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By W. E. Foreman

A mathematical model was developed to assess the costs for reclamation of surface mining using the shovel overcasting operation, the front end loader operation, and a backfilling operation. A literature review was made of the present laws in Kentucky, Pennsylvania, Virginia, and West Virginia pertaining to surface mining and of the various parameters that influence the input data for a mathematical model. It was determined that the working mathematical model would have to be applied on an area to area basis, preferably on a permit by permit basis in the area where surface mining was being done. To this end, a flexible model was developed with input data obtained from the area of study. The results of the study show that the cost per ton of coal for reclamation can be estimated for various reclamation levels. Validation of the model was done for selected permits from Virginia. It was determined that the permits could easily be used for input data to the model.

Jan 1, 1974

Major activities of the Bureau of Mines Explosives Research Center during fiscal year 1965 (July 1, 1964, to June 30, 1965) are reviewed briefly. Part 1 summarizes significant accomplishments of the projects that were active during the report period. Part 2 presents short abstracts of the publications that appeared in the Bureau series and in other media during fiscal year 1965. Publications issued after June 30, 1965 are noted where pertinent in footnotes but are not abstracted. ACKNOWLEDGMENTS The Bureau of Mines gratefully acknowledges the support given through cooperative agreements by the following organizations to investigations con¬ducted by the Explosives Research Center during fiscal year 1965: Dow Chemical Company Manufacturing Chemists' Association Monsanto Chemical Company The Sulphur Institute

Jan 1, 1966

By J. H. East, R. S. Sanford, W. M. Traver, W. S. Wright

"INTRODUCTION This report describes the results obtained from a diamond-drill exploration project performed by the Bureau of Mines on the nickel deposits of the Yakobi Island, Alaska. The Federal Geological Survey 6/ completed a detailed geologic study and mapped the area during the summer of 1940, and a Bureau of Mines examining engineer 7/ made a preliminary examination of the deposits in June 1941, at which time core drilling was suggested as the logical means of determining the extent and grade of the deposits. Equipment and supplies were unloaded on the beach at Yakobi Island on October 21, 1941. The drills were moved to Bohemia Basin, where actual drilling operations wore begun under the direction of a Bureau of Mines engineer 8/ on November 7, 1941. Two core-drill holes were completed on December 7, 1941. Upon the request of the drilling contractor, operations were recessed owing to severe winter conditions. Work on the project was resumed April 27, 1942, under the direction of another Bureau of Mines engineer 9/ and was completed August 15, 1942. During the 1942 season, 13 core-drill holes were completed, and 10 surface pits and a tunnel were sampled. A total of 5, 191 feet of core-drill hole was drilled in 15 holes during the entire project. The results of drilling and sampling form the basis of this report."

Jan 1, 1948

By Foster Fraas

This report describes the application of pulsed magnetic fields derived from alternating and intermittent magnetizing currents. Application of such pulsed magnetic fields to the matrix-type separator permits (1) the complete discharge of the magnetic fraction with wet feeds and (2) the dry separation at particle sizes down to 325 mesh. At smaller particle s indications are that frequencies above 60 hertz will be required. Applications of intermittent magnetizing current to the cross-belt separator give the cross-belt-separator an advantage over the conventional constant-field cross-belt and induced roll separators; the intermittent current enables the cross-belt separator to separate matted fibrous and magnetically coagulating feeds, a type of feed that occasionally occurs with mineral, industrial, and secondary materials.

Jan 1, 1973

By A. Gene Collins

This report discusses some of the chemistry and geochemistry of cesium and rubidium. Knowledge of the cesium and rubidium content of oilfield waters aids in resolving the origin of waters and petroleum, exploring for petroleum and other valuable minerals, discovering water pollution sources, and augmenting the knowledge of geologic formations. The methods described in this report permit the detection of less than 0.01 mg/l of cesium and/or rubidium in a complex oilfield brine or water. Solvents possessing high-dielectric constants were evaluated for their ability to extract cesium and rubidium tetraphenylboron from oilfield waters and for their flame emission characteristics. Nitroethane was selected and used for the extraction and flame spectrophotometric determinations because it gave the highest sensitivity. Cesium 137 and rubidium 86 were used to determine the extraction efficiencies, which were about 87 percent and 58 percent respectively using a single 10 ml nitroethane extraction from a distilled water matrix. The standard deviation of the determination was 0.0008 mg for cesium and 0.0007 mg for rubidium in the 0.01 mg range.

Jan 1, 1965

By Oren C. Baptist, Carlon S. Land, Eliot J. White

The water sensitivity of the oil - gas - producing sandstones in three fields in the Patrick Draw area of southwestern Wyoming was estimated by laboratory testing . The tests used to estimate sensitivity , which is a measure of the loss of well productivity if the producing formation is invaded by fresh water , are : Porosity ; permeability to gas , water , and brines ; saturation characteristics with air displacing water from the samples and by mercury injection ; and identification of clay minerals by X - ray diffraction . Laboratory results indicate that the degree of water sensitivity of the sands in the Patrick Draw, Table Rock , and Desert Springs fields vary , in that order , from moderately sensitive to highly sensitive . The main cause of the sensitivity appears to be the movement of fine particles in the pores , but the swelling of a small amount of an expandible clay mineral may also contribute to the permeability reduction observed in the samples . Laboratory results further indicate that the permeability of the sands to fresh water is seriously reduced if they are first flushed with sodium chloride brine ; calcium chloride brine is less harmful to the sands than sodium chloride brine . The low original permeability of the oil sand in the Patrick Draw field , together with its moderate sensitivity , indicate that the rate of water injection for the secondary recovery of oil will be low . Limited field experience in two pilot - injection wells confirms this prediction .

Jan 1, 1964

By J. B. Gayle

The Bureau of Mines studied the effects of air oxidation on the recovery of float coal. Both batch-and continuous-type tests were made on six bituminous coals, representing the range in rank of coals now commercially used for carbonization, and on one anthracite coal. The effects on flotation recovery of oxidation at 1000 C for periods up to 50 days were investigated using an alcohol-type frother and a kerosine-pine oil reagent. Two series of release analysis tests were made, using one medium-volatile bituminous coal. Float coal recovery was adversely affected by oxidation in all tests where the alcohol-type frother was used. Conversely, a small degree of oxidation improved recovery with kerosine-pine oil frother for some of the coals in continuous tests. Prolonged oxidation (beyond about 14 days) adversely affected float coal recovery for all coals, the effect being more pronounced for batch-type tests and for tests using alcohol-type frother. Reagent selectivity for the rejection of both ash forming and sulfur bearing minerals was reduced by oxidation. Severe reduction of reagent selectivity required only about 3 days' oxidation for alcohol-type frother but more than 10 days' oxidation when the kerosene-pine oil reagent was used.

Jan 1, 1965

By A. G. Starliper, H. Kenworthy

A procedure was developed for the separation of lead and sulfur in industrial concentrates of galena by a combination of chlorination and fused - salt electrolysis . Galena could not be satisfactorily electrolyzed in the various media tried ; however , when it was treated with chlorine the resulting lead chloride could be effectively separated electrically into lead and chlorine . An apparatus was designed and constructed to chlorinate galena and to volatilize simultaneously most of the chloridized impurities . By electrolyzing the chlorinated concentrate , a high percentage of lead was recovered . Anodic chlorine was drawn from the cell and was used to chlorinate new feed . In many runs , the recovered metal analyzed from 99.8 to 99.9 percent lead . Lead was also distributed as a chloride in the bath , and a small portion was in the volatile fraction produced during the chlorination step . During a tinuous operation , only 0.1 percent of the total lead was discarded ; 99.9 percent was accounted for in the metal , electrolytic bath , and washed or leached chlorination condensate which was essentially lead chloride . About 95 percent of the sulfur from the galena was recovered as a byproduct of over 90 - percent grade .

Jan 1, 1964

By J. W. Sterner

The Bureau of Mines conducted studies on four makes of Japanese automobiles, three 1981 and one 1982 model years, received from three manufacturers to determine if their materials composition would present problems to the current technology used to process junk automobiles for metal recovery. One of each make of automobile was hand-dismantled to determine the materials composition. In addition, two nearly identical automobiles of each make were shredded at a commercial operation where all metal products and rejects were collected for analysis to determine metal and nonmetal distribution. The average weight of the four automobiles to be dismantled, less batteries, tools, and fluids, was 1,938.3 lb. The weight was distributed as 1,472.9 lb. ferrous and 115.6 lb nonferrous metals, 275.2 lb combustibles, 72.3 lb noncombustibles, and 2.3 lb electrical components. The dismantled automobiles, less gas tanks, fluids, tools, wheels, tires, and batteries, which were all removed from the automobiles that were shredded, contained an average of 1,389.1 lb ferrous and 101.6 lb nonferrous metals, 305.7 lb nonmetals, and 2.3 lb electrical components. In comparison, materials collected from the shredded automobiles averaged 1,304 lb ferrous metals, 80 lb nonferrous metals, and 341 lb landfill materials. There were no materials used in the manufacture of the late model Japanese automobiles that should present handling or processing problems to the steelmaking or secondary metal recyclers.

Jan 1, 1984

By L. F. Heising

Ten composite samples of Mesabi Range nonmagnetic taconite from the Hibbing, Minn., area were evaluated by flotation and by reduction roasting-magnetic separation to determine their potential as a future source of iron are. Only one of the composites yielded concentrates that could be considered marketable, using as a criterion a 10-to-1 iron-to-silica ratio. Cursory petrographic examinations of all 10 composited samples and a detailed mineralogical study on 1 sample suggest that unfavorable mineralogical associations between iron and gangue minerals are responsible for their poor beneficiation characteristics.

Jan 1, 1967

By Kenneth H. Johnston

For the past several years, Bureau of Mines petroleum engineers have arranged tours of selected waterflooding projects for the spring meetings of the Kansas-Oklahoma Waterflood Association. These tours are conducted to demonstrate unique operating methods and new field equipment and to provide additional opportunities for exchanging information. Each of these tours has been supplemented by a published report describing in detail the projects visited. This report has been prepared for distribution during the 1960 spring tour of four waterflooding projects in Greenwood County, Kans. (fig. 1). Three of the projects produce oil from the Bartlesville sand, and one produces from the Cattleman sand. The Bartlesville-sand floods have been in operation from 4 to 12 years and have produced about 3,910,000 barrels of waterflood oil from the injection of approximately 64,715,000 barrels of water, a cumulative water-injected to oil-produced ratio of 17 to 1. The Cattleman- sand flood, which has been operating for 3-1/2 years, has produced about 842,000 barrels of waterflood oil from the injection of approximately 9,305,000 barrels of water, a cumulative water-injected to oil-produced ratio of 11 to 1.

Jan 1, 1960

By Forrest T. Moyer

The overall disabling work injury experience, excluding office- workers, at nometal mines and mills during the period 1961-63, as reported to the Bureau of Mines by operators, was 77 fatal and 7,201 nonfatal injuries during an aggregate worktime of 335,029,685 man- hours. These injuries, fatal and nonfatal combined, occurred at a frequency rate of 21.72 per million man-hours, comprising 0.23 for the fatal and 21.49 for the nonfatal injuries. The combined severity rate of the disabilities was 2,312 days lost or charged per million man-hours, consisting of 1,379 for the fatal and 933 of the nonfatal injuries, The average severity of all disabilities during 1961-63, was 106 days per injury, The number of days lost or charged, excluding officeworkers, at nonmetal mines and mills during 1961-63, was 462,000 days charged to fatal injuries and 312,461 days lost from nonfatal injuries. The outstanding causes for fatal injuries were explosions (18 fatalities occurred in a major mine-explosion disaster in a potash mine in Utah in 1963) and falls of rock or ore from back or side, while most nonfatal injuries were caused by handling materials, slips or falls of persons, haulage, and machinery. The parts of the body most frequently injured during the period 1961-63 were the trunk, hand and finger, and foot and toe, An average of 52,810 men were at work daily, There were 20 nonfatal disabling injuries reported for office- workers at nonmetal mines and mills during the period 1961-63 during an aggregate worktime of 23,088,496 man-hours, These injuries occur- red at a frequency rate of 0.87 per million man-hours, There were no fatal injuries reported.

Jan 1, 1967

By D. R. Mathews

The solubility of carbon in electrorefined vanadium was determined to be approximately 0.27 wt pct at the eutectic temperature 1,650° C and 0.03 wt pct at 700° C. The tensile strength and hardness of vanadium increased with car-bon content to the solubility limit, but this effect was small, probably because of the narrow solubility range. Between the solubility limit and 0.3 weight-percent carbon, the second phase had essentially no strengthening effect in vanadium. The second phase, observed metallographically at the grain boundaries and within the grains, was shown by autoradiography to contain high-carbon concentrations. This second phase was identified as VgC by X-ray analysis. The VgC in the grain boundaries contributed largely to the poor cold-and-hot workability of vanadium-carbon alloys. Increased concentrations of V2C occurred at the grain boundaries of the high-carbon alloy ingots as a result of homogenization at 1,600° C for 1 hour. Alloy ingots containing more than 0.36 wt pet carbon (a calculated 2.9 wt pct VaC) following homogenization, cracked severely and failed by intergranular fracture upon swaging at 900° C.

Jan 1, 1965

By Gerrit V. R. Goodman

Future coal mining systems will be able to cut from crosscut to crosscut where advances could exceed 100 ft. However, limitations arise when ventilating such mining systems. In deep advance mining, there would be no workers at the face to advance ventilation tubing or curtain manually. Traditional methods also provide no means for maintaining face ventilation after the miner backs away from the face. U.S. Bureau of Mines research is studying means to provide effective ventilation at cut depths beyond the current limit of 4D ft. Several innovative ventilation schemes are currently being considered. One such method is the use of a jet fan to ventilate a deep cut. A jet fan is simply a freestanding fan using little or no ducting to direct the ventilation flow. Jet fan testing in a 90-ft entry revealed that higher exit velocities and greater penetration depth occurred when various configurations were used to confine and direct the air flow. Additional testing also indicated that 2,200 cfm of fresh air was delivered to the face? 90 ft distant when a check curtain was used to limit entrainment around the fan. Without this curtain, this quantity dropped to only 1,000 cfm. This testing indicated that a jet fan was capable of providing ventilation to a distant face area. It also highlighted potential problems, such as recirculation at the fan and reentrainment in the jet flow. Despite these potential problems, jet fans may be adequate for ventilating cuts exceeding 4D ft.

Jan 1, 2010

By G. St. J. Perrott, N. A. Tolch

"The testing of explosives for permissibility for use in coal mines was begun by the technologic branch of the United States Geologic Survey in February, 1909, and continued by the United States Bureau of Mines from July, 1910; this testing has been carried on from year to year as the explosives were submitted by manufacturers. As a result of these many years of testing for permissibility a large amount of data has accumulated regarding the characteristics of permissible explosives. The manufacturer expects a sample of explosive submitted for test to meet the requirements for permissibility, otherwise the sample would not be submitted. However, in spite of the careful regulation and preparation of the formulas a certain percentage of explosives fails to pass the gallery tests. It is therefore interesting to note the proportion of failures at the gallery for a given composition of explosive. The fact should be emphasized that this discussion deals with all explosives submitted for test, both those which passed the tests and those which failed to pass. Explosives that failed to pass the tests were never designated as permissible explosives and have never appeared on any list of explosives permissible for use in coal mines.The Bureau of Mines classifies permissible explosives in two ways, according to the quantity of poisonous gases produced and according to the characteristic ingredient of the explosive.4 In this paper only two types of the latter classification are considered, as follows:"

Dec 1, 1929

By John Nagy

The Bureau of Mines adapted thermal theories explaining combustion of gases to correlate parameters affecting ignition of dust dispersions. The dust dispersions were ignited in a Godbert-Greenwald furnace at atmospheric pressure. Ignition temperature and the concentrations of fuel, admixed inert powder, and atmospheric oxygen were related mathematically. Values for these parameters obtained in laboratory experiments for cornstarch agreed with theory. The developed equation permits extrapolation; the predicted upper igni-tion limits correspond with limited experimental data from laboratory and large-scale tests. Explanation of the effect of fineness of dust on ignition parameters is attempted by introducing a surface-area constant to modify the activation energy. Arguments are presented to show that the ignition process is a solid-gas phase reaction rather than an ignition of prevolatilized gases.

Jan 1, 1966

By C. Edward Chamberlain

A Bureau of Mines procedure was developed for the analysis of volatile matter in airborne coal dust-rock dust mixtures prior to, and resulting from, coal mine fires and explosions. Dust in the 10-to 20-mg weight range can be analyzed. Volatile matter is determined by a greatly scaled-down version of the empirical macro-scale method used by the Bureau. The alkaline earth carbonates in the rock dust are dissolved in acid prior to the volatile matter determination of the residue, and the rock dust content is calculated from the analysis of calcium and magnesium by atomic absorption.

Jan 1, 1974

By Karl Oltay

A series of 15, stations beginning with Potsdam and Budapest and ending with Budapest and Potsdam were occupied inn the period August, 1908, to January, 1909. The intermediate stations were all at points which had been connected by Baron Eötvös with torsion-balance traverses. The observations were made with an invariable pendulum of the standard four-pendulum type of instrument of the Geodetic Institute, made by Stückrath at Berlin-Friedenau. The observations at each of the field stations lasted-one to three days with one exception; two or three time determinations were made; four to eight series of pendulum observations were made; the error of determination of the elevation of the instrument above mean sea level ranged from 0.30 meter to 1.10 meters, with the exception of the Arad and Baja stations, where the elevation was known more accurately and averaged about ± 0.8 m, which would cause an error of ± 0.25 x 10-3 dynes. No topographic correction was applied. The values for ?g were taken from Eötvös: Report on Geodetic Observations in Hungary, especially Observations with the Torsion Balance, Budapest, 1910. The differences in ?g as determined, by the torsion balance and by the unvariable pendulum were: Kuvin-Hidegkut 1.2 km. 0.001, Livada-Kuvin 9 km. 0.001, Pankota-Livada 13 km. 0.004, Kuvin-Arad 20 km. 0.000, Pankota-Arad via Kuvin 42 42 km.0.005, Pankota- Arad via Kurtics 50 km.0.000 dynes. Oltay concludes that if the stations are close enough together and if the terrane is rather flat, the measurement of ?g with the Eötvös torsion balance is as accurate as with the invariable pendulum. -- Donald C. Barton.

Jan 1, 1929

By A. T. Iannacchione

The Bureau of Mines established geologic factors affecting the mining of the Lower Kittanning coalbed to aid in coalbed minability studies and examined the occurrence of "wants" (places where coal is missing) and types of unstable roof rock strata. Trends established from mapping, including prediction of areas of high methane emissions, were extrapolated to unmined areas. 'Wants' in the coalbed are of two types: Erosional and depositional. Erosional features occur where north-south-trending sand-filled channels cut into the coalbed. Variations in depositional environments have caused the coalbed to "split" into several thinner units. Slickensides, commonly indicative of unstable roof, are adjacent to and on the underside of sandstone channels; they were caused by differential compaction and by soft sediment sliding along the contact between the sandstone and adjacent shale. The frequency of unstable roof also increases where the interval between the Middle and Lower Kittanning coalbed is less than 30 feet. The zones of weakness at the contacts above and below the Middle Kittanning coalbed are the controlling factors for unstable roof in these strata. Methane emissions from the coalbed are controlled primarily by depth, fracture permeability, and rank of coal. Local geologic factors are coalbed thickness, associated rock strata, structure, and proximity to outcrop.

Jan 1, 1979

By Edmund Shaw

This paper is one of a series being prepared by the United states Bureau of Mines describing mining and milling methods and costs at industrial mineral plants throughout the United states. These papers are designed to disseminate technical information regarding the methods and equipment used. The cost tabulations represent operating expenditures only and not total production costs. It is recognized that publication of total production costs might, in many instances, cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention' of the reader? is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. P. J. Weisel, Inc., with office at La Habra and plant at Corona, Calif., is the only local company that produces sand for the Los Angeles glass factories, although silica sand for other purposes is produced in other parts of southern California and the adjacent portions of Nevada. The deposit at Corona consists of coarse sand imbedded in a whitish clay and differs greatly from the other deposits, which are fine-grained sandstone that must be crushed before it can be screened and washed. The preparation of Corona sand has to be thorough and includes grinding in tube mills, repeated washing and rinsing, removal of dust by air separation, and magnetic separation of iron and other minerals. This requires a plant with a complicated flow sheet. The first plant built did not make a. satisfactory glass sand, and many additions and changes were necessary. It is thought that the present flow sheet will remain substantially unchanged until a new plant is built. The design of a new plant would be simpler, but the process would be the same.

Jan 1, 1937