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By D. J. Bauer, V. E. Shaw

Bastnasite concentrate was processed to recover total rare - earth content and obtain high - purity ceric nitrate . Reaction of the concentrate with 45 percent caustic soda for 1 hour at 180 ° C in stainless steel vessels resulted in 99 - percent conversion to rare - earth hydroxides . A drying step followed by solution in nitric acid produced a tetravalent cerium fraction amenable to extraction with TBP . Single- stage separatory funnel experiments resulted in 90 -percent recovery of ceric nitrate at a purity of 99.9 percent . Fractional extraction in pressure - bubbler columns resulted in 98.5 - percent recovery of 99.5 -percent - pure ceric nitrate .

Jan 1, 1964

In 1987 Wyoming became the largest coal producing state in the country. The state is known for its extensive coal resources and extremely thick coal seams. Wyoming's coal reserves total about 69.3 billion tons, or 14.2 percent of the U.S. coal reserve. Coal seams range generally from 10 to 80 feet in thickness, although one seam is 220 feet thick. The coal-bearing areas of Wyoming underlie approximately 41 percent of the state's total land area. Wyoming's coal ranges from lignite to high volatile bituminous. Most of the coal produced is subbituminous from the Powder River coal region near Gillette. The presence of coal in Wyoming was discovered before 1834 on the Belle Fourche River. The state's first mine opened in Carbon County in 1865, and with the completion of the trans- continental railroad, the demand for coal increased. Currently approximately 80 percent of Wyoming's coal production is shipped out-of-state to meet the growing demand for low- sulfur coal to fuel electric generating plants. Wyoming received conditional regulatory approval November 26, 1980. Its Abandoned Mine Land Program was approved February 14, 1983.

Jan 1, 1992

By William J. Douglas

This document describes the development of a conventional mining equipment data base, and an approach for conducting industrial engineering studies of arbitrary mining systems employing network techniques. Data was acquired through underground time studies. Each member of a four-man field team was assigned to a specific machine during each shift for which observations were conducted. Using digital wrist watches and networks describing the man-machine interactions, all events occurring luring the course of each shift were recorded on cassette tapes. The tapes were transcribed, coded, keypunched, and validated using computerized editing techniques. The resulting data files were processed to provide statistics relating to activity durations and event frequencies. The results were used to evaluate operator, machine, and system performance for each section which was observed. Equipment, reliability, and maintainability analyses were conducted using the industrial engineering data files in conjunction with historical information collected at the mine site.

Jan 1, 1976

By P. C. Good

This Bureau of Mines report describes the preparation of phosphoric acid directly from phosphate ore, without prior beneficiation, in a small-scale, continuous process research unit, as part of an effort to improve minerals and metals recovery from domestic resources while minimizing environmental effects. Three phosphate-matrix samples, ranging in grade from 18.2 pct P20S5to 11.9 pct P205, were dry-fed at a rate of 1.82 kg/hr (4 lb/hr) to a continuous-circuit, 12-liter, single-tank digester to yield phosphoric acid and byproduct gypsum filter cake. Comparison with earlier data shows that a significantly improved filtration rate was attained in a single-tank reactor compared with that attained in a five-tank reactor train processing the same ore. Iron and aluminum impurities in the product phosphoric acid averaged about 60 pct higher than amounts reported in commercially prepared, concentrate-derived acid. All gypsum filter cakes prepared had a firm, sandy texture, rendering them physically suitable for stacking or landfill use. Introduction of dry attritioning and air classification approximately doubled the attainable filtration rate when the dry-beneficiated product was digested. In air classification, there was a 12-to 14-pct P205 loss. Depending on the technique used and the matrix grade, overall P205 recovery ranged from about 72 to 89 pct.

Jan 1, 1979

By W. W. Adams

With production of coal per man-hour of work at a higher level than ever before, the coal-mining industry of the United States established a near-record in lowering the accident rate of nonfatal injuries per million man-hours of exposure in 1940, the injury rate being lower, except for 1939, than in any year since 1930, the first year for which comparable figures for nonfatal accidents were collected by the. Bureau of Mines, United States Department of the Interior. The rate for fatal accidents, on the other hand, was not as low or favorable as in 1939, nor was it as low as in many years since 1910, the earliest year for which fatality rates were complete for all coal-mining States. Accident and employment reports received from mine operators and fatal-accident reports from State mining departments and inspectors showed that 533,267 men were employed at coal mules in 1940, exclusive of the number employed at coke ovens, Although this number represented 6,108 fewer employees than in 1939, a large increase was made in the volume of work performed and in the quan¬tity of coal produced. In 1940 the amount of labor performed at coal mines was 748 million man-hours, a gain of more than 10 percent over the previous year. The average employee worked 199 days, an increase of 20 workdays per man. Production of coal was nearly 513 million tons, an increase of 14 percent, of which more than 461 million tons was bituminous coal and more than 51 million tons was Pennsylvania anthracite. Accidents to mine workers caused the death of 1,388 employees; in addition, 59,781 employees were injured, and each injury resulted in disability of the employee for more than the remainder of the day on which the accident occurred.

Jan 1, 1942

By H. F. Feldmann

This work was done to provide thermodynamic, electrical, physical, and compositional data on the seeded combustion plasmas of seven coals for the design of MHD generators. The systems were assumed to be at equilibrium, and the design data were generated by solving for the composition of both gas and liquid phases with a digital computer. The coals reported in this study include a western subbituminous, a Pennsylvania anthracite, and five representative bituminous coals. The data include dewpoint temperatures of both slag and seed. A Mollier diagram for each coal is given to allow graphical generator calculations.

Jan 1, 1970

The coal-bearing regions of Colorado cover approximately 29,600 square miles, which is 28.4 percent of the state's total area. The most important coal-bearing regions are located in the north western and west-central parts of Colorado. Coal resources vary from lignite to anthracite. More than 70 percent are bituminous; 23 percent subbituminous; 5 percent lignite; and less than 1 percent anthracite. The state's coal reserves total about 17.2 billion tons, 3.5 percent of national reserves. Approximately 8.8 million acres of coal rights in the state are owned by the Federal Government; on about 72percent of this land, the Federal Government controls both the coal and the surface rights. It is estimated that approximately 4.2 billion tons of coal reserves are under federal ownership in Colorado. Permitted acreage of mines in Colorado ranges from 40 to 13,114 acres. Differences in elevation create many climatic zones in Colorado. Local annual precipitation can average less than eight inches in some areas in extreme western Colorado to more than 30 inches in certain mountainous areas. Generally, precipitation rates are low at most mine sites, making revegetation difficult. Colorado gained primacy when its regulatory program was conditionally approved December 15,1980. The Abandoned Mine Land Program was approved June 11, 1982.

Jan 1, 1992

By Raymond P. Miller

This two volume report addresses slope stability of surface mine spoils within the Interior Coal Province. Sixteen (16) mines were visited, pertinent data and samples collected, and reported spoil instabilities back-analyzed. Laboratory test results are compared to back-analyzed material properties. Available methods of slope stability analysis are reviewed and evaluated with respect to application to mine spoil stability evaluation and prediction. Correlation and tentative relationships among spoil material properties, highwall conditions, mining equipment and procedures and empirical observations are presented. Slope stability sensitivity plots illustrate the relative significance of various input parameters on stability. Slope stability input parameters are correlated with site and mining conditions to identify the primary factors controlling spoil stability. Investigative methods, spoil stability enhancement techniques, spoil stability prediction procedures and future study areas are discussed. Appendices include a glossary of terms, annotated bibliography, details of mine visits, and detailed laboratory test procedures and results.

Jan 1, 1979

By Robert W. Geehan

"INTRODUCTION The Bureau of Mines has been investigating deposits of critical and essential minerals in the United States since 1939. Many of the mines were developed.A preliminary examination of the Sultan mine was made in January 1945 by the author, who recommended investigation by drifting and crosscutting. The Bureau conducted a project at the mine from April to June 1946. Claims investigated are in sec. 20, T. 25 S., R. 58E., Mount Diablo base and meridian, in southern Clark County, Nev., about 7 miles southwest of Good-springs.The Sultan mine has been an intermittent producer of zinc-lead-silver ore since 1910. During World War II, ore was shipped to the Government stock pile at Jean, Nev., and to the International Smelting& Refining Co.'s smelter near Salt Lake City, Utah. Throughout the past year, ore has been milled and the concentrates have been shipped to the smelter."

Sep 1, 1947

By Michael K. Phang

The use of explosives to fragment rock generates ground vibrations which may have a detrimental effect on contiguous underground coal mine openings. Increased surface blasting by a burgeoning number of surface coal mines and quarries has caused considerable concern among underground mine operators. Ground vibration effects generated from surface mine blasting are also causing public concern. In response to this concern, the U.S. Bureau of Mines (Stagg and Engler, 1980) has measured and analyzed ground vibrations and their effects on underground and surface structures. Some of the complaints registered against the mining industry are claims of substantial material damage from vibrations generated by the blasting; others are nuisance complaints of minor damage or annoyance. In general, allegations of damage from surface blasting have been sufficiently numerous to constitute a major problem for mine operators engaged in blasting operations. They have recognized the need for more technological data to evaluate the vibration problems associated with blasting. Both the operators and the general public need adequate safeguards based upon factual data to protect their specific interests. The coal mine industry needs reliable information from which to change blasting operations to reduce the number and severity of major damage claims and eliminate the growing number of nuisance complaints. The problem is of major concern not only to coal mine operators and nearby property owners, but also to federal, state and local governments. At the same time, environmental control agencies responsible for blasting and explosives use require reasonable and appropriate guidelines to protect the miners' lives.

Jan 1, 1984

By WM. H. RINKENBACH, C. A. Taylor

No complete work on explosives, their constitution and analysis, has hitherto been published. Several books that contain chapte.r;s on analysis do not cover the matter thoroughly. Methods tha;t, manu~ facturers, testing stations, and other . agencies have developed to meet their own requirements have not been made public. The Bureau of Mines has issued four publications 1 - cov:eri:ng special phases of the subject. This bulletin. is not inte.nded to replace those reports, but rather to cover present methods employed 'in the , industry and to include all classes of explosives and the materials used in their manufacture. No sharp distinctions can be drawn between classes of explosives. . Surplus military explosives, for example, may be used for blasting, just as blasting explosives, under some conditions, may be employed for military purposes. Moreover, one class gradually merges into another because of similarity in composition. Explosives are here grouped as dynamites, black powders, propellants, detonators, and primers. Some materials are used in practically all these groups ; others in only one. To discuss all the materials that have been or that may be used and the methods for their identification and quantitative determination is not feasible, but the methods described will probably suggest ways of examining new mixtures.

Jan 1, 1923

By John P. Powell

The increasing demands for petroleum and its products and the steadily increasing cost of discovering and developing new oil fields are factors that emphasize the importance of increasing the recovery of oil from known petroleum reserves. Water flooding is a valuable conservation measure, not only preventing premature abandonment of stripper leases but also reviving interest in many areas previously abandoned. The use of water flooding as a means for recovering additional oil from partly depleted oil-bearing formations was first tried in Oklahoma in 1931. Early water-flooding operations were confined to the area of shallow Bartlesville-sand formations in Nowata and Rogers Counties, where many of the projects were outstandingly successful. The results of these operations stimulated activities in other pools in Oklahoma, and by the end of 1949 water flooding had been tried in 25 of the 49 oil-producing counties in the State (fig. 1). Approximately 33 million barrels of oil, or 1,806 barrels per acre, had been recovered by December 31, 1949, from 18,221 productive acres included in the 162 active and abandoned projects in Oklahoma by injection of approximately 449 million barrels of water.

Jan 1, 1951

Five watersheds, ranging in size from 29 to 49 acres, were selected in East-Central Ohio to investigate the hydrologic and water quality conditions occurring before, during, and after surface mining. Four of the watersheds will undergo surface mining, involving either the Number 6, 9, 11, or 8 coal seams, and one watershed having an outcrop of the Number 6 coal will be operated as a control watershed. To determine the premining hydrologic and water quality conditions (Phase 1), physical information was obtained for each watershed and instrumentation was installed for obtaining hydrologic data and water quality samples. In addition to topographic maps, soils and vegetation maps were prepared. Stratigraphic columns were developed from geologic cores; networks of observation wells and of soil moisture access tubes were installed; and weather stations were established to measure temperature, humidity, wind and solar radiation, and to collect precipi¬tation samples. Field data were collected over a 10-month period for one watershed and for about 8 months on another watershed before surface mining began. The other watersheds continued in the premining data phase. These data were for precipitation, temperature, relative humidity, wind speed, solar radiation, snow and frozen soil, soil moisture, infiltration (rainfall simulator), spring discharge, runoff from watersheds, and ground-water levels. Also, samples of runoff and ground water were obtained for chemical analyses and additional samples of runoff were acquired for suspended sediment load determinations. Over the study period, precipitation was not very representative of the long term averages, but data are available from the control watershed for a representative 7 year period which should prove invaluable in modeling the hydrology of the project watersheds for the premined conditions. Spring discharges (before mining) from the upper aquifer of two of the watersheds averaged only 508 and 652 gallons daily. The proportion of precipitation occurring as surface runoff from the large watersheds ranged from 8 to 36 percent and the peak discharges from 5.86 to 81.95 cfs. Base-flow and runoff water samples from four of the watersheds (unmined conditions) were collected and analyzed quantitatively for 39 water quality parameters. Monthly precipitation samples sediment fractions of the base flow and runoff were analyzed for 22 and 17 parameters, respectively. The average concentrations of the water quality parameters for the watersheds (unmined), except for suspended solids, were as low or lower than the EPA recommended maximum allowable concentrations in drinking water. Several parameters in precipitation equaled or exceeded the levels of corresponding parameters in runoff water. The average concentration of suspended solids in storm runoff ranged from 118 to 1110 mg/l, and for base flow the range was from 44 to 247 mg/l; the higher concentrations were associated with the watersheds exhibiting the greatest disturbance. Iron ranged from an average of less than 3 µg/1 to 228 µg/1. Manganese ranged from less than 41 µg/1 to 334 µg/I. Ground-water systems (unmined condition) are described for the five project watersheds. Each watershed was found to have two major perched aquifers within the top 250 feet. Generally, these perched aquifers involve local flow systems, though flow across watershed boundaries in some areas. Recharge is mostly from local precipitation and discharge is mostly as spring flow, base flow, evapotranspiration, and leakage through the underlying confining bed. Shallow ground water was commonly of the calcium bicarbonate type. Although dissolved-solids concentration was generally 200 to 600 mg/1, brackish or salty ground water was present in several areas. A composite hydrologic model for the project watersheds will consist of separate ground-water, unsaturated flow, overland flow, and evapotranspiration component models. The ground-water model (a modified quasi-three--dimensional U. S. Geological Survey model) operates on a grid network and the newly formulated unsaturated flow model was divided into overlying prismatic elements for numerical solutions. The unsaturated flow model includes provision for incorporating the evapotranspiration model. An available distributed kinemetic overland flow model was utilized. An analyses was made of one of the costs of reclaiming coal mines; the legal and administrative costs of complying with legislation. Such costs borne by coal companies under the Ohio law are thought to be a surrogate of these costs under the new Federal law. Regression analyses were used to relate the legal and administrative costs to acres in the permit and the tonnage of coal produced.

Jan 1, 1978

By M. C. Chapman, P. L. Swanson, A. T. Iannacchione

The National Institute for Occupational Safety and Health (NIOSH) evaluated microseismic activity from three field sites to compare and contrast the characteristics of microseismic emissions from very different geologic, stress, and mining environments. Recently, NIOSH has embarked on a research program to evaluate the use of microseismic monitoring information to identify roof fall failure processes and to assess its potential to warn of unstable roof conditions. Large roof instabilities, such as roof falls and certain roof caving events, have proven difficult to anticipate representing an increased risk to miners working in these inherently hazardous areas. When local failure processes are better understood, appropriate control measures can be engineered to mitigate these hazards. This study used microseismic emissions to help identify three local rock failure processes. It was also shown that analysis of microseismic emissions can aid in assessing the degree of instability associated with these local rock failure processes.

By G. L. Oldright, John D. Sullivan

"The present article is the second of a series of papers dealing with the dissolution of copper minerals in various reagents. Work done on the problem has been carried out at the Southwest Experiment Station of the United States Bureau of Mines, in cooperation with the Department of Mining and Metallurgy, University of Arizona. The first paper4 dealt with the dissolution of azurite, malachite, chrysocolla, and tenorite. Preceding articles5 have also dealt with other factors involved in the leaching of copper ores.Cuprite (Cu20) is usually considered as a mineral which is not adaptable to sulphuric acid leaching. Hofman,6 in describing leaching by sulphuric acid, states: ""Cuprite is decomposed into CuO and Cu; and ore carrying cuprite has to be oxidized (weathering, roasting) before treatment."" Greenawalt7 says: ""When acted upon by dilute sulphuric acid, it is partly reduced to metallic copper and partly oxidized into copper sulphate. When heated with strong acid it is entirely oxidized to sulphate."" Work to be described in this article was undertaken to ascertain the conditions whereby all the copper in cuprite could be converted into the soluble sulphate."

Dec 1, 1929

By W. W. Adams, V. E. Wrenn

"Production of explosives in the United States during the calendar year 1936, as represented by reports of sales by manufacturing companies, totaled 391,604,500 pounds, an increase of 27 percent over the amount produced during 1935. This quantity included 81,698,375 pounds of black blasting powder (granular and pellet), 262,047,106 pounds of high explosives other than permissibles, and 47,859,019 pounds of permissible 5/ explosives.The manufacturers' reports to the Bureau of Mines classify the sales of explosives according to five main classes of work in connection with which the explosives were used.Coal mines used 87 percent of the total amount of black blasting powder sold, bituminous-coal mines 79 percent, and anthracite mines 8 percent; coal mines also consumed 98 percent of all permissible explosives and 9 percent of the high explosives other than permissibles. The coal-mining industry consumed 16 percent more explosives in 1936 than in the preceding year, the increase at bituminous mines being 21 percent and that at anthracite mines 4 percent.Metal mines used 29 percent of the high explosives other than permissibles and less than 1 percent of the black blasting powder and permissible explosives. The total quantity of the three classes of explosives used in metal mining in 1936 was 36 percent more than the quantity so used in 1935."

Jul 1, 1937

Toward the goal of maximizing minerals and metals recovery from domestic resources, the Bureau of Mines, U.S. Department of the Interior, has conducted in situ corrosion studies at the Salton Sea Known Geothermal Resources Area (KGRA) in the Imperial Valley, Calif., to evaluate and characterize materials of construction for geothermal resources recovery plants. General-, pitting, and crevice-corrosion characteristics of 13 commercially available alloys were investigated for periods of 15 and 30 days in seven process environments expected to be found in typical geothermal resources plants. Stainless steel alloy 29.4, Inconel 625, and the Hastelloys G, S, and C-276 were the most resistant to general corrosion, did not pit, and exhibited little susceptibility to crevice corrosion. Stainless steel alloys 430, E-Brite 26-1, and 6X had low general corrosion rates, but pitted and were susceptible to crevice corrosion. Stainless steel alloy 316 L had a low corrosion rate, but corroded intergranularly, pitted, and was susceptible to crevice corrosion and to stress-corrosion cracking. Titanium-1.5 nickel and TiCode-12 had low corrosion rates, did not pit, and were not susceptible to crevice corrosion. Carbon and 4130 steels had high corrosion rates, pitted, and had high susceptibilities to crevice corrosion. The major scale-forming mineral on the corrosion samples in most of the process environments studied was galena mixed with lesser amounts of other minerals.

Jan 1, 1979

By Bertrand L. Johnson

Fertilizers are indispensable to national preparedness and defense. Production of adequate supplies of nourishing food for sustaining life in the United States is absolutely dependent in many parts of the country on the use of artificial fertilizers of various types. Only by using fertilizers can we maintain our present volume of production without great additional expense. Otherwise we would have to increase crop areas constantly to compensate for declining yields, we would have to lower the quality of food marketed, and standards of farm living and rural civilization would decline. About 60 million of the 360 million acres of crops grown annually in the United States Vow require fertilizing each year, and between 7 and 9 million tons of commercial fertilizers are consumed annually for this purpose.

Jan 1, 1941

By Richard E. Thill

The Bureau of Mines' Oil Shale Data- Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra Brake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDB listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

The coal-bearing areas of Kansas cover approximately 18,800 square miles (23 percent of the state's total area). Coal in Kansas ranges from lignite to high volatile bituminous, located principally in the south-eastern part of the state. Kansas reserves are estimated to be 987,500,000 tons, approximately 0.2 percent of U.S. reserves. Coal beds generally occur in thin seams up to five feet thick. The overburden-to-coal stripping ratios in Kansas are among the highest in the nation, typically 20 to 1, with some ratios up to 35 to 1. The first commercial coal mining operation in Kansas opened in 1865 at Fort Scott in Bourbon County. As in other states, coal production in Kansas increased during the industrial revolution, and then fell as industry converted to alternative fuels. Production peaked in 1916 and 1917, with annual production of 7,250,000 tons. Coal production today is by surface mining methods. The Kansas regulatory program was approved April 14, 1982; the Abandoned Mine Land Program was approved February 1, 1982; and the emergency program authority was approved January 10,1989.

Jan 1, 1992