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By W. L. Cooley

A significantly different method of evaluating mine ground system safety is investigated. The method measures touch and step potentials around ground beds and grounded equipment resulting from a series of extremely small simulated faults. The values are then scaled for a full-scale fault. The method should be particularly useful for large ground beds and under conditions where the ground bed cannot be isolated from the rest of the ground system in order to make traditional ground bed resistance measurements. Instrumentation for making the alternative measurements is evaluated under rigorous field conditions. A step-by-step procedure is proposed for evaluating a surface mine ground system. This procedure was subject to several field tests at eastern metal/non-metal mines. The final evaluation procedure is written as a stand-alone document for use by MSHA inspectors and mine operating personnel, and is included as an appendix to the report. The authors conclude that the procedure is effective in evaluating ground system safety and recommend that it be further evaluated in the field.

Jan 1, 1985

The purpose of this study was to examine the problems of underground coal mining in the United States, and to develop recommendations for an integrated Research and Development Program aimed at resolving these problems. Specific objectives of the study were as follows: ? To identify the existing inadequacies that have adverse effect on Health, Safety, External Environment, and Productivity. ? To identify opportunities for technological advance s to correct these inadequacies. ? To develop an integrated Research and Development Program designed to accomplish the advances identified. Many of the recommended tasks are dearly long range; this is especially true of those for study of future mining systems. However, funding recommendations in this Report are presented for a 5 -year period, since the developments accomplished during this period will undoubtedly be a factor in the formulation of the follow on tasks. Where applicable, the recommended Research and :Development could include development and test of pilot model equipment.

Jan 1, 1970

This manual covers the operation and lubrication procedures for the Eimco Pumpable Roof Bolting Machine. This machine meets U. S. Bureau of Mines Schedule 2G Approval. This manual is divided into three major parts: 1. Machine dimensions; 2. operating instructions and; 3. Lubrication. Whenever front or rear, right or left arc mentioned it is assumed that the reader is standing behind the machine looking toward the boom. The boom is at the front of the machine. Safety When leaving machine parked on an incline turn wheels into the rib or block wheels. Do not run over power cables. Make sure your power cable is up out of the way so others can't run over it. Machine has a fire suppressor system for the power unit. The remote actuator (pressure cylinder) is located at the operator's station. Components and service procedures on page 59.

Jan 1, 1976

By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to can and ore rate mines in various foreign countries. This interpretation of the mining laws of the Irish Free State has been prepared from the best available material in Washington and is released subject to amplification and correction, if necessary, by American foreign-service officials. INTRODUCTION This paper is based upon the mines and minerals act, 1931, enacted by the Legislature (Oireachtas) of the Irish Free State (Saorstát Eireann), December 22, 1931, the lull title of which is "An act to establish a board to perform functions in relation to mines and minerals, to authorize the making of lenses of mines and minerals belonging to or vested in Saorstát Eireann, to name provider for facilitating the working of other mines and minerals and, for imposing restrictions on the working of minerals required for the support of buildings and works, to amend the law with respect to mines, and for other purposes incidental to the matters aforesaid.'

Jan 1, 1933

By O. C. Blade

Diesel fuel is being used in greater volume than ever before in the United States. During 1950 railroads used 43 percent of the total volume of Diesel fuel sold, smelters, mines, and manufacturing plants used about 13 percent, highway vehicles such as trucks and busses, and equipment such as tractors and bulldozers accounted for approximately 20 percent, about 12 percent was used by water craft, and the remaining 12 percent by gas and electric utilities, the military forces, and oil companies. These figures were calculated from data issued by the Bureau of Mines. 2/ Comparable figures for 1951 and for 1952 to date are not available, but recent information indicates that well over 11,000,000 barrels of Diesel fuel per month are produced by the country's refineries. 3/ More information on this increasingly important type of engine fuel is needed by the petroleum industry, engine manufacturers, and consumers, particularly on the grades and qualities of the Diesel fuels being marketed. To supply this information the American Petroleum Institute and the Bureau of Mines, United States Department of the Interior, under cooperative agreement, are conducting annual surveys of Diesel fuel oil produced in refineries in this country.

Jan 1, 1952

By Lloyd A. Morley

This eight-chapter document is the second volume of a two-volume report that presents a comprehensive outline of coal-mine electrical power systems from theory to practice. Together, the two volumes contain the vital aspects that go into planning and designing a mine power system. Building upon Volume I, the subject of protective equipment and relaying starts Volume II, first as an introduction in Chapter 8, then by a treatment of device selection in Chapter 9. Chapter 10 continues system protection in terms of transients and overvoltages. Chapter 11 describes the design of major power equipment, including power centers, switchhouses, and substations. Solid-state applications in mining are given in Chapter 12, and batteries and battery charging are discussed in Chapter 13. Chapter 14 covers electrical-equipment in hazardous locations of mining operations. The report concludes with Chapter 15, a discussion of electrical maintenance as well as some specific mine electrical problems. Information on surface and underground use is included in all these chapters. An index finishes the documentation and is cross-referenced to both report volumes.

Jan 1, 1982

By G. L. Oldright

As a rule, the usual zinc retort smelter fired with natural gas made its own burners, of which there might be 300 per block, out of standard pipe fit-tings. The gas was discharged through a feeder pipe at various distances into a cylindrical horizontal "blow hole" through a pillar block and thence into the furnace; the best location of this gas-feeder pipe was at the horizontal central axis of the blow hole; the side entry into the blow hole usually was used. The air entered the same blow hole behind the gas, through a short nipple, in the inner end of which was a constructing orifice in a clay plug; in this ,work cone-shaped funnels of various lengths also were used. Even with the air and gas correctly proportioned to each burner, small differences in their dimensions were found to influence greatly the temperatures reached, their uniformity, and consequently the percentage of zinc extracted. This fourth paper of a series on cooperative work in the zinc retort plants of the Eagle-Picher Mining & Smelting Company discloses the methods and principles followed in approximating closely the optimum dimensions for various burners, with examples from experimental and commercial furnaces showing the interrelation of such dimensions with combustion and temperatures in the furnace.

Jan 1, 1948

The Thermo-MIE personal DataRAM dust monitor (pDR) is a light-scattering instrument approved for use in gassy underground mines by the U.S. Mine Safety and Health Administration (MSHA). However, the use of light-scattering monitors has been inhibited by concerns about inaccurate readings resulting from changes in dust size distribution and composition, as well as concerns about the impact of moisture in the mine air. Because of this concern, the National Institute for Occupational Safety and Health (NIOSH) evaluated the pDR using available data from laboratory tests and mine surveys. The data show that accuracy can vary widely from test to test and mine to mine. In most cases, the results can be improved by using a companion gravimetric measurement to adjust the pDR data.

Jan 1, 2006

By C. H. Bloomster

This study estimated (1) radon and radon daughter emissions from underground uranium mines; (2) the reduction in radon that would be released to the surface by using control techniques such as bulkheads, sealants, backfilling, and positive pressure ventilation; (3) the cost for radon and radon daughter removal from total exhaust air; and (4) total radon and radon daughter discharge for lower occupational exposure limits. For 13 large underground uranium mines, estimated yearly radon emissions from each mine ranged from 900 to 3,400 Ci. The estimated age of air emitted from the mines ranged from 11 to 37 min. Potential radon removal methods for the total mine exhaust were evaluated. The cost of these methods was prohibitive. Diurnal and seasonal changes may affect radon emission over short periods of time, but do not affect the total emissions over the long run. Radon and radon daughter emissions would be little changed by increased ventilation requirements needed to achieve lower occupational exposure limits. The concentrations in the exhaust would be lower, but the total release would be the same

Jan 1, 1984

By R. W. Hiteshue, C. O. Hawk, H. H. Ginsberg, M. D. Schlesinger

The Bureau of Mines studied single - step catalytic vapor - phase hydrogenation of oils derived from coal and oil shale . Treatment of middle oil , from hydrogenation of bituminous coal , gave good yields of gasoline with a German - made molybdenum- zinc - chromium catalyst . The Bureau also achieved good results with duplicates of this catalyst made from domestic raw materials . In one set of experiments with the German catalyst , 38 to 52 wt pct of feed was converted to gasoline . The total liquid product was 91 to 98 wt pct of the feed . Not all this gasoline can be claimed as production , however , because about 20 pct of the feed was in the gasoline range , and part of it undoubtedly survived the hydrocracking treatment . Hydrogenation of crude shale oil in the presence of cobalt molybdate catalyst produced a total liquid product of 89 wt pct of feed . The hydrogenation converted 27 wt pct of feed to gasoline and 44 wt pct of feed to diesel fuel . The remaining liquid product , 18 wt pct of feed , was residue boiling above diesel fuel . The gasoline was of poor quality , with an octane number of 39.1 . The overall product seemed a suitable feed stock for a conventional refining operation . Coker distillate hydrogenation , using a cobalt molybdate catalyst , gave a total liquid product of 97 vol pct of feed ; of this product 60 vol pct was jet fuel and 40 vol pct was diesel fuel . High nitrogen and sulfur in all three of these raw materials severely poison the usual refining catalysts . Thus , the common objective in these

Jan 1, 1964

By Sarkis G. Ampian

Published optical microscopic and X- ray diffraction characteristics of the following compounds are critically evaluated and compared with Bureau of Mines data : Tricalcium aluminate , calcium monoa luminate , dodecacalcium heptaluminate , dicalcium silicate , tricalcium silicate , and sodium aluminate . A recommended set of definitive optical and X- ray diffraction characteristics is presented . These values are used to identify products of the lime soda sinter process for production of alumina . Polymorphism of gamma- , beta- , and alpha prime - dicalcium silicate is reexamined , and new data are presented on polymorphism of tricalcium silicate and sodium aluminate by high- temperature X- ray diffractometry . Polymorphism is not observed for tricalcium aluminate , calcium monoaluminate , and dodecacalcium heptaluminate . Bureau of Mines data indicating a stoichiometry of 12Ca0.7A10 for the phase 5Ca0.3A1 0₂ are discussed . A critical review of the literature concerning calcium dia luminate and sodium undecaluminate ( 8 -A10 ) is also included .

Jan 1, 1964

Many of the difficulties faced by the U.S. mineral industry in 1982 and 1983 emanated from the worldwide recession, from the high value of the U.S. exchange rate, and, in part, from actions taken by foreign governments to protect selected industries. While some problems will be minimized with continued worldwide economic recovery, others remain and may require special attention by U.S. policymakers. These problems include declining U.S. production capacity in selected mining and mineral processing industries, the impact of the high value of the U.S. exchange rate, and protectionist trade practices by competitor nations. Illustrative of the last is the International Trade Commission (ITC) determination in June 1984 that both the domestic steel and copper industries have been substantially injured by foreign imports. In its July 1984 recommendations to the President, the ITC suggested higher tariffs and quotas for 5 years on 70 percent of steel imports but conditioned the aid on cost-cutting and modernization steps by the domestic industry. In the copper decision, two commissioners recommended increased duties, two recommended that quotas be imposed, and one recommended that no relief be provided. The President decided in September to seek voluntary restraint agreements with nations that export steel to the United States and rejected both quotas and higher tariffs on copper imports. General Economic Setting This decade opened with the U.S. mineral industries struggling to deal with double-digit inflation, record high peacetime interest rates, and almost 7 years of oil-cartel-induced energy price increases that seriously affected the profitability of energy-intensive industries such as mineral production and processing.

Jan 1, 1985

By Joseph D. Davis

The term "fusain" was first adopted from the French by the American geologist J. J. Stevenson in 1911, according to Wheeler, (1),3 who applies it to that portion of coal resembling charcoal, which he treats as one of the four ingredients of banded bituminous coal. The term has since been adopted by American writers. The Germans use it with slightly different spelling - namely, fusit. It is the equivalent of "mother-of-coal" and "mineral charcoal" of the earlier British writers. The English word fusain is also applied to "a crayon of fine charcoal" and is derived from the Latin root fusus. OCCURRENCE OF FUSAIN IN COAL AND ITS RECOGNITION Fusain is fairly widely distributed in coals of all ranks in varying amounts. It is almost always present in very thin sheets between the bedding planes of the banded coal constituents and presents a jet-black silky appearance who n the coal is split away. As fusain has little cohesive power the coal splits readily along the planes where it occurs. Such fusain bands often attain appreciable thickness -- frequently 1/4 to 3/4 inch. -Beet (2) has reported a maximum thickness of 2 inches for fusain partings, and Sinnatt (3) has found it in the form of plates and lumps; one lump taken by him from the Peacock mine weighed 3-3/4 pounds. Bore (4) has found it in coal balls. Sinnatt (3) states that fusain occurs in two forms, "the first a hard compact variety occurring rather rarely, which can not be pulverized by pressure of the fingers the second type is the common substance" -- that is, a very friable, easily pulverized material. The writer has also found the two types of fusain in the same coal bed and has observed that the hard variety contained considerable calcium carbonate, which probably entered the material in situ by infiltration. Sinnatt further remarks that the layers of fusain (soft type) usually contain less moisture than the coal (or lose it more readily on exposure), and when exposed they quickly change to flocculent powder so that the fines of the coal as mined are likely to contain a major proportion of this substance.

Jan 1, 1929

By James E. Norman

[The flotation of mica is mentioned frequently in the literature, but must of the references have dealt with the recovery of mica by the old anionic collectors. The first use of the new cationic reagents indicated their superiority- as collectors in the flotation and a. agglomerate tabling of micas, feldspars, quartz, clay, and other acidic mineral, but the separation n of these minerals from each other necessitated study of the flotation of each mineral.]

Jan 1, 1941

By James E. Norman

[The flotation of mica is mentioned frequently in the literature, but most of the references have dealt with the recovery of mica by the old anionic collectors. The first use of the new cationic reagents indicated their superiority as collectors in the flotation and agglomerate tabling of micas, feldspars, guartz, clay, and other acidic minerals, but the separation of these minerals from each other necessitated of the study of the flotation of each mineral.]

Jan 1, 1941

By A. Gene Collins

The Bureau of Mines undertook research to determine the bromide and iodide content of Mississippi and Alabama oilfield waters of the Tertiary and Cretaceous Period to determine genetic relationships of the ions, to determine their origin, and to determine their genetic relation to petroleum. The 280 samples were analyzed after a pretreatment to remove interferences. The iodide was oxidized to iodate and was titrated with thiosulfate. The bromide was oxidized to bromate and was determined iodometrically. A computer was used to calculate the correlation coefficients of iodide to bromide and to other ions. The other ions are sodium plus potassium, calcium, magnesium, chloride, bicarbonate, and sulfate. The mineral content of the samples ranged from 52 to 1,760 mg/l for bromide and from 2 to 65 mg/l for iodide. The mean bromide-to-chloride and iodide-to-chloride ratios were 0.0065 and 0.0002. The correlation coefficient matrix and linear plots indicated a definite bromide-to-calcium relationship for the brines investigated.

Jan 1, 1967

By Edward L. McHugh, Stanley M. Miller, Jeffrey K. Whyatt

The point estimation method can be applied to the safety factor (SF) equation for any specified rock slope failure mode (such as plane shear, step path, or wedge) to obtain reliable estimates of the mean and standard deviation of the SF probability distribution. A gamma probability density function is recommended for modeling this probability distribution, because it allows only for positive values and is flexible enough to provide symmetrical shapes and right-skewed, exponential-type shapes for the SF distribution. The mean and standard deviation define this distribution, which then can be integrated numerically from 0 to 1 to obtain the probability of sliding, PS (portion of the SF distribution where SF < 1.0). The overall probability of failure, PF, for the potential slope failure mass is the joint probability that the rock discontinuities are long enough to allow kinematic failure (PL) and that sliding occurs along the rock discontinuities (PS); that is, PF = PSPL. This method for estimating the probability of sliding is extremely efficient computationally, and thus, expedites slope stability simulation routines used by NIOSH software to stochastically describe rock slope behavior and assist the engineer in designing catch benches for large rock slopes. Enhanced bench design translates into increased operational efficiency and safer working conditions in open pit mines and quarries.

By Ren G. Dong, Richard McCormick, Dan E. Welcome

Vibration exposure at workplaces is generally multi-axial. The health effects of vibration exposure also likely depend on the vibration direction. Therefore, there is a wide interest in the simulation of multi-axial vibration in laboratory experiments. Advances in technology have led to the development of a new 3-D test system for studying hand-transmitted vibration exposure and health effects. The purposes of this paper are to introduce the system and to present the results of its preliminary evaluations. Test System As shown in Figure 1, the system is basically composed of three vibration generators, a multi-axis vibration control system, instrumented handle, handle fixture, and shaker-fixture linkages (stingers). [ ] Figure 2 shows the array of three vibration generators (MB Dynamics, Energizer BLACK-500 lbs) and their associated support bases and foundation developed by MB Dynamics (Cleveland, USA), which create the 3-axis simultaneous motion. These electrodynamic exciters are powered by power amplifiers which provide current proportional to the analog drive signal from a controller. The controller (JAGUAR Multi-Input/Multi-Output closed-loop vibration controller) was provided by Spectral Dynamics, San Jose, California, USA). NIOSH-designed instrumented handle was equipped on the system.

Jan 6, 2006

By W. J. Kroll

Despite the fact that barium minerals are plentiful and widely distributed in nature, this element is one that we do not yet know how to prepare cheaply in metallic form. This is due to its chemical activity, as evidenced by its great affinity for fluorine, chlorine, oxygen, nitrogen, hydrogen, and sulfur. Furthermore, it forms a very stable subchloride and subfluoride, which prevents isolation of the metal by fusion electrolysis from a halide bath. A good survey of the metallurgy of barium calcium, arid strontium has been made recently in Light Metals (54,55).3/ Metallic magnesium (46), calcium (83), barium, and strontium (27) reduce each other&apos;s oxides. Proof of this can be found in the activation of BaO after reduction with Mg, which leads to the formation of so-called "Maquenne" mixtures (58) used for absorbing gases. However, it is impossible to extract the reduced metal- from the residue, a fact that Guntz (25) attributed to the formation of barium suboxide. There is no necessity for presuming the formation of such a compound, as it has boon established that in the reduction there is always formed an alloy of the alkaline-earth metal with the magnesium, which is capable of producing hydrogen when brought into contact with water. The reduction of alkaline earth-metal oxides with aluminum was observed by Mallet (57) in 1877, but recent investigations have shown that the end product of the reaction is an alloy of aluminum with the alkaline earth metal (1,2). Silicon also has been suggested as a reducing agent, and the results obtained are the same (84,85).

Jan 1, 1945

By Jeffrey P. Schubert

The study site in northeastern Illinois underwent surface mining for coal in 1943 and was reclaimed by the state of Illinois in 1972-1973. Additional soil amendments and seed were applied to the spoil surface in 1975-1980. Previous studies in 1975-1978 had shown that the surface spoil materials and five final-cut lakes at the site were quite acidic and the lakes contained high concentrations of sulfate and dissolved metals. Surface runoff water from monitoring plots in 1976 were only moderately acidic and the mean concentrations of most dissolved metals and sulfate in the runoff waters were less than 25% of the concentrations found in Lake B. By 1980, vegetation had become well established over most of the mined area. However, the five final-cut lakes (Lakes A-E) remained acidic. The purpose of the study reported here was to determine the physical and geochemical subsurface conditions of the spoil materials, the hydrologic flow system within the spoils, and the magnitude of acidic spoil leachate migration into the lakes and into the wetland prairie north of the mine site. Lakes A, B, C, and E were still very acidic in 1980-1981 (pH range: 2.9-3.4; aridity range: 110-860 mg/L as CaCO3). Lake B had the worst water quality, with mean concentrations of dissolved aluminum, iron, manganese, and sulfate of 75, 25, 37, and 3340 mg/L, respectively. Shallow groundwaters in spoil materials around Lake B had a lower pH and about two to four times greater concentrations of aridity, aluminum, manganese, zinc, and other metals and nearly 20 times greater dissolved iron than the water in Lake B. The shallow groundwaters in undisturbed soils and bedrock 10-30 m north of the mine site spoils generally were alkaline, but did contain occasional moderately high sulfate and metal concentrations. Pumping tests and recovery tests conducted in piezometers showed hydraulic conductivities of spoil materials ranging from less than 10- to 10-5 m/s; hydraulic conductivities of natural soils and bedrock were measured between 10-10 to 10-7 m/s. Water levels in spoil materials increased rapidly in response to rainstorm events and the recession curves were relatively quick to decline, lasting only two or three days. Quick infiltration of rainfall into the spoil surface and percolation down to the water table caused a rise in groundwater levels and movement of spoil groundwater into the lakes. This groundwater component in the lake water budgets could account for most of the water quality problems occurring in the acid lakes.

Jan 1, 1984