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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A survey of the factors which affect mining of the lower Mississippian coals in Montgomery County, Virginia

Stevens, David Woods January 1959 (has links)
"Factors Which Affect Mining of the Lower Mississippian Coals in Montgomery County, Virginia" ie a study ot the Merrimac and Langhorne seams of the Price formation in Montgomery County, Virginia. The main reference used in the review of literature was Bulletin XXV of the Virginia Geolog1cal Survey by Marius R. Campbell. The review of literature discusses geologic formations and structure and the coal as seen in various prospect and mine openinga by Campbell. The author visited mines during the field investigation and analyzed samples of coal collected at the mines. He discusses past mining operations in Montgomery County and has traced all available mine maps of past mining operations. These are filed as part of the thesis. Core drillings were also investigated by the author and reported depths of the coal in the Blacksburg syncline ere entered in Table III and Figure I. An investigation was also made into mining methods used in Montgomery County including a discussion of explosive gases encountered in mining the Merrimac seam. The author discusses the results of the investigation in the conclusions. Be ia convinced the coals of the Valley fields, although of poor quality, will becane increasingly valuable as anthracite deposit in Pennsylvania and bituminous deposits in Southern West Virginia and southwest Virginia are depleted. / Master of Science
2

Economic analysis of the Virginia steam coal market

Smith, Martin L. January 1988 (has links)
In recent years the Central Appalachian coal industry has suffered from a number of changes in the structure of the coal market. Foremost among these changes have been the collapse of the domestic steel industry and the passage of the Staggers Act. In the past high quality central Appalachian coal was sold mainly as premium coking coal. This market failed, and continues to shrink. Regional coal producers are now looking to the rising demand for steam coal in a nation which is turning away from oil and nuclear power generation. With the possible passage of the Clean Air Act, low sulfur central Appalachian coal may have a promising future, but only if its production can reach this new market. Prior to 1980, regulated rail tariffs gave coal producers access to most consumers, while independent railroads competed for freight. Railroad deregulation greatly improved the position of the railroads, but weakened that of regional coal producers. Central Appalachia and the southern coastal states were left with only two railroads, CSX and NS. These railroads now set their own rates and secretly negotiate contracts with shippers. Due to the configuration of ownership of these tracks, the vast majority of mines and utility plants were left with access to only one carrier. In this situation rail transportation has become the primary concern. Mines unable to originate shipments on the same railroad which is serving the utility plant find themselves locked out of that market unless their mine price is sufficiently low enough to compensate for the increased rail rate. Most of the coal burning plants in Virginia are located on CSX, while the vast majority of southwest Virginia's coal production is served by NS. With a higher mining cost than in eastern Kentucky and southern West Virginia, Virginia producers are having great difficulty in competing in the state's steam coal market. This dissertation is the first effort to quantitatively specify the regional steam coal market. This is done by identifying sources of data which are subsequently used to generate short term forecasts of mine price. These forecasts are used in the cost vector of a Virginia coal Purchasing model which is solved to determine the optimal pattern of coal purchases for Virginia utilities. The structure of the model is based on a detailed market analysis which accounts for the influence of rail rates. / Ph. D.
3

Investigation of coal bumps in the Pocahontas No. 3 seam, Buchanan County, Virginia

Lessley, John C. January 1983 (has links)
Attempts to recover reserves of coal situated within barrier pillars in the Beatrice Mine using the room and pillar method have thus far been largely frustrated due to magnitude, in or near the working places shortly after commencement of retreat mining in a given area. Since pillar mining offers the opportunity for achieving relatively high production at a low cost per ton the development of methods for the detection and distressing of areas of high bump probability in advance of mining would significantly improve the competitive position of the deep mines operating in the Pocahontas No. 3 seam in Buchanan County, Virginia. Unstable ground movements occurring within a panel of pillars removed using continuous mining equipment were detected using the microseismic monitoring system developed by the U. S. Bureau of Mines. Areas of high stress occurring within the panel were detected by a series of convergence points installed by the mine operator and by small diameter auger holes drilled into individual pillars. The highest levels of seismic activity were recorded during the mining of pillars which, though themselves suffering convergence to some extent, were situated inby areas in which greater amounts of closure had occurred. The presence of anomalous geologic structures in the roof strata outby, as well as the presence of pillars of irregular geometry, in close proximity to areas of high seismic occurrence was also noted. Of the pillars probed using auger drilling it was determined, using criteria developed in Poland for evaluation of bump prone pillars, that two pillars in the next panel to be mined presented an extreme hazard, while several others were of intermediate hazard potential. The practice of injecting water into pillars through holes drilled well in advance of mining was found to be largely ineffective, though injection carried out immediately following drilling of the hole in a highly stressed pillar did induce rapid convergence for a period of approximately two weeks. / M. S.
4

Physical, chemical and mineralogical properties of mine spoil derived from the Wise Formation, Buchanan County, Virginia

Howard, Jeffrey Lynn January 1979 (has links)
Physical disintegration of the rocks is promoted by the closely spaced blast-hole grid used in the mining operation. Wet-dryfreeze-thaw forces are effective in causing disarticulation of the weakened rocks in 6 months or less. The silty spoils cause excessive dust, are crusted and support ponds. Application of organic amendments promotes infiltration. Some of the spoils contain enough salts to seriously retard growth of non-tolerant plant species. Exchangeable bases are overestimated, but the salts are a nutrient source. K is low, but adsorption isotherms indicate that, unlike the naturally occurring soils of the locality, there is no serious problem of K-fixation in the spoils. NaHCO₃ gives the most accurate measure of spoil P. A response to fertilization is likely. Adsorption isotherms suggest a problem with P-fixation by the goethite rocks. There was no measurable pedogenic activity in the spoils after two years of weathering other than physical disintegration of rock fragments and weakly developed structure in some spoil surface layers. There was no evidence of leaching of salts during this period. When regrading the spoils on the benches, maintenance of adequate drainage is essential to prevent nutrient depletion, Fe-generated toxicity and acidity and toxic accumulations of salts. A mixture of 70% sandstone, 20% siltstone and 10% shale should yield a well-drained sandy loam spoil upon weathering. The ferruginous and silty rocks should be regraded well below the surface. / Master of Science
5

Longwall mining, subsidence, and protection of water resources in Virginia

Roth, Richard A. January 1989 (has links)
In the coalfields of Southwest Virginia, Iongwall technology accounts for an increasing proportion of underground coal mine production. lt is a highly productive, capital intensive method that provides a degree of mine safety greater than conventional methods. However, subsidence caused by Iongwall mining has been blamed for, among other things, damaging wells, springs, and streams above the mines. Surface landowners whose water supplies are affected by Iongwall mines may negotiate with mining companies for compensation, or they can seek redress in the courts. At the same time, the U.S. Surface Mine Control and Reclamation Act (SMCRA) provides a framework for regulation of the environmental effects of coal mining, including hydrologic effects. The Department of Mines, Minerals, and Energy, Division of Mined Land Reclamation (DMLR) is responsible for implementation of Virginia’s primacy program under SMCRA. This research has assessed the potential of Iongwall mining to damage the groundwater and surface water resources In Southwest Virginia; and examined whether existing laws and regulations, as implemented, provide an adequate and appropriate level of protection to both water property rights and the environment. Methods included review of published and ongoing literature on effects of underground coal mining on hydrologic systems and methods of mitigation; review of mining permits and complaint investigations on file at DMLR; review of court case decisions involving mining effects on groundwater and surface water; review of regulatory documents from other states active in Iongwall mining and the Federal Office of Surface Mining (OSM); and interviews with coal company personnel, DMLR and OSM officials, researchers, and regulatory officials in other states. Review of both DMLR complaint investigations and published reports of numerous hydrologic investigations indicate that longwall mining is likely to alter the hydrologic regime in the vicinity of the mine. The knowledge base for regulation of hydrologic impacts has been inadequate but is being improved in Virginia. Both DMLR and some coal companies recognize the need for more and better data, and are taking steps to develop the requisite data and models. Regulatory personnel in Ohio, Pennsylvania, West Virginia, and Kentucky have expressed recognition of similar data deficiencies in their states. At least one state, Ohio, has dealt with the problem of water rights by enacting legislation that assigns liability for replacing damaged water supplies to the mining companies. West Virginia, through its regulatory program, also requires water replacement. Recommendations are offered that have as their main objective the reduction of uncertainty about the effects of longwall mining and about compensation of surface owners for damage to water supplies. / Master of Urban and Regional Planning / incomplete_metadata

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