (1972), outlines how one can move from a mine map to a network for the generation of computer input. Attention is drawn to Figure 12, which is the network line diagram of the mine ventilation system in Figure 11. Note that every roadway junction has been numbered. The dotted lines represent leakage paths and the letter 'R' on a branch denotes that the split is regulated for the quantity shown. For example, there is a leakage

Jan 1, 1975

By A. D. Garman

This paper presents one of a series of digests of foreign mining leg- islation and court decisions which is being repared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countrics. This interpretation of the laws of Panama has been prepared from the best available information in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers to who it is being referr ed through the courtesy of the Department of State.

Apr 1, 1930

By J. G. Groetsch

Municipal solid waste (MSW) contains about 8 pct ferrous metallics which are typically recovered by magnetic separators at municipal resource recovery facilities. At present, only about 182,500 ton/yr of MSW magnetics are being processed for remelting out of the -11 MMton/yr discarded. The Sn in MSW magnetics makes this material difficult to recycle to the steel industry. An electrolytic method using stannous fluoborate-fluoboric acid for removing Sn was evaluated. Optimum concentrations of Sn in the electrolyte and the effects of impurities such as Al, Cu, Fe, and Pb on Sn recovery from the electrolyte were evaluated. Operating parameters were 60 to 65 g/L fluoboric acid and 20 to 30 g/L Sn using stainless steel electrodes at a current density of 60 A/ft2. Tests were run with postconsumer scrap4 and MSW magnetics. Good results were obtained with MSW magnetics, after pretreatment by reshredding, magnetic separation, and air classification. The final Sn content of the MSW magnetics scrap was reduced from 0.18 to 0.017 wt pct. Heat and solvent treatments of MSW magnetics to remove coatings did not significantly improve Sn removal beyond that obtained with material that had only been mechanically pretreated.

Jan 1, 1984

By Jr. Taylor

The following heats of solution have been measured in 1.160 molal H2SO4 at 25° C: AH298, kcal./mole Be(c) + 77.44(H2SO4?47.849 H2O) H2(g) + BeSO4 (soln) -92.83 ± 0.11 BeSO4 ?(c) + 77.44 (H2SO4?47.849 H2O) BeSO4(soln) -16.45 ± 0.02 BeSO4?2H2O(c) + 77.44(H2SO4?47.849 H2O) BeSO4?2H2O(soln) -5.395 ± 0.019 BeSO4?4H2O(c) + 77.44 (H2SO4?47.849 H2O) BeSO4?4H2O(soln) 1.513 ± 0.010 Combining these data with other experimental results and data taken from National Bureau of Standards information yielded the following heats of formation at 298° K:

Jan 1, 1966

By H. H. Schrenk

The safe use of a refrigerant or any substance depends on knowledge of its pertinent properties and conditions of use; therefore some of the properties of refrigerants that are related to life, fire, and explosion hazards are discussed herein. These data serve as a basis for suggested control measures in the use· of refrigerants. The properties of refrigerants may be broadly classified into three main groups: (1) Those important for refrigeration, (2) those significant from the standpoint of confining the refrigerant, and (3) those that become important if the refrigerant escapes from the :machine or container. The first group of properties, such as latent heat of vaporization, specific heat of vapor, specific heat of liquid, etc., is not considered to be directly related to safety and is not discussed here. The second group, those properties important in confining the refrigerants, has particular significance because· it relates to "built-in" safety. This group is emphasized because it is believed the soundest procedure in designing equipment is to give due consideration .to both the health and safety hazards likely to be associated with the equipment. Furthermore, the toxicity, fire, and explosion hazards are controlled as long as the refrigerant is confined. Some properties of this group are (1) stability, (2) corrosiveness, (3) boiling point, (4) pressure developed in the system, (5) warning odor or irritation, and (6) ease of detection. The third group includes such properties as toxicity (of compound and decomposition products), irritating action, and explosibility.

Feb 1, 1942

By J. C. Hartley

The most important single operation in mining is the ventilation of underground areas in a manner conducive to the health and safety of employees. Adequate volumes of pure air must be supplied at the working faces, along the haulageways, and wherever men work, so as to dilute and carry away the methane liberated from the coal and adjoining strata, noxious gases evolved by the use of explosives, and the carbon dioxide exhaled by men and formed by oxidation of carbonaceous material, as well as any other gases, and also dusts which may be found in mine workings. A sufficient quantity of air must also sweep abandoned or worked-out areas of the mine to prevent the accumulation of gases, where sealing methods are not utilized to isolate old workings. Air, in a quantity adequate to meet the needs of the particular mine to which it is applied, is necessary, and supplying it can be made very expensive through failure to observe good practices in its direction and apportionment." Leaky stoppings, doors, and overcasts rob the working faces of air and add to the ventilating cost by burdening the fans with fugitive air,

Jan 1, 1944

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

APPENDIX F GOVERNMENT OFFICES CONTACTED DURING SURVEY 1. MESA Inspection Offices North Central District Duluth, Minnesota South Central District Dallas, Texas Rolla Subdistrict Rolla, Missouri Rocky Mountain District Lakewood, Colorado Salt Lake City Subdistrict Salt Lake City, Utah Spokane Field Office Spokane, Washington Osburn Field Office Osburn, Idaho Phoenix Subdistrict Phoenix, Arizona 2. MESA Research and Management Denver Technical Center Denver, Colorado Pittsburgh Technical Center Pittsburgh, Pennsylvania Metal and Non-Metal Office Washington, D C 3. State Offices (State plan States) Arizona State Mine Inspector Phoenix, Arizona New Mexico State Mine Inspector Albuquerque, New Mexico

Jan 1, 1976

By W. E. Wallace, C. A. Hill, M. J. Keane

"Diesel exhaust particulate material from exhaust pipe scrapings of two trucks, diluted automobile diesel exhaust particulate material collected on filters, and two oil shale ores were prepared for the Ames mutagenrcity assay by dichloromethane OOP ex¬traction, by dispersion into 0.85% saline, or by dispersion into dipalmitoyl lecithin (DPL) emulsion in saline. Salmonella typhimunum TA98 was used to detect frameshift mutagens in the samples. Samples of diesel soot gave positive mutagenic responses with both DCM extraction and DPL dispersion, with the DPL dispersion giving higher results in some cases. The results suggest that possible mutagens associated with inhaled particles may be dispersed or solubilized into the phospholipid component of pulmonary surfactant and become active in such a phase.INTRODUCTIONThe Ames Salmonella/microsome assay (Ames et al., 1975) has been shown to be a useful test for detecting genotoxic properties of various agents. Hundreds of specific chemicals have been screened (McCann et al., 1975), and the test has been applied for many types of environmental samples. Airborne mutagenic agents, for example, have been found in urban air (Chrisp and Fisher, 1980; Hughes et al., 1980; Ro· senkranz et al., 1978), in diesel engine exhausts (Huisingh et al., 1978), and in the by-products of coal combustion processes (Chrisp et al., 1978).Samples of airborne particles are typically collected on membrane filters, and undergo a rigorous extraction procedure with organic solvents and/or ultrasonic agitation (Clark and Hobbs, 1980). Often extracts are transferred to another solvent that is compatible with the assay system. These extraction procedures, while efficient from an analytical perspective, are not physiologically plausible. The questions that present themselves are whether a demonstrated mutagen can be taken up in vivo and whether the process is quantitatively or qualitatively different from the above laboratory procedure (Wallace et al., 1984).When a particle of respirable size is inhaled to the alveolar region of the lung, its first physiological contact is with pulmonary surfactant that lines the inner surfaces of the alveoli. This surfactant is an aqueous fluid containing proteins, phospholipids, and other components (R. J. King, 1982). The principal phospholipid constituent is L·alpha-phosphatidylcholine, beta,gamma-dipalmitoyl, or dipalmitoyl lecithin (OPL) (l. C. King et al., 1981)."

Jan 1, 1989

By Richard F. Hewlett

An attempt has been made to fit assay data from an underground copper deposit to a three-dimensional polynomial surface as a means of expressing assay points in terms of their mine coordinates by a mathematical equation. The resulting equation was evaluated to predict the grade trend of the deposit. Although the fit obtained by this initial experiment is not considered accurate enough to provide good predictions about the deposit, the methodology is presented in this preliminary report to show the potential usefulness of the technique in mineral deposit evaluation. The technique also should be useful in determining the grade of blocks of ore for production scheduling and blending problems in open pit operations. Further experimentation is needed to increase the reliability of the computer program, to increase the precision of the method, and to make the solution more flexible for use on other mineral deposits.

Jan 1, 1964

By F. S. Crawford

This report deals with the effectiveness and economy of installing mine timbers treated with preservatives in long-life service locations. Early in the present century, when mine timbers and labor were plentiful, it was not general practice to install treated timbers in such places. Because national sources of good mine timber are declining steadily, the mining industry must now conserve timber. Moreover, the cost of installing and replacing mine timbers has been rising. Therefore, even the simplest of treatments can be expected to give some return on the investment when applied to timbers that are to be installed in relatively permanent locations. Better methods of treatment will produce better returns. In a service test of maple timbers treated by the hot-and cold-bath method and installed in main haulageways of the Athens mine of the Cleveland Cliffs Iron Co., Negaunee, Mich., zinc chloride-treated timbers had an average useful life of 13.3 years; borax-treated timbers, 11.2 years; and sodium fluoride-treated timbers, 7.7 years. Untreated timbers used as controls had an average useful life of 3.8 years.

Jan 1, 1950

By D. M. Soboroff

Etchants containing hexavalent chromium and sulfuric acid are used in a variety of surface-finishing operations. When the resultant spent solutions are discarded, substantial quantities of chromium are lost and pollution prob¬lems are created. To minimize the undesirable environmental effects while improving metal and minerals recycling technology, the Bureau of Mines is conducting research on a method for the economic inplant recycling of these waste etchants. Trivalent chromium, produced when the etchant reacts with a sub¬strate, is oxidized in the anode chamber of a diaphragm cell; other metals, dissolved during the etching operation, are transferred to the catholyte. When waste brass etchants are treated in this manner, all of the trivalent chromium is oxidized and more than 40 percent of the copper and zinc is removed. Similar copper removal and chromium oxidation are achieved with waste printed circuit board etchants and rinse waters from plastic etching operations. The electrical energy needed to regenerate 1 kg sodium dichromate is less than 9 kwhr. Regenerated brass etchants evaluated by two companies equaled or exceeded the performance of fresh etchants.

Jan 1, 1979

By M. G. Zabetakis

This publication presents a simplified graphic method for determining the explosibility of mine atmospheres under mine-fire conditions from mine- atmosphere composition data. Sometimes it is necessary to seal part of a mine during a fire to exclude air and thus extinguish the fire. Unfortunately, liberation of methane and formation of hydrogen and carbon monoxide in the sealed area may create an ex- plosive or flammable atmosphere if enough oxygen is present to support combustion. On the other hand, the oxygen concentration may be reduced through combustion processes and the concentration of inert gases (nitrogen and carbon dioxide) increased enough to render the atmosphere within the sealed area non-explosive. Before an area is unsealed, it is extremely important to know if the sealed atmosphere contains Flammable gases in proportions that might form explosive mixtures when air is introduced. If an explosive mixture forms and the fire is rekindled, a gas explosion will result. Various experimental methods may be used to determine the explosibility of a particular mine atmosphere; however, these methods usually are impracticable in the field.

Jan 1, 1959

By E. D. Gordner

U. S. Bureau of Mines

Jan 1, 1923

By L. C. IlsLey

In the normal operation of mines, the aggregate effect of many seemingly minor op rations may be very important as respects economy and safety. Anion: these operations is the method employed in coupling and uncoupling mine cars. For economic reasons the equipment in mines has not been protected as well as railroad equipment. It is pertinent that haulage accidents rank second in severity among mine accidents, and that manual coupling of cars has been one of the most frequent causes of such accidents. One study4/ revealed that coupling was responsible for about 20 percent of haulage accidents underground. A review of early conditions on steam railroads, which were responsible for the introduction of safer methods of coupling cars, indicates how conditions in might be improved. THE STORY OF RAILROAD COUPLING As any considerable improvement in mine-car coupling probably will follow lines somewhat similar to those that brought order out of chaos for the railroads, it seems appropriate to review briefly the steps taken to improve railroad coupling from the days of link and pin couplings of various types to the adoption of the standard ?M.C.E? automatic coupler.

Jan 1, 1943

By H. O. McDonald

Solutions containing Cr6+ and sulfuric acid are used in a number of surface-finishing operations. Substantial quantities of chromium and copper are lost and pollution problems are created when the spent solutions are discarded. To minimize the undesirable environmental effects while improving secondary resource recovery technology, the Bureau of Mines is conducting research to detoxify and recover metals from these solutions. Spent etchants are treated to remove copper and reduce Cr6+ to Cr 3+ in an electrolytic cell. The anodes and cathodes are granulated coke. The spent solution is continuously pumped through the electrodes. Hexavalent chromium is reduced to trivalent chromium, and copper is recovered at the cathode. Reoxidation of Cr3+ at the anode was not observed. The removal and recovery of copper reduction of Cr6+ lessen chemical demand and increase efficiency in waste in treatment operations associated with the use of these solutions.

Jan 1, 1980

By Dana Reinke, William Wiehagen, Launa Mallett, Charles Vaught, Kathleen M. Kowalski, Michael J. Brnich, Lynn Rethi, Lisa Steiner

Safety and health professionals from all sectors of industry recognize that training is a critical element of an effective safety and health program. A major concern in the mining industry today is how to train the present aging workforce plus the expected influx of new and less experienced miners and mine operators as the cohort of older workers retire. This paper defines the problem, offers a model to structure the inquiry, and presents the key issues a multi-disciplinary team of NIOSH researchers identified, based on an extensive review of the current literature in relevant areas. Issues include differences between cohorts, such as the newer workers (Generation M), and present workers (Boomers) with respect to their physical, social, psychological, and cultural characteristics, their learning styles and work expectations. Specific issues for an aging workforce are discussed. Some preliminary recommendations are offered on the type of training needed.

In this U.S. Bureau of Mines report, proposed narrow-vein and longwall mining concepts using drill-split technology (described in part 1 of this series) and in situ liner concepts (described in part 2 of the series) are combined and applied conceptually to environmental problems. Proposed applications deal with (1) acid mine drainage (AMD), (2) solid waste disposal, (3) site remediation, and (4) pollution prevention through innovative industrial design. For control of AMD from abandoned hillside mine workings, it is proposed that source veins be re-mined, processed for residual values, then backfilled using an impermeable compound backfill mix. For solid waste disposal, "vertical landfills" are proposed, consisting of trash-backfilled underground rock quarries. Vertical landfill activities take place in in situ lined containments that geohydrologically isolate the mining-backfilling activities. Site remediation through the creation of in situ underliners, for the capture of toxic leachates, and pollution prevention through the underground storage of toxic, flammable, and explosive materials in in situ containments, are proposed.

Jan 1, 1995

By H. D. Baylor

This paper, describing the operations of the Louisville Cement Co. in quarrying limestone for the manufacture of quicklime, is one of a series being prepared for and published by the United States Bureau of Mines on stone quarries throughout the United States. Those papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual operators as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. ACKNOWLEDGMENTS The author acknowledges the assistance of J. H. Lemmon, plant superintendent, Charles Taylor, plant engineer, and F. H. Compton, chief engineer, of the Louisville Cement Co. in the compilation and preparation of this paper.

Jan 1, 1932

By John S. Dunning

This is one of a. series of papers being prepared for and published by the United States Bureau of Mines, describing raining and milling methods at crushed-stone plants throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total production costs. It is recognized that publication of total production costs might in man; instances cause embarrassment to individual producers as well as to the industry as a whole. However, operating costs are essential to technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that the scope of the cost tabulations shall not be misunderstood. This paper deals with the quarrying and crushing methods used at the Avon Mountain trap-rock quarry of the Atlas Sand, Gravel & Stone Co., in West Hartford, Conn.

Jan 1, 1936

By D. J. Parker

The oft-repeated expression that the taproot of safety lies in the attitude of the management toward accident-prevention work is indisputable and has become almost an axiom. Trite and somewhat timeworn though the statement may be, it is nevertheless true that the supervisory force must earnestly support a policy of safety and maintain at all times a con¬ siderate regard for the welfare of the employee if that high degree of cooperation of the employee, so vital to the successful prosecution of any safety program, is to be expected. The responsibility for preventing accidents rests upon the management, and in the case of the Spring Canyon Coal Co. such responsibility is recognized and accepted with little or no reservation. This company, aside from the humanitarian aspects involved, believes that safety is good business and not a matter to be treated passively or in a perfunctory manner. The problems with respect to safety that have been met and wholly or partly solved can best be appreciated when some of the natural conditions, adverse and otherwise, existing at this operation are taken into consideration. Mine 1 is about 1 mile north of the town of Spring Canyon, Carbon County, Utah, and is served by both the Denver & Rio Grande Western and Utah Coal Route railways. During the year 1931 the mine produced 312,397 tons, approximately 10 per cent being derived from pillar workings. The normal daily output during the summer months is about 2,000 tons, and during the peak of production in the winter season the daily production varies from 2,500 to 3,000 tons. The number of miners varies from 87 in summer to 220 in winter, and the day men vary in number from 66 in the winter to 45 in the summer; 12 company men are employed the year around. The officers of the company are J. B. Smith, president, San Francisco, California; T. R. Stockett, general manager, Salt Lake City; and G. A. Murphy, superintendent, David Brown, assistant superintendent, and John Sullivan, mine foreman, all of Spring Canyon, Utah.

Dec 1, 1932