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By David K. Hylbert

This study was designed to investigate roof falls in room-and-pillar drift coal mines and to determine geologic methods for predicting unstable roof conditions. The study area was located in Harlan County, Kentucky and the Bailey Creek (Harlan coal bed) and Highsplint (Darby coal bed) mines were selected for study. Correlations were made laterally between surface outcrops and within the mines using lithologic and trend analysis criteria. Lithologic criteria compared cyclic changes in roof strata. Results indicated that roof falls are associated with zones of weakness within or between five vertical cycles recognized. Abrupt lateral facies changes occur. In the Highsplint mine the roof was classified in four categories or conditions using 98 rib sections for control. Structure contour and isopach maps were used to project axial trends of the sandstone roof. A roof-fall zone was examined using ten NX cores taken from the roof and included lithologic, petrographic and clay mineral studies. At the Bailey Creek mine roof failure was caused by the heading direction being driven subparallel to paleochannel directions. Computer programs were used in trend analysis studies. Cross-bedding, paleo-channel trough axis and sole mark studies indicated a 350 discrepancy between surface and in-mine trough axes at Highsplint. A direct relationship between joint and "slip" frequency and direction with sandstone roll trends was found. Surface joints compared well with drainage Segments, hilt did not correlate with roof falls in areas of mines under overburden in excess of 600 feet.

Jan 1, 1977

Watershed Jll in Jefferson County, Ohio we instrumented in 1977 as one of three watersheds established for the purpose of investigating surface mining and reclamation effects upon local hydrology, sediment discharge, and sediment and water quality. Each watershed was less than 50-acres in size, and was in a different geologic setting within southeastern Ohio. Surface runoff and ground¬water levels were monitored. Samples were taken for sediment determination and chemical analysis prior to mining. Monitoring and sampling continued through the period of watershed disturbance caused by mining and reclamation activities, which began in May 1980 at Watershed Jll. A psuedo-postreclamation period followed the initial cessation of man-machine activity on the watershed. A second reclamation effort occurred in the fall of 1981 and was to be followed by a third in 1982 after observations ceased. A true final postreclamation period was not monitored at this site, because the erosion control practice (terrace diversions) failed after each reclamation. Watershed Jll was a small pasture and wooded watershed with sandstone and shale above the mined coal seam prior to mining. A clay layer under the coal supported a perched saturated zone, termed the top aquifer for convenience. A lower underclay supported a second saturated zone called the middle aquifer. A lower perched aquifer had been dewatered by previous deep mining. After about three years of premine data and about two and one-half years of mining reclamation and psuedo-postreclamation data, the following general observations may be made: 1. The mining-reclamation phase was very short, and the postmining period was characterized by erosion failures and remedial disturbances that kept the watershed condition and size in a state of change. It was impossible to collect sufficient data to confidently characterize the hydrologic-sediment-chemical aspects of the mining period or of a postreclamation period and, most importantly, of the future watershed after its various properties and characteristics have ceased adjusting to its severe disturbance and reconstitution. 2. A seeding of wheat followed by grasses and legumes was not a particularly successful reclamation practice in terms of stabilizing the new soil. Numerous rills and small gullies developed in spite of installed diversions. 3. Storm runoff rates and yields at the watershed outlet increased from the premine, (phase 1) to the mining-reclamation (Phase 2) periods, and remained at or near the Phase 2 level through the postreclamation (Phase 3a) period. 4. The top aquifer changed in physical and chemical character as a result of mining and was becoming reestablished as the project drew to a close; but it is impossible to predict its final configuration or character. 5. Dewatering of the top aquifer resulted in a complete cessation of baseflow because the middle aquifer water table lay below the elevation of the watershed outlet. 6. The top and middle aquifers were merged in one area of the watershed where the upper coal underclay was disturbed. 7. Failure of the diversion terraces and their outlet obscured the effects of the reclamation practice upon sediment concentration and yields. There was little difference in sediment concentrations between Phases 2 and 3a. 8. Drinking water standards were met by surface waters throughout the period of observation except for two samples that exceeded the nitrate-N allowable level of 10 mg/l. 9. In all Phase 3 surface-water samples, iron concentrations were within the limits established by OSM, and manganese concentrations exceeded the regulation level only once. pH fell below the lower regulation level of 6.0 between 10% and 20% of the time. 10. The chemical quality of sediments was generally about the same after reclamation as before mining, with the exception of organic carbon, which decreased.

Jan 1, 1983

During the period 1979 thru 1982, Multi Mineral Corporation conducted a mining I research program at the United States Department of the Interior's Bureau of Mines Oil Shale Mining Environmental Research Facility in the Central Piceance Creek Basin, Rio Blanco County, Colorado. The program consisted of mining, environmental and geotechnical research data and, the results are described in this report.

Jan 1, 1983

By J. A. HUFF, V. V. BAKER

This circular is intended to present in brief form the statutory provisions of Pennsylvania regarding mining operations, in force at the end of the 1931 session of the legislature. lo reference is made to general laws which affect mining only incidentally in common with other subjects, such as the workmens compensation law. The statements have been condensed as far as practicable, and provisions not deemed of general interest, such as matters dealing only with administrative details, have been omitted. This circular obviously is not written with such particularity as to be of great value to the legal profession, but it is hoped that it will be beneficial to the mining industry in giving this information in a relatively compact form. At the end of each paragraph the statute from which it is derived is cited to facilitate reference to the text of the law. It is planned to publish additional circulars from time to time dealing with the mining laws of other States. Any criticisms of the form of publica- tion followed herein, or suggestions aimed at the improvement of future circulars, will be welcomed.

Nov 1, 1932

Jan 1, 1992

By T. M. Russell

"Face mapping is a simple but invaluable means of geological and geotechnical data acquisition whereby intact rock properties, rock mass properties, discontinuity properties, and structural orientation can be assessed. Although traditionally done via direct contact with the mapping face through techniques such as line mapping or window mapping, remote face mapping using various digital techniques has become increasingly popular in recent years. Sishen is a large open pit mining operation requiring a comprehensive geotechnical data-set to evaluate pit wall design and stability with the necessary level of confidence. Geotechnical borehole data, face mapping data, geotechnical laboratory testing data, and implicit structural models provide the main sources of this information. Although a large geotechnical borehole database has always been maintained at the mine, face mapping has in the past been restricted to sporadic and isolated stability assessments. In 2013 the mine acquired a terrestrial laser scanner with the resolution, photographic capabilities, and software required to carry out geotechnical face mapping. A face mapping procedure was set up based on accepted face mapping methods, the data requirements of the mine, and capabilities of the laser scanner system. Mapping data obtained from the scans was integrated into the Acquire geological data management system, a purpose-designed structured query language (SQL) database system used for storing the mine’s geotechnical data. Within the geotechnical design process, having face mapping data available has improved confidence in the properties of the rock mass and structural environment, allowing for better definition of geotechnical design sectors. Overall, the face mapping and geotechnical analysis features of the terrestrial laser scanner in use make it an invaluable geotechnical data capture tool, provided a system is in place to store mapping data in a manner that allows for meaningful rock mass and structural information to be produced. IntroductionFundamental to the geotechnical design process is the acquisition of a reliable and complete geotechnical data-set. Geotechnical data acquisition will typically commence during the early stages of a project and continue well into the operational life of the mine, with the data confidence progressively increasing as the amount of data captured increases. Sishen mine currently bases all open pit geotechnical designs and geotechnical risk assessment on geotechnical borehole data in conjunction with interpreted structural models. Boreholes are logged and the data is captured in an ongoing process. This process forms the initial step in the geotechnical design and risk assessment process whereby the raw data is used to classify the strength properties for each lithology, provide inputs for geotechnical block models, and ultimately provide the inputs for slope design analyses. To date, borehole data has provided the only largescale, organized data-set for input into geotechnical analyses at Sishen. Although borehole data is the best and most comprehensive form of geotechnical data, there are some shortfalls that can be addressed by other data collection methods. These shortfalls are as follows."

Jan 1, 2018

By A. G. Pronk, D. M. Burton

"A regional till sampling program in the Upsalquitch Forks-Tetagouche Lakes area, centred some 70km west of the city of Bathurst, has proven an effective method for gold exploration in the heavily glaciated interior of northern New Brunswick. Prospecting activities within this area over the past three years, have led to the discovery of several gold occurences associated with quartz-carbonate alteration in a variety of intrusive rock types emplaced along major fault zonesQuaternary mapping shows that the glacial history is complex. However, the displacement of material is uniform in distance and direction, and the till is generally thin (0.5 m to 2.0 m) and locally derived, making the interpretation of till geochemical patterns relatively simple for the explorationist. Previous studies have shown the the fin e-grained gold is best detected in the -250 mesh (-0.063 mm) till fraction (clay plus silt) and that the C-horizon is the preferred medium for analyses.Samples were collected on a 2 km grid and analyzed f or Cu, Pb, Zn, Au, Ag, As, Sb, Mn, Fe, Ni, Co, and Cd. Results indicate that concentrations of 10 to 20 ppb Au can effectively delineate areas of anomalous gold in bedrock associated with fault structures, and that a good potential for discoveries exists to the west of the known occurrences, where up to 678 ppb A u has been detected in tills. IntroductionThis paper reports on the result s of surficial geological investigations conducted over the past two field seasons in north-central New Brunswick. The stud y area is located in the Upsalquitch Forks-Tetagouche Lakes map area s (N.T.S. 21 0 19 and 21 0 (10) 70 km west of the city of Bathurst (Fig. I). The area is situated on the margin of the New Brunswick Highlands and has a maximum elevation of 640 m (for a detailed description of the physiography, see Rampton et al. 1984).Historically, exploration in northern New Brunswick has concentrated on base metals within the Cambro-Ordovician Tetagouche Group, resulting in the discovery of man y significant massive sulphide deposits (Brunswick No.6 and No. 12, Heath Steele, Caribou, Armstrong Brook, Orvan Brook, McMaster, Murray Brook, and Restigouche). Auriferous base metal occurrences along the Rocky Brook-Millstream Fault have also been previously investigated."

Jan 1, 1988

By C. L. Elmore

This paper describes a new development in the cyanidation of gold ores, which we expect will result in a major improvement in the way many gold ores are treated. The process has evolved through work at Hazen Research, Inc. for Kamyr, Inc. and in brief, the consists of utilizing oxygen rather than air in the carbon-in-1 each (CIL) process. We refer to this improved process for all ores amenable to cyanide leaching as carbon-in-1each with oxygen or CILO.

Jan 1, 1988

By Robert H. Richards

Jan 1, 1883

By Harry F. Weaver

Rivers in industrial and raining areas frequently are contaminated by material dumped into them causing the water to carry in suspension large amounts of silt, which subsequently is deposited alone; the banks and, ultimately on the agricultural lands if the water is used for irrigation purposes. Two common examples of this practice are the dumping of breaker refuse in the anthracite region of Pennsylvania and the dumping of tailings from the metallurgical mills in various metal-mining districts. Studies in stream pollution and its resultant problems are very important, and surveys are constantly being made by Federal and State agencies, as well as by private companies, to determine the quantity of solids actually being carried by these watercoarses. These studies require accurate sampling of the silt-carrying water to determine the amount of solids within reasonable limits. A device that will obtain reasonably accurate samples of material from silt-bearing streams is described in this circular.

Jan 1, 1943

By M. Murphy

The multibillion dollar cost of cleaning up thousands of environmentally contaminated sites across the country created by decades of inadequate disposal of hazardous waste has led to a search for "deep-pocket" sources of cleanup funds. The resul1:: is the emergence of a growing body of law that could have a profound impact on commercial financing transactions and other investment activities when present or past owners of contaminated property are involved.

Jan 1, 1988

The question, Who won the war?, has been the text for innumerable newspaper, and magazine articles, the answers running from "bread and butter" to "poison gas," in a material sense, and from the "Y. M. C. A." to the "boys in the front lines," humanly speaking. Personally, I think the margin by which success was secured was so narrow that none of the complex, interdependent factors could have been .spared, and that, as Admiral Sampson said after the battle of Santiago: "There is glory, enough for all." But if any one human factor can be said to have been absolutely indispensable, I think all will agree that it was the engineer. The engineer, as a rule, is a modest fellow, so modest in fact and so averse to publicity of any kind that, referring to him as a class, he was hardly occupying the place he should in public estimation before the war. By way of illustration, in the early history of a mine in Bisbee, the chief owner was also the proprietor of a saloon and spent most of his time there. When asked why he did not pay more attention to the mine, lie replied: "Oh! I can hire a boy to look after that; it takes a man to run this bar." Comparisons of the position and pay of engineers with other occupations are sometimes made to show that the engineer is not getting all that he should, considering the time of preparation and the qualifications required. Perhaps at least a part of the cause may be his aloofness from many of the practical affairs of everyday life. Whether he won the war or not, the part played by the engineer has certainly placed him on a sort of pedestal in the public estimation at present and it is very desirable to keep him there and maintain the position he has made for himself.

Jan 9, 1919

To reduce operator exposure to noise from vibrating screens at coal preparation plants. Background Hearing loss is one of the most common occupational illnesses in the United States. In the U.S. mining industry, hearing loss is 2.5 to 3 times greater than what is expected for the average population that is not exposed to occupational noise. Furthermore, studies by the National Institute for Occupational Safety and Health (NIOSH) showed that by age 50, 90% of coal miners have a hearing impairment versus only 10% of the population that is not exposed to occupational noise. A NIOSH cross-sectional survey of coal preparation plants showed that 43.5% of employees were overexposed to noise. The study also found that vibrating screens were one of the top five loudest types of equipment at these plants?as well as the most numerous?making them a key noise source to address.

Nov 1, 2009

By John V. Beall

The forecast of continued growing demand for phosphate, chiefly for fertilizer, has caused a world-wide rush for deposits by a variety of companies many of which have never before mined phosphate rock. The newcomers are diversifying into this growth industry on the strength of certain capabilities. Among these are the availability of investment capital, mining or processing know-how and marketing experience. Product tie-ins have motivated some into the search. Companies with excess sulfuric acid or potential for making it are in this category. This acid is the most commonly used for dissolving phosphate rock to make phosphoric acid. Base metal smelting companies are prime candidates in this field with by-product acid from roasting processes. Producers of "sweet" natural gas, such as those in Louisiana and Texas, have a potential for recovering low cost hydrogen from excess gas production for the manufacture of ammonia, the main source of nitrogen for fertilizer. "Sour" gas producers, such as those in the Canadian fields, are making sulfuric acid that is combined with western U.S. phosphate to make fertilizer materials. The presence of one or two steel companies in the look-see for phosphate deposits is based on by-product ammonia from coke-oven gas.

Jan 10, 1966

By AIME AIME

RECENT experiments in reflected sunlight photography in mine shaft's' and. slopes in the McAlester, Oklahoma, coal-mining district have been so satisfactory as to indicate that such a method has definite scientific value. The entrances to abandoned deep shafts and slopes on Choctaw and Chickasaw Indian coal lands in Oklahoma are being filled or bulk-headed by the U. S. Geological Survey under Public Works Project F. P. 63-C&C. Inasmuch as these mines may be reopened at some future time when there is a demand for coal, H. I. Smith, Chief of the Mining Division, suggested that photographs of deep shafts would be of value. Such photographs would show timber details and the general condition of the walls. Photographic records of the exact status of shafts when filled will facilitate operations in reopening.

Jan 1, 1936

By John V. Beall

When a mine has ore averaging 5% lead, 7% zinc, 0.60% copper, 1/4 oz gold, and 6 oz of silver, adequate reserves, power and water, easy access to market, and is situated in beautiful natural surroundings with the advantages of a big city within a few hours drive, there is little left to be desired. Such a mine is the Mayflower mine of the New Park Mining Co. situated 30 miles from Salt Lake City in the Wasatch Mountains near Keetley, Utah.

Jan 1, 1949

By T. D. Maki

FMC Gold's Paradise Peak Mine, located 13 km (8 miles) south of Gabbs, Nevada, became operational in April of 1986. Shortly thereafter heap leach testwork began on sub mill grade ore. Presently, testwork continues in combination with production size heaps that account for approximately 6% of total gold production at Paradise Peak.

Jan 1, 1989

By AIME

Lewis E. Young, who will formally assume his duties as President of the AIME at the Annual Meeting in San Francisco in February 1949, was born in Topeka, Kansas, Oct. 1, 1878. Dr. Young received his engineering education at the Pennsylvania State College, where he received the degree of B.S. in Mining Engineering in 1900. In 1904 he received his E.M. degree from Iowa State College, and in 1915 a Ph.D. from the University of Illinois. In 1947, the University of Missouri conferred on Dr. Young honoris causa the degree of Doctor of Engineering. His active career began in the educational field as instructor at Iowa State College, and following that, as professor of mining at the Colorado School of Mines, 1903-1907. While he was at Golden he launched hi: career as consulting mining engineer for various Western companies. Leaving the Colorado School of Mines, Dr. Young returned to Missouri, serving the University of Missouri as director of the School of Mines and Metallurgy at Rolla, 1907-1914. Leaving Missouri he went to the University of Illinois as assistant professor of business organization, 1915-1918, during which period he wrote exhaustive treatises on mine subsidence and mine taxation, which won for him the degree of Ph.D. before mentioned.

Jan 1, 1949

William Metcalf, Pittsburg, Pa. (communication to the Secretary*): I am greatly pleased that some one has at last reached what I have long regarded as the only rational explanation yet given of the reasons why steel hardens. Mr. Field claims originality; and doubtless he is entitled to it, but not to priority, mhich must be granted to Prof. John W. Langley.' The difference between them is that Langley says " Tension, probably molecular," and Field says " Tension, probably atomic "; in either case the vital thing after solution is tension. Mr. Field's argument carries with it the idea of increase of density with hardness; if he mill study the facts farther he will observe that the case is just the reverse; that is, the greater the hardness the less the specific gravity; it was just this fact that led Langley to his conclusion, in mhich I have always concurred. Field agrees with Langley that the first requisite for perfect hardening is complete solution of the carbon, not combination; and all of the facts agree with this conclusion. The fact that increase of hardness causes reduction of density was first brought to my notice some 40 years ago, when Major William Wade was testing Jones & Laughlin's cold-rolled iron, and I mas his assistant. We found the well-known increase of tenacity, compressive strength, torsional resistance, and hardness. Specific-gravity tests showed that the cold-rolled iron was less dense than the hot-rolled bars. Major Wade was so surprised at this result that he gave me a lot of samples to weigh, saying that he was not satisfied with

Jan 1, 1904

It is always difficult to sum up an open forum adequately and instantaneously, so, with the privilege of hindsight, and also with some time to reflect, I am exercising the Chairman's prerogative to put together my view of the overall conclusions. Hopefully, these may provide a focus for each Institute to formulate its own programme with respect to mineral industry education. First, in answer to the question, "Should there be Schools of Mines?", there was a very clear 'yes'. However, I reiterate what I said in the introduction to this forum, specific professional education for the mineral industry exists only because the mineral industry sees a need and wants it. If the mineral industry should decide that it does not need professionals with specific mineral industry training, then such training will cease to exist. As alluded by Dr Hackett, if such training ceases to exist, one must then question the need for Institutes of Mining and Metallurgy. Now, there's some food for thought! Specialist schools of mines (metallurgy and geology) can only exist in an environment of genuine interaction with, and support by, industry. For their part, schools of mines, used here in a generic sense, require leadership that is strong but responsive to industry needs. It is the leader that puts his stamp on a school, and, to a large extent, determines whether that school is 'good' or only 'mediocre'.

Jan 1, 1986