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By Joseph M. Kurtak

The Bureau of Mines (Bureau) and the U.S. Geological Survey (USGS) conducted a 4-year (1979-1982) mineral assessment study of the Chugach National Forest (CNF), Ak, as part of the Roadless Area Review and Evaluation (RARE II) Program. The USGS remapped the geology and distribution of mineral resources. The Bureau investigated mines, prospects, and mineral occurrences. This report describes the results of Bureau work in the central 790,880 acres of the Forest. Copper, with by-product zinc, silver, and gold, has been the major metal produced from the study area as well as from the entire Chugach National Forest. The majority of the copper deposits are concentrated within basaltic rocks on Knight Island but the major producers are hosted by sedimentary rocks on Latouche Island. Approximately 182.6 million lb of copper, 1.5 million oz of silver, and an unknown but substantial amount of gold were produced during a 30 year period. Currently no mines in the area are producing. Inferred, indicated and measured reserves having mineral development potential total 4.6 million tons, with weighted average grades of 1.6% copper, 0.30 oz silver/ton, and 0.04 oz gold/ton.

Jan 1, 2011

By Keith L. Harris

Recent data indicate a marginal decline in overall growth in world economic output from 3.1% in 1985 to 2.9% in 1986 (table 1),2, 3 Many nations experienced slower economic growth because of the huge trade imbalances existing between the United [ ] States and Japan and the Federal Republic of Germany, the U.S. budget deficit, and the growing Third World debt. Some developing nations, however, experienced booming growth. Declining prices for energy and nonenergy commodities and the fall of the dollar against the currencies of major industrial countries benefited several developing countries--energy importers and exporters of manufactured goods with currencies tied to the U.S. dollar, which were able to expand markets in the industrialized nations. The drop in commodity prices increased demand in industrial countries and depressed it in developing countries. Lower demand in the developing countries contributed to a decline in the real net exports from industrial countries. As a result, output growth in industrial countries declined from 3.0% in 1985 to 2.4% in 1986, despite growing internal demand, Average output growth of developing countries increased from 3.296 to 3.596 during the same period, however, primarily because of the low prices of their products and the strength of demand in industrial countries for those products. Developed country output growth was extremely uneven, however. For example, the economic output of nonfuel exporters grew 5.4% in 1986, while that of fuel exporters dropped 0.7%.

Jan 1, 1987

1. Domestic Production and Use: In 1979, 12 companies operated 32 primary aluminum reduction plants, with 3 firms accounting for 64% of production. Washington, Oregon and Montana accounted for 32% of the total production; Gulf Coast States 20%; other Northern States 32%; and other Southern States 16%. Based on published producer prices output of primary metal in 1979 was valued at over $6 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1979, building accounted for about 24%; packaging 23%; transportation 22%; electrical 11%; consumer durables 8%; and other uses, 12%.

Jan 1, 1980

By J. J. Forbes

Problems connected with the incidence, effects, determination, and control of dusts are still much before the public, although more information is available to the layman than when Bulletin 400, of which this publication is a revision,5 was issued in 1937. Bulletin 400 attempted to assemble information in convenient form on various phases of the dust problem, largely in the mining and allied industries. This revision includes data that have accumulated since 1937 and some that appeared previous thereto but were not available to the authors at that time. The literature on this subject is so voluminous that no attempt has been made to include all published material or all types of dust diseases, but only to assemble some of the more outstanding data on several aspects of the subject.

Jan 1, 1950

By R. W. Bee

This project, sponsored by the U.S. Bureau of Mines, Division of Environment, addresses two major subjects: refuse removal and subsidence monitoring. The refuse removal task consisted of developing a methodology for selecting the most economical combinations of coal mine breaker refuse and rock banks, disposal sites and material moving systems (trucks, trains, belt conveyers and pipelines). To prepare plans for moving refuse in the Lackawanna Valley of Northeastern Pennsylvania, refuse banks were inventoried, underground disposal sites identified and unit cost data prepared for the various material moving systems. The subsidence monitoring task consisted of defining the phenomenon of coal mine induced surface subsidence, establishing operational requirements, cataloging sensors and techniques to detect and measure subsidence and testing of the most promising techniques (photoelastic patch, tiltmeter, strain gage, microseismic and precise surveying). A preliminary system for a 700 acre area in Scranton utilizing 267 grid sensors, seven microseismic sensors and precise surveying techniques was designed with initial and annual operating costs determined. Two minor tasks supported both main subjects: zoning in the Northern Anthracite Field of Pennsylvania and Technology Transfer of subsidence vulnerability prediction techniques.

Jan 1, 1972

The U.S. economy and, consequently, the demand for minerals grew at more moderate rates in 1995 compared with stronger performances the previous year. Demand for metals such as steel and copper was relatively stable. For example, the decline in steel consumed in motor vehicle manufacturing (reflecting lower vehicle sales) for the first half of 1995 was offset by an increase in steel consumed in construction during the same period. More detailed information on events, trends, and issues in the mineral and material sector Is presented below and in the commodity sections that follow. Overall Performance The value of processed materials of mineral origin produced in the United States during 1995 was estimated to be $395 billion, an increase of almost 10% compared with 1994. The estimated value of U.S. raw nonfuel minerals production in 1995 was $38 billion, about 7% more than in 1994. The value of U.S. minerals production has increased in 30 of the last 35 years.

Jan 1, 1996

The mineral Industry, following the economy as a whole, experienced little growth in 1992. However, with modernized plants, efficient workforces, and lower operating costs, the industry is well positioned to take advantage of possible improvement in the national economy during 1993. In addition to the significant 1992 events highlighted below, important events, trends, and issues within individual mineral industries are addressed in the commodity sections that follow. The value of processed materials of mineral origin is estimated to have been about $310 billion in 1992. The value of U.S. raw nonfuel minerals production in 1992 is estimated at approximately $32 billion, a 3% increase over 1991. The value of domestic minerals production has increased in all but 4 of the last 32 years.

Jan 1, 1993

A compilation of papers presented at The Second WVU Conference on Coal Mine E1ectrotechnology in Morgantown, West Virginia on June 12 -14, 1974. Papers cover areas of electric power, electronic communications, detection and location of trapped miners, and electronic sensors and monitoring systems.

Jan 1, 1974

Federal Regulations require MESA to regulate the exposure of workers to inhalation hazards in the surface work areas of coal mining and processing operations. (1) The purposes of this study are listed below: 1. Determination of candidate inhalation contaminants for surface work areas of coal mining and processing operations. 2. Selection of appropriate sampling and analytical methods. 3. Performance of qualitative surveys of 56 representative coal mining and processing facilities. 4. Preparation of handbook to provide guidance for inspectors sampling for these contaminants. This report describes the work which was done to accumulate the information which was used in preparing the inspector's handbook. Specifically, this report contains descriptions of the surveys which were performed, analytical results obtained from these surveys, findings and conclusions, and recommendations for additional research.

Jan 1, 1975

By Oliver Bowles

In 1940 the Bureau of Mines issued a report describing all the cement plants of Latin America, their design, capacity, and output, and the cement imports, exports, and requirements of the several countries. Since that time there has been such great activity in cement plant construction that a revision of the paper is highly desirable. The present compilation comprises the essential data in the previous report together with descriptions of all cement plants completed, under construction, or planned since that date and an overall picture of the supply and requirement situation of each country. Before World War I, Latin America was one of the world's largest export markets for cement. Its dependence on outside sources created no special problems of supply until the shortage of shipping and abnormally high prices of the First World War stimulated a movement toward greater self-sufficiency. Under this incentive many cement plants were constructed, and several countries were able by 1939 to manufacture enough cement for their modest needs. Substantial imports were still required for many important areas, and as the volume of demand was rapidly increasing the Latin American countries as a whole were far from self-sufficient in cement when tine Second. World War began. South and Central America depended to a large extent on European countries, chiefly Germany arid Belgium and to a smaller degree Scandinavia, United Kingdom, France, and Italy, to Supply their cement shortages. The cost of manufacture in these European countries was much lower than in the United States, and transportation expense had been kept at a particularly low level because of the two-way trade that had been developed. Ships destined for Latin American ports for coffee, tropical woods; fruits, and other native products could carry cargoes of cement on their westward voyages at very low cost In some instanced cement was taken in exchange for South American -products because cash was not available. Great Britain had withdrawn from this market to quite an extent because of low prices and because trade with its own Empire had been increasingly fostered. United States trade in cement with Latin America had been confined principally to white and other special varieties. In few places could ordinary portland cement made in the United States compete in price with the European products; although in general it was of better quality and cool d be delivered more promptly.

Jan 1, 1946

1. Domestic Production and Use: Twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 66% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 25%; Northern States, 29%; and other Southern States, 14%. Output of primary metal in 1973 was valued at $2.2 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1972, building accounted for 28%; transportation 19%; electrical, 13%; packaging, 16%; and consumer durab1es, 10%.

Jan 1, 1974

By James T. McCartney, Joseph D. Davis

For more than 10 years coke-oven technologists have been investigating the expanding properties of coal on a scale larger than that afforded by laboratory test tubes. Koppers 4/ was among the first to realize that coals can not be differentiated satisfactorily with respect to expansion in coke ovens by the simpler test-tube methods; in his first method 80 grains of fine coal were coked in a cylinder heated from the bottom, so that the zone of fusion (plastic layer) advanced from the bottom to the top. The scale of test was too small; it has been modified by other investigators, but without significant improvement in practical application of the results. Somewhat later Koppers and Jendne 5/ experimented with a small-scale coke even, one wall of which was movable, in which the layer-coking in a coke oven could be simulated closely. This oven was heated from both sides. Their results with this oven showed a peak in the time-pressure curves near the end of the coking, period when the two plastic layers, advancing from opposite walls, meet. They also found that although the smaller oven was heated from one side only and did not show the Pressure peak characteristic of two-sided heating, it still gave results entirely too high. Russell built an oven similar to the movable-wall oven of Koppers and Jenkner and compared results obtained in it on Beckley expanding coal with these obtained on the some coal in the Altieri 7/ small-scale apparatus. Both tests were conducted at the same constant pressure, but heating was from two sides in Russell's oven and from one side in the Altieri tester. Russell found that the two types of test gave comparable results under constant pressure conditions even though the heating procedures were quite different. He showed later, however, that a "borderline" coal 8/ that contracted in the Altieri tester at constant pressure developed a peak pressure of 4 pounds per square inch in the movable-wall oven heated from both sides at constant volume. He concluded from this that testing at constant volume gave results more accurately indicative of dangerous expansion tendencies than those at constant pressure. He also found that heating from both sides in this oven gave higher pressure than heating from one side only.

May 1, 1942

By Arno C. Fieldner

This is the fifth of a series of annual reports4/ of technologic investigations conducted by the Bureau of Mines on the occurrence, properties, mining, preparation, and uses of coal. The research of the Bureau is carefully coordinated with the requirements of the producing and consuming industries, with a view to conservation of resources of coal in mining and use, and conservation of the health and lives of workmen employed in these industries. Such coordination is facilitated by the wide range of specialization of the several groups on engaged in studies concerning coal. Here are reported correlated studies ranging from paleobotanic analysis of the formation of coal as it occurred some millions of years ago to the effect of mechanical methods of mining on present-day employment in mines. As this is a summary of the current work of the Bureau of Mines, so the Bureau likewise has provided a condensed review of the outstanding current work of others on research and technology of coal 5/.

Jan 1, 1940

By R. E. Collom

The commercial development of petroleum and natural gas fields has reached its present status within 60 years and is still considered by some operators to be "100 per cent wildcatting." 1 A tendency to drill for gusher production, the production that yields big returns in spite of any mechanical defects in drilling methods, has frequently caused drillers to pass by oil-bearing strata of comparatively small yield and actually to overlook rich oil zones in proved fields; in addition, whole fields have been ruined by water because development methods were never carried beyond a hole-in-the-ground stage.2 Unfortunately, the petroleum industry has no mine dumps or tail. ing piles as at metal mines to yield fortunes through later and bette!' methods of treatment. The wasted oil and gas are gone, as are the time, money, and effort wasted in ill-advised or haphazard drilling. Probably as production costs increase less oil will be wasted, but the need to develop and produce from sands of low yield will become more urgent with the increase in consumption of oil and the decrease in supply. Hundreds of wells are producing steadily as the result of months and perhaps years of careful prospecting and of tests during drilling. The Bureau of Mines has studied the testing and drilling methods used at such wells, and presents in this paper a criticism of these methods and suggestions on future work. The term pr08- pecting here means correct identification and measurement of strata as they are exposed by the drill. The term testing means the determination of the kind and amount of fluid stored within the pores or crevices of any stratum exposed in the hole.

Jan 1, 1922

I. Domestic Production and Use: In 1981, 13 companies operated 32 primary aluminum reduction plants, with 3 firms accounting for 58% of production, Washington, Oregon, and Montana accounted for 32% of the total production; Texas, Louisiana, and Arkansas 16%; Tennessee, Alabama, South Carolina, and North Carolina 17%; other central and eastern States 35%. Based on published producer prices output of primary metal in 1981 was valued at over $7.5 billion. Aluminum consumption by 25,300 firms was centered in the East Central United States. Packaging accounted for an estimated 30% of domestic consumption in 1981, building 21%, transportation 18%, electrical la%, consumer durables 8%, and other uses 13%

Jan 1, 1982

By E. D. Gardner

This paper discusses small-scale lade gold mining and milling. It is abstracted from a bulletin being prepared by the United States Bureau of Mines entitled "Equipping, Developing, and Operating Small Gold Mines." Gold is widely distributed in the mountainous regions of the United States; relatively few deposits, however, can be profitably worked on a large scale. Because of the high intrinsic value of gold, ores containing this metal may be very rich; hence it is possible to mine profitably smaller bodies of gold ore than of the more common metals.

Jan 1, 1934

By Alfred Weiss

These volumes report on the study initiated by the U. S. Bureau of Mines to develop and apply a methodology to quantitatively assess the probability and potential benefits of technological innovation over the next twenty-five years. The potential was recognized for new technology to solve copper industry problems in the United States. Objectives of the study were to: (1) Develop a methodology to obtain the opinions of mineral experts about future events -their likelihood of occurrence, and, conditional on occurrence, when and to what extent they are likely to occur; (2) Identify, select, and describe potential technological innovations which would have significant impact on copper production; (3) Implement the methodology and obtain the opinions of the mineral experts regarding selected copper technologies; and (4) Analyze the expected future benefits of successful technological innovations :n the copper industry. Although individual technologies are continuously examined throughout the copper 'community', this study is the first known comprehensive forecast of future copper technology. This study is also believed to be unique 1n that it represents the consensus opinion of over sixty expert copper technologists on the expected use of innovative technology in the industry over the next 25 years. The report is contained in three volumes.

Jan 1, 1983

By C. B. Manula

This report is mainly concerned with the modification and development of a users manual for the Open-Pit Materials Handling Simulator (OPMHS) developed at Penn State. Model Modifications included the introduction of a free-format input, the application of a Weibull random generator, facilities to stochastically simulate shovel-dragline operations, and routines to increase the flexibility in making truck assignments. At the same time, core storage requirements and execution times were minimized and all P.S.U. conventions were removed to allow operation on other computing systems.

Jan 1, 1976

Five watersheds, ranging in size from 29 to 49 acres, were selected in East-Central Ohio to investigate the hydrologic and water quality conditions occurring before, during, and after surface mining. Four of the watersheds will undergo surface mining, involving either the Number 6, 9, 11, or 8 coal seams, and one watershed having an outcrop of the Number 6 coal will be operated as a control watershed. To determine the premining hydrologic and water quality conditions (Phase 1), physical information was obtained for each watershed and instrumentation was installed for obtaining hydrologic data and water quality samples. In addition to topographic maps, soils and vegetation maps were prepared. Stratigraphic columns were developed from geologic cores; networks of observation wells and of soil moisture access tubes were installed; and weather stations were established to measure temperature, humidity, wind and solar radiation, and to collect precipi¬tation samples. Field data were collected over a 10-month period for one watershed and for about 8 months on another watershed before surface mining began. The other watersheds continued in the premining data phase. These data were for precipitation, temperature, relative humidity, wind speed, solar radiation, snow and frozen soil, soil moisture, infiltration (rainfall simulator), spring discharge, runoff from watersheds, and ground-water levels. Also, samples of runoff and ground water were obtained for chemical analyses and additional samples of runoff were acquired for suspended sediment load determinations. Over the study period, precipitation was not very representative of the long term averages, but data are available from the control watershed for a representative 7 year period which should prove invaluable in modeling the hydrology of the project watersheds for the premined conditions. Spring discharges (before mining) from the upper aquifer of two of the watersheds averaged only 508 and 652 gallons daily. The proportion of precipitation occurring as surface runoff from the large watersheds ranged from 8 to 36 percent and the peak discharges from 5.86 to 81.95 cfs. Base-flow and runoff water samples from four of the watersheds (unmined conditions) were collected and analyzed quantitatively for 39 water quality parameters. Monthly precipitation samples sediment fractions of the base flow and runoff were analyzed for 22 and 17 parameters, respectively. The average concentrations of the water quality parameters for the watersheds (unmined), except for suspended solids, were as low or lower than the EPA recommended maximum allowable concentrations in drinking water. Several parameters in precipitation equaled or exceeded the levels of corresponding parameters in runoff water. The average concentration of suspended solids in storm runoff ranged from 118 to 1110 mg/l, and for base flow the range was from 44 to 247 mg/l; the higher concentrations were associated with the watersheds exhibiting the greatest disturbance. Iron ranged from an average of less than 3 µg/1 to 228 µg/1. Manganese ranged from less than 41 µg/1 to 334 µg/I. Ground-water systems (unmined condition) are described for the five project watersheds. Each watershed was found to have two major perched aquifers within the top 250 feet. Generally, these perched aquifers involve local flow systems, though flow across watershed boundaries in some areas. Recharge is mostly from local precipitation and discharge is mostly as spring flow, base flow, evapotranspiration, and leakage through the underlying confining bed. Shallow ground water was commonly of the calcium bicarbonate type. Although dissolved-solids concentration was generally 200 to 600 mg/1, brackish or salty ground water was present in several areas. A composite hydrologic model for the project watersheds will consist of separate ground-water, unsaturated flow, overland flow, and evapotranspiration component models. The ground-water model (a modified quasi-three--dimensional U. S. Geological Survey model) operates on a grid network and the newly formulated unsaturated flow model was divided into overlying prismatic elements for numerical solutions. The unsaturated flow model includes provision for incorporating the evapotranspiration model. An available distributed kinemetic overland flow model was utilized. An analyses was made of one of the costs of reclaiming coal mines; the legal and administrative costs of complying with legislation. Such costs borne by coal companies under the Ohio law are thought to be a surrogate of these costs under the new Federal law. Regression analyses were used to relate the legal and administrative costs to acres in the permit and the tonnage of coal produced.

Jan 1, 1978

By J. E. Hipp

Three electrostatic field sensing proximity warning devices were tested using full-scale cranes and power line systems, a scaled model facility, environmental testing facilities, and theoretical/numerical analysis. The design objective of each device is to assist in safe crane operation near overhead power lines. Several design deficiencies (varying from device to device) were observed, including inadequate overlap in sensitivity ranges, utilization of vacuum tubes and electro-mechanical parts, temperature sensitivity and inaudible alarms. In addition, the testing showed major device limitations including sensitivity to boom orientations and length, polarization dependent responses, and unreliable operation in the presence of multiple power line circuits. The multiple power line circuit problem is intrinsic to electrostatic sensing devices. The remaining deficiencies and limitations are correctable within a state-of-the-art design. This investigation is not intended to evaluate the safety aspects or policy of utilizing proximity warning devices. Rather, the purpose is to determine the performance characteristics of such devices in relation to the criteria specified in proposed MSHA regulation 77.805-4 (i. e., the devices must alarm at a distance of 10 feet from the power line).

Jan 1, 1980