Search Documents

By D. T. Bergado

The uppermost subsoil profiles of the Bangkok plain can be divided into four layers, namely: weathered clay, soft clay, stiff clay, and dense sand layers. The soft Bangkok clay is a normally consolidated marine clay with built-up preconsolidation effects and overlain by a weathered crust. Up to the present, a large number of full-scale tests on excavations and pile foundations has been made by numerous investigators. Based on these results, the available data are reviewed and evaluated. The results show that for test excavations, the excess pore pressures were overpredicted by the existing theories. The vertical and lateral movements in the excavations can be predicted by the bilinear and non-linear finite elements using appropriate modulus values. Relationships among probability of failure, safety factor, and safety margin of the excavation were also obtained. In the case of pile foundations, good agreement between the measured and predicted ultimate pile capacities were obtained for long piles. The adhesion factors ranged from 0.4 to 1.0 while the average skin friction factor was found to be 0.33. The ultimate capacity of the pile was also predicted successfully by using the Dutch cone data. For lateral deflection of piles, Davisson and Gill's theory predicted well in the low deflection zone while Poulos' theory agreed well in the high deflection zone. From the probabilistic analysis of ultimate pile capacity, the probability of failure was related to the central factor of safety. The piles usually used in Bangkok area are mainly precast concrete piles

Jan 1, 2010

By Katherine A. Klein

Refuge chambers may potentially save the lives of miners during a mine emergency. For this reason, it is crucial that miners know how to operate them. Unfortunately, because refuge chambers provide so many services, they can be very complicated and difficult to operate. Therefore, NIOSH has created this document with suggestions for developing manuals and educational materials. A multidisciplinary team comprised of NIOSH engineers, sociologists, psychologists, health communication professionals, and geologists developed the recommendations contained in this document. These recommendations are based on an evaluation of manufacturers? instruction manuals from both the U.S. and globally, interviews with over 20 mining and safety experts, and an extensive literature review. This research, focused on the best practices for refuge chambers, led to the formulation of this document. It is intended to offer suggestions to manufacturers and mine operators on how to create effective and easy-to-understand training manuals for miners as well as tips to create the most comfortable and usable refuge chambers. It should be noted that these recommendations are not meant to substitute for manufacturer-supplied materials but rather to be used in conjunction with manufacturer?s materials. Manufacturers should always be consulted for up-to-date information about their chamber. Although different states and different mines refer to underground refuges by different names, this guide will simply refer to underground refuges nearest to the face as refuge chambers, whether inflatable from a skid or constructed from steel. Other popular terms for refuge chambers are rescue chambers, rescue shelters, and refuge shelters. Refuges that are nearer to the shaft, whether a prefabricated refuge chamber or one built into a crosscut, will be referred to as outby refuges because of their location in the mine. Outby refuges can be permanent, semipermanent, or portable and are usually located at every other SCSR cache. Outby refuges are sometimes called hardened rooms, outby shelters, and in-place shelters. When discussing outby refuges and refuge chambers collectively, this guide will refer to them as underground refuges. Other terms for underground refuges include refuge alternatives, locations of safety, and safe havens. This document is designed to be read either cover to cover or by specific section. It is recommended that on first read, this guide be read cover to cover. In subsequent readings, manufacturers and mine operators may find it easier to use the table of contents page to locate specific information on parts of the refuge chamber.

Jan 1, 2009

By Oliver C. Ralston

[This paper is an expanded revision of a report entitled "Froth Flotation and Agglomerate Tabling of Nonmetallic Minerals, " published in Transactions of the Canadian Institute of Mining and Metallurgy (vol. 40, November 1937, pp- 691-726) and prepared a year previously. Revisions embodied herein brine the data up to January 1, 1938. References have also been added to make the earlier paper more complete for the period it covered.]

Jan 1, 1938

By Oliver C. Ralston

[This paper is an expmded revision of a report entitled "Froth Flota- tion and Agglomerate Tabling of Honmetdlic Idinerds, " published in Trans- actions of the Canadian Ir-stitute of Iriining and !,letdlurgy (vol. 40, November 1937, pp- 6? 1-726) and al'enared a year pr~viousl:~. Revisions en'oodied herein brinc the &ta I:T to Jn?uac"g 1, 193;. References have also been added to make the earlier paper more complete for the period it covered. This paper is an expmded revision of a report entitled "Froth Flota- tion and Agglomerate Tabling of Honmetdlic Idinerds, " published in Trans- actions of the Canadian Ir-stitute of Iriining and !,letdlurgy (vol. 40, November 1937, pp- 6? 1-726) and al'enared a year pr~viousl:~. Revisions en'oodied herein brinc the &ta I:T to Jn?uac"g 1, 193;. References have also been added to make the earlier paper more complete for the period it covered.]

Jan 1, 1938

By Joseph Jensen

MANY fields have been zoned by nature with shales and intermediate waters between oil zones. Limitations thus imposed have been the basis on which the field was developed. In contrast thereto, in the Ventura Avenue Field, nature proved more generous. Always expecting to find such similar limitations, operators drilled deeper and deeper into the oil zone without finding any distinctive shale bodies other that the Gosnell shale and only one intermediate water, which became the point below which the final water shut-off of each well was made. Thus, on top of the structure, about 3300 ft. of oil-bearing zone has been penetrated below this intermediate w9ter-a distance of 4000 ft. below the Gosnell shale. At first it seemed that the greater the penetration in the zone, the better the well. The error of this assumption became evident

Jan 1, 1930

By T. F. Anstett

The Bureau of Mines evaluated the potential availability of chrysotile, amosite, and crocidolite asbestos from 42 properties in market economy countries. This resulted in the development of tonnage-cost relationships indicating the quantity of grades 3 through 7 asbestos at various average total costs of production at 0% and 15% rates of return on invested capital. The availability of grades 2 and 8 was also evaluated, but since each is produced at only one property, no analytical results were given. Total demonstrated recoverable chrysotile fiber potentially available of grades 3 through 7 from the 42 properties evaluated follow: 1.59 million t, 21.00 million t, 16.74 million t, 15.54 million t, and 19.27 million t, respectively. The total amount of crocidolite is 1.69 million t. Owing to the good potential for discovery and development of new deposits, long- term availability of fiber of all three types is not in jeopardy. However, many of the crocidolite properties evaluated in the northern Cape crocidolite field of South Africa have relatively small demonstrated resources, and new deposits will have to be exploited by the late 1990's to sustain projected levels of production.

Jan 1, 1985

By Jennifer L. Bell, PATRICK L. YORIO, Emily J. Haas, Susan M. Moore, Lee A. Greenawald

Although researchers have struggled to replicate Heinrich’s safety triangle findings (Heinrich 1931) for various reasons (e.g., no access to his original database and it is unclear if the database was of a single establishment/operation or for an entire industry), the occupational safety community has continued to adopt and expand the applications of this theory (e.g., McSween 2003). Within the mining industry, the potential exists for operations and companies to use concepts from the safety triangle as a way to inform or challenge the practices employed within their health and safety management systems (HSMS) to prevent incidents (Backlund 2016). This paper considers data obtained from the Mine Safety and Health Administration’s databases and demonstrates the validity of applying the safety triangle theory at the mine level. The results support the use of this theory and demonstrate that lower severity incidents can predict fatalities in a subsequent year where significant nuances and caveats to applying the theory are identified and discussed.

Jul 25, 2020

By Paul Billingsley

THE development of the North Lily ground, which lies in the East Tintic district, Utah,. about half a mile northwest of the famous Tintic Standard mine, was undertaken by the International Smelting Co. on purely geological reasoning. The geologic theory on which this work was based resulted from several years' intensive study of the East Tintic district by the geological department of the International Smelt-ing Co., who were, during this period, indebted to many for valuable suggestions that were adopted and became part, of the gradually maturing concept. For example, E. J. Raddatz, president of the Tintic Standard Mining Co., first called attention to the significance of rhyolite alteration; J. W. Wade, assistant manager, contributed greatly to our knowledge of the great Tintic Standard orebodies; and so on all along. the line. In short, the ultimate theory embodies the aggregate experience and thought of all those most familiar with the area in question. The problem in brief was this: is the Tintic Standard deposit an isolated occurrence of ore, or are other ore deposits to be found in the vicinity? If the latter is the case, where can these others be looked for? The difficulty of the problem lay in the fact that most of the area is covered by rhyolite; beneath which lies the limestone in which the orebodies occur; so that the available evidence as to the structure of the formations, and, their mineralization; is of the slightest. The sav-ing features of the case, by means of which it proved possible to solve the problem, are three in number first, the rhyolite is pre-mineral and hence has been exposed to alteration by the mineralizing agencies; second, certain persistent dikes and fissures are con-tinuous through the rhyolite into the limestone below; and third, the extensive underground workings of the Tintic Standard gave a good basis for study of the sub-rhyolite structure and the occurrence of ore. The rhyolite overlies the Tintic Standard orebodies, and over them shows a large patch of brownish altera-tion. This patch proves to be due to chloritization and sericitization, which has spread out from certain zones of dikes, pebble-dikes and fissures. The dikes are com-posed of a light fine-grained rock which has been altered to an aggregate of quartz, alunite, and magnetite. They can be traced southwest to a common center in Big Hill, the entire mass of which is composed of the same material. The pebble-dikes, which consist of a mass of rounded pebbles, mainly quartzite, in a matrix ranging from the same quartz-alunite-magnetite rock as above to almost pure vein quartz, are closely asso-ciated with these light dikes, but in general extend farther northeast. They thus represent a specialized phase of the intrusive action of which Big Hill is the center. The brown chloritized rhyolite, then, is an alteration product due, in all. probability, to emana-tions closely associated with this phase. Since it coin-cides geographically with the Tintic Standard area of highly altered limestone, with its many great ore-bodies, it has been concluded, that it is the expression in the rhyolite of activities which have also altered and mineralized' the underlying limestone.

Jan 4, 1927

By G. E. Johnson

Batch tests of coals and coal-derived materials were made by the Bureau of Mines to determine their effectiveness in removing organic contaminants (COD or chemical oxygen demand, comprising those organic compounds that can be chemically oxidized, and ABS or alkylbenzene sulfonate, common household detergents) from the final effluent of secondary-treated waste waters. The adsorptive capacities of flyashes, coals, including at least one sample of each rank found in this country, pretreated coals, and miscellaneous materials including commercial chars and coke, were determined and compared with that of granular activated carbon. The coals, though not as effective as activated carbon, possess an economic advantage--they are relatively inexpensive, and they can still be burned as fuel without any loss of fuel value after use in waste¬water treatment. A hvcb coal was found to be one of the best, having about one-fourth the capacity of activated carbon for COD, adsorbing about 4 percent of its weight before it became saturated. Several coals contained constituents that added to the COD content of the treated water. Thus knowledge of the performance of the coal is necessary to insure selection of a proper coal as adsorbent.

Jan 1, 1966

By William Crowe Kellogg

By now the term AFMAG has been fairly well introduced to the mining industry. Several papers have been presented and published concerning AFMAG (references 1 and 2). However, the term AFMAG remains rather new to the industry, and the exact place which AFMAG occupies in the minerals exploration field is still somewhat uncertain in the minds of many who may have use for this new and interesting method of electromagnetic exploration for conductive minerals. It is the purpose of this paper to again review the basic theory of the AFMAG system, to describe and - illustrate the equipment and data presentation as used in aerial surveying, and to provide some idea of the cost and nature of airborne AFMAG surveys. This paper is primarily of a general descriptive nature and presents AFMAG theory in a schematic rather than mathematical form; emphasis is placed on the equipment, the present method of data presentation and survey operations, since it is believed that such, information will now generally best serve to inform the mining industry of the characteristics of the AFMAG system.

Jan 1, 1960

By Lorraine B. Burgin

This study by the Bureau of Mines documents the leadtime required for preliminary and detailed exploration, development of the mine, and construction of beneficiation and support facilities for selected copper deposits in Arizona. The time for major exploration ranged from 1 to 15 years, time for open pit development (or construction) was 1 to 4 years, and time for under- ground development was 4 to 8 years; one underground mine presently being developed may require 12 years to achieve production. Construction of the beneficiation plants required 8 months to just over 2 years. The data are supported by historical facts for each deposit during the leadtime stages from location of claims through exploration, construction, expansion, and leaching. The sequence of development and factors contributing to differences in the time spans are discussed. Histories are detailed for the Miami, Castle Dome, Copper Cities, San Manuel-Kalamazoo, and Twin Buttes properties; briefly summarized are the Pinto Valley, Miami East, Esperanza-Sierrita, Pima, and Mineral Park Properties. Each mining operation had its own pattern of development, and together they present a source of planning information for the development of other properties.

Jan 1, 1976

By Art Carino

"The McClean Lake operation is located in the Eastern Shore of the Athabasca Basin in northern Saskatchewan some 700-air kilometers north of Saskatoon. It is operated by Cogema Resources Inc., the major share holder of the joint venture consisting of Cogema Resources Inc., Denison Mines Limited and OURD, a consortium of Japanese utilities.The JEB mill is the first uranium mill to be constructed and licensed in North America within the last 15 years. The mill uses conventional uranium unit process but employs innovative techniques unique to the JEB mill.This paper presents brief descriptions of the various unit processes, the innovations and the commissioning strategies developed to achieve the designed production capacity in the shortest possible time.INTRODUCTIONThe McClean Lake ore body was discovered in 1979, followed by the discovery of the JEB ore body in 1982. From 1985 to 1990, a cluster of deposits named Sue A, Sue B and Sue C were discovered. Environmental Impact Assessment (EIS) of the McClean Lake project began in 1990 under a joint federal-provincial process. Following the public hearings in 1993, the governments gave approval to proceed with the construction of the project, subject to fulfilling licensing requirements.The McClean Lake ores are located in the uranium-rich geological region of Saskatchewan known as the Athabasca Basin, 700 air kilometers north of Saskatoon. The JEB mill is located near the mined out JEB open pit that is now used as the tailing depository.The approved mill has a production capacity of 6,000,000 pounds of U3O8 annually and is capable and licensed to process JEB, Sue A, Sue B, Sue C, McClean Lake, and Midwest Lake deposits. Although the EIS has been approved, Mining of the Midwest Lake deposit has not been approved at this time."

Jan 1, 2001

By Raymond P. Miller

This two volume report addresses slope stability of surface mine spoils within the Interior Coal Province. Sixteen (16) mines were visited, pertinent data and samples collected, and reported spoil instabilities back-analyzed. Laboratory test results are compared to back-analyzed material properties. Available methods of slope stability analysis are reviewed and evaluated with respect to application to mine spoil stability evaluation and prediction. Correlation and tentative relationships among spoil material properties, highwall conditions, mining equipment and procedures and empirical observations are presented. Slope stability sensitivity plots illustrate the relative significance of various input parameters on stability. Slope stability input parameters are correlated with site and mining conditions to identify the primary factors controlling spoil stability. Investigative methods, spoil stability enhancement techniques, spoil stability prediction procedures and future study areas are discussed. Appendices include a glossary of terms, annotated bibliography, details of mine visits, and detailed laboratory test procedures and results.

Jan 1, 1979

By J. Reed

The RockWorks EarthApps represent a free collection of 74 geology-related programs that read data from a built-in datasheet and create diagrams within Google Earth. EarthApps also includes programs that extract data from Google Earth. The programs that create diagrams include: point mapping (e.g. borehole locations), proportionally scaled icons (e.g. geochemistry), and strike & dip symbols. Line mapping utilities include; polylines, parabolas and pipelines. Polygon mapping programs include; thematic mapping (e.g. geology), mining claims, and public land survey sections. Image overlay capabilities include; draping (e.g. geologic maps) and time-based animations. Vertical image display capabilities are centered on either midpoints (e.g. drill-hole logs) or stretched between endpoints (e.g. cross-sections). The Flyover programs create virtual tours for site presentations. The cell-mapping includes a variety of algorithms (e.g. geochemical and geophysical contouring). Survey programs convert and export survey data to Google Earth as points and polygons. Programs that extract data from Google Earth include; points, lineations, polylines, and polygons. The RockWorks/EarthApps collection is developed by RockWare Incorporated based in Golden, Colorado.

Feb 27, 2013

By P. R. Jones

A computer program was written for the design of a shell and tube heat exchanger on a price optimum basis for the following conditions: (1) Triangular pitch; (2) single or multiple pass; (3) heating or cooling; (4) no change in phase; and (5) inside pumping costs immaterial. Price optimum design was obtained for four standard tube sizes and standard pitch. The inside pressure drop was fixed and outside pressure drop was computed for the optimum baffle spacing and when the baffle spacing equaled the shell diameter. Standard shells whose areas equaled or exceeded the required area were also listed. The program was made adaptable to various fluids and to various tube sizes and pitch by reading in many of the required data such as physical properties of the fluids, tube data, and standard shell data in tabular form.

Jan 1, 1968

By D Yan, D Connelly

Beneficiation of magnetite is an integral part of the future of iron ore processing. Historically, the focus of Western Australian producers has been on exporting direct shipping ore (DSO) namely haematite. The future for new DSO resources is limited so companies are changing their emphasis into processing the very large, undeveloped magnetite ores in Western Australia (WA), using beneficiation to produce shippable magnetite concentrates. These magnetite resources require higher cost processing techniques such as fine grinding and beneficiation to produce saleable concentrates. This distinct difference, from the DSO ores, has led to the development of a number of new technologies. This paper reviews: the different techniques used for magnetite beneficiation and provides some case studies in the WA industry; the use of mineral liberation analysis (MLA) to describe the nature, grain size, occurrence and associations of the mineralisation;the consideration of coarse cobbing as a critical upgrading; the application of high pressure grinding rolls (HPGR) to save energy; how the field of magnetic separation has resulted in new machines with higher field strength (SLon Separators); ultra fine grinding requirements of magnetite concentrates; andthe application of reverse flotation to reduce silica in the concentrates.

Jan 1, 2009

By W. A. Calhoun

This investigation of low-grade bauxites as potential sources of aluminum by caustic desilication and alumina extraction was undertaken by the Bureau of Mines to develop extractive methods for winning alumina from domestic deposits of low-grade bauxites. This report is the second of a series covering the work by the Bureau of Mines' Rolla, Mo., and Bauxite, Ark., laboratories. The first report published in the Journal of Metals, December 1951,3/ and dealt with kaolin and halloysite. The present investigation is concerned with low-grade bauxites only. The purpose of these investigations is to increase the domestic supply of aluminum ores. With eventual depletion of high-grade deposits, aluminous materials, such as low-grade bauxite, clays, shales, and high-iron laterites, will become our principal domestic sources of aluminum. The development of extractive processes for winning alumina from these low-grade materials is one of the many national security measures undertaken by the Bureau of Mines. A method has-been developed in the laboratory for successfully treating high-silica bauxites from domestic deposits. In this process the bauxite was calcined at 980° C. to form amorphous silica and alumina. The calcine was then leached by percolation with 15-percent sodium hydroxide solution at 940 to 96° C., removing 67 to 77 percent of the silica with a loss of 4.1 to 5.0 percent of the alumina. The sodium hydroxide in the spent liquor used in desilication was 95 percent recoverable, and comparable desilication results were obtained with 100-percent reclaimed liquor, The indicated cost of reagents, for sodium hydroxide and lime used in the desilication and regenera¬tion of spent liquor, was about $4.00 per ton of calcine treated.

Jan 1, 1954

By E. D. Gardner

From the standpoint of tonnage and dollar value copper is the most important nonferrous metal mined in North America. The opening of copper mines has had an important bearing on the development and settlement of many sections of the continent. The prosperity of many of the mining States or provinces depends directly upon the copper-mining industry. Normally, about 35,000 men are employed in the copper mines, mills, and smelters of the United States. The United States is the most important producer of copper among the nations; more copper is mined in North America than in any other continent, and for many years the United States alone produced about half of the copper of the world. During the last 10 years increasing production in South America and Africa has reduced the relative importance of North America and the United States.

Jan 1, 1938

By J. W. Thompson

ORES PROCESS OF ORE CONCENTRATION-PATENTABILITY. The patent issued to Sulman, Pickard, and Ballot, November 6, 1905, and assigned to Minerals Separation and Minerals Separation American Syndicate, for new and useful improvements in ore concen- tration, its object being to separate metalliferous matter from gangue by means of oils and fatty acids that have a preferential affinity for such metalliferous matter, the principal feature of which is "agitat- ing the mixture to cause the oil-coated mineral to form a froth," was clearly anticipated by other patents, and each step in the process described in the Sulman, Pickard, and Ballot patent is fully described in more than one of the prior patents, with the single exception of the reduced quantity of oil used; but the discovery that the small fraction of oil is sufficient to produce flotation of the metalliferous matter can not be made by itself or in combination, the subject of a patent. Hyde v. Minerals Separation, 214 Fed., 100, p. 109, May, 1914. ACTION FOR CONVERSION OF MINERALS. In an action by the grantor of a certain mine and mining property against his grantee to recover damages for the conversion of a quantity of ore that the grantor before the conveyance had mined and extracted from the mine and placed on the dump near the mine, the plaintiff is not entitled to recover where it appears that at the time the ore was placed on the dump the mine was owned and operated by a mining company and that at the time the ore was taken out of the mine the company had no intention of doing anything with it but simply deposited it on the dump as waste and to give an opportunity to develop the mine and get better ore to send to the smelter, and that

Jan 1, 1915

By R. S. Dean

As set forth in the decision of the Trail Smelter Arbitral Tribunal, dated April 16, 1938 This Tribunal is constituted under and its powers are derived from and limited by the convention between the United States of America and the Dominion of Canada signed at Ottawa, April 15, 1935, duly ratified by the two parties and ratification exchanged at Ottawa, August 3, 1935 (hereinafter termed "the Convention") . . . The duty imposed upon the Tribunal by the Convention was to "finally decide" the following questions: (1) Whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January 1932, and, if so, what indemnity should be paid therefor? (2) In the event of the answer to the first part of the preceding Question being in the affirmative, whether the Trail Smelter should be required to refrain from causing damage in the State of Washington in the future and, if so, to what extent? (3) In the light of the answer to the preceding Question, what measures or regime, if any, should be adopted or maintained by the Trail Smelter? (4) What indemnity or compensation, if any, should be paid on account of any decision or decisions rendered by the Tribunal pursuant to the next two preceding Questions? In this decision reported to the Government of the United States of America and to the Government of the Dominion of Canada, the Tribunal answered the first question in its entirety and reserved decision on the other three questions in accordance with the following extract from their decision

Jan 1, 1944