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By Todd M. Ruff

This report summarizes ongoing research at the National Institute for Occupational Safety and Health, Spokane Research Laboratory, in which collision warning systems for surface mining dump trucks are being evaluated. Common accidents involve these large trucks running over smaller vehicles or pedestrian workers. Collision warning systems currently use one of several methods, including radar, radio-frequency-signal detection, or ultrasonic signals, to detect and warn of the presence of an object or person in the blind spots of the mining equipment. Most available systems have not been tested on large off-highway dump trucks. This report evaluates several systems on two sizes of trucks, a 50-ton-capacity truck commonly used in quarries and construction and a 240-ton-capacity truck commonly used in open-pit mines. Tests were conducted to determine false alarm rates, alarm effectiveness, and reliable detection zones for a person and a pickup truck. The results indicate that radar and radio-frequency identification systems show promise for this application and that several of the improved systems are ready for extensive field tests. However, challenges still exist in applying these technologies to large trucks.

Jan 11, 2000

By Robert E. Johnson

1962 was the second year of recovery from the mild 1960-61 recession. The year-to-year gain in constant dollar gross national product, our most comprehensive measure of the country's economic performance, was 6.0 percent (from $447.7 billion in 1961 to $474.8 billion in 1962). The unemployment rate declined from 6.7 percent to 5.6 percent. Although it was a good year, there were still unused resources of labor and capital which implied that the economy was operating below its potential. The year-to-year change in the Federal Reserve Board (FRB) index of industrial production of 7.6 percent masked the fact that more than one-third of the growth took place within 196L The monthly index rose only 4.8 percent during 1962, from 114.3 in January to 117.8 in September. The fact that the economy as shown by the industrial index, rose rapidly in the first half of the year only to remain on a plateau of 119-120 during the second half, led some people to fear an imminent downward turn. This did not occur. Neither production nor consumption of mineral fuels advanced as fast as the total economy. But consumption showed more gain than production, 5 percent compared with somewhat less than 4 percent. Production of both crude oil and natural gas reached new highs while bituminous coal production was the highest in 5 years.

Jan 1, 1963

By Kenneth H. Johnston

This report describes in detail three waterflooding projects and a pressure-maintenance project in Butler and Cowley Counties, Kans., that will be visited on the 1963 annual spring tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the flooding of five oil-producing horizons separately with injection water furnished by two water-treating plants. Discussion of the individual projects includes information on their early history, the source and treatment of the injection fluids, oil production decline curves, and the results of water injection on oil production.

Jan 1, 1963

By Russell J. Foster

Public awareness of, and involvement in, recycling has increased significantly in recent years. Nevertheless, recycling is generally perceived as a new development, and is familiar only in the context of municipal solid waste management. The actual magnitude and scope of metals recycling in the United States have gone virtually unnoticed. Over time, both the quantitative and qualitative aspects of secondary metals recovery and reuse have changed substantially, while the attendant regulations have become increasingly stringent. This U.S. Bureau of Mines report examines trends and developments in major metal demand and recycling, and analyzes the possible impacts of regulations with regard to recycling activities.

Jan 1, 1994

To improve the air quality in large-opening stone mines by developing better ventilation techniques, including appropriate fan selection in conjunction with air-coursing methods. Background Stone mines are the most common underground large-entry mines in the United States. Data from the Mine Safety and Health Administration (MSHA) for the year 2000 indicate that there were 162 active nonmetal underground mines in the United States, of which 117 were stone mines. Many underground stone mines are drift mines developed from previous quarry operations. Typically, these room-and-pillar mines have entries that are 20 ft or higher and at least 40 ft wide. These large dimensions lead to a very small ventilating pressure loss, even when significant air quantities move through the mine. This is especially true of drift mine operations where ventilating pressure losses of <0.25 in w.g. are common. Underground stone mines with shafts that are<200 ft deep typically have ventilating pressure losses that are <2 in w.g. The pressure losses through these mines are much lower than those of a typical coal mine or deep metal/nonmetal mine. Therefore, the ventilation techniques and principles are quite different. In addition, because of new MSHA regulations that limit the concentration of diesel particulate matter, these mines may need to greatly increase their ventilation airflow. Therefore, large-opening mines need a fan that can move large air quantities and operate at low static pressures. There are three fan types for mine ventilation: centrifugal, axial vane, and propeller. Centrifugal fans are uncommon in underground stone mines as they are often associated with mines requiring the highest of ventilation pressures. Axial vane fans are widely used in all types of mining operations. They are the most common fan type currently found in underground large-opening stone mines. However, they typically do not operate at low static pressures with high efficiency. Propeller fans are currently uncommon in underground stone mines. They are designed for low static pressures and large air quantities at higher efficiency. This fan type best suits the ventilation needs in large-opening stone mines?they produce large air quantities at low pressure losses. Mines with air shafts<100 ft long and at least 12 ft in diameter have fairly low mine static pressures and may also benefit from propeller fans.

Dec 1, 2002

By E. C. Tarpley

An acid-extraction procedure developed in Germany for determining mineral matter in coal was investigated by the Bureau of Mines to determine its application to American coals. It was found to be suitable for all ranks of coal from anthracite to lignite if modified slightly for coals containing considerable quantities of calcium compounds, such as calcite or calcium humate. The precision of the method is satisfactory, and the results are probably closer to the true content of mineral matter than those obtained by empirical formulas. The method requires considerably more analytical data than the Parr or approximation formulas but is no more time consuming than obtaining the necessary data for the King, Maries, and Crossley formula (theoretically the most comprehensive empirical formula used). An appendix to this report includes a detailed description of a recommended procedure.

Jan 1, 1959

By Todd M. Ruff

An average of 13 mine workers are killed each year by being run over or pinned by mobile mining equipment. At surface mines, these accidents commonly involve large dump trucks that drive over a smaller vehicle or a person that is in the dump truck’s blind spot. One method of detecting a person or another vehicle in a blind spot is to use some type of sensor technology such as radar or radio-frequency identification (RFID). Researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health tested a number of commercially available and experimental sensors that monitor obstacles in a vehicle’s blind spots. None of the sensors had been previously applied to the specific problem of rigid-frame surface mining trucks. This report documents the procedures and results of tests conducted after RFID and radar systems were mounted on a 50-ton-capacity dump truck. It was determined that both RFID and radar technology show promise for detecting obstacles in the blind spots of mining equipment; however, more development work is needed to meet the unique requirements of mining equipment and the mine environment.

Jan 1, 2000

By N. Kyriazi

The U.S. Bureau of Mines subjected the CSE SR-lOO self-contained self-rescuer (SCSR) approved by the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) to a series of laboratory treatments designed to simulate various environmental conditions in underground coal mines. The tests were designed to predict the ability of the self-rescuers to withstand those environmental stresses without causing a decrease in wearer protection. The apparatus were heated to 710 C for 48 h, cooled to -450 C for 16 h, vibrated for 9 h, and dropped 1 m on each axis. A critical concern was internal damage to an apparatus, without any obvious external signs, that would cause it to malfunction or seriously degrade its performance. Carbon dioxide (C02) levels in apparatus with combined treatments were higher than in apparatus with individual treatments and untreated apparatus. The higher levels remained within safe limits, however. None of the treatments caused venting of the small oxygen cylinder that provides starter oxygen. Some bottles were found to be empty because of manufacturing defects in the burst disks. This problem was corrected in later models. The heat treatments did make the case ends more difficult to remove and the breathing bag sticky and subsequently more difficult to unfold. An apparatus that was dropped and vibrated had a broken desiccant bag that released some of its contents which compromised the seal of the relief valve. The case was dented from the drops. As with the first-generation self-rescuers, if there is visible damage to the case of the apparatus, the apparatus should be considered to be internally damaged and must be removed from service.

Jan 1, 1990

By Gabriel S. Esterhuizen, Jarek Jakubec

In 2000, Laubscher’s Mining Rock Mass Rating (MRMR) classification system was updated and published. The new system brought a few fundamental changes that were in direct response to the challenges and problems encountered when applying the classification system in the mining environment, specifically caving operations. The fundamental changes introduced into the MRMR system in 2000 were the abandonment of the Rock Quality Designation (RQD) as an input parameter, accounting for healed and cemented joints, and the concept of rock block strength. The objective of this paper is not to discuss the role and usefulness of classification systems; the fact that classification systems are widely used in every stage of mining projects speaks for itself. This paper discusses some of the experiences gained with the MRMR 2000 system in various mining projects and shows how the changes to the system have resulted in improved assessment of rock mass conditions. Issues related to core logging for rock mass assessment are also presented.

Jan 5, 2007

By A. Visnapuu

Excessive noise and high vibration are inherently associated with equipment used in the mining, extraction, and processing of mineral resources. High vibration degrades structural components, often leading to catastrophic failure and loss of productivity, and excessive noise can result in permanent hearing loss. In order to foster efficient utilization of the Nation&apos;s mineral resources and minimize occupational hazards associated with mineral processing, the Bureau of Mines investigated the relationship between the microstructures of carbon and alloy steels and cast irons and their damping capacities (ability to absorb vibration). Researchers measured damping capacity and other properties and investigated the effects of carburizing, spheroidizing, and annealing. The investigators found that in carbon and alloy steels, rounded colonies of fine-grained pearlite in a ferrite matrix correlate well with low damping capacity. Steel microstructures that exhibit sharp-faceted pearlite in ferrite matrix and partially or fully spheroidized cementite in ferrite show considerably higher damping. In cast irons, the lowest damping capacity is associated with nodular graphite microstructure, and the specific damping capacity (SDC) increases as the graphite micro-structure progresses from nodular to compacted to flake. Predominant ferrite in cast irons is also associated with good damping. SDC data are presented for selected carbon and alloy steels and cast irons.

Jan 1, 1987

By I. L. Nichols

The Bureau of Mines is investigating vanadium recovery from various domestic resources. A low-grade carnotite ore sample containing 0.34 pct V20S and 0.04 pct U30S was leached, and the results were compared with those of similar leach tests using a mill-grade sample containing 1.26 pct V205 and 0.19 pct U308. Experiments on the two ore samples included agitation leaching, pugging, salt-roast leaching, and autoclave leaching. None of the leaching methods investigated showed any significant advantage over another except autoclaving, which reduced the leach time but at the expense of greater acid consumption. Typical of the experimental results attained are the data gathered from the agitation leaching tests. Agitation leaching of the mill-grade ore with 100 lb/ton H2S04 resulted in extractions of 94 pct U308 and 33 pct V205. To increase the vanadium extraction from 33 to 91 pct required concentrations of 300 lb/ton H2S04 and 10 lb/ton NaC103. Complementary agitation leach tests on the low-grade ore required 200 lb/ton H2S04 to extract 94 pct U308, and 300 lb/ton H2S04 and 10 lb/ton NaC103 to extract 90 pct V205.

Jan 1, 1983

By R. A. Meyer

A table that greatly simplifies determination of metastable transitions in mass spectra has been prepared. All the mathematically possible metastable transitions of any compound whose molecular weight lies between 26 and 150 can be determined from the table without calculation. The method of utilizing the table is described, using selected peaks from the spectrum of normal butane for illustration. In the mass spectrometer, ions are formed in the isatron and accelerated through a series of slits. Most of these ions reach the collector without further change, but a few dissociate in transit to form new ions. These ions appear in the mass spectrum at neither the mass--to-charge ratio (m/e) of the original ion nor that of the new ion. A formula that relates the appearance of these new ions to the ion from which they were formed is: [ ]

Jan 1, 1957

By Kenneth M. Maas

The Bureau of Mines inventoried all lands in Alaska to determine the availability of land for oil, gas, and coal leasing. Acreage for onshore oil, gas, and coal basins was digitized as was land ownership data. Regulatory policy concerning oil, gas, and coal leasing for various government agencies and private concerns was determined. Oil and gas basins underlie 79.4 million acres of Alaska&apos;s 378 million acre landbase. Federal agencies manage 44 million of these acres. The Bureau of Land Management is the lead agency for most oil and gas leasing on Federal lands. Lands have to be specifically opened for oil and gas leasing to be available. The state of Alaska manages 21.1 million acres underlain by these basins. More than 80 percent of this acreage is available for resource development. Native corporations manage the remaining 14.3 million acres of favorable oil and gas land. Coal basins underlie nearly 51 million acres of Alaska. Of this land, 26.4 million acres are under Federal jurisdiction. The state manages 17.3 million acres of land underlain by coal basins. Nearly 7.3 million acres of favorable coal lands are managed by Native corporations.

Jan 1, 1991

By Christopher Mark

Perhaps the most significant development in coal mine ground control during the last century was the introduction of roof bolting during the late 1940’s and 1950’s. From an engineering standpoint, roof bolts are inherently more effective than the wood timbers they replaced. Roof bolts promised to dramatically reduce the number of roof fall accidents, which then claimed hundreds of lives each year, and they were initially hailed as “one of the great social advances of our time.” Roof bolting also emerged at a time of rapid technologic transformation of the coal industry, and greatly accelerated the transition to trackless, rubber-tired face haulage. The U.S. Bureau of Mines quickly became the new roof support’s strongest advocate. Some state agencies and miners were skeptical at first, but nearly everyone was soon won over. Case histories were reported showing that roof falls could be largely eliminated while productivity increased dramatically. Little wonder that, in the words of one contemporary observer, “roof bolting has been adopted more rapidly than any other new technology in the history of coal mine mechanization.” Yet by the end of the 1950’s, it was clear that roof fall fatality incidence rates had actually increased. It would be another decade before the superior ground support provided by roof bolts would clearly save lives. The story of how roof bolting was implemented by the mining industry, but took so long to live up to its promise, is a fascinating example of the interaction between economics, technology, regulation, and science. It still has important lessons for today.

By Avery H. Reed

[The Bureau of rides is making a general study of the occurrence of the Clinton red iron ores of Alabama. In the course of this study, it developed that the iron-ore seams of the Woodstock and Bucksville areas were virtually unexplored., and the nature and extent of the ore deposits were undetermined. As a part of the work of the project, the Bureau investigated the occurrence of red iron ore in the .areas. Eighty-four channel samples, representing 317.6 linear feet, were taken from l2 locations along the outcrop of the red iron-ore seams, Ten diamond-drill holes, amounting to 3915.5 linear feet, were drilled. In these areas, commercial- and marginal-grade ores of minable thickness have been shown. It is estimated that 4,500,000 tons of indicated ore and 6,700,000 tens of inferred commercial-grade ore averaging 5.1 feet thick, 47.6 percent Fe, 26.1 percent insoluble, 0.1 percent CaO, and 0.04 percent P; 7,200,000 tins of inferred marginal grade ore averaging 6.1 feet thick, 36.2 percent Fe, .35.0 percent insoluble, 3.9 percent CaO, and 0.14 percent P; and 18,500,000 tons of ferruginous sandstone averaging 12.2 feet thick, 19.2 percent re, 50.1 percent insoluble, 9.6 percent CaO, and 0.14 percent P are present in the areas.. All tonnages are estimated as gross tons of recoverable ore in place, based&apos; on 65-percent mining recovery. In accordance with established policy of the Bureau of Mines of publishing factual data as soon as possible after completion of field work, this description of the Woodstock and Bucksville areas is presented. As soon as work is completed in other areas additional reports will be prepared.]

Jan 1, 1953

By Thomas Fraser, E. A. Holbrook

The data in this bulletin were obtained during an investigation of screening practice by the University of Illinois engineering experiment station and the United States Bureau of Mines under a cooperative agreement between them and the State of Illinois Geological Survey Division. Earlier work on this subject includes a study of the general practice of coal preparation in Illinois, made in 1914 and published in 1916/ and an investigation of Illinois coal-w.ashing methods, results of which were published in 1912 in a bulletin 2 that contained complete information on the methods then in use for sizing washed coa 1.

Jan 1, 1925

By J. D. Noll, S. E. Mischler

Measurement and sampling of diesel particulate matter in mine air presents a challenge due to the complexity of the diesel aerosol. The results of a series of tests carried out by the National Institute for Occupation Safety and Health, Pittsburgh Research Laboratory, in an underground mine were used to evaluate several measurement methods that are currently used to characterize particulate matter emitted by diesel-powered equipment. This paper presents an overview of these techniques and examples of the results along with a discussion of the advantages and information gained by each technique. The measurement methods discussed include particle size measurements using a scanning mobility particle sizer, total particulate matter measurements using a tapered elemental oscillating microbalance, a size selective sampling method for workplace and personal exposure assessment and a size-selective high volume sampling method for carbon analysis.

By V. T. Dow

This report describes construction details and methods used in driving the 5490 tunnel at the Kennecott Copper Corp, property, Bingham, Utah. The tunnel will provide railroad access to the world-famous open-pit copper mine at the projected 5490 level. This publication is one of a series prepared by the Bureau of Mines to depict mining operations and techniques in various mining districts in the United States. Utah Construction and Mining Go. (formerly Utah Construction Co.), contractor on the tunnel project, began work during September 1956 and completed the project in February 1959. The tunnel is 18 feet wide, 24 feet high, and about 18,000 feet long, It will accommodate a railroad locomotive on standard- gage track. With the exception of the last 1,700 feet, the tunnel is supported by steel sets embedded in concrete lining. The 1,700-fact segment of the tunnel is supported by timber sets that will eventually be removed as the pit is deepened.

Jan 1, 1962

By Karl R. Becker

A variety of commercial detonators (fuse type and electric instantaneous and delay types) were subjected to impact and thermal stimuli to determine initiation stimulus levels and the dominant parameters in resistance to initiation. In the impact trials the detonators were impacted along their length to find the most sensitive region; threshold initiation limits obtained for these regions ranged from 3.47 to 20.82 joules (2.6 to 15.4 ft-lb). The friction sensitivity of the explosive component was an important parameter in determining sensitivity; various construction features of nonexplosive components played a role as well. In the thermal sensitivity trials, the detonators were heated from ambient to 100° C at an average rate of about 1.0° C/min, and thereafter at 0.5° C/min until they exploded; the explosion temperatures observed ranged from 121° to 188° C. These temperatures correlated quite well with the reaction temperatures of certain characteristic explosive components used by different manufacturers. The data also indicated an effect of confinement on explosion temperatures of detonators.

Jan 1, 1975

By E. Shekarchi

A year after the Soviet Union invaded Afghanistan and replaced President Amin with their choice, President Karmal, Afghanistan remained in turmoil. In some respects, the political and economic situation in Afghanistan was no better by the end of 1980 than it was preceding the December 1979 invasion. The Government faced widespread and growing alienation and resistance, virulent factionalism within the ruling party, and an acute shortage of material. The mining sector of the country did not fare better either; the only raw material produced in a significant amount was natural gas, which was exported mainly to the Soviet Union. No statistics on production of other minerals and materials were available by yearend. Most of Afghanistan&apos;s gas production was from the Hodja-Gugerdag Field, southeast of Shibarghan. The gas flow from this field had been about 300 million cubic feet per day since 1961. An estimated 230 to 250 million cubic feet per day of Hodja-Gugerdag&apos;s production was moved by pipeline across the Amu-Darya River into the Soviet Union. Most of the remainder was transmitted eastward to a 105,000-ton-per-year fertilizer plant and an electric power station built near Mazar-i-Sharif with Soviet assistance. After the Soviet invasion, the second gasfield, Djar-Kuduk, in the Shibarghan area, was brought under production. This field, which will produce about 200 million cubic feet per day, consists of four gas zones in the Jurassic and lower Cretaceous zones between 3,000 and 8.500 feet deep. The gas has a high hydrogen sulfide content, with considerable carbon dioxide, A new treatment plant was built at Djar-Kuduk by Soviet technicians under a turnkey contract at the end of 1980. It is believed that most of the Djar-Kuduk&apos;s initial flow will be sent to the Soviet Union.

Jan 1, 1982