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By R. S. Warfield

Several reconnaissance-type surface and drill core samples of Arctic Northwestern Alaska coals were taken during the summer field seasons of 1964 and 1966 for coking studies. Surface samples were taken from the Kokolik River and the Cape Beaufort areas; core samples were obtained from the Kukpowruk River and the Cape Beaufort areas. Only one Kokolik River surface sample possessed coking properties. This sample, representing an 11.6-ft coal seam, made coke approaching metallurgical quality when a 30-pct portion of selected blending coals was added. Four Kukpowruk River core samples, each representing the same 19-to 20-ft coal seam, were all of about the same coking quality. No differences of coke quality attributable to depth of permanently frozen overburden were found, but the data confirm previously reported information that the 19- to 20-ft coal bed is a potentially satisfactory base coking coal. In the Cape Beaufort area, a core sample with appreciable coking properties was taken at depth from a coalbed determined noncoking in a surface sample.

Jan 1, 1969

By Secretary of the Interior

"INTRODUCTION The Bureau of Mines Synthetic Liquid Fuels Program again forged ahead during 1952, and important technical advances led the way to improved methods of converting coal and oil shale into liquid fuels. Marking the eighth year of activities under this program, the pact 32 months brought a new domestic industry nearer realization.The increasing demand for gasoline and oil and the rising cost of finding new petroleum, coupled with America's growing dependence on imports and the unsettled international situation, have continued to emphasize the importance of the Bureau's Synthetic Liquid Fuels Program. Oil, the indispensable material of wartime, likewise has critical importance in peacetime, touching as it does the life of every individual. Supplementing petroleum with synthetic liquid fuels will not only conserve this Nation's petroleum reserves but also will bring into greater use its tremendous reserves of coal, as well as the vast deposits of oil shale for which no other practical use has yet been found.The Bureau of Mines Synthetic Liquid Fuels Program is one of the most important and far-reaching of the Government's research projects. Through development of commercial synthetic liquid fuels, the United States can obtain oil products from its great inland reserves of coal and oil shale to supplement petroleum in any quantity that may be necessary, consistent with economic and other requirements, such as national defense. The use of raw materials from such deposits would be of highest importance in wartime, when shipping lanes are menaced by the enemy. The Synthetic Liquid Fuels Program of the Bureau of Mines and research efforts of industry have advanced. American technology to the point where it is now possible to begin the design and construction of prototype plants. Certainly, significant improvements will be made as the program continues, but this prospect in no way alters the fact that the start of prototype plants should be encouraged. These plants, as the first step in the development of a synthetic fuels industry, would serve a threefold purpose:"

Jan 1, 1953

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

Jan 1, 1954

By M. P. Hardy

Copper-Nickel ores in northeastern Minnesota could establish a new industry in a region where underground mining has not been active. This study reviews geotechnical data relevant to the selection and design of underground mines in this region and by numerical structural analysis evaluates the importance of some geotechnical parameters to mine method selection. Because of the rapid development of computer modeling many new techniques have become available for modeling rock mass behavior in recent years. An overview of these methods is presented and their applicability to mine design reviewed. Methods included in this summary were the differential continuum models, such as finite Pint and finite difference, integral continuum models, such as boundary element, displacement discontinuity and boundary integral equation methods, and discontinuum methods such as the distinct block model. The displacement discontinuity method was used to evaluate the influence of geotechnical parameters on some aspects of mine design. Three problems; room stability, pillar stability on a weak inclined contact and sill pillar thickness influence on sill pillar stability, were analyzed to evaluate the relative importance of insitu stress field and joint properties on design. It was concluded that for stability analysis the initial horizontal stress is of most importance in all aspects of design. The position, orientation, persistence and strength of joints is also of primary concern. In a more general sense, however, it was concluded that detailed geotechnical parameters have much less influence on mine method selection than more general factors such as rock quality, initial stress state, orebody shape and economics.

Jan 1, 1978

By S. R. Crane

One Bureau of Mines goal is to minimize the undesirable environmental impacts associated with industrial plants emitting waste gases containing S02. To help meet this goal, a regenerable flue gas desulfurization process was developed. This process, known as the citrate process, uses a buffered weak acid solution to absorb S02 from the waste gas. The absorbed S02 is reacted with H2S to precipitate elemental sulfur and regenerate the solution for recycle. The H2S feedstock for the process, if not otherwise available, may be produced by reacting two-thirds of the recovered elemental sulfur with natural gas and steam. Laboratory investigations and pilot plant operations were conducted by the Bureau to determine if H2S from the natural gas, sulfur, and steam reaction was suitable for the citrate process. The laboratory investigations, in which an H2S generator was integrated with other citrate process operations, provided a basis for design and operation of the pilot plant. The objective of the pilot plant was primarily to provide H2S for the citrate pro-cess pilot plant at the Bunker Hill Co. lead smelter in Kellogg, Idaho. The design capacity of the pilot plant was 0.4 to 1.25 tons of H2S per day. The operation demonstrated that (1) a 77-to 79-dry-volume-percent H2S product could be produced from pilot-plant product sulfur, natural gas, and steam; (2) the product R2S regenerated the SO2-loaded citrate solution; and (3) under certain conditions over 95 percent of the natural gas could be converted to H2S.

Jan 1, 1981

By Andrew M. Leszcykowski

In 1985, at the request of the Bureau of Land Management, personnel from the U.S. Bureau of Mines examined 18,700 acres of the 24,922-acre Eighteen Mile Wilderness Study Area to evaluate mineral resources. This study area is in east-central Idaho in Lemhi County, approximately 20 miles southeast of Leadore. The study area is underlain by Paleozoic marine sedimentary rock and Ordovician granitic rock. The sedimentary rock is primarily limestone and dolomite with a minor amount of siltstone. The Nicholia mining district borders the southern boundary of the study area. However, none of the district's mineral-bearing structures appear to trend into the study area. Just outside the northwestern part of the study area, on Clear Creek, is the E. J. Wilson and Sons? open-pit gypsum mine that operated until about 1977. About 120,000 tons of gypsum were produced from the mine for the cement plant at Inkom, ID, and for use as soil conditioner. Two theories for the origin of gypsum deposits are a hydrothermal source and a stratabound occurrence. Hydrothermal deposition is favored for this deposit. Occurrences of gypsum may exist in the study area. However, known reserves are adequate to meet needs for at least 800 years. There are no known mines, claims, or leases in the study area. INTRODUCTION This report describes the USBM (U.S. Bureau of Mines) portion of a cooperative study with the USGS (U.S. Geological Survey) to evaluate mineral resources and potential of part of the Eighteen Mile WSA (Wilderness Study Area) 1/ at the request of the Bureau of Land Management (BLM). The USBM examines and evaluates individual mines, prospects, claims, and mineralized zones, and evaluates identified mineral and energy resources. The USGS evaluates potential for undiscovered resources based on areal geological, geochemical, and geophysical surveys. Results of the investigations will be used to help determine the suitability of the study area for inclusion into the National Wilderness Preservation System. The immediate goal of this and other USBM mineral surveys is to provide data for the President, Congress, government agencies, and the public for land-use decisions. The long-term objective is to ensure the Nation has an adequate and dependable supply of minerals at a reasonable cost.

Jan 1, 1986

By William C. Cooley

This study Identifies and evaluates deposits of noncoal minerals in the U.S. which are most amenable to be mined underground hydraulically and transported hydraulically. A method was developed to screen and compare mineral deposits including economic comparisons. The most applicable minerals for hydraulic mining by borehole monitor jets from underground entries are soft uranium sandstones In Wyoming in locations where water is available. This method with hydrotransport could improve the safety, health and economy of underground uranium mining. Soft oil-bearing sandstones in California and Texas could be mined and transported by this method more safely than by other underground mining methods. Other weak sandstones may be hydraulically mined economically. Man, minerals are too hard to be mined by monitor jet but are amenable to hydraulic transport and hoisting. Uranium sandstone in New Mexico is of interest because of potentially improved health and safety in transport and lower transport cost, Increases in mine output for potash, in New Mexico and trona in Wyoming can be achieved most economically by adding hydraulic hoisting when existing skip capacity is at its limit. Research is recommended to obtain site-specific data on the feasibility of mining uranium ores by monitor jets.

Jan 1, 1981

By Richard H. Bares

This report describes the purpose and application of seventeen statistical and mathematical procedures used in a series of studies made in the project ?A Systems Approach to the Reclamation of Strip-Mined Areas in North Dakota". The objective is to help readers better understand the utility of these procedures.

Jan 1, 1982

By A. Monomakhoff

If a conductor traversed by an electric current is broken, a conduction forms in the air between the two broken ends of the wire. This conduction manifests itself in an initial phase by an electric spark and, in a second phase, by an arc if the the circuit continues to supply sufficient power. This arc goes out when the distance between the two ends of the conductor becomes sufficiently large. If the break occurs in an explosive atmosphere, the energy contributed by the arc can cause an explosion. To avoid such accidents, electric circuits that may be utilized in hazardous atmospheres can be made "intrinsically safe". The investigation which we conducted is part of a research project on the intrinsic safety of arcs of high intensity but short duration, in the case of resistive circuits. We developed an electronic system which makes it possible to limit the duration of an arc at the level of the break of a conductor traversed by a current with a possible maximum intensity of 80 amperes. This experimental device for monitoring and measuring the parameters of the arc has shown that arcs of high intensity but with a duration limited to a few microseconds do not ignite an explosive methane-air mixture.

Jan 1, 1975

By Harry W. Campbell

A mineral survey conducted by the U.S. Bureau of Mines in 1983 identified no mineral resources in the Beaver Meadows, Blind Horse Creek, Chute Mountain, Deep Creek/Battle Creek, and North Fork of Sun River Wilderness Study Areas (WSA's). A prospect east of the Beaver Meadows WSA has low potential for lead resources. Sand, gravel, and limestone occurrences are numerous in the WSA's; however, similar or better quality materials outside the areas are abundant and more accessible to potential markets. Impure coal and titaniferous-magnetite occurrences are near the WSA's, but are not known to occur within these areas. In 1983, there were 7,025 acres leased for oil and gas within the five WSA's; no current mining claims were in or near any of the WSA's. Evidence of mining activity was found at only one prospect in the WSA's. It is inside the Deep Creek/Battle Creek WSA; no resources or resource potential were identified at this prospect.

Jan 1, 1984

By Jerome Apt

This report presents the methods and results performed pursuant to the U. S. Bureau of Mines contract entitled "Noise Abatement in Mining Machinery," Number H0122054. 2.1 Background Until the Congress of the United States created and passed Public Law 91-173, the Federal Coal Mine Health and Safety Act of 1969, there were no directly-applicable standards for noise exposure for underground coal miners.1 Section 206 of this law, approved December 30, 1969, provided for standards of noise to be applicable to each coal mine. It is as follows:

Jan 1, 1975

By G. W. Jones

One of the major activities of the Bureau of Mines is the promotion of safety in mining and other industries, In this connection, the Bureau determines the explosion hazards' of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. Many dangers are likely to confront men who must enter a building immediately after it has been damaged. Rescue workers must watch constantly for common gases and vapors that may be present in dangerous concentrations in and about demolished, buildings. Fuel gas is the most common source of danger, although refrigerants, gases from furnaces, flues, fires, sewers, and industrial processes, and gas from bomb, explosions in confined places also constitute definite hazards. To rescuers and trapped casualties, these gases offer the hazards of (1) explosion, (2) toxic effects, including asphyxiation and death, and (3) displacement of air so that the oxygen content of the atmosphere is reduced to or below the danger level.

Jan 1, 1944

By P. G. Pigott

The lack of technical information regarding the physical characteristics of kaolins and bauxitic kaolins, rejected during the mining of bauxite near Eufaula, Ala., has retarded their commercial utilization. This investigation was undertaken to determine their behavior when used in refractories. Ores were evaluated as refractory raw materials by compounding dry-press mixtures and specialties following procedures common to the industry. Products now on the market were used for comparison in laboratory evaluation.

Jan 1, 1959

Mining activity during 1977 was limited to the production of limestone, marl, and sand and gravel, all of which were used domestically. Public works projects consumed the major portion of the construction material produced. The consortium of oil companies operating as Esso Ventures Inc., drilled one exploratory well off the coast of southern Belize. For drilling the well, Exxon Corp. received a 57% working interest in the consortium's concession located 40 kilometers east of Puta Gorda. No other offshore drilling was attempted in 1977. Esso also drilled a well on the Anschutz Overseas Inc. concession in the Toledo District of south- eastern Belize. The attempt wee abandoned, but seismic activities continued.

Jan 1, 1981

By Thomas V. Falkie

The purpose of this work was to investigate the rate at which coal is delivered from the underground working face by gathering arm type loaders as employed on continuous mining machines, to identify the factors -- geometrical, geological, mechanical, or procedural which affect the delivery rate, and to develop quantitative rate descriptive equations for the loading function. The mathematical techniques employed were factor analysis and multiple linear regression. It was determined that the coal-cutting function of the continuous mining machine is the factor that primarily influences the loading function. The geometrical factors -- the dimensions of the work area in relation to the dimensions of the mining machine - were the factors of secondary influence. Fifty-five percent of the experimental variation in the loading function was explained in terms of the six most prominent independent variables. It is expected that this work will be useful in operations-research studies as applied to underground coal mining, and with refinement will enable mine planners to select equipment based on the operating characteristics of the equipment and the mining conditions.

Jan 1, 1972

By John F. McCoy

The United States Bureau of Mines (USBM) awarded a contract to Foster-Miller Associates, Inc. (FMA) to develop guidelines for designing, constructing, stocking and maintaining rescue chambers in underground mines. This report develops information and recommendations which could be used by a mine operator who desired to install a rescue chamber. Volume I covers the following major areas: atmospheric life support, configuration and construction, chamber location, power and lighting, equipment and supplies, communications, and psychological aspects and training. Volume II contains the following appendices: History of Barricading, Chamber Pressurization Considerations, Diffusional Infiltration of Gas, Compressed Air Storage, Location Examples, and Psychological Aspects.

Jan 1, 1983

The small-scale surface mining operation in northern regions is typically located in a remote, ungaged basin. With the recent increase in the economic potential of mining, the number of small operations is increasing. The year-to-year variability in precipitation in this region under study is of great concern to mine operators. Some years may yield only 5 to 6 inches of precipitation, while others may yield in excess of 15 inches. Such variability makes placer mining operations difficult to plan, since low water years may result in too little run-off for gravel washing and high water years may result in flooding of mining developments. There are no official streamfloaw records in many watersheds in the northern region containing placer mining claims. However, information from other streams permits calculation of an estimated discharge for a watershed under consideration using average flows per square mile of drainage. It is to be emphasized that these are average or expected figures in reality, one water year may be significantly wetter or drier than another. This high variability of annual precipitation is significant in relation to placer operations because of the large quantities of water required for this type of mining. Some operations can not operate in low water years. In the larger watersheds, operations may continue in low water years but at a slower pace because of longer water collecting times. The high variability of available run-off rakes placer mining in many parts of Alaska difficult to plan on a long range because of the unpredictability of water supplies.

Jan 1, 1985

By K. B. Higbie

The quantitative separation of tantalum from columbium has been obtained through several liquid-liquid extraction processes. The valuable metals are separated by selective extraction from organic feed solution using a mineral acid or by selective extraction from aqueous feed solutions employing an organic solvent. The greatest degree of separation was obtained when organic ketones, particularly methyl isobutyl ketone, were used. Approximately 200 combinations of various organic solvents and mineral acids were tested as possible separation systems in which the tantalum or columbium content was extracted from organic solutions of the anhydrous pentachlorides.

Jan 1, 1956

The following pages discuss the objectives, the background, and scope of work of an industrial engineering analysis of far-,n haulage systems in underground retreat coal mining. This study ran concurrently with an existing industrial engineering study of methods of improving safety and production efficiency in underground pillar extraction. 1. OBJECTIVES The objective of this project was to provide basic data inputs that will inpart knowledge as to the major constraint to pillar extraction sections. Furthermore, the industrial engineering study will suggest ways to optimize haulage systems and to develop more efficient work practices and operational techniques that will maximize equipment utilization.

Jan 1, 1975

By Leslie S. Rubin

A ventilated helical boost pump was developed that can handle varying flow rates and/or solids concentrations while operating at a single rotational speed and without computer assisted feedback controls. The boost pump developed and briefly tested during this program was designed to accomodate flows suitable for a 3-in. diameter pipeline. The boost pump's ventilated design provides the automatic pressure regulation needed to meet the system's requirements for supporting transient pipeline flow.

Jan 1, 1984