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By Lyda W. Hersloff

An environmental monitoring program was established to assess the baseline of parameters which may be impacted by a research and development hydraulic borehole mining operation. During the baseline program, two aquifers were identified at the borehole site with the overlying sand aquifer being distinct from the ore sand aquifer on the basis of radiological parameters. The direction of flow of groundwater was determined to be north 19° west at a rate of 1.82 feet per year. Tests to determine the effect of backfilling the boreholes indicated that using overburden from the open pit mining operation would not significantly increase the radiological consti¬tuents of the ore sand aquifer. Mining measurements of the- radon flux from the borehole indicated that the actual release rate of 0.035 pCi/sec was several orders of magnitude less than the calculated estimate by the Environmental Protection Agency. Finally, a gamma survey conducted at the site indicated that the terrestrial component of background radiation was consistent with that in areas near uranium deposits. The methodology used as well as the supporting data are given in this report.

Jan 1, 1981

By Jesse L. Hoyer

A Bureau of Mines turbomill was evaluated for use in the production of high-purity, ultrafine x-Sic powders suitable for advanced ceramics that could substitute for high-temperature alloys containing critical materials such as chromium, cobalt, and nickel. The effect of milling param-eters, such as type of dispersant, temperature, pH, and gas environment, on the milling of x-SiC was studied. The addition of dispersants improved the grindability of x-SiC. Of the six dispersants studied, the best results were obtained with Mara-sperse N-22. Grinding efficiency was also increased when the x-SiC was milled in a basic slurry and at elevated temperature. Gas environments did not appear to affect grinding of x-SiC. Optimum grinding efficiency was obtained at 50° C in a slurry at pH 9.5 with Marasperse N-22 as the dispersant. Under these conditions, minus 100-plus 200-mesh x-SiC was ground to 80 pct less than 1 um in 4 h.

Jan 1, 1987

By Danny Riley, Brian Curry, Sandya Govindaraju, James Bain

Hand arm vibration syndrome (HAVS) affects industrial workers exposed to long term hand-transmitted vibration from powered-tools. Peripheral neuropathy is a major component of the symptom complex of HAVS. Long term exposure to vibration causes myelin damage in peripheral nerves and reduces nerve conduction velocities in rats1. This study addresses the effects of acute vibration at constant acceleration of 49 m/s2 on myelinated fibers in peripheral nerves in Sprague-Dawley male rats using the ‘rat-tail vibration model,’ which simulates hand-transmitted vibration2. Methods Male Sprague-Dawley rats (~300 g) were assigned to vibration groups: 1 hr continuous vibration at 60 Hz; 4 hr continuous exposure at frequencies of 30, 60, 120 or 800 Hz; immediate and 24 hr following a 4-hr cumulative exposure of continuous and intermittent vibration at 60 Hz. Unanesthetized rats were restrained in cages on a nonvibrating platform with their tails placed on a vibrating stage accelerated by a B&K motor type 4809 and vibrated. Intermittent vibration was delivered in bouts of 10 min vibration alternating with 5 min rest periods repeated over 6 hr. Sham controls were restrained without vibration. After vibration exposure, the rats were anaesthetized, and the ventral nerve trunks from the proximal tail segment 7 were fixed in glutaraldehyde, embedded in epon-araldite and sectioned at 0.5 µm thickness and stained with toludine-blue for morphological quantitative analysis. The total number of myelinated axons in each cross-section of the nerve was counted using the Image J software. Myelin damage was identified by focal increase in area and intensity of toludine-blue staining and unraveling of the myelin sheath. Statistical analysis for comparing sham and the different vibration groups was done using Dunnett’s test. Animal treatment and all surgical procedures were approved by the institutional review board and compiled with the Laboratory Animal Welfare Act. Results The rats tolerated continuous vibration very well and exhibited no behavioral signs of stress. When exposed to intermittent vibration, there was increased vocalization, a startle reflex at the beginning of each bout of vibration, deposition of porphyrin around the eyes and transient hypersensitivity to touch.

Jan 6, 2006

By J. F. Neill, O&apos

The manganiferous schists occurring in the vicinity of Kings Mountain, North and South Carolina, suggest significant tonnages of potential submarginal ores. Although some reconnaissance work in connection with these deposits has been reported, no recent information has been published. Evaluation of the schists as a possible domestic manganese resource has not always adequately considered the fact that the manganese content occurs quantitatively both as oxide and as the silicate, spessartite. The Bureau of Mines investigation herein reported includes preliminary studies to indicate the extent of manganese oxide mineralization and to deter-mine the amenability of the material to sulfur dioxide leaching. The field reconnaissance studies suggest a resource containing in one area an average of 6.4 percent manganese as oxide. The procurement of depth information was beyond the scope of the investigation.

Jan 1, 1962

By Paul J. Remington

The field data gathered as part of the measurements described in Volumes I and II were re-analyzed in the low frequency regime (.1 Hz to 1 Hz) where motion sickness normally occurs. These data were compared co the international standard ?ISO 2631 Addendum 2: Evaluation of exposure to whole body z-axis vertical vibration in the frequency range 0.1 to 1.0 Hz." For both underground mining machines and surface mining machines the results showed that one would not expect motion sickness to .be a severe problem. New field data were gathered on the vibration reduction performance of various seat designs found on surface coal mining machines. The vibration during normal operation was measured on the seat using the standard seat pad accelerometer package described in the previous two volumes and simultaneously on the floor of the machine at the base of the seat. Preliminary indications are that the so-called high performance seats used for operator vibration reduction do not offer significant improvement over conventional seats.

Jan 1, 1984

By Eric E. Cather

In 1984 and 1986, at the request of the U.S. Forest Service, the U.S. Bureau of Mines conducted a mineral appraisal of the 315,000-acre Lemhi Range study area. This area is located in Lemhi and Custer Counties, about 25 mi south of Salmon, Idaho, and is in the Northern Rocky Mountain physiographic province, Topography is generally rugged with elevations ranging from 5,600 ft to about 11,350 ft above sea level. Since the 1880's, approximately 500 mining claims have been located within the study area; about 400 were current at the time of this investigation. Also, part or all of 12 patented mining claims are in the study area. During Bureau field work, forty-four mineralized sites were examined. The sites had been explored by 80 adits, 14 shafts, and about 140 pits and trenches. At least five properties in the study area have had significant production; the adjacent Mohawk, Grace Phelan, and Snowbird claims had a combined total of 136,000 oz of silver and 67,000 lb of lead; production at the Brown Bull was about 14,800 oz of silver and 115,000 lb of lead; the Portland mine yielded an unrecorded amount of silver. The Hilltop mine, located a few hundred feet outside the study area, produced 125,000 oz of silver, 2.7 million lb of lead, 87,000 lb of zinc, and 62,000 lb of copper from mineralized zones that might extend into the study area. More than 10,000 lb of copper were produced at the Blue Jay mine from workings located about 1,000 ft outside the study area. The Bureau of Mines investigation did not reveal the presence of identified resources in the study area. However, several areas contain mineralized sites and are known occurrences. Some of these warrant additional work to further delineate the mineralization and possibly determine identified resources.

Jan 1, 1988

By Donald E. Redmon

This Bureau of Mines report examines the injury experience in the quarrying industry For the years 1966-67. Twenty-eight tables for each year are presented in which disabling work injuries are summarized by department, source of injury, extent or disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

The selective placement of coal stripmine overburden is examined. Physical and chemical properties of spoil detrimental to revegetation and groundwater are detailed. The United States is divided into regions or similar problems. Five mining methods already used in the industry, that are capable of selectively handling waste are examined in detail. Technical and economic comparisons are made for the systems when applied to realistic mine settings. The same analysis is conducted for five novel methods capable of selectively handling waste. Comparisons are made between novel and existing methods. Suggestions for new and modified equipment are outlined. Recommendations for further research are provided. This volume contains all Appendices to the report.

Jan 1, 1981

By T. G. Donnelly

This final report summarizes the prototype development and testing of an air curtain respirotory protective device under Bureau of Mines Contract HO122087. The air curtain respiratory protective device, as part of a miner?s hat, provides protection for the underground mining machine operator against inhalation of dangerous amounts of respirable coal dust. Major components of the air curtain respiratory protective device are: 1) a modified miner hat incorporating an air curtain jet manifold from which the protective air curtain emanates, 2) a motor blower which supplies the air for the air curtain, 3) a filter element to remove the particulate material from the air used for the air curtain, and 4) the hoses and coupling used to duct the filtered air from the motor blower to the modified miner's hat.

Jan 1, 1973

By Claud Johnson, Kristine M. Krajnak

Vibration transmitted to the upper limb by the chronic use of hand tools can result in cold-induced vasospasms finger blanching and cyanosis, similar to that seen with Raynaud’s phenomenon (4). These vasospasms, commonly referred to as vibration white finger (VWF), are in part the result of an increased sensitivity of peripheral arteries to the vasoconstricting effects of norepinephrine (e.g., (1-3)). However, alterations in vasodilating factors could also contribute to vasospasms. The goal of these studies was to determine if exposure to a single bout of vibration alters concentrations of the vasodilator, nitric oxide (NO), in a rat tail model of vibration. To determine if vibration exposure alters NO, we exposed animals to a single bout of vibration and measured concentrations of the synthetic enzymes, nitric oxide synthetase (NOS)-1 and NOS-3 in the ventral tail artery. We also directly assessed arterial concentrations of NO using a nitrate/nitrite assay. Methods General apparatus. Animals were placed in Broome-style restrainers, and their tail was secured to a vibrating or stable platform. Rats were exposed to a single 4 h bout of tail vibration (125 Hz, acceleration of 49 m/sec2 r.m.s.) or restraint control. Animals were euthanized with an overdose of pentobarbital (100 mg/kg) and the ventral tail artery was dissected and frozen. Experiment 1: Male Sprague Dawley rats (6 weeks old, n = 32) were used for all exposures. All animals were maintained in AAALAC accredited facilities, and all procedures were approved by the NIOSH Animal Care and Use Committee, and were in compliance with the CDC Regulations for the Care and Use of Laboratory Animals. Animals were euthanized 1 or 24 h after the completion of the exposure. Western analyses were performed on total proteins (80 µg/lane) isolated from the C16-18 artery segments. Band densities were detected by chemiluminescence and quantified using Scion Image, and analyzed using 2-way ANOVAs. Experiment 2. Nitrate/nitrite concentrations.. Male Sprague Dawley rats (n = 24, 6 weeks of age) were maintained and exposed as described above. All animals were euthanized 24 h after the exposure and the ventral artery was collected. Nitrate/nitrite concentrations were measured in ventral artery tissue homogenates using the nitrate/nitrite colormetric Assay Kit (Caymen). Results Analyses of band densities revealed that there was an effect of time (F(1, 17) = 6.03, p < 0.03) on NOS-1 protein in arteries exposed to vibration, with NOS levels being lower in arteries collected 24 h after the exposure than arteries collected 1 h after the exposure. Although NOS-1 proteins concentrations were slightly lower in control arteries collected 24 h after an exposure than arteries collected 1 h after exposure, post-hoc contrasts indicated they were not significantly different than 1 h controls. In contrast, NOS-1 band densities from arteries collected 24 h after the exposure were lower than those collected 1 h after the exposure (p < 0.01; Figure 1). NOS-3

Jan 6, 2006

By C. Froger

Since its creation in 1950, the Centre d&apos;Etudes et Recherches des Charbonnages de France at Verneuil-en-Halatte (Oise) has been conducting many investigations concerned with airborne dust measurements, particularly in underground mines. The work has resulted in the development, a few years ago, of a new process of dust sampling, whereby the airborne dust particles are collected by a rotary filter of polyurethane foam rotating at high speed within 8 housing.

Jan 1, 1973

By C. B. Manula

This report is volume 4 of at. eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment: The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,&apos; and ventilation. This volume of the final report describes the Roof Support subsystem of the Master Design Simulator. This model is based on popular roof support practices for different geological environments with related restrictions imposed by the Coal Mine Health and Safety Act of 1969. From geological sections, the model determines the anchor horizon for roof bolts and the density of roof support necessary. The roof support subsystem is tied to both the geology and reserves subsystem and the production subsystem of the Master Design Simulator, but can also operate as a free standing model. Several case studies are presented showing the application of the model. A detailed user&apos;s manual, including a program listing, is presented in the appendices.

Jan 1, 1974

By Bryan R. Carmenati

This report documents the need for formal health and safety, and equipment operations training in the mine construction industry. The outlines, objectives, and training texts were developed based on the recommendation of needs of mine construction personnel, and those of Dames and Moore (Safety Analysis of Shaft Sinking operations, 1977) and Kinton, Inc. (A Training Program for Conventional and Raise Drill Construction Personnel; Phase I, 1979). The training material samples contained herein (and under separate cover in its entirety) are designed to improve the safety and production of those in mine construction. An instructor-directed presentation is recommended. The results of the study are presented in the Findings and Recommendations section of this report.

Jan 1, 1982

By P. A. Croce

A total of 17 mine gallery fire tests (23 including sub-tests) were completed during this report period (10/1/76 - 11/30/77), directed at identifying a hazardous timber-set fuel-loading in a mine passageway that is otherwise free of combustibles. Results of these initial tests show that the capability of a particular fuel loading for propagating a fire is dependent upon the imposed ventilation air velocity and the ignition intensity, although this dependency needs to be better defined. It is also apparent that care must be taken when relating gallery test fire behavior to actual mine fire behavior, because of the restrictive length of the gallery. Present data indicate that some modification to the instrumentation scheme may be advantageous before proceeding with future tests.

Jan 1, 1978

By P. L. Woolf

Blast furnace coal injection tests conducted by the Bureau of Mines in cooperation with a consortium of 22 steel companies in 1963-1964 are described. These tests were part of a program of extensive investigation of auxiliary fuel injection in the Bureau&apos;s experimental blast furnace located at Bruceton, PA. Seventeen coal tests are described on various coals ranging from anthracite to subbituminous. Factors affecting maximum rates of injection were studied. These included coal size, coal type, and oxygen enrichment. The effect of high sulfur content coal and the means to control metal sulfur were investigated. An epilogue briefly describing the commercial experience with coal injection from 1960 to the present has been included.

Jan 1, 1985

By Richard Rittenhouse

This program was to develop a new base line system for automated continuous room and pillar type mining. The primary requirement estab¬lished for this machine is that the machine be capable of mining and bolting simultaneously. Additionally, this machine was to provide temporary and permanent roof control, have a productive - full - face semi-automatic mining system, leave a clean entry outby the machine, provide maximum operator protection, provide effective dust suppression and provide air scrubbing to restrict respirable dust to permissible levels. The machine has effectively demonstrated the ability to mine and bolt simultaneously. Additional above ground operation, testing, and time studies are recommended to further verify the machines abilities. Design improvements are recommended for future generation AES machines. These relate to marginal design areas such as side loading on vent duct lift cylinders, etc., that will not impair additional testing of the existing machine.

Jan 1, 1983

By Richard J. Bielicki

This Bureau of Mines study estimates the number of major pieces of coal- mining equipment that will be required to produce 950 million tons of marketable coal in 1980 and 1.2 billion tons in 1985. The coal tonnages were projected in the intermediate coal supply scenario of Project Independence Blueprint (PIB). The equipment projections were determined by consideration of historical trends and by evaluation of information from equipment manufacturers and mining companies. The ability of the manufacturers to meet the projected equipment demands was also determined. It was concluded that equipment supply offers no presently discernible constraint to mining 1.2 billion tons of coal in 1985. A shortfall in projected production for the intervening years, however, is probable owing to anticipated shortages of draglines.

Jan 1, 1976

By C. W. Morris

This Final Report describes the major technical activities that were accomplished to produce a comprehensive continuous miner training system (CMTS) for coal industry utilization. The primary product of this program was a continuous miner part-task trainer. It is composed of an interactive computer graphics system combined with the operating controls of a continuous mining machine mounted in a simulated cab. The cab contains an audio system for reproducing continuous miner operational sounds. The trainer is supplemented with a complete set of cognitive materials that provide instruction in the operation, safety and health of continuous miner operations. A complete summary of the field test and evaluation of the CMTS is provided along with a set of recommendations for further training program refinements, expansions, and utilization.

Jan 1, 1982

By R. Stefanko

This study concerns itself with the effects of diesel exhaust on mine ventilation systems. The approach here consisted of the development of mathematical models for emissions, dilution, and dispersion of gaseous pollutants from diesels. The general scheme was to use partial differential equations to predict concentration growths. Specifically, the following situations were modeled: 1. A single stationary diesel engine working in a single roadway. 2. A single diesel engine moving with uniform velocity in a single roadway. 3. Multiple diesel engines moving continuously in a cycle in a roadway with appreciable leakage. 4 Multiple diesel engines moving continuously in a cycle in a roadway with little or no leakage. 5. Multiple diesel engines moving randomly in a roadway with uniform air velocity.

Jan 1, 1974

By L. A. Morley

Volume IV of the final report examines the problem of indirect contact of overhead high-voltage power lines by mining personnel. This refers to the contact of energized lines by workers through some intermediate conductor such as a metallic tool or a piece of high-reaching mobile equipment, thus the term "indirect contact." The shock hazard presented by such contact has been a major cause of electrical fatalities associated with mining operations. The report volume is divided into three major areas. The first gives a general background of overhead lines, basic characteristics, and associated hazards, and continues to describe presently used techniques and devices which attempt to alleviate the contact problem. The second area narrows the discussion to the mining industry by presenting a detailed analysis of 39 overhead-line contact accidents in mining since 1970. The third major section uses the information from the first two areas to formulate recommendations to prevent these accidents and subsequent electrocutions at mining operations.

Jan 1, 1982