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By D. R. Tesarik

As part of its research program to investigate ways of improving resource recovery and reducing subsidence, researchers from the U.S. Bureau of Mines placed instruments in the B-North ore body of the Cannon Mine, Wenatchee, WA, to monitor cemented backfill and rock deformation during mining. The vibrating-wire gauges proved to be reliable and versatile, and approximately half of the instruments are providing data after 2 years of use. A two-dimensional, finite-element model was used to analyze the Cannon Mine's multilevel bench cut-and-fill mining method and predict rock and backfill displacements. The model accurately predicted rock displacements, but the predicted and measured displacements in cemented backfill had a correlation coefficient near zero, indicating that the model should only be used to predict rock displacements and not backfill displacements. A finite-difference model was also used to evaluate the stability of a cemented backfill pillar. Results can be used to conservatively predict backfill stresses, but on-site observation of pillar failures coupled with in situ measurements are needed to make more accurate predictions. An ongoing evaluation of the mining system has indicated that filling the primary stopes tight to the back with cemented backfill allowed these pillars to carry overburden loads soon after the cemented backfill was placed.

Jan 1, 2010

By M. D. Aldridge

The results of a four-year research effort aimed at developing a practical and effective electronic system for monitoring safety conditions throughout a coal mine by displaying, at a central location, remotely measured parameters are described. This document presents the general philosophy of an experimental system in an operating coal mine. The conclusions drawn from this experience are presented and a typical design for a large coal mine is described.

Jan 1, 1974

By J. P. Walker

"INTRODUCTION Sponge iron has been made commercially since 1912 at a Swedish ceramic plant; and the product, known as Swedish disk-type nagger sponge iron, has an excellent reputation as a superior furnace feed wherever high-grade steels are made.The general procedure for making brickyard sponge iron was described frequent in Swedish technical journals before 1932 and at that time consisted in filling clay refractory containers, called saggers, with iron ore plus the necessary quantity of solid reducing agent and then firing in an ordinary ceramic kiln. Two types of sponge iron were made in this way: (1) An inferior, high-sulfur product obtained by mixing the ore and solid reducing agent; and (2) a high-grade, low-sulfur product made by filling the sagger with alternete layers of unmixed ore and reducer, yielding sintered disks of metallic iron particles.Swedish disk-type sponge iron of interest to the steel industry because it has a very low sulfur content, even when made by the use of low-grade, high-sulfur coals for reducing and firing. The Swedish product also contains little siliceous gangue residue and is almost phos¬phorus-free. To those features must be added the high metallic-iron content -90 to 96 percent - and freedom from even small amounts of the metals that are undesirable in steel making.The details essential for successful operation of this procedure are not known, especially as regards improvements said to have been made since 19;2. The Bureau of Mines therefore decided to determine some of these missing details, and this report records the results of the first set of experiments on the manufacture of brickyard or sagger sponge iron."

Sep 1, 1945

By Raja V. Rarnani, Robert L. Frantz

"The more than 75 research projects funded throughout the first 10 years of the Dust Center's operation have resulted in numerous cumulative findings fulfilling the goals of the Center. These project descriptions present the methodologies and project-to-project relationships leading to their various accomplishments and demonstrate the mesh between project objectives and Center goals.To develop equipment for collecting respirable dust samples.To develop experimental methods for particle-by-particle characterization of morphology, size, and chemistry.To develop experimental methods for overall respirable dust sample characterization of size distribution, chemistry, and crystallography.The project directly addresses the Center's goals to enhance the understanding of the scientific and engineering characteristics of fine and respirable mineral particles found in mining and milling atmospheres and to establish the relationship between natural and cultural factors (mine geology, mineralogy, mining and milling methods, equipment, and control measures) in the generation of fine particles. The project also aims to contribute to the development of control mechanisms for reducing ambient respirable dust concentrations and worker exposures.The work on this project is related to similar work on Coal Mine Dust Characterization (Project No. 2701/MN1) and Characterization of Dust Particles (Project No. 4203/PS3).Airborne dust sampling was performed at the following locations: 1) a sand and gravel quarry in Southern New Hampshire, 2) a welding facility, 3) a ceramic powder facility, 4) a metal powder facility, and 5) the air in Cambridge, Massachusetts. A portable sampling box incorporating two Sierra personal cascade impactors was designed and produced. At a 2-LPM flow rate, the effective cut-off diameters of the Sierra impactors were 10.0, 6.0, 3.5, 2.0, 0.9, and 0.5 mm, respectively, for each stage, and the air passed through a PVC filter after the last stage. In addition, the sampling box contained a total respirable dust filter. The substrates were weighed carefully before and after collection, and the weight increases were recorded. All films, foils, and filters were put in the balance chamber for more than 8 hours to stabilize the temperature and humidity before weighing. A Cash 21 microbalance (±0.001 mg) was used to weigh the Mylar films, SS films, and filters."

Jan 1, 1995

By Joseph J. Wallace

1. The Pittsburgh is the most important bed in Washington County from the standpoint of present production and recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 4,181 million short tons as of January 1, 1954. Of this total, 4,132 million short tons is in beds 28 inches and more thick. Areas in some beds were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1955

By W. J. Fene, G. W. Grove

An important activity of the Safety Division of the Bureau of Mines , in its efforts to reduce accidents , is the safety inspection of mines . Inspections are made at the request of the operators and are not connected with the inspections by the various State departments of mines . The operating management is furnished with a confidential report of the results of the Bureau's inspections , with recommendations for elimination of the hazards found . These mine - safety inspections include a study of mining practices , conditions , and equipment and in some cases the sampling and analysis of mine air and coal dust . The Bureau of Mines has no regulatory powers , therefore the recommendations made in these reports are merely suggestions , and operators are not required to adopt them . Mine inspections are a check on safety standards , methods , and practices and are essential to any accident -prevention program . A foreman or superintendent may be sincere in his efforts to operate a mine safely and believe that he has done everything possible to attain this end . However , experience has shown that because of his familiarity with the mine and the consequent " nearness " of its various features many unsafe conditions may be , and in most cases are , overlooked ; an inspector , particularly an outsider who is trained to look for hazards , can point out the unsafe conditions overlooked by the foreman or superintendent . Some companies employ safety engineers who make regular inspections of their mines , report substandard conditions and hazards found , and make recommendations for correcting them . Unless these recommendations are carried out the inspections have little value . In making recommendations , due consideration should be given to the feasibility of carrying them out ; the management may and very often does consider a recommendation impracticable because of the

Mar 1, 1935

By G. A. Savanick

The Bureau of Mines has designed, fabricated, and field tested a water jet cutting device capable of perforating nonmetallic well casings for the purpose of completing or stimulating in situ uranium leaching wells. The device is lowered into the wellbore, where it issues a high-velocity water jet that penetrates either a polyvinyl chloride or fiberglass casing, cement, and from 1 to 4 feet into the surrounding uraniferous sandstone. The resulting perforations allow leaching solution to pass between the sandstone and the wellbore. This report describes the water jet perforator, tells how it is used, presents cost data, and discusses the results of laboratory and field tests. The tests were designed to (1) determine the optimum operating conditions for water jet perforation, (2) assess the effects of changes in these conditions, (3) evaluate the performance of the water jet perforator under actual conditions, and (4) compare this method with other methods of well completion. These tests showed that water jet perforation is superior to conventional well completion methods for selectively achieving communication between the well-bore and adjacent sand while maintaining sand control, for restoring permeability lost through wellbore damage, for stimulating poorly performing wells for completing wells with casings that have inside diameters as small as 2 inches, and for extending the effective well diameter.

Jan 1, 1981

By H. C. Miller

For nearly a score of years the American petroleum industry has faced the problem of maintaining its economic structure while oil -producing potentialities greatly exceeded the increasing market demand for oil and its products . However , the combination of maximum civilian demand with rising defense requirements caused an all - time peak in crudeoil production in the latter half of 1941 , with a daily production (as estimated by the Bureau of Mines ) of 4,139,000 barrels in December - an increase of 16 percent over the daily production of 3,573,000 barrels in December 1940. In the event of a long war , a continuing , steady, and adequate supply of petroleum and its products for military and required civilian needs is essential, and the efficiency of recovery of oil from natural underground reservoirs will have to be maximum. Whereas it may not be possible to increase production in some fields , the output from others may have to be drawn at a much faster rate than formerly . More than 10 years ' experience in operating oil fields under proration control has demonstrated to petroleum engineers that some of the efficiency of recovery of oil from reservoir sands and rocks is sacrificed if the oil and gas are withdrawn at too . rapid a rate . As petroleum is an irreplaceable natural resource for which suitable substitutes probably will not be available in desired quantities for many years , any producing method that jeopardizes the quantity of oil that may be recovered from underground reservoirs must be considered at this time of declared war against aggressor nations as conflicting with the best interests of national defense . At best, the efficient recovery of oil is a complex problem . It involves not only a knowledge and application of the fundamentals of fluid flow through porous mediums, but the sources of energy responsible for the movement of oil and gas through reservoir sands and porous rocks to wells must be known to determine the best practices for extracting these hydrocarbons . Reservoir energy is of two kinds - (1 ) water under hydrostatic head underlying the oil in the extraneous parts of the reservoir system and ( 2 ) natural gas under pressure as "free " gas in the reservoir or in solution in the oil . Inasmuch as the efficiency of oil recovery depends largely on the manner in which reservoir energy is used to move oil through reservoir sands and porous rocks to wells , optimum practices for withdrawing the oil cannot be determined until it has been established that the oil in the reservoirs is being forced to wells by an internal gas expansion, by a natural water drive , or by a combination of gas expansion and water drive . There is a fundamental difference in the performance characteristics of gas - expansion and water - drive reservoirs . In a strictly gas - expansion reservoir the energy available to move oil and gas through the porous formations to wells results solely from gas pressure , which is maximum when the reservoir is tapped by the first well . Pressures decline as oil and gas are withdrawn ; consequently, the energy available for moving oil and gas through the oil - bearing formations to wells decreases with production . Curtailing the oil - production rate or shutting in gas - expansion reservoirs entirely will not act to replenish energy previously used in the production of oil and gas ; in their operation , therefore , it is especially important not to waste reservoir energy - the production of oil with high gas : oil ratios will be reflected in lower ultimate recoveries of oil .

Apr 1, 1942

By Walter E. Lewis

This circular presents the method of making tests and apparent results of comparing performance of tungsten carbide insert bits and steel detachable bits by the Cleveland-Cliffs Iron Co. at the company's mines on the Marquette iron range of Michigan. The mines are at Ishpeming and Negaunee, Mich., and include the Cliffs Chaft, Mather "A", Cambria-Jackson, and Mather "B". There are four general characteristic types of high-grade iron ore on the Marquette range. B. H. Boyum2/ classifies the Cliffs Shaft as "hard-ore" and the Cambria-Jackson and Mather "A" as "soft-ore" types of deposit. Shaft sinking through Jasper, slate, and graywacke was in progress at this writing at the Mather "B", with completion at 3,100-foot depth in August 1949. The many different kinds of rock and ore at the mines of the Cleveland- Cliffs Iron Co. and the experimental work being carried on with carbide in- sert bits make it possible to compare, generally, the carbide insert and steel detachable bit. The type of "hard ore" at the Cliffs Shaft mine re- quired close study of the possible use of the insert tit, and their records are more complete than those of the "soft-ore" mines. History and development of tungsten carbide tips inserted in rock drill bits have been covered by R. W. Adamson, C. H. Vivian, R. C. Sullivan,5/ and others. Tungsten carbide insert rock bits have only recently been introduced to the domestic mining industry. Although unusual performance records are being reported at operations employing the insert bits, the general adaptability of the tool to all rock types and the advantages to be gained by using carbide insert tits remains to be demonstrated. Insert-bit performance is being observed at numerous mines and quarries throughout the United States The several mining operations at the Cleveland-Cliffs Iron Co. at Ishpeming, Mich., is one site where exhaustive comparative tests of insert and conventional steel detachable bits are currently in progress. Results to date are sufficiently impressive to be of general interest to the mining

Mar 1, 1950

By Robert L. Lagace

[Suuple Iheorctrccil models are I'M lllolalcd to cltaraclerl/c medium frequency (MF) radio vase pi opaiation in undcrgiounli room arid pillar coal mines fur the purpose of predleiln the most lavolable operating fIegtucncics,md nr,ixunum communic;IIIoil ranges for pottahIe rldu)s with I top antennas. I or conductul IrCC areas, at hree layer propaeaIion IltodcI wit II a Iiallsmissloil IIIIi- lhlllllIIal'u11 lot the plupa!edti ii unlstallt Iris been dcvcloped ;md verified experimentally. 1 lie mode u1 propaCaUetl lakes Ills form of i parallel plane (0,t)) TIM lransnussu)nhne 1% PC of mode with the electric held vertical and the magnetic held hoti/cntal t itliin a planar coal scam in which the tunnels Can he ignored and which 1s hounded above and below hp richer conductivity rock. 1lie model lilt the data best river the 200 io 1000 kH/ frequency hand and exhibits a rc;;lon of optlnrul1l Pelffelntance, with respect Io maxnluiulg radio Communication range, between 300 and 100 klf/. Maximum cunununlcatrorl ranges are sliongls dependent oil the sigiial alleilliatroil sale, ant) Illelclulc on the electrical conductivltles of the coal seam and surrounding ruck. These ranges v;ny tutu about ,,5 Io 100 nleleis Ill a high Iuss scam such as the Ilelllit No. fl to about .100 to 400 meters in a low loss seam such as the Pittsburgh foil portable intrinsically safe radios. The ieslllls die haled on the comparison oftheorc' and experiment for eleven n n. ill sesen coal seams. V OT ate is dice: a conductor such as a power Cable, is present a model has been developed for the coupling of loop antennas to a low loss Coaxial TEM ti;u?smisslon line mode in which the cable acts as the inner conducl,lr and the rock above and below acts as the outer conductor. The electuc and md' nctic Itelds for till` (node are apprlixitllatcly transverse to the cahlC and fall oil expontially with distance in the transverse plane. The principle of reciprocity is used to simplify the analysis. More expelitnental data arc needed to help resolve discrepancies between the theory and the limited data available to date.]

Jan 1, 1980

By J. B. Cheung

The results of a program to demonstrate the technical feasibility of hydraulic borehole coal mining are presented in this report. The hydraulic borehole method of coal mining involves inserting a hydraulic mining device into a borehole that has been drilled from the surface into the underground coal bed. The borehole mining device issues a jet of water under high pressure, which breaks the coal. These pieces of coal, along with the water, form a slurry, which flows to the base of the borehole where it is pumped to the -surface. Phase I of the program encompassed the design, fabrication and factory-testing of a hydraulic borehole mining device. The program was successfully completed with the field tests being conducted at the Wilkeson-Carbonado Coal Field near Wilkeson, Washington. The technical feasibility of hydraulic borehole coal mining was demonstrated by mining 32 tons of coal at a depth of about 75 ft over a period of 4 hours.

Jan 1, 1976

Antitrust Investigation Dropped. - The Department of Justice announced that it was dropping its 5-year investigation of the aluminum industry. The investigation was over whether the aluminum companies were acting as if they were a shared monopoly. Deep Seabed Mining. - The Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) has established an Office of Ocean Minerals and Energy which will be responsible for implementing the Deep Seabed Nard Minerals and Energy Act and the Ocean Thermal Energy Conversion Act. It will establish licensing and regulatory programs.

Jan 1, 1980

By Launa Mallett, Charles Vaught, Michael J. Bmick

Since 1991 the Pittsburgh Research Center (PRC formerly part of the U. S. Bureau of Mines) has been tapping u valuable resource-researchers have recorded extensive interviews will, 30 individuals who are recognized as experts in the area of mine emergency response. These veterans related stories and observations from events experienced during as many as 47 years of response activities. Overall, the response veterans averaged 29 years of mine emergency response experience and 35 years mining experience. Individuals [ ] interviewed included representatives from mining companies, the UMWA and state and federal government agencies. This information was gathered so dial it could he provided to today's miners and to tomorrow's emergency response personnel. It is hoped the collective wisdom that has been obtained can be used to help train new responders and guide those decisions which mill have to be made on the scenes of future events. During interviews file emergency response experts were asked to discuss lessons they had learned through experience. The interviewers asked them to tell what they had learned that would cause them to handle similar situations differently and to tell about things they saw at past events shat the would warn others not to do in the future. In response the experts discussed a variety of things. Most of their responses, however, touched on some of the same topics including: preparedness, experience people on-site mine rescue teams, and decision making. A summary of their responses provides alt overview of [lie lessons learned on-site at tile largest mine disasters in the country.

By S. A. N. Sheya

The U.S. Bureau of Mines performed batch equilibrium contact experiments to examine the ability of activated coconut-shell carbon to adsorb various metal cyanide complexes. Tests were also conducted to determine the effect these cyanide complex impurities might have on the adsorption of gold by the activated carbon. Metal cyanide species included in the investigation were antimony, arsenic, cadmium, calcium, cobalt, gold, iron, mercury, nickel, silver, thallium, and zinc. Tests were made over a pH range of 6.4 to 12.5. The carbon exhibited a preference for gold adsorption over other metals present in solution. In the absence of gold, the metal cyanide complexes were adsorbed; adsorption generally decreased with increasing pH. However, calcium and thallium adsorptions increased with increasing pH, while arsenic and iron were not adsorbed at any pH.

Jan 1, 1989

By M. Clair Smith

The Sweetwater, Castro, Trinidad, New London, and Hilltop chromite properties are situated within an area 8 miles long and 1 mile wide between San Luis Obispo city and Morro Creek, San Luis Obiso County, Calif. Development work at this group of mines was a part of a long-range project by the Bureau of Mines to develop strategic mineral reserves in the United States in accordance with the Strategic Minerals Act of 1939. The junior author of this report participated in the preliminary examinations made in 1941 of the chromite deposits that later in the same year were the subject of more intensive investigation under the immediate supervision of the senior author. The ore occurs in lenses and kidneys in masses of dunite contained in large poridetite areas. Production has boon in the form of lump ore and concentrates from disseminated ore. Work by the Bureau of Miner included surveying, mapping, trenching, sampling, and assaying. It is summarized separately in the text under the name of each mine investigated. The report gives a brief history of the district, describer the concentrating plant of the Castro Associates, and gives detailed results on sampling and assays at the various proportion.

Jan 1, 1951

By Lee Ann Gardner

This U.S. Bureau of Mines publication presents a case study of the processes used in permitting the Nome Offshore Placer Project, a gold mining project offshore Nome, Alaska which operated from 1985 through 1990. The mining project, developed by Western Gold Exploration and Mining Company, Limited Partnership (WestGold), used the BIMA, which was at the time the largest bucketline mining vessel in the world, to dredge gold from the ocean floor. This case study reviews the permitting process from the regulators' and industry's perspectives, as well as characterizing the efficiencies and inefficiencies associated with this case. The Federal, State and local laws applicable to the Nome Offshore Placer Project are identified, agency jurisdiction and interagency relationships are explored, and the chronology of the permitting process is examined. The regulatory authorities for both environmental monitoring and post-mining monitoring are delineated. Significant milestones affecting the project and required regulatory submittals are also included. The case study of the Nome Offshore Placer Project is detailed with respect to agency involvement and coordination, approaches to permitting from both the regulators' and developer's perspective, environmental issues, and permit stipulations which were unique to the project. The advantages and disadvantages of these topics are discussed.

Jan 1, 1992

By B. E. Blair

"This report presents the physical properties and related geological and petrographic data of some 84 rock types from operating mines, quarries, or blasting research test sites. These fundamental rock data were collected as a quantitative approach to underground mining problems, blasting research, or other related studies; however, the data are equally applicable to any problem wherein rock characteristics are important factors. Stress-strain curves are given where available, and the standardized procedure for determining elastic constants from static tension tests is described. Computed (laboratory) and measured (field) free-medium velocities are compared in those instances where such data are available. A chart is given showing both the optimum and minimum number of test specimens for the various core sizes employed in the Bureau of Mines standardized physical-property tests. Rock-type, geographical, and geological indexes are included to aid the reader in locating physical-property data in this and previously published Bureau of Mines physical-property reports.INTROD'OCTI ONThis report presents the physical properties of 84 rock types tested from 16 different projects (sections 37-52). Two previous physical-property reports 2-3 / (hereinafter referred to as parts I and II) presented data on 160 rock types from 36 different projects (part I, sections 1-25 and part II, sections 26-36).The physical-property data were originally obtained to supplement structural mining problems, seismic studies, or related investigations; however, they should be equally applicable in all fields of studies where the strength, hardness, or other properties of rock are important factors. The properties, determined from laboratory tests performed on diamond-drill core, include the following:"

Jun 1, 1955

By Joseph J. Wallace

1. From the standpoint of known recoverable reserves, the following is the order of importance of the beds: Upper Kittaoning, Lower Kittanning, Upper Freeport, Lower Freeport, Middle Kittaning, Clarion, Pittsburgh, and Redstone. 2. mown measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on 1,800 tons per acre-foot of coal in place, me estimated at 1,859 million short tons as of January 1, 1952. Of this, 1,351 million short tons me in beds 28 inches and more thick. Areas in each bed were omitted from the estimates because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1953

By O. C. Blade

Production of crude petroleum in the Middle East (southwestern Asia) and in South America has increased greatly during recent years and has become a significant factor in the world's production of crude oil. Crude oil from fields in the Middle East increased from 256,164,000 barrels in 1946 to 305,833,000 barrels in 1947 and 417,201,000 barrels in 1948. Production from South American fields increased from 446,417,000 barrels in 1946 to 518,652,000 barrels in 1947 and 574,837,000 barrels in 1948. Crude-oil production from Canadian fields increased from 7,726,876 barrels in 1947 to 12,370,875 barrels in 1948, most of the increase being attributable to two fields, Leduc and Redwater, both represented by analyses in this report. Present indications are that production of crude petroleum from all these regions will continue to increase.

Jan 1, 1950

By C. Q. Cupps, R. F. Zaffarano, J. Fry

Reservoir oil analyses from seven wells in the Greater Clareton area have been included in a study of the original characteristics of oil in the Newcastle sandstone reservoir . These data correlated with areal location of the wells show an increase of saturation pressure in a general north - south or downdip direction . The increase amounts to about 500 psi in more than 17 miles , which corresponds to a depth increase of about 1,600 feet . To facilitate application of the data to engineering analyses , average characteristics are given for arbitrary north and south divisions of the 22 - mile - long producing area . The downdip increase of saturation pressure is taken as evidence of updip diffusion of solution gas from a somewhat higher concentration at the bottom of the reservoir . This effect is opposite to that previously observed in two prominent high- relief reservoirs in the Rocky Mountain area . The increasingly greater saturation pressures southward or downdip in the Greater Clareton area suggest a continuing migration of fluids into the structure .

Jan 1, 1964