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By Steven R. Munts

In 1985, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied 39,420 acres of the 60,960-acre Skedaddle Wilderness Study Area in order to evaluate its identified mineral resources. There are no known mines or mining operations in the study area. None of the prospects or claims in or within a 1 mile peripheral zone around the study area have recorded production. At least 276 recorded lode, 6 unrecorded lode, and 29 placer claims have been located in and within about 1 mile of the study area. Approximately 191 of the claims are in the study area. Four of these were current in 1985; all four are wholly or partly inside the study area. None of the study area was being explored by private industry in 1985. Metallic and nonmetallic commodities present in the study area consist of gold, mercury, perlite, basalt, pozzolan, stone, and sand and gravel. Perlite is represented by a single deposit which contains 184,000 tons of subeconomic resources in and adjacent to the study area. No other sites contained identified resources. There are no other identified nonmetallic resources in the study area. Occurrences in and near the study area contain small amounts of gold and mercury in vein-type deposits and show characteristics similar to bulk-tonnage, low-grade gold deposits. No base-metal resources were identified. The gold and mercury mineralization and perlite deposit are spatially related to a volcanic center located in the Skedaddle Mountains. Prospects in the Skedaddle Mountains may contain both precious metals and perlite resources, but additional work is required to adequately delineate these areas.

Jan 1, 1987

By B. W. Haynes

This Bureau of Mines report describes the laboratory processing of manganese nodules and the results of tailings characterization obtained during the cooperative program with the Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) and the Bureau. Five technically feasible first-generation nodule processing methods were operated at bench scale to generate sufficient tailings and slags for physical and chemical analyses. A description is given for the laboratory operation of the individual unit operations of each process. The laboratory-generated tailings and slags were tested for physical properties, mineral content, elemental and ion content, and leachability for all five processes. The results of leachate testing using the Environmental Protection Agency extraction procedure (EP) toxicity test, the American Society for Testing and Materials shake extraction test, and the EPA-U.S. Army Corps of Engineers seawater elutriant test showed very low to negligible leaching of metals from the tailings and slags. Results of the EP toxicity test demonstrated that the wastes are nonhazardous as defined in the Resource Conservation and Recovery Act (Public Law 94-580).

Jan 1, 1985

By John R. Rhodes

The objective of this project was to investigate the feasibility of analytical techniques potentially capable of determination of Mg, Al, Si, S, Ca and Fe in 1 to 2 mg samples of respirable coal mine dust, in a total analysis time of not more than 10 minutes per sample, using equipment capable of being truck mounted for field-laboratory operation. It was not essential that the technique be non-destructive, but the chosen technique is, and this enables the analysis to be performed directly on the 37 mm diameter membrane filter on which the respirable dust sample is normally collected. The sensitivity requirements are therefore quoted in terms of the units of measurement, µg/cm2. The detection limit (3o of the background criterion) should be 0.5 µg/cm2 or less. The precision should be 5% or better, at concentrations above which the detection limit is not the determining factor.

Jan 1, 1972

By G. L. Fitzpatrick

A portable optical instrument for performing multispot laser vibrometry is described. The instrument is capable of measuring arrival times, surface motion frequency, and surface velocity and displaying these quantities in various useful ways. Sigma Research is currently pursuing the development of such optical measuring systems for the evaluation of structures in rock by non-contact interferometry methods. This work was sponsored by the U.S. Department of Interior (U.S. Bureau of Mines) under a Small Business Innovation Research (SBIR) contract number J0145075. The goal of the work was to develop a portable tripod mounted measuring system which can be set up at arbitrary distances (up to 30 meters) from a surface and project four in-line laser sample beams on this surface. A light receiving telescope gathers the scattered light from these four spots and provisions are made to mix this light with a reference beam from the laser. Four photodiodes are employed to determine the resultant interference signals which characterize the motion (particle velocity, frequency, amplitude) of the four illuminated spots on the surface under sudy. Information of this type can then be used to characterize the elastic or mechanical properties of the surface in question. In some cases (if more than four spots are involved) this surface information could be back propagated to draw inferences about the internal state of the material volume bounded by this surface.

Jan 1, 1987

By E. D. Calvert

The room temperature tensile properties of commercially pure titanium and seven titanium alloys prepared by skull casting were determined in the as-cast and heat-treated conditions. Data were compared with property data from tensile tests on wrought alloys of the same compositions in the as-worked and heat-treated conditions. The alloys evaluated were Ti-5Al-2.5Sn, Ti-6Al-4V, Ti-6Al-4V-lSi, Ti-6A1-2Sn-4Zr-2Mo, Ti-6A1-6V-4Zr-4Mo, Ti-6A1-6V-2Sn, and Ti-11.5Mo-6Zr-4.5Sn. Test specimens were prepared from both static and centrifugal castings and from plate fabricated by forging and rolling vacuum-melted ingots. The data indicate that the alpha and alpha-beta alloys have strength properties in the as-cast condition that are reasonably close to the strength properties of their wrought counterparts in the as-worked condition. An exception to this was the Ti-6A1-6V-4Zr-4Mo alloy for which insufficient data were available to form any firm conclusions. Fine-grained cast structures of Beta III (Ti-11.5Mo-6Zr-4.5Sn) were shown to be generally stronger in the as-cast condition than the wrought alloy in the as-worked condition except for the yield strength of one structure that was unusually low. Heat treatment of this alloy produced properties that were unpredictable. Indications are, however, that optimization of heat treatment parameters for each cast structure could produce strength properties equal to that of wrought materials.

Jan 1, 1974

By W. C. Holliman

This report on the characteristics of commercial aviation gasolines presents compilations of inspection test data furnished on their products by manufacturers of commercial grades of aviation gasoline, and special data obtained in Bureau of Mines laboratories on samples of these gasolines. Data and physical samples for the survey were submitted by 15 manufacturers on 18 grade 80, 21 grade 91/98, 22 grade 100/130, and 10 grade 115/145 aviation fuels.

Jan 1, 1948

By Thomas E. Howard

Man has been engaged in the construction of tunnels in. rock for several thousand years. During that time, methods of tunneling have changed drastically. Hordes of men chipping away at the tunnel face have been replaced by mechanical drills and explosives and by tunnel boring machines. Spoil is no longer carried on the backs of humans, but is now removed by trains, trucks or conveyor systems. These and other changes have had the effect of greatly increasing the rate of tunneling, while at the same time, greatly decreasing the potential dangers to workmen. Although the techniques, equipment and material used for tunneling are being continually improved, rock tunneling is still a slow and expensive process. Significant improvements and innovations are needed to reduce the cost and time required for tunneling if we are to fully utilize the subsurface to aid in the solution of urban problems and in the conservation of resources. This report is intended to facilitate the orderly development of tunneling technology by focusing attention on the inadequacies of rock tunneling and the improvements that are needed. The data presented were derived from the results of a comprehensive questionnaire that was completed during the summer of 1969 by more than 600 individuals and organizations in 17 countries. Table 1 lists the countries and the number of replies from each. Appendix A contains a summary profile of the national responses, while the text presents the results and a brief analysis of the conclusions that might be derived from the data in the questionnaire. The data shown in Appendix A represent the consensus opinion of each of the 17 nations without regard to the number of individual replies or the amount of tunneling activity that is represented. The national consensus was determined for each country by a plurality of the individual responses, in some cases modified by the opinion of the rapporteur. Tire above procedures can lead to situations which are misleading. For example, experience and activity arc a rational basis for analysis; but, if national replies are weighted on this basis (i.e., number of responses), informed and valuable opinion of less active countries would probably be overwhelmed and lost. In analysing the data on the basis of national responses without weighting, it becomes apparent that many of the same problems exist under a given set of conditions regardless of the number of tunnels that have been driven.

Jan 1, 1970

By E. L. Litchfield

The electrification of ammonium nitrate-fuel oil (AN-FO) blasting agents by pneumatic loaders is described and discussed. The consequences of the electrification are considered in light of the initiation requirements of electric blasting caps. It is recommended (1) that semiconductive loading tubing be utilized and (2) that the resistivity of the AN-FO be controlled; it is further recommended that the operator (3) test to assure continuity of the electric detonator legwire-bridgewire-legwire circuit prior to insertion of the cap into charge or borehole, (4) keep the legwires shunted but not otherwise connected to ground during loading of the blasting agent into the borehole, (5) assure that the borehole is discharged prior to hooking up the detonator leads, (6) assure that he is himself discharged prior to handling the detonator leads, and (7) assure that the blasting cap leads are never carried to the AN-FO loader. The basis and significance of these recommendations are explained.

Jan 1, 1968

By H. H. Dewing

The Bureau of Mines constructed a process research unit (PRU) to demonstrate new technology for extracting zinc from sphalerite concentrates. Up to 9 kg/hr of sphalerite (ZnS) concentrate was reacted at ambient pressure in the PRU with 80 pct sulfuric acid at 160° to 180° C to produce zinc sulfate and elemental sulfur. The PRU consisted of a three-stage glass reactor system: a 4-liter premix stage in which feed was slurried with 78 to 82 pct H2S04, a 40-liter stirred reactor, and a ISO-liter settling stage in which high reaction conversions were effected and excess H2S04 for recycle was separated from insoluble ZnS04 and sulfur. Evolution of sulfur-containing gases was minimized by sub-surface addition of acid feed slurry to the stirred reactor and by exclusion of air from the reactor to prevent the oxidation of elemental sulfur. Conversion of zinc to zinc sulfate averaged over 99 pct at the optimum acid concentration of 80 pct. Total sulfur losses (primarily S02) were less than 2 pct of the sulfur in the sphalerite. Elemental sulfur remained in the insoluble portion of the settled reactor product after leaching with simulated spent zinc electrolyte containing sulfuric acid. The sulfur residue contained 75 to 89 pct sulfur. Neutral zinc sulfate, required for zinc electrowinning processes, was separated from the sulfuric acid leach solution by crystallization at -15° C as zinc sulfate heptahydrate (ZnS04?7H20). The crystallization operation simultaneously effected a partial concentration of the recycled electrolyte solution by removing water.

Jan 1, 1982

By Sanford J. Douglas

This publication describes a study by the Federal Bureau of Mines of devices and methods used for testing and splicing 4,160-volt and 440-volt cables and for providing ground-fault protection for 440-volt circuits, as developed and used by the electrical staff of the Tecumseh coal mine, an open-pit operation at Boonville, Ind. The testing and ground-fault devices described should find ready application in other open-pit mines, and, with suitable modifications for voltages involved, in underground mining. The devices and testing methods are based on sound engineering principles and are time-tested and economically feasible, Four devices are used: A high-voltage tester, and a low-voltage high- current tester, both for testing 4,160-volt cables; a tester for 440-volt cables; and, electronic ground-fault protective device for 440-volt cable circuits. All the cable testers and the grounding device were designed and built at the mine from standard parts. They are inexpensive, dependable, and job tested, An attempt has been made here to describe them in enough detail so that interested persons can assemble duplicate units.

Jan 1, 1960

By J. Wade Watkins, Joseph W. Horne, Arthur Matzick

"A successful procedure for the recovery of a valuable product from weathered tank-bottom settlings has been developed in the laboratories of the Bureau of lines and used in a field pilot plant. These heavy emulsion settlings, generally regarded by the industry as waste material, have usually been drained into open pits or storage ponds and eventually destroyed.Laboratory examination of the waste material shows it to consist essentially of a ""water-in-oil"" emulsion containing a considerable volume of congealed ""paraffin."" This paraffin is mainly high-melting-point wax; known in the industry as microcrystalline wax, for which there is an increasing demand.Because of the physical properties of this wax, the tank-bottom settlings are not responsive to conventional methods used for demulsifying ordinary crude-oil emulsions.The work upon which this report is based was conducted by the Bureau of Mines in cooperation with -the Kansas State. Board of Health and with special cooperative agreements-with the Cities Service Oil Co, Bartlesville, Okla., and the Bareco Oil Co,. Barnsdall, Okla. The studies were made under the general supervision of R. A. Cattell, chief engineer, Petroleum and Natural-Gas Division, Bureau of Mines, Washington; D. C., and H. C. Fowler, supervising engineer, Petroleum Experiment Station, Bureau of Mines, Bartlesville, Okla., and under the direct supervision of Ludwig Schmidt, senior petroleum engineer, Bureau of Mines, Bartlesville, Okla.Gratefully acknowledged are the assistance and cooperation given by the Cities Service Oil Co. of Oklahoma and especially by M. J. Kirwan, manager of production, and by Q. E. Beecher, general superintendent of production, Bartlesville, Okla., and to members of their staff at Oil Hill, Kans.The assistance and suggestions of V. R. Oakley, general superintendent, E. R. Wiles, director of research, L. G. Willis, field engineer in charge crude-oil supply, and Gerald DeWalt, chief chemist, and his staff of the Bareco Oil Co., Barnsdall, Okla., were of much value in the laboratory and recovery work."

Mar 1, 1946

By J. M. Davidson

The potassium mineral polyhalite (K2SO4.MgSO4.2CaSO4.2H20) found in large deposits in western Texas and southeastern New Mexico is associated with varying amounts of halite (sodium chloride, NaCl) and anhydrite (calcium sulphate, CaSO4). Although the anhydrite, because of its low solubility and slow rate of solution, is relatively inert, the halite is dissolved immediately in any process solution with which the polyhalite comes in contact. Limited quantities of sodium chloride in the liquors used for the hot extraction of polyhalite materially improve the results obtained,4 but only a very small sodium chloride content may be desired in the entering polyhalite in other procedures, such as Bureau of Mines process 75. In. all of the processes suggested for the recovery of potassium sulphate from polyhalite the control of the sodium chloride content will be desirable, if not absolutely essential to efficient operation. OCCURRENCE OF HALITE IN POLYHALITE A preliminary estimate of the amount of halite associated with typical deposits of polyhalite may be derived from drill cores, although it should be remembered that only 50 or 60 core tests have been made in the many hundreds of square miles of the Permian basin. From a mineralogical study of 41 of these cores, Schaller and Henderson6 state: In many of the sections of core that seem when viewed by the unaided eye to consist essentially of polyhalite, both halite and anhydrite are present in greatly varying quantities - with very minor quantities of clay and magnesite.

Jan 1, 1934

By C. H. Larsen

The results of a comprehensive investigation of conveyance arrestment devices (safety catches) in United States coal mines are presented. Availability and use, performance, inspection, maintenance, testing, procedures, and regulatory requirements were investigated. Information was obtained from equipment manufacturers, mine operators, and regulatory-agency personnel, as well as from studies of domestic and foreign mining safety regulations. Traditional mine hoists and commercial elevators for mine use were investigated. Results of this and an earlier study of wire-rope practice in United States coal mines show a continued need for conveyance arrestment devices. A wide variety of these devices are in use. Only two types have been proved reliable for stopping a conveyance without injuring passengers or equipment. These are elevator overspeed-actuated wedge-clamp (Type B) safeties and broken-rope-actuated devices for wooden guides using a single-tooth-dog design developed in Ontario as a braking element. Elevators are widely used in U. S. coal mines. When maintained according to American National Standards Institute (ANSI) Specifications A17. I and A17. 2, they appear to present no major arrestment problems. Of 42 coal-mine hoists used for man transport that were inspected, 30 are in vertical and 12 in inclined shafts. Twenty-four vertical shafts use wood guides; 6 use steel. The 12 inclined-shaft systems use flanged-wheel T-rail guidance. Two wood-guided vertical-shaft systems use the single-tooth Ontario-type dog; the other 22 use multi-toothed wedges, cams, or dogs that have been proved highly unreliable. The arrestment devices in the six steel-guided vertical-shaft systems and in six of the inclined-shaft systems cannot be evaluated because performance data are lacking. The remaining six inclined-shaft systems have no arrestment devices at all. Of the 36 hoists with arrestment devices, the devices of 16 are never tested, the devices of 10 are actuated periodically with the conveyance at rest, and the devices of the other 10 are actuated periodically with a slow-moving conveyance. Although high speed is as probable as low speed in an emergency and would provide the best test of arrestment capability, no tests are performed in the United States which demonstrate the ability of an arrestment device to stop a loaded conveyance from high speed. Mine operators indicate little confidence in their conveyance arrestment devices, and manufacturers recognize a need to improve their products. Neither state nor Federal regulations provide a guide to this improvement. Mine operators, manufacturers, and state and Federal regulatory agency personnel would welcome specific guidance. In view of this, a set of application, design, actuation, stopping-performance, and testing and inspection criteria is presented as a guide to eliminating the inadequacies of these devices. Recommendations are included for improving hoist controls and machinery directly affecting conveyance safety.

Jan 1, 1972

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 A. U. Miller

"Ventilation is one of the meet important factors in mining, although until recent years less thought has probably been given to effective ventilation than to any other one phase of mining. In the past, very little, if any, attention was given air courses until they became so constricted by falls that the volume of air was greatly reduced; and, in addition, the stoppings and doors were so poorly constructed that only a very small percentage of air reached the face workings.As a matter of fact, mines have been visited where the volume of air being circulated in certain sections was much larger than in others, and where the management was striving to increase the flow of air in those sections with the least air current, believing the ventilation to be deficient. After sampling and analyzing the return air from the various sections in such mines it has been found that the quality of the air in certain places with the largest flow was more impure than in some of those with the least flow.In past years, practically all mine fans were operated by steam-driven engines supplied with steam from the mire boiler plant. No check was made on the steam consumption or the power cost of operating the fan, therefore the management had very little if any definite information as to cost of ventilating the mine.With the increased use of electrically-driven equipment in mines electricity is being used more and more to drive mine ventilating fans, and since in many instances the current is purchased from central power plants operators have come to realize that in many cases the cost of operating the fans is very high. Some engineers estimate that it ranges from 20 to 50 per cent of the total power cost of the mine. This information, together with the fact that mines are now being developed on a larger scale, requiring larger quantities of air for the men to dilute the gases liberated, has caused the large progressive companies to make, a more comprehensive study of mine ventilation, resulting in a decided improvement in the quality and quantity of air at the face workings, as well as reducing materially the ventilating costs."

Oct 1, 1930

By R. L. Marek

The number of persons fatally injured in the California petroleum industry in 1931 was 30, a decrease of 20 fatalities or 40 per cent from the number killed in 1930. As a result of the decrease in the number of fatalities for 1931, the fatality curve of tie California petroleum industry reached its lowest point in nine years. Although reductions in personnel--which permitted the retention of a select and experienced class of workmen, decreased active field-development work, and curtailed production--undoubtedly have had a marked effect on reducing the number of fatalities in 1931, the decrease also has resulted from continued accident-prevention efforts. Statistics show that a direct relationship exists between development activity and the number of men accidentally killed in the drilling and producing division of the California petroleum industry. For example, when the average number of drilling wells in 1930 was 29 per cent less than in 1929, the number of men accidentally killed at drilling wells dropped 48 per cent; and when the average number of drilling wells in 1931 decreased 52 per cent from 1930, the number of fatalities at drilling wells decreased 58 per cent. The relationship between field-development work and fatality frequency is significant because each year at least 50 per cent of all the fatalities in the California petroleum industry occur in the drilling and producing division. This relationship should serve to guide the accident-prevention efforts of the industry, especially in the drilling and producing division, toward checking an increase in fatal accidents when development activity again takes an upward trend.

Jan 1, 1932

By A. T. Iannacchione

Underground limestone mines typically use the room-and-pillar method of mining in the generally flat-lying limestone formations. In some cases the dip may exceed 5° which can result in unique roof instability problems. Stability may be further exacerbated by the presence of horizontal tectonic stresses. Field studies and numerical model analyses are combined to assess the affect of the dip in various stress conditions. The results showed that where the horizontal tectonic stresses are sufficient to cause intact rock failure, increasing dip results in increased failure potential. The effect of the dip is greater when the maximum horizontal stress is parallel to the dip. Two case studies are presented and evaluated against the findings of stress analysis results. The study showed that the empirical rules of orienting headings parallel to the maximum stress are generally applicable to dipping excavations, except when mining in the up-dip direction. The importance of accurately determining the orientation of the maximum horizontal stress is emphasized because the window of favorable orientations relative to the stress is small.

By David Bendersky

This report covers a technical and economic investigation of old electrical power systems, equipment and practices being used in the metal/non-metal raining industry. The principal sources of information were the MSHA District offices, visits to representa¬tive mines and mills, equipment manufacturers and the literature. A list of 85 mines and mills, submitted by the MSHA Districts as candidates for this study, is given and their characteristics are analysed. The electrical power systems and practices at the 10 mines and 9 mills which were visited are described. The principal areas which do not conform to standard electrical practices are discussed with emphasis on the safety aspects of these practices. The costs to update electrical power systems and practices in metal/non-metal mines and mills are given. The principal findings of the study are summarized and recommendations are submitted.

Jan 1, 1980

By Paul S. Goodman

Volume II The purpose of this study is to explain reasons for the productivity differences in mining crews. The literature on group productivity is examined. Then a new approach to estimating productivity differences is proposed and estimated across seven different mines. The results indicate a fairly robust model in terms of explanatory power. Recommendations on how the model can be used as a managerial tool are presented.

Jan 1, 1985

By R. W. Stahl

Burning coal-mine refuse banks were surveyed in 15 States. The following characteristics were tabulated for 495 hanks: County; name, population, and distance of nearest town; size and status of bank; status and stage of fire; and topography. Ways of controlling fires were reviewed, the compacting and sealing method proving most satisfactory. Means for preventing refuse-bank fires by proper construction of banks are described.

Jan 1, 1964