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By B. J. Moore

The Bureau of Mines has estimated helium resources of the United States at 727 billion cubic feet as of January 1, 1979. These resources are divided into four categories in decreasing degrees of assurance of their existence: (1) Helium in storage and in measured natural gas reserves, 185 billion cubic feet; (2) helium in indicated natural gas resources, 150 billion cubic feet; (3) helium In hypothetical natural gas resources, 186 billion cubic feet; and (4) helium in speculative natural gas resources that makes up the remaining 206 billion cubic feet. The identified helium reserves, which are made up of that in measured and indicated natural gas categories, are further divided into depleting, non- depleting, and stored classifications. The depleting resources are those that are associated with natural gasfields that are, or will be, produced for the natural gas they contain. All of the helium in undiscovered natural gas resources are included in this classification. These depleting resources comprise 600 billion cubic feet of the total resource base. The nondepleting helium resources are estimted tototal 88 billion cubic feet. There is 39 billion cubic feet of helium in storage in Cliffside gasfield near Amarillo, Tex.

Jan 1, 1980

By William A. Hustrulid

A technical and economic evaluation of the potential for improving mining productivity through the use of underreamers in blastholes, specifically in relation to Minnesota taconite, Arizona surface copper and in situ mining operations is presented. Included are (1) a review of the drilling and blasting practices presently being used, (2) a discussion of current underreamer technology. (3) the presentation of a general economic cost model for underreaming, (4) the application of the model to surface taconite, surface copper and in situ mining, and (5) a summary discussion including required performance specifications, potential overall benefits, and recommendations for further development.

Jan 1, 1977

By H. E. Thomas

[The Bureau of Mines has conducted a field hydraulic fracturing experiment to determine the preferential orientation of induced fractures in oil shale at a depth of about 400 feet in the Green River Basin of Wyoming. The hydraulic fracturing treatment was performed by injecting extremely viscous water-base gel and 8- to 12-mesh sand into the oil shale through straddle packers set in an impermeable section of smooth-walled, 6-1/4-inch-diameter open hole. An impression packer proved that a horizontal fracture, which has an average width of about 1/2 inch at the borehole, was induced. A corehole drilled 100 feet from the fractured well intersected the fracture and confirmed its horizontal orientation. Because a horizontal fracture was successfully initi¬ated, it is inferred that the creation of multiple, closely spaced horizontal fractures may be feasible in Green River Basin oil shale.]

Jan 1, 1972

By C. Lurie

This final report describes the work performed by Gulton Battery Corporation under USBM Contract No. HO-112033, entitled "Research and Development on Lithium-Nickel Fluoride Batteries For Mint Life Support Equipment". The lithium-nickel fluoride couple was chosen For this investigation because of its high theoretical energy density (626 Wh/lb), its ability to operate at ambient temperatures and the fact that it showed promise as a secondary system. The theoretical energy density of the lithium-nickel fluoride couple is ten times greater than that of the widely used lead-acid battery and three times greater than the silver-zinc battery which has the highest theoretical energy density of the commercially available secondary systems. The experimental program first evaluated the cell components individually. The results of these studies then formed the basis for investigations of cell performance using experimental three-plate cells. These cells consisted of one nickel-fluoride and two lithium electrodes. All work was performed in a glove box under an argon atmosphere which was sufficiently pure to maintain the shiny appearance on freshly prepared lithium surfaces. The major portion of the work effort was concerned with the nickel fluoride electrode. Binder, conductive diluent, fabrication technique, as well as the nickel fluoride active material itself, were considered. Criteria for binder materials were established and six classes of materials encompassing thirteen binders were evaluated. The candidate materials were initially screened for appropriate chemical and physical properties and finally evaluated in three.-plate cells, Two epoxy powders emerged as the most promising binders. Two types of conductive diluent were evaluated. The first is a carbon black of low bulk density and high surface area. This material is a good conductive diluent; however, electrodes fabricated with it lacked good mechanical strength. It was hypothesized that a uni¬form, small particle size, low specific surface area would improve the mechanical properties of the electrodes. Therefore, two samples of graphicic materials, milled to uniform powders in the one-to-ten micron range were evaluated. Electrodes prepared with the graphitic materials had superior mechanical properties, However, their electrical performance was significantly poorer and voltage losses of 0.2 to 0.3 volts were observed. Several electrolyte solutions were evaluated. N-Methyl-2-Pyrrolidone was tested but found to be incompatible in the presence of lithium. Lithium perchlorate, lithium hexafluoroarsenate, and lithium bromide were tested as two-component electrolytes in propylene carbonate solvent and their performance compared with that of the single electrolyte solutions, Lithium perchlorate gave the best performance. Lithium hexafluoroarsenate was also evaluated in methyl formate and appears to give equivalent performance. The lithium perchlorate-propylene carbonate system is preferred as it is easier to handle and less expensive.

Jan 1, 1973

By S. W. Zoldok

"ERRATUMFor paragraph 1, page 1, read the following:The Cle Elum nickeliferous iron deposits occur on an unconformable contact between the serpentine and overlying Swauk sandstone formation and extend about 2 miles along the Cle Elum River in Kittitas County, Wash.The linear extent of the deposits and their proximity to a large source of,electric power and coal supply indicated that a development program was in order to determine the probable grade, extent of the ore bodies, and a suitable metallurgical process for recovering the iron, nickel, and chromium from the ore.The northern portion of the serpentine formation was investigated by the Bureau of Mines from August to December 1943 and from August to October 1944. The investigation consisted of road building, diamond drilling, sampling, and metallurgical tests.The Geological Survey assisted with logging of cores and made geologic and topographic maps."

Feb 1, 1948

By H. C. Fuller

This paper discusses 105 production runs at Boulder City, Nev., in which titanium metal was made in 200-pound batches. It describes the equipment and techniques used in preparing raw material, the reduction process, and the removal of the reaction mass from the reaction vessel. Also, some data on man-hour requirements are presented. The main emphasis was on producing ductile-grade titanium and developing a standard procedure for obtaining a consistently pure product. Some departures from techniques used before were found to be desirable. The most important of these was the use of a sealed room with a controlled dry atmosphere in which the reaction vessel was opened and the reaction mass removed. This minimized the moisture taken up by the magnesium chloride in the reaction mass, and it could be purified successfully by vacuum distillation. Using the dry room also made it possible to leave al-inch shell of the reaction material on the walls of the vessel, which lowered the iron contamination and eliminated the labor and time-consuming job of cleaning the vessel after each reduction. Another change was lowering of the temperature during reduction to 750° C. instead of 850° C. This was found to give good results more consistently. The first poke to break the crust during reduction was eliminated, as it was found to be unnecessary and only added more work and was another possible way of introducing air. A rotating feed arm was installed in the reaction vessel to distribute the titanium tetrachloride over a larger area and, thus, prevent local overheating. The process, conducted in a batchwise manner as described and followed by good purification and fusion, produces a metal adequate in quality for nearly all purposes.

Jan 1, 1952

By R. H. Hiltz

One of the major hazards in underground coal mining is fire. The inherent hazard of fire is exaggerated by the nature of coal mining restricted areas, the highly combustible nature of coal itself, and a potential for explosive concentrations or dust and gas in the air it becomes imperative therefore to make every effort to eliminate the causes of fires, while providing the most effective means possible to control and extinguish those fires which may occur it has been demonstrated by prior work that the problem of control increases in proportion to the time necessary to institute control procedures. There are several areas of underground coal mining with obvious fire potential. Some of these, like belt heads, have reliantly undergone improvements in standby fire control devices Others, although having fire suppression systems available to them, have not received as complete a systematic study of their problems. Face machinery, particularly those without a water supply, falls in this latter category.

Jan 1, 1973

Provide long-term measurement of mine sidewall closure in backfilled stapes subject to flooding. Approach A water resistant extensometer is made by enclosing a rod-actuated transducer in a telescoping tube which is enclosed within an oil-filled outer housing. How It Works To assemble a water resistant extensometer, a cylinder -shaped transducer and two support rings are pushed into the small-diameter section of the telescoping tube where the transducer is held in place by friction. The outside of the small-diameter section of the telescoping tube is then greased and slid into the slightly larger-diameter section. See drawing. The cylinder-shaped transducer contains a potentiometer whose actuating arm is attached to a stainless steel extension rod that passes through one end of the telescoping tube. A similar rod is attached to the opposite end of the transducer body, and extends through the other end of the telescoping tube. A coil spring inside the large diameter end of the telescoping tube extends the tube

Jan 1, 1978

By Luis v. Coppa

Since its inception in 1910, the Bureau of Mines has been the principal Federal agency involved in ore reserve estimations, using such traditional methods as polygons of influence and variations of inverse distance weighting While adequate for estimating the average are grades in a mining block or section, these methods do mot, however, provide a consistent way of quantifying the reliability of the estimates. This report describes a technique for enhancing ore reserve estimations using geostatistics, the methodology of which combines the spatial and random aspects of geologic phenomena into a formal theoretical framework for deriving the estimation variance of ore reserves. Correctly used, geostatistics enables confidence intervals to be placed around ore reserve estimates calculated from drill hole data. A geostatistical software system was obtained -From the U.S. Geological Survey and installed, aster slight modifications, on the Bureau's Wang computer. System testing and validation was conducted using a simple cast-book-type example. This was then followed by variogram analysis, point kriging and block kriging of data from a previously worked section of a uranium mine.

Jan 1, 1984

By Scott Turner

The present rapid growth of coal stripping in the United States is a curious reversal of the tendency of mining to proceed from outcrop to depth. A combination of technical and economic factors bas stimulated the use of stripping methods until today many million tons of coal We being recovered by open cuts from sites that an earlier generation of engineers would have passed by as not commercially mineable or, if workable at all, only by underground methods. The total quantity of bituminous coal and lignite mined in the United States by stripping in 1928, the latest year for which detailed figures are available, was 19,789,000 short tons. Of this, 71,000 tons came from small workings not equipped with power shovels and 587,000 tons from properties in which stripping and underground work were carried on at the same mine; but as neither of these types is representative of modern stripping practice, they will be omitted in the discussion that follows. The total from strip pits proper in 1928 was 19,131,000 tons, produced by 176 pits employing 385 steam or electric shovels.3 Figures by States are given in Table 1. Detailed statistics will be found in Economics of Strip Coal Mining; a study by O. E. Kiessling, to be published by the United States Bureau of Mines.

Jan 1, 1930

By G. W. Jones

During the course of an investigation by the Bureau of Mines into the causes, behavior, end control of anthracite-line fires, it was observed that the carbon monoxide disappeared from a scaled fire area much more rapidly than could be explained oil the basis of leakage of gases. Two suggestions were offered for this high rate of disappearance; (1) That the carbon monoxide was oxidized at temperatures below 150° C, by either the anthracite or its ash (tests on many anthracites have shown that at temperatures above 150° C carbon monoxide is liberated in the oxidation products when air is passed through it); (2) that the carbon monoxide was oxidized by micro-organisms present in the sealed area.

Jan 1, 1939

By Edward L. McHugh

In 1986, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 5-acre Zwagg Island Wilderness Study Area (OR-12-14) in order to evaluate its identified mineral resources. The study area is located in Curry County, OR, immediately west of Brookings. There is no evidence of mining activity on or near Zwagg Island, and no mineral resources were identified. The steep-sided, flat-topped island is normally accessible from the mainland by way of a sandy beach. The island consists mainly of marine sandstone, mudstone, and conglomerate of the Jurassic Dothan Formation. Dothan Formation sandstone has been used locally as construction material. Rock along the coast has also been used for construction of jetties to improve harbor access; additional work has been proposed at the port of Brookings. Although suitable for other construction uses, stone from Zwagg Island would probably not meet physical requirements for jetty stone. Development of a stone resource on the island is unlikely.

Jan 1, 1987

By Fredrick L. Johnson

The Bureau of Mines, under Congressional mandate, conducted a mineral survey on the Park Range WSA (Wilderness Study Area) in 1984 and 1985. The WSA, located about midway between Tonopah and Ely, encompasses 47,268 acres. No mineral resources were delineated, nor were workings found, during the investigation. There has been, however, exploration in and near the north end of the study area. ASARCO is actively exploring a block of 41 claims for hot-spring type, low-grade, large-tonnage gold deposits. Their claim block is almost entirely in the study area. The Morey mining district, 7 miles southwest of the study area, produced silver and lesser amounts of gold and lead sporadically from the mid-1860's through the mid-1960's. The WSA is underlain by Tertiary rhyolitic and latitic volcanic rocks and by Paleozoic sedimentary rocks. The Paleozoic rocks have been faulted, silicified, brecciated, and hydrothermally altered, and have anomalous concentrations of precious metals and pathfinder elements. Additional exploration in the north part of the Park Range WSA may lead to delineation of gold resources.

Jan 1, 1986

By Richard S. Gaps

In 1983 the U.S. Bureau of Mines conducted a mineral survey of the Golden Valley Wilderness Study Area (WSA), CDCA-170. The 29,887 acre WSA, located in the western Mojave Desert near Ridgecrest, California, is underlain by pre-Tertiary plutonic rocks and volcanic and sedimentary rocks ranging in age from Miocene (?) or Lower Pliocene (?) through Pleistocene and Recent. No mines were operating in the WSA in 1983, nor is any mineral production known to have come from the WSA. Two mining claim blocks, portions of which are within the WSA, and seven isolated prospects, four inside the USA, were examined and sampled. No mineral resources were identified. Widespread propylitic alteration, with localized argillic and alunitic alteration, occurs along the southern boundary of the study area. Samples from claims and prospects within the altered zones are anomalous in gold, silver and arsenic, and some contain antimony, tungsten and mercury, indicating gold resources may exist. Alluvial sample results suggest recent claims in the northwest corner of the study area may also have gold resources. Portions of the study area are within the Randsburg Known Geothermal Resource Area while other segments are considered prospectively valuable for oil and gas and for sodium.

Jan 1, 1985

By Robert G. Lundquist

The Bureau of Mines compared longitudinal strain energy output of a percussive drill to energy determined by measuring maximum piston velocity. Strain gages were used to determine the strain-time waveform and its amplitude at seven levels of operating pressure and eight levels of thrust. The longitudinal strain energy was found to be approximately 14 ft lb less than the maximum piston energy at comparable operating conditions.

Jan 1, 1969

By J. W. Thompson

A contract stipUlating for the delivery of quantities of phosphate rock" f. o. b. mines," and stipUlating that" while this contract is in form an absolute sale for a fixed quantity in each year, it is mutually understood and agreed that the purchase is for the buyer's consumption and not for a sale; the buyer agreeing to give to seller the refusal of any surplus over and above the actual consumption. Buyer is at liberty to increase or diminish the quantity called for in any year, to the extent of not exceeding 10 per cent; provided that the quantity to be taken shall not be less than buyer's consumption; provided further that notice of such increased or diminished demand be given seller 12 months in advance of such change," is to be construed as a contract for the sale of stated quantities of rock, deliverable in approximately equal quantities during each year for the specified series of years, subject only to be increased or diminished after specified notice in any year, where the amount taken would not be les<; than the buyer's consumption, not exceeding 10 per cent, and the contract indicating that the rock was intended by both parties for consumption in the fertilizer plant of the buyer. but the quantity to be taken was not limited by the necessities of' the plant.

Jan 1, 1916

To improve communications between mine workings and surface locations during emergency situations and for administrative purposes. The Approach: Development of a device for interconnecting phone systems which permits two-way communication between a public telephone and a mine pagerphone by authorized personnel. How It Works: The system, developed by personnel at the Bureau&apos;s Pittsburgh (Pa.) Mining and Safety Research Center, makes connections between the public phone line and mine pagerphone line. As shown in Fig. 1., incoming calls are sensed by the ring detector (4) and the system "answers" the call electronically. To reach the pagerphone system, the caller inserts an audible tone of fixed frequency through the microphone of his telephone. This tone is produced by a miniature, pocket-carried tone generator and is detected by a tone recognition circuit (5). When this hap-pens, relay, switching, and logic circuitry (6) closes the connections between the two phone systems. Simultaneously, a page activator (9) places a DC paging voltage on the mine phone line.

Jan 1, 1974

By J. H. East, D. Harrington

"INTRODUCTION The tremendous expansion of industry during the war and the unprecedented demands for metals and minerals are reflected in the production and use of explosives during that period. The increased use of explosives brought added safety problems to industry because of the necessity of using men as blasters who were not entirely familiar with and some who were totally unfamiliar with the characteristics of some or all of the various explosives. A discussion of the characteristics of the ordinary types of explosives used in: industry should assist in giving a better understanding of the hazards attending their use. Explosives are compounded so they may be used with reasonable safety provided the user understands and follows the procedure recognized as standard safety practice. Short cuts and the failure to understand and use recognized safe practices, as well as the selection of explosives unstited for the work at hand, are all part of the safety problem,The extent to which explosives are used in the United States is shown by a study of the statistics compiled by the Bureau of Mines 4/ regarding them. Some of these statistics are shown below and serve as an indicator of the tremendous number of men engaged in the transportation, storage, and use of explosives. Theme men are exposed to the inherent hazards attending this occupation and they should be familiar with the recognized safe practices relative to explosives."

Sep 1, 1946

By A. J. Farstad

The principle objective of the research effort described herein was to identify as rapidly as possible a practical trapped miner location system. Much effort has been expended in the past on the development of a highly sophisticated seismic location system [1] for trapped miners. Field tests of this system have shown that the location accuracy is limited by a combination of seismic velocity anomalies, timing errors, and in general by the relatively weak nature of the signals received at the surface. It was first felt that similar propagation anomalies would be experienced by electromagnetic systems, but to a greater extent than the seismic. However, preliminary tests performed by Westinghouse on the Operations and Maintenance Program, Contract No. H0210063 in 1971 and 1972, indicated that an electromagnetic solution to the location problem may be more feasible than a seismic solution. Thus a more concentrated effort was launched in 1972 and 1973 to more completely determine the feasibility of electromagnetic location systems for trapped miners. Two different approaches to the location problem were undertaken on this program: (1) A pulsed electromagnetic system was developed by the Special Systems Division of Westinghouse in Baltimore, and (2) a Continuous Wave (CW) System was developed by Westinghouse Georesearch Laboratory (WGL) in Boulder, Colorado. Part I of this report will deal only with the development and results of CW Location System developed by WGL. The CW Location System was field tested at three eastern coal mines and at one western hardrock mine. The maximum overburden depth penetrated during these tests was 990 feet at the Robena No. 4 mine near Waynesburg, Pennsylvania. The earth conductivity at this mine was measured to be 1. 1X102 mhos/m, which combined with the deep overburden make this mine representative of expected worst case conditions for a coal mine EM location exercise.

Jan 1, 1973

By T. R. Achenbach

1. This, the final report to the U. S. Bureau of Mines on the program with the subject title, presents the data obtained from June 29, 1973, to April 20, 1974. 2. Operating in the Illinois #6 coal seam, the effectiveness of foam opposed to water was compared in reducing respirable coal dust. A combination of 39 foam generators and 14 water sprays were used during the foam tests. Sixty one water sprays were operated during the water tests. Data from 24 shifts using foam and 21 shifts using water are presented. 3. Additional work on foam generator design should be undertaken to provide coverage to a wider area with foam. 4. The general attitude of those working on the foam program and with the miner at the face was positive. It is urged that the work be continued. 5. The minor respiratory irritations evidently caused by an aerosol effect of the surfactant should be investigated. 6. The statistical analysis of the tests will be made and reported by the U. S. Bureau of Mines.

Jan 1, 1974