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By Michael R. Norland

Surface and subsurface stabilization of mining-related wastes through revegetation depends upon the physical, chemical, and biological condition of the waste following mining. Mining disturbances can significantly alter the soil physical, chemical, and biological characteristics of a site, reducing or eliminating mycorrhizal fungi from the soil. Mycorrhizae are economically and ecologically important because they can alleviate environmental stresses caused by lack of proper soil condition and because they are vital to stabilization of mining waste by increasing plant survival and biomass through increased nutrient and water uptake. This report discusses some of the ecological factors that may affect mycorrhizae-plant associations on mining-related wastes and provides general information on mycorrhizae inoculation technology.

Jan 1, 1993

By Ann G. Kim

The U.S. Bureau of Mines applied its mine fire diagnostic method to an abandoned anthracite mine fire site in Carbondale, Lackawanna County, P A. The technique to locate fires in abandoned coal mines and coal refuse piles includes the determination of hydrocarbon concentrations in mine gases, the imposition of an underground gas flow direction, and use of a surface mapping method, to define heated and cold zones in underground coal strata. The heated zones at Carbondale were characterized by elevated methane concentrations. The results of 25 communication tests were analyzed to define 2 large (approximately 100 by 250 ft) and 5 small, isolated heated zones. An approximate correlation existed between the location of the heated zones and areas of anomalous snow melt. The correlation between the results of the diagnostic? test and subsurface temperatures was not significant.

Jan 1, 2010

The Bureau of Mines, through its Minerals Availability Program (MAP), investigates the mineral supply potential of the United States and market economy countries (MEC's) for a number of minerals considered essential to the U.S. industrial base. Major activities include identification of important mines and mineral deposits, estimation of their mineral resources and production costs, and availability and sensitivity analyses. Products include data print-outs of geological and engineering information, discounted- cash-flow rate of return (DCFROR) analyses of individual mining operations, commodity availability appraisals, and analytic services to Government agencies. These products are used in assessing the mineral supply position of the United States: in setting priorities for research aimed at reducing production costs and minimizing adverse environ- mental impacts and regulatory compliance costs of mining and mineral processing operations; and in formulating and evaluating Government policies that affect minerals. Bureau MAP data and analyses have been provided to the executive and legislative branches to aid in consideration of trade, tax, and stockpile policy issues. A study of the economic potential of selected seabed mineral resources supports the regulatory responsibilities of the Department of the Interior in the U.S. Exclusive Economic Zone. Analytic studies of mineral project viability, industry competitiveness, and import dependencies were also undertaken for, or in cooperation with, U.S. and foreign government agencies, industry and trade organizations, and international lending institutions.

Jan 1, 1987

Operator efficiency and control capability along with cost effectiveness have been the quest of mining, industrial, and mobile hydraulic engineers for years. The majority of the functions in present day fluid power systems are controlled by on/off control valves. They are inexpensive and provide easy installation and operation, but they lack the quality of fine control of load flow or what is sometimes known as "feathering the load". An alternate approach to obtaining this capability is the use of electro-hydraulic servo-valves, but their implementation into a system is complex, and they are expensive. As a result, electrohydraulic systems are still used primarily in the aerospace industry. Of late, a compromise seems to have evolved between the on/ off control systems and the servo-technology is the so-called proportional flow control valves. A proportional flow control valve meters fluid to the load in proportion to the input command from the operator. In principle, it is similar to a conventional flow control valve and is tailored to meet the control requirements from the load point of view. The hydraulic system using this valve usually works in an open-loop mode with the operator closing the loop. Incorporating load-sensing mechanisms and adoption of electrical/electronic signalling into the valve make it the "ideal valve" which designers have been looking for from a techno-economic point of view.

Jan 1, 1983

By J. B. Zadra

The use of activated carbon for extracting gold and silver from pregnant cyanide solution and pulp has been investigated many times. The primary advantage of this use of activated carbon is that .the dissolved values can be recovered from slimy ore pulps or from slime portions of ore without settling and thickening or filtering. The loaded carbon is removed from the barren pulp, and the pulp can then be discarded. Activated carbon has been used recently in treating gold ores containing very little soluble silver. When the carbon was loaded with a suitable amount of gold, the silver load was negligible. The remaining problems concerned the removal of the gold from the carbon, the recovery of the gold as bullion, and the reuse of the unloaded carbon. As described in a recent report, a method that solved these problems was developed. The gold-laden carbon was leached with caustic sodium sulfide solution and the gold simultaneously recovered by electrolysis. Both the carbon and the spent solution can be reused. That process was applicable to gold-laden carbon only. It was not applicable to carbon carrying silver, because sodium sulfide does not leach silver from carbon but "fixes" it. It has been necessary, therefore, to develop a modified process for the removal or desorption of both gold and silver from loaded carbon. This modi¬fied process permits the use of activated carbon for extracting both gold and silver from gold ores carrying enough silver to have economical interest or in which silver may be the predominating value.

Jan 1, 1952

By E. G. Davis

As a result of interest by the U.S. Department of Energy, the Bureau of Mines conducted studies on comminution of bituminous coal to the 2-um particle size range using the Bureau-developed turbomill. Both "plant grind" size (80 pct minus 75 um) and microsize (minus 10 um) coal can be produced in a single step with the Bureau's turbomill. In 15 min, minus 2.4-mm coal milled in water with steel shot was reduced tc 65 pct minus 75 m and 26 pct minus 2 m, with an energy requirement of 139 kW^h/mt coal. Plant-grind size coal milled in water, with Ottawa sand as the milling medium, was reduced to more than 45 pct minus 2 m in 15 min, at 175 kW?h/mt. Plant-grind coal milled with steel shot was reduced to 57 pct minus 2 um in 15 min, at 138 kW?h/mt. When diesel fuel was substituted for water, the milling of the coal was less effective and less energy efficient. Keeping the pulp dispersed was critical. Without an effective dispersant, the slurry became very viscous with increased milling time, resulting in higher energy requirements, low heat dissipation, and poor grinding efficiency.

Jan 1, 1987

By J. W. Thompson

LIMESTONE DEPOSITS. Limestone deposits that have not been demonstrated to be of such quality as to give them any substantial value over other limestone deposits of the same region, are not regarded as minerals. Gray Trust Co., In re, 47 Land Decisions 18, p. 20. OIL AS A MINERAL. Oil is a mineral substance and its removal will greatly impair the value of the land from which it is removed. Texas & Pacific Coal & Oil Co. v. Howard. Southwestern 735, p. 737. Tex. Clv. App. 212 OIL AND GAS AS MINERALS OWNERSHIP. Oil and gas are minerals and so long as they remain in place they belong to the owner of the land under which they are found and such owner has the right to explore for the oil and gas on or under his land and when found to remove and possess the same. Kimbley v. Luckey, Okla. - 179 Pacific 928, p. 831. OWNERSHIP OF MINERALS LACHES NO BAR. The owner of minerals in land can not be barred by laches for failing to assert his ownership where his title had not been ques- tioned and his right invaded. No lapse of time bars one's right to property and it is only in case his right has been invaded that it can be barred by laches.

Jan 1, 1920

By Dennis A. Hansen

As part of a U.S. Bureau of Mines program to develop a more continuous titanium metal extraction process that uses domestic resources, a study was made to determine the extraction of titanium (Ti) and iron (Fe) from New York rock ilmenite using fluosilicic acid (H2SiF6). The effects of leach temperature, acid concentration, and particle size were investigated for the rate at which Ti and Fe are extracted from the ilmenite. Within the leach time studied, the extraction data fit a shrinking-core model; the rate-controlling step was diffusion of H2SiF6 through an ash layer resulting from a heterogeneous leaching reaction. The rate is linearly dependent on the H2SiF6 concentration and is inversely proportional to the square of the particle diameter. Using 2.6M H2SiF6 at 85°C, 49% of the Ti and 53% of the Fe in 44-to 74-µm New York rock ilmenite were extracted in 3 h.

Jan 1, 2010

By Floyd R. Hertweck

This Bureau of Mines publication contains analyses and related source data for 349 natural gas samples from 26 States and 2 foreign countries. The 3 samples from foreign countries and 339 of the U.S. samples were collected during calendar year 1983. The remaining seven samples were collected earlier, but releases granting permission to publish were not received until 1983. All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by the mass spectrometer and chromatograph. The results of these investigations are published annually to make the information available to the petroleum industry and the general public. Twenty-seven publications have presented the results of 13,332 gas analyses made prior to 1983. The first three bulletins (1-3)3 contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960; these bulletins have been supplemented annually by information circulars (4-17, 19-24, 26-27) containing 8,104 analyses of sam¬ples collected since 1960.

Jan 1, 1984

By Louis R. Iverson

Patterns of species colonization, biochemical interaction among species, and competitive phenomena were studied in four reclaimed areas in western North Dakota ranging in age from one to four years after mining, along with a site from a native mixed grass prairie for comparison. Early successional changes in floristic composition and soil chemistry were quantified. The mined sites had been contoured, topsoiled, fertilized and seeded. Despite seeding of agronomic species, initial colonization was by fugitive species; analysis of the seed bank in topsoil showed that the most dominant colonizers immigrate after topsoiling. Of the 95 species encountered, Kuchia scoparia was the most dominant in the first two years following mining. Kochlo had relatively low densities in the first year (50-80 plants m-2), but was robust and attained heights of 88 cm with a biomass of about 400 g m-2 In the second year, the plant densities increased to over 10,000 plants m"2 but the height and biomass were reduced to 15 cm and 90 g m-2. However, during the third and fourth years Kochia density declined and was practically non-existent by the fourth year, while the planted Agropyron grasses had concomitantly increased. Other pioneers like Amaran thus retroflexus, Chenopodlum album, Helianthus annuus, Salsola spp. And Setaria spp. showed a less abrupt but similar decline. Chemical analysis of the soils over the same time period showed decreases in electrical conductivity (E.C.), and in the concentrations of P, Ca, Mg, Na, Li, Sr, and SO4 (due to leaching), while N increased. Field studies were conducted on the competitive relations between the dominant species - Kochia scoparia and Agropyron spp. - during early succession. It was found the Kochia acted as a "nurse" crop for several months during the first year of Agropyron spp. establishment, but then began to shade heavily by late July, thus reducing grass tillering. Field and growth chamber experiments on the intraspecific competition relations of Kochia demonstrated that its density and dry matter production, per plant and per unit area, conformed to several laws of plant population biology. Autotoxicity or the depression in growth of a species by its own degradation compounds, in Kochia, appears to be the main factor causing the decline in its growth. Results from a field experiment indicated that thinning dense second year Kochia stands to the density of first year stands did not alter the growth of Kochia, providing strong evidence for autotoxicity. Similarly, several growth chamber experiments demonstrated that small amounts of decaying Kochia leaves and especially roots were toxic to Kochia growth, but not Melilotus officinalis or Agropyron canlnum, Chemical analysis of the soils and plant tissues indicated nutritional im¬balances as shown by P/Mn and P/Zn ratios may be responsible for autotoxicity. In addition to Kochia, a bioassay experiment showed allelochemics to be important in several other colonizing species. Although our results indicate that later stage species generally have greater toxicities than first year colonizers, autotoxicity in the very initial stages seems to be accentuated by harsh habitat conditions. Several practices (mowing. fire, etc.) are used to manage grasslands. Mowing of the first year erect, annual, colonizing vegetation was shown to be beneficial in the growth and establishment of wheatgrasses after mining in western North Dakota. Plots containing Kochio predominantly were mowed in mid-and late-July, and in mid-August, during the first year of growth after recontouring, replacing topsoil. seeding and fertilizing. It was found the Kochia densities were reduced to two percent of the control and its biomass reduced to less than one-third when the area was mowed in mid-August. On the other hand, wheatgrasses showed increases of 23% in stem density and 860% in biomass production over the controls when mowed in mid-August. The mowing of Kochia just before seed-set apparently reduces interspecific competition between Kochia and Agropyron spp. during the following growing season. The method is highly recommended for use in hastening the establishment of planted grasses.

Jan 1, 1982

By S. M. Shelton, W. A. Calhoun, M. M. Fine, T. L. Johnston

"FOREWORDFerrograde manganese ore or its equivalent is essential to the manufacture of every ton of steel produced; although it is well known that there are large deposits of low-grade are in the United States, the production of substantial amounts of ferrograde material from domestic sources presents a problem that becomes more and more critical as the stockpiled ore depleted through inability to procure adequate supplies from foreign sources. Consequently, a program of laboratory,and pilot-plant investigation designed to solve the problem of obtaining a domestic supply of manganese has been undertaken by the Metallurgical Division, Bureau of Mines.This paper is one of a new series that include reports of results obtained in the various investigations conducted under the manganese program. The scope of the program and the organization that was set up to direct and supervise the were discussed in the foreword of the first paper of this series, Report of Investigations 3606 Manganese Investigations. 1. Concentration of Manganese Ores,from the Drum Mountain District, Utah, by S. R. J. D. Vincent, and C. R. Schack. Other reports will be published as the work progresses."

Mar 1, 1942

By Shelby Z. Palya

"INTRODUCTION The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mining substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes reports and articles published during the period January 1, 1975, to December 31, 1979. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960; 2 the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960; 3 the 5-year lists of publicatioll3 and articles, from January 1, 1960, to December 31, 1964,4 from January 1, 1965, to December 31, 1969,5 and from January 1, 1970, to December 31, 1974; 6 and the annual lists of Bureau publications and articles from January 1 to December 31, 1975,7 from January 1 to December 31, 1976,8 from January 1 to December 31, 1977,9 and from January 1 to December 31, 1978.10"

Jan 1, 1980

By William D. Dodge

A typical quality program plan is presented for explosion-proof (XP) electrical enclosures. The plan is suggested for manufactures of XP enclosures which are to be certified by MSHA for mining use. The plan describes the quality system, organization and implementing mechanisms which are to be applied in the manufacture and delivery of certified XP enclosures. Example forms and example procedures are included.

Jan 1, 1984

By P. L. Swanson, F. M. Boler

The U.S. Bureau of Mimes conducts research at the Galena Mine, Wallace, ID, with the aim of mitigating the effects of rock bursting. Destress blasting is commonly used as a stress control technique at the mine. A digital seismic array and an array of borehole pressure cells (BPC's) had been installed near the site of a stope undergoing mining and periodic destressing. The instrumentation was being monitored at the time of a destress blast of the 46-99 stope. No significant seismic events occurred coincident with the destress. However, the destress was followed by a 21/2-week period of increased seismic activity, including two damaging events on February 7, 1990, at 034500 (hour, minute, and second) and 122020 Pacific standard time. BPC measurements indicated coseismic ground pressure changes on the order of 200 to 300 kPa associated with the damaging events. Fault plane solutions and dislocation models established that stress changes induced by the event at 034500 may have been significant in promoting the occurrence of the event at 122020. Theoretical investigations suggest that applying knowledge of the existing stress field, an understanding of rock burst mechanics, and fracture mechanics principles can improve destress effectiveness.

Jan 1, 1993

By S. A. N. Sheya

The U.S. Bureau of Mines performed batch equilibrium contact experiments to examine the ability of activated coconut-shell carbon to adsorb various metal cyanide complexes. Tests were also conducted to determine the effect these cyanide complex impurities might have on the adsorption of gold by the activated carbon. Metal cyanide species included in the investigation were antimony, arsenic, cadmium, calcium, cobalt, gold, iron, mercury, nickel, silver, thallium, and zinc. Tests were made over a pH range of 6.4 to 12.5. The carbon exhibited a preference for gold adsorption over other metals present in solution. In the absence of gold, the metal cyanide complexes were adsorbed; adsorption generally decreased with increasing pH. However, calcium and thallium adsorptions increased with increasing pH, while arsenic and iron were not adsorbed at any pH.

Jan 1, 1989

[This Report represents the culmination of work perfomed under Contract No. .,JG1551A8 for the U.S. Bureau of Mine.The &apos;.:o-< embeded a site evaluation, engineering E:-y- ,, esign, and preparation of specifications for construction of a Transport Research 7 :4 (HTRF)The HTRF is designed as a research facility J evaluate the hydraulic transport of large lump coal at a prototype ;e scale. The HTRF is to be constructed and operated by the Pittsburgh and Safety Research Center of ;. re U.-AN a*, their Bruceton, Pennsylvania test center. In terms of technical capability, the HTRF will have transport pipeline:: of -, twelve-, and eighteen-inch diameter _&apos; with supporting coal handling n , water forage a.^ &apos;d conveyance, mixing, pumping, and dewatering equipment, plus instrumentation and controls. Maximum design velocity 13 20 ft/sec.; solids concentration, by, volume, will; 1 be a maximum-- of sixty, percent. Each test loop is designed to accommodate solids of up to one-third the diameter e - of the pine. The Final Report Pr.-&apos;I-rents information of t HTHF,. including the site evaluation, design criteria, a description of the a description of the procedure to be used for operation of the facility, an estimate of the cost to construct the f^Cilit:r, 1 p el_~lli.&apos;iU construe`, icn Schedule, and a construction suicJ_iicaT.l_ccn&apos;. T e c011SLr?Jc&apos;.ion soecl_ i.on _ccnta_i:s technic.&apos;..i re7,uir: (-n`,s for !&apos;urr1S~ &apos;~latcr..al. and ec-uipr,ent for :":C1 C_`:_C ti on of ti,_ H ice&apos; u:&apos;.:i ._II u s(-.6 for ~.Iir: .3!7 soliciting bids. `.l_o included n cc&apos;;,art_- c?r~.air sV:et..: :s ^nd rr^.?]

Jan 1, 1976

The wealth of a nation may be measured in many ways, but one of the most important is its natural resources, particularly its minerals. Minerals create the wealth upon which economic prosperity and defense preparedness rest. Managing mineral resources for the benefit of all Americans continues to be an important national goal. In its 78-year history the U.S. Bureau of Mines has established itself as the world&apos;s premier mineral information and research agency. Its authoritative, comprehensive data and pioneering research have contributed significantly to a strong U. S. mineral position in the world.

Jan 1, 1988

By Julie N. Walker

This U.S. Bureau of Mines report reviews the first 2 years of the agency&apos;s progress in implementing total quality management (TQM), which the agency refers to as Quality Improvement (QI). All employees have been trained in basic TQM concepts, a cadre of facilitators has been selected and trained, and 13 Bureauwide teams are addressing specific issues that were identified by Bureau employees nationwide as problem areas. Also in place are a Quality Council composed of the Bureau&apos;s top executives, a Quality Management Board, and eight QI Working Groups to provide a national 01 infrastructure. There are also Quality Steering Groups at each Bureau location nationwide to address local concerns. In addition to the narrative text, the texts of salient memoranda and other documents are included as appendixes.

Jan 1, 1992

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963