Search Documents

Case studies from four western states are used to illustrate the impact of the environmental compliance process on the mining industry. The case studies were not chosen as a statistically significant sample of all mining operations in the western United States but were chosen as representative of operations on both public and private lands and in locations that exhibited varying degrees of involvement by governmental units, non-governmental organizations and the general public. Basically, each case study was chosen because some aspect of their environmental compliance process helped to illustrate an interesting point in the regulatory process. The criteria used to select the case studies were: mines located in different jurisdictional areas, mines located in varying geological areas~ mines located in areas having different historical relationships with mining: and operations that are in production as well as those seeking an operating permit. The variety of such projects should provide the necessary foundation to evaluate the impacts of the environmental compliance process in each location.

Jan 1, 1994

By Robert W. Smith

The Bureau of Mines is engaged in a systematic evaluation of the thermodynamic properties of combustion gases. These studies are designed to provide basic thermodynamic information of high accuracy, facilitating the theoretical study of flame and combustion phenomena. This report is the fourth of a series4/ presenting results of the study for particular fuel-oxidant systems. These calculations have as their objective the evaluation of the constant pressure flame temperatures of methane-air, propane-air, and ethylene-air mixtures for a range of pressures.

Jan 1, 1953

By Lewis A. Smith

This circular presents a summary of the domestic chromium industry, and discusses the salient features of the world situation , reflecting the literature of the subject . The United States Bureau of Mines has in its files additional detailed information on many subjects briefly discussed in this paper and desires to assist the industries and the public by giving further data in response to individual inquiries . It will welcome comment and criticism and any contributions that would assist in making future editions of this circular more accurate . Unlike most common metals , chromium is rarely marketed as a pure metal . The chromium industry deals mainly with chromite , the principal ore of chromium , and with ferrochromium , the basic alloy in which chromium enters the metallurgical industry.

Apr 1, 1932

By Jay F. Colinet

Respirable dust exposure has long been known to be a serious health threat to workers in many industries. In coal mining, overexposure to respirable coal mine dust can lead to coal workers? pneumoconiosis (CWP). CWP is a lung disease that can be disabling and fatal in its most severe form. In addition, miners can be exposed to high levels of respirable silica dust, which can cause silicosis, another disabling and/or fatal lung disease. Once contracted, there is no cure for CWP or silicosis. The goal, therefore, is to limit worker exposure to respirable dust to prevent development of these diseases. The passage of the Federal Coal Mine Health and Safety Act of 1969 established respirable dust exposure limits, dust sampling requirements for inspectors and mine operators, a voluntary x-ray surveillance program to identify CWP in underground coal miners, and a benefits program to provide compensation to affected workers and their families. The tremen­dous human and financial costs resulting from CWP and silicosis in the U.S. underground coal mine workforce are shown by the following statistics: ? During 1970?2004, CWP was a direct or contributing cause of 69,377 deaths of U.S. underground coal mine workers. ? During 1980?2005, over $39 billion in CWP benefits were paid to underground coal miners and their families. ? Recent x-ray surveillance data for 2000?2006 show an increase in CWP cases. Nearly 8% of examined underground coal miners with 25 or more years of experience were diagnosed with CWP. ? ?Continuous miner operator? is the most frequently listed occupation on death certificates that record silicosis as the cause of death.

Jan 1, 2010

By Thomas J. Peters

During the 1982 Bureau of Mines study, 55 lode and 17 placer claims were held in the RARE II area. An estimated 150 lode claims and 50 placer claim, have been located in the study area; five were patented. There are no mineral leases. Gold has been produced from 8 lode mines and stream gravels have been worked for placer gold at 4 sites. Two suction dredges were active in stream gravels, but no significant gravel bars are identified. Identified mineral resources in the Weaver Bally area are gold and byproduct silver. The identified resources are at the Globe Mine, where approximately 33,000 tons of indicated marginal reserves (2,000 tons in the RARE II area, and 31,000 tons in the adjacent proposed Trinity Alps Wilderness) contain 0.45 oz gold per ton and probably 0.1 oz silver per ton. There are an additional 150,000 tons of inferred marginal reserves (35,000 tons in the RARE II area, and 115,000 tons in the adjacent proposed wilderness) averaging 0.38 oz gold per ton and probably 0.1 oz silver per ton. There is high potential for additional resources at the Globe Mine.

Jan 1, 1983

By R. B. McElwaine

From November 1943 to April 1944, the Bureau of Mines put down 18 churn-drill holes aggregating 2,571 feet of bore in an investigation of the virtually abandoned zinc deposits of the north-central Arkansas district, principally in Marion, Boone, Searcy, and Newton Counties. The ore of this area occurs in flat-lying sedimentaries of the Mississippian and Ordovician ages. Much of the zinc is in the form of carbonate and silicate, although some sulfide has been produced. Preliminary studies resulted in selection for investigation of the Big Hurricane mine in northwest Searcy County, the Spies mine in northeast Newton County, and the Coon Hollow mine in eastern Boone County The comparatively large production of th.ese properties in the past was a factor in the selection. This report describes the work accomplished in the investigation and presents the data obtained.

Jan 1, 1948

By H. D. Hess, C. P. Mabie

This report describes in detail the results of petrographic research conducted on 21 phosphate ores representing important deposits in southwestern Montana , southeastern Idaho , and northeastern Utah . The ores are described and categorized by mineralogical and chemical composition , thermal behavior of organic carbon , and textural constitution . Descriptive and genetic classification schemes applicable to western phosphate ores are discussed ; results from related studies made of the collophane mineralogy are also presented . The latter studies were centered on determining unit - cell dimensions and CO₂ , P2O5 , and fluorine content of collophane concentrates of 11 high - grade phosphate- rock hand specimens selected solely for this purpose . On the basis of this investigation , operational methods have been developed for quantitatively describing textural and compositional features that are likely to be significant in determining the response of phosphate ores to conventional beneficiation treatments ; systems for classifying the ores in relation to these features have been proposed . Studies to date point out distinct textural and compositional variations in the western phosphates and illustrate their importance in determining optimum beneficiation procedure .

Jan 1, 1964

By Albert J. Forney

Extensive studies have been made of the various effluents found in the Synthane coal-to-gas process. Analyses have been made of the waters, gases, and trace elements present in some of the streams. Results of analyses show the water effluents are the area where extensive research is needed.

Jan 1, 1974

By Michael S. Wieland

This report investigates whether it is tractable and thereupon reasonable to remove the booster influences when ranking the toxic fumes of non-cap-sensitive mining explosives. The hazard potential is represented by relative fume toxicity RFT, the resultant influence computed from a formulated rule with a restricted set (tally) of fume components and multiplying constants. The RFT result is compared to the rule criterion that represents the worst case tolerable toxicity stipulated by regulations or otherwise. The typical nonstoichiometric booster composition can render notable unwanted influence on the RFT ranking results. Historically, the remedy was to shoot the booster separately and reduce the trial concentrations by the relevant subtractions. Unreal negative concentration results were noted on rare occasions, revealing the faulty nature of the reduction procedure. With thermodynamic reaction chemistry codes TDRC, on the other hand, the booster ingredients can be retained in or removed from the reactant tabulation, yielding reduction factors taken as the concentration ratios for the two circumstances. The underlying presumption regarding reduction factors is that the ratios of component concentrations with and without the booster ingredients when resolved theoretically ought to equal those rendered experimentally, when tractable. Upon rearranging the presumed relationship, the unadjusted fume concentrations divided by theoretical reduction factors yield the wanted readjusted fume concentrations, thereby removing the booster influence without generating unreal negative concentrations. The work principle from thermodynamics restricted by the constraint of zero-net interaction loss is utilized in conjunction with the TDRC to resolve the wanted (Z-state) fume spectrum. This circumvents the recognized difficulty with traditional hydrodynamic detonation theory that is related to the nonideal reaction characteristics of typical mining explosives. The tacit characteristic of the Z-state resolved from the non-trajectory work principle is that it can not be remedied or tampered with, unlike the traditional trajectory techniques where the reaction products can be readjusted by changing formula representations, nullifying specific reactions or otherwise manipulating the thermodynamic trajectory process. Though the work principle theory is an unfinished formulation, the Z-state results prove worthy enough for rendering trends and comparisons and reaching otherwise useful conclusions. Further refinements should yield more reliable fume spectra and indicate explosive composition readjustments that would reduce toxic effects within underground mines and the wider world environment.

By Alla D. Mah

Compilation of data on materials of metallurgical interest is one of the important activities of the Berkeley Thermodynamics Laboratory of the Bureau of Mines. Recent renewed interest in metallurgy of vanadium renders the present compilation a timely guide for experimentation to improve present methods or to develop better methods of extractive metallurgy. Thermodynamic data for vanadium and its inorganic compounds have been critically surveyed, selected, and compiled into one convenient reference from which information can be readily obtained for evaluating heat balances, determining trends, and establishing limits of metallurgical processes. By indicating the direction of experimentation, this report enables the saving of time, effort, and expense which would otherwise be necessary for trial and error experimentation. Much of the data has been obtained experimentally at the Berkeley laboratory. Other data were collected through an extensive survey of worldwide literature through April 1965. Estimates were made when no data were avail-able. Data on the vanadium halides was sparse, and the results derived from existing data were at times divergent. Some of the selected values for the halides may need modification as more or better experimental data become available.

Jan 1, 1966

By W. W. Agey

An inexpensive technique that laboratory studies indicated would significantly reduce seepage in irrigation canals was devised and tested through research sponsored by the Bureau of Reclamation and the Missouri River Basin Field Committee. Laboratory tests simulating optimum field conditions determined that easily applied sodium carbonate solutions made test beds of canal lining materials virtually impermeable for long periods. The study comprised alternative laboratory treatments of 3-inch-deep test beds of canal earths with 74 water-soluble chemicals in search of one 01' more that would effectively improve the water barrier characteristics of the component clays. Sodium carbonate, one of the least expensive, was among the most effective. The addition of 0,4 lb of reagent per sq yd greatly reduced the seepage from typical, highly permeable test beds. The reagent penetrated and sealed surface for about a 1.5-inch depth.

Jan 1, 1965

By Robert L. Mentch

CADMIUM is one of the metals apparently destined to remain relatively scarce. The en tire supply of primary cadmium is recovered as a byproduct, concurrently with the treatment of ores of other metals. Development of the cadmium industry is attributed to metallurgical improvements in the zinc industry; output depends almost wholly upon zinc production. Cadmium is a metal of specialized uses where its superior performance has developed a strong, expanding demand. The supply, however, has been relatively unresponsive to price because of its byproduct nature. Cadmium's outstanding properties would assure it a manyfold greater market if more were available at lower prices.

Jan 1, 1958

By H. C. Fuller

Submerged combustion and inverse solubility methods were investigated as promising alternative means for crystallizing manganese sulfate from solutions produced by leaching manganese ores with either sulfuric acid or sulfur dioxide. Evaporation of water from typical manganese sulfate solutions by sub-merged combustion techniques enabled production of a slurry containing 32 to 39 pct MnSO4.H2O crystals suspended in a saturated solution of manganese sulfate. Such a slurry required further processing by thickening or filtration and drying to produce crystals of MnSO4.H2O. In a second approach, semicontinuous processing of manganese sulfate solu¬tions by thermal crystallization under pressure effected a recovery of 94.5 pct of the MnSO4.H2O as dry free-flowing crystals. Treatment of a solution containing about 100 grams manganese per liter at 189° C, produced a "barren" solution containing only 1.9 grams manganese per liter. Calculations made on comparable manganese sulfate solutions show that the heat requirement of the thermal crystallization method was about one-third to one-fourth that of the submerged combustion method.

Jan 1, 1966

By H. W. Davis, W. W. Adams, O. E. Kiessling

"Current economic problems frequently have focused attention upon the lack of adequate quantitative information indicating the relationship between human effort and output in various branches of the mineral industry. With the exception of complete records covering coal mining, only scattered information on the units of human energy required to produce a unit of raw material is available for most of the important industrial minerals. Fortunately a virtually complete statistical record is available covering this phase of the iron-ore mining industry.For many years iron-ore mining companies, whose interest in safety work is well-known, have reported annual data on employment to be used in the compilation of accident statistics. These data on hours of labor and other detailed employment information have been correlated with the statistics on production also reported annually by producers. The outstanding trends shown by this composite record for the 10-year period 1923-32 are included in the following discussion, supplemented by a summary table that presents the principal statistical background of the study. 5The substantial reduction in the number of men needed to produce the annual iron-ore requirements of the United States, as shown strikingly in the graphs, illustrates that in iron-ore production improvements in technology have been consistently winning a battle over the difficulties of nature. In 1923, for example, 41,294 men working 107,551,244 hours were required to produce 69,351,442 gross tons of merchantable ore, equivalent to an average output of 0.645 ton per man-hour. In 1929, however, only 30,763 men working 77,111,686 hours 'zero required to produce 73,027,720 tons of merchantable ore, equivalent to an average output of 0.947 ton per man-hour. Thus, from 1923 to 1929 the average number of men working decreased 25.5 percent and the total man-hours worked 28.3 percent, while the average output per man-hour increased 46.8 percent and total merchantable ore production 5.3 percent."

Feb 1, 1935

By Jack E. Fraley

In this Bureau of Mines study, sealants containing mineral wool, cement, etc, were sprayed through dry-process equipment that propels dry material pneumatically to the water-adding nozzle. Advantages over slurry applications include no mixing, no extensive cleanup, and freedom from hardened cement in equipment should power be lost. Sealants with large mineral wool nodules (>l-inch) were sprayable at rates to 900 square feet per hour for 1/2-inch thickness with little dust and smooth material flow through equipment, but they were weak for mine use, Materials containing small wool nodules (1/4-inch) were stronger but tended to plug lines because the nodules were inadequately separated in the shredder. Increasing the dedusting oil also increased line plugging by holding the nodules together in larger lumps. Best results were obtained using a 3/4-inch-nodule wool with cement binder, which provided both smooth flow through the machine and adequate strength.

Jan 1, 1977

By Dennis A. Hansen

The solubility of anhydrous aluminum chloride in solutions of titanium tetrachloride and vanadium tetrachloride was determined as part of a re-search project-by the Bureau of Mines to make a homogeneous alloy sponge of titanium, vanadium, and aluminum. Solubility curves were established using an autoclave at 75°, 100°, 125°, and 150° C. The solubility of AJC13 in TiC14 is 0.2 wt pct at 75° C; it increases to 18.3 wt pct at 150° C. The data concur with data from earlier researchers of this bi-nary system for 75° to 125° C. For the VC14-AlC13 binary system the solubility of AlC13 is 0.1 wt pct at 75° C, increasing to 1.6 wt pct at 150° C. For the TiC14-AlClrVC14 ternary system the solubility of AlC13 decreases from the values found with a pure TiC14-AlC13 system to the lower values found with a pure VC14-AlC13 system at the respective temperatures.

Jan 1, 1986

By John D. Foulkes, David A. Curtis, Robert L. Lagace, John L. Rothery

An investigation is made of the feasibility of developing compact transmit antennas and/or other means to efficiently couple VLF to MF band radio energy between portable wireless communication units in coal mines. The completely wireless communication ranges between two portable radios equipped with practically-sized reference loop antennas in representative coal mine environments are estimated. Antenna technology is assessed with respect to transmit moment, range, intrinsic safety, battery and wearability requirements to deter- mine the most suitable antenna types for use by miners. It is concluded that air-core bandolier loop antennas, and perhaps ferrite-loaded loop antennas, having peak transmit moments of about 2.5 ampere-m5 will be the most effective antenna choices for portable units. This choice, however, will not allow the range goal of 1350 feet to be attained in mines having unfavorable signal attenuation and noise environments. Rectangular air-core loops are compared with grounded horizontal-wire and vertical-wire mode exciters for fixed station applications. The potential for significantly increasing the wireless communication range by inductively coupling to communications and power lines in a mine is evaluated and found to be considerable based on theoretical coupling equations. Lastly, the theoretical performance of a hybrid noise cancelling diversity receiving technique that utilizes both the electric and magnetic field components of the ambient noise to improve the receiver output signal-to-noise ratio under certain adverse conditions is estimated and shown to be favorable when the magnetic and electric field noise components are highly correlated.

Jan 1, 1977

By L. C. IlsLey

From time to time the Bureau of Mines has issued publications dealing with the various classes of explosion-proof mining machinery that have been tested and approved as permissible for use in mines having atmospheres that may become inflammable by reason of the inadvertent presence of gas or dust. These publications are confined almost entirely to description of the features contributing directly or indirectly to the prevention of explosion or shock hazards, and are intended to give inspectors, safety engineers, and others already familiar with the general safety requirements more detailed information on the safety features of the design of a particular machine. As a background for papers describing permissible machines and to avoid the necessity of duplicating descriptions of methods of conducting investigations and tests of such machinery, Bureau of Mines Bulletin 305, Inspection and Testing of Mine-Type Electrical Equipment for Permissibility, was published in 1929. Three bulletins giving detailed descriptions of the three most numerous types of machines have been issued, viz., Bulletin 313, Permissible Storage-Battery Locomotive and power Trucks. Bulletin 343, Permissible Coal-Handling Equipment. Bulletin 382, Permissible Coal-Cutting Equipment.

Jan 1, 1937

By M. Kanda, W. D. Bensema, J. W. Adams

Two different techniques were used to make measurements of the absolute value of electromagnetic noise in and above an operating coal mine, McElroy Mine, located near Moundsville, Nest Virginia. The electromagnetic environment created by 300 volt dc and 480 volt ac machinery was measured. In one technique noise was measured over the entire electromagnetic spectrum of interest for brief time periods. The noise was recorded using broadband analog magnetic tape. The noise data was later transformed to give spectral plots. In the other technique, noise amplitudes were recorded at several discrete frequencies for a sufficient length of time to provide amplitude probability distributions. The specific, measured results are given in a number of spectral plots and amplitude probability distribution plots.

Jan 6, 1974

By D. E. Wolfson

As part of its overall program of coal-carbonization research, the Bureau of Mines is studying the coking properties of coals from various fields of this country. Few of the coals included in this survey are used for the manufacture of metallurgical coke, although some well-known coking coals necessarily are tested to provide comparative data, particularly on blending properties. The overall objectives of the study were given in detail in a previous report.3/ The inherent suitability of coal for metallurgical purposes, as distinguished from economic considerations, depends primarily on (1) the available reserves, (2) chemical composition, (3) preparation characteristics, and (4) carbonization behavior. These items are considered in selecting coal for carbonization tests.

Jan 1, 1956