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By K. L. Paciorek

The primary objective of this final phase of Contract No. H0133004 was to provide a description of all experimental assemblies and procedures used throughout this project in such a detail as to permit duplication of the tests in any other laboratory. A further objective was to summarize and evaluate all results generated throughout the duration of this program and to tabulate all the materials and data in such a manner as to allow this report to be used as a reference index for specific compositions or groups of compositions regarding potential hazards arising from their use .in underground coal mining operations. The report also contains an updated survey of the literature on thermal oxidative degradation of compositions investigated under this contract.

Jan 1, 1978

By J. B. F. Champlin

The continuing development of the nuclear industry in the United States requires a program of waste disposal that insures against the release of large amounts of radioactivity to the environment. This paper describes research on one proposed means of disposal of this waste, that of injection into geologic formations at depth. Nuclear production plant wastes were simulated and injected into samples of sedimentary rock obtained from outcrops, quarries, and deep wells. Changes in the chemical and physical characteristics of the rocks caused by the interaction of ions and suspended particles in the waste solutions with the cementing material and claylike particles in the rock are discussed. Laboratory tests show that nuclear wastes can be injected into many natural porous, permeable geologic formations. Injectivity can be maintained over a longer period by monitoring the ionic balance and particle-size distribution of waste streams. The combination of permeability and porosity with low cation-retention capacity, as exhibited by most sandstones, would satisfy the engineering requirements for the subsurface disposal of nuclear waste. Shales and clays with their low permeability and high cation-retention capacity would make excellent confining formations. The amount of cation retained by sedimentary rocks increases with increasing valence or concentration of the cation or decreasing brine concentration. The use of rock cores as model reservoirs had proved successful in determining some of the parameters that need to be considered in full-scale field disposal of wastes.

Jan 1, 1967

By W. S. Sanner

This report describes the commercial application of the launder screen in anthracite-industry fine-coal cleaning operations. No new device, the launder screen has been used since the early part of the present century to size, screen, classify, and deslime the fine-anthracite sizes (Buckwheat Nos. 1 through 5) recovered by "river-coal" men dredging along streams draining the anthracite fields. The launder screen is stationary, has no moving parts, requires ample water for operation, and can be constructed economically on the job. Essentially, it consists of a wooden trough with baffles placed through its width to form a well system. The wells are covered by fine-mesh woven-wire screening. Each well is tapped with a number of orifices, and the hydraulic suction head developed in this manner removes high-gravity fines and slimes through the screening as underflow to waste. Material retained on the screen surface discharges as overflow product.

Jan 1, 1954

By J. E. Shelton

This presentation covers the results of laboratory studies conducted by the Bureau of Mines Mineral Dressing Section, Northwest Electrodevelopment Laboratory, Albany, Oreg., on alluvial sands from Dismal Swamp, Bear Valley, and Cascade, Idaho. The search for radioactive minerals has led to the reexamination of alluvial deposits; in the process of this reappraisal the frequent presence of minerals bearing columbium and/or tantalum was toted. Because of increased demand for these metals by the defense industries and because these industries depend upon foreign sources for their supply the domestic alluvial black sands are being considered, as a possible domestic source. However, utilization of these alluvial deposits depends upon development of methods of concentrating these valuable minerals. The primary objective of the test work was the study of the effect of attrition scrubbing, sizing, magnetic, electrostatic, and gravity separa¬tion as methods for concentrating and recovering the columbium and tantalum-bearing minerals, samarskite, euxenite, ilmenorutile, and columbite.

Jan 1, 1955

By Kevin Malone

Chrysotile asbestos occurs in many counties in California, and a small production had been reported at times, but development of deposits had been disappointing. A reconnaissance survey by the Bureau of Mines indicated that several deposits in the serpentine belt in Shasta, Trinity, and Siskiyou Counties might contain enough asbestos of filler grade to supply the growing demand on the west coast. Accordingly from 1956 to 1958 parts of the Mount Eddy and Shasta View deposits were investigated by trenching and diamond drilling to determine their potential. The work comprised construction of roads, bulldozer trenching, excavation of areas for diamond drilling, sampling, and upping. The trenches were excavated to expose the surface extent of some of the asbestos-bearing areas, To determine the downward continuation of asbestos-bearing sections and to secure samples for test purposes, six diamond drill holes, totaling 1,738 linear feet, were drilled in two selected areas. The trenching and core-drilling indicated that the asbestos-bearing material occurs as ribs and lenses of varying thicknesses in a broad belt of serpentine, about 600 feet wide and several miles long,

Jan 1, 1962

By F. W. Wessel

Manganiferous carbonate slates of the Cuyuna range, which are part of the unoxidized thin-budded iron formation, represent a large potential source of manganese. This report details recent bench-scale research by the Federal Bureau of Mines in applying mineral-dressing techniques to these materials in order to investigate their potential uses. Work outlined in the report was directed toward the production of concentrates usable as iron-blast furnace feed, but an equally important objective might have been to furnish an enriched feed for extractive processes for recovering manganese. Flotation concentrates were prepared that contained 11.1 percent manganese, 27.8 percent iron, and 12.2 percent silica, with recoveries of 73 percent of the manganese and 48 percent of the iron. Calculated analysis for a simulated sinter suggests a product containing 16.0 percent manganese, 40.2 percent iron, and 17.6 percent silica, with 31 percent recovery of the dry weight of the ore. The silica in the flotation concentrates was due to quartz and iron silicates. Substantial quantities of the iron silicates (stilpnomelane and smaller amounts of minnesotaite) were present in the slate, and the need to reject these minerals limited the recovery of iron. The sintered flotation concentrate would be usable as ferruginous manganese ore for iron blast-furnace feed because of its favorable manganese silica ratio. The unsintered flotation concentrates, representing 45 percent of the feed weight and containing manganese enriched in the ratio of 1.6 : 1, also could be used as feed to processes for extracting manganese.

Jan 1, 1961

By C. W. Owings

"Ventilation is one of the most important features of coal mining, and if a mine is exceptionally gassy it is often difficult to ventilate it in such a way as to make it safe. The general system of splitting the main air current so that two, three, or more sets of room entries are ventilated by the same current of air does not provide a safe method if non-permissible electrical equipment, such as cable-reel, crab-reel, or trolley locomotives are used on gathering haulage, or if open-type hoist or pump motors are used. The problem has been greatly simplified at the Crucible mine of the Crucible Fuel Co. at Crucible, Pennsylvania.The system is not only applicable to the room-and-pillar method of mining, but it may be adopted for any panel system of mining. There also appears to be a definite application in mechanized mining, where the rapid extraction often results in inadequate attention to ventilation and where the gassiness of the section generally increases because, as compared to hand loading, the methane has less time to drain off. The system to be described should commend itself to coal-mining men.ACKNOWLEDGMENTSThis investigation was made possible through the courtesy of H. J. Nelms, general superintendent. E. M. Marshall, safety inspector, E. G. Sauers, assistant superintendent, and Thomas Mark, mine foreman, assisted in the collection of information."

Sep 1, 1931

By Zsuzsanna Zborovszky

Investigation of the discharge duration power and current relation required for ignition. The current and power amplitude-discharge time curve was found to flatten out over 3 ms. It is concluded that discharges having at least 3 ms power maximum are required for reliable testing of the ignition limit for resistive circuits. Investigation of the effect of molten cathode on the discharge duration and igniting ability of the discharge. The surface tension of the liquid metal causes a very fast separation and consequently a much shorter discharge duration than the solid electrode would have. The minimum discharge voltage effect overrides the effects of the temperature of electrode, material, or atmosphere. Investigation of the effect of different surface layers on the discharge duration. Oxides and sulfates were found to give significantly longer duration than the "clean" metal itself in most cases. The lowest ignition current was obtained with CdS04 coatings. Ignition was obtained with 0.7A at 30V, which is below the corresponding minimum igniting current obtained from the BASEEFA curve for circuits containing Cd, Zn or Mg.

Jan 1, 1977

By K. E. Tame

An alkaline leaching procedure for recovering uranium from a submarginal 0.1 percent Ug Og calcareous carnotite ore from the Shiprock , N. Mex . , area was investigated . A recovery of 72 percent of the uranium was attained in a preliminary test embodying the commonly accepted practice of ( 1 ) alkaline leaching at 90° C , ( 2 ) multiple stage filtration and washing for recovery of a clear pregnant solution , and ( 3 ) caustic precipitation of uranium as sodium diuranate , with recycle of the barren solution to the leaching and washing circuits . Ion exchange resins were used in a second , less orthodox test that comprised ( 1 ) sodium carbonate leaching of minus 10- mesh ore at 90 ° C to dissolve the uranium , ( 2 ) filtration to recover the leaching reagent for reuse , (3 ) recovery of the uranium- bearing solution in the filter cake as a pregnant slime slurry by repulping of the filter cake followed by a sand- slime separation and countercurrent decantation (CCD ) washing for rejection of the sand fraction , (4 ) recovery of the dissolved uranium from the pregnant slime slurry by resin- in- pulp (RIP ) , ( 5 ) elution of the uranium from the resin with a solution of ammonium chloride acidified with hydrochloric acid , and (6 ) precipitation of the uranium with ammonia gas . About 83 percent of the uranium was extracted from the ore and 95.5 percent of the dissolved uranium recovered by ion exchange . Improved laboratory results were obtained using the RIP process , but larger scale tests would be necessary for economic evaluation of the two processes .

Jan 1, 1964

By Guy A. Johnson

To improve productivity and cut costs, modern underground mining operations have become more mechanized. This mechanization has increased the usage of fuels, hydraulics, and electrical equipment associated with diesel-powered vehicles, thereby also increasing the hazards of underground mine fires. The Bureau of Mines evaluated the fire hazard problem and assembled prototype components for a system that would automatically sense and extinguish fires on mobile underground equipment. The prototype system and alternative designs were in-mine-tested and proved effective. This report summarizes this technology, which can cost effectively help solve the problem of fire hazards on underground vehicles.

Jan 1, 1983

By W. W. Adams

Lower accident rates were the outstanding feature. of the second annual sand and gravel safety competition conducted in 1930 by the United States Bureau of Mines in cooperation with the National Sand and Gravel Association. Both the frequency and, severity rates for accidents were greatly reduced as compared with those shown by the first year's contest, that for 1929. Three times as many plants were enrolled, and the number of man-hours of work represented wad more than doubled. Seventy-six sand-and-gravel plants, situated in 20 States, participated in the competition, as compared with 26 plants, located in 13 States, in the year before. The number of man-hours of employment, which indicated the amount of exposure to occupational hazards, was 4,915,592 an increase of more than 100 per cent over, the previous year's total of 2.259,572 hours. The frequents of accidents declined from 74.4 per million hours for all plants enrolled in the first year's contest to 42.7 per million man-hours for all plants enrolled in 1930. The accident-severity rate was reduced from 9.7 days of disability per thousand man-hours of exposure in 1929 to 5.9 days of disability per thousand man-hours of exposure in 1930.

Jan 1, 1931

By Jr. Hazen

Two statistical techniques, the mean-square-successive-difference test and correlation, are used to investigate the problem of assigning an area of influence to an assay. Data from five hydrothermal deposits, Climax molybdenum, Cebolla Creek titaniferous iron, San Manuel copper, Piedra Hueca copper, and Butte copper, are studied. Two groupings of the assays are used for the mean-square-successive-difference tests. One group involves an increasing sample volume by reaveraging assays to represent a longer sample intervals, the other by regrouping assays to represent longer sample intervals without a change in sample volume.

Jan 1, 1967

By R. E. Heithecker, D. B. Taliaferro

"INTRODUCTION Recovery of core specimens from subsurface formations and their subsequent analysis are important aids in efficient development and operation of oil and gas fields. Gore specimens first were obtained mainly for the geologic information they revealed; now they are analyzed to determine many of the physical characteristics and conditions of the subsurface formations as well. Cores recovered from the producing formations may be analyzed for porosity, permeability, oil content, ""connate"" water content, and other physical and chemical properties of the formation, all to the end of furnishing enough data for making reliable estimates of the quantity and avail¬ability of oil and as within a reservoir and in devising efficient means for their withdrawal.Examination of bottom-hole samples of oil gives valuable information concerning the amount of gas in solution in the oil within the reservoir and the resultant shrinkage of the oil when the gas is released. Producing characteristics of reservoirs nay be determined by means of subsurface pressure and temperature gages and measurements male at the wellhead; however, unless reliable core analyses are available, these data have only limited use in any quantitative study of reserves. In such a study the quantity of oil, gas, and water contained in a unit volume of the reservoir formation is extremely important. Although reliable methods of analyzing cores have been developed and the data thus obtained are valuable, their applications become more limited or reservoirs at higher temperatures and pressures are discovered. This condition results almost entirely from the fact that in recovering a core from a formation of high pressure and temperature by present methods a large part of the fluid content of the core is lost or contaminated to an unknown extent. For a number of years most petroleum engineers have held that if this loss and contamination of the fluid content of a core were eliminated, the value of core analyses would be increased greatly."

Nov 1, 1939

By George T. Krempasky

This report is one of a series of Bureau of Mines Information Circulars dealing with mining methods and costs throughout the United States. It describes drifting, crosscutting, and raising operations at several mines in the Coeur d'Alene mining district, Shoshone County, Idaho. Ore bodies in the Coeur d'Alene district are generally in steeply dipping tabular ore zones, are irregular in shape, erratic in occurrence, and have been extensively mined along the strike and down dip. Because of the extended attitude of the deposits a great deal of development work is required. Drifting, crosscutting, and raising methods are described in this report. Shaft sinking is the subject of another report in the same series.

Jan 1, 1960

By Leslie D. Marrus

This project and final report represent an effort to collect, analyze, and verify reliability and performance data on currently available medium -to-high seam models of continuous miners being used in underground coal mining. The analysis determined availability, mean time and tons between failures, amounts of down time associated with various failures, labor and part costs required to correct failures, and various indices of maintainability. Machine performance and reliability are discussed relative to cumulative tons (machine age) produced and production rates (machine loading). It was determined that performance can be significantly improved given preventive maintenance programs that will increase machine availability.

Jan 1, 1976

By William Catron

This paper is one of a series being prepared by the United States Bureau of Mines on mining methods, practices, and cuts in the various reining districts of the United States. The mining methods described are those used in the mines of the Cananea Consolidated Copper Co., a Mexico corporation whose holding company in the United States is the Greene Cananea Copper Co. The mines are at Cananea, Sonora, Mexico, 25 miles directly south of the international boundary, approximately in 31° nor to latitude and 110 to 130° west longitude. Cananea is connected with the boundary towns of Naco and Nogales, Ariz., by a standard-gage railroad.

Jan 1, 1930

This publication summarizes, for all interested parties, the research, development, and demonstration in-house projets programed by the Bureau of Mines for fiscal year 1980 (October 1, 1979 - September 30, 1980) under its Minerals Health and Safety Research program. The objective of these projects is to provide an ordered and sequenced series of advances toward the Bureau's overall goal of providing the system technology required to create a healthier and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1980

By S. M. Runke

An earlier Bureau of Mines report4/ reviewed and summarized all reports of investigations dealing with the coarse grained pegmatites of the Black Hills of South Dakota to dune 1951. It was proposed, and the hope was expressed in this report, that future progress in the development of the technology of the mining and beneficiation of the pegmatite deposits would be rapid enough to make it possible to issue annual progress reports. Although notable progress has been made in the treatment of pegmatite material, it has not been rapid enough to justify annual reports

Jan 1, 1954

By R. W. Huber, R. C. Wiley, V. C. Petersen

"Three arc- melted ingots, two of a t itanium-7 percent manganese all oy and the third of unalloyed titanium, were forged and rolled into 3/ 4-inch plate; comparative data were obtained on these processes. The finished plate, part of which was used by the Naval Bureau of Ordnance, was tested for mechanical and other properties.These properties were correlated with sponge purity, forging technique, rolling temperature, and cooling rate from the rolling temperature. For the alloy material, transformation data were obtained, and their age-hardening characteristics were studied. The temperature-impact relationship was established for rolled sections from all three ingots.INTRODUCTIONArc -melted ingots of unalloyed titanium and a titanium-manganese alloy were fabricated into plate under closely controlled conditions by personnel of the Metals and Alloys Section, Physical Metallurgy Branch, Bureau of Mines, College Perk, Md. This program was cosponsored by the Naval Bureau of Ordnance. Bureau of Mines interest lay in correlating the processing procedures with the mechanical properties of the finished plate.Considerable data have been published recently on constitution diagrams and properties of titanium-manganese alloys in genera1. 3/ 4/5/6/ However, little if any correlation between processing schedules and end results has been published, particularly with respect to the present commercial production of the proprietary titanium manganese alloys . Several factors in the production of titanium and titanium alloys have a pronounced influence on the physical and mechanical properties of the finished product: (1) The degree and nature of impurities in the base materials, ( 2) the amount of impurities introduced during the melting cycle and their distribution, (3) the homogeneity of the alloy, (4) forging, (5) rolling, and ( 6) final heat-treating cycles. All of these item£ are important from a metallurgical standpoint in producing the desired end properties in the metal."

Mar 1, 1955

By Allen L. Frank

The uranium mine environment is characterized by airborne radon-222 and its daughter products to which miners are exposed through breathing and by gamma and X rays from the uranium-235 and uranium 238 chains to which the miners are exposed externally. The nature of the radon-daughter concentrations and the methods used to define and measure the exposures are explained through an extensive review of the literature. An improved passive track-etch dosimeter for personal use is proposed which has a measurement range of about 30-400 WLH with a 95% confidence interval to ~25% for individual detector measurements in relatively stable mine air. Some measurements of these dosimeters adapted to environmental use are also presented. A program of development for enhancement of dosimeter sensitivity and greater accuracy of measurement is outlined. Extensive gamma-ray survey measurements were made in two Colorado and three New Mexico mines. Follow-up personal miner dosimetry with LiF TLDs was done at the mine with the highest exposure rates, The average miner exposure rate measured was 4.27 mR per day, or 9.3 of the maximum permissible level averaged over 13 weeks. Comparisons are made with previous mine surveys and their value in estimating miner exposure is discussed. Some depth-dose measurements made using Lucite as the absorber are evaluated.

Jan 1, 1978