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By Gerald T. Homce

Data from the U.S. Bureau of Labor Statistics show that 89 water well drillers died on the job between 1992 and 2002, and 28 of these deaths were electrocutions (Figure 1). In fact, elec­trical accidents are the leading on-the-job killer of water well drillers. The use of electricity is such an integral part of our lives that we usually take it for granted, but if we don?t understand or choose to ignore the hazards associated with electricity, the results can be deadly. Why is electrical shock so dangerous? If the voltage (of a shock) is sufficient to drive electrical current through your body, just 10 milliamps of cur­rent (1000 milliamps = 1 amp) can cause muscles to contract and prevent you from releasing an energized wire or tool in your grip. As little as 30 milliamps of current can paralyze your breathing, and 75 milli­amps can cause your heart to stop pumping blood (ventricular fibrillation). As a comparison, a small bedroom night-light draws about 30 to 60 milliamps. Other factors influence how severely you?ll be shocked if you touch a live electrical circuit, such as the path electrical current takes through your body and how long it flows, as well as your body weight. How much voltage is needed to drive electrical cur­rent through your body? Not much! Generally, any power source at 50 volts AC or higher is considered dangerous.

Jan 1, 2008

By J. B. Czirr

MESA Corporation has completed a four-year program for the Bureau of Mines to develop a technique for measuring roof competence in underground coal mines. The preferred technique employs a tracer gas that is injected into a roof borehole drilled near the working face. The tracer gas performs the dual purpose of determining the pressure loss rate from the borehole and of marking the diffusion pattern of the the escaping gas. The primary detection technique relies upon observation of the rate of pressure drop in a hole drilled in the roof strata under test. If this measurement indicates a significant probability of roof collapse, the gas diffusion pattern is outlined with the Leak-gun tracer-gas detector. These two techniques provide a comprehensive method for predicting the relative probability of roof collapse in operating coal mines.

Jan 1, 1985

By G. K. Derby

Five different types of drilling systems were developed under the flexible drill program that was initiated by the Federal Bureau of Mines to protect roof bolter operators. The systems were designed for underground coal mines with seams as low as 30 inches, and with roof bolts longer than the height of the seam opening. Four of the developed systems were true flexible drills; the fifth was a remote-controlled, automatic rod changer concept. Only two of the five firms successfully completed testing requirements under the original contracts: BendixCorp.,4 with a true-flex drill; and Ingersoll-Rand Research, Inc., with the rod changer concept. The Bendix drill was rated best, and the Ingersoll-Rand drill was rated second. Because of the closeness of the ratings and the vast differences in the two development concepts, both systems had sufficient potential to justify further development funding for design updating and testing. Also, both systems warranted consideration for inclusion into other ongoing development projects under both safety and energy directed programs.

Jan 1, 1978

The principal activities of the Bureau of Mines Explosives Research Center during fiscal year 1969 (July 1: 1968, to June 30, 1969) are reviewed in part 1. Part 2 presents short abstracts of the publications issued during this period in the Bureau series and in the outside press. These publications are referenced in part 1 by underlined numbers in parentheses. Other publications, which are not abstracted, are cited in footnotes throughout the paper. ACKNOWLEDGEMENTS The Bureau acknowledges the support received through cooperative agreement in fiscal year 1969 from the Manufacturing Chemists Association. It also acknowledges the sponsorship by the following Government agencies of research conducted during that period: Department of the Air Force, Department of the Army, Department of Health, Education, and Welfare, Department of the Navy, Federal Aviation Administration, National Aeronautics and Space Administration, Space Nuclear Propulsion Office, and United States Coast Guard.

Jan 1, 1970

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most, States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the Oklahoma Planning and Resources Board of the Conservation Commission has been authorized to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By Richard Quirk

This report describes methods and techniques employed by The Glidden Co. of Cleveland, Ohio, in explorating an ilmenite-bearing sand deposit in Ocean County, New Jersey, during 1960 to determine ore reserve potential and the feasibility of mining and establishing a milling plant on the property for the production of ilmenite concentrate. The property covered approximately 1,250 acres. Comprehensive sampling by water-jet drilling indicated the deposit averaged 20 feet in thickness and contained 4.5 percent heavy minerals, of which 80 to 85 percent was ilmenite and leucoxene. Average depth of the water table as determined by auger boring was 16.8 feet. Pilot plant tests indicated that circular concentrators in combination with spiral concentrators would recover at least 80 percent of the heavy mineral content of the sands. It was estimated that sufficient ore reserve tonnage had been developed to supply the company's Baltimore chemicals division, pigments department, with a suitable grade ilmenite concentrate for a period of 20 years at the present rate of pigments production. The property was designated as Lakehurst mine and plans are in progress for mining development and plant construction.

Jan 1, 1963

By Everett P. Partridge, J. E. Conley

Available statistics show that the demands of the American chemical industry for sodium sulphate have been increasing slightly in recent years. The supply from domestic sources, particularly in the form of byproduct salt cake from the acid manufacturers, has been tending to decrease this to the growing manufacture of synthetic acid. Both hydrochloric and nitric acids are being synthesized from their elements. The natural result has been that a smaller amount of salt cake is available. Simultaneously, the expansion of the kraft-paper industry, especially in the South, has brought about greater demand for sodium sulphate in that section. This demand is being met by domestic byproduct salt cake, by imported German sodium sulphate made from potash waste liquors, and by favorably situated domestic deposits of Glauber salts and the anhydrous salt, thenardite. No shortage of natural sodium sulphate exists in the United States, but usually such deposits occur in semiarid regions far removed from transportation facilities and from markets. Moreover, the major portion of the natural deposits is Glauber salt or mirabilite (Na2 504 • 10H20), which must be dried or dehydrated in order to meet consumer requirements. The water of hydration represents, roughly, 55 percent of the total weight of the crude salts and therefore has a very important influence on transportation costs, in many instances the cost of getting even the dehydrated product to market is the deciding economic factor. Therefore, the recovery of production of anhydrous sodium sulphate from plant-waste liquors or from natural brines of suitable composition might be economically feasible.

Mar 1, 1936

By J. M. Gomes

Bench-scale flotation tests were conducted on two western tactite ores to study the recovery of tungsten and zinc minerals. The investigation, which is part of the Bureau of Mines ongoing program to develop methods for beneficiating minerals and metals from domestic low-grade ores, demonstrated the feasibility of producing scheelite, sphalerite, and their bulk concentrates. Sphalerite concentrates containing 51 to 53 pet Zn and less than 0.11 pct W03 were selectively recovered prior to scheelite flotation. Zinc recovery ranged from 85 to 91 pct. Scheelite concentrates containing 17 to 25 pct W03 were then recovered from the ore; tungsten recoveries ranged from 88 to 94 pct. Bulk flotation concentrates containing 84 to 91 pct of the W03 and 87 to 95 pct of the zinc also were prepared. More than 98 pct of the W03 in a bulk concentrate containing 9 pct W03 was extracted by autoclave leaching with a soda solution. The zinc remained in the leached residue.

Jan 1, 1982

By J. W. Eckerd

This report describes an investigation of the technical feasibility of using a conventional commercial-size (10-ft. i.d.), rotating grate, dry-ash-removal type gas producer to make producer gas from chestnut-size bone anthracite. Test instruments were installed, and some minor changes were made in the equipment to handle the large quantities of materials expected. Extensive tests, lasting about 4 weeks, were planned, using 35 to 50 percent ash chestnut anthracite bone. However, operations were suspended after 8 days when it became apparent that to use this type of fuel satisfactorily substantial changes in equipment and operating procedures would be required. Nevertheless, enough data were obtained to indicate that gas could be produced continuously and routinely from bone coal in this type of producer whenever conditions justified the necessary development work.

Jan 1, 1960

By William H. Pomroy

The Bureau of Mines, through a 4-year program of combined in-house and contract research, has developed the necessary hardware and software technology to provide rugged, reliable automatic fire protection for surface mining mobile equipment. One element of this program was a continuing effort to help foster rapid mining industry acceptance of the technology by keeping end user costs reasonable. This report is an analysis of the economic impact of surface mining mobile equipment fires and the cost benefit of utilizing automatic fire protection systems to abate these losses.

Jan 1, 1982

By Paul Meadows

This Bureau of Mines report presents operating practices and results of pressure maintenance and secondary recovery by water injection or by water injection supplemented by gas injection. Particular emphasis is placed on the results of water injection, which is the principal oil-recovery method employed in projects covered by this report. No attempt is made to study gas-injection projects or operations that are considered water-disposal projects. Also, this report does not include water-injection projects that have not been in operation long enough to evaluate results. Figure 1 is a map of north Louisiana showing the geographical locations of the projects included in this report. Most of the data used in this study were supplied by unit operators, operating companies, and the Louisiana Department of Conservation. Reservoir information and recovery data are generally those supplied by the operators, but include revisions where deemed necessary.

Jan 1, 1962

By Rethel L. Hubbard

Fourteen straight-run asphalts were prepared in the laboratory from bitumens obtained from three sources: (1) native bitumen from Rozel Point, Utah, (2). bitumen extracted from Athabaska bituminous sandstone at Canada, and (3) bitumen extracted from Edna bituminous sandstone outcropping in San Luis Obispo County, to seven asphalts with penetrations ranging from 19 to 287 at 77 F. were prepared from each of the bitumens. The yields of the prepared asphalts ranged from 74.5 percent for a 27-penetration asphalt from the Athabaska bitumen to 99.5 percent for a 271-penetration asphalt from the Rozel Point bitumen.

Jan 1, 1949

By W. H. Schiffbauer

NIOSH has developed an active proximity warning system called HASARD (Hazardous Area Signaling and Ranging Device) for warning workers as they approach known dangerous areas around heavy mining equipment and other dangerous work zones. HASARD is composed of a transmitter and a receiver. The transmitter generates a 60-kHz magnetic field using one or more wire loop antennas. Each antenna is adjusted to establish a magnetic field pattern for each hazardous area. The receiver, worn by the worker, is a magnetic field strength meter. The received signal is compared against preset levels which are calibrated to identify levels of danger. The receiver outputs can include visual, audible, and vibratory indicators and it can also be made to disable machine functions. HASARD was field tested on a Joy 12 continuous miner, a Komatsu 210 M Haulpak, and on a highwall launch vehicle. Slight modifications were made for each application. HASARD provided warnings as designed and proved to be rugged enough to withstand the harshest of production environments.

By T. F. Mitchell, J. V. Batty, R. R. Wells, R. Havens

"INTRODUCTION )ne of the most important wartime activities of the Bureau of Mines was the search for new sources of minerals necessary to the prosecution of the war. As a part of the investigation of strategic mineral deposits in the United States under the Strategic Minerals Act (Public 117, 76th Cong., 1st Sess., Ch. 190), examining engineers of the Bureau of Mines investigated and sampled various deposits of chrome ore in California, Idaho, Montana, Oregon, and Washington, and those deposits that warranted further study were explored by diamond drilling, trenching, and drifting, as re¬quired. During these investigations, samples were submitted to the Ore Dressing Section of the Salt Lake City Station for metallurgical testing. This paper gives data summarizing results obtained from laboratory ore-dressing studies of the chrome ores submitted.Although the deposits range widely in geographical location, the mineral occurrence of all of them is strikingly similar. Chromium, in all of the ores tested, is present as impure chromite or chromium spinel. Although pure chromite (FeCr204 or FeO.Cr203) contains 68 percent chromic oxide, the iron may be replaced in varying amounts of magnesium, and the chromium may be replaced similarly by aluminum and ferric iron. In studying concentration methods as applied to chrome ores, the composition of the chrome mineral is of fundamental importance, because it is manifestly impossible to produce a high-chrome concentrate from a low-chrome chromite by any mechanical process.In all but one of the ores, the gangue material consists of olivine or altered olivine minerals such as serpentine, antigorite, and chrysotile. The exception, the Antelope or from Montana, has a gangue chiefly composed of actinolite, chlorite, and talc."

Jun 1, 1947

By R. Blickensderfer

The sparking and gas-igniting tendency of steels and alloys were evaluated my measuring the radiance of spark showers produced by grinding a sample on an abrasive wheel in air, the time required for a spark shower generated on an abrasive wheel to produce an ignition in an explosive gas mixture, and the energy and speed required for impacts between various materials to ignite an explosive gas mixture. Mixtures of air-methane were found quite resistant to ignition by showers of sparks. A mixture of air-9.S pct hydrogen was used to increase the sensitivity of the tests and to thereby extend the range of materials that could be evaluated. The results of the spark-shower tests indicate that carbon steels and the alloy steels found in coal-cutter tools are among the most sparking and most incendive of any materials tested. Stainless steels, nickel alloys, and tungsten carbide are among the least sparking and least incendive. The brightness of the spark showers depended upon the degree of oxidation of the abraded particles. Impact tests against hard rocks such as solid quartz and sandstone, showed that high-carbon steel was more inc endive in the hydrogen mixture than were the softer steels or the alloy steels found in coal cutters. Ignitions were found much less likely to occur at speeds somewhat lower than the speeds currently in use in continuous mining machines.

Jan 1, 1972

By E. P. Youngman

The Siamese mining lew, which is cited as "The Sian Mining Act, 2461 (1919)," was enacted February 14, B. E. 2461 (A. D. 1919), corresponding to the ninth year of His Majesty's reign. This act replaces the Sian Mining Act of 1901 and repeals all edicts, decrees, laws, rules, and local customs relating to mining the terms of which are inconsistent with the new law. It shall in- clude all subsequent alterations or additions, as well as all rules issued by the Minister (of Land and Agriculture) already in force or to be brought into force publication in the Government Gazette to be deemed sufficient notice of any modifications or alterations. (Art. 1, 2, 5, 83, and 85.) Legislation passed recently amending certain provisions of the mining law for the purpose of controlling the sale of minerals is the mining amendment act, B. E. 2474, given August 21, 1931 (7th year of the present reign), which repeals provisions of the mining act, B. 3. 2461, and also all rules and regula- tions relating to mining that are inconsistent with the amending ect. Under article 25 of the mining amendment act, B. E. 2474, ministeriel regulations (of the Minister of Agriculture) were issued August 21, 1931. Further recent legislation, brought about by the agreement of the Siamese Government to become a party to the international tin restriction scheme (inter- national tin pool), is the tin and tin ore restriction act (Siam), B. E. 2474, which came into force on September 1, 1921, its purpose being to suspend the

Mar 1, 1933

By Clayton M. Rumsey

In 1984, the U.S. Bureau of Mines conducted a mineral survey of a 26,598-acre study area which includes the 23,702-acre Mt. Limbo Wilderness Study Area (NV-020-201). The study area is 65 miles northeast of Reno, NV, and is underlain mainly by Cretaceous granodiorite that comprises the Selenite Range. Tertiary basalt, rhyolite, and sedimentary rock as well as Quaternary alluvium and lake deposits are exposed near the study area boundary. Mines just north of the area in the Hooker mining district produced tungsten ore in the 1940's and 1950?s. Similar deposits are not known in the study area. Disseminated gold is in sinter about 6 miles west of the study area and at several other locations regionally.

Jan 1, 1986

By John C. Machisak

INJURY EXPERIENCE AND EMPLOYMENT DATA on all stone quarries and associated plants in the United States are presented in this publication for the calendar year 1959. Such related operations as the manufacture of cement and lime and rock dressing are included. Data on clay and sand and gravel operations are not included and will be found in other Bureau publications on injuries and employment. The Bureau is authorized to make requests for such data and the information voluntarily submitted by the operators contributes to the promotion of safety in the quarrying industry. Every effort has been made to make this canvass as complete as possible. Data for production workers and office employees at the quarry site are included.

Jan 1, 1963