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By Derek Ellis

Volume II of this two-part series on Submarine Tailings Disposal (STD) as a tailings management option for coastal and island mines contains descriptions of lesser known case histories. The Misima gold mine (Papua New Guinea) and the Black Angel lead-zinc mine (Greenland) are described in some detail as the best documented cases. Atlas copper mine (The Philippines) is less fully described due to relative lack of documentation. The Misima and Atlas STD systems are working to their design criteria. At Black Angel the system adopted did not prevent contamination for a number of reasons, which are now understood. Two cases are described where STD is being developed. They are the Cayeli Bakir copper mine Turkey), and the Toquepala and Cuajone mines (Peru). There is excellent documentation available for both cases. Three case histories are described where tailings have reached the sea either through beach or river discharge. In one case the STD option has been explored (Marcopper Mine, The Philippines). In the others we explore in hindsight whether STD might have been a viable alternative using the Screening Criteria that this Volume develops - see below. The mines are Bougainville Copper Mine in Papua New Guinea, and Jordan River Mine (Canada). There is potential for STD at all three sites. Finally, the Volume presents Screening Criteria for appraising STD, based on the experience in design, operation and environmental impact reviewed in the case histories.

Jan 1, 1994

By Lloyd Williams

1. The investigation shows that the Coal Creek has been the most productive, bed in Campbell County and contains the largest recoverable reserves of coal. The Pewee, Red Ash, and Jullico have been relatively productive beds and contain appreciable recoverable reserves of coal. The Blue Gem also has been productive in the past, but available information indicates that most of the remaining coal is Less than 28 inches thick. The Big Mary has relatively large reserves over 28 inches thick, but the coal is high in ash and sulfur. Thick partings in the Windrock bed have discouraged mining in that bed. The Poplar Creek and Rex beds generally are below drainage, and large areas have been excluded from the reserve estimate, Reserves in the Walnut Mountain bed will be difficult to mine due to the irregu¬lar thickness and lack of continuity of the bed. Estimated coal reserves are- small in the remaining five beds. 2. Known measured and indicated reserves of coal, based on a minimum bed thickness of 14 inches and on 1,800 short tons per acre-Foot of coal in place, are estimated to be 398 million tons as of January 1, 1953, o? this total, 267 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, these should be added to the total estimated reserves.

Jan 1, 1956

By Robert W. Waytulonis

The Federal Bureau of Mines contacted 29 organizations--mine maintenance departments and equipment manufacturers--concerning service experience and construction of diesel exhaust-gas water scrubbers. Scrubbers are used primarily on mobile diesel-powered mining equipment subject to 30 CFR 36. Because the scrubbers cool exhaust gas and act as flame arresters, their failure would compromise safety in underground mines. Scrubber maintenance problems and frequency and modes of failure were identified, and construction materials and techniques were evaluated. Three failed scrubbers were randomly selected from two cooperating mines, and their modes of failure were determined. In conjunction with failure analyses, mine water and scrubber water solution samples were chemically analyzed to characterize corrosive properties. Sludge and mineral deposits and different types of corrosion and metal fatigue were identified as problems leading to scrubber failure. The corrosion process is explained; maintenance practices, construction materials, and manufacturing methods that could be used to reduce premature failures and allow longer effective scrubber life are identified; and basic changes in scrubber design are suggested. If type 304 stainless steel is used throughout the scrubber and regular maintenance is performed, long, dependable service can be expected. Other materials such as 304L, 316, or other more exotic steel alloys may be necessary under certain conditions.

Jan 1, 1982

By William C. Cooley

This study Identifies and evaluates deposits of noncoal minerals in the U.S. which are most amenable to be mined underground hydraulically and transported hydraulically. A method was developed to screen and compare mineral deposits including economic comparisons. The most applicable minerals for hydraulic mining by borehole monitor jets from underground entries are soft uranium sandstones In Wyoming in locations where water is available. This method with hydrotransport could improve the safety, health and economy of underground uranium mining. Soft oil-bearing sandstones in California and Texas could be mined and transported by this method more safely than by other underground mining methods. Other weak sandstones may be hydraulically mined economically. Man, minerals are too hard to be mined by monitor jet but are amenable to hydraulic transport and hoisting. Uranium sandstone in New Mexico is of interest because of potentially improved health and safety in transport and lower transport cost, Increases in mine output for potash, in New Mexico and trona in Wyoming can be achieved most economically by adding hydraulic hoisting when existing skip capacity is at its limit. Research is recommended to obtain site-specific data on the feasibility of mining uranium ores by monitor jets.

Jan 1, 1981

By D. K. Steele

An 18-in-diam column water elutriator was designed, tested, and operated by the Bureau of Mines for recovering nonferrous mixed metals from automobile shredder rejects. The waver elutriator separated metals from nonmetals contained in shredded nonmagnetic rejects. The unit was constructed and integrated into a local automobile shredding operation. Nonmagnetic rejects from the automobile shredder were fed onto the surface of a column of rising water. Dense materials fell through the rising water and were collected as a sink product at the bottom of the column; medium-density materials were removed as an intermediate product in a water flow through a discharge port located between the overflow and sink; and light materials were immediately carried out in the overflowing water at the top of the column as a float product. Nearly 99 pct of the mixed metals were recovered from the nonmagnetic rejects as a 70-pct-metal concentrate. Other operating conditions yielded a 93.7-pct-pure-metal product resulting in a 93.1-pct metal recovery. Float rejects are combustibles, light plastics, foam rubber, and minimal amounts of coated and uncoated copper wire. The middling discharge contained mainly medium-density rubber, plastics, glass, rock, coated and uncoated copper wire, and frequently some thin-sheet stainless steel and wrought aluminum. Maximum metal recovery in the operating program was achieved using a water velocity of 52 fpm (650 gpm). Maximum purity was obtained with a velocity of 88 fpm (1,100 gpm). .Water was recycled through a 12,000-gal baffled clarifying tank. Entrainment water losses with the float and middling rejects averaged 50 gpt of reject feed. Records maintained by the shredder operator show a 34-pct increase in nonmagnetic metals recovery during a 1-yr operation of the water elutriator as compared to recoveries from a previously used air classification system.

Jan 1, 1983

By Andrew Cecala

The Bureau of Mines performed tests to compare the effectiveness of steam and of water sprays to reduce respirable dust levels at mineral processing plants. By applying 0.22 wt pct water vapor as steam to product material, a 64-pct respirable dust reduction was recorded. By applying the same amount of moisture with water sprays, only a 25-pct dust reduction was recorded. By increasing the moisture content up to0.5 pct using water sprays, the dust reduction was increased to 55 pet, which was still less than the dust reduction achieved by adding less than half that amount of water in the form of steam.

Jan 1, 1985

By Gustav Wirth

"ABSTRACTIn exothermic and endothermic catalytic reactions, control of the temperature is of utmost importance. Basic calculations are developed for determining catalyst volumes of various types of reactors that give particular temperature distributions, and the individual designs are compared.INTRODUCTIONA narrow range of permissible operating temperatures characterizes many, catalytic reactions, and yields of the desired product are reduced sharply if operating temperatures fall outside of this optimum range. In order to achieve close temperature control, reactors with internal heat exchange have been developed in which thin layers of catalyst are located between cooling surfaces.The temperature distribution for an exothermic reaction in such a thin catalyst layer is shown in figure 1. Reactive gases flow downward through the catalyst section, which is 2so wide. It is assumed that a constant amount of heat is generated per unit of bulk catalyst volume, and that this heat is entirely removed through the walls. Consequently, except for a short section at the entrance of the reactor, the heat of reaction is not available for raising the temperature of the gases. Thus, at all points equidistant from the axis, the temperature is the same throughout the entire reactor. At the middle of the gas stream, the temperature is designated as uo. Traveling radially from this point, the temperature decreases because of the removal of heat through the walls and reaches, in the vicinity of the cooling surface, the value u1. Over a relatively narrow zone of width, b, the temperature falls to the value u2 at the cooling surface. Because inadequate data are available on heat-transfer coefficients for a gas flowing through a porous bed, and also because the narrow zone, b, is probably without effect on the reaction by virtue of its low temperature, the temperature drop in this zone at the cooling wall was disregarded. The following calculations were made on the basis of the temperature drop (u0 - u1) resulting from heat conduction within the main body of the catalyst bed only."

Nov 1, 1950

By Carl R. Peterson

[In lTI n,v und I'gr'oun nllnin~ Opt'I'ali n' the high . t cost is the loading and I 3ulage of t tln-of -D"'line ot'. 01' hauling costs can be r duced signifi-cant\v with the us ~ (r \) >It corn'e)'OI' " a COnlTllOn pl'acti c i.n coal and other s 0 t'L rn I n r' a l III i, n e , '. Jf 0 vel s i z ' () f' e can bee 1 i 11.11 tl ate I rH'i 0 I' lO C n v e . in g, ]

Jan 1, 1976

The objective of this study was two-fold: 1. To perform a world literature search pertinent to the analysis, selection and design of hoisting systems and their components and to codify the search into a literature compendium. The search resulted in a technical data file of over 1500 hard copy items. The compendium index was also suitable for establishing a comprehensive computer-loaded data base on the subject. 2. To develop a comprehensive system of guidelines to cover salient aspects of analysis, selection and design of electrical, mechanical and structural components of a hoisting system with a view to establish parameters for maximum safety and efficiency of operation, installation and revision of the system. 3. (a) The system design of hydrostatic drives for mine hoists, usually of special nature, is considered along with oil hydraulic component selection suitable for the application; (b) The criteria for head frames of steel and/or concrete are developed with full consideration of all operating and environmental conditions.

Jan 1, 1988

By J. S. Stachulak, G. H. Schnakenberg

The objective of the Diesel Emissions Evaluation Program (DEEP)-sponsored project at Inco's Stobie mine was to conduct a long term field evaluation of diesel particulate filter (DPF) systems available to the underground mining industry. Some of the major issues studied were criteria for selecting the filter media, means of DPF regeneration, efficiency of DPF systems and the occurrence of unwanted secondary emissions, and reliability and durability of DPF systems. Nine state-of-the-art diesel particulate matter (DPM) filtration systems have been retrofitted to heavy-duty and light-duty vehicles and have been subjected to extensive long-term in-mine evaluation. Periodic efficiency tests were conducted at various stages of the study (2001, 2002 and 2004) to establish in-use efficiencies and durability of the tested DPF systems. The results were used to assess the effects of the filter systems on the concentrations of particulate matter, nitric oxide, nitrogen dioxide and carbon monoxide in the vehicle exhaust. The variety of filtration systems and regeneration concepts used in this study offered the opportunity to investigate their advantages and disadvantages. This paper also offers a review of selected experiences with the installation and operation of the DPF systems on underground mining vehicles at the Inco Stobie Mine.

The small-scale surface mining operation in northern regions is typically located in a remote, ungaged basin. With the recent increase in the economic potential of mining, the number of small operations is increasing. The year-to-year variability in precipitation in this region under study is of great concern to mine operators. Some years may yield only 5 to 6 inches of precipitation, while others may yield in excess of 15 inches. Such variability makes placer mining operations difficult to plan, since low water years may result in too little run-off for gravel washing and high water years may result in flooding of mining developments. There are no official streamfloaw records in many watersheds in the northern region containing placer mining claims. However, information from other streams permits calculation of an estimated discharge for a watershed under consideration using average flows per square mile of drainage. It is to be emphasized that these are average or expected figures in reality, one water year may be significantly wetter or drier than another. This high variability of annual precipitation is significant in relation to placer operations because of the large quantities of water required for this type of mining. Some operations can not operate in low water years. In the larger watersheds, operations may continue in low water years but at a slower pace because of longer water collecting times. The high variability of available run-off rakes placer mining in many parts of Alaska difficult to plan on a long range because of the unpredictability of water supplies.

Jan 1, 1985

By Allan J. Clark

This paper, describing the milling practice of the Homestake Mining Co., is one of a series being prepared by the Bureau of Mines. The author acknowledges the assistance of T. G. Chapman, one of the consulting engineers of the Bureau of Mines, in arranging this paper for publication.

Jan 1, 1931

This report has been prepared in response to a request by the Bureau of Land Management (BLM) Fairbanks Alaska District Office that the Bureau of Mines quantitatively assess the potential supply of minerals from undiscovered deposits in the White Mountains National Recreation Area (WMNRA) and the western part of the North Steese National Conservation Area (SNCA) in Alaska. The assessment will be used to assist in future land-use decision-making. Resource Management Plans (RMPs) for the WMNRA and the SNCA were approved by the BLM in 1986. These plans imposed significant restrictions on new mineral development in the two areas. The level of public concern regarding these actions, especially on the part of the mining industry, has spurred BLM to seek additional information about the potential supply of minerals from the two areas with assistance from the Bureau of Mines. The assessment focuses on an area within the WMNRA and the SNCA which has been administratively closed to mineral entry. The study area encompassed approximately 1.24 million acres and included all of the WMNRA and the western portion of the North SNCA (fig. ES-1). Three quantitative estimates of the potential supply of minerals from the study area were developed: 1) For all lands in the study area, assuming that they are open to mineral entry-the baseline analysis; 2) For those lands which have been closed to mineral entry; and 3) For eleven prospective mineral activity areas, assuming that all are open to mineral entry.

Jan 1, 1989

By F. Sillers, R. T. C. Rasmussen

"INTRODUCTION This is the fourth report of investigations dealing with the cooperative tests between the Bureau of Mines and industry on the use of electrolytic manganese in steelmaking. The first report dealt with the use of electrolytic manganese in the manufacture of stainless steel 3/ the second with its use in acid electric steel practice, 4/ and the third with its use in low-carbon basic open-hearth steelmaking. 2/ A résumé of those investigations E7 appeared in the magazine STEEL. 5/ The present report deals with the use of electrolytic manganese in the manufacture of four types of stainless steel and the new Timken 16-25-6 alloy. The Bureau of Mines supplied The Timken Roller Bearing Co. with 62,000 pounds of electrolytic manganese for use in the tests.The electrolytic manganese was produced at the Bureau of Mines pilot plant, Boulder City, Nev., by the process developed by the Bureau and described in Bulletin 463, Operation of Electrolytic Manganese Pilot Plant, Boulder City, Nev., by J. H. Jacobs. J. W. Hunter, W. H. Yarroll, P. E. Churchward, R. G. Knickerbocker, R. W. Lewis, H.A. Heller, and J. H. Linck. The workcarried out under the direction of R. S. Dean, formerly assistant director, Bureau of Mines, and R. G. Knickerbocker, formerly chief, metallurgical branch, as part of a long-range program involving the development, manufacture, and use of manganese from domestic ores. Preliminary arrangements for the plant tests were made by the late A. A. Dow. 7/"

Jun 1, 1947

By Charles B. Carpenter

The New Hope field was selected for study by; Bureau of lanes engineers because many problems met by, the operators during development and operation were unique to petroleum-engineering experience. Solving these problems is believed to have doubled the ultimate recovery of oil from the field. Since the discovery well was 'completed, in April 1943, an oil-productive area of 4,950 acres- has been delineated by the drilling of 64 wells, four of which were dry holes. Four oil-bearing reservoirs - the Bacon oolitic limestone, and the Hill, Pittsburg) and Elledge sandstones, all, in the Trinity group of the Lower Cretaceous series-- have been penetrated at depths ranging from 7,300 to 8,100 feet. Three of these reservoirs were found to be closed-type or solution gas-drive reservoirs, and one - the Hill - was an open-type or water-drive reservoir. During the course of the study, the Tide Water Associated, Oil Co. and -Seaboard al Co. of Delaware made available to the writers all well records, electric logs; and coring, production,, and pressure data. The ,writers performed Certain field and laboratory- tests on cores of ,the reservoir racks and' samples -of the reservoir Oils. Analyses of cores from the four reservoirs showed average .porosities ranging from 10 to 18 percent, average permeabilities of 17 to 297 millidarcys, and -average 'connate water contents ranging from 25.4 to 30.6 percent. Subsurface and recombined samples of reservoir oils indicated that the oils in the Bacon Hill, and Pittsburg reservoirs contained ,206 to 422 cubic feet of gas in solution per barrel initially, and that the, reservoir oils were undersaturated with gas. No samples' of oil from the Elledge reservoir were analyzed, and because of meager data this reservoir was not studied in detail. 4 The presence of free 'gas' or a' gas cap, however, indicated that the oil in the Elledge reservoir was saturated with gas. The rapid decline in pressures in- the' four reservoirs during the 'first year of operation alarmed the operators and provoked them to investigate the reservoir conditions to determine the cause.

Jan 1, 1949

By J. C. Fowler

The field testing of the Seismic Mine Monitor System is described. This system consists of nine geophones buried about 40 feet deep over a ten-square-mile area, the amplifiers and electronics needed to get the signals to the mine office, and a central processor unit to detect and locate explosions and large roof falls. Since the problems associated with the original installation were solved, this system has worked for 2 1/2 months. The system has detected roof falls in the pillar areas and has located blasts as small as 114 pound of dynamite. The location accuracy has, in general, been within 250 feet. The system is now being used to gather long-term data on the seismic activity of the mine.

Jan 1, 1974

By W. S. Sanner

Anthracite was used extensively as a fuel in iron metallurgy from 1840 to 1880. In 1874, 226 of the 680 blast furnaces in the United States were operating on anthracite and producing almost one-half of the Nation's pig iron. However, by 1890, railroad expansion, the development of western iron-ore reserves, and the growing use of coke decreased the importance of anthracite as a metallurgical fuel. As a result, the last blast furnace designed exclusively for anthracite use was built in 1891. Because of the increased energy requirements of our expanding national economy, the abnormally high demands during national emergencies, and the proximity of anthracite deposits to eastern steel-producing areas, interest has grown in again using anthracite in iron metallurgy. Estimates of anthracite reserves indicate a 300-yr. supply at a production rate of 30 million tons per year. These large reserves dictate the development of an adequate technology for the use of anthracite by the metallurgical industry.

Jan 1, 1961

By Phillip R. Moyle

A cobalt/manganese occurrence in Clark County, Nevada was the subject of a site-specific mineral investigation by the U.S. Bureau of Mines in 1988-90. The study site is in the northern part of the Million Hills (wilderness) study area which is administered by the Bureau of Land Management. Field work during a period of one week consisted of geological mapping and sampling of workings and outcrops, and geochemical and geophysical surveys conducted on four transects totalling 7,600 ft. Although the concentrations of cobalt (0.1 to 0.5 percent) detected in samples from the fissure zones are within the range of grades associated with world-class economic deposits, the volume of material enriched in cobalt at the study site is insufficient to warrant consideration as a potential resource. Concentrations of manganese, nickel, copper, lead, zinc, barium, and thallium, although anomalous, are too low for economic consideration. At the study site, workings consist of three trenches and nine pits. The exploration history is unknown, and no production is reported.

Jan 1, 1990

By George S. Rice

In 1911 the Director of the United States Bureau of Mines instructed the chief mining engineer of the bureau , during an investigation of coal-mine safety conditions in Europe, to ask the directors of the various mine-experiment stations whether they would favor a European conference . The majority of the officials in immediate charge of experiment stations favored the plan , and Victor Watteyne, inspector general of Belgium, suggested that the United States call such a conference to be held immediately after the Eighth International Congress of Applied Chemistry, which was to assemble in New York on September 3, 1912 . Accordingly, invitations were issued by the United States Government to those countries having mine-experiment stations , namely, Austria-Hungary, Belgium, France, Germany , and Great Britain, and to those that contemplated the establishment of such stations , Canada and Mexico . All but Great Britain and Canada accepted ; Mexico designated a representative , who later found it impossible to come. The Government of Great Britain in declining, expressed regret at its inability to accept ; an informal statement was made that the opening of the experimental gallery at Eskmeals , England , occupied the attention of the officials in charge . Delegates were appointed by their respective Governments as follows: Austria-Hungary, Julian Czaplinski , royal mining engineer. Belgium, Victor Watteyne , inspector general of mines . France, J. Taffanel, director of the Lievin experiment station . Germany, Carl Beyling, bergassessor, director of Dortmund experiment station. United States , Charles E. Munroe, consulting explosives expert and George S. Rice, chief mining engineer of the Bureau of Mines . Subsequently Mr. William O'Connor , a mining engineer and mine operator of Wales , who opportunely appeared at the Pittsburgh station with letters of introduction from the South Wales Institute of Engineers and from prominent mining officials of Great Britain , was unanimously invited to take part in the meeting as an unofficial representative of Great Britain . Messrs . Beyling, Taffanel , and Watteyne were met in New York on September 3, by George S. Rice, who accompanied them to Washington, where they were welcomed by Director J. A. Holmes , of the Bureau of Mines , and where , with the delegates to the Eighth International Congress of Applied Chemistry , they were presented to President Taft . Mr. Taffanel was unfortunately called back to France just before the scheduled time of the conference on account of a mine disaster ; the other delegates , including Mr. Czaplinski , convened at Pittsburgh on the morning of September 14. Mr. Rice, representing the Director of the Bureau of Mines , acted as temporary chairman , and called the meeting to order.

Jan 1, 1914

By L. A. Morely

Volume II of the final report concerns the application of sensitive ground-fault interrupters (GFIs) to ac utilization circuits in U.S. mines The main concepts examined are shock prevention and methods for reducing nuisance tripping. The research involved a literature search, input from previous Bureau of Mines contracts, and contacts with electrical manufac-turers and mining personnel. Following this background work, several devices that showed promise were obtained and tested. Results of testing indicate the existence of GFIs that may be modified to perform adequately on U.S. mining systems. A recommended set of guidelines is included in the report, covering design, construction specifications, and performance tests.

Jan 1, 1982