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By A. B. Needham

The Great Eastern nickel deposit is located in the western foothills of the Virgin Mountains in the Copper King or Bunkerville district situated in the southeastern part of Clark County, Nev. It is covered by a group of eight claims that can be reached by turning south from U. S. Highway 91 at Riverside, Nev., and driving about 12.6 miles southeast over a winding mountain road, which rises from about 3,000 feet to 4,000 feet in elevation. The climate is dry, with only a small amount of rainfall throughout the year. The temperature ranges from hot during the summer to short periods of freezing weather during the winter months. The vegetation is of the desert variety, and no timber is available for mining. Water for mining purposes would have to be pumped from lower areas. A granitoid gneiss comprises the largest part of the rock outcrops. It has a steeply dipping foliation that strikes about N. 75° E. The gneiss was intruded by basic dikes, which in turn were intruded by pegmatite dikes. The ore occurs as lenticular bodies formed by the convergence of several pegmatite dikes within the main dike. The principal sulfide minerals are pyrite, pyrrhotite, and chalcopyrite, which contain a small amount of nickel. Late in the year of 1939, the Bureau of Mines undertook an exploration project on the Great Eastern property to extend or delimit the known mineralization. Underground work, consisting of 590 feet of drifting and crosscutting, was completed in September 1940, and 1,091 feet of diamond, drilling for downward extension of an ore body in the Lower edit, which was completed in February 1941.

Jan 1, 1950

By S. E. Khalafalla

The ability of potentiometric, gas-sensing electrodes to reliably monitor free gaseous molecules in solution has been recently demonstrated. A gas such as sulfur dioxide from a dilute sample solution diffuses through a hydrophobic, gas-permeable membrane to an internal filling solution. The latter solution contains a sufficiently large excess of sodium bisulfite, the concentration of which can be considered constant regardless of the quantity of sulfur dioxide entering by diffusion. The electrode response is essentially due to the liberated hydrogen ions from the bisulfite-sulfur dioxide equilibrium. This Bureau of Mines report describes a new technique used to detect the formation, and to estimate the stability constant, of gas-molecule and gas-ion complexes in solution, as part of an effort to minimize the undesirable environmental impacts associated with mining and mineral processing. Although the unknown activity coefficients of the neutral and ionic species in the external solution complicate the quantitation of results, methods to circumvent these difficulties are presented. The technique is based on the isometric shift of the Nernst diagram of ion-selective electrodes to higher concentrations relative to the standard aqueous calibration curve. The method is applied to detect and estimate the formation constant of a sulfitocitrate complex, and agrees well with an independently determined stability constant of the disulfitomercu-rate complex.

Jan 1, 1978

By Robin B. McCulloch

No producing mines are in the study area. Sample results indicate the only resources in the study area are low grade phosphate deposits associated with Cuyama Phosphate Mine (fig. 1). Within the study area, are more than 21.4 million tons of inferred subeconomic phosphate rock resources which would be reserves at an 80 percent higher phosphoric acid price; weighted average grade is 4.84 percent phosphorous pentoxide (P205). About 17.6 million tons of similar grade are outside the area to the northwest. The South Cuyama Oil Field, adjacent to the study area (fig. 1), produces petroleum from the Vaqueros Formation which underlies parts of the study area. Oil and gas potential was evaluated by U.S. Geological Survey. INTRODUCTION Location, Size, and Geographic Setting The U.S. Bureau of Mines conducted a mineral survey of the Fox Mountain RARE II area (No. 5120) during the summer of 1981. The area was examined to determine the presence or absence of mineral resources and reserves, and to estimate tonnage and grade where possible.

Jan 1, 1982

By H. C. Howarth

The preliminary tests referred to in this report wore made at the Bureau's Experimental Mine under the general supervision of G. S. Rice chief mining engineer, to determine whether rock dust way be used to extinguish or control mine fires. DESCRIPTION OF THE DUST USED The dust used for application by hand was made from draw slate taken from the Experimental Mine. This draw slate was crushed in a hammer-type crusher fitted with 1/16 inch by 2-inch slotted screens. A sizing test of the dust showed 96.5 per cent through 20 mesh, 69.4 per cent through 48 mesh, 46.2 per cent through 100 mesh, end 33.5 per cent through 200 mesh.

Jan 1, 1927

By Ellsworth R. Spencer

A lightweight fiberglass feed leg for hand-held pneumatic percussion rock drills has been fabricated and tested by the Bureau of Mines. Its lighter weight facilitates easier handling of the rock drill apparatus, thereby reducing the potential for back injury to the driller and in- creasing drilling productivity. Current hand-held feed leg drills of the same class are 50 pct heavier than the Bureau-devised feed leg drill, which is comprised of a reduced-noise drill and the fiberglass feed leg. In-mine tests of the fiberglass leg showed that its performance and cost are comparable to those of standard aluminum feed legs.

Jan 1, 1985

By R. Carson Dalzell

The use of nuclear fission for chemical process heat offers the special advantage of high temperature, limited only by materials of construction. The process heat may be supplied economically at elevated pressures, since no compression of combustion air is required. For the initial effort in developing a high-temperature reactor, the indirect cycle, using helium as the heat-transfer medium, was chosen. The major problems are the design of high-temperature fuel elements, construction of an exchanger to transfer heat to process streams in the range of 2,500° F., and development of compressors capable of recycling helium at 1,000° F. and above. A conceptual design of a nuclear reactor to furnish process heat for coal gasification has been made. Spherical fuel elements utilizing a graphite structure, impregnated with uranium carbide fuel, were chosen, as spheres offer the possibility of easier loading and unloading of the reactor. Calculations of pressure drop and gas-pumping power for the system are included.

Jan 1, 1959

By A. C. Fielder

It is with some diffidence that I venture to address the Montreal Section of the Society of Chemical industry on the subject of motor fuel from coal at a time when crude petroleum is produced in greater quantities than at any time in history, and at a time when the known reserves exceed all expectations, even the optimistic estimates of the Committee of Eleven of the American Petroleum Institute. Not only are new fields being discovered in America a -an embarrassing frequency but sources outside of the North American Continent show, unmistakable signs of adding materially to the world's sources of oil. Were it not for the tremendous scientific and technical importance of the work done in the past few years in transforming coal into liquid motor fuels, I should prefer to let this subject rest until a more propitious time, such as prevailed some years ago, when the gasoline consumption curve was rising rapidly and the production curve was slowing in its upward rise. That was the period which stimulated the researches which resulted in tetra ethyl lead and anti-knock gasolines on this side of the Atlantic and in methanol, synthetic gasoline and hydrogenation of coal on the other side. Some of you will recall a symposium on Motor Fuels and Oil Conservation held at the Chemists' Club n New York in September; 1925. Dr. R. L. Brown and I presented a paper at this meeting on "Complete Utilization of Coal and Motor, Fuel, in which we pointed out that coal was the most likely raw material source of gasoline substitutes if and when needed. We grouped the present and future, processes' for obtaining motor fuel from coal in three classes, namely:

Jan 1, 1928

By W. A. McKinney

A sample of oxidized copper ore from a large deposit located in Pinal County, Ariz., about 50 miles northeast of Tucson, was treated by the Federal Bureau of Mines in a small-scale continuous pilot plant by a procedure which comprised acid curing complemented by water leaching and countercurrent decantation washing in a series of drag classifiers. A feed was prepared by pugging minus 1/4-in, ore with concentrated sulfuric acid and about 10 pct, of eater, followed by curing in batches for about 24 hr. The cured ore was fed continuously to a leach drum, where it was mixed with advance solution from the countercurrent washing system to dissolve the sulfated copper. The pulp was thickened and washed in four Esperanza-type classifiers, using a flocculating agent to obtain rapid settling and thickening. The leached ore pulps thickened satisfactorily in the drag classifiers when about 0.8 lb. of a polyacrylamide flocculant per ton of dry feed was used. Clear overflow liquors were obtained, and classifier rake products containing about 60 pct. solids were produced, As much as 90 lb./hr. of ore was treated in the plant, with a recovery of 60 pct. of the total copper or 80 pct, of the acid-soluble copper when 2 tons of water per ton of feed was used in washing. The acid consumption was 4.3 lb./lb. of copper recovered. On the basis of the maximum feed rate employed and the effective pulp-settling area of the classifiers, a total of 1 sq. ft. of pool area was required per ton of dry feed per day for the thickening and washing operations. The washing efficiency in the test was 95 pct.

Jan 1, 1960

By E. J. Matson

From February until July 1943 the Bureau of Mines conducted an exploration project at the Majuba Hill mine to determine tonnage aria grade of the copper and tin ore and to search for extension of the mineralization. The work comprised sampling, long-hole drilling, underground excavation, and ore-dressing test.

Jan 1, 1948

By A. D. Hahn

This report describes reconnaissance by the Bureau of Mines of titanium-bearing beach sands on Ship Island in the Gulf of Mexico off the south coast of Harrison County, Miss. The purpose was to determine the ilmenite, rutile, and associated heavy-mineral content of black-sand-bearing beach sands. The investigation was part of a survey of titanium resources of the United States. Ilmenite (FeTi03), an iron-titanium oxide, is the major titanium-bearing mineral consumed in the titanium pigment industry. Rutile (TiO2), titanium dioxide, is used mainly as a constituent in welding-rod coatings and in producing titanium metal. The major fieldwork was conducted during the first half of February 1961. Nine holes, totaling 220 feet of bore, from which 110 samples Her taken, were drilled at widely spaced intervals on the island.

Jan 1, 1962

By Ronald A. Vary

This paper is one of a series prepared by the United States Bureau of Mines dealing with milling methods and costs. In view of the current revival of interest in gold mining, information dealing with practices and costs in the development of gold properties is apropos. Milling practice at a small gold property in the prospect stage is described where, with a small outlay for plant and equipment, development has been carried on for about 20 months on the proceeds of the mill operation with little additional expenditure. The paper shows about what may be expected as to costs at a small property operated under northern climatic conditions and with rigid economy throughout the plant.

Jan 1, 1931

By K. E. Stanfield

The Bureau of Mines oil-shale program, initiated in April 1944, is concerned with the future utilization of oil shale in the United States as a source of liquid fuel. One phase of this program is the accumulation of information on the location, extent, and richness of oil-shale deposits that may be suitable for processing to oil and related products. A previous publication5/ presented, by means of logs, the oil yields of sections of the largest known oil-shale deposit in this country -the shales of the Green River formation occurring in adjoining portions of the states of Colorado, Utah, and Wyoming. This present supplementary report presents the oil yields of cores from 48 holes drilled during 1952 to 1954 in the Green River formation of Colorado, which is distributed over an area of more than 1,000 square miles. The oil yields of the 48 oil-shale sections, involving the assay of 9,651 samples, representing 22,451 feet of core, are presented by means of logs. In addition, the oil yields of samples comprising the maximum sections of 15 gallon-per-ton shale are tabulated for these cores and for the 28 cores from Colorado which were logged in the previous report.

Jan 1, 1957

By Lisa Steiner, Robin Burgess-Limerick

In 2004, underground coal mines in the United States reported 3,405 injuries to the U.S. Mine Safety and Health Administration (MSHA). Of these, 17 percent were associated with the use of bolting machines, 8 percent with continuous miners, and 4 percent each with scoop/load-haul-dump (LHD), shuttle cars and personnel transport. Analysis of the injury narratives identified five hazards that required attention. They are rock falling from supported roof inadvertent or incorrect operation of bolting machine controls, handling continuous miner cable, collisions while driving underground vehicles and driving or traveling in underground vehicles on rough roadways. The rate of lost-time injuries has steadily decreased during the past 10 years (from more than 10 per 100 FTE in 1995, to six in 2004). However, underground coal mining remains a hazardous industry. One of the contributors to this elevated injury risk is working with or near underground coal mining equipment. Roof bolting machines and continuous miners have been consistently identified as high risk equipment. They account for approximately 24 percent of all injuries to underground coal miners (Sanders and Shaw, 1989). LHD's, shuttle cars and personnel transports are also associated with injuries in underground coal mines (Burgess-Limerick, 2005). Conventional analyses of injury statistics typically provide tables detailing the breakdown of injuries by body part nature of injury or mechanism of injury. Such analyses are worthwhile and may be helpful in tracking broad trends over time. Further information is available in the narrative text field completed for each injury reported. The detail contained in these narratives varies. However, they generally provide some insight into the causes of the injury, such as the activity being performed at the tune of

By Robert Lundquist

REAM is a unique method of rock breaking using high energy projectile impact. This report-describes the most recent in a series of tests demonstrating mining applications for the REAM method. In an underground limestone mine at Greer, West Virginia, REAM was used to drive a short tunnel and drill a large diameter borehole. Along with breakage data from these tests the goal of the program was to examine environmental problems which might result from the use of cannons under-ground. A total of 103 shots was used to advance a 14-l/2-feet high by 10-feet-wide face a distance of 5-1/2 feet. It is estimated that the 9.3-pound-concrete projectiles launched at 5000 feet per second will break an average of 0.78 tons of limestone or 67 percent of the 1.125 tons of granodiorite broken in previous tests. The 9-inch-diameter borehole was drilled horizontally by repeated axial impact for 7 feet, 2-1/2 inches by 21 shots giving an average of 4.12 inches per shot. Scaling this result to compressible impact energy yields an estimated 5.8 inches per shot for a 12.8-inch-diameter hole compared to 8 inches per ~hot for a 16-inch-diameter hole in granodiorite. Noise measurements indicate that a silenced cannon can be used within a few hundred feet of mine personnel in a room and pillar mine within the legal limit of 140 dB impulse without additional protection. Some fume measurements were made with satisfactory results, even though the military propellants used produce much greater quantities of toxic fumes than the liquid propellant proposed for the future.

Jan 1, 1976

By John A. Johnson

Tests ere conducted at the Mount Weather testing adit of the 57 Bureau of Mines on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. Equipment Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is mace of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.

Jan 1, 1939

By John A. Johnson

[Tests were conducted at the Mount Weather testing adit of the Bureau of Mines4/ on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. EQUIPMENT Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is made of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.]

Jan 1, 1939

By R. M. Santmeyers

This paper presents one of a series of digests of foreign mining legislation and curt decisions that is being prepared in advance of a. general report relative to the rights of American citizens to explore for minerals and own and operate mines in various foreign countries. This interpretation of the mining legislation of Madagascar was prepared from the best information (in French) available in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers, to whom it dill be referred through the courtesy of the Department of State. INTRODUCTION The basic mining law of Madagascar is the decree of 1923, signed at Rambouillet by the President of France on July 19, and published in the Journal Official de Madagascar et Dependances. It has been modified by a number of subsequent laves and regulations, generally of minor importance.

Jan 1, 1933

By L. M. Chan, D. H. Carlson, J. B. Johnson

"Abstract — Concentrations of tailpipe pollutants from diesel-powered. underground mine vehicles change over time due to engine wear and the need for maintenance. Since this deterioration in pollutant emissions may adversely affect the air quality in an underground mine, it should be monitored and controlled. This paper presents decision criteria concerning when to service a mine vehicle diesel engine. These criteria, based on mine air and tailpipe concentration measurements, are designed to maintain the tailpipe concentrations within limits that assure satisfactory mine air quality.Application of the deterioration criteria to mine vehicle emissions involves:establishing, for each pollutant, the allowable deterioration factor, anddetermining the deterioration factor, from the mine air and tailpipe diesel pollutant measurements, and the mine air threshold limit values (TLVs).If the deterioration factor is greater than or equal to the allowable deterioration factor the vehicle is removed from service for maintenance.An analysis applying the criteria to measurements made in an underground coal mine is presented. The tailpipe pollutant concentration data were collected using the Emissions Mea-surement Apparatus (EMA) developed by Michigan Techno-logical University. Since the TLV for diesel particulate matter (DPM) has not yet been established assumed mine air DPMTLVs of 15 and 1.0 mg/m3 were used in the analysis. For all of the diesel haulage vehicles included in the analysis. DPM was found to be the critical pollutant (the one most in need of control). For an assumed mine air DPM TLV of 15 mg/m3 none of the diesel haulage vehicles would he removed from service. However reducing the DPM TLV to 1.0 mg/m3 would make it necessary to remove two of the three vehicles tested from service."

Mar 1, 1992

By E. A. Johnson

As part of its effort to reduce the environmental impact associated with mining and metallurgical operations, the Bureau of Mines used a modified form of the Environmental Protection Agency's Extraction Procedure toxicity test on copper reverberatory slags that contained low, medium, and high levels of the impurity elements As, Pb, Sb, Bi, and Zn. All tests resulted in extracts that did not exceed those limits published in the May 19, 1980, Federal Register; there-fore, these solid wastes were designated as nonhazardous for most landfill disposal situations. However, arsenic and lead levels disturbingly close to the allowable limits--and even higher levels of copper and zinc, for which there are no established limits--leached from the high-impurity-element granulated slags. These slags should be handled in such a way so as to minimize the possibility of water contamination. One baghouse dust was tested according to the EPA procedure and found to exceed the extract limits by a factor of 10. This solid waste may be considered hazardous.

Jan 1, 1982

By W. A. Haley

This is the second of a series of publications that describes the progress of mechanical longwall coal mining in the United States in which a German coal planer was employed.3/ Details of the equipment, a description of its operation, and the results obtained in mining the experimental panel were published in the preceding report. Experimental mining with the planer in the first panel showed an improvement in performance over conventional mining methods at the coal company's Stotesbury 11 mine. The work, which was begun on an experimental basis, soon proved successful, and the coal company purchased the equipment for continued use. Two panels, adjacent to the first, were developed and mined with the planer. Each of these panels was shorter than the preceding one because water seepage from a surface creek limited development. On completion of mining in the third panel, the planer equipment was moved by the cooperating company to a nearby mine operated in the same coal bed where a large area of coal suitable for planer mining is available.

Jan 1, 1954