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By L. J. Froisland

The Bureau of Mines conducted a 4-year research program at Uravan, Colo., on a 2-1/2-acre reclamation plot on the slope of a uranium tailings pile that had been covered with mine waste rock. The purpose of this study was to determine the effects of plant species, type of irrigation, type of fertilizers, and use of dust control chemicals on plant growth and surface coverage. Best grass coverage, nearly 100 percent with 240 plants per square foot, was developed in a section that was seeded with crested wheatgrass, fertilized with sewage sludge, and sprinkler irrigated. For comparison, a section that had been treated with commercial fertilizers developed 3.1 crested wheatgrass plants per square foot and 24 percent coverage without irrigation, and 8 plants per square foot and 75 percent coverage with irrigation. Results of spraying a dust control chemical were inconclusive. Russian-thistle invaded all test sections and ranged in density from 0.6 to 7.3 plants per square foot.

Jan 1, 1982

By Alan G. Mayton

Exposure to whole-body vibration (WBV) and the postural requirements of the job have been identified as important risk factors in the development of musculoskeletal disorders of the back among workers exposed to a vibratory environment. This paper focuses on preliminary results of WBV data collected for two groups of haulage trucks ? four older trucks from manufacturer A (MFR-A) and two newer trucks from manufacturer B (MFR-B). All of the trucks and their respective seats were considered to be in good working order during the study. Measurement periods for the truck groups had similarities, but varied from 2 to 58 minutes. Sampling times for the older trucks included a mean of 19.5 minutes and a standard deviation (STD) of 6.5 minutes compared to a mean of 40.8 minutes and a STD of 12.1 minutes for the newer trucks. Data collection coincided with the approximate delivery and first operation of the new trucks, and occurred approximately 12 months apart under similar weather and road conditions, and with the same drivers except an additional driver was included with the older trucks. Truck routes were somewhat different in that quarry production had changed location in the time between data collection activities. Overall, the results suggest that the newer trucks may provide better overall isolation to drivers/operators from WBV exposure compared to the older trucks operating at the quarry; although, this will need to be confirmed with additional measurements. Considering the higher variability and shorter sampling times for the older trucks, the results should be viewed with caution. For two of seven trials, the older trucks showed that seats amplified vibration, i.e., a transmissibility (T) >1.0. Seat T for the older trucks ranged from 0.31 to 1.17 with a mean of 0.77 and STD of 0.32. This contrasted with the newer haulage trucks where seats amplified vibration in 3 of 8 trials. In this case, T did not vary greatly and ranged from 0.87 to 1.05 with a mean of 0.97 and STD of 0.07. Regarding older trucks, in five of seven trials, the seat (output) data of weighted root-mean square (RMS) acceleration (wRMSZ) for the dominant z-axis exceeded the action level of 0.5 m/s2 action level recommended by the European Union Good Practice Guide for WBV (EUGPG) and levels exceeded the recommended exposure limit of 1.15 m/s2 in two of the seven trials. The wRMSZ values for the older trucks varied from 0.41 to 1.83 m/s2 with a mean of 0.99 and STD of 0.57. Similarly, newer trucks indicated a narrower range of wRMSZ from 0.38 to 0.95 m/s2. The mean wRMSZ was lower for the newer trucks at 0.58 m/s2 with a STD of 0.23 m/s2. Similarly, newer trucks indicated wRMSZ reached or exceeded the action level in four of eight trials. None of the trials with the new trucks showed wRMSZ levels that reached or exceeded the recommended 1.15 m/s2 exposure limit. As an indicator of driver/operator discomfort, overall weighted total RMS acceleration (vector sum) values seem to show a ?rougher? ride for the older trucks. The vector sum values for these trucks ranged widely from 0.70 to 2.59 m/s2 and, in four of seven trials, showed levels greater than 1.40 m/s2. The mean vector sum was 1.44 m/s2 with a STD of 0.75 m/s2. Comparatively, the newer trucks exhibited less variation with a range from 0.69 to 1.59 m/s2. The mean vector sum was 1.02 m/s2 with a STD of 0.35 m/s2. Vibration dose values for the dominant z-axis (VDVZ), gave a sense of vehicle jarring/jolting conditions. All trials with the older trucks were within the recommended EUGPG action level of 9.1 m/s1.75. On the other hand, in three of eight trials, both newer trucks exceeded this action level with values of 9.18, 12.58, and 13.21 m/s1.75. Neither truck group showed VDVZ that exceeded the exposure limit of 21 m/s1.75. A statistical analysis was not conducted, since the differences reported between truck groups may not be statistically significant owing to the relatively small sample size. Road conditions, changes in the truck routes, and driver/operator differences (e.g., stopping and turning) are possible factors in the higher VDV for the newer trucks.

Jan 1, 2008

By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared 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 countries. In the preparation of this interpretation of the laws of Norway, use has been made of William R. Orrmins' translations of various acts of the Norwegian Government, which were forwarded from the American consulate at Oslo^ and transmitted to the Bureau of Mines through the courtesy of the State Department. This digest is released subject to amplification and correction, if necessary, by the proper American foreignservice officers.

Nov 1, 1932

By F. E. Brantley

Blister copper was successfully deoxidized with any of a variety of reducing gases; lancing techniques or a vertical-column furnace were used to contact the copper and gases. Of the gases tested, butane, when used to lance molten copper at about 1,200° C, reaction temperature, was slightly more effective than propane, natural gas, carbon monoxide, or reformed gas for deoxidizing copper from about 1.0 to less than 0.1 percent oxygen content, Laboratory-scale tests revealed that the vertical furnace, composed of a heated column packed with silicon carbide chips or hollow carbon cylinders, was significantly faster and more efficient than the lancing technique for deoxidizing molten copper with any of the gases tested. Comparison of the gaseous-reduction method with the conventional poling method suggests that the gaseous method has important technical and economic advantages for deoxidizing blister copper to any readily controlled amount of residual oxygen content.

Jan 1, 1962

By Jacqueline A. McClaskey

The U.S. Bureau of Mines (USBM) Information and Analysis Directorate collects worldwide data on virtually every commercially important nonfuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U. S. economy. The USBM's data collection activity was instituted by the 47th Congress in an appropriations act of August 7, 1882 (22 Stat. 329), which placed the collection of mineral statistics on an annual basis. The most recent authority for the USBM survey activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress). This act strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1994

By J. H. Perry

The Bureau of Mines is conducting research to determine the effectiveness of long holes in degasifying an area of the Upper Split of the Lower Sunnyside coalbed at Kaiser Steel Co.'s Sunnyside No.1 mine. These holes were drilled from the two outside entries of a section that was closed to mining because of excessive methane emissions. Two holes drilled to 430 and 450 feet produced initial gas flows of 160,000 and 127,000 cfd, respectively. Sixteen days after the completion of the second hole, the total gas production declined to just over 144,000 cfd. In 9 months of degasification, over 35 MMcf of commercial-quality gas has been removed from the coalbed. The combined gas flows declined to 106,000 cfd in the 9-month period. The two holes have reduced face emissions by about 40 pet.

Jan 1, 1978

By R. K. Koch

The Bureau of Mines produced several series of titanium castings in order to investigate the feasibility of producing commercial-grade titanium castings in bentonite-bonded olivine or zircon sand molds. The use of these molds for titanium casting was investigated as a possible alternative to the industrially used rammed graphite process. Parameters investigated were mold mixtures, mulling, gating, venting, drying, and mold washing. The investigators found that castings with superior ductility and fatigue life, compared with rammed graphite castings, could be made by fume-free pro-cesses in molds bonded by western bentonite, using either olivine or zircon sand. Zircon molds were satisfactory for both light-and heavy-sectioned castings. However, olivine molds were suitable only for light-sectioned castings because the mold-metal reaction became excessive during the pouring of heavy-sectioned castings.

Jan 1, 1981

By Emery Chilton, Charles Taylor, Mark Senk, Linda McWilliams

Three-axis ultrasonic anemometers are used to study airflow in the NIOSH ventilation gallery where ventilation in an underground mine is simulated. In this study, performance characteristics of this anemometer are evaluated and the effects of sensor orientation and sampler location on flow readings are examined. The study results provide guidelines for more effective use of the ultrasonic anemometers in the ventilation gallery.

By A. Landsberg

Chlorination of sulfide minerals and several prepared metal sulfides was studied. The resulting data were analyzed with respect to kinetics of the reactions and application to nonpolluting methods of winning metals from sulfide ores. Sulfides of iron, copper-iron, nickel, lead, zinc, silver, bismuth, arsenic, rhenium, molybdenum, and tungsten were investigated at temperatures up to 600° C. Copper-iron, lead, and zinc sulfides showed at least some product-controlled (parabolic) kinetics at the lower temperatures within the temperature ranges studied, but only nickel and silver sulfides had chlorination rates controlled by parabolic reaction kinetics in the commercially important temperature range of 450° to 600° C.

Jan 1, 1975

By John A. Davis, John Gross

Six tests were made by the Alaska Station of the Bureau of Mines on a sample of black sand delivered to the station by Messrs. James, Eagan & Griffen from Fairbanks Creek, Fairbanks mining district, Territory of Alaska, to devise a method of recovering the gold content. More than 90 per cent of this black sand consisted of magnetite and garnet which can be separated magnetically. The Station has no equipment for magnetic separation other than an electromagnet similar to the one used by Day and Richards, (Day, D.T., and Richards, R.H., Investigations of Black Sands from Placer Mines, U. S. Geol. Survey, Bull. 285, 1906, pp. 150-163), which can only be used satisfactorily on small samples. To treat the entire lot of black sand with this machine would have been impracticable. Therefore only a small part of the sand was so treated, the rest being divided into five lots in order to obtain comparative results from other methods of treatment.

Aug 1, 1920

By S. J. Broderick

[One phase of the general program for utilization of coal-mine waste led to the possibility of making a water softener from the material, as the waste matter contained both coal and clay and it is known that both these substances can be so activated as to exhibit distinct base-exchange properties. The carbonaceous]

Jan 1, 1941

By C. A. Frenzel

Extensive spectroscopic data are needed in making reliable vibrational assignments for use in calculating thermodynamic functions of polyatomic molecules. The fundamental vibrations of organic molecules may be observed at any wavelength from 2.5 to 200 microns (micron = µ = 10-4 centimeters), but most often in the region from 3µ to 50µ. Raman spectra generally cover the range in which fundamental vibrations occur, but equally important infrared spectra usually are not measured at wavelengths longer than 25µ. This limitation results because most infrared spectra are determined for analytical purposes, which seldom require information outside the region 2µ to 25µ. Measurements of infrared spectra in the range 15µ to 35µ recently were begun by the Bureau of Mines to obtain data needed in making vibrational assignments. This report presents the spectra of the following thirteen compounds: Tetrahydrofuran, 1-methylpyrrole, piperidine, 2-methylpyridine, 3-miuthylpyridine, 2-propanethiol, cyclopentanethiol, 2-methyl-2-butanethiol, 3,3-dimethyl-2-thiabutane, cyclohexanethiol, cyclopentyl-l-thiaethane, 2,4-dimethyl-3-thiapentane, and hexamethyldisiloxane.

Jan 1, 1960

By S. J. Broderick

[The authors gratefully acknowledge the assistance of O. C. Ralston, chief engineer, Nonmetals Division, Bureau of Mines, Who suggested the problem and Gave valuable aid during the course of the work. Thanks axe due also to Will H. Coghill, supervising engineer of the Southern Experiment Station, Bureau of Mines. INTRODUCTION One phase of the general program for utilization of coal-mine waste led to the possibility of making a water softener from the material, as the waste matter contained both coal and clay and. it is known that both these substances can be so activated as to exhibit distinct base-exchange properties. The carbonaceous]

Jan 1, 1941

By McHenry Mosier

This paper describes come mechanical raid electrical signal systems in common use in Metal-mine shafts, together with several distinctive systems that indicate or control the origin of the signal. The latter systems remove the hazard of the movement of the cage from one level in response to signals from another. Previous publications of the Bureau of Mines have covered several meritorious installations One of the best signal systems for deep shafts is at the Homestake mine4/. A successful installation of an induction system in the Lake Superior mining region permits signaling as well as telephoning from cages at rest or in motion5/. El Potosi mine uses a variation of the three-wire electric system6/. A mine in Utah has developed a system of the double trolly-wire type, in which the cage attendant may signal from a moving cage7/. At present no system of the sine-shaft signaling employing radio is available.

Jan 1, 1939

By J. C. Holtz

Since 1937 the Bureau of Mines has conducted investigations to provide the technical information necessary to guide the safe use of diesel engines underground in the United States. Coincident with the beginning of the technical study, a survey was made of State regulations pertaining to the use of internal-combustion engines underground.3/ At that time it was found that owing to the known hazards of gasoline locomotives, many States had enacted legislation or regulations limiting or prohibiting their use underground. Some of this legislation prohibited, or could be interpreted as prohibiting, the use of any type of internal-combustion engines in underground workings. After World War II diesel-powered equipment was introduced underground in many States, and pertinent questions are received frequently by the Bureau of Mines about the regulations that permit such applications. Because it was known that new and revised regulations had been made effective in some States in the nearly 20 years that have elapsed since the previous survey,3/ the Bureau decided that a review of the latest regulations in the leading mineral-producing States would be a valuable source of information for those engaged in the production of minerals as well as others. Accordingly, where feasible, this report includes abstracts of State laws and regulations as they affect the use of internal-combustion engines underground, particularly diesel engines. The substance of comments from State officials also are included when these appear to be helpful to interpretation of the regulations.

Jan 1, 1957

By Seymour Wasserman

To develop noise control designs for secondary crushers in Taconite plants. Taken into consideration: 1. Acoustical criteria 2. Day-to-day operational considerations and maintenance accessibility 3. Materials of construction 4. Adaptability of design to other Taconite plants having crushers 5. Cost of noise control treatment.

Jan 1, 1977

By Roy Bartholomae

Noise generated by continuous mining machines in underground coal production is an important health hazard. Bureau of Mines Contract J0387229 covers investigation of this noise through laboratory tests of simulated cutting operations and through in-mine noise measurements. The results of these investigations indicate that coal cutting noise and conveyor noise are dominant sources of mining machine operational noise. Typical noise levels for both cutting and conveying operations are approximately 97 dBA (decibels A-weighted). For full operation of all machine systems, the overall sound pressure level is approximately 101 dBA. In-mine and laboratory test results show excellent agreement in both A-weighted overall levels as well as in A-weighted one-third-octave band spectra.

Jan 1, 1983

By P. H. Floyd

Laboratory test work has shown that the Germania ferberite-scheelite ore can be concentrated to an acceptable grade. A ferberite concentrate assaying 66.9 percent tungstic oxide was made, with a recovery of 75.4 percent. A second concentrate of ferberite and scheelite was made assaying 54.2 percent tungstic oxide. Final beneficiation of combined rougher gravity concentrates was accomplished by roasting, magnetic separation, sulfide flotation, and retabling, to give a final ferberite-scheelite concentrate of 66.2 percent tungstic oxide, with a 91.1-percent recovery. INTRODUCTION This presentation covers the results of laboratory beneficiation tests conducted on tungsten ore from the Germania Consolidated Mines, Inc., by the Bureau of Mines Mineral Dressing Section, Northwest Electrodevelopment Laboratory, Albany, Oreg. This mining property is near Fruitland, on the southern edge of the Spokane Indian Reservation, Stevens County, Wash. The Germania district produced tungsten concentrates before and after World War I; interest is being renewed in the district because of the metal shortage.

Jan 1, 1954

By G. Richards Gwinn

Vermiculites are secondary minerals formed by the: alteration of biotite and philogopite mica and are associated with basic rocks such as dunites, serpentines, and pyroxenites. Vermiculite was first described by T. H. Webb in 1824. It remained a mineralogical curiosity until 1913, when the first commercial deposit was discovered in the Turrett mining district of Colorado. Expanded or exfoliated vermiculite was first marketed in 1915 from a deposit in this district 5 miles southeast of Hecla, Colo. This activity was brief, but successful and continuous commercial development began in 1921 in Montana. 'Deposits in other States have been found and developed, but Montana is by far the largest producer. Vermiculite has also been found in South Africa, Western

Jan 1, 1944

By A. B. Needham

This paper, which describes mining practices at a mine in the Cave- in-Rock, Illinois, fluorspar district, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. Ore deposits in the southern Illinois-western Kentucky fluorspar dis- trict are of two general types (1) the flat-bedded, lenticular replacement and (2) the relatively narrow, rather steeply dipping fault or fissure filling. This paper describes production methods used and results obtained in mining one of the bedded lenticular ore bodies that are prevalent in the northeast portion of the district near Cave-in-Rock.

Aug 1, 1949