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By R. D. Leitch

The work of the United States Bureau of Mines on stream pollution by coal-mine drainage has included a study of seasonal variations in acidity and volume of several streams in Pennsylvania. The acidity of these streams has been determined during the two or three years prior to 1930 and the results may be considered to represent "normal" low water conditions. The summer of 1330, however, was unusually dry and represents what may be termed "extreme low water conditions on these streams. This report is a comparison of the results obtained for extreme low water of 1930 and for other years. The streams investigated were Buffalo Creek in Somerset County, Indian Creek (lower 5 miles) in Westmoreland County, Little Toby Creek in Elk and Jefferson Counties, Daguscohonda Run in Elk County and West Creek in Elk and Cameron Counties. These will be treated separately in the order given. Most of the descriptive matter and physical data pertinent to the streams and drainage basins are taken from published reports of the Pennsylvania State Water Supply Commission, 1917.

Jan 1, 1931

By R. V. Ramani, V. T. Burgos, J. A. McClay

Model testing is a two part operation; first, to assure the valid¬ity of the mathematical statements and second, to evaluate the accuracy of the computer model for predictive purposes. Verification of both the conceptual and computational aspects can be achieved through the use of input data for which output results are available for comparison. In this dissertation, two test problems were selected for model testing from the Economic Evaluation Reports of the U.S. Bureau of Mines, Process Evaluation Group. Verification Data Set I Input data for this test was selected from an economic analysis of a hypothetical 1,056,000-ton-per-year mine in a 48-inch bituminous coal seam (Process Evaluation Group-Report No. 72-27, 1972). The mine was scheduled to operate five days per week, three shifts per day, 220 days per year with an estimated life of 20 years. Coal reserves covered an area of 6.4 square miles with an expected recovery rate of 70%. Production was achieved through 4 continuous miner sections with an average production rate of 400 tons per shift. The cost summary in the report included a breakdown of equipment and labor requirements. A depreciation schedule listed the expected capital expense per year of operation, assuming capital replacement with identical units and no change in the unit cost. Supply and oper¬ating costs were listed in both gross annual figures and cost per ton of production. The operating and investment costs were projected over the 20 year mine life and a discounted cash flow analysis performed to determine

Jan 1, 1975

By Alvin Kaufman

Following the gold discoveries of the late 1800's much was written regarding the vast mineral resources of Alaska, and much interest was aroused, and yet over the years little has been done to exploit those resources. Between 1906 and 1935 the Kennecott copper mines of the Copper River region were the keystone of the mineral economy (fig, 1). After the depletion of the Kennecott ore reserves and aided by the statutory rise in the price of gold, the yellow metal became the major mineral commodity. In recent years it has shared the honors with coal and sand and gravel. Although this trend should indicate the development of a stable, diversified mineral industry, yet the trend of production is downward. This report results from a study by the Federal Bureau of Mines to delineate the problems and to forecast the growth of the mineral industries in Alaska. The need for such a blueprint for the future was enhanced by the population explosion in the United States and the consequent eventual need for additional living space, as well as the current interest in new areas, and the necessity to develop reserves of strategic minerals.

Jan 1, 1961

By F. E. Armstrong

This report describes development and application by the Bureau of Mines of techniques and instruments for using radioactive inert-gas tracers to determine flow paths through petroleum reservoirs that have natural fracture systems and for which water injection has been selected as the stimulative production method. A field test was made to prove the techniques and evaluate instrumentation. The feasibility of applying the techniques and instruments to the solution of reservoir problems in other stimulative methods of production also is discussed. Oil commonly is displaced from sandstone host rocks by the action of a driving force that causes the oil to move through interstices of the rock and into production wells. In addition to the requirements of oil being trapped within the sand pores and the presence of an effective displacement mechanism, the rock itself must have adequate permeability to permit flow of oil and other fluids.

Jan 1, 1961

By Daryl R. Tweeton

The Bureau of Mines compared the effects of surface-active chemicals with those of pure water on core-drilling rock and quartz and on fracturing quartz. The objectives were to determine if these chemicals assist drilling and fracturing rock and if zeta potential control was worth pursuing as an aid to full-scale drilling. All tests were performed in the laboratory. No significant increases in drilling rates were observed for 1 to 10,000 ppm Al (as AlC13) in flushing water when drilling microcline or serpentine, nor for 1 to 10,000 ppm Mg (as MgC12) when drilling microcline or marble. Concentrations near those giving a zero zeta potential were used with microcline and marble. A 50-pct rate increase was observed for drilling quartz in 0.7 ppm oleylammonium acetate, which gave a zero zeta potential. No other concentrations were used. No effect on the tensile strength of quartz thread in 0.05 ppm Al (as AlC13), which gave a zero zeta potential, was observed. Heptanol, reported to give a zero zeta potential on quartz, did not reduce the bending strength of small quartz bars below that in water. These generally negative findings raise doubt about the usefulness of zeta potential control in full-scale drilling. The results, combined with previous studies, suggest that controlling physical properties of drilling fluids, such as viscosity, is more useful than altering chemical properties.

Jan 1, 1976

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 Donna D. Harbuck

The Bureau of Mines has investigated a process to produce titanium powder directly from titanium salts. If successful, such a process could lower the cost and increase the use of titanium. In this study, K2TiF6, K2TiF3, and TiF3 were reduced with potassium in the temperature range of 650° to 750° C. Under certain conditions, titanium powder 1.6 to 3.3 microns in size was produced. After leaching the product with a 0.1M HCl solution, powder impurities as low as 0.04 pct potassium and 0.28 pct fluorine were obtained. However, oxygen levels of over 1 pct and the frequent formation of insoluble byproducts demonstrate the need for further research to make the powder suitable for powder metallurgy applications.

Jan 1, 2011

By George C. Branner

This circular is concerned with eight nonferrous scrap metals as they generated, collected, prepared, and consumed in California. Brief reference also is included with respect to Nevada and Hawaii. Four of these scrap metals - copper, lead, aluminum, and zinc - are of major importance and make up about 95 percent of the total value, whereas the remaining four - antimony, magnesium, nickel, and tin - make up the remaining 5 percent. For convenience, the subject matter is divided into three parts, (1) Data with respect to the collection, preparation, and marketing practices that are common activities to all the nonferrous scrap metals; (2) separate discussions and statistical data with respect to each of the eight nonferrous scrap metals in California; and (3) data with respect to Nevada and Hawaii.

Jan 1, 1962

By O. C. Blade

This report on the properties of motor fuels sold through service stations in the United States was made in accordance with a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. By agreement with the American Petroleum Institute, identification of the items is confidential. It presents analytical data for 4,680 samples, representing the products of 130 companies. The samples were collected during December 1953 and January and February 1954. As in previous surveys, the gasolines covered by this survey include those from both large and small suppliers. The data were obtained by laboratories of various refiners, motor manufacturers, and chemical companies and submitted to the Bureau of Mines for compilation. A list of the National Motor-Gasoline Survey reports published during the past ten years is given on page 5.

Jan 1, 1954

By D. F. Walsh

A study of damping capacity was made on a number of magnesium-base alloys, commercial types and experimental compositions. Hardness and tensile properties were determined, and the microstructure of each alloy was examined. Alloys of low yield strength, in general, possessed high damping ability. A correlation was established between damping capacity and composition.

Jan 1, 1962

By Roy L. Grant

The Bureau of Mines investigated the up-and-down method with factorial designs to determine if shorter, and therefore less costly, trial sequences could be used. Although sequences of 50 trials are usually recommended, sequences of 20 trials were arbitrarily chosen for the experiments with permissible coal mine explosives described in this report. These explosives were fired from a cannon pointed into a flammable natural gas-air atmosphere at the Bureau of Mines Explosives Research Center gallery to ascertain their safety properties. The investigation demonstrated that the shorter sequences led to useful conclusions with a reduction in cost of the experimental program.

Jan 1, 1967

By C. C. Popoff

This report reviews the phosphate deposits, mines, and industry, and prospects in 10 districts covering most of the Montana phosphate field. These districts are discussed individually, and an evaluation of the resources and potential of each is presented. Phosphate rock produced from underground mines in the Garrison district is shipped to Canada for processing to fertilizers, utilized locally for production of animal feed supplement, and pulverized and sold for direct application to the soil. Production from the Melrose district is shipped to Silver Bow and processed to elemental phosphorus. The Maxville-Philipsburg district is destined to become a major producer with the development of the Douglas Creek mine and beneficiation plant by Montana Phosphate Products Co. Montana ranks fourth after Florida, Tennessee, and Idaho in total annual production in the United States. Production him increased from about 60,000 long tons of acid-grade phosphate rock in 1940 to more than 660,000 tons of acid-, beneficiation-, and furnace-grade ore in 1961. Montana has the second largest potential resources in the Western field; in the area south of Butte there are approximately 1.2 billion tons of phosphate rock (+18 to +31 pct P2O5) available above and within 100 feet below entry level; and in the northern part of the field there are about 67.6 million tons available above entry level. In contrast to Idaho, most of the phosphate deposits in Montana are best suited to underground mining.

Jan 1, 1965

By W. L. Dare

This paper is one of a series being prepared by the Bureau of Mines on the methods and costs of mining uranium on the Colorado Plateau. The Continental No. l mine is at the south end of the Big Indian mining district, San Juan County, Utah. The mine is on a school section owned by the State of Utah and leased by Continental Uranium, Inc. A 70,000-ton uranium-vanadium ore deposit was discovered as a result of an exploratory drilling program completed in 1954.

Jan 1, 1957

By Oliver W. Keener

This paper describing the methods and costs of mining at the Hartley-Grantham mine of the Century Zinc Co. in the Tri-State Lead and Zinc district is one of a series being prepared by the United States Bureau of Mines can mining practices, methods, and costs in the various mining districts of the United States. LOCATION, HISTORY, AND GEOLOGY The Hartley-Grantham Mine is located just outside the city limits of Baxter Springs, Kans., as shown in Figure 1. A plan of the mine is given in Figure 2, and Figure is a cross section through A - A of Figure 2.

Jan 1, 1930

By James R. Coldwell

Mining and processing cost analyses were conducted by the U.S. Bureau of Mines on stratiform zinc-lead-silver, coal, and stratiform barite deposit types that are found in the Colville Mining District. Reserves and gross revenues which would allow these deposits to be minable were modeled. A 15% Discounted cash-flow rate-of-return economic threshold was selected as the minimum acceptable return on investment for the three deposit types. The economic modeling indicated combinations of grades and tonnages for stratiform sulfide deposits that could be economically viable for orebodies ranging in size from 25 to 130 million metric tons. The gross revenues for a surface mine range from $200/mt for a 5,000 mtpd operation using the proposed South corridor to $140/mt for a 17,000 mtpd mine using the proposed North corridor. The economic modeling indicated underground coal mining was subeconomic for deposits ranging in size from 42 to 250 million metric tons. The required gross revenues ranged from $300/mt for a 2,200 mtpd mine to $21 D/mt for a 13,000 mtpd mine. The economic modeling indicated supplying projected in-state barite demand was subeconomic for the three seasonal surface mines modeled. The required gross revenues ranged from $600/mt for a 90,000 mtpy mine to $840/mt for a 6,000 mtpy mine.

Jan 1, 1995

By Richard J. Mainiero

Traditional techniques for the experimental determination of toxic fumes produced by the detonation of high explosives are not applicable to blasting agents. To detonate properly, blasting agents require confinement, a significant booster, charge diameters of 3 inches (7.5 cm) or greater, and charge lengths greater than two-times the charge diameter. Without these conditions, blasting agents will not detonate at full order, leading to a misrepresentation of the gaseous products. A facility for detonating large, confined charges in a controlled volume has been constructed at the Pittsburgh Research Center’s Experimental Mine. The facility consists of a portion of mine entry (once used for full-scale mine explosion research and demonstrations) enclosed between two explosion proof bulkheads. Total volume of the chamber is 9,666 ft (274 m). The chamber is equipped with an air circulating system and is3 3vented using the mine's airflow. Up to 10-pound (4.5-kg) charges can be detonated in the chamber using a variety of confinements. For a typical test, the blasting agent is confined in a 4-inch (10-cm) schedule 80 steel pipe and initiated by a 3-inch (7.5-cm) diameter, 1-inch (2.5-cm) thick Pentolite booster. This combination of confinement and initiation yields a detonation velocity of about 4,000 m/sec for ANFO. This velocity is in line with that measured for blasting in the field. Twenty four 2-inch thick steel plates are suspended around the pipe bomb to stop shrapnel that would otherwise seriously damage the chamber. Following detonation of an explosive in the chamber, a circulating fan is run for about 10 minutes to uniformly mix the chamber atmosphere. Fumes samples are taken out of the chamber through 1/4-inch (0.6-cm) Teflon or polyethylene2tubes for analysis. The fumes are analyzed using bubblers or Vacutainers to collect samples for analysis by the analytical chemistry lab. The technique described here has been employed to determine the fumes produced by the detonation of a variety of ANFO formulations and commercial explosives. This technique may be developed as a standard test to measure fumes produced by blasting agents or may be used to provide data with which to develop a computer model that will reliably predict the expected fumes production based on chemical composition.

By Foster Fraas

The objective of this research was separation of one highly conductive mineral from a second conductive mineral , a procedure which is impractical in commercial electrostatic separators using metal rolls . Such separators permit separation of nonconductive from conductive minerals . A new technique involved use of carrier electrode rolls specially prepared by anodizing and / or oxidizing at high temperatures to form suitable oxide surfaces . Specific oxides included aluminum , copper , and nickel . The significant result provided by the new surfaces was the extension of the separation range to higher conductivities , an extension in relative mineral conductivity from 10-14 mhos . The results are in accordance with the blocking- layer theory .

Jan 1, 1964

By T. M. Klemetti, G. M. Molinda, D. M. Pappas

Some of the most difficult coal mine roof in the U.S. can be found in the Illinois Basin. Factors contributing to the high roof fall rate include: weak moisture-sensitive roof rock, high horizontal stress, and limited longwall mining. The depth of cover ranges from 90-1,000 ft and roof damage from horizontal stress can be severe. Moisture sensitive-roof rock is common above the Springfield-Harrisburg Herrin #5 and #6 seams in the Illinois Basin, and contributes to roof skin deterioration. The roof fall rate increases significantly in the humid summer months. The National Institute for Occupational Safety and Health (NIOSH) has shown, using lab and field studies, that highly moisture-sensitive roof rock can be directly correlated to poor roof conditions. Controlling the skin is the key to reducing rock fall injuries, and roof screening is, by far, the best remedy. Illinois Basin coal operators have been successful in reducing the number of rock fall injuries in recent years. NIOSH has documented best practices for screen installation which has resulted in safe, efficient operations. Other solutions to skin failure include: the use of denser five bolts per row patterns to reduce spans between bolts, systematic supplemental support in intersections, straps and large pans protecting operators, and air conditioning to remove moisture from the intake air.

By A. J. Miscoe

A unique machine for inducing bending fatigue in wire ropes was built at the U.S. Bureau of Mines' Pittsburgh Research Center. This machine can produce nine levels of degradation through repetitive cycling of long samples of wire ropes of the types used in the mining industry. This report provides an analysis of the results of the first wire rope to be fatigued on this machine. These results have indicated that as a wire rope accumulates bending cycles, its strength first decreases because of wear and then in-creases due to cold working of the wires. As the amount of cold working increases, more and more of the embrittled wires break and the strength of the rope decreases rapidly. In this test, application of several of the regulatory retirement criteria to various sections of the rope suggests that there may be some inconsistency among them.

Jan 1, 2010

By Thomas J. Peters

During the 1982 Bureau of Mines study, 55 lode and 17 placer claims were held in the RARE II area. An estimated 150 lode claims and 50 placer claim, have been located in the study area; five were patented. There are no mineral leases. Gold has been produced from 8 lode mines and stream gravels have been worked for placer gold at 4 sites. Two suction dredges were active in stream gravels, but no significant gravel bars are identified. Identified mineral resources in the Weaver Bally area are gold and byproduct silver. The identified resources are at the Globe Mine, where approximately 33,000 tons of indicated marginal reserves (2,000 tons in the RARE II area, and 31,000 tons in the adjacent proposed Trinity Alps Wilderness) contain 0.45 oz gold per ton and probably 0.1 oz silver per ton. There are an additional 150,000 tons of inferred marginal reserves (35,000 tons in the RARE II area, and 115,000 tons in the adjacent proposed wilderness) averaging 0.38 oz gold per ton and probably 0.1 oz silver per ton. There is high potential for additional resources at the Globe Mine.

Jan 1, 1983