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By Peter F. Steidl

As part of the Bureau of Mines methane control program, the Upper Free- port coalbed was studied in Fayette County, Pa., where this coalbed lies about 650 feet below the Pittsburgh coalbed and contains the largest remaining reserves of any coalbed in the county. Coal and overburden isopachs, structure and joint pattern maps, and a fence diagram were prepared using data from gas and oil exploration logs and coal outcrops. These maps will aid in determining the need and/or feasibility of degasifying the Upper Freeport coalbed in the study area. Much of the coalbed in this area is under 600 to 1,400 feet of overburden. By correlation with data from the Pittsburgh coalbed, the gas content at depths of this order is estimated to be between 140 to 300 cf/ton of coal, for a total of 190 to 400 billion cubic feet of methane in this coalbed in Fayette County.

Jan 1, 1977

By R. L. Rough

Photoelastic, wire resistance, and borehole-deformation gages were used to measure the in situ strains when an outcropping Black Hand Sandstone Formation in Hocking State Forest, Hocking County, Ohio, was overcored to stress-relieve the surrounding sandstone. Strains transmitted to the photo-elastic gage did not produce isochromatic patterns suitable for quantitative analysis. Strain readings from the wire resistance gage indicated tensile-strain loading during overcoring; readings from the strain-gage bridges in the borehole-deformation gage indicated compressive-strain relaxation during overcoring. The magnitude and orientation of the computed stress fields obtained from both gages were comparable when the corresponding tensile and compressive elastic moduli were applied. Stresses computed from deformation and resistance gages at depths to 5 feet showed the maximum stresses to range from 1.042 to 2.121 times greater than the minimum stresses. The bearings of principal stresses calculated from the deformation gage readings varied between N 61° E and N 83° E; the wire resistance strain gage bearing computations varied between N 68° E and N 82° E. Measurements of in situ strain in sandstone were shown to have promise but to require further development in field technique that could likely be achieved through experience.

Jan 1, 1971

By Heather N. Dougherty

In the absence of values for each influencing parameter and a known relationship of input-output space, novel approaches should be implemented as proxy solutions to mathematically complicated problems. Proxy solutions can be in the form of linear or non-linear multiple regression equations. Predicting the performance of gob gas ventholes is one of these mathematically complicated problems as it is difficult to know the exact relationships between various parameters influencing gob gas venthole (GGV) performance from active and sealed (completed) longwall panels. In this paper, a discussion of the NIOSH-developed software suite for methane control and prediction (MCP) based on an artificial neural network (ANN) is presented. The application of the ANN-based software suite to develop algebraic relationships for gob gas venthole performance prediction in sealed and active longwall panels is sought. Output information obtained from the NIOSH-MCP software as a response to various input parameters were used to create an input-output database for total flow and methane percentage from GGVs operating in active mines during completed and sealed panel situations. Due to the multi-variable nature of the software, outputs generated using the software for various inputs were used to develop analytical equations first using linear and then second using non-linear multivariable regression techniques. The advantage of this method is its ability to better understand the significant parameters of the relationships between the inputs and outputs for gob gas venthole production in active and sealed panels and to be able to predict their performances using relatively simple analytical functions.

Jan 1, 2010

By Launa G. Mallett, Dana Reinke, Charles Vaught, Michael J. Brnich

As mines become safer and major disasters fewer, the number of experienced emergency responders is decreasing. This decrease will create a gap in response expertise which could have serious ramifications during future mine disasters. While working toward safety goals which may make emergency response obsolete, it would be reckless not to acknowledge that the potential for disaster still exists and that the protection of miners in such circumstances must remain a priority. The Mine Emergency Response Interactive Training Simulation (MERITS) is a computerized mine emergency simulation that meets a variety of needs. It allows personnel in leadership positions to test their knowledge and skill. Groups of individuals composed of representatives from mining companies, labor, and government agencies can practice working together during the simulated mine emergency much in the same way an actual emergency would require. An individual could also run the program to enhance his or her response skills. With this training tool, responders will be able to learn from their mistakes before facing situations with potentially catastrophic consequences. This paper discusses MERITS and its use in providing command center training.

By Oliver Bowles

The mineral asbestos, because of its unique fibrous character, is allied to cotton and wool but has the advantage of heat and fire resistance; therefore, it supplies many industrial needs for which no substitutes are yet available. This report covers the essential features of the asbestos industry, including occurrence, production, mining, milling, utilization, international trade, and marketing. The United States leads all countries in the manufacture of asbestos products, but domestic sources furnish only a small fraction of the raw material required. As the United States is dependent to so great an extent on foreign supplies of raw materials, the bulletin deals at length with the asbestos industry in foreign lands. Several reports now available deal with the industry in individual countries. Among them are Chrysotile Asbestos in Canada, by J. G. Ross; Asbestos in the Union of South Africa, by A. L. Hall; and a series of articles on the Russian industry, by Walter A. Ru Keyser. These have been drawn upon freely, and full acknowledgment is hereby made for the helpful information thus secured. The file of the magazine Asbestos also has furnished many valuable data touching all phases of the industry. Many other books and articles listed in the bibliography at the end of this bulletin have been utilized and have been supplemented by the author's intimate acquaintance with the industry for about 20 years. The intent is to present a concise, world-wide, historical, technical, and economic treatment of the asbestos industry.

Jan 1, 1937

Illumination hardware developed in conjunction with previous Contracts H024202l, H0242049, and H0242023 had not been adequately tested in actual underground work situations. The purpose of this contract was to install and monitor this equipment on mining machines and in actual working places of coal mines to gain experience with the use of the lamps and support equipment in the abusive and critical environments for which they were intended. The equipment that was to be tested consisted of the following: a. Lamps -A variety of sizes of permissible fluorescent lamps which operate from 12 volts DC power. These include the following sizes: Model 8, (9 watts) 2" diameter; Model 15/2 (14 watts) 2" diameter; Model 15/3 (21 watts) 3" diameter; Model 20 (25 watts) 3" diameter; Model 30, (28 watts) 3" diameter; and Model 40, (39 watts) 311 diameter. Representative photographs of these lamps are shown in Figure 1-1 and 1-2.

Jan 1, 1976

By Corale L. Brierley

Beneficiation of phosphate in the southeastern United States generates a slurry of finely divided clay. These clay-wastes are impounded to allow the particulates to settle. The aggregation of phosphatic clay-slime wastes and slimes produced from potash beneficiation by microbial processes was studied using several bacterial species known to produce polymeric substances. Experiments included flocculation capacity of clay-slimes by whole cells, the determination of respiratory activity of whole culls in the presence of phosphatic clays, observation of clay flocculation rates by polymers derived from these organisms, and clarity of polymer-flocculated clay suspensions. The polymer-producing organisms exhibited little capacity for flocculating phosphate and potash clay-slimes. Fungal spores of Cladosporium cladosporioides (isolated from a phosphate clay-waste impoundment), when agitated with clay-slime for several days, caused the clay to form pellets. Separation of the clay/fungal pellets (density 1.1 g ml-1) from the process water might he possible using a screening technique. Studies with C. cladosporioides included the determination of suitable energy substrates and supplements for growth, absorption studies of a pigment produced by the organism, determination of the time required for bioflocculant production by the organism, and an elucidation of the conditions required for the pelletization of clay-slimes by the fungus.

Jan 1, 1982

By C. Travis Anderson

"Nickel is an essential metal in stainless steel, armor plate, and nickel steels and also in nonferrous alleys, such as monel metal and cupre-nickel, which are used in marine service. Nickel is one of the metals that must be greatly restricted in civilian use to provide the amounts needed for our War program. Consequently, it is desirable to investigate every possible substitute.The 5-cent coin no z in use contains 2.3 percent nickel. At the end of 1941, about 450 tons of nickel was being consumed annually to produce these coins. If the nickel used for that purpose in 9141 had been diverted to military use, 15,000 tons of armor plate could have been produced. As nickel is vitally needed for military as well as essential civilian products, it would seem desirable to substitute some other alloy for the 25 percent nickel alloy now being used. The Bureau of Mines has been asked to suggest possible substitutes.The substitute should have physical properties similar to the alloy now being used. It should have a metallic appearance and ring and a reasonably white color, so to be distinguishable from the present 1-cent coin. It should also be reasonably resistant to corrosion."

Aug 1, 1942

By J. R. Nettle

The development of a process for upgrading offgrade titanium metal by electrorefining in molten salt led to an investigation of the electrotransfer characteristics of selected metals when alloyed with the titanium to be refined. Previous tests on seven binary titanium alloys showed that the degree of transfer of the alloying constituent depends on the constituent and on the operating procedurese.5 This report describes tests on electrorefining ternary mixtures of titanium with selected metallic elements. Ten alloys were prepared from high purity titanium and 2-1/2 percent of each of the metal pairs selected from the same elements used in the binary study; manganese, vanadium, chromium, zirconium, tin, molybdenum, aluminum. Operating variables were similar to those investigated in the binary alloy study that gave minimum alloy metal transfer. The data presented indicate the transfer characteristics of the various metals and combinations tested relative to each other.

Jan 1, 1962

By Forest J. Sur

"INTRODUCTION This report describes an exploratory project conducted by the Bureaus of Mines on a fluorite deposit, near Glenwood, N. Mex. Results of wagon drilling, crosscutting, and test pitting are given, together with results of metallurgical tests made upon samples of the ore. Mining and treatment methods are suggested.C. H. Johnson, Bureau of Mines engineer, examined the deposit in August 1942. H. E. Rothrock, of the Federal Geological Survey, completed a preliminary geologic study and mapped the deposit during the fall of 1942. As a result of these brief investigations, it was concluded that the deposit contained substantial inferred ore reserves, and exploratory work was recommended. G. A. ApelI, also of the Bureau of Mines, made a topographic and underground survey and report on the mine in March and April 1944. A wagon drill, air compressor, and other equipment and supplies were delivered to the property on May 19 to 23, 1944. Drilling began under the direction of the author on May 25, 1944, and was completed in October 1944. The results of drilling and. sampling form the basis of this report."

Apr 1, 1947

By P. J. Watson

The objective of this study was to prioritize the potential risks nuisance and biologically active dusts and fumes present in metal and nonmetal mines. This was accomplished by ranking numerical values derived from a matrix formula calculation that took into account dose, mine population, and sampling size. Data used in these calculations were obtained from the Mine Inspection Data Analysis System (MIDAS). The dusts determined to have the highest risk potential were quartz respirable particulates, mine dust, cristobalite respirable particulates, welding fume components, and nuisance respirable dust. Other dusts and fumes that were not ranked in this study, due to small sampling population, but which show a potential risk, include asbestos, talc, hydrogen cyanide, organic compound dusts, arsenic, metal dusts, and metal and nonmetal fumes.

Jan 1, 1987

By G. W. Jones

The results presented in this report deal with the elimination of explosion hazards of ether-oxygen mixtures by the addition of helium. The method is based upon the fact that every combustible gas, vapor, or dust will not burn or explode when the oxygen content of the mixture is reduced below certain definite values. These critical oxygen values are usually different for each combustible, varying with the percentage of the combustible present in the mixture and also with the inert gaseous material used to reduce the oxygen content of the mixture.

Jan 1, 1941

By Jerry E. Olson

In 1984, the U.S. Bureau of Mines conducted a mineral survey of the Pahute Peak Wilderness Study Area (WSA) (NV-020-621), which covers 57,529 acres in Humboldt County, NV. About 90 percent of the WSA is underlain by Tertiary volcanic and shallow intrusive rocks. Of the remainder, metasedimentary rocks of unknown age are in contact with Cretaceous intrusive rocks in the northwest corner of the WSA. The entire WSA is within an upthrown fault block of the Basin and Range physiographic province. Portions of the WSA, especially south of Pahute Peak (Big Mountain), may be part of an eroded caldera structure. No mines or evidence of major exploration were identified within the WSA. Workings in Copper Canyon, claim blocks along the northwest boundary, and zones of anomalous character as defined by the Bureau of Land Management were examined. No mineral resources were identified, but sample results indicate three significantly mineralized sites, one with indications for zinc skarns in Copppr Canyon, another favorable for precious metals 2 miles south of Copper Canyon, and another area near the northwest boundary with geologic conditions characteristic of molybdenum deposits. Further investigation of these sites is warranted. Petrified wood is present in small amounts near the west central range front.

Jan 1, 1986

By Terry J. Close

From 1981-84, Bureau of Mines personnel examined and evaluated mines and prospects in the highly mineralized 62,400 acre Inyo Mountains U. S. Bureau of Land Management (BLM) Wilderness Study Area (WSA), located east of Lone Pine, CA. The 62,400 acres studied is the part of the 87,145 acre WSA designated as suitable prior to February 28, 1983. The WSA is underlain principally by quartz monzonite and quartz diorite that have intruded sedimentary and volcanic rocks. Three types of mineral deposits are present: 1) gold in fissure veins, 2) silver in fissure and replacement veins, and 3) talc in metasomatic lenses. Of the 84 nines, mills, and prospects examined, 54 are significant: 1) 5 in the intrusive rocks total about 4.4 million tons of inferred marginal gold reserves averaging 0.24 oz gold and 0.74 oz silver/ton; 2) three associated with intrusive-sedimentary rock contact zones total about 280,000 tons of inferred subeconomic silver resources averaging 7 oz silver/ton; 3) 27 gold and silver occurrences in the intrusive and sedimentary rocks total about 1.2 million tons of material in poorly defined bodies too small or low grade to be resources; 4) 15 gold and silver occurrences in the intrusive and sedimentary rocks are too poorly exposed to estimate tonnage and grade; and 5) four talc deposits along intrusive-sedimentary contact zones have inferred marginal reserves totaling about 640,000 tons. The marginal gold reserves at $450/oz might be profitably mined (reserve) at a gold price of about $600/oz and the subeconomic silver resources at a silver price in excess of about $27/oz. The marginal talc reserves might become minable at prices of about $50/ton and $80/ton for unprocessed and processed talc, respectively, after present supply sources are depleted. At most of the 54 significant mines and prospects, additional reserves or resources would likely be disclosed by trenching or drilling. Present in the WSA are 13 gold mills, numerous small pits and cuts, 270 underground workings totaling about 36,000 ft, and 80 mining benches totaling about 11,000 ft. Gold, silver, or talc were produced from most of the workings. A total of 1,561 lode and 18 placer samples were taken.

Jan 1, 1985

By Charles K. Rose

The Cebolla Creek titaniferous iron deposits near Powderhorn in southern Gunnison County, Colo., were examined by the Federal Bureau of Mines as part of an overall program to investigate the Nation's titanium and iron resources. The deposits occur around the periphery of the Iron Hill stock, which underlies an area of about 12 square miles. Concentrations of magnetite, ilmenite, and perovskite arc localized along fractures in the pyroxenite stock. Mineralogical studies of composite surface samples collected in 1956 showed that most of the iron is present in ilmenite-bearing magnetite. Perovskite is the chief titanium mineral in the magnetite-rich and augite-rich types, and sphene is the principal titanium mineral in the placer material. The mica-rich rock contains approximately equal amounts of perovskite, ilmenite, and sphene.

Jan 1, 1960

By Rad B. Langston, Ted J. Williams, John A. Marjerison, Rimas T. Pakalnis, Tom M. Brady, Doug C. Bayer, Mark J. Bren

Underhand cut and fill mining methods are used at the Lucky Friday, Stillwater, and Galena mines in the western US in an effort to safely mine in difficult ground conditions and as a primary mining method where access below the ore is limited. The method has evolved at each mine to meet the unique situations associated with their milling procedure and mine layout. Details of the operational aspects of the backfilling and mining cycles at each mine are presented in this paper, accompanied by a summary of the mechanical properties of the backfill and its in-situ geomechanical behavior.

By W. L. Acherman

The Bureau of Mines found the chemical and galvanic corrosion behavior of the TZM and molybdenum-30 tungsten alloys to be generally equal or superior to that of unalloyed molybdenum in many aqueous solutions of acids, bases, and salts. Notable exceptions occurred in 1 [N] nitric acid, where both alloys corroded appreciably faster than molybdenum. In mercuric chloride solutions, the TZM alloy was susceptible to a type of crevice corrosion which was not due to differential aeration. The alloys were usually not adversely affected by con-tact with dissimilar metals in galvanic couple experiments, but the dissimilar metals sometimes corroded galvanically. Both alloys were resistant to substitute ocean water spray at 60° C.

Jan 1, 1968

By Raja V. Ramani

The potential usefulness of reclaimed surface-mined land has received much attention recently. In an effort to develop a procedure for evaluating postmining land use potentials, specific mines in various regions of the U.S. were studied to determine the extent of current mined-land planning and to discover characteristics that are regional in nature. As part of this investigation, the Chinook Mine-West Field, located in western Indiana, has been studied. The Chinook Mine is presently operated by AMAX Coal Company and has been in continuous operation since 1928 under various ownership. The status of current reclamation and land use planning was reviewed. In addition, site planning principles were applied to the active mine area. This application included formation of a data base and development of postmining land use plan alternatives. Key factors affecting site potential realization for midwestern area mines have been identified along with suggestions for applying land use planning processes to mined-land planning.

Jan 1, 1983

By John W. Brown

Electrical resistivity surveys were conducted at three sites in Wyoming in an attempt to detect underground rubble zones in oil shale and to determine their size and resistivity contrast. The zones were detected at Rock Springs sites 4 and 5, but none were detected at Green River site 1. The resistivity of the rubble zones at sites 4 and 5 is greater than that of the surrounding rock. The zones at sites 4 and 5 are concluded to be roughly ovaloid in shape, with a horizontal diameter of 33 m and a vertical thickness of 24 m. Both rubble zones and the blasting that created them are considered to be centered at a depth of 24 m.

Jan 1, 1972

By Kenneth C. Stewart

This contract was directed toward a study of the attenuating properties of earmuffs as worn by miners. Two attenuation measurement procedures were utilized. Human subjects were tested in a diffuse sound field according to threshold shift procedures recommended by the American National Standards Institute and a physical measurement procedure was accomplished in the same diffuse field on the same human subjects with microphones placed simultaneously on the inside and outside of the muffs. All measurements were obtained in one third octave of random noise. The results of the study indicated that physical and psychophysical attenuation measurements are in essential agreement at frequencies from 125 Hz to 2 KHz. Above 2 KHz the psychophysical measurement demonstrates larger amounts of attenuation than the physical measurement. The difference in attenuation ranged from approximately 7.0 dB to 9.0 dB at frequencies of 4 KHz and above. A possible explanation for the observed differences in attenuation has been presented.

Jan 1, 1980