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By Charles L. Kimbell

Available statistics on 1989 worldwide consumption of selected nonfuel minerals shown in table 5 show increases for 11 of 14 listed nonfuel mineral commodities with 1 unchanged from the 1988 level, a departure from the pattern of the past 2 years, in which each of the listed commodities registered gains. The 1989 results, however, were better than those for 1986 when only seven listed nonfuel mineral commodities recorded gains with one un- changed from 1985. Consumption of the two ferrous metal raw materials listed advanced as functions of increased output of pig iron and crude steel. The increase in iron ore consumption exceeded the increase in iron ore output, suggesting a slight drawdown of world iron ore inventories. The estimated in- crease in iron and steel scrap consumption was slightly greater than the minuscule increase in world steel production, but it is believed that there was little change in the ratio of iron ore to scrap in steel plant feed on a global basis.

Jan 1, 1992

By William H. Schiffbauer

This paper details the computer hardware and software integrated to provide computer-assisted control and monitoring of four different coal mining machines. The backbone of each system is a U. S. Bureau of Mines integrated distributed microcomputer control network called BOM/NET. The network provides connections for intelligent sensors and systems that provide for navigation, diagnostics, and computer control. Many different computer systems using various operating systems (including RMX I, UNIX, VXWORKS, DOS and DCX51) have been connected to the network and each have had complete network functionality. A description of the network's integration to Joy' 16CM, a Joy 14CM, a Jeffrey 102, continuous mining machines, and a custom built auger machine is provided. The networks for the Joy 16CM, the Joy 14CM, and the Jeffrey 102 have been installed and extensively tested at the Bureau's surface test facility. The Jeffrey 102 system has also been tested in a highwall coal seam. The Joy 14CM will soon be tested underground.

By H. B. Salisbury

The Bureau of Mines conducted research to determine if low-grade California chromite ores could be beneficiated to produce products suitable for commercial use. This research is part of a Bureau goal to provide technology capable of using low-grade domestic ores to meet emergency demands of the Nation for metals and minerals and in particular those minerals, such as chromite, which are considered critical. Two ores from California were ground and treated using gravity concentration and magnetic separation techniques. An are from Auburn in central California, assaying 2.5 pct Cr203, was treated by tabling and magnetic separation to yield a nonmagnetic product containing 44.7 pct Cr203 at a recovery of 36.4 pct. Core drilling samples from the Seiad Creek area of northern California, assaying about 6 pct Cr203, were upgraded by tabling to yield a concentrate containing nearly 50 pct Cr203 with a recovery of 50 pct. Both products are suitable for metallurgical and/or chemical use.

Jan 1, 1981

By Harold W. Lipper

Helium production and shipment reached new peaks in 1.361. The Bureau of Mines produced 727 million cubic feet, 13 percent more than the 1960 record, and shipped 552 million cubic feet, 16 percent more than the 1960 record. Production exceeded demand for the third successive year, enabling the Bureau of Mines to add 174 million cubic feet to the volume stored underground for future use. At the end of 1961, the total volume of helium in underground storage in the Clifside gasfield was 44-7 million cubic feet. Contracts to implement a long-range helium conservation program were completed with four companies, obligating all the contracting authority of $47.5 million a year made available by the Congress. The four companies will finance, build, and operate helium extraction plants to recover from natural gas an annual average of 3.1 billion cubic feet of helium that would ordinarily be wasted when the helium-bearing natural gas is used for fuel.

Jan 1, 1962

Improve ground control in longwall gate entries by developing a practical method for evaluating longwall pillar designs. Background Longwalls have emerged as the most important technology to be applied to underground mining since the continuous mining machine. Longwall mines currently produce more than 30 pct of all the underground coal mined in the United States, up from less than 5 pct just 15 years ago. Safe longwall mining depends on maintaining ground control in the gate entries, the lifelines that provide access to the longwall face. In multientry retreat mining as practiced in the United States, rows of chain pillars are left to protect the gate entries (see figure 1). Chain pillars are subject to severe and complex abutment loads during the process of longwall panel extraction. The design of these pillars is often the single most important element in gate entry ground control and has been the subject of intensive Bureau of Mines research.

Jan 1, 1991

Perform laboratory tests to measure the vibration attenuation characteristics of off-road vehicle operator seats for various types of seat suspensions, cushions, and seat adjustment settings. Background A study was conducted by the U.S. Bureau of Mines to determine the probability of whole-body vibration (WBV) exposure for a large class of off-road machinery operating in surface coal mines. The study determined that mere than 40 pct of off-road equipment operators were exposed to WBV exceeding the standard fatigue-decreased-proficiency (FDP) level defined by the International Standards Organization in its guideline ISO standard 2631. The tire-terrain interaction of a moving vehicle generates vibrations that are transmitted through the ve¬hicle suspension, cab mounting, and seat. The final point of transmission of vehicle vibration to the operator is through the scat. A seat that provides good vibration isolation and allows good vehicle control is of prime importance to operator safety and health.

Jan 1, 1993

Provide sound battery safety guidelines for mine workers who maintain mobile surface mining equipment. Approach Battery-related accidents account for about 5 percent of all nonfatal disabling injuries in coal and metal nonmetal surface mines. These accidents occur despite the fact that appropriate battery safety technology (maintenance-free batteries, cable removers, fault detectors, hot-jumping systems, etc.) exists. Mine operators are not always aware of the safety measures that could be taken because this safety information is widely scattered in numerous unrelated technical reports, vendor brochures, and journal articles. A literature search of these reports and a review of relevant industry standards, handbooks, and references on battery safety, followed by discussions with mining company and MSHA personnel, provided the Bureau of Mines with the background necessary to develop procedures for proper and safe battery usage. These procedures were condensed and written in nontechnical language to serve as guidelines in assuring battery safety during maintenance of mining equipment.

Jan 1, 1986

By John C. Machisak

THIS CHAPTER of the Minerals Yearbook relates to employment data and injury experience in the metal, nonmetal, and quarrying industries. Combined statistical data on the mineral industries as a whole can be found in volume Ill. Each industry in the chapter is shown separately, and no attempt has been made to combine and show an overall picture. The voluntary reporting of data on injuries and employment by operators of metal and nonmetal mines and quarries has contributed substantially to the promotion of safety in these industries. Data on injury and employment in the clay mining and milling industry are included for the first time. Table 6 contains data for clay mines only for 1955 and for clay mines and mills for 1956. The clay-mill figures are included with other nonmetallic mills in table 5. The information for norunetallic mills was compiled and published for the first time in the 1955 issue of this report.

Jan 1, 1958

By Robert F. Randolph

Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This paper reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Research to reduce these accidents includes improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

Jan 1, 2000

By Harry W. Campbell

U.S. Bureau of Mines investigation; identified no mineral resources or evidence of mining activity in the Sheep Divide RARE II area. A deposit 10 mi (16 km) southwest of the area contains copper and silver minerals in the Triassic Wild Sheep Creek Formation which probably underlies basalt lava flows covering the study area. Abundant basalt in the area can be crushed and used as aggregate, but suitable deposits closer to markets are widely available No sand, gravel, coal, oil, gas, or geothermal resource, were Identified. INTRODUCTION Location and Access The Sheep Divide RARE II area [10 mi (16 km) west of the Snake River] encompasses 7,100 acres (2,800 ha) of the Hells Canyon National Recreation Area in the Wallowa-Whitman National Forest. Enterprise, Oregon, is located 23 air mi (37 (m) west of the area. Peripheral access is provided by the highway from Joseph to the community of Imnaha, Oregon, then south to the study area by the graveled Upper Imnaha Road (fig. 1).

Jan 1, 1983

By David W. Wisecarver

This report describes a tool to engage and/or place a Bureau of Mines type gage to measure borehole deformation in a horizontal , 1½ - inch - diameter , stress relief borehole . The tool was successfully used at a borehole depth of 105 feet . Practical usage up to borehole depths of 200 feet might be realized . The tool was designed to work inside EX- size ( 1½ - inch ID ) diamond - drill drive casing used as drill rod and through which the deformation gage is guided into an EX- size stress relief borehole . Through laboratory experiments it was found that by exercising a reasonable amount of care the deformation gage could be placed at a point within a ± .01 foot distance of a predetermined depth in a horizontal EX- size hole and that the deformation measuring piston or plunger of the gage could be oriented in the borehole within 0.5 ° of a preselected angle of orientation in a vertical plane .

Jan 1, 1964

By L. C. IlsLey

A preliminary investigation has recently been made by the U. S. Bureau of Mines to determine whether or not the ordinary mine- type telephone is entirely safe in gaseous atmospheres . Two well known makes of mine- type phones were purchased for this investigation . It is not conceivable that the current necessary for talking over telephones could ignite gas . However , such phones are provided with efficient magnetos , and it was believed that danger might result from the ringing of the magneto . Again , while this type of phone has been designed to have a certain measure of dust and moisture tightness , evidently it has not been designed as an explosion- proof device . either with regard to cover joints and fastenings or strength of castings . Therefore , the problem was simplified . First it was assumed that owing to the construction of the telephones the gas would penetrate into their interior , and the question was to ascertain whether or not the gas would be ignited from the operation of the magneto .

Jan 1, 1922

Federal lands often contain extensive mineral resources and decisions affecting access to those lands are made with knowledge of the possible minerals-related consequences. Information is provided to the Bureau of Land Management (BLM) in this report for use in preparing environmental impact statements on the Western Mojave Management Area (WMMA) and the Desert Tortoise Priority Habitat (DTPH). To augment U.S. Bureau of Mines (USBM) efforts such as the Mineral Assessment of the Planned Foil Irwin Expansion, Modified Silurian Valley Alternative, San Bernardino County, California which is in progress, and the Economic Analysis of the Minerals Potential of the East Mojave National Scenic Area; California, the USBM studied mineral deposits and estimated the potential impacts of mining in a segment of the California desert; the 8.7-million-acre WMMA, an area which includes the 1.2-million-acre Desert Tortoise Priority Habitat (DTPH). In addition, this information is intended to assist administrators, legislators, and the concerned public in understanding the economic importance of mineral resources in the California desert, especially that portion designated as the WMMA. See figure 1.

Jan 1, 1993

By Donald O. Capstick

In 1981, U.S. Bureau of Mines personnel conducted a survey of claims and prospects in the Wheeler Ridge RARE II area to determine if mineral resources or potential for resources exists at deposits in the area. Results of Bureau of Mines investigations indicate the area contains no identified mineral deposits. However, the geologic setting at the Round Valley Peak Prospect near the center of the study area is considered to be favorable for the discovery of tungsten resources with associated molybdenum and copper. Tungsten deposits, should they be present, would be expected to occur at depth in tactite at or near the calcareous rock-granite intrusive contact. Sand, gravel, and stone deposits in the area are not considered to be resources because equal or better quality material is available closer to major markets. INTRODUCTION The 16,200-acre (6,560 ha) Wheeler Ridge study area is 11 mi (18 km) northwest of Bishop, California, on the eastern flank of the Sierra Nevada range. The John Muir Wilderness adjoins the study area's western boundary (fig. 1).

Jan 1, 1983

1. Data from the Mine Safety and Health Administration (MSHA) indicate that a total of 44,015 employees worked in underground mining locations in 2003, corresponding to 44,778 full-time equivalent (FTE) workers. • Ninety percent of underground employees (n = 39,735) were mine operator employees. • Contractors comprised 10% of all underground mining employees (n = 4,280) and comprised only 5.8% of all underground FTEs. • The majority of underground employees worked for coal operators (73.0%; n = 32,130).

Feb 1, 2005

By Donald P. Tuchman

The U.S. Bureau of Mimes is investigating Fourier transform infrared (FTIR) spectroscopy for on- filter quartz analysis of respirable dust. A custom accessory is described for full-face examination of filters utilizing a large-diameter infrared (IR) beam. The accessory positions samples to match diameters with that of the diverging analytical beam. Sample absorbance is then measured. With nonuniform deposition of dust on collection filters being a major issue for such analyses, this approach is the most direct way to accomplish sample area averaging. The approach is unconventional since it utilizes large-beam geometries instead of the usually desired minimized beam dimensions. The issues and problems involved in the analysis of quartz on a filter matrix are discussed. Absorption bands chosen, light-scattering effects, curved baselines, random noise, interference fringes, and possible solutions to technical difficulties are the topics covered. The more significant findings include a 20-pg detection limit for quartz when the custom accessory is used and minimal occurrence of light-scattering effects at low wavenumbers. The custom accessory performance was satisfactory and merits further work. With continued research, an on-filter method for quartz analysis of respirable dusts seems achievable.

Jan 1, 1992

"A coordinated, integrated research effort aimed at studying the scientific, engineering and medical aspects of the respirable dust problem is underway in the areas of dust generation, dust dispersion and dilution, dust characterization, interaction of dust and lungs, and relationship of seam characteristics to dust generation and mobility. (FIGURE 24) The Center's research program explores these concerns with the objective of refining existing strategies and developing new respirable dust control techniques that are consistent with the dust-lung interaction processes that lead to mine worker disability. The fundamental aspects of this work are applicable to the control of respirable dust problems in both hard rock mines and coal mines and to other dusts such as diesel-generated.Research projects in the Generic Mineral Technology Center for Respirable Dust have effected several improved methods for the preparation and characterization of the dusts needed by these projects. Superior procedures for generating ""standard"" dust samples have been developed and are in regular use in the laboratory. Questions raised during the course of some projects regarding ""stale"" versus ""fresh"" dust have led to the development of sampling techniques where the dust is directly collected in a surfactant. MSHA and CANMET have requested and received information on Center generated software. An equipment manufacturer, TSI, Inc., requesting input on modifying the inlet of an aerosol sampler has been assisted as a result of research that was conducted at the University of Minnesota.The objectives, scope and progress of all the research projects in the Center, in the form of abstracts and reports, have been detailed in Volume 1 of this series. Research papers written by the principle investigators and resulting from the findings of projects (FIGURE 25) and which are funded by U.S. Bureau of Mines grant number G1135142 have been published in Volumes 3 through 6 and Volume 8 of this series. Volume 2 relates the cooperation and interaction of the U.S. Bureau of Mines and the Generic Mineral Technology Center for Respirable Dust in research on the problem of respirable dust in the mineral industries."

Aug 31, 1989

By Timothy J. Orr, Michael J. Beus, Frank T. Duda

The technology to enhance safety and control features for mine shaft hoists is being investigated by researchers at the U.S. Bureau of Mines (USBM). The objective of the research is to prevent injuries and fatalities related to hoist and elevator operations. Monitoring and controlling mine hoisting operations will allow hoist operators, inspectors, and maintenance personnel to increase their awareness of potentially dangerous situations and provide controls for safer operations. Process simulation and visualization software, real-time data sensing, and advanced programming techniques are being applied to this problem. Development of reliable and cost-effective sensors and data acquisition interfaces to monitor hoist loads and detect slack rope conditions is underway. Three-dimensional design software was used to visualize mine hoisting to enhance understanding of hoist operations. Quick Basic and Visual Basic (an object-oriented Windows interface) are being used for acquiring and processing hoisting data. Testing and evaluation of components are underway at USBM testing facilities. The resulting system will allow hoist personnel to assess critical operating parameters, such as hoist position, speed, acceleration, conveyance load, and rope tension.

By Andrew B. Cecala, Robert J. Timko, Alexander D. Prokop

Bag loading and stacking processes are the highest dust-exposure job categories in the metal/nonmetal mining industry.1 To cost-effectively decrease respirable dust levels, the Pittsburgh Research Center of the National Institute of Occupational Safety and Health (NIOSH), formerly of the U. S. Bureau of Mines, designed and tested a system called the Bag and Belt Cleaner Device (B&BCD). [ ]

By S. C. Tadolini, T. M. Barczark

Mines in the western United States have had limited choices for standing support. Wood cribs were often too soft and unstable. The introduction of the Can support in the earl v 1990s provided an effective alternative, (lilt/ it remains the dominant form of tail¬gate support. Water-filled prestressing cells are now used to cap the Can and preload it to provide an active roof load. The Cluster Prop, consisting of three timber wedge props bundled to¬gether; provides more capacity than (m equivalent sized Call support and improves transport efficiency. However the Cluster Prop is less stable and does not maintain a consistent load throughout its loading profile. Pumpable roof supports are another alternative support, but the \' have not been proven in high deformation en¬vironments. This paper compares the performance characteristics o f these various support systems.