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By Earl Oliver

Some two years ago the Petroleum Division of the A. I. M. E. organized a special study of unit operation. That method of handling oil pools had been urged as the remedy that would save the United States petroleum industry from the crisis that even then loomed as more than a small cloud on the horizon. Today it is only one of several remedies vigorously advocated. Proration, regulation of imports, unit operation, constructive marketing and interstate compacts all have their earnest proponents, but the advocates of each have been disposed to look with indifference on the other respective proposals, with the result that none has had united support. Meanwhile the industry has drifted rapidly toward a serious crisis, the imminence of which in itself may bring the solution. The gravity of the situation tends to force study of the merits of proposals that a short time previously were brushed aside as impractical; and to the surprise of most of us we now find merit where previously we thought none existed. Irrespective of what might have been the result had any single proposal being adopted years ago, it is now apparent that under present conditions no one of the remedies—unit operation, proration, regulation of imports or constructive marketing—standing alone would be of much benefit. On the other hand, it is becoming evident that a well balanced program comprising all four of these remedies might save the United States petroleum industry; also that some such comprehensive program might be necessary to save it. It is even becoming evident that the despised interstate compact might be an appropriate type of machinery in which to group and coordinate all these remedies. We have progressed beyond the belief that either the industry or the government working alone can correct the situation, and have arrived at the more healthy realization that the task will require most sympathetic cooperation between government and industry, backed by an equally sympathetic public understanding. If we were functioning under a Mussolini or a Stalin, stabilizing the petroleum industry would be a much simpler task. However, in the

Jan 1, 1931

By James Scott

Outline Deposit Overview and Brief History ?Geologic Setting ?Local Geology ?Petrography ?Geochemistry ?Mineralization ?Geochronology ?Conclusions Deposit Overview ?Porphyry Cu-Mo-Au ?Discovered 1957 (BIK Syndicate) ?Various programs, most significant: ?Hecla(1970s) ?Teck(Late 1970s Early 1980s) ?Copper Fox Metals (2005 -Ongoing ?optioned from TeckComincoin 2002) ?Measured and Indicated Resources: ?847Mt grading: ?0.292% Cu ?0.019% Mo ?0.202g/t Au ?1.796g/t Ag ?Total ~ 0.485 % Cu Eq.

May 1, 2006

By Harry Dobroski, Larry G. Stolarczyk

Theoretical and experimental research sponsored by the U.S. Bureau of Mines shows that medium frequency (MF) electromagnetic (EM) signals propagate great distances in an underground environment such as a tunnel or mine. This propagation is enhanced by different mechanisms associated with the geology, and with the existence of metallic conductors in the entryways. In stratified geologies, a transverse electromagnetic (TEM) mode of signal propagation is possible if a low conducting layer is bounded above and below by higher conducting layers. In general, the difference in conductivities must be at least several orders of magnitude. Such geological waveguide conditions often exist in underground mines. Propagation via the waveguide effect is known as the "seam mode" of propagation. Another mode of propagation, the "tunnel mode," exists in underground entries with electrical conductors such as power cables, metal pipes, and phone lines. A monofilar mode of propagation exists when signals are impressed upon conductors and return via the surrounding rock. A bifilar mode of propagation exists when all signals exist only on local conductors. In a given location there is a combination of monofilar and bifilar modes that make possible an interaction between the conductors and a transmitting device in a tunnel or entryway. Signals can be impressed on or received from local conductors via magnetic dipole antennas (loops) or line couplers.

By E. H. Christiansen

Gem-quality red beryl in the Wah Wah Mountains of southwestern Utah formed as a post-magmatic mineral in a topaz rhyolite flow. Unlike topaz, this beryl occurs along fractures in devitrified rhyolite, rather than in lithophysal vugs. The flow occupies a graben and perhaps a significant paleo-drainage. Beryl occurs at medial depths within the eroded flow, about 170 m below overlying mafic lava flows. Both beryl-bearing fractures and the host rhyolite show an unusual amount of argillic alteration compared with other topaz rhyolite flows. Alteration may be related to the incursion of surface water along shrinkage fractures within the flow. Whole-rock concentrations of CaO within the host rhyolite are very low (<0.01 % to 0.18%) compared with other topaz rhyolites and Be concentrations (about 20 ppm) are about average. Low Ca activities prevented fluorite precipitation and allowed Be transport as fluoride complexes. Beryl probably grew at subsolidus temperatures (-300-650°C), but above the temperature of kaolin development (200-300°C) as fluoride-rich vapors, released by devitrification, encountered fractures and mixed with vapors derived from surface water flowing through the fractures. Beryllium fluoride complexes reacted with water vapor, silica minerals, alkali feldspar, water, and Fe-Mn oxides along fractures to produce red beryl. Continued reaction of the cooling flow with surface water at lower temperatures probably produced a boiling, more acidic fluid that produced the argillic alteration. Consequently, eruption of low-Ca topaz rhyolite followed by entrance of surface water into medial portions of a devitrifying and still hot lava flow appear to be critical factors that led to red beryl formation.

Jan 1, 1996

Jan 1, 1911

By William J. Taylor

Strictly defined, a stull is an inclined or horizontal timber support; a vertically placed timber is defined as a prop. Common usage allows the catchall term "stull" to refer to all such uniaxial mine support, regardless of orientation. Typically a stull is a round wooden column that is wedged in place to provide short-term auxiliary support between sill and back, or between hanging wall and footwall. Stulls may be used exclusively or in con- junction with other support systems such as roof bolts, shotcrete, or cribbing. Stulls are used both as local temporary support in stoping operations and for uniform systematic support installations. Where stoping areas are to be abandoned soon after excavation, stulls may be used to provide temporary support during mining operations. Where controlled caving and subsidence is required, stull supports are designed to fail in a systematic, predictable manner. Wood type is selected on the basis of availability, price, and load carrying characteristics. Coniferous woods are typically used, especially to carry heavy ground loads. Brittle woods are generally avoided because of their tendency to fail suddenly. Gradual yielding failure is preferable to sudden, unexpected failure of the support. Some usage of wood from deciduous trees such as cottonwood and other poplars has been reported in Grants, NM. These stulls reportedly mushroomed as the ground load increased but continued to maintain their structural integrity. Stulls fabricated from structural steel are used in special applications. Adjustable lengths are commercially available in mechanical, hydraulic, and pneumatic designs. The high cost of mechanical stulls limits their use to mining systems where recovery and reuse is possible. End blocking, also called headboards or footboards, uses wood blocks that are placed between the stull end and the ground they are supporting. The blocks are typically 50.8 to 101.6 mm (2 to 4 in.) thick, 203.2 to 304.8 mm (8 to 12 in.) wide, and 381 to 609.6 mm (15 to 24 in.) long. End blocking serves to distribute the support over wider back area. Compression of the end blocking gives visual indication of wall movement prior to failure of the stull. A common application of the stull is in flat-bedded uranium mining during pillar extraction. Many western US uranium mines use a pillar pattern development to delineate the irregular ore pods. After development of an appropriate sized pillar, the ore pillars are then sequentially mined out, leaving the undercut hanging wall or back to cave. Where thickness of the ore is less than 4.3 m (14 ft), stulls are generally used to provide ground control as the pillar is removed in slices. Experience dictates the density of stull placement. In general, the number and size of stulls should be sufficient to resist ground closure and to provide support for drilling and loading operations adjacent to the pillar. Stulls next to the mining face are often lagged 0.9 to 1.2 m (3 or 4 ft) up from the floor (or sill) to confine the blasted ore to a passage next to the pillar. Mucking is simplified by this confinement. Experience dictates whether back control along a mining face requires removal of stulls to allow con- trolled subsidence of the back or hanging wall. Without caving or closure, abutment pressure can create poor ground conditions near the pillar.

Jan 1, 1982

Develop new technolgies and techniques which enable recovery of strategic and critical minerals such as cobalt from domestic resources, thereby easing the U.S. dependence upon foreign producers for these valuable commodities. Approach The Bureau of Mines, through research, developed a process which uses mineral beneficiation techniques to recover cobalt-rich products from Missouri lead ores. Before development of this process, cobalt was lost as an impurity in the copper, lead, and zinc concentrates and in the mill tailings because the technology to recover it with minimum impact on present production did not exist.

Jan 1, 1989

By M. M. Fine

Development of a process for winning copper from pelletized chalcocite concentrate without matte smelting and converting is underway at the Twin Cities Metallurgy Research Center, Bureau of Mines. The new route from concentrate to metal includes 2-stage fluid-bed treatment; pelletized concentrate (33 percent Cu, 7 percent S) is first desulfurized (to about 0.5 percent S) in an oxidizing atmosphere, and in the second stage the calcine is metallized by reduction with hydrogen. Thereafter, the reduced product plus 10 percent CaO is routed to a smelting furnace to separate metallic copper from the gangue. Recovery and the Cu content of the product at this point are in the 97-98 percent range. The metal must be refined to remove sulfur and iron to make wirebar copper. An important feature of the process is the pelletizing of the fine concentrate into mini-pellets prior to fluid-bed treatment, which has permitted shorter reaction time, decreased dusting, and facilitated subsequent processing.

Jan 1, 1970

By George B. Griswold

The two most stringent parameters for in place fracturing of rock are the lack of any initial void space in the rock which to expand into and the ability to gain access only through drill holes. These two restrictions have proven so severe that as of today the only proven techniques for efficient fracturing are the contained nuclear detonation and hydrofracing. Both of these methods have highly developed technologies for their application. Hydrofracing has been a standard oil field practice for two decades, and the experience gained from a couple hundred underground nuclear detonations has resulted in a thorough understanding of the phenomenology of cavity and chimney formation. What is still lacking is a practical method to create a suit- able degree of fracturing for those ore bodies which do not meet the application criteria for either the nuclear explosion or hydrofracing. Nuclear applications must be restricted to thick ore deposits so as to take advantage of chimney collapse height--preferable in excess of 200 feet thick. Other requirements such as ground shock, containment, and radioactive contamination further reduce the number of sites that prudently can be selected.

Jan 1, 1969

By Susanne Pignolet, Richard D. Hagni

Ore microscopy has been applied to the complex cobalt-nickel- copper-lead-zinc ores from the Madison Mine in the Fredericktown subdistrict of the Southeast Missouri Lead District to predict potential beneficiation problems. It has been found that in some portions of the ore deposit, textures are present which may result in metal losses. In ores from the Bonneterre Transition Zone the intimate association of siegenite with chalcopyrite may result in cobalt and nickel losses to the copper concentrate and nickel contamination of the copper matte at the smelter. In ores from high stratigraphic horizons, this association is relatively uncommon, and siegenite is commonly associated with bravoite. This latter association will increase the the recovery of cobalt and nickel in the siegenite concentrate. However some cobalt and nickel will be lost to the tails as bravoite-pyrite particles due to the intimate intergrowth of these minerals. Other textures which may result in beneficiation problems include the intimate intergrowth of chalcopyrite and galena and the occurrence of sphalerite as inclusions in galena.

Jan 1, 1984

By Peter Amelunxen, Craig Lockhart

Significant effort was made in 2003 and 2004 to upgrade the existing instrumentation and process control infrastructure at the Phelps Dodge Bagdad copper concentrator. Specifically, • cameras were installed on the feed belt for online image analysis data, • ultrasonic level sensors were installed for froth height and sump level control, • a trial froth image system was installed on one of the rougher rows, and • a new expert system to tie everything together was integrated and tuned in-house. Control philosophy, observations, opinions, and general tips and tricks are discussed with the hope of assisting other plant personnel and expert system integrators.

Jan 1, 2005

Macraes Mining Company Limited operates a 2.1 million tonnes per annum gold processing plant at Macraes Flat, Otago. This uses a conventional CIL route to treat oxide ore, and a flotation, grind, CIL route for sulfide ore. This paper describes the design and operation of this process plant.

Jan 1, 1992

By Michael S. Robinson, Serge Moalli

Construction of the CSO Retention - Treatment Tunnel, Segment 1 in Dearborn, Michigan includes excavation for an overflow Structure with a minimum inside diameter of 15.24 m (finished). The excavation extends downward through overburden soil including a 15.2 m thick zone of potentially weak clay. This paper presents the subsurface data for the clay and a geotechnical analysis thereof, together with predictions of the behavior of the planned 15.54 m inside diameter open end caisson as it is sunk through this potentially weak zone. In a companion paper, the writers will compare the behavior observed with that predicted.

Jan 1, 1995

PRESIDENT WHITESIDE: The chair will now throw the meeting open to discussion. GEO. B. PRYDE: In the old days at Rock Springs we had electric plants situated about half a mile from our mines; we had small boiler plants; we had an electric plant with about 600 kilowatt capacity. About ten years ago we discarded the old steam plants and started building towards a centralized power plant. We now have three 2,500-kilowatt turbine generators and one 1,000, and our peak load is about 7,000 kilowatts. We have had to rebuild the old power plant, scrap the old machines, and install water tube boilers. We did this as a matter of economy in a small local plant we had years ago, and it has grown to be a large central plant, supplying power for about 20,000 tons of coal daily, and distributing this power within a radius of twenty miles. We have found this method of power to be more economical than with the old plants, and the people who buy power from us in the Rock Springs field say it has been to their advantage also. We found this last year, when we had to shut down for five months, that that plant was the only plant operating in the Rock Springs field, supplying all the power, running of fans and pumping during the time the mines were shut down, and it helped the situation very much. We had an old wooden building which we had to tear down, raise the walls, and put on a steel roof; had to rebuild the boiler room and rebuild the boilers. The water situation at Rock Springs has never been very good; we get our water from wells 250 to 500 feet deep, and use one and one-quarter million gallons a week. We have two large spray ponds and we have gotten along well. There isn&apos;t any comparison between the central power station and the old method of making power. (Applause.) FRANK YOUNG: I listened with a great deal of pleasure to the paper just read, and it struck me it was remarkable how a paper prepared by anyone could be so nearly identical and coincide so very near with the experience of another. It is just like some work I have had. I had the engineering part to do for the power plant for ten years, and I think at that time we did all of the things that he mentioned in his paper. Also his analysis of the cost of power seems to me exactly right. If I had gathered the figures and made the statement myself I think it would have been very much the same as was read. The recommendation that it is better to buy

Jan 1, 1923

By J. R. Caylor

The Mine Safety and Health Administration (MSHA) advanced several initiatives last year to further protect miners&apos; health. Regulatory efforts included the implementation of a Hazard Communication rule for all mines, work on the Single Sample rule for all coal mines, and the Plan Verification rule for underground coalmines. Development and application of new technologies are actively encouraged in preventing miners&apos; hearing loss and respirable dust overexposures. MSHA&apos;s successful x-ray program for screening of black lung among coal miners completed its third year. Compliance Assistance efforts are focused on Best Practices, outreach, and technical support for operators&apos; specific challenges.

Jan 1, 2003

Both the miner and the Regional Water Board have legal obligations to ensure that all discharges of water from a mine site are free of harmful wastes, and that proper authorisation is obtained to abstract, divert, or discharge water. This requires long-term planning of water management for the whole of the mine site. Guidance is given in the paper on the issues which must be covered in water right applications.

Jan 1, 1986

By Philip J. Daynes

As part of the regeneration of the centre of Dublin, a multi-functional development is being constructed on the site of the historic Smithfield Fruit Market. The site is being developed in three phases, and includes one of the deepest basements (10m) constructed in Ireland to date. Until the recent improved economic climate, there has been little requirement for deep basements in Dublin, and this is the first to be constructed entirely within fluvio-glacial gravels and boulders. The difficult ground conditions led to the adoption of a diaphragm wall solution to ensure a watertight construction. Tie-back anchorages are utilised in the temporary case, and the wall is propped by floor slabs in the permanent case. Where required by high bedrock levels, the diaphragm wall is dowelled into limestone bedrock to ensure toe stability. The recorded lateral movement of the wall is significantly below that calculated by numerical analysis. Temporary bentonite cut-off walls were installed to divide the site into discrete sections. The basement was constructed as a tanked structure, and is subject to uplift water pressure. Passive tension minipiles provides an innovative alternative to the standard stressed anchorage solution. This paper describes:- design and construction aspects of the diaphragm wall, tie-back anchorages, and anti-flotation minipiles, together with recorded lateral wall movements,

Jan 1, 2003

By Charles B. Carpenter

[The Bureau of Mines selected Anahuac for a petroleum-engineering study because it is one of the notable fields of the Gulf Coast region. It is outstanding because the producing for is very thick; every modern technique of drilling&apos; and development has been applied; complete records of all operations,, including detailed subsurface information have been kept; the field has been developed systematically; and every effort has been made to utilize the reservoir energy efficiently Data and information pertaining to the development anal operation were collected, compiled, and studied by the writers as if the field were under single ownership. The chief aim-of the stud,, was to increase the accuracy of the existing methods of estimating reserves by applying all the data collected during the modern development of an oil-field, These scientific aids include coring; electric logging; micropaleontology determinations of porosity, permeability of oil-bearing sands, and their connate water content; subsurface sampling of the reservoir oil; and depth-pressure measurements. Because the reservoir structure in the Anahuac field is extremely complex, special attention was given to methods of calculating the reservoir volume.]

Jan 1, 1941

By K. Gorazda

The population growth, urban and industry development cause the increased pollution with different substances, which contain phosphorus. It contributes to the increased demand for its compounds, increasing the use of its natural resources, which is considered to be the most accessible source. The forecasts regarding the world natural reserves of phosphorus deposits are saying that more than 50% of resources used currently will be exhausted within next 60-70 years (Steen, 1998). European Union formulated its goals regarding the waste management in 1990. Its main rules include prevention of waste generation, recycling, reuse of waste as the raw materials in technological processes, separate collection and optimization of final removal. The phosphorus recovery from waste is realized currently in many ways: directly from the waste water stream in sewage-treatment plant, from the sewage sludge, from animal waste, industrial waste and other emissions from industry (Przewrocki et al., 2004). According to the rules of cleaner production the waste should be treated as the source of resources for the production of products with full value (Kowalski, 1998).

Jan 1, 2005

By Irving Palmer

DURING the past 15 years in this country there have been few additions to the literature of lead smelting. After the consolidation of the principal smelting companies at the beginning of this period it became the policy of the larger company not to permit the publication of details in regard to many of its metallurgical processes. This led to similar action on the part of some of its competitors. The result, of course, was a decided decrease in the number of papers written upon the practical side of the subject. Even upon the theoretical side the contributions have been few. It would seem that the industry as a whole has suffered from this general unwillingness to exchange information. While it is true that a given company is entitled to the reward that may come from its own development of a new process, it is also true that a still greater reward might be the result of a free exchange of ideas with other plants. This principle has been recognized for a long time in other metallurgical industries, notably those engaged in the smelting of iron and the manufacture of steel. It is pleasing to note that the leading lead-smelting company has very recently decided to modify its policy of secrecy, and to permit the publication of papers covering some details of its metallurgical methods. The statement has been made that there has been but little progress in lead smelting during the period just referred to. This impression is due in part to the scarcity of papers written on the subject. There has been, it is true, some discussion of the new sintering processes, but with little reference to detail, and to the effect that blast roasting has had upon the industry as a whole. In spite of the prevailing belief, it may be said that lead smelting, in common with other metallurgical industries, has made steady and substantial progress. It is the purpose of the present paper to discuss briefly some features of the industry as it is now conducted, with special reference to the blast-furnace practice in the larger silver-lead smelting plants of the United States and Mexico.

Jan 7, 1914