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Provide the mining industry with a wireless surveying system for increasing efficiency in the drilling of methane drainage or exploration boreholes. Approach The Bureau of Mines has pioneered the technique of methane control by drilling long, horizontal drainage holes from within the mine complex. It was recognized during the early drainage projects that a major portion of the drilling operation was dedicated to hole surveying. In some cases more time was actually being spent on the surveying operation than on drilling. The large amount of time required for hole surveying was the result of having to pump an instrument to the bottom of the hole, then retrieve it with an attached wire line. Naturally as hole depth increased, so did the amount of time needed to perform the survey operation. If the survey operation could be improved it was obvious that overall efficiency in drilling of long, horizontal methane drainage holes would be greatly increased. The Bureau of Mines, therefore, developed, fabricated and tested in an operating coal mine a permissible wireless survey system specifically designed for small diameter methane drainage drilling. The prototype survey system was completed in 1982 and was given the IR-100 Award by Industrial Research and Development Magazine. A second generation survey system is currently being constructed using updated state-of-the-art electronic technology. The second generation system will be more portable, more reliable, easier to maintain, and less costly.

Jan 1, 1984

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

THIS PROGRAM TRANSFORMS FREE FORHATED BRANCH DATA INTO A FORMAT SUITABLE FOR INPUT TO THE PENNSYLVANIA STATE UNIVERSITY MINE VENTILATION SIMULATOR (PSU/HVS 1. BRANCH RESISTANCES ARE ASSUMED TO HAVE BEEN ALREADY CALCULATED, IIOWEVER THIS PROGRAM CAN BE EASILY MODIFIED TO HANDLE THE ADDITIONAL INPUT DATA REQUIRED FOR RESISTANCE CALCULATIONS IN THE PSU/MVSO THE PROGRAM IS WRITTEN IN FORTRAN IV WITH WATFIV.

Jan 1, 1977

The extrapolation of results from reconstructed laboratory soil columns to field conditions is difficult because of the limitations of laboratory experiments. Permeability and elution tests performed in the laboratory differed from the natural state in that the soil was sieved through 1/4 inch screen to remove large stones and roots, its density was controlled by tamping the soil into two-inch I.D. tubes instead of normal weathering, and water and latex were applied with a constant head of liquid. Tube wall effects are important in interpreting data. Conversely, interpretation of field results were confounded by non-homogeneities within the sample tested, a soil profile with gradation of permeability and density with depth, and uncontrolled weather conditions and seasonal changes that affected the results. Nevertheless, both laboratory and field tests showed that a specific latex did perform as a soil sealant. In view of these facts a soil box experiment was designed to overcome some of the disadvantages associated with the small laboratory soil columns and the field experiments. Two wood soil boxes 5 ft x 5 ft x 5 ft were built in the greenhouse at the Uniroyal Research Center. They were lined with plastic PVC sheeting provided with tubes every six inches of depth on one side of each box to measure water removal rates under saturated conditions. Tensiometer gauges were placed at depths of 6, 12, 18, 24, 36 and 48 inches and Bouyoucos blocs and resistance thermometers were positioned at 6, 24 and 48 inch depths. Each box was filled with a uniform sub-soil obtained from Ogdensburg, N. J. The texture of this soil was determined to be a sandy loam by the ASTM Hydrometer method, as shown below: [ ] The boxes were thoroughly wetted by sprinkling to abet settling and allowed to dry by draining to check seepage ports and functioning of tensiometers.

Jan 1, 1972

By Richard J. Mainiero, Sapko, Marcia L. Harris

Since 1988, there have been thirteen documented incidents in the United States and Canada in which carbon monoxide (CO) is suspected to have migrated through near surface strata into structures or other enclosed spaces as a result of nearby trench blasting or surface mine blasting. From these incidents, there are thirty suspected or medically verified CO poisonings and one fatality associated with these incidents. To better understand the variables contributing to this hazard, the National Institute for Occupational Safety and Health (NIOSH) carried out a small-scale field study to identify key factors that may contribute to the migration of CO through the ground. NIOSH conducted single-hole heavily confined experimental test shots to measure the radial pressure pulse as it propagated through surrounding monitoring holes to determine if a relationship existed between the pressure pulse and resulting CO measurements afterwards. NIOSH also monitored blasts at an airport construction site. Following the detonations, the concentrations of CO, nitric oxide (NO), and nitrogen dioxide (NO2) were monitored for several days in the surrounding satellite holes. The peak CO measurements relative to distances from the shots were compared. Pressure histories and peak particle velocities (PPV) were measured at monitoring boreholes. It was found that the differential pressures recorded within the boreholes give some indication as to the likelihood of CO appearing, whereas the PPV measurements do not seem to be as good an indicator for potential CO migration. In this limited study, changes in barometric pressure had very little influence on removing the trapped detonation products, whereas applying a vacuum to the monitoring holes was effective in reducing the entrapped CO concentration.

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Jan 1, 2012

By James Westfield, S H. Ash

Because of the increasing shortage of fuel in the United States, especially of residential fuel in the Eastern and New England States, it was essential that the maximum production of anthracite be obtained to help win the war and to prevent human distress. The nine railroads that depend on the anthracite region for a substantial portion of their business were not congested unduly with other traffic, because the region was not participating in industrial activities to the same degree as in many other sections of the United States; consequently, transportation of anthracite to the New England States, New York, New Jersey, and eastern Pennsylvania over a shorter rail haul than for any other fuel was desirable. The prevention of floods that would cause a loss of anthracite production was important to the war program. Every shutdown deprives the northeastern section of the United States of anthracite that is needed badly. Failure to prevent inundation of anthracite mines halts production, endangers the lives of workmen, damages, sometimes beyond repair, vital underground equipment, and threatens the permanent loss of a large portion of the Nation’s anthracite reserves. Funds were made available to the Department of the Interior, Bureau of Mines, for the fiscal year ended June 30, 1945, through a supplemental appropriation for anthracite investigations, one of which was to conduct inquiries and scientific and technologic investigations that have a bearing on the anthracite mine-flood problem. As part of the investigation, the Bureau proposed to obtain the cooperation of the anthracite-mining companies and the State in effecting a program to prevent the inundation of mines in the anthracite region. No large engineering projects were undertaken by the Bureau during the fiscal year ended June 30, 1945, on the anthracite mine-flood problem. Small projects were chosen that could be completed within 1 year to prevent loss of anthracite production at a critical time. It was believed that such projects would lessen the chance that flood water would inundate active mine workings.

Mar 1, 1946

By Charles L. Parsons

During the past year, in producing 500,000,000 tons of coal we wasted or left underground, in such condition that it probably will not be recovered in the future, 250,000,000 tons of coal; we turned loose into the atmosphere a quantity of natural gas larger than the total output of artificial gas during the same period in all the towns and cities of the United States; we also wasted or lost in the mining, preparation, and treatment of other important metalliferous and non- metalliferous minerals from 10 to 50 per cent of the year's produc- tion of such minerals. These losses serve to indicate the importance of inquiries and investigations by the Federal Government for the purpose of lessening the waste of essential resources-investigations on the same general lines as those looking to a reduction in the loss of life in the mining operations of the country and the far more exten- sive investigations looking to the more efficient production and use of agricultural products, both of which are being conducted by the Federal Government. In a consideration of the possible activities of the individual, the State, and the Federal Government in behalf of a less wasteful use of our mineral resources certain facts and principles should be kept clearly in mind, namely: That the present generation has the power, and it will exercise the right, to use as much of the country's resources as it actually needs; there can and there will be no such thing as stinting the present gen- eration by bottling up resources for the use of the future. That the Nation's needs are not likely to be curtailed; these needs will increase with the extent and diversity of the Nation's industries, and they will increase more rapidly than population increases, for the reason that the per capita consumption of mineral products is rapidly increasing; and That the men of this generation will not mine, extract, or use these resources at continuous financial loss to themselves in order that some- thing may be left for the use of future generations; there can be no such thing as a mineral industry without profits.

Jan 1, 1912

By C. B. Manula, R. L. Sanford, R. A. Rivell

Part I. DATA INPUT ALTERNATIVE 1

Jan 1, 1974

By C. D. McMaster, John C. Hartley

Three systems that monitor ventilating fans are described . These electronic monitoring systems automatically perform most of the operations required to conform with the provisions of the Federal Mine Safety Code in the event of fan failure or slowdown .

Jan 1, 1964

By Paul S. Lewis

Bench-scale experiment~ by the Bureau of Mines showed the gross effect of retention times ranging from 0.1 to 14.5 minutes on the conversion of high-volatile C bituminous coal to liquids and gases. The uncatalyzed coal was hydrogenated at 400°, 450°, and 538° C. and 500, 1,000, and 2,000 p.s.i.g. The percent coal conversion increased rapidly during the initial 3 minutes and asymptotically approached a maximum within 7 minutes at all conditions. Reasonably good correlations of coal conversion with time, pressure, and temperature were obtained. Temperatures up to 900° C. and retention times of about 1 minute are recommended for future experiments with the objective of producing only gaseous hydrocarbons and partially devolatilized coal suitable for use as solid fuel. The reactor contained 13 semicircular ledges, and the retention time was controlled by the rotation of scrapers which swept the coal from ledge to ledge. Only coal feeds that did not adhere to the internal mechanism could be used.

Jan 1, 1961

By Thomas G. Carnahan

The Bureau of Mines conducted research to simulate in situ leaching of a chalcopyrite ore. The purpose was to obtain a direct comparison between moderate-temperature and elevated-temperature in situ leaching of copper trom minus la-inch ore and to analyze the sulfuric acid and oxygen requirements of the leaching system. Experiments employing oxygen were conducted at 35° and 90° C on 362-and 367-1b ore charges, respectively, under flooded conditions and at 400 psig. At 90° C, 47 pct of the copper was extracted in 913 days of leaching; at 35° C, 27 pct of the copper was extracted in 915 days. Diffusion into and out of the ore fragments con-trolled the rate of leaching. Oxygen consumption was 1.46 lb/lb of copper extracted at 35° C and 3.15 lb/lb of copper extracted at 90° C. Sulfuric acid requirements of the ore were 5.49 and 7.48 lb/lb of copper extracted at 35° and 90° C, respectively.

Jan 1, 1982

By T. G. Carnahan

The Bureau of Mines conducted research to simulate in situ leaching of a porphyry copper sulfide ore. The purpose was to determine the effects on copper leaching of additions of NaCI to a conventional sulfate leach system and to analyze the oxidant requirements and the oxidation products that resulted from leaching of the sulfide minerals in the ore. Baseline sulfate and sulfate plus 2-pct-NaCl-leach-solution experiments employing 167-kg (367-lb) and 152-kg (333-lb) charges, respectively, were conducted. The minus 25.4-cm (10-inch) ore was leached at 90° C under flooded conditions with 2.8 MPa (400 psig) of oxygen bubbling through the system. Sixty-seven pct of the copper was extracted in 1,236 days of leaching in the NaCI experiment, whereas 47 pct of the copper was extracted in 913 days of leaching in the baseline experiment. Diffusion into and out of the ore fragments controlled the rate of leaching, which precluded enhancement of the leach rate by the chloride ions. The calculated oxygen consumption was 3.17 kg/kg of copper extracted in the baseline experiment and 3.46 kg/kg of copper extracted in the experiment to determine the effect of chloride ions.

Jan 1, 1982

By Martin H. Stanczyk

Two methods of recovering zinc from zinc ammonia complex solutions were investigated. One method studied was distillation of the ammonia from the solutions to recover a basic zinc sulfate, which after calcining to zinc oxide was reduced to metallic zinc using hydrogen at 900° C. The second method tested was electrolysis. The tests were made of synthetic and leach solutions analyzing about 80, 100, and 115 gpl (grams per liter) of Zn, NH3, and SO4, respectively. The leach solutions were prepared by oxidation leaching of a sphalerite flotation concentrate, assaying 55 pct zinc at elevated temperature and pressure. The distillation method recovered about 98 pct of the zinc in a product analyzing 97 pct zinc. Ammonia losses incurred during the leaching and distillation operations were about 0.1 lb per lb (pound per pound) of metallic zinc produced. Electrolysis of the solutions at a cathode current density of 25 amp per sq ft (ampere per square foot) yielded zinc deposits assaying in excess of 99.9 pct zinc. About 1.5 kwhr (kilowatt-hour) of power were consumed per pound of zinc deposited; the current efficiency was 72 pct. Other electrodeposition tests revealed that small amounts of ferric iron in the cell liquor were deleterious to electrolysis unless about 5 lb of glue per ton of zinc were present in the electrolyte. The use of glue and vigorous agitation of the electrolyte gave smooth zinc deposits from solutions containing as much as 0.1 gpl iron.

Jan 1, 1962

By Lester G. Morrell

THE WORLDWIDE economic expansion that has characterized the first 3 years of the 1960's continued through 1964 and was reflected in North America by strength in the industrial economy of the United States, which again was dominant. Advances in production were recorded in virtually all industries, including the mineral industry; 1964 mineral production established a new high, 5.4 percent above the previous peak recorded in 1963. However, the percentage increase in value of North American mineral production was slightly below overall economic growth. For industry in general, consumer demand held firm throughout the year and overall commodity prices averaged 2 percent higher than in 1963. Wages and salary payments also were up. With the single exception of the dock strike in the United States, the year was free of serious labor troubles and unemployment in both Canada and the States was at a low level. Despite the Viet-Nam situation, relatively tranquil international relations contributed to the forward movement of North American business. Total gross national product (GNP) for Canada and United States, in current dollars, was estimated at US$672.2 billion; 6.8 percent above the previous year's figure. Combined national income in 1964 amounted to US$546.9 billion, which was nearly 7.0 percent more than in 1963. In 1964, gains were recorded in each of more than 50 metals, nonmetals, and fuels commodities that comprise the North American output. The greatest category increase was 13 percent in metals, which was in part attributable to the 14 percent rise to a new record in value of iron and steel in United States, a 29 percent higher value of Canadian iron ore and a 57 percent rise in Canadian zinc. Despite a moderate decline in prices of iron ore and iron and steel products, generally favorable markets and rising prices for metallic ores and metals were a stimulant to the metals industry. Nonmetallic materials, with a total value in excess of US$5.25 billion were 7.3 percent higher than in 1963. High levels of highway and building construction and expanding demand for fertilizers and chemicals continued throughout the year. Noteworthy output increases were recorded for lime,

Jan 1, 1966

By David C. Oyler, William P. Diamond

Three long horizontal holes were drilled from a directionally drilled sur¬face hole at the Emerald Mine near Waynesburg, Pa. The purpose was to adapt the technique of directional drilling for use in draining methane from coalbeds. A 504-m (1,652-ft) long, 76-mm (3-in) diam¬eter, circular arc pilot hole was drilled, using a downhole mud motor, to enter the Pittsburgh coalbed at a verti¬cal depth of 305 m (1,000 ft). The hole was reamed to 222 mm (8-3/4 in) and was cased to a measured depth of 486 m (1,595 ft). Three 76-mm (3-in) diameter horizontal drainage holes were then drilled, totaling 2,909 m (9,544 ft) of horizontal hole. Improvements in drilling methods increased the average drilling rate from 20.4 m (67 ft) to 64.9 m (213 ft) per day. The cost of drilling the directional and horizontal holes (using a Government-owned drill rig) was $1,169,530, a figure inflated by inexperience and by delays caused by lost-circulation problems and fishing operations. An estimated total drilling cost of $960,000 (including rental of a drill rig) for an improved system, was determined by a detailed cost analysis. Initial gas and water production from November 1979 through May 1980 was low because of caving of the horizontal holes drilled in shale near the bottom of the casing.

Jan 1, 1982

By G. E. Rennick, F. E. Armstrong, J. Pasini, J. R. Abrams

An oil well penetrating the Pittsburgh bituminous coalbed in northern West Virginia was plugged and safely mined through 3 months later. A sensitive chemical tracer, introduced into the oil reservoir before the test, was not detected in the mine air following the plugging and during mining of the pillar and penetration of the well. Effectiveness of the plugging in preventing reservoir gas from entering the mine through the well hole was verified by continuous monitoring of the mine air for indications of sulfur hexafluoride, an inert gas detectable in amounts as minute as 112 part per billion. Expand- able cement and fly ash-gel-water slurry were utilized to seal the well above and below the coal seam. Three other wells were also plugged using various techniques.

Jul 1, 1972

By S. W. Lambert

In this Bureau of Mines investigation, production was monitored for 1 year at over 30 coalbed gas-drainage boreholes located in Alabama, Pennsylvania, and West Virginia. Results indicate that the quality of data gathered from such wells can be improved greatly if potential problems are anticipated and prevented in the early stages of well production. Major water-monitoring problems include solids buildup, freezing, the presence of gas in surface waterlines, and improper pumping interval settings. Such problems may be avoided by incorporating in the original well design waterline filters, sand screens, separator tanks, and systems to automatically control pumping intervals. Problems related to measurement of coalbed gas flow include large quantities of water vapor contained in the gas, especially during winter months; freezing and subsequent obstruction of flow; sudden, uncontrolled release of gas pressure; and solids buildup in metering equipment. The installation of commercially available items, such as filters, separators, and insulation, and the thoughtful application of a basic knowledge of coalbed gas reservoir characteristics will prevent most production-monitoring problems.

Jan 1, 1978

By D. L. Pool

To increase metal recoveries and to minimize pollution by improved extraction technology, the Bureau of Mines investigated a hydrometallurgical technique to recover copper, lead, nickel, and cobalt from lead smelter mattes. The metals were converted from insoluble sulfides to soluble chlorides using a HCI-CI2-02 leaching system. Parameters studied in a 50-gallon, glass-lined reactor were the ratio of hydrochloric acid to chlorine, chlorine consumption per pound of matte, oxygen reaction pressure, and temperature. The matte material used contained, in percent, 19.7 Cu, 52 Pb, 2.9 Ni, 1.5 Fe, 0.38 Co, 0.19 As, 0.41 Zn, and 0.12 Cd. Extraction of Cu, Pb, Ni, Co, and Cd ranged from 92 to 98 pct, with concomitant extractions of Fe and As of <0.1 pct. The Cu and Pb were recovered as electrowon metals, while the Ni, Co, and Cd were recovered as mixed hydroxides.

Jan 1, 1981

By J. T. Schimmel

The purpose of this investigation was to obtain complete information on some of the uses of a 24-inch-diameter auger in the underground mining of pitching anthracite beds. The auger was placed in operation early in 1958 to drive ventilation connections between coal gangways driven by a continuous miner. Although designed to drill rise holes only, it was used also to drill dip holes. The latter holes were drill id from an adjacent gangway to avoid interference between the auger and the continuous miner. These holes established immediate ventilation returns when intersected by the continuous miner. Bureau participation in the project covered 361 working days. The auger was used on 288 shifts, usually one 7-hour shift per day, and drilled 3,246 feet, of which 493 feet were reamed. The longest hole was 87 feet; hence the maximum drilling depth of the machine (rated at 100 feet) was not required. Holes drilled normal to the strike of the bed ranged from 30 to 66 feet deep, averaging 45 feet. The continuous miner drove gangways on 575 shifts. Thus, the auger worked one shift for each two worked by the continuous miner and was used on less than 80 percent of the workdays. The auger drove 24-inch holes 10 times faster than the larger, conventional openings could have been driven by usual mining methods and exceeded the workload for which it was purchased. Augering eliminates exposure to the hazards encountered in driving chute-work by conventional methods and provides adequate circular ventilation openings, which are strong in self support and are adaptable to reaming when required. With alterations, the auger may have limited use as a production machine in thin-bed pitch mining but cannot compete with established methods of thick-bed pitch mining.

Jan 1, 1962

By S. P. Signer

The Bureau of Mines conducted a series of field tests to improve the understanding of the support interaction mechanics between fully grouted bolts and coal mine roofs and to help lay the foundation for improved design and evaluation techniques. Strain gauges were installed on 14 fully grouted bolts placed in shale roof rock at four mines in Colorado, Illinois, and Pennsylvania to determine how load was transferred between the bolts and the rock. The results of field tests on elastic bolt behavior compared well with previous laboratory work and numerical models. The field tests showed that the anchorage length of grouted bolts installed in shale was slightly longer than the anchorage length determined in laboratory tests conducted in concrete blocks. The field results produced more variability because of geological variations. Tests run past the yield point of the steel bolt indicate that the yield zone varies significantly and translates down the length of the bolt anywhere from 4 to 22 in.

Jan 1, 1990