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By Thomas W. Martin

This chapter includes tables from 1984 that were not available in time for publication of the 1984 Minerals Yearbook, but does not include corresponding tables for 1985. The value of raw nonfuel minerals produced in the United States during 1985 was estimated at $23.2 billion, an increase of $0.07 billion over the value for 1984. This is the third consecutive year that the value has increased, and except for a decrease in 1982, the value for each year has increased since 1971, or 13 out of 14 years. However. while the value of industrial minerals production continued to grow, reflecting the growth of the domestic economy, the value of metal mine production decreased in 1985 by 6%. This drop was more than offset by a 3% increase in the value of industrial minerals production because the value of industrial minerals produced was more than three times larger than the value of metals. The decrease makes 1986 the third year in the past 5 years in which a drop in the value of metal mining production occurred in the United States where production continued to lag behind growing world production. Domestic production of such major commodities 88 aluminum, copper, iron ore, phosphate rock, and zinc continued to decline owing to a number of international and domestic factors. Gold continued to be the most active commodity in the domestic metal mining industry. Despite lower prices, gold output increased to 2.5 million troy ounces, a 19% increase over that of 1984. The estimated annual production capacity of new gold mines beginning production exceeded 1 million ounces.

Jan 1, 1987

By Thomas J. Fisher, John J. Sammarco, Gary L. Mowrey, Edward F. Fries

This report (Safety File 3.0) is the fourth in a nine-part series of recommendations addressing the functional safety of processor-controlled mining equipment. It is part of a risk-based system safety process encompassing hardware, software, humans, and the operating environment for the equipment’s life cycle. Figure 1 shows a safety framework containing these recommendations. The reports in this series address the various life cycle stages of inception, design, approval and certification, commissioning, operation, maintenance, and decommissioning. These recommendations were developed as a joint project between the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration. They are intended for use by mining companies, original equipment manufacturers, and aftermarket suppliers to these mining companies. Users of these reports are expected to consider the set in total during the design cycle. • 1.0 Safety Introduction.—This is an introductory report for the general mining industry. It provides basic system/software safety concepts, discusses the need for mining to address the functional safety of programmable electronics (PE), and includes the benefits of implementing a system/software safety program. • 2.1 System Safety and 2.2 Software Safety.—These reports draw heavily from International Electrotechnical Commission (IEC) standard IEC 61508 [IEC 1998a,b,c,d,e,f,g] and other standards. The scope is “surface and underground safety-related mining systems employing embedded, networked, and nonnetworked programmable electronics.” System safety seeks to design safety into all phases of the entire system. Software is a subsystem; thus, software safety is a part of the system’s safety. • 3.0 Safety File.—This report contains the documentation that demonstrates the level of safety built into the system and identifies limitations for the system’s use and operation. In essence, it is a “proof of safety” that the system and its operation meet the appropriate level of safety for the intended application. It starts from the beginning of the design, is maintained during the full lifecycle of the system, and provides administrative support for the safety program of the full system. • 4.0 Safety Assessment.—The independent assessment of the safety file is addressed. It establishes consistent methods to determine the completeness and suitability of safety evidence and justifications. This assessment could be conducted by an independent third party. • 5.0 Safety Framework Guidance.—It is intended to supplement the safety framework reports with guidance providing users with additional information. The purpose is to assist users in applying the concepts presented. In other words, the safety framework is what needs to be done and the guidance is the how it can be done. The guidance information reinforces the concepts, describes various methodologies that can be used, and gives examples and references. It also gives information on the benefits and drawbacks of various methodologies. The guidance reports are not intended to promote a single methodology or to be an exhaustive treatment of the subject material. They provide information and references so that the user can more intelligently choose and implement the appropriate methodologies given the user’s application and capabilities. [ ]

Jan 5, 2002

By James A. Powell

The theory of electromagnetic fields indicates such fields could be used to detect and locate trapped miners. To be useful, the hardware of the system must meet a number of requirements, including small size, intrinsic safety, and rugged construction. Such hardware has been built, and the system has been tested by the Bureau of Mines and its contractors. These tests indicate that the electromagnetic method provides a practical means to locate miners in emergencies.

Jan 1, 1976

By J. Roger Loebenstein

Small amounts of arsenic trioxide were shipped in 1988 from remaining stocks at ASARCO Incorporated's closed plant at Tacoma, WA. Imports of arsenic trioxide were at about the same level in 1988 as in the previous year. Legislation and Government Programs The Occupational Safety and Health Administration (OSHA) levied a $1.6 million fine against Asarco for exposing its workers at its East Helena lead smelter in Helena, MT, to unacceptably high levels of lead and arsenic. The bulk of the fine was for violations of a respiratory protection program. The same smelter and its environs has been listed as a Superfund toxic-waste site by the Environmental Protection Agency (EPA). Tests had shown high levels of lead, cadmium, and arsenic in the soil near the smelter. EPA planned to extend the cleanup to areas within the town of East Helena because high levels of arsenic had been found in shallow test wells outside the smelter site. Federal and State health officials have warned residents living in the vicinity of East Helena to avoid eating certain home-grown vegetables because of high concentrations of heavy metals.2

Jan 1, 1990

By John J. Sammarco, Edward F. Fries

This report (Independent Functional Safety Assessment 4.0) is the fifth in a nine-part series of recommendations addressing the functional safety of processor-controlled mining equipment. It is part of a risk-based system safety process encompassing hardware, software, humans, and the operating environment for the equipment’s life cycle. Figure 1 shows a safety framework containing these recommendations. The reports in this series address the various life cycle stages of inception, design, approval and certification, commissioning, operation, maintenance, and decommissioning. These recommendations were developed as a joint project between the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration. They are intended for use by mining companies, original equipment manufacturers, and aftermarket suppliers to these mining companies. Users of these reports are expected to consider the set in total during the design cycle. • 1.0 Safety Introduction.—This is an introductory report for the general mining industry. It provides basic system/software safety concepts, discusses the need for mining to address the functional safety of programmable electronics (PE), and includes the benefits of implementing system/software safety program. • 2.1 System Safety and 2.2 Software Safety.—These reports draw heavily from International Electrotechnical Commission (IEC) standard IEC 61508 [IEC 1998a,b,c,d,e,f,g] and other standards. The scope is “surface and underground safety-related mining systems employing embedded, networked, and nonnetworked programmable electronics.” System safety seeks to design safety into all phases of the entire system. Software is a subsystem; thus, software safety is a part of the system’s safety. • 3.0 Safety File.—This report contains the documentation that demonstrates the level of safety built into the system and identifies limitations for the system’s use and operation. In essence, it is a “proof of safety” that the system and its operation meets the appropriate level of safety for the intended application. It starts from the beginning of the design, is maintained during the full lifecycle of the system, and provides administrative support for the safety program of the full system. • 4.0 Safety Assessment.—The independent assessment of the safety file is addressed. It establishes consistent methods to determine the completeness and suitability of safety evidence and justifications. This assessment could be conducted by an independent third party. • 5.0 Safety Framework Guidance.—It is intended to supplement the safety framework reports with guidance providing users with additional information. The purpose is to assist users in applying the concepts presented. In other words, the safety framework is what needs to be done and the guidance is the how it can be done. The guidance information reinforces the concepts, describes various methodologies that can be used, and gives examples and references. It also gives information on the benefits and drawbacks of various methodologies. The guidance reports are not intended to promote a single methodology or to be an exhaustive treatment of the subject material. They provide information and references so that the user can more intelligently choose and implement the appropriate methodologies given the user’s application and capabilities. [ ]

Jan 5, 2003

By Thomas V. Falkie, R. Venkataramani

Table

Jan 1, 1972

By Robert W. Freedman

Vacutainers are used by the Bureau of Mines and the Mining Enforcement and Safety Administration (MESA) for sampling mine air and products of combustion. Tests were conducted on both 10-ml and 30-ml sizes to study shelf life stability during storage, pretreatment of stoppers, and handling of a wider range of compounds. A chamber was constructed to provide convenient, efficient evacuation of the Vacutainers shortly prior to use. Fixed gases and C1 ?C5 hydrocarbons could be stored for 1 week or more after sampling. Where decreases occurred (C02 and C3-C5 hydrocarbons), they were predictable as a function of storage time. An unexplained phenomenon, slow accumulation of CO in evacuated Vacutainers, occurred after a few weeks of storage. The levels were low and time dependent. Attempts to eliminate this behavior by pretreating the stoppers were unsuccessful.

Jan 1, 1976

By Clinton C. Knox

During the latter part of 1943, a magnetometric survey was conducted by the Geophysical Division of the Bureau of Mines at the Mahopac magnetite mine, Putnam County, N. Y., in an endeavor to locate a segment of the ore body that reports state was cut off by a fault. The Mahopac mine was abandoned about 1895 after producing nearly 1,000,000 tons of high-grade magnetite iron ore. The results of the investigation indicate the termination of the ore body by "pinching", or a displacement of such magnitude as to place any extension at a considerable distance from the original are body. This report describes the work done on the project and presents the data obtained.

Jan 1, 1948

By James L. Konchesky

Crushed coal, consisting of a wide range of sizes, was effectively blended by recycling it through a bin equipped with a particle distributor. Vertical blending was accomplished by simply recycling the coal; it was not significantly influenced by the horizontal blending that was achieved by the distributor. The method was effective, even though the coal was wet and possessed poor flowing characteristics. Recirculation appears capable of providing uniform blends of solids that can be more efficiently processed. Recirculation also appears useful, preceding packaging operations, to insure for blending of solids into specification products. Continuous measurement of the bulk density of the coal by a gamma ray meter proved to be an effective monitor of vertical blending effectiveness.

Jan 1, 1972

By Thomas E. Green

A solvent extraction procedure using 8-hydroxyquinoline and chloroform was investigated by the Bureau of Mines as a preconcentration technique for the determination of aluminum, calcium, cobalt, copper, iron, lead, magnesium, manganese, nickel, and zinc in large samples of high purity tungsten. X-ray spectrographic and atomic absorption methods were used to determine the trace metals after preconcentration. The presence of 10 grams of tungsten had a pronounced effect on the distribution of 8-hydroxyquinoline between the aqueous and chloroform phases. This change in the 8-hydroxyquinoline distribution in turn had an adverse effect on the extraction of the trace metals. Extraction efficiencies can also be adversely affected by an increase in the quantity of extractable metals present, as shown by radiotracer tests using 65Zn. Excess 8-hydroxyquinoline in the extracts did not interfere with the determination -of the serious interference in the combined ion exchange paper--X-ray spectrographic method. Although preconcentration by 8-hydroxyquinoline extraction was found to be partially successful, other preconcentrationn methods based on ion exchange and dithizone extraction were found to be superior.

Jan 1, 1968

By Philip E. Sanker

The Bureau of Mines conducted small-scale batch and semicontinuous tests on the reduction of zinc sulfide with iron according to the reaction ZnS + Fe ? FeS + Zn to determine reaction kinetics in the temperature range 1,000° to 1,400° C and to investigate the potential use of a scrap iron reductant. Batch tests indicated that a temperature of at least 1,300° C with a 1:1 mole ratio of Fe to ZnS is needed for good zinc recovery. Semicontinuous tests were conducted, using four zinc concentrate samples, containing various percentages of copper, cadmium, and lead, which were reacted with iron and iron contaminated with iron oxide and tin in an externally heated graphite furnace. Analysis of the zinc metal and FeS matte reaction products showed cadmium to be entirely in the zinc metal, copper to be in the FeS matte, and lead to be about 60 pct in the zinc metal and 40 pct in the matte. Tin reported to the matte, and none was detected above the O.OS-pct level in the zinc. Sulfur dioxide was not detected in the offgas when up to 20 pct of the iron was replaced by Fe203.

Jan 1, 1976

By L. E. Geyer

"The following list gives the title and author of various publications of the Ceramic Experiment Station, Columbus. Ohio, of the Bureau of mines, together with other ceramic publications of the bureau, which have been published in technical journals and by cooperating agencies. The list also includes the publications on ceramics which have been issued as bulletins, technical papers, or mimeograph Report of Investigations of the bureau.Papers Published in the Technical Press.The Effect of some Electrolytes on the Properties of Clays. Schurecht, H.G. Jour. Am. Cer. Soc., Vol. 1, #3, March, 1918.A Pycnometer Operated as a Volumeter. Schurecht, H.G. Jour. Am. Cer. Soc.,Vol. 1, #8, August, 1918.The Properties of some Ohio and Pennsylvania Stoneware Clays. Schurecht,H.G. Jour. Am. Cer. Soc., Vol. 1, #4, April, 1918.The Fusibility of Graphite Ash and its Influence on the Refractoriness of Bond Clay. Booze, M.C. Jour. Am. Cer. Soc., Vol. 2, #1. Jan., 1919.Behavior under Brass Foundry practice of Crucibles containing Ceylon, Canadian and Alabama Graphites. Stull, R.T. Jour. Am. Cer. Soc., Vol. 2, #3. March, 1919."

Oct 1, 1924

By W. R. McDonald

The Bureau of Mines, U.S. Department of the Interior, conducted small-scale field tests on acidic copper tailings as part of its effort to develop, improve, and demonstrate technology for stabilizing mining and mineral-processing wastes. Two successful demonstration revegetation plots were established on an abandoned copper-tailings pond located on public land adjacent to Holden Village, Wash. The tailings were neutralized with treatments of either dolomitic lime or limerock and fertilized with processed sewage sludge and/or commercial fertilizer. Excellent plant growths covering 70 and 24 percent of the surface were achieved on 1/8-and 1-1/2-acre test plots planted in 1973 and 1974, respectively. Regar brame, Tegmar intermediate wheatgrass, and tall wheatgrass provided the best plant growth and surface coverage. The target pH of tailings neutralization was 6.8; however, good plant growth occurred in areas where the soil pH ranged from 2.9 to 5.8.

Jan 1, 1978

By A. J. Kraemer

[A great deal of interest has been manifested in the question of sulphur in fuels for automobile engines. Many different opinions have been expressed with respect to the effect of sulphur in gasoline on engine wear and engine performance. A wide difference of opinion exists as to the permissible limit of sulphur content for satisfactory operation.]

Jan 1, 1927

By H. O. Poppleton, F. E. Block

This investigation was made to develop a method of preparing high - purity thorium metal in quantities up to 20 kilograms per batch . Several methods for the preparation , purification , and reduction of thorium tetrachloride are discussed . Thorium tetrachloride was prepared by chlorination of decomposed thorium nitrate or oxalate with carbon tetrachloride or phosgene . tion of the crude tetrachloride was achieved by multiple distillations or by filtration of the molten chloride . It was found that high - purity thorium metal could be prepared by sodium reduction of thorium tetrachloride if chloride of sufficient purity were available . Byproduct salts and excess reductant were removed by vacuum distillation , and the resultant thorium metal sponge was consolidated by consumable - electrode or fixed - electrode arc melting . It was demonstrated that metal prepared by this method could be fabricated into bar , rod , or sheet , at room temperature .

Jan 1, 1964

By H. J. Heinen

Malononitrile [CH2(CN)2J, which forms a carbanion in basic solutions, was investigated as a potential leachant for gold and was shown to be an effective extractant in alkaline pulps. Malononitrile was comparable to equal molar quantities of sodium cyanide (NaCN) in leaching gold from an oxide ore and yielded 10 to 20 percent higher recovery in leaching a refractory carbonaceous ore, although dissolution was slower with malononitrile than with cyanide. Complete recovery of the gold from the pregnant solutions was achieved by coprecipitation with a lead salt on zinc dust; the leachant was shown to be capable of regeneration and recycling a limited number of times. Addition of an anion-exchange resin to the carbonaceous pulp containing malononitri1e increased gold recovery from 67 to 95 percent. Some malononitrile derivatives were also shown to be gold solvents.

Jan 1, 1970

By D. E. Hirsch

The Bureau of Mines has developed a systematic procedure for separation, characterization, and semiquantitative analysis of high-boiling (350° to 550° C) distillates of crude oils. Isothermal and molecular distillation were used to prepare the 370° to 530° C distillate of Recluse, Wyo., crude oil. The distillate was separated into fractions by chemical treatment, silica-alumina gel adsorption, and gel permeation chromatography (GPC). The fractions were analyzed by use of GPC correlations and mass and nuclear magnetic resonance (NMR) spectrometry. The increased knowledge of petroleum composition obtained from the data will contribute to improved petroleum processing and utilization and energy conservation.

Jan 1, 1974

By C. J. Tsai, K. Olson, R. Caldow, B. Cantrell, D. Y. H. Pui

"The amount of new surface generated during fracture of coal and rock has been found to be directly proportional to the amount of energy associated with the fracture. To confirm this and study the relationship between the new surface and dust aerosol formed during fracture the U.S. Bureau of Mines has conducted experiments simulating fracture as it occurs during mining operations. In addition to fracture energy measurements, fragment size distributions were determined over a size range of 0.5 microns to 1 inch. The size measurements accounted for the mass of the original sample. Material studied was Illinois No. 6 coal, coal from the Taggart seam of Virginia, and Berea Sandstone. The experiment employed a chamber to confine sample fracture fragments and a combination of particle measuring systems. Measurement methods included aerodynamic sizing of entrained dust aerosol with optical counting and inertial impaction techniques, physical sizing of non-airborne fragments by sieving, and optical sizing of fragments using optical counting and scanning electron microscopy.Results of the size distribution measurements indicate that a single size distribution law does not adequately describe the entire fragment size distribution. A combination of two size distribution laws, such as the Rosin-Rammler and log-normal distributions, is necessary to describe this size distribution. New surface created by fracture is primarily found 1n particulate between 2 and 50 microns with a mean size of 12 microns. It was also found that the specific energy of fracture can be linearly related to the .concentration of aerosol in this size range.Only a .small fraction, between 0.02 and 0.16 pct, of the dust particles .generated during fracture become airborne. The remainder adhere to the new surface created during fracture. An entrainment fraction, defined for a given particle size is the ratio of the mass of airborne particles to that of the total particles generated in that size range. This experimental entrainment fraction is related to the Van der Waals adhesion force and the electrostatic forces operating during fracture and is used to derive empirical parameters to model these two processes."

Jan 1, 1989

By H. C. Ko

The Bureau of Mines maintains an active program in thermochemistry to provide thermodynamic data for the advancement of mineral science and technology. As part of this effort, the standard enthalpy of formation at 298.15 K, ?Hf°, for 2CdO-CdSO4 was determined by HCI acid solution calorimetry to be -345.69 ±0.61 kcal/mol.

Jan 1, 1983

By R. H. Storch

This report describes work done as part of a Bureau of Mines program to appraise the titanium-mineral resources of Idaho. The work included both field reconnaissance and a spot churn-drilling program. Much general information was available, as a result of earlier work done under the Western Radioactive Minerals Exploration Program conducted between 1950 and 1954 by the Bureau of Mines for the United States Atomic Energy Commission. This particular exploration provided data as to the quantity of ilmenite (TiFe03) and accessory black-sand mineral concentrates in a number of placer deposits; however, at that time no tests were made to ascertain if the ilmenite was of marketable grade. The spot churn drilling was begun in the Gold Fork area of Long Valley, Valley County, Idaho (fig. 1), in August 1956 and was completed during October of the same year. Eleven holes (designated as the GF series on fig. 2) 35 to 45 feet in depth, aggregating 425 feet, were completed during this period. Data from other exploration drilling in 1951 was used in this report. The 13 holes in the G series shown in figure 2 were drilled by the Bureau of Mines for the United States Atomic Energy Commission; the 7 holes of the DH series were drilled by the Bureau of Reclamation. The 20 holes, ranging from 16 to 140 feet in depth, totaled 1,625 feet. The combined number of all samples recovered was 422. Those taken in 1956 were composited for each drill hole and sent to the Bureau of Mines laboratory in Albany, Oreg., for analyses.

Jan 1, 1958