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By Fred W. Johnson

The first section of this circular has been prepared with a view to answering inquiries frequently received by the Bureau regarding laws governing the staking of claims and regulations covering requirements for holding them and obtaining title in fee to placer ground. These laws and regulations were summarized briefly in Information Circular 6796, "Placer Mining in the Western United States." These laws, however, are administered by the General Land Office, Department of the Interior, and it has been considered advisable to combine an authoritative résumé thereof by the Commissioner of that Bureau with information on small-scale placer mining previously published by the Bureau of Mines. The second section of this circular is largely a revised reprint of Information Circular 6611, "Small-Scale Placer Mining Methods", first published in April 1932 for the purpose of answering the many daily inquiries then being received on this subject. This circular has been reprinted repeatedly, and about 30,000 copies have been distributed, most of them in response to applications therefor. At present (June 1937) requests for this publication continue to be received daily.

Jan 1, 1938

By John F. Elliott

Because of the importance of the steel industry in the economy, a program of study was undertaken to develop a computer model by which it would be possible to predict the need of the industry for raw materials and energy in the next several decades. This report gives the results obtained it a preliminary 6-month program.

Jan 1, 1973

By H. P. Rue

The Bureau of Mines has recently collected two samples of crude oil from wells in the Greasewood Flat area of northeastern Colorado. Sample 31310 was taken from the Continental Oil Co.'s well Briggs No. 1 which care in or September 27, 1931, with a maximum production of 940 barrels per day. Sample 31311 was taken from tie Reiter-Foster Oil Co. Is well Ida Johnson No. 1 which came in on August 24, 1931 with a maximum production of approximately 1000 barrels per day.

Jan 1, 1932

By Robert H. Peters

This report presents a literature review conducted by the U.S. Bureau of Mines. The review summarizes what has been learned from recent empirical studies of the relationship between mine safety and characteristics of miners, mine management, and mining companies. The review is based on literature published in the United States during the period from 1976 to 1988. In addition to summarizing the empirical findings, this report discusses the implications and limitations of these studies, and gives recommendations for improving mine safety. An annotated bibliography section appears in the appendix.

Jan 1, 2009

By Andrew M. Leszcykowski

This report represents the first comprehensive accounting of lode mining sites in the Sheep Mountain mining district, Custer County, Idaho. Twenty-one mine and prospect locations have been added to the Bureau's Mineral Industry Location Subsystem (MILS) data base as a result of initial phases of a mineral appraisal of the River of No Return Wilderness; previously known locations were checked and the updated information added to the data base. The district's deposits are mainly confined to metasedimentary xenoliths in granodiorite and quartz monzonite. Those deposits in the north and west parts of the district are lead-silver-zinc replacement veins in dominantly calcareous facies; those in the southern part of the district are polymetallic fissure-veins containing pyrite, chalcopyrite, arsenopyrite, galena, and sphalerite hosted by micaceous schist and phyllite. The dominant structural trend in the southern part of the district is northwesterly and on strike with major deposits in the adjacent Seafoam mining district.

Jan 1, 1983

By Charles B. Carpenter

In general terminology, the West Texas Permian Basin companies the area south of the Texas Panhandle and west of the Bend Arch or Central Basin region. It is outlined more definitely by geologists however, as that area underlain by the south half of the Permian Salt Basin4/ and includes Scurry, Mitchell, Sterling, Howard, Glasscock, Reagan, Crockett, Upton, Midland, Martin, Gaines, Andrews, rotor, Crane, Pecos, Ward, Winkler, and Loving Counties in Texas, and.. Lea and Eddy Counties in New Mexico. The oil fields of the area, of which more than 70 have been discovered, are shown in fire 1. Approximately 4,200 producing oil wells have been drilled in these fields. Oil has been produced from limestones and dolomites of Permian age in most of the fields in the West Texas Permian Basin. Some of the fields produced oil from sandstone beds above the limestone, and in two fields production has been found below the limestone in formations of Ordovician age.

Jan 1, 1936

By Charles B. Carpenter

In general terminology, the West Texas Permian Basin comprises the area south of the Texas Panhandle and west of the Bend Arch or Central Basin region. It is outlined mere definitely by geologists, however, as that area underlain by the south half of the Permian Salt Basin4/ and includes Scurry, Mitchell, Sterling, Howard, Glasscock, Reagan, Crockett, Upton, Midland, Martin, Gaines, Andrews, Ector, Crane, Pecos, Ward, Winkler, and Loving Counties in Texas, and Lea and Eddy Counties in New Mexico. The oil fields of the area, of which more than 70 have been discovered, are shown in fire 1. Approximately 4,200 producing oil wells have been drilled in these fields. Oil has been produced from limestones and dolomites of Permian age in most of the fields in the West Texas Permian Basin. Some of the fields produced oil from sandstone beds above the limestone, and in two fields production has been found below the limestone in formations of Ordovician age.

Jan 1, 1936

By Fred N. Kissell

In This Chapter [Instruments available to measure methane in mines and tunnels Using a portable detector in both accessible and restricted spaces Machine-mounted monitors: placement and response time Calibration of catalytic detectors for different gases and Misinterpreting warning signs This chapter gives guidelines for methane measurement in mines and tunnels. The emphasis is on the measurement procedure and the interpretation of the measurement rather than on the instrument itself.] The failure to properly sample for methane is a major contributing factor to methane explosion risk. Sampling errors are most likely to occur at mines or tunnels where the presence of methane is not suspected or during nonroutine tasks at mines or tunnels known to have gas. More specific information on methane sampling at continuous miner sections is in Chapter 3. Chapters 4 and 5 discuss sampling at longwall sections, and Chapter 14 discusses sampling at tunnels. METHANE DETECTORS FOR MINING Many models of gas detectors are available to measure methane concentrations, as well as most of the other contaminant gases found in mines and tunnels. An example is the iTX Multi-Gas Monitor, a portable gas detector available from Industrial Scientific Corp., Oakdale, PA. This handheld instrument measures several gases simultaneously. The cost (2004) ranges from $1,300 to $2,200, depending on the number of gases measured. Similar instruments are available from other manufacturers. Most methane detectors used in mining use a catalytic heat of combustion sensor to detect methane and other combustible gases. These have been proven through many years of reliable operation. For detection of methane, proper operation of catalytic heat of combustion sensors

Jan 6, 2006

Objective: To help prevent squeezes, collapses, and other pillar failures through better pillar design, thereby enhancing safety for underground mine workers.

Jul 1, 1997

By W. S. Landers

Nine high-volatile bituminous Utah coals were carbonized singly and in blends with low-and medium-volatile bituminous coals. Of the 9 coals, 2 are in commercial use as the base coals in blends that produce industrially accept-able metallurgical coke, while 7 are regarded as weakly coking and are not used commercially in coking blends. The carbonization tests were made in a la-inch diameter, cylindrical retort, using 50-pound charges. Sunnyside coal blended with autogenous char generally produced larger and stronger coke than was yielded by straight Sunnyside coal. The volatile matter of the char and the concentration of the char in the blend appear to be important parameters influencing coke size and strength. A blend of 10 per-cent autogenous char of 7.2-percent volatile matter with Sunnyside coal yielded coke that was larger, stronger, and of higher apparent specific gravity than coke produced from an industrial coke oven blend consisting of 15 percent medium-volatile coal and 85 percent Sunnyside coal.

Jan 1, 1967

By Nirander M. Safaya

Revegetation success on surface mined lands is dependent upon the nature of the plant growth media. Soil physical and chemical properties dictate the needs for specific reclamation and subsequent management practices. Field experiments were conducted at six coal mine sites in Oliver and Mercer Counties, North Dakota to determine the subsequent effects of a single application of selected amendments on spoil and topsoils over the five year period, 1974-1978. Considerable variations in the physical and chemical properties were found in mine spoils from site to site. The texture of spoils ranged from sandy clay loamy at North Beulah I to loamy at Glenharold, and from sandy loamy at North Beulah 3 and South Beulah sites to loamy sands at the Center site. The pH of the sites ranged from 6.5 at South Beulah to 8.2 at North Beulah 3. In many cases, the pH values of mine spoils were not significantly different from the topsoils. The electrical conductivity (ECe) did not exceed 6 mmhos cm-1 at the test sites even though in other studies much higher values were recorded in the same vicinity. The spoils from Glenharold and North Beulah test sites can be classed as moderately saline, and those from Center and South Beulah as non-saline. The sodium adsorption ratios (SAR) varied from less than 1 to 32, with highest values in the spoils of North Beulah 3 followed by Glenharold; all other sites were nonsodic. Lowest SAR values (less than 1) were found in the topsoiled sites at South Beulah and Center. Spoils of North Beulah 3 test site were highly calcareous, followed by North Beulah 2 and Glenharold. Center mine spoils which were the least calcareous of the test sites, showed the calcium carbonate equivalent three times higher than that of the topsoil. The average calcium concentrations in the spoils of North Beulah 3 and South Beulah test sites were -13 and 14 me 100g -l while at North Beulah 2 and Glenharold test sites 25 and 22 me 100-1-1 were recorded, respectively. The overall magnesium concentrations ranged from an average of 4 to 16 me 100g 1. Sodium concentrations in all sites never exceeded 10 me 100g-1. Phosphorus concentrations on the average at North Beulah 1, North Beulah 2, and Center were 10.2, 4.6, and 22.2 µg g -1 spoil, respectively. Concentrations of potassium ranged from 200 ppm at South Beulah site to more than 375 pp in at the Glenharold site. High concentrations of sulfates (239-2778 µg g-1) seem to contribute to the salinity in these spoils. Chloride concentrations of spoils were low and never exceeded 40 µg g-1 spoil. Based on established critical levels of deficiency for micronutrients in agricultural soils, it seems that none of these were deficient. However, controlled environment experiments did reveal increased plant growth responses when some micronutrients were added to the mine spoils. Treatment effects were highly site specific depending on the nature of the soil/spoil characteristics and, of course, the properties of the various treatments. While slack coal amendment to the spoils at North Beulah 2 site affected significant increases in a large number of variables (both major and trace elements), amendment of the topsoils at the South Beulah test site with leonardite resulted in significant decreases in a number of variables, particularly trace elements. Spoils at Glenharold and North Beulah 3 demonstrated the fewest significant changes due to amendments. Calcium, magnesium, strontium, organic matter and nitrogen were consistently increased from site to site with the addition of lignitic materials. Other spoil/topsoil physical and chemical properties (30 variables) as affected by amendments and time are discussed.

Jan 1, 1982

Case 1: A driller raised a drill rig mast into a 7200-volt overhead power line. Both he and his helper were killed. Case 2: A driller-helper was pulling a winch cable toward a stack of drill steel when the cable contacted a 12,000-volt power line. The helper was killed, and the driller at the rig controls was severely injured. [ ]

Jan 1, 2006

Empirical methods involve the scientific interpretation of real-world experience. Many problems in ground control lend themselves to an empirical approach because the mines provide us with plenty of experience with full-scale rock structures. During the past 10 years, powerful design techniques have emerged from statistical analyses of large databases of real-world pillar successes and failures. These include the Analysis of Retreat Mining Pillar Stability (ARMPS), the Analysis of Longwall Pillar Stability (ALPS), the Mark-Bieniawski rectangular pillar strength formula, and guidelines for preventing massive pillar collapses. In the process, our practical understanding of pillar behavior has been greatly enriched.

Jan 5, 1999

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982

By S. M. Marshall

The investigations recorded in this bulletin were conducted by the Pacific Coke & Coal Co. in cooperation with the United States Bureau of Mines and the University of Washington. They cover one phase of a comprehensive investigation to determine whether coals from an extensive, undeveloped area of Pierce County, Wash., can be used in the manufacture of coke for the iron blast furnace. The completed investigation had three parts: (1) A geological survey of the coal property, (2) washing and crushing tests of the coals, and (3) coking and by-product tests. The geological survey, which was not conducted in cooperation with the Bureau of Mines and the University of Washington, included systematic tracing of the coal beds by test holes throughout the property, except some portions covered by an impenetrable layer of glacial drift. By this means all of the beds were correlated, their thickness and general character were determined, and tonnage estimates were made. Only such parts of the survey results as are necessary to a full explanation of the investigations described herein are included in this bulletin.

Jan 1, 1931

By John E. Trombly

System objectives and design criteria for an in-mine ULF radio paging system are discussed Coding formats, frequency and bandwidth selection criteria leading to the system design are discussed. The prototype call alert transmitter and pocket page receiver is functionally described. The report includes circuit descriptions, schematics, parts lists, printed circuit fabrication and assembly drawings. The report concludes with an estimate of the manufacturing cost for each assembly.

Jan 1, 2011

By L. J. E. Hofer

THIS BULLETIN analyzes and summarizes research at the Bureau of Mines dealing with the preparation, properties, and reactions of iron carbides in the period 1948-60, part of which was sponsored by Wright Air Development Laboratories. The objective was to develop better catalysts for the synthesis of methane and higher hydrocarbons from hydrogen and carbon monoxide. The investigations resulted in the first adequate characterization of epsilon iron carbide, which later proved to be an important intermediate in the tempering of martensite in steel. At temperatures near 170° C, the carbon in carbon monoxide reacts nearly quantitatively with finely divided alpha iron to form an iron carbide in which the metal atoms occupy the positions of the close packed hexagonal arrangement with lattice parameters of ao=2.754 A and co=4.349 A. The carbide has a composition within 2 atomic percent of that required for the formula Fe2C, a Curie point of about 370° C, a specific magnetization of 160.4 ergs per gauss-gram Fe at 50° C, and a ferromagnetic moment of 1.70 Bohr magnetons. Epsilon iron carbide can be converted to chi iron carbide by thermal treatment at 343° C for about 70 hours. The chi iron carbide so formed has a Curie point of 247° C, a specific magnetization of 142.5 ergs per gauss-gram Fe at 50° C, a ferromagnetic moment of 1.72 Bohr magnetons per iron atom, and a paramagnetic moment of 5.5 Bohr rnagnetons per iron atom. Direct synthesis of this carbide from carbon monoxide at 240° C indicates a composition within 7 atomic percent of that required for Fe2C. Chi iron carbide can be converted to cementite at 550° C in about 315 minutes. The theta iron carbide so prepared has a Curie point of 210° C, a specific magnetization of 147.3 ergs per gauss gram Fe at 50° C, a ferromagnetic moment of 1.72 Bohr magnetons per iron atom, and a paramagnetic moment of 3.9 Bohr magnetons per iron atom. Pure chi iron carbide reacts to form theta iron carbide by the elimination of free carbon. In the presence of an excess of free iron in intimate contact with the carbide, chi iron carbide reacts with the free iron to form theta iron carbide. The second reaction proceeds at an appreciable rate at 320° C and can be used to snythesize finely divided theta iron carbide with no free-carbon impurity at low temperatures. The ease of the reaction in the presence of free iron suggests that chi iron carbide is an intermediate in the tempering of epsilon iron carbide to theta iron carbide as it proceeds in steels. Experiments on carbon steel show that the magnetic moment of the iron atoms in martensite is about 2.2 Bohr magnetons per atom, a value approximately the same as that of the iron atoms in alpha iron. The Curie points of epsilon iron carbide, chi iron carbide, and theta iron carbide were found -in various specimens of tempered steel to be 10° to 20° C lower than normal values. This shift is probably the result of manganese in solid solution. Preparations of various compositions of epsilon iron carbonitrides show many effects of extensive isomorphism between epsilon iron carbide and epsilon iron nitride. The action of carbon monoxide on finely divided alpha iron at 400° C results in free carbon deposits containing filaments about 0.1 micron in diameter and several times as long. The filaments are characterized by nuclei of dense material located midway from each end of the filament. Although carbiding to near completion at 240° C over periods of about 300 hours produces a preparation containing no appreciable percentage of epsilon iron carbide, very brief periods of carbiding of the order of a minute result in the formation of detectable epsilon iron carbide even at temperatures as high as 325° C. The data indicate that epsilon iron carbide is an intermediate in the formation of chi iron carbide during its formation from carbon monoxide in the gas phase. Attempts to convert cementite to chi iron carbide by cold work increased the Curie point but did not change the X-ray powder diffraction pattern.

Jan 1, 1966

By B. F. Naylor, C. H. Shomate, F. S. Boericke

"Ilmenite is the most important titanium-bearing constituent of titaniferous iron ores. Such ores, of which the United States has abundant reserves, are of interest because they constitute an important potential source of both iron and titanium that may be tapped in times of stress, and which eventually may be utilized in the normal course of events.As the iron and titanium constituents of titaniferous iron ores are not completely separable from each other by ore-dressing methods, any process for metal recovery will, of necessity, involve reduction of the iron in ilmenite. Consequently, knowledge of the thermodynamic properties of ilmenite should supplement information already available concerning those ores. With this in view, the Pacific Experiment Station of the Bureau of Mines undertook to evaluate thermodynamic properties; the data obtained are the subject of this report.Three types of experimental work were involved. First, low-temperature specific heats of ilmenite were measured in the temperature range 500 to 29S° K. These data serve to evaluate the entropy, a quantity necessary for a reliable evaluation and correlation of other thermodynamic properties. Second, high-temperature heat-content measurements were made in the temperature range 298° to 1,743° K. The data serve to bridge the gap between room temperature and elevated reduction-process temperatures. Finally, hydrogen-reduction equilibria were measured in the temperature range 1,220° to1,375° K. These data-give a direct measure of the free energy of reduction of ilmonite at these temperatures and, in conjunction with results of the other two types of measurements, serve to obtain the heat of formation of ilmenite, a quantity not readily determinable by direct calorimetric means.The data are correlated to form a composite, self-consistent portrayal of the thermodynamic properties of ilmenite, which may be used in evaluating the efficacy of any reducing agent of known thermodynamic properties. Selective-reduction of iron in ilmenite by hydrogen, carbon monoxide, and carbon are considered in this report."

May 1, 1946

By John P. Hansen

Batches of red or brown iron ore concentrates, weighing 100 or 200 grams, were reduced with gaseous reductants in a laboratory-sized fluidized-bed reactor. Using a loss of weight technique, the rates of reduction were measured and the effects of temperature, gas consumption, and gas flow rates were determined. Below about 725° C the rate of reduction was controlled by the chemical reaction at the reduction interface having an activation energy of about 10 kcal/g mole. Above about 725° C the rate of reduction appeared to be controlled by the flow of the gaseous reductant and therefore to be directly proportional to the flow rate. Above 725° C, hydrogen reduced the iron ore much faster than carbon monoxide. In gas mixtures, carbon monoxide or nitrogen reduced the hydrogen partial pressure and lowered the reaction rate proportionally. When present in large concentrations, carbon monoxide had a serious inhibiting effect on the reduction rate, probably owing to carburization and sintering of the reduced iron.

Jan 1, 1970

By D. A. Stanley

The Bureau of Mines conducted laboratory-scale experiments to determine whether or not surface waters with a high organic content could be purified sufficiently to be used to replace the natural high-quality deep well water currently being used in the silica flotation step of phosphate rock beneficiation. Waters abundant in organic matter were collected from two central Florida streams, flocculated with a cationic polyethylenimine polymer, and processed in a sand filter. This treatment removed most of the organic materials from the water. Untreated surface water, treated surface water, and distilled water were used to compare the flotation response of the acid insolubles in an amine flotation circuit. Surface water treated with PEI-1000 was shown to be as effective as distilled water for the acid-insoluble-flotation step. Flocculation and filtration can therefore produce water suitable for amine flotation of quartz, which would permit substitution of surface water for deep well water.

Jan 1, 1981