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This paper describes the sinking and lining of a 14 foot 6 inch finished diameter shaft down to and into the salt of a typical dome of the Gulf States region. The conditions and nature of the strata encountered divide the work into three distinct sections - that in (1) alluvial surface deposits, sunk through by open caisson methods, (2) water bearing rock, directly above the salt, and in (3) salt. ACKNOWLEDGMENT The writer wishes to acknowledge the cooperation of the sinking contractors, The Dravo Contracting Co. of Pittsburgh, Pa., through E. T. Gott, vice-president, in furnishing the data used in this paper.

Jan 1, 1932

By Loren R. Anderson

This Volume documents the use of the Cone Penetrometer data analysis computer programs VERT and HORZ. The programs are interactive in that they prompt the user for input data and allow correction and modification to be made. The programs read data from the results of cone penetrometer soundings and convert the data to values of tan ø. Mean, standard deviation, skew, kurtosis, linear trends and autocorralation are computed by the programs.

Jan 1, 1982

By James S. Browning

The Bureau of Mines conducted laboratory and small--scale continuous tests of weathered mica pegmatite ores from Hart County, Ga., to determine the technical feasibility of recovering commercial-grade mica concentrates by flotation. Two modifications of the Bureau-developed anionic-cationic method were used. In one method, sodium carbonate and calcium lignin sulfonate were used for pH control and quartz depression; this method yielded mica concentrates containing 98.5 percent mica with a recovery of 91.4 percent. In the other modification, lime and sodium silicate were used with the calcium lignin sulfonate; concentrates containing 98.9 percent mica with a recovery of 86 percent were obtained.

Jan 1, 1966

By W. H. Coghill

Numerous investigators have studied grinding. Each has contributed his bit to a literature that is difficult to correlate. Too many of the results have been transformed into curves with so many "inflection points" and "counterflexures" that they obscure the issue. Some of the investigators have neglected the very essence of the problem, namely the power and the amount of material to which a known amount of work was applied. The purpose of this paper is to show the ease with which results can be interpreted when these quantities are duly recognized. Some grinding tests will be given for illustration. Grinding studies are of two kinds: (1) Study of the character of the ore and (2) study of the performance of the machines. Several ores may be crushed by a given machine, or several machines may be used on a given ore. The illustrations given in this report cover both objectives.

Jan 1, 1934

By T. H. Jeffers

The Bureau of Mines conducted laboratory tests to devise a procedure for extracting copper from low-grade discarded mill tailings. A solid extractant consisting of an organic solvent extraction reagent adsorbed on granular activated carbon was investigated and proved to be satisfactory for extracting copper directly from leach pulps. When this material was used in a cyclic leaching, stripping, and electrowinning pro-cess, 95 pct of the acid-soluble copper was recovered from oxidized mill tailings. The weathered tailings contained 0.24 pct Cu (total) and 0.20 pct acid-soluble Cu. The copper was recovered as cathodes containing, in parts per million, 1.6 Pb, 3.6 Fe, 0.5 Sb, 1.5 AI, 1.9 Mn, and <1 Mg.

Jan 1, 1985

By Theodore Kessler

The purpose of this Bureau of Mines investigation was to determine what new organic compounds or high concentrations of a particular organic species can be formed by exposure of coal derivatives to ultrasonic energy. Tetralin, l-methylnaphthalene, and pyridine were used as model compounds. Gaseous and solid reaction products resulting from the ultrasonic irradiation of these coal derivatives were determined using mass spectrometry. Products from the irradiation of tetralin were studied as a function of time, atmosphere, and sample size. The sonolysis (chemical reactions produced by ultrasonic energy) of tetralin and l-methylnaphthalene produced C2H2, HCN, CH4, H2, CO, and CO2, depending upon the experimental conditions. The ultrasonic irradiation of tetralin also produced diacetylene under certain experimental conditions. The cleavage of organic chemical bonds by ultrasonic cavitation in the absence of water was also observed in this study.

Jan 1, 1967

By Charles H. Atkinson, Robert T. Johansen

Tremendous volumes of petroleum ( crude oil and natural gas ) at present cannot be recovered economically . The feasibility of using nuclear explosions for production stimulation therefore has been investigated . Data from underground nuclear tests conducted by the Atomic Energy Commission were reviewed , and the physical effects were evaluated for stimulating petroleum production . Calculations of the effect on ultimate recovery of increasing reservoir temperature with nuclear explosives showed disappointingly small increases . Production increases caused by fracturing of massive low- permeability reservoirs appear technically and economically promising . Petroleum reservoirs that might be converted from submarginal to commercial production are being located and evaluated as to potential reserves and as a location for a field test .

Jan 1, 1964

By E. D. Gardner

"In recent years efficient safety organizations have been considered essential at all well-managed metal mines. Statistics from numerous mines throughout the country show that the expense of operation of these safety departments is repaid many times by the saving due to fewer accidents. Men trained in first aid, mine rescue and fire-fighting are important parts of the safety organization at most mines. It is more desirable, however, to lay stress ma accident prevention and fire precautions rather than on first aid and fire fighting. Both of these phases of safety work have been well developed in the Globe Miami district. The co-operative mine rescue organization* in this district under Orr Woodburn, is one of the best in the country. Mine rescue teams are kept trained at all the mines and the oxygen breathing apparatus is constantly maintained in good condition. Miners are also trained in first aid, and are offered incentives to make themselves proficient both in mine rescue and first-aid work.The Old Dominion Company is among the leaders in the safety movement in the Globe-Miami district. The safety department at this mine was established January 1, 1914, and has been developed to a high degree of efficiency. W. G. McBride, general manager of the company, takes an active part in the safety work and has given Albert Talon the safety inspector, his active support in developing the organization. The success of the department is dos largely to the ability, tact, and personality of the men directing the work.The following description of the establishment and operation of the safety organization at this mine was prepared from information supplied by Mr. Tallon."

Jun 1, 1921

By Kevin Malone

Chrysotile asbestos occurs in many counties in California, and a small production had been reported at times, but development of deposits had been disappointing. A reconnaissance survey by the Bureau of Mines indicated that several deposits in the serpentine belt in Shasta, Trinity, and Siskiyou Counties might contain enough asbestos of filler grade to supply the growing demand on the west coast. Accordingly from 1956 to 1958 parts of the Mount Eddy and Shasta View deposits were investigated by trenching and diamond drilling to determine their potential. The work comprised construction of roads, bulldozer trenching, excavation of areas for diamond drilling, sampling, and upping. The trenches were excavated to expose the surface extent of some of the asbestos-bearing areas, To determine the downward continuation of asbestos-bearing sections and to secure samples for test purposes, six diamond drill holes, totaling 1,738 linear feet, were drilled in two selected areas. The trenching and core-drilling indicated that the asbestos-bearing material occurs as ribs and lenses of varying thicknesses in a broad belt of serpentine, about 600 feet wide and several miles long,

Jan 1, 1962

By Clayton A. Landsidle

There has been little change in timbering methods in anthracite mines for 75 years, and technical information on strata control is almost wholly lacking. In order to assist the industry to establish technical data, the Bureau of Mines and a Northern field operator are cooperating in underground experiments, the first phase of which has been to investigate pneumatic packing. The four principal methods of packing in mining are hydraulic, pneumatic, mechanical, and hand. The hydraulic pa caring system is believed to have originated at Shenanodah, Pa., in 1864,4/ to prevent destruction of a church by surface subsidence after underground coal mining. This method was used again in 1884 to arrest an underground fire at Buck Ridge colliery, near Shamokin, Pa. In 1901 hydraulic packing was introduced to Europe in Upper Silesia, where it gained in popularity owing to the availability of large quantities of sand suitable for flushing .5/ Hydraulic packing has a number of disadvantages. Chief among these are the softening effect of large quantities of water on the mine floor conducive to heaving action; drainage and punning costs; and the inability to fill roof cavities completely in flat beds.

Jan 1, 1953

By D. Harrington

"There is continued activity in connection with probable reopening of old-time silver producers, but this is largely offset by other obstacles which make metal mining in Colorado a rather precarious proposition. Discussions at the joint meeting of the Colorado chapter of the American Mining Congress and the Colorado Metal Mining Association in Denver, January 20, 21, and 22, brought out many interesting facts, among them that Colorado, once a producer of high-grade ores, and with freight rates, smelting charges, etc. to accommodate high-grade ores, is now compelled to depend almost wholly upon low-grade complex ores or abandon mining, In the face of this, the railroads threaten to advance freight charges, and smelters , because of decreasing tonnage, high labor, etc., must either advance smelting charges or close (the Globe Smelter et Denver recently closed, and it is said that the Salida Smelter will close in February). A serious menace is the possibility of increase of rates by companies supplying electrical power, and the threat of the agricultural interests, now in the saddle in Colorado, to alter the laws so as to greatly increase the burden of taxation to be borne by the mines.In order to stimulate interest in Colorado metal mining, the Colorado Metal Mining Association and Colorado chapter of the American Mining Congress have planned to have an elaborately staged exhibit in the Denver Auditorium during the latter part of the coming summer, This exhibit will reproduce an old time mining camp,including mining structures such as mills, headframes, etc., as well as the camp saloons, dance and gambling halls, etc., together with mineral exhibits from many of the old time mines, no abandoned, but possibly to be reopened. due to increased price of silver, Inasmuch as the Bureau of Mines plans a National First-Aid meet at Denver in August or September, and the Rocky Mountain Mining Institute will also hold its summer meeting in Denver, it seems advisable to hold the three meetings simultaneously and it is proposed to have this done.Labor supply is fairly abundant and apparently not inclined to be dissatisfied; few, if any, strikes or other labor disturbances being found. In some mining regions advances in wages were posted January 1 and no wage reductions are noted.The Rocky Mountain Coal Mining Institute held its meeting at Denver, January 20, 21, and 22, and much attention was devoted to methods of bringing down coal without use of explosives chiefly by undercutting and subsequent use of hydraulic processes of forcing down the coal. Some attention was given the question of labor and it was suggested that the time is at hand when labor unions should be made responsible bodies by incorporation or otherwise. It was agreed to hold the summer meeting in Denver simul-taneously with the holding of the National First-Aid. and Mine Rescue Meet.In general, coal production in Colorado is proceeding satisfactorily with occasional interruption by local strikes, and tonnage is up to that being produced before the strike, but not nearly up to the record of 1918. In general, the labor supply is plentiful, but demand for coal is by no means great and unless some cold weather intervenes, it is probable that the lignite mines will have to go to a three or four day a week basis. There have been no recent disasters, but the Pictou mine of the Colorado Fuel and Iron Company encountered a heavy supply of water, and had to be abandoned until such time as arrangements can be made to pump or bale the water out."

Jan 1, 1920

By I. L. Nichols, K. C. Dean, P. H. Johnson

Hydrochloric acid , sulfuric acid , and chloridizing roast- water leaching methods for dissolution of cesium and rubidium from Maine , Canada , and Southern Rhodesia pollucite ores and their flotation products were investigated by small- scale tests . Optimum conditions were determined to be ( 1 ) for hydrochloric acid leaching , use 12.7 equivalents of 8.8 normal acid per equivalent of cesium in the sample and leach for 6 hours at 100 ° C ; ( 2 ) for sulfuric acid leaching , use 12.7 equivalents of 14.4 normal acid and leach for 2 hours at 120° C ; and (3 ) for chloridizing roast - water leaching , roast minus 200 - mesh ore, limestone , and calcium chloride in a ratio of 2 : 4 : 1 , respectively , for 1 hour at 900 ° C , and leach the calcine for 1 hour at 80 ° C with enough water to give 35 pct solids . Extractions of cesium from ores and flotation products containing over 20 pct cesium were in excess of 97 , 93 , and 96 pct for the hydrochloric acid , sulfuric acid , and chloridizing roast - water leach processes , respectively .

Jan 1, 1964

By Joseph P. Flick, Kathleen M. Kowalski, Lynn L. Rethi, Roberta A. Calhoun

Many miners are involved in tasks at the mine site that are similar to those sub-tasks performed in general construction, maintenance and repair (CMR) type work activities. As a result, many of the injuries in the mining industry today can be traced to employees performing these CMR type work activities. Indeed, a recent analysis of a major aggregate company revealed that 65% of all injuries documented originated from performing such CMR activities. It is hypothesized that the number of injuries to miners performing construction, maintenance and repair (CMR) work activities on mine property may be reduced through improved training that focuses on better hazard recognition using the numerous visual and other cues that are available for evaluating workplace health and safety hazards. To this end, researchers at NIOSH’s Pittsburgh Research Laboratory have merged two proven methods of training miners to recognize hazards, stereoscopic (3-D) slides and the concept of degraded images, into this training program. Stereoscopic (3-D) slides have been shown in earlier NIOSH and U.S. Bureau of Mines research to be an effective training aid for improving the ability of miners to recognize various geologic and mining-induced irregularities that can cause groundfalls.3 They realistically portray the natural mine environment, and thus are an excellent training aid for teaching miners to recognize such visual cues. The degraded image concept, originally developed by the military and used for target detection training, describes scenes where the target is partially hidden by cloud cover, dust, rain, natural barriers, buildings, or other obstructions that can camouflage or confuse the target. Research had shown that flight observers who were trained with less than ideal (or degraded) pictures were more successful in subsequent identification of targets than those trained using ideal (or highlighted) pictures of targets. In order to investigate this concept for training miners to recognize hazards, NIOSH researchers developed a prototype hazard recognition training program using such mining scenes. A control program based on traditional highlighted mining scenes was also developed. Both programs were applied to subjects in a field experiment. Results indicated that miners trained with the degraded images did significantly better on a follow-up test of hazard recognition.4 This hazard recognition program teaches trainees to look for hazards in a more realistic manner than that of the control program. This specific training program for CMR activities involves using the degraded image concept and 3-D slides. The module is designed to educate workers on hazard identification techniques and safe work practices. It focuses on teaching miners techniques for recognizing visual (sight) cues, and then uses these cues to evaluate mining conditions. It should be stressed that other senses, such as sound can also play an important role in hazard detection.

Jan 1, 1999

By Steven R. Munts

In 1985, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied 8,445 acres of the 20,650-acre Tunnison Mountain Wilderness Study Area in order to evaluate its identified mi nerd 1 resources. The study area is located in Lassen County, CA, about 8 miles northeast from Susanville. No mineral resources were identified in the study area based on literature, field observations, and sample results. No mines were operating in or near the study area in 1985, and no mines, prospects, or claims have been located in or within 1 mi le of the study area. The study area is underlain by Pliocene and Pleistocene volcanic units composed of basalt, andesite, rhyolite, and some pyroclastics. No metallic and only nonmetallic commodities are present in the study area. These included stone and sand and gravel. Although substantial volumes of basalt and andesite (stone) occur within the study area, no identified resources of these commodities were delineated. Sand and gravel is not economic because of small occurrence size and lack of local markets.

Jan 1, 1987

By Heinz W. Sternberg

The literature on electrochemical treatment of coal is reviewed, and possible avenues of further research in this field are discussed in this report. Electrolytic reduction of finely distributed coal resulted in the addition of as many as 9 atoms of hydrogen to 100 atoms of carbon. Reduction of coal extracts at controlled potentials indicated the presence of condensed aromatic hydrocarbons and reducible quinones in coal. As much as 65 percent of low-rank coal can be made alkali soluble by electrochemical treatment. Higher rank coals gave smaller yields of alkali-soluble products. However, the nature of this reaction is not clear. The difficulty of reducing coal electrolytically is probably due to the insolubility of coal and not to any structural peculiarity. Reduction of coal by electrolytically generated radical anions appears to be a promising approach for further research.

Jan 1, 1962

By A. W. Deurbrouck

The separations achieved by eight conventional cyclone washers have been evaluated to determine their performance when processing intermediate size coal of 28 mesh bottom size. The dense-medium cyclones provided efficient, sharp separations in treating feeds of up to 44 percent of near-gravity material at separating specific gravities ranging from 1.42 to 1,55 (one separation of a secondary feed was made at 1.63). Complete washability analyses are shown by sizes of the composite feed to these cyclones. The magnetite losses per ton of coal processed ranged from 0.6 to 2.0 pounds; however, of the eight plants reporting losses, seven indicated magnetite losses were 1.1 pounds or less per ton of coal processed.

Jan 1, 1972

By Stephen D. Cramer

The Bureau of Mines conducted a study in which the magnetic fraction of urban refuse was used as melting stock in the preparation of high-strength, low-alloy and carbon steel. Product steels, made from incinerated steel can scrap, nonincinerated-nondetinned steel can scrap, nonincinerated-detinned steel can scrap, and dilutions of these scraps with No. 1 heavy melting scrap, were used in continuing tests in industrial, rural, and marine environments to determine the effect of residual elements and atmospheric pollutants on their atmospheric corrosion resistance. The respective commercial steels were exposed at the same time to establish baseline corrosion data for the test sites. Weight-loss data are reported for atmospheric exposures of 0.5, 1.0, 1.5, and 3.8 years. The marine environment was the most corrosive; the industrial environment was the least corrosive. The atmospheric corrosion resistance of the carbon steel was improved 25 pct by using incinerated scrap and nonin-cinerated-nondetinned scrap in the steelmaking process. In no case was the atmospheric corrosion resistance of carbon steel degraded by using the magnetic fraction of urban refuse as melting stock. The presence of sulfur in the corrosion film was the most important factor affecting the corrosion resistance of the steels. With increasing sulfur concentration, the rate of the corrosion reaction was reduced and the corrosion film became more protective. The residual elements in the product steels most responsible for improving corrosion resistance were copper and tin. These elements tended to increase the concentration of sulfur in the corrosion film. At the levels present in the product steels, Cr, Ni, and Pb had no observable effect on the corrosion resistance of the steels.

Jan 1, 1980

By J. L. Johnson

The U.S. Bureau of Mines investigated the recovery of tin and silver from the Coal Creek deposit in the Talkeetna Mountains, AK. Approximately 5 million st of reserves grading 0.2 pct Sn with silver credits of 0.2 tr oz/st have been delineated by drilling. A 10-to 25-pct Sn gravity concentrate was produced by treating the minus 20-mesh ore with a spiral, then regrinding to minus 65 mesh and tabling. Sulfide contamination in the gravity concentrate was as high as 60 pet. Sulfide flotation of this concentrate produced tailings containing 40 to 50 pet Sn. Overall recovery was 76 pct for tin but only 5 to 10 pct for silver because of losses during sulfide flotation. Other methods tested to clean the concentrate included cassiterite flotation, gangue flotation, nitric acid leaching, and wet and dry magnetic separation. Tin beneficiation tests on the minus 325-mesh fraction included cassiterite flotation, vanning, sulfide flotation, and fuming. The bench-scale and locked-cycle tests were used to estimate the mass flows for a 1,000-st/d plant.

Jan 1, 2010

By T. H. Jeffers

To help maintain an adequate supply of minerals to meet national, economic, and strategic needs, the Bureau of Mines investigated the feasibility of extracting copper from coarse native copper ore with ammoniacal ammonium carbonate solution by a simulated in situ leaching procedure. A 5.9-metric-ton (6.5-ton) sample of minus 30.5-centimeter (12-inch) conglomerate-type ore analyzing 1.96 percent copper was leached in a column for 556 days with a solu-tion that contained, in grams per liter, 2.2 NBs and 1.9 CO[3=]. The copper extraction was 71.4 percent, and reagent consumptions were, in kilograms per metric ton of ore, 1.1 NBs and 0.85 CO[3=] (in pounds per ton of ore, 2.2 NH3 and 1.7 CO[3=]). The pregnant leach solutions contained about 1.4 grams per liter copper, which was readily extracted from these low-tenor liquors with a 1:19 mixture of an organic extractant and kerosine. Copper was stripped from the loaded organic with depleted electrolyte containing 150 grams per liter H2S04, and the copper was recovered by electrowinning with antimonial lead anodes. Conditions also were established for minimal lead transfer to the cathode copper.

Jan 1, 1979

By K. K. Kelley

Despite the wide interest in titanium and its compounds, no heat and free-energy-of-formation values for titanates (that is, compounds formed from titania and other metal oxides) have been available heretofore except for ilmenite (FeTi03). Such data are needed for understanding and developing processes for producing titania and titanium tetrachloride from ores (and possibly slags) and in connection with ceramic usage of titania. This paper reports experimental measurements of the heats of formation at ordinary temperature of 11 titanates-ilmenite, perovskite, barium metatinate, strontium metatitanate, barium-strontium metatitanate, barium orthotitanate, strontium orthotitanate, barium-strontium othotitanate, geikielite, magnesium-titanium spinel, and magnesium dititanate. The experimental method was solution calorimetry. The solution calorimeter was operated at 73.7°C. and used a strong hydrofluoric-hydrochloric acid mixture as the calorimetric fluid and reaction medium.

Jan 1, 1954