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To address the safety of programmable electronics-based mining systems before this technology proliferates in the mining industry.

Jan 1, 1999

By Susan M. Moore

According to the Mine Safety and Health Administration (MSHA) injury database, 227 knee injuries were reported in underground coal mining in 2007 [ 1]. Low-seam coal mines are those with extremely low working heights (<42?). Gallagher et. al [2] found that the average cost per knee injury in low-seam coal operations was $13,121.29. Thus, it can be estimated that the financial burden of knee injuries was nearly three million dollars in 2007. Pressure applied to the knee while kneeling and crawling is likely a risk factor. Typically, mine workers utilize kneepads to better distribute the pressures at the knee; however, their ability to reduce the stresses at the knee is unknown. The objective of this study was to determine the pressure applied to the knee during static postures used in low-seam mining while not wearing kneepads and while wearing two kneepads commonly used in the industry (one articulated and one non-articulated).

Jan 1, 2009

By E. P. Youngman

A new mining law for the Recublic of Polend was promulgated by presiden- tial decree dated November 29, 1930, published in the Journal of Lews (Dzienni stex) No. E, text 654, December E, 1530, and wes to become effective January 1, 1932, in all Polend except Silesie. Its adoption in Silesia wes dependent pon the action of the Silesian Diet. As the new law is considered an im- provement over the old Austrian Mining Lew, which is operative in the Silesian districts of Bielsk and Cieszyn, and the Prussian Kining Law, which is opera- tive in Upper Silesia, no delay in its adoption for Silesin was looked for. This new law codifies the various juridical regulations pertaining to ines existing in different parts of the Polish Republic but does not include legislation with respect to the extraction of minerel oil, especially crude oil. Petroleum legislation was postponed to a later date in order to facili- tate codification in other fields. Koreover, as the oil industry exists in Galicia elone, deley will not be detrimental.

May 1, 1932

By T. L. Joseph

The size and accessibility of the Minnesota manganiferous iron ore deposits make them attractive as a potential source of erromanganese, which is essential in the production of steel. For several years the Bureau of Mines has been conducting experiments to determine the feasibility of producing ferromanganese from these ores by a three-step process which involves (1) the smelting of the ores in the blast furnaoe to produce a high-phosphorus spiegel; (2) the treatment of the spiegel produced from step 1 in an electric or open-hearth furnace to separate the manganese from the phosphorus and the iron; and 3) the smelting of the high-manganese slag from step 2 to produce forromanganese. The details of the first two steps of the process and the results of tests with the experimental furnaces Lave been given in previous reports.5 The m$ or part of the experimental work on the second step has been conducted in a half-ton open-hearth furnace. Some preliminary tests showed, however, that the electric furnace has some distinct advantages over the open hearth for producing, from high-phosphorus spiegel, a slag containing from 45 to 55 per cent manganese and phosphorus and iron in amounts required for ferro-grade ore. The electric furnace tests described in this paper were made to get more information as to the possibilities of the electric furnace in connection with this problem and to study the fluxing effect of alumina on high-manganese slags. Herty, Conley, and Royer have reported&apos; results of laboratory tests which showed that slags containing from 60 to 75 per cent MnO, from 8 to 10 per cent S102, and small amounts of CaO MgO, and FeO, were sufficiently fluid at 1,450° to 1,550° C. to pour readily if 12 to 14 per cent alumina was present. With a normal A1203 content resulting from the A1203 in the

Jan 1, 1931

By Lee Blackman

The Malheur-Jordan Resource Areas (MJRA?s) is a tract of approximately 6.5 million acres of federal and non-federal land in the southeast corner of Oregon. This study evaluated the Resource Areas&apos; economically recoverable mineral potential based on geological estimates provided in the USGS report (Smith, 1994). The mineral terranes are believed by geologists to contain undiscovered resources. The geological data is probabilistic; with estimates of the possible number of deposits and their grades and tonnages. Possible future development scenarios range from no development to numerous mines. Based on the analysis performed on these terranes, the most likely (in a statistical sense) future scenario for the resource areas would include the potential for two medium sized, predominately gold, mines. These would supply direct and indirect employment of up to about a thousand workers.

Jan 1, 1995

By A. D. Bauer

For several years the Bureau of Mines has conducted surveys to determine the changes in motor gasoline being sold throughout the United States. The present survey shows that far the districts in which samples were collected, the average gasoline is becoming more volatile instead of less so, as is sometimes supposed. This year&apos;s gasoline is much more volatile than that sold two years ago, and it has a somewhat better distillation range than last summer&apos;s samples. A comparison of the average figures for several years, shows that motor gasoline is also becoming more uniform in character. The large seasonal change is disappearing, but ?winter gasoline&apos;, still has a lower initial boiling point than "scanner gasoline". This difference in volatility is made intentionally to facilitate starting the motor in cold weather. The end point shown in the present survey is slightly lower either than that of last winter or of the summer of 1921.

Jan 1, 1922

By John Dixon

This paper is one of a series on milling methods and costs being published by the Bureau of Mines. Acknowledgment is made to J. B. Tyrrell, managing director, and Wm. Sixt, manager of the Kirkland Lake Gold Mines, for permission to publish this article. The Kirkland Lake Geld Mining Co.&apos;s mill is located on Government Road at the west end of the productive part of the Kirkland Lake mining area, 1 mile west of the village of Kirkland Lake. The crushing plant is connected to the shaft house of No. 2 shaft, which is now the only operating shaft.

Jan 1, 1931

By H. Kenworthy

The investigations described in this report were undertaken to demonstrate, on a laboratory scale, the possibility of recovering several million pounds of tin plus tungsten contained in stockpiled and currently rejected slags from the Longhorn tin smelter at Texas City, Tex. At the same time, it was anticipated that the treatment procedures developed might be applicable to slags from other tin-smelting operations. Results of the laboratory work show that it is possible, by pyrometallurgical means, to separate the tin and tungsten into products of intermediate grade that may be returned to the smelter circuits for further upgrading. Several methods of treatment were investigated. The methods that proved effective were: Fusion reduction, chloride volatilization, sulfide volatilization, and carbide formation. Over 90 percent of the tin and tungsten could be removed from the slat by any of these methods. Each type of treatment has advantages and disadvantages, and it could not be determined from the small-scale work which method was the more meritorious. Tungsten and (in some types of treatment) tin-bearing products were diluted by iron, the separation of which will require additional studies. Prevention of a portion of the iron from reporting with the tin or tungsten is a distinct advantage and possibility that will require inure laboratory work to develop the needed techniques for its accomplishment. Tin products from single treatments of stag ranged up to 75 percent in tin content but were more generally under 35 percent. Tungsten products were usually under 15 percent; but segregated portions could be selected, at a sacrifice in recovery, that contained up to 50 percent tungstic oxide equivalent.

Jan 1, 1957

By Kevin Ashley

Because toxicities may differ for Cr(VI) compounds of varying solubility, some countries and organizations have promulgated different occupational exposure limits (OELs) for soluble and insoluble hexavalent chromium (Cr(VI)) compounds, and analytical methods are needed to determine these species in workplace air samples. To address this need, international standard methods ASTM D6832 and ISO 16740 have been published that describe sequential extraction techniques for soluble and insoluble Cr(VI) in samples collected from occupational settings. However, no published performance data were previously available for these Cr(VI) sequential extraction procedures. In this work, the sequential extraction methods outlined in the relevant international standards were investigated. The procedures tested involved the use of either deionized water or an ammonium sulfate/ ammonium hydroxide buffer solution to target soluble Cr(VI) species. This was followed by extraction in a sodium carbonate/sodium hydroxide buffer solution to dissolve insoluble Cr(VI) compounds. Three-step sequential extraction with (1) water, (2) sulfate buffer and (3) carbonate buffer was also investigated. Sequential extractions were carried out on spiked samples of soluble, sparingly soluble and insoluble Cr(VI) compounds, and analyses were then generally carried out by using the diphenylcarbazide method. Similar experiments were performed on paint pigment samples and on airborne particulate ?lter samples collected from stainless steel welding. Potential interferences from soluble and insoluble Cr(III) compounds, as well as from Fe(II), were investigated. Interferences from Cr(III) species were generally absent, while the presence of Fe(II) resulted in low Cr(VI) recoveries. Two-step sequential extraction of spiked samples with (?rst) either water or sulfate buffer, and then carbonate buffer, yielded quantitative recoveries of soluble Cr(VI) and insoluble Cr(VI), respectively. Three-step sequential extraction gave excessively high recoveries of soluble Cr(VI), low recoveries of sparingly soluble Cr(VI), and quantitative recoveries of insoluble Cr(VI). Experiments on paint pigment samples using two-step extraction with water and carbonate buffer yielded varying percentages of relative fractions of soluble and insoluble Cr(VI). Sequential extractions of stainless steel welding fume air ?lter samples demonstrated the predominance of soluble Cr(VI) compounds in such samples. The performance data obtained in this work support the Cr(VI) sequential extraction procedures described in the international standards.

Jan 1, 2009

By J. C. Franklin

A 32-channel continuous monitoring system has been developed to monitor radiation working level (WL), fan operation, and air door position. The system consists of a surface receiver unit and an underground transmitter that is connected to the various monitors. A continuous WL monitor used with the system can generate alarms at two different WL readings. One of these levels is variable from 0.00 to 0.99 WL and generates an alarm on the surface receiver. The other level, fixed at 1.0 WL, generates an underground alarm in the vicinity of the monitor. The detectors for fan operation and air door position work on the principle of a completed circuit to the underground transmitter (multiplexer). When the circuit is broken, as is the case when a fan is off or an air door is open, an alarm is generated at the surface receiver. This alarm remains in effect until the circuit is completed, signifying the fan has been turned on or the air door has been closed.

Jan 1, 1982

By J. H. Wiggins

"The tests described below were conducted by the Bureau of Mines at a lease in Oklahoma on installations designed to decrease evaporation losses of crude oil Pram storage tanks. Use of the lease was granted by the Oklahoma Producing and Refining Corporation of America. Tankage was obtained through the courtesy of the Parkensburg Pig and Reel Co. The purpose of the installations and tests was to demonstrate the value of making crude-oil storage tanks gas-tight, rather than to determine the amount of evaporation in any one type of tank. None of the tanks used were absolutely gas-tight, but one of them was very nearly so. They comprised a tank of the ordinary open type with an 18-inch manhole, a tank with a ""4-inch vent"", a tank with a ""smaller vent"", and a tank which had only ""pin holes"" through which air and vapor could pass freely. On the last two tanks any excess pressure was taken care of by an automatic differential pressure regulator.The results obtained in these tests indicate that tight tankage will soon pay for itself. They will not, however, serve as a basis on which a producer can compute the actual number of days necessary for tight tankage to pay out, because the oil used was exceptionally volatile. It is probable that the average evaporation loss in the Mid-Continent field is at least one-half as great as that shown by these tests, and if this is true, the saving that would be effected by providing tight tankage on the lease will undoubtedly justify the expense. The installation of evaporation-proof tanks on the lease has been delayed by the failure of production managers to realize, first, that their evaporation losses are enormous, and, second, that they can practically eliminate these losses by a simple and inexpensive installation."

Apr 1, 1921

By R. J. Bielicki

A sorption apparatus for measuring the equilibrium sorption isotherm and the rate of diffusion of methane from fine-sized coal was designed and constructed. Preliminary work that used Pittsburgh and Pocahontas No. 3 coal shows that the diffusion coefficient varies with pressure and that the fracture spacing in these two coals is substantially different.

Jan 1, 1972

By Thomas J. Peters

In 1987, at the request of the U.S. Bureau of Land Management, the Bureau of Mines studied the 350-acre Henry?s Lake Wilderness Study Area (ID-035-077) in order to evaluate its identified mineral resources. The Wilderness Study Area is located in northern Fremont County, ID, approximately 140 air miles north-northeast of Pocatello and 3 miles south of the Montana border. The Wilderness Study Area is near the north shore of Henry&apos;s Lake at the foot of the southwest-facing slope of Black Mountain. Archean hornblende gneiss, the main rock type present, crops out northeast of the Madison Range Fault, which trends northwest across the southwest corner of the Wilderness Study Area.

Jan 1, 1988

By P. J. Colbassani

Samples of mine atmospheres collected by Federal coal-mine inspectors during their inspections and investigations of coal mines, in accordance with provisions of the Federal Coal Mine Safety Act (66 Stat. 692; 30 U. S. C., sees. 451-483) are analyzed routinely by chemical methods at Bureau of Mines laboratories. When samples collected in open workings of nongassy coal mines at points not less than 12 inches from the roof, face, or rib contain 0.25 percent or more methane, the act requires the operator, during operation of such mine, to comply with the provisions of sec. 209, Title II, of the act, which pertain to gassy mines. The methane con-tents of such samples are determined by a physical method based on infrared absorption spectrometry to provide an independent check on analytical results obtained by chemical methods. This information circular describes the equipment and procedures used by the Bureau for determining low concentrations of methane in coal mine atmospheres by infrared absorption spectrometry. ACKNOWLEDGMENTS The authors are indebted to Dr. R. A. Friedel, Chief of Spectrometric Section, Branch of Coal-to-Oil Research, Bureau of Mines, for suggesting the analytical method and for furnishing valuable advice and assistance, and to J. A. Queiser of his staff for making exploratory measurements by this method; to Dr. M. G. Zabetakis of the Division of Explosives Technology for his assistance during the conduct of preliminary experimentation; and to L. B. Berger, Chief, Branch of Health Research, under whose guidance the equipment was procured and the work conducted.

Jan 1, 1958

By William Cochran

The mineral waste disposal system at the Grace Mine, Morgantown, Pa., was designed to minimize environmental effects while allowing much of the waste from the iron mine, mill, and concentrator to be utilized. Standard cost estimating procedures were used by the Bureau of Mines to determine waste disposal costs. Mill tailings and rock waste disposal costs were estimated at $0.151 and $0.276 per ton, respectively, for the 1965-67 production period. Total waste disposal cost was reduced about $0.015 per ton by utilizing part of the waste as aggregate. The net average cost for disposal of all mineral waste was $0.189 per ton.

Jan 1, 1969

By James R. McVey

Tests during pillar robbing, longwall operations, and other mining activities indicate that roof-floor convergence rates can be used as an indicator of imminent roof failure. A large number of electrical-mechanical devices have been built to measure convergence as well as convergence rates, but most obstruct mine traffic and are costly and time consuming to install. The Bureau of Mines has designed and is evaluating three types of small ultrasonic units to make these measurements. The new instruments provide nonobstructing measurements up to 35 ft away. The ultrasonic transducers can be attached to a roof bolt, placed in an unsupported area (by means of a toss basket), or handheld. Total distance to the target and rate of closure are displayed digitally to 0.001 ft and 0.01 ft/min, respectively.

Jan 1, 1984

By W. H. Eddy

The Bureau of Mines made small-scale continuous tests and large-scale commercial plant tests of a calcareous fluorspar ore near Cave-In-Rock, Ill., to determine if the application of the lignin-fluoride process of fluorspar flotation would be industrially feasible for treatment of fluorspar ores, and also to compare the lignin-fluoride process with the quebracho process, which is the method currently used for concentrating calcareous fluorspar ores. The small-scale continuous tests yielded fluorspar concentrates analyzing 93.6 percent CaF2 with a recovery of 87.6 percent of the total fluorspar in the ore. In large-scale commercial plant tests, a fluorspar concentrate analyzing 93.3 percent CaF2 with a recovery of 78.0 percent was produced by the quebracho method. About 86.0 percent of the fluorspar was recovered in a metallurgical-grade fluorspar concentrate from the lignin-fluoride circuit which analyzed 89.9 percent CaF2? with a much simpler flowsheet than that in the current commercial application.

Jan 1, 1967

By John L. Dahle

This report documents the research efforts that were undertaken to design, install and test noise abatement devices for use on off-highway haul trucks operating in surface mines. The objective of the program was to reduce the environmental noise from haul trucks. The noise reduction devices that were developed utilized existing technology and were tested on a 50-ton haul truck. The efforts emphasized the reduction of noise emitted from the engine compartment which included the use of side shields, sound absorbing material, improved radiator shroud design, and a modulating clutch fan. Noise tests were conducted using modified SAE test procedures for measuring sound levels around a stationary and moving machine, and inside of the operators compartment. Test results showed a maximum of 4 dB(A) reduction measured 16 feet from the truck. Interior cab noise was reduced 6 dB(A) with the windows and vents closed.

Jan 1, 1983

By D. H. Platt

Bauxite, the principal source of aluminum, has been mined from deposits in Saline and Pulaski Counties, Ark., since 1899; war needs have greatly stimulated production. Many of the ore deposits are basin-shaped and either outcrop or are covered by a shallow-depth overburden at their peripheries; these are mined by stripping and open-pit methods. When stripping becomes economically impracticable, incline shafts or slopes are sunk on the dips of the deposits, and underground mining is done on the retreat, using a room-and-pillar method.

Jan 1, 1945

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

The standard method of employing preliminary air-drying to determine the moisture in coal has been criticized with respect to the loss of heating value from excessive air-drying. By this method, the coal is air-dried at approximately 10-15° above room temperature with the loss in weight being less than 0.1 percent per hour, and then the residual moisture at 105°C is determined. The total moisture is calculated from these two values.

Feb 1, 1948