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By G. L. Neumann

In October 1949 the College Park Branch of the Mining Division instituted a survey of the New England pegmatites. Many of the New England pegmatite deposits were superficially examined, and the Bumpus quarry in Albany, Oxford County, Maine (see fig. 1), was selected for a diamond-drill exploratory-development project to supply information for developing more economical mining methods and no increasing production of beryl and other scarce minerals associated with pegmatitic intrusives. The Bumpus quarry has been mined intermittently by three operators since it was opened in 1927. At the time of drilling, the vein or dike (see figs. 2 and 3) had been mined to a depth of 60 feet for a strike length of 280 feet. The dike averages 40 feet in thickness and dips 50 degrees southeast. The Bureau of Mines drilled seven diamond-drill holes between September 27 and November 27, 1950. These holes showed that the dike persists for at least 350 feet to the east and probably 200 foot to the west of the present excavation. The drilling also indicated that the dip, as exposed at the surface, continued unchanged at 500 to a depth of at least 50 foot below the pit. The dike was not delineated, although it fingered out as pegmatite interbanded with Granite, diorite, and gneiss in diamond-drill hole B-4, approximately 250 feet west of the pit. Further drilling will be necessary to find the extent of this pegmatite dike and to determine the safest and most economic mining system.

Jan 1, 1952

By Donald P. Tuchman, Robert P. Vinson, Steven J. Page

Researchers at the National Institute for Occupational Safety and Health (NIOSH) have long used stationary tapered element oscillating microbalances (TEOMs®) in laboratory settings. They have served to assess the mass concentration of laboratory-generated particulates in experimental , dust chambers and they provide a reference method for comparison with other particulate- measuring instruments. Current NIOSH research is focused on further adapting TEOM technology as a wearable personal dust monitor (PDM) for coal mining occupations. This investigation's goal is to help identify, quantify, and provide means for resolving certain TEOM- related error. The present research investigated bias caused by thermal effects on filter assemblies. New filters used in the PDM for 8 h tests show an average positive bias of 25.5 pg, while similar tests of equivalent filters used in two 1400A model TEOMs show an average positive bias of 34.3 µg. The derived bias values allow correction of previously collected biased data. Also, pre- heating the filters for 24 h at 46° C shows significant bias reduction, with PDM pre-heated filters subsequently averaging -3.3 µg and 1400A TEOM filters averaging 5.9 µg. On a single-point comparison to gravimetric sampling, a 25.5 µg bias is only significant at low mass loadings. At 2.5 mg, this bias represents a negligible 1 % of the mass measurement. If ordinary linear regression is used, the bias is still insignificant. However, if the more valid weighted linear regression is used, it gives more weight to the smaller dependent variable values, which are more impacted by the bias. Consequently, what is 1% bias on a single high-mass value can translate into a larger bias percentage at high-mass values when performing a weighted regression on data that include a large number of low-mass values.

By E. P. Youngman

The law now in effect (January 30, 1931) in the Netherlands with respect to the prospecting for and the developing of minerals is regulated by , or based upon , the French Act of April 21 , 1810 , "Concernant les mines , les minières et les carrières ( Bulletin des Lois No. 285) . " A second edition of a compilation ( by Drs . Ccuvee and Ritter ) of the mining legislation of Holland , including this act with other legal requirements , was published in 1928 under the title of "De Nederlandsche Mijnwetgeving , " by H. T. Tjeenk Willink & Zoon , Haarlem. In this abstract reference is made to the Act of 1810 , the Royal Decree of September 18, 1818 , the Mining Act of 1903 , and the Act of June 20 , 1924 .

Aug 1, 1931

By S. B. Flagg, J. F. Barkley

In the past few years an awakened activity in power-plant econ- omies has resulted in a marked improvement in the equipment for generating and utilizing steam. Although the improvement in design and construction of steam-driven prime movers has been greater than that of the steam-generating equipment, the economies obtained with the more efficient engines and turbines have stimulated interest and activity in eliminating unnecessary boiler and furnace losses. Much attention has been given to the boiler room in efforts to obtain proper combustion of the coal, because of the importance of the coal item in costs of power production. As evidence of this increasing interest may be cited the record of the development within the past few years of new apparatus for the analysis of flue gases. Many new forms of apparatus have appeared, including those for the determination of carbon dioxide, oxygen, and carbon monoxide, and others for indicating and for recording the content of carbon dioxide only, as carbon dioxide content is usually a good indicator for the control of furnace operation. Because of the large number of steam-power plants operated by the Federal Government and the number of CO, recorders used therein the Bureau of Mines undertook to collect information regard- ing the practical application of such recorders. Articles published from time to time concerning CO, recorders have been mostly descrip- tive, giving little reliable information as to the results that could be expected from the various types of instruments in ordinary prac- tice, and most of the tests made have been of a laboratory nature. Tests of several different types of recorders were made under service and laboratory conditions in order to obtain needed information. The purpose of the Bureau of Mines in publishing the results is to show the factors which may affect the accuracy of a CO, recorder and the manner in which a recorder should be tested. Readers should note that the remarks on different recorders apply to the instruments tested and not to later instruments of the same makers. In the course of the tests the following details were determined: 1. The lag in recording changes of composition of a flowing gas. 2. The accuracy of each type of recorder.

Jan 1, 1916

Although early Spanish settlers used coal several centuries ago, significant commercial coal mining in New Mexico began in 1861, when the U.S. Army opened a mine to supply Fort Craig. Since then, coal from the state has been used to fuel railroads, lead and copper smelters, and other local industry. In recent years, lower-cost strip mining methods and an increased demand for coal by electric utilities in the Southwest have caused an increase in New Mexico coal production. The coal-bearing regions of New Mexico underlie about 25,000 square miles or20.6 percent of the total area of the state. However, the majority of coal-bearing regions lie under Indian lands that are regulated by the Office of Surface Mining (see Navajo and Hopi data on pages 72-75). Today, most of the coal produced in New Mexico comes from the San Juan Basin in the northwest part of the state and the Raton Area in the north central part. New Mexico's reserves are estimated to be 4.6 billion tons, about one percent of the national reserve. New Mexico's permanent regulatory program was conditionally approved December 3 1, 1980. Its Abandoned Mine Lands Program was approved July 17,198 1.

Jan 1, 1992

ESTABLISHMENT of an effective inspection system has been held essen¬tial to any international agreement that may be designed primarily to curb the testing of nuclear weapons. A number of reports and papers already have described basic inspection concepts and appraised various pro¬cedures, techniques, and methods as to their probable effectiveness in detecting and identifying violations under such agreement. This report results from a study of only one part of the contemplated inspection system, specifically the final phases embracing onsite investigations and mine examination techniques. The results and reports of earlier work were reviewed in detail, and subjects that were found to have been exhaus¬tively evaluated are recognized by reference and not redescribed here. In other instances, previously described techniques, methods, and clues were revaluated to define more clearly their practical value to the final objective of an onsite inspection. Previous documentation does not refer to a number of subjects, techniques, tools, clues, and methods considered by the study; this report treats these in detail, even though when applied singly or collectively their practical value may be questionable.

Jan 1, 1962

By L. C. IlsLey

So many subjects are covered in State mine-safety regulations that any attempt to compare different State laws in their entirety would be futile. On the other hand, if one selects a single phase or branch of safety work, such a comparison may prove profitable. The subject selected for study in this paper is limited to legislation or regulations dealing specifically with safeguarding (electric) motored equipment used in gassy mines. T When one reads glowing accounts of the safety activities being carried on here and there it is easy to believe that everything which is right and proper is being done to safeguard the mine.workers; but, when one takes time to look into the weakness of many State regulations, it is evident that there is still room for improvement. Undoubtedly it would have been much better for the safety of mines if electrical equipment had been introduced into mines 50 years earlier. If electricity had been in general use when the first mine regulations were pre- pared, those formulating the rules would have covered this hazard along with other hazards, but as electricity came in at a later period, safe mine legisla- tion regarding it has been woefully neglected. Today the United States in general is far behind most other coal-producing nations in the provision of adequate safety rules or laws for the installation and maintenance of electrical equipment and wiring. Returning to the subject of our study, approximately 30 of the 48 States mine coal. More than 20 of these States' produce coal in large quantities. How- ever, of the 30 States only four, 3 Pennsylvania, Utah, Washington, and West Virginia, have laws which specially call for the use of explosion-proof types

Jan 1, 1929

By H. P. Rue

For the proper control of gasoline treating plants there is need of a quick test for corrosion. In "sweetening" gasoline that is, in treating it to remove evil smelling mercaptans or to convert them to disulphides or sulphides the sodium plumbite ("doctor") method is generally used. This method involves agitation of the gasoline with "doctor solution's (sodium plumbite made by dissolving litharge in a solution of caustic soda) in the presence of free sulphur3. One of the common mistakes in the technique of this process is the addition of too much free sulphur, which will dissolve in the gasoline and cause it to be corrosive. In the operation of a continuous sweetening; or treating plant, a check on the corrosiveness of they product is imperative at all times. The copper-strip test commonly used in specifications take, so long to perform that the plant may fail to function properly for some time before the operator discovers it. The writer has investigated a rapid corrosion test method involving the use of metallic mercury, recently developed by Messrs. G. T. Granger, refinery superintendent, and A. B. Comstock, chief chemist, of the Barnsdall Refineries, Inc., Okmulgee, Okla. They have used this test successfully for several months in controlling the operation of their continuous treaters any have come to the conclusion that it has several advantages over the copper-strip test. Chief among these is the time caved, as the copper-strip test takes at least one-half hour, while the mercury test can be wade in about five minutes. It is very evident that this is an important item in controlling a continuous treater.

Jan 1, 1928

By Dean H. Ambrose

This paper presents a technique for representing and analyzing random motions and hazardous events in a computer simulated three-dimensional workplace, providing machine designers and safety analysts with a new technique to evaluate ways to reduce operator-machine interaction hazards. Technical data in this paper is based upon a project striving to reduce workers' risks from being hit by underground mining machinery in a confined space. By simulating motions of an operator's random behavior and a machine's appendage, researchers can accurately identify hazards, and use that information to form safe designs for mining equipment appendage velocity. Validating the model provided improvements in the operator's optimal viewing area, work task- starting positions, and operator's motions for a more accurate random behavior. Preliminary simulation results provided (1) an interesting approach to research data gathering in that there was no need for live subjects and test sites and costs associated with experiments become insignificant and (2) that the model was versatile by showing it was capable of accurately mimicking the range collision forces versus speed, operators' size, and risk behaviors found in actual industrial situations and showed (I) that response time significantly affects the number of collisions experienced by the virtual subject and (2) that analysts must be discerning with the model and not read more From the databases than what the simulation model was designed to deliver. Keywords: random human-motion, anthropomebics model, machine-operator hazards, mine safety

Provide a lighter, smaller apparatus for more gently supporting electrical cable as it is raised or lowered in a well as compared with the conventional method of using a winch and pulley. Approach The conventional method of running cable into a well is to use a winch to pull the cable over a pulley located at the end of a boom placed over the well. This has the disadvantages of being bulky and of placing a concentrated strain on the cable at the point where it moves over the pulley. These disadvantages are overcome by using a "Chinese finger" cable grip assembly to hold and release a multiple conductor cable.

Jan 1, 1986

By B. Dimitriades

Exploration of the photochemical reactivity of diesel-exhaust hydro-carbons is described. A smog chamber was built, and reactivities of diesel exhaust, gasoline exhaust, and propylene were measured at two chamber temperatures. Experimental data indicated the problems caused by instability of diesel-exhaust hydrocarbons. With reservations due to these problems, the results are interpreted to reflect comparable reactivities for diesel and gasoline exhaust.

Jan 1, 1971

By David P. Conover

The U.S. Bureau of Mines (USBM) has developed a computer-assisted Ground Control Management System (GCMS) for near realtime evaluation of underground coal mine ground conditions. The GCMS combines existing mine-monitoring system and sensor technology with automated computer analysis techniques to enhance the acquisition, analysis, and display of geostructural data. The GCMS, which combines mine structure data with other information, such as geologic conditions and mine layout, has provided information on mining-induced stress transfer and pressure buildup associated with several ground control events. The GCMS collects and analyzes shield-leg pressure, ground pressure, and strata movement data to evaluate the structural behavior of an active Western U.S. Iongwall coal mine. Field data are transmitted over a dedicated phone line to the USBM Denver Research Center (DRC) mine monitoring laboratory, 240 km (150 miles) from the mine site. Real-time collection, processing, and analysis of mine structure and shield pressure information has proved to be an effective method for near-face ground conditions while mining progresses. The GCMS provides the mine operator with information to rapidly identify and manage potentially hazardous ground conditions while mining is in progress.

Jan 1, 1994

By L. D. Tracy

The first study of this subject hits been made in Illinois, but as opportunity affords, similar studies will be made in other States. It is hoped that the data obtained will assist the coal-mining industry to standardize the forms of leases, and so avoid some of the abstruse and ambiguous clauses which slay be found in many of them and the consequent liability of costly litigation. In some of the publications of the Illinois Mining; Investigations prepared under a cooperative agreement with the U. S. Bureau of Mines, the Illinois State Geological Survey and the Engineering Experiment Station of the University of Illinois, the coal areas of the 'State have been divided into eight geological districts, each district being treated separately. This report covers District No. VI of that classification, and it is hopped that studies of the other districts will be completed in the near future and similar results published.

Jan 1, 1926

By E. R. Cole

Bench-scale research at the Bureau of Mines has resulted in the successful development of a combination electrorefining-electrowinning method for recycling all the lead in scrap batteries. The method reduces energy consumption and eliminates toxic emissions, in contrast to present pyrometallurgical smelting, and the lead produced is pure enough for use in maintenance-free batteries. Anodes cast from molten lead scrap were electrorefined in 1-and 2-liter plastic cells using an electrolyte composition of 70 g/l Pb and 90 g/l free H2SiF6 (fluosilicic acid). Both reagent-grade and waste H2SiF6 were used. Cathode starting sheets were made from refined lead. Aloes, and later bone gelatin, and calcium lignin sulfonate addition agents were employed. The sludge remaining after separation of the lead metal was treated in a two-step leaching operation to solubilize the lead for recovery by electrowinning. Conditions for electrowinning were essentially the same as for electro-refining, except that insoluble Pb02-Ti (lead dioxide-coated titanium) anodes were used. The best results for both electrorefining and electrowinning were obtained with a current density of 170 amp/m2 and a cell temperature of 25° to 35° C. Cathode purity ranged from about 99.9 to 99.99+ pct Pb. Maximum energy consumption after 3 days, for electrorefining and electrowinning, was 90 and 700 kwhr per metric ton of refined lead, respectively.

Jan 1, 1981

By R. A. Beall

Consumable-electrode arc melting is now accepted throughout the industry as the best method for producing ingots of zirconium, titanium, molybdenum, and their alloys. In addition, the technique is widely used in laboratories for fusing samples of such metals as hafnium, chromium, tantalum, columbium, and thorium. The production of consumable electrodes from these metals presents some rather difficult problems, the accepted industrial solution being the use of heavy powder-metallurgy-type presses. This paper summarizes information on fabrication of consumable electrodes by this and alternative means, such as sintering, nippling, and welding lightly pressed compacts of scrap metal. A possible saving of considerable capital investment is shown in the case of sintered compacts. The electrical circuit components of a pilot sintering unit are analyzed. INTRODUCTION The consumable-electrode arc-melting process has been accepted by most of the industry as the best method at present for producing high-quality pure or alloy in-got from sponge titanium or zirconium. This technique is not particularly new, having been patented by Von Bolton (l)3/ in 1909 for melting tantalum. However, it has been applied to industrial-scale operation only in the last few years. Among the important contributions to this technique are the work of Kroll (2) and Parke and Ham (3) and the work reported by the Office of Naval Research (4). The Bureau of Mines-has added considerably to the knowledge of this process (5-9).

Jan 1, 1956

By R. Van A. Mills

This preliminary paper is intended to answer briefly some of the inquiries coning to the Bureau of Mines regarding the so-called "paraffining", of oil wells and methods of preventing and remedying that trouble. The increased difficulties in operation and the losses of production caused by the deposition of gummy and waxy hydrocarbons, commonly called paraffin, in the wells, tubing, other pumping equipment, and in the pores of the productive sands, have long been recognized but the trouble has not been overcome. The nature and causes of the trouble, together with some of the possible methods by which it may be diminished or overcome, are outlined below. Character of the Peraffining Materials. The so-called paraffin that collects in oil wells end in the pores of the oil-producing sands immediately around the wells, is generally made up of amorphous wax or uncracked paraffin, asphalt, or other gummy hydrocarbons mixed with more or lees water, oil, and inorganic silt. Some of the samples of this "paraffin" collected from oil wells in different fields and examined by the Bureau of Mines contain as mach as 20 per cent by weight of water and inorganic silt, whereas other samples are composed entirely of waxy hydrocarbons and oil. The inorganic silt accompanying this "paraffin" is mostly fine sand, clayey materials, common salt and finely disseminated precipitates of calcium and magnesium carbonates. Sulphates of calcium, barium, and strontium are less common constituents of the "paraffin."

Jan 1, 1923

By F. R. McDonald

This report presents a discussion of the spectra of 39 condensed thiophenes in which the structure includes at least 1 benzene ring. The vibrational bands present in three regions of the infrared spectra of these thiophenes were interpreted by comparing the similarities of the spectra of condensed thiophenes with the spectra of substituted benzenes. In the overtone-combination region 23 of the 39 condensed thiophenes had spectra which contained sufficient detail to be usable for correlating this region of the spectrum with the appropriate benzene spectrum. In the in-plane deformation region it was possible to make correlations for the vibrations of 18 of the 39 condensed thiophenes whose infrared spectra were studied. In the out-of-plane deformation region the C-H out-of-plane vibrations for hydrogen on benzene rings in the condensed thiophenes can be correlated using known data from substituted benzenes.

Jan 1, 1967

By Albert E. Long

Diamond-bit performance and cost data accumulated in core-drilling sandstones reveal significant trends of economic interest. Large-size, AA-Grade drill bort suffered less diamond loss per foot drilled than any other size or grade of diamonds assessed. Detailed analyses of the factors that affect diamond-bit performances -diamond size, diamond quality, bit size, bit type, percentage of core recovered, and physical characteristics of bit matrices -are assessed in the tables, graphs, and discussion. INTRODUCTION Since 1945 the Bureau of Mines has been compiling detailed performance records on diamond bits used in core drilling throughout the United States and Alaska. Analytical reports covering bit performance in various rocks are issued as in-formation on a significant number of bits used in anyone type of rock is accumulated. The first three such reports analyzed bit performance in gneiss,2/ schist,3/ and lime-stone and dolomite.4/ This report evaluates diamond-bit performance in sandstone. Data obtained from 627 bits, which drilled 42,665 feet on 45 different projects, are presented. The geographical distribution of the projects is shown in figure 1.

Jan 1, 1958

By Alfred E. Schwaneke

An improved maximum-bubble-pressure system using the Sugden twin-capillary method for measuring the surface tension and density of molten metals is described. Improvements include (1) internally ground capillary tips, (2) electronic pressure transducers, (3) micrometer adjustment of immersion depth for density measurements, (4) valuing arrangements to allow operation at other than atmospheric pressure, (5) temperature range to 1,100° C, and (6) recorder readout of pressures. Data for surface tension of mercury from 20° to 300° C are given.

Jan 1, 1970

By D. E. Traut

A fluidized, countercurrent ion-exchange system was developed, operated, and evaluated by the Bureau of Mines in support of its objective to help assure an adequate uranium supply for future national needs. The system consisted of integrated multiple-compartment absorption and elution columns in which the solution flows are continuous, except for short periods when resin increments are withdrawn. The exchange of uranyl sulfate between a simulated acid-leach-uranium solution and a strong-base, ion-exchange resin was studied, together with subsequent elution using an acidified sodium chloride solution. The effects of the number of compartments, compartment height, amount of resin withdrawal, solution flow rate, and column diameter were investigated. Also examined were the kinetic and equilibrium relationships for the absorption and elution steps. The experimental data indicate a strong interdependence between variables. Solution retention time appears to be a major limiting variable in the absorption process, while resin residence time is the determining factor in the elution process. The columns system was efficient over a range of conditions, but close control was needed for optimum operation.

Jan 1, 1978