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By Chas. F. Jackson

The annual reports of the supervising engineers of the seven sections comprising the Mining Division are assembled in the following pages and constitute the annual report of the division. In planning activities, the aim has been to adapt the work to changing conditions and needs of the mining industries and to avoid becoming bound to any particular type of investigation when others are found to be of more pressing interest.

Jan 1, 1939

By Wils L. Cooley

The report covers several aspects of mine safety ground systems, primarily for underground coal mines. The design of a combined ground fault-ground check monitoring system is presented. An analysis is made of grounding systems for dc shuttle cars. Complete resistance data and results of physical inspections of self-salting ground rods are presented. A detailed resistance and economic analysis is presented for the use of composite materials for building inexpensive and effective ground beds in high-resistivity areas. The desireability of penetrating the coal seam with a borehole safety ground is investigated. A report is made of a Mine Substation Grounding and Bonding Workshop.

Jan 1, 1980

By R. L. Schmidt

One of a series published by the Bureau of Mines covering research investigations in rock drillability, this report of field drilling results extends earlier laboratory findings and provides a relatively simple procedure for predicting percussive drilling rates with reasonable accuracy. Two percussive drills mounted on a truck were used to drill a total of 25 rock types, and the results were used to develop a prediction equation. The equation was tested on a set of unrelated laboratory percussive drilling data, and the comparison between predicted and actual rates is shown in tabular form.

Jan 1, 1972

By J. W. Paul

The United States Bureau of Mines has made a study of roof control in 68 mines operating in the Pittsburgh coal bed in Pennsylvania, West Virginia, and Ohio. In making these studies, much information was also obtained on various exact methods of development and pillar extraction as practiced by this large group of mines. It is proposed in this paper to describe these methods, by which this group of mines in 1931, a year of reduced industrial activity, produced 28,123,000 tons of bituminous coal - 7.4 percent of the national production for the same year and an amount equal to the combined production of the coal mired in the States of Alabama, Colorado, New Mexico, Utah, and Wyoming. The results of these studies, insofar as they pertain to the prevention of injuries from falls of roof, have been published by the Bureau of Mines. In this paper only a few mines typical of each system will be described; however, should the reader be interested in other details with respect to these mines, he may refer to the following publications: T.P. 522, 1932, 43 pp. Falls of roof and coal in mines operating in the Pittsburgh coal bed in Marion and Monongalia Counties, W. Va., by J. W. Paul and J. N. Geyer.- A study of nine mines in these two counties of northern West Virginia.

Jan 1, 1935

By R. W. Stahl

The use of continuous mining machines has greatly minimized the necessity for blasting in coal mines, even during pillar recovery; however, explosives are still used to blast stumps. The use of improper blasting materials, improper procedures, or both has caused mine explosions and fires, with loss of life and property damage. Researchers and manufacturers are continuously improving explosives and blasting accessories; use of the more recently developed materials will make the blasting operation safer. Extreme caution is mandatory when blasting stumps, as the ignition of methane or coal dust may trigger an explosion or cause a fire. Since the blasting of stumps will no doubt continue, although often unnecessarily, this paper summarizes recent findings published by the Bureau of Mines and recommends safer methods.

Jan 1, 1962

By S. Vennos

As a result of Synopsis 73-16 Dynadyne responded with an unsolicited proposal offering the Bureau of Mines to develop an ultra-low volume coal mine dust personal sampler. In the ensuing technical discussions the choice of a desirable volumetric rate became a focal point. While, the initial proposal was based on a volumetric rate in the area of 50 cc/min the Government expressed interest in a variety of mass flow rates ranging from 50 cc/min to 2000 cc/min. The physical characteristics such as weight, volume and configuration of a personal sampler are to a large extent - dependent on the operating volumetric rate. It became readily apparent that the optimum size of such an instrument as a function of volumetric rate was not known and that a study of the choice of optima was essential prior to beginning the development, Hence, the Government authorized a two phase approach to this project. Phase I was to include a Technical Evaluation Study of optimum characteristics in the range between 0. 1 to 2. 0 lpm. Based on these findings and in consultation with MESA personnel, the Bureau of Mines was to authorize the second phase that is, the development. Phase II, was to include the drawing of a set of performance specifications stating among others the desired operating volumetric rate. In this report, every effort was made not only to present the actual work done over the course of this development, but to reflect also our engineering "thinking" providing answers as to the "why" we preferred certain solutions over others. We believe that this added dimension is not only useful for the Government official evaluating this report, but also that the Government is entitled to it providing the official with an educational content useful in avoiding future costly repetitions of similar situations.

Jan 1, 1975

By B. J. Moore

This Bureau of Mines publication estimates that U.S. helium resources as of January 1977 were 710 billion cubic feet. These resources are broken down into four classifications, as follows: Helium in measured natural gas resources and in storage, 201 billion cubic feet; helium in indicated natural gas resources, 150 billion cubic feet; helium in hypothetical natural gas resources, 175 billion cubic feet; and helium in speculative natural gas resources, 184 billion cubic feet.2 Most of the helium in natural gas is presently dissipated as natural gas is consumed as fuel and for other purposes. Helium resources of the United States may also be divided into three other categories: (1) Depleting and undiscovered natural gas resources, 589 billion cubic feet; (2) nondepleting natural gas, 83 billion cubic feet; and (3) storage, 38 billion cubic feet, of which 37 billion cubic feet is federally owned and 1 billion cubic feet is privately owned. The United States does not have any significant leasehold rights in the depleting fuel gas resources. However, through the Department of the Interior, it does have leasehold rights to about 70 percent of the helium found in nondepleting natural gas, and it owns over 90 percent of the helium in storage.

Jan 1, 1979

By H. B. Humphrey

[EXPLOSION of gas and dust in coal mines, have caused death t lid injure to mines, and destruction of workings in all countries where coal is mined underground. In the United Stales the first reported explosion wits in Min; explosions have continued to the present. The danger to film ill it mine When an explosion occurs in not always measured by the violence created or by their nevi lies, to the area through which flame and Violence extend. As many, perhaps more, risen have died from gases and lade of oxygen (known as "after-damp") than have been killed by the blast and hart. Me explosions often are caused by it combination of factors, including concentration of methane in air, formation of clouds of dust, and the presence of a flame or spark. These explosion factors have varied with changes ill milting method and practises over the years, but the basis causes have always been the salve. Understanding of the causes and to acceptance of ways to guard against explosions and their effects have been slow to spread from investigates to officials and Own to bosses and miners. To a considerable extent there hats lawn a belief that explosions were a joining risk but might hr, put oil hut could not be presented. Such belief is based on the human failure to maintain and observe necessary precautions. These failures, caused by inertia to change, carelessness, or reliance on continuance, of past explosion-free years, are being reduced in number and effect by education of miners and supervisors and acceptance of higher prevention standards.]

Jan 1, 1959

By J. M. Goris

The U.S. Bureau of Mines is conducting research on cable bolt ground supports to assess their material and support properties, to provide design criteria for using cable bolt supports as roof control systems under various types of underground mining conditions, and to provide a mathematical model of cable bolt support systems. Part 1 describes laboratory studies of the support properties of cable bolts made of conventional steel cables and provides recommendations on such topics as the use of thick grouts, selection of breather tubes, and reduction of water bleeding in cement-based grouts. The studies evaluated both single and double cables; effects of different embedment lengths, water-cement ratios, and grout curing temperatures on support strength; effects of use or nonuse of breather tubes; pumpability and water-bleeding properties of grouts; and the strength properties of sand-cement grouts. Part 2 will cover the strength characteristics of birdcage cable bolt supports, epoxy-coated cables, and cables with steel buttons attached.

Jan 1, 1990

By V. B. Dale

This is one of a series of reports covering the mineral resources of the Nation. It describes briefly most of the known tungsten deposits in Yuma, Maricopa, Pinal, and Graham Counties, Ariz. Most of those described were examined by the author. An effort was made to determine the position of the various deposits by section, township, and range and to give accurate road direction to each property from a prominent landmark. All available maps have been used in making these determinations, but in unsurveyed areas it was necessary to make approximate projections of subdivisions. The township and range numbers refer to the Gila and Salt River base and meridian.

Jan 1, 1959

By Roy L. Grant

The Bureau of Mines investigated the up-and-down method with factorial designs to determine if shorter, and therefore less costly, trial sequences could be used. Although sequences of 50 trials are usually recommended, sequences of 20 trials were arbitrarily chosen for the experiments with permissible coal mine explosives described in this report. These explosives were fired from a cannon pointed into a flammable natural gas-air atmosphere at the Bureau of Mines Explosives Research Center gallery to ascertain their safety properties. The investigation demonstrated that the shorter sequences led to useful conclusions with a reduction in cost of the experimental program.

Jan 1, 1967

This NIOSH Toolbox Training program contains 52 different modules designed to stimulate safety discussions among your employees. Each module is intended to be completed in roughly 10 or 15 minutes, so a Toolbox Training session can be conducted once a week for the entire year. Each session counts toward your employee’s 8-hour annual MSHA refresher training, thus saving an entire day of work.. The modules are used to refresh employees on the procedures, policies, and practices of working safely at a specific mine site and can easily be tailored to fit conditions and situations found on your property. Every module follows the same format, so that as the weeks pass, miners will start to approach every safety situation in the same way. A typical Toolbox Training session contains five basic steps that cover all the information in the module. 1. Identification of the hazard and discussions about the types of injuries typically associated with the hazard. 2. Discussions of some of the causes of the hazard. The MSHA example included with each module should be referenced. 3. After the hazard and accident has been explained and understood, discussions about best practices and tips for avoiding a similar accident. 4. Review of similar conditions or near misses from your mine site using the leading questions on the form to start a discussion. Specific examples of equipment or structures on the site that could lead to the same accident should be discussed. The blank space on the module is used to add your own remarks and questions to supplement the given information. 5. Miners fill out the training record on the back of the form with name, initials, and date of training session. The modules are designed to be kept in a standard three-ring binder and easily photocopied. This way, the same set of modules can be used for years to come. A blank form is included that can be used to create more Toolbox Training modules. The key component of Toolbox Training is to start a discussion among employees that will allow them to see the hazards around them every day and respond to these hazards in a safe and consistent manner. To start a discussion, ask questions that need more than a one-word response. Get the miners to talk about similar situations from their own experiences and give suggestions about how to fix the hazards around them. Toolbox Training is a quick and effective way to cover specific mining hazards, but it only works if miners are involved in the discussion.

Jan 1, 2004

The annual reports of the supervising engineers of the seven sections comprising the Mining Division are assembled in the following pages and constitute the annual report of the division. In planning activities, the aim has been to adapt the work to changing conditions and needs of the mining industries and to avoid becoming bound to any particular type of investigation when others are found to be of more pressing interest.

Jan 1, 1939

By H. R. Appell

The Bureau of Mines is experimentally converting cellulose, the chief constituent of organic solid waste, to a low-sulfur oil, All types of cellulosic wastes, including urban refuse, agricultural wastes, sewage sludge, wood, lignin, and bovine manure, have been converted to oil by reaction with carbon monoxide and water at temperatures of 350° to 400° C and pressures near 4,000 psig, and in the presence of various catalysts and solvents, Cellulose conversions of 90 percent and better (corresponding to oil yields of 40 to 50 percent) have been obtained. A continuous reactor for use at maximum conditions up to 500° C and 5,000 psig has been operated successfully, Using sucrose as a feedstock, operation in this system has permitted a simplified and preliminary chemical study of the conversion process. Oil yields of over 30 percent have been obtained with this unit.

Jan 1, 1971

By E. P. Youngman

The mining law of British North Borneo is entitled " The Mining Ordinance , 1927. 113 The only mining regulation or rule available is " Rules 313 , 114 passed in accordance with article 26 of the ordinance of 1927. Before the passage of this legislation , the country had no specific law governing the granting of mineral rights , although the land law contained provisions relating to mining lands . The land ordinance of 19135 still controls in a few details . All references in this paper , unless otherwise specifically designated , are to the mining ordinance .

Mar 1, 1933

By C. H. Fisher

[Many methods of analyzing tar oils for their tar acid and base content have bun employed in connection with both academic and. industrial investigations. Most of these analytical procedures are based on the diminution in volume caused by extraction with alkali and mineral acids (contraction method), although other methods haves been employed.4/ In many instances the adoption of an analytical method was not preceded by adequate study, and, as a consequence, the literature, on this subject is conspicuous for its contradictory claims and recommendations. It has bin shown in the, case of certain synthetic solutions5/ that large errors may result if the analysis is carried out by simple extraction with alkali and mineral acids.]

Jan 1, 1936

By Sidney Katell

This study estimates capital investment, operating costs, and selling prices for four underground bituminous mines producing coal with annual production ranging from 1.06 to 4.99 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of December 6, 1974, under the Bituminous Wage Agreement of 1974, and costs for material and equipment are based on 1975 indexes. Initial capital investment ranges from $20,799,800 for the 1 .06- million-ton-per-year (MM tpy) mine to $84,027,500 for the 4.99-MM-tpy mine. Total capital investment ranges from $32,506,800 to $1 22,983,500 for the same mines. Corresponding selling prices for the coal range from $12.87 to $11.64 per ton, assuming a 15-percent discounted cash flow rate of return after Federal income taxes.

Jan 1, 1976

By M. D. Balen

The U. S. Bureau of Mines has undertaken the development of mineral industry cost escalation factors to enable the estimation of mineral development and extraction costs for mineralized sites in Alaska throught the use of the Bureau's Cost Estimating System v2.0 (CES 2.0). For the purposes of this document, all calculations are based on, and reflect the economic environment in Alaska in July 1992. The greater cost of mining in Alaska as compared to the contiguous-48 States can be estimated for Alaskan mining operations through (1 ) the analysis of capital and operating costs for analogous mine and mill plants in operation in the contiguous-48 States; (2) the hypothetical relocation of mine and mill plants from their actual location(s) to Alaska by making engineering modifications to the mine and mill plant design as required by the Alaskan site characteristics; (3) calculation of the cost of the required engineering modifications and; (4) the escalation of all costs to a level representative of the economic environment in Alaska at some specific point in time.

Jan 1, 2011

By R. J. Fantel

The Bureau of Mines investigated the resources, costs, capacities, market relationships, and short- and long-run supply of phosphate rock and phosphoric acid. The 206 mines and deposits evaluated in 30 market economy countries contain an estimated 35.1 billion mt of recoverable phosphate rock (demonstrated resource level). U.S. resources are sufficient to satisfy the domestic and export markets for phosphate products well beyond the year 2000. Because of resource depletion at current producers, however, new properties (with higher cost levels) need to be developed if U.S. production levels are to be maintained. Existing worldwide capacity can satisfy expected demand through the early 1990's. Expansion at existing mines or low demand growth could mean that no new property development will be needed before the late 1990's. Worldwide, almost $8 billion could be required for development of new phosphate rock properties between now and the year 2000, given 3-pct annual growth in demand. Most properties that could develop in the 1990's would require price increases of 20 to 50 pct to break even. To earn a 15-pct rate of return on investment, prices must rise to nearly double the present level of $24 to $29 per metric ton.

Jan 1, 1988

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