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By Ronald F. Balazik

This Bureau of Mines study identifies and examines the costs of Federal, State, and local environmental protection controls on domestic phosphate rock mining, The costs include the expenditures needed to comply with government regulations and the effects that these expenditures and regulations have on supply. The study analyzes costs of environmental impact assessments, air and water quality standards, reclamation laws, potential solid waste controls, and local government restrictions. In addition, an industry survey and the Bureau's Minerals Availability System (MAS) are used to evaluate land management policies that restrict access to phosphate resources, Conclusions drawn from these analyses confirm that (1) domestic phosphate mining has incurred substantial control costs and may be subject to significant new regulatory costs in the next several years, (2) certain environmental controls can discourage mining investment, (3) environmental policies governing land-use controls affect the disposition of sizable phosphate resources, and are key determinants in the development of those resources on the Federal do- main, and (4) environmental costs could diminish the competitiveness of domestic producers.

Jan 1, 1983

By Sara Jane Boles

In recent years the demand for products of greater refractoriness has placed an ever-increasing emphasis on ceramic materials, including the metallic oxides. Magnesia (MgO) is one of the most important of these oxides, exhibiting, as it does, high electrical resistivity, high slag resistance, and a melting point of 2,800° C. However, magnesia has a tendency to hydrate in the presence of water and to volatilize above 1,500° C. in certain kiln atmospheres and has a comparatively low resistance to thermal shock. Because of these disadvantages, the previously listed advantages inherent in this material have been largely overlooked, and research on magnesia has lagged behind that on oxides such as alumina and zirconia. This bibliography has been prepared in an effort to present to Government and industry a comprehensive picture of the prospects for greater utilization of magnesia as a refractory material in future research. To provide as selective and accurate a collection as possible, the references included cover magnesia in a pure state, not as an additive or in combination with other materials. However, several references discuss the effect of minor impurities (less than 5 percent of the total) on the properties of magnesia, as these papers are considered to be of special importance. A few references to articles on forming techniques are also included, as they are valuable additions to the overall treatment of the subject. The processes used in obtaining and refining the raw materials are adequately covered in earlier publications and are excluded. A number of references are omitted as being of questionable value in enhancing the cumulative study of pure magnesia as an ultra-high-temperature refractory material.

Jan 1, 1962

By D. Harrington

This circular presents part I of a series of papers of a review of the literature on air conditioning in mines, with particular reference to the health, safety, and efficiency of miners. It deals with the physiological aspects of exposure to air contaminated by organic matter, noxious and toxic gases, and dusts that emanate from various sources in underground workings; part II will discuss the relation of abnormal mine temperatures and humidities to the health and efficiency of minors; and part III will describe theoretical and practical methods of air conditioning mines to correct or alleviate the conditions mentioned and will discuss the results attained by some of the systems now in use in various parts or the world.

Jan 1, 1938

By Earl Redman

The Juneau Gold Belt portion of the Juneau Mining District has historically had the greatest mining and exploration activity within the district. Between 1880 and 1983, the mines within the Juneau Gold Belt produced 6.7 MM oz gold, 3.1 MM oz silver, and 45 MM lbs lead, which had a total value of about $157,000,000 at the time of production. This report summarizes Bureau of Mines work completed in 1986, the second year of the Juneau Mining District study. Fifty mines, prospects, and occurrences were examined and 638 samples were collected for analysis during 1986. Metallurgical samples were collected from seven deposits and preliminary tests of cyanide amenability have been completed for five of these. The simultaneous discovery by private industry and the Bureau of gold-bearing quartz veins cutting diorite gneiss recently exposed by the retreat of the Herbert Glacier is the most notable result of work during 1986. This location yielded gold values up to 7 oz/st.

Jan 1, 2011

By Howard W. Wainwright

This bibliography was compiled by the Bureau of Mines as part of an investigation into the possible utilization of low-temperature coal-tar bases. The bibliography consists of literature and patent references from about 1945 to 1961 and is divided into the following headings: Analysis and Composition; Production, Synthesis, Reactions, and Utilization; and Separation, Purification, and Properties. Although over 1,000 references are included, no attempt was made to insure a comprehensive survey. The literature and patent references are arranged alphabetically by author or patentee. When several publications have the same author they are listed in reverse order of age, with the newest first. An author index is included because secondary authors are not cross-indexed. In almost every instance, the entry is accompanied by a Chemical Abstracts reference for those interested in locating an abstract of the original paper.

Jan 1, 1962

By P. J. Remington

Field measurements utilizing a seat pad accelerometer were made on 25 underground coal mining machines in order to quantify the vibration levels experienced by the operators. Those data were combined with information on the statistics of the operating times of those machines in order to compare the operator's vibration exposure to the criteria in ISO 2631, "A Guide for the Evaluation of Human Exposure to Whole Body vibration." The comparison showed that about 30% to 40" of all underground coal mining machine operators can be expected to be exposed to vibration exceeding the fatigue decreased proficiency criterion, whereas only 10 to 15% would be expected to experience vibration exceeding the exposure limit. The primary sources of the exposure are shuttle cars and possibly scoop trams. Detailed exposure statistics are presented and the implications of the results are discussed.

Jan 1, 1983

By Fred E. Fiedler

A demonstration project investigated the feasibility and effectiveness of two management interventions, Management Training and Organization Development, for improving productivity and safety in metal/non-metal mines. The management training intervention was conducted at Texasgulf Company's trona mine, using three nearby trona mines as controls. The Organization Development intervention took place in Hecla Mining Company's Lucky Friday mine, using the highly similar Star Mine as control. The two management interventions seemed about equally effective in reducing accidents and injuries, as well as MSHA citations, and the management intervention at the Texasgulf mine also appeared to have led to substantial improvement in mine productivity.

Jan 1, 1983

By E. K. Stanek

This research study was performed on a case study basis and can be divided into two parallel thrusts: electrical and thermal energy conservation. Energy consumed annually in mining and refining operations represents about 6% of the 80 quadrillion Btu's consumed nationally. In the electrical portion of the study, five areas were addressed: optimal dispatching of on-site generation, high-efficiency motors, conductor selection, power factor correction, and high efficacy lighting. In the case study mine which has a multiple unit on-site generation system, optimally dispatching units can save significant energy. The other four methods are difficult to justify on a retrofit basis due to capital costs. In the thermal portion of the study, a thermodynamic analysis was performed on the reverberatory smelting process possible areas of energy conservation were identified as radiation and convection heat losses from the furnace arch and the dumping of high energy content smelting slag. It has been shown that materials currently available can provide the means of reducing heat loss from the reverberatory furnace. It has also been shown that a significant amount of energy may be recovered from the slag. However, these are both subject to further study and validation.

Jan 1, 1982

By Francis E. Federspiel

In 1984 and 1985, at the request of the U.S. Forest Service, the U.S. Bureau of Mines examined the 87,720-acre South Boise Yuba study area (formerly known as RARE II Wilderness Recommended area I-4553) to evaluate mineral resources. The study area and additions are in Blaine, Camas, and Elmore Counties, 10, about 60 mi east of Boise. Granitic rocks of the Cretaceous age Idaho Batholith occupy the western two-thirds of the study area. A Tertiary age granitic complex has intruded, and broken into small blocks, Paleozoic age sedimentary rocks in the eastern third of the study area. Tertiary Challis Volcanics overlie both of these rock types. Principal mineralized structures are gold-and silver-bearing quartz veins and shear zones trending northwest to easterly in the Cretaceous granitic rocks. Copper, lead, and zinc are accessory metals in many mineralized structures.

Jan 1, 1987

By G. D. Bakulev

Economic Importance of Gasification of Fuel and Brief Outline of Development of Underground Gasification of Coal in the U.S.S.R. The underground gasification of fuel offers a number of economic and social advantages, principally the following: 1. Full automation of labor-consuming coal-mining processes, which resist complex mechanization and automation, particularly shaft mining. 2. Elimination of hard, dangerous, and often unhealthful mining work. 3. Creation of hygienic conditions for personnel employed in gas production, as well as for those in boiler rooms using the gas. 4. Possibility of automation of complex production processes of thermal-electric powerplants using underground gas with economic installations for steam production. 5. Economic operation of thermal-electric powerplants constructed in the areas of underground-gas production. 6. Release of railroads from the burden of transporting fuel. 7. Extension of the power base of some areas in need of fuel and of the economy as a whole due to use of fuel deposits not amenable to normal mining practices. 8. Reduction of capital investments per unit of energy produced in the form of fuel. 9. Substantial increase in general labor productivity. 10. Possibility of substantial reduction in the cost of fuel produced and of electric power produced from underground gas.

Jan 1, 1962

By Virgil Marple

In the summer of 1979 the University of Minnesota Mobile Laboratory (UMML), designed for the analysis of airborne particles and gases was used to study fugitive dust from an open pit coal mine. The analysis consisted of determining the particle size distribution and concentration of dust from various mining operations, such as blasting, draglines, loading, roadways and bottom scrapers. For some operations the particles size distribution and concentrations were determined at varying distrances. Details of the dust concentration within the plumes as the plume passed the UMML were measured with an optical particle counter. For line sources, such as roadways this enabled the calculation of the particle flux at the sampling location. In addition to the standard instruments associated with the UMML, the applicability of some new instruments were investigated. These included a uniform deposit cascade impactor and a flux meter. Finally, a technique in identifying plume origins which utilized elemental X-ray flourescence analysis of filter samples was shown to be effective.

Jan 1, 1980

By Nicholas R. Dixon

This report summarizes all work performed under Phases I, II and III of U.S. Bureau of Mines Contract H0387006, "Development of a Prototype Retrofit Noise Control Treatment for Jumbo Drills." The noise and vibration levels of four jumbo drills were characterized and a survey of percussive rock drill usage is reported. A Gardner-Denver DH 123 drill was chosen as a demonstration drill, and extensive noise diagnostic studies were performed. Noise control treatments were designed, developed and evaluated in a reverberant drill test facility. The treatments consisted of an integral enclosure/muffler for the drifter, vibration isolation of the drifter from the enclosure and feed, and a drill steel sheath. A 19 dBA reduction in overall sound power level was achieved with no loss in drilling rate. The prototype retrofit treatments were field tested in an aboveground mine and in a production section of an underground zinc mine. Long-term durability and operator acceptance of the enclosure/muffler treatment were excellent. Preliminary evaluation of the drill steel sheath was encouraging, although additional testing is required.

Jan 1, 1982

By E. M. Cohn

The literature dealing with the electrical conductivity of solid dielectrics, including all its aspects and its relationships to other physical properties of these materials, is extensive and scattered in many books, phamphlets, and periodicals. It is believed that most of the important contributions to this field up to October 1943 have been listed and abstracted in this circular. Also included are some general references on static electricity. Methods of removing static charges are described; methods of and conditions for measurements of resistivity are discussed; equations for the calculation of resistivity are given; and methods of resistance measurements in Situ are reviewed. Data on the variations of resistivity with changing conditions as well as explanations for them have been collected, and three tables showing the resistivity of various dielectrics at different humidities are included. The appendix contains a short development of the mathematical formulation of the charging and discharging currents due to interfacial polarisation. INTRODUCTION Methods for Removing Static Electricity Of the various means employed for preventing or removing accumulations of static electricity in industrial processes, grounding is the most common and most generally effective. It is a precaution readily applied to stationary machines anti may often be utilized to good advantage to rid persons and portable equipment of an acquired charge. There are many situations, however, in which direct low-resistance grounding cannot be used, either because the charged bodies are insulators or are inaccessible, or because contact to a ground lead might give rise to a hazardous spark. If the charged body is a conductor, contact made to a neighboring conductor, even though the latter be insulated from ground and of relatively small capacitance, may also result in the occurrence of an incendive spark. In such instances, static electricity can sometimes be removed most satisfactorily by means of strong atmospheric ionization produced by radioactive material, X-rays, ultraviolet light, or A. C. high-voltage brush discharge. Where no danger exists from flammable

Jan 1, 1944

The objective of this handbook is to provide the inspector with guidance for recognizing hazards from inhalation contaminants in above ground work areas of underground and surface coal mining and processing facilities and evaluating these hazards by collecting samples or making field determinations and interpreting the analytical results. There are several portions of the handbook which should prove most useful to the inspectors. The names and locations of these portions are listed below: Survey Check List (Page 2-3) Rules for Determining if Sampling is Required (Page 2-1) List of Most Frequently Encountered Contaminants (Page 2-2) List of Candidate Contaminants and their Sampling Conditions (Table 2, Starting on page 2-5) Interpretation of Results (Page 2-16) Procedure for a, Health and Safety Inspection (Page 2-25) For obtaining information not available from the above mentioned portions of the handbook, the inspector is directed to the Table of Contents, the Glossary of Terms, and the List of Commercial Products Encountered in Surveys.

Jan 1, 1975

By Stephen E. Stewart

This document presents the explosion-proof enclosures used severity of certification tests solutions to linear transient thermal and stress analyses of in underground mines. The results were used to assess the for enclosure windows relative to possible loads occurring in the actual mine environment. Cast iron electric light enclosures with polycarbonate and glass windows were analyzed under steady state thermal conditions (light burning) and for thermal shocks corresponding to an internal explosion (ignition of volatile mine gas) or external quenching (mine water spray system). Thermal shocks to the enclosure, caused by ignited gases or water spray, were applied via a series of load steps in the transient analysis. The temperature dependence of material I properties and of the film heat transfer coefficients were included in the model. The work demonstrates that thermally induced stresses are strongly influenced by the way the window is mounted in the enclosure. It also shows that the MSHA Thermal Shock Test, if performed on an unsupported lens (or window), produces lower stresses than the lens (or window) may experience in the mine environment.

Jan 1, 1984

By D. J. Dollhopf

This research was part of an effort to investigate means of reestablishing non¬polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. Chemically undesirable overburden material was selectively backfilled with the intent that it would be below the future root zone, be above the reestablished aquifer, and would not be leached as a result of deep percolation. After 2 years the buried material remains above the spoil aquifer and below the maximum rooting depth. Unsaturated water flow from the land surface to the buried material occurred during wet climatological periods. No significant leaching of buried material was observed, however. Overburden sample contamination from drill stem joint grease with Pb, Zn, and Cu additives caused substantial error regarding DTPA extractable trace metals. A grease with teflon and talc additives was recommended for use in future sampling programs. DTPA extractable trace elements in overburden material had no statistical relationship to post-mine ground-water quality. Overburden columns leached with water produced leachates comparable to overburden and spoil ground-water trace metal quality. A depositional model described the Rosebud Coal overburden as a fluvial system with distinct units of sand, silt, and clay, with distinct chemical properties. Physical and chemical characteristics of the model were comparable to the in situ geochemical system, a relationship which may aid in locating overburden materials unsuitable for reclamation.

Jan 1, 1979

By Ned Baker

Details are given of a Hydride Fuel System to provide 5 kg of HZ to fuel a Caterpillar 3304 engine previously modified to operate on hydrogen fuel and intended to power an underground mining vehicle. The Fuel System was installed onto the engine and the Engine/Fuel System tested under cold start conditions and a full range of engine loads and speeds. Refueling tests were also performed. The fuel system tested will support full engine power and allow delivery of at least 3/4-power on a continuous basis, from cold start conditions.

Jan 1, 1983

By Roger M. Turpening

This study was performed to examine the feasibility of using seismic shear waves to detect the presence of abandoned coal mines. !he Antiquity Coal Mine near Antiquity, Ohio was used as a region of known voids. No attempt was made here to accurately locate the mine tunnels if detection was obtained. The results of this study were positive. Sharp changes in the amplitude of the received shear waves were clear indications of the presence of a fluid (gas or liquid) filled region between the source and receivers. When moving the source showed no change in the received signals it was concluded that the voids existed beneath the sensors. Prior to these tests drilling (SM-3) had determined that a void did exist in this area. This void was confirmed by this shear wave test and two additional voids were found.

Jan 1, 2012

By J. T. McCartney

OPTICAL PROPERTIES of U.S. coals of differing rank have been investigated by the Bureau of Mines, for about 20 years. These investigations have been remade to further the development of an objective basis for petrographic analysis of coal and to add to knowledge of the structure and composition of coal and coal components by determining their optical constants in various regions of the electromagnetic spectrum. Various experimental techniques have been used in these studies, including determination of reflectance from bulk specimens and transmittance of thin and ultrathin sections, interferometry, electron microscopy, and election diffraction. Similar studies leave also been made of graphite, the end product of coal metamorphism. The bureau of Mines conducted the first U.S. investigation of reflectance properties of coal components, laying the foundation for petrographic analysis based on arbitrary reflectance classes and for automated reflectance analysis of coals. Optical constants of coals of differing rank and of graphite have been determined in the ultraviolet-visible-near infrared spectrum. Maxima in the optical constants of graphite were observed in the ultraviolet region and were interpreted to be related to transitions of electrons between the valence and conduction bands. Similar maxima for coals, especially high-rank coals, appeared to be characteristic of the presence of graphitelike layers. A special application of optical theory to absorbing, anisotropic materials like graphite and high-rank coals has been developed. Electron microscopic and electron diffraction studies of coals have revealed various ultrafine structures in coal components and have shown the evolution of an oriented, crystalline graphite structure in high-rank coals.

Jan 1, 1967

By Piyush K. Dutta

This report describes the design, development, manufacture and incorporation of noise control features on a jumbo drill and the results of successful tests of this drill in surface and underground mines. The noise-reducing features developed under this program are applicable to future designs of jumbo mounted drills that can be cost effectively manufactured and have the potential to reduce noise levels at the operator's position from 115-120 dBA to 95 dBA or less without a reduction of currently attainable drilling rates.

Jan 1, 1985