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By John W. Mentz

Phase I study efforts addressed: 1) acid mine drainage formation theory; 2) effects of inundation in reducing acid mine drainage formation; 3) summary information on the types of acid abatement technology currently available and the problems inherent in each; 4) analysis of two potential means of partially inundating abandoned segments of active underground mines to reduce acid formation. This subsequent Phase II Draft Final Report addresses all of the above, but concentrates on and defines Item 4. Seal construction techniques were taken through five logical steps as follows: A) Location Analysis; B) Coal Barrier Pillar Analysis: C) Ground Water Analysis; D) Design Considerations: E) Economic Analysis. The design details of both low wall dams and section seals were discussed in a series of segments: a) Case Histories; b) Feasibility Analysis; and c) Design (including representative calculations). Study efforts showed that both concepts are feasible only in certain mines where the geologic-hydrologic physical makeup is suitable to contain a mine pool. Low wall dams in particular were found to have extremely limited applicability as a means of pollution reduction. Section seals, while clearly dependent upon site specific conditions, have a some what broader range of utility and are more effective in pollution reduction. The proven dramatic reduction in acid mine drainage attributable to inundation makes this a concept that must be considered.

Jan 1, 1981

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

1. Introduction This document represents Part II of our final report on the development of a "Remote Sealing System for Extinguishing Coal Mine Fires. " It is a technical report which summarizes the results of system development and field demonstration. Part I of this two - part final report is an Operator's Manual for the application of the Remote Sealing System to a coal mine fire. 1.1 Background When coal mine fires go out of control and can no longer be fought directly, the standard fire fighting technique is to construct air-tight seals in the mine passages leading to the fire area so'--,that the oxygen supply to the fire is". cut off. Ultimately, it is desirable to isolate the fire zone in such a way that normal operations can resume in the remainder of the mine. The construction of seals in the- mine causes the atmosphere to pass through a toxic and explosive phase. Explosions, if they occur, are not only hazardous to the men working at the sealing operation, but can also undo much of the sealing work which has already been accomplished. Sealing of passageways surrounding the fire zone from within the mine is extremely difficult and dangerous. Methods for direct sealing are detailed in "Control of Mine Fires'. 1 An alternative to this approach is the technique of remote sealing. This involves drilling boreholes which intersect the mine passages at the locations where the desired seals are to be constructed. The seals are then constructed by pouring material down the borehole and filling a segment of the passage from bottom to top. During this operation, there are no personnel in the mine, all operations taking place on the ground surface.

Jan 1, 1973

By Patricia R. Devine

This appendix documents the mathematical approach to deriving the components of change presented in this report. The formulation closely follows that contained in Chapter IV of the documentation for the BEA 1977 Input-Output Tables.' The basic elements for the calculations include the "use" matrix (U), the "make" matrix (M), and any of the ten columns of final demand (generically represented by the symbol y). The use matrix contains information about changes in the technological processes of production, while the make matrix describes the nature of secondary product production in each industry. We adhere to BEA conventions in maintaining careful distinctions between commodity output (c) and industry output (x). The industry-by-industry 1-0 tables supplied by NYU for use in this analysis are square matrices, with the number of commodities and the number of industries both equal to 85. The BLS table for 1982 (commodity by industry) was aggregated and adjusted to be consistent with the earlier tables. The three basic steps for estimating components of change proceed as follows for each column of final demand. 1) Calculate the actual change in output of each commodity for each of the four time periods: 1963-72, 1972-77, 1977-82, and 1963-82.

Jan 1, 1988

By F. D. DeVaney

In the course of the investigation by the U. S. Bureau of Mines and the Missouri School of Mines and Metallurgy at the Mississippi Valley Experiment Station at Rolla, Mo., on the beneficiation of the low-grade manganese ores of the country, some samples from the Cuyuna District, Linn., have been examined. The work was done under the direction of W. H. Coghill, supervising engineer of the Mississippi Valley Experiment Station. Joseph and Kinney in writing about the relative importance of Minnesota deposits of low-grade ore compared to the total reserves say: "***It has been estimated that 26 to 35 million tons of ore contain 5 to 35 per cent of manganese, and the total domestic tonnage is from 75 to 48 million tons. The mean of these values is 30.5 million and 42 million tons, so it is seen that about 75 per cent of the reserves are in Minnesota." The manganese-bearing ores of the Cuyuna district maybe roughly grouped into two classes. The most abundant ore is of the low-silica, low-manganese, and high-phosphorus type called brown are. The other type is the so-called black ore, which is characterized by a higher manganese and silica content and by a lowe phosphorus analysis than the brown ore. As a general rule the brown ore carries less than 10 per cent of manganese while the black ore contains about 15 per cent and sometimes as high as 22 per cent of manganese.

Jan 1, 1930

By T. Kessler

As part of a respirable mine-dust research program at the U.S. Bureau of Mines, spark-source mass spectrometry has been used for the semiquantitative determination of trace elements (200 ppm weight or less) in raw coals. In addition, several minor and major elements have been determined using this technique. Sixty-four elements ranging in concentration from 0.01 to 41,000 ppm weight were determined in one anthracite, two mvb, four lvb, and six hvab raw coal samples. The samples represented 10 coal seams located in Pennsylvania, West Virginia, Virginia, Utah, and Colorado.

Jan 1, 1973

By A. J. Farstad

Recent advances in microcomputer technology have opened the way for systems which can track the location of underground mining personnel from the surface. A computerized system has been designed which is capable of not only tracking the location of the miner but also of monitoring underground parameters, communicating between work stations and sounding alarms when underground conditions are judged to be unsafe. For the system described herein, the locations of the underground personnel are detected by a network of underground terminals which routinely emit RF pulses to interrogate miniature transponders worn by the miners. Each transponder is uniquely programmed to delay its response in such a way that the RF terminal can identify the individual transponders by the time slots in which the responding pulses are received. The underground terminals are then interrogated by the host computer on the surface which keeps a running account on underground mine conditions and personnel. The underground portion of the system is designed to operate even during mine emergencies, deriving its power from rechargeable battery supplies which are float charged during normal operation. Nine mines were visited on this program and the industry reaction to the system was generally favorable. By slanting the system design for daily use in the mine, the chance of its acceptance by the industry is enhanced. Furthermore its likelihood of being operational in the event of an emergency is significantly increased.

Jan 1, 1981

By John S. Dunning

This paper is one of a series describing methods and costs of recovering sand and gravel from deposits in the United States and deals directly with the operations of the Atlas Sand, Gravel and Stone Co. at Farmington, Conn. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local expenditures only and not total production costs. It is recognized that publication of total costs might in some instances cause embarasement 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 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 may ensue.

Jan 1, 1933

By Alan G. Mayton

The Bureau of Mines conducted a study to (1) determine from laboratory tests the feasibility of a photographic method for determining reflec-tances that may be applied to measuring in-mine mineral reflectances and (2) formulate a procedure for collecting and analyzing the data. The method uses a 35-mm camera with automatic flash and a gray-scale re-flectance standard to collect on film the reflectivity data in under-ground mineral mines. After the film is processed, the data on the photographic prints are analyzed in the laboratory with a photometer. Test results show the photographic method can provide values of reflec-tance to within ±5 pet of full scale (full scale = 100 pet). The method's usefulness for determining reflectivity values, within similar limits of absolute percent error at the lower end of the scale, however, has not been completely resolved by the study and consequently warrants further investigation. The method offers an acceptable means for collecting and analyzing reflectivity data for reflectivities at the higher end of the scale, i.e., 50 pet or above; it should be used with caution when reflectivity values are below 50 pet. Four films were evaluated; all gave relatively satisfactory results.

Jan 1, 1987

By G. F. Kuncir

The time-cost-risk analysis described herein was performed as part of an evaluation of the Advancing Oil Shale Mining Technology Program performed by The Aerospace Corporation. The objectives of this analysis are to assess the feasibility of the program relative' to time and cost constraints, and to determine the probabilities of achieving various technological goals. A combination of standard program planning and analysis techniques were used to achieve these objectives. These included a critical path analysis, a resource allocation analysis, and a risk analysis.

Jan 1, 1977

By Steven D. Wirch

Abandoned underground coal mine areas must either be sealed or ventilated to comply with federal mine regulations. Ventilation of these abandoned areas is often impractical due to roof falls and inadequate primary mine ventilation. If the area is sealed, a very complex ventilation system is set up. In which the gob "breathes" in and out due to barometric pressure fluctuations. The Gob Assistant is a computer program (for use on IBM compatible personal computers) which allows the prediction of air flows into and out of a sealed mine area. Gas flows with applicable control techniques are also modeled. This information is presented to the user who will decide which control technique, or combination of techniques will ultimately be applied. The Gob Assistant is an intelligent gob simulator that can reduce the guesswork involved in predicting the effects of sealing and control techniques before they are applied. This paper provides the fundamental principles upon which the Gob Assistant is based, verification of these principles, and an explanation of how these principles were integrated into the Gob Assistant.

Jan 1, 1988

By J. J. Demeter

Experiments were conducted in 2- and 4-inch-diameter standpipes to evaluate the effectiveness of standpipes as pressure seals. During the experiments, these standpipes conveyed Alan-Wood magnetite (60 to 230 U.S. standard sieve mesh) by gravity flow from one vessel to another of relatively higher pressure. The information obtained has been helpful in a Federal Bureau of Mines investigation of how to make either synthesis gas or hydrogen by a modified steam-iron process employing a continuous recycling stream of granular iron-iron oxide at temperatures of 600° to 900° C. In this process the mixture of granular material flows by gravity from a reduction vessel at low pressures to an oxidation vessel at higher pressures. Data from the 2- and 4-inch-diameter standpipes indicate that it would be practical to use a standpipe as a pressure seal between the reductor and oxidizer. Investigators found that, by gravity flow, the standpipe could convey the Alan-Wood magnetite against pressure gradients up to 1.07 pounds per square inch per foot of column height.

Jan 1, 1961

By T. C. Atchison

This report describes a mobile laboratory designed and constructed by the Bureau of Mines in 1950 to meet the needs of an experimental blasting research program. The laboratory has facilities for making; film recordings of 16 simultaneous transient electrical signals over a broad range of amplitude, frequency, and duration. The signals are recorded with specially designed oscilloscopes and high-speed drum cameras. Each of the 16 channels records on a separate strip of 35-millimeter film by using interchangeable input units, transducers having different sensitivities and output impedances can be accommodated. The laboratory can be used to record both steady-state and transient phenomena originating as electrical voltages or capable of being converted to electrical voltages by appropriate transducers. Thus, the laboratory can, be used in studying various types of vibration problems or high-speed phenomena, such as ground and building vibrations, machinery vibrations, airborne vibrations, electrical-circuit switching phenomena, millisecond timing, and seismic phenomena occurring when rock is broken by explosives.

Jan 1, 1956

By Charles D. Wood

"Selected Topics,? in reviewing the control of emissions from diesel engine powered equipment used in underground mining, explores these fields of interest: hydrogen as fuel; lubricating oil as a source of particulates; applicability of stationary source scrubbers; worldwide diesel exhaust scrubbers; instrumentation technology for measurement of N02; control of emissions through application of sensors and microprocessors; use of fuel additives; technology transfer of marine diesel practice; technology required to use 4-stroke, aftercooled, turbocharged, direct injection engines; oxidation and reduction catalysts for diesel engine exhausts. "Selected Topics? makes recommendations for research and provides a bibliography and lists of references.

Jan 1, 1979

By Oliver Bowles, J. E. Crawshow

A line of cordeau detonating fuse was placed in hole No. 2, no electric detonators being used in the hole. After 12 or 13 cases of 40 per cent nitro starch powder had been poured into the hole in loose form, it was found that a space of only 17 ft. remained for stemming. It was decided that space for an additional case of powder might be obtained by tamping the charge. The tamping was done with a heavy plunger, about 3 or 3 inches in diameter and 10 inches long, made of lead with an iron core with an iron eye in the top to which a 3/4 inch rope was attached, and weighing between 30 and 40 pounds. This weight was intended for use in sinking explosive in wet holes, and not for tamping. It is estimated that the tamping had continued at least 10 The quarry superintendent had gone a considerable distance for a box of powder, returned, and reached a point about 10 feet from the hole, minutes.

May 1, 1920

By Virgil A. Marple

It was the purpose of this contract to conduct research in several different areas of instrumentation used to determine the quantity of respirable dust in the mining atmosphere. One area of research was in evaluation of instruments including several respirable dust monitors, several types of photometers, and a QCM cascade impactor. An instrument evaluation chamber was developed to aid in evaluating the instruments in a dust atmosphere. Another area of research was investigations into new instrumentation concepts, such as a virtual impactor/photometer instrument, a new optical device which can be used as either an optical particle counter or photometer, a new personal respirable sampler, which employs an impactor instead of a cyclone as a preclassifier, and the development of a new cascade impactor, which deposits the particles uniformly on the impaction plate. Another area of research included the use of many of these instruments in two field studies, including a silica sand plant and a tungsten mine.

Jan 1, 1981

By J. W. Faul

[The Bureau of Mines initiated an extensive research on coal-mine ventilation factors in 1922, large- scale tests being conducted in its experimental nine near Bruceton, Pa., over a period of two years. A comprehensive report an this work is in course of preparation, but in order to place the practical results before the mining fraternity immediately and in condenses form, the more important features will be presented in a number of short papers. The present report is the first of a series dealing with the resistance of coal-mine entries to the flow of air and considers only entries in which there are no obstructions other than the natural roughness of the ribs, roof, and floor.]

Jan 1, 1924

By J. A. Organiscak

This paper examines methods for limiting occupational silica exposures for roof bolting personnel in underground coal mining. A canopy air curtain and an air tube were evaluated as means to provide filtered air over the breathing zone of these personnel. Laboratory testing showed that dust reductions beneath the air curtain and air tube approached 60 percent and 40 percent, respectively, with low interference air velocities. The data also showed that dust reductions were highest for positions closest to the device and that these levels decreased with distance. This paper also evaluates a metal rake, a flexible insert, and a rigid insert for cleaning the roof bolter dust collector box. Less dust was produced when using the rigid insert. Surprisingly, the flexible insert was sometimes no better than scraping or raking the dust onto the mine floor. However, little dust got on the coveralls when using either of the inserts.

By Will H. Coghill

[The supply of gravel spar and of acid spar is not well balanced. Gravel spar -- 85 per cent flourspar, 5 per cent silica -- gluts the market, whereas acid spar -- 98 per cent fluorspar, 1 per cent silica -- is somewhat scarce. Hence it is desirable to convert some of the gravel spar into acid spar. Knowledge of this condition prompted the Franklin. Fluorsrar Co. at Paducah. Ky., to enter into cooperation with the U. S. Bureau of Mines and the Missouri School of Mines and Metallurgy to improve the methods of fluorspar, milling so that morn acid spar would be available. The fluorspar company detailed Mr. Omar Greeman for the work. During the course of the investigation, while Mr. Greeman was also doing work for a master's degree in the School of Mines? an extensive study was made of gravity concentration of fluorspar ores. Decrepitation by heat treatment was also given a laboratory try-out. A part of tie time was spent on flotation; these notes relate only to the flotation. The results of one of the flotation runs is appended. The test was made in a 500-gram mechanical-agitation machine. The sample was ground to 100-mesh in a pebble mill.]

Jan 1, 1928

By K. E. Tame

An alkaline leaching procedure for recovering uranium from a submarginal 0.1 percent Ug Og calcareous carnotite ore from the Shiprock , N. Mex . , area was investigated . A recovery of 72 percent of the uranium was attained in a preliminary test embodying the commonly accepted practice of ( 1 ) alkaline leaching at 90° C , ( 2 ) multiple stage filtration and washing for recovery of a clear pregnant solution , and ( 3 ) caustic precipitation of uranium as sodium diuranate , with recycle of the barren solution to the leaching and washing circuits . Ion exchange resins were used in a second , less orthodox test that comprised ( 1 ) sodium carbonate leaching of minus 10- mesh ore at 90 ° C to dissolve the uranium , ( 2 ) filtration to recover the leaching reagent for reuse , (3 ) recovery of the uranium- bearing solution in the filter cake as a pregnant slime slurry by repulping of the filter cake followed by a sand- slime separation and countercurrent decantation (CCD ) washing for rejection of the sand fraction , (4 ) recovery of the dissolved uranium from the pregnant slime slurry by resin- in- pulp (RIP ) , ( 5 ) elution of the uranium from the resin with a solution of ammonium chloride acidified with hydrochloric acid , and (6 ) precipitation of the uranium with ammonia gas . About 83 percent of the uranium was extracted from the ore and 95.5 percent of the dissolved uranium recovered by ion exchange . Improved laboratory results were obtained using the RIP process , but larger scale tests would be necessary for economic evaluation of the two processes .

Jan 1, 1964

By Oliver Bowles

The United States Bureau of Mines has within its ranks a group of engi- neers who are engaged in working out quarry problems, the solution of which will be of general benefit to the industries involved. The problems undertaken are approached in a systematic and thorough manner, all the evidence for and against any proposed change or new development being collected as carefully as an attor- ney would prepare his data on an important case. Unlike the attorney, however, the Bureau engineer does not take sides; his judgment is based entirely and in- partially on the array of facts presented. In order to gain the desired infor- mation he visits many plants, consults with the leaders in the industry, works out experiments in his laboratory, and supplements this information with a stu- dy of all available literature already published on the subject in any part of the world. As an engineer who has for eight years conducted such inquiries in the stone industry, I propose to discuss the Bureau of Mines viewpoint; and it may be of interest to consider with me in a brief and general way the engineer's method of looking at quarry problems, and some of the results attained through past and present labors. While the Bureau has conducted no investigation directly for the crushed- st one industries, two years of investigative work at cement-plant quarries, and work now being conducted at lire-plant quarries, has a very direct bearing on the problems of the crushed-stone industry, since stripping, drilling, blasting, loading, and transportation are similar in many respects in all stone quarries. The results of cement-plant quarry investigations are to be found in Bureau of Mines Bulletin #160. (b) Two short papers on lime-plant quarry problems have been issued in mimeographed form as Serial #01 (c) and Serial 3 (d).

Jan 1, 1923