Copper from dump, heap, and in situ leaching accounts for about 15% of United States copper production. In situ leaching is the least understood and most difficult to evaluate of these leaching methods. Several types of supergene copper deposits are derived from porphyry copper systems depending on the geologic and climatic factors involved in the formation of a deposit. The geologic and climatic factors involved in the formation of a deposit. The geologic evaluation of a deposit should provide most of the basic information required to access a deposit for in situ leaching. Metallurgical testing can determine the leachability and acid consumption of the ore as well as the need for an oxidizing agent through the use of agitation and column leaching tests. The location of the deposit with respect to the water table determines the type of ground preparation required. Hydraulic fracturing can be used for deposits below the water table and blasting or caving can be used for deposits above the water table. Fluid flow through the deposit depends on the method of application, the permeability of the deposit, and the method of egress from the deposit. The leaching of a copper "oxide" deposit depends on the strength and volume of sulfuric acid which reaches the ore. The leaching of a copper sulfide deposit depends on an oxidant as well as sulfuric acid reaching the ore.

The Virgilina District, which occurs in the Carolina Slate Belt of Virginia and North Carolina, produced over 300,000 tons of copper and significant amounts of silver and gold between 1852 and 1916. A detailed examination of the ore and gangue mineralization from the district reveals that the ores display two stages of hypogene deposition and a significant phase of supergene alteration. Hypogene mineralization, in decreasing order of consists of bornite, chalcocite/djurleite, an ilite, digenite, chalcopyrite, pyrite, magnetite, ilmenite, rutile, hessite, and gold (fineness 850). Supergene mineralization, in decreasing order of abundance is malachite, covellite, cuprite, digenite, hematite, chalcopyrite, chalcocite/ djurleite, azurite, spion kopite, and yarrowite. This represents the first reported occurrence of djurleite, anilite, hessite, spionkopite, and yarrowite in the area. Lamellar intergrowths of anilite and djurleite on their close packed planes, myrmekitic intergrowths of bornite and chalcocite/djurleite, coexisting chalcocite and djurleite, and gradational transitions from an-ilite to digenite were determined to have formed by secondary hypogene reactions that removed iron and sulfur from the bornite and increased the copper: sulfur ratio, which shifted the Cu-S binary phases towards copper and produced the described textures and intergrowths. The nature of the source of ore fluids and the timing of the mineralization are not known precisely. Fragments of wall rock contained within the veins with schistosity at an angle to the regional schistosity constrain the veins to be post-Taconic, and the metals are likely derived in part from the metamorphosed mafic volcanics in the area. / Master of Science

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Organic contamination is associated with inorganic contamination in a plume resulting from acidic mine drainage water in an area of copper mining, Globe, Arizona. The level of dissolved organic carbon (DOC) is low, but is eight times the 0.5 mgC/l background. The source is probably organic reagents used in mineral processing. DOC fractionation using XAD-8 resin sorption chromatography gave a hydrophobic acid fraction (humic substances) of 1.0 mgC/l, and the hydrophobic neutral fraction was also anomalous, being as high as 49% of DOC. The fractionation data matched that for a waste-solution lake, believed to be a source of the aquifer contamination. Loss of DOC is occurring downgradient in the aquifer, based on comparison of DOC/chloride ratios. Loss occurs as the pH increases to over 4 or 5. Sorption onto metal precipitates being formed, particularly of the hydrophilic fraction, may be occurring.

A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, South Africa, in partial fulfilment of the requirements for the award of the of Masters of Arts Degree in Labour and Development, Economic Policy, Globalisation and Labour (Labour Policy and Globalisation). Johannesburg, 2016 / Zambia has been implementing economic liberalisation policies at the advice of the IMF and the World Bank, to reverse years of economic decline that began with the commodity crisis of the 1970s. As a strategy for economic growth, these included, the deregulation of foreign investment, removal of currency controls, trade liberalisation, decontrolling prices, cutting food subsidies, reduction of state control in running the economy and privatization of state run companies. The rapid implementation of these measures by the Zambian government has seen a change in employment trends in the mining industry from permanent employment to casualisation of labour.These measures have resulted into negative social and economicconsequences on the lives of the casualised mine workers such as job insecurity, poor health and safety standards, lack of protection and union representation, poor remuneration, lack of pension,and other forms of exploitation. Despite booms and busts in the copper price, employment levels have been drastically dropping especially among the permanent mine workers as a cost cutting measure. The role of the state in the running of the mines which Zambia has depended on since independence has diminished significantly and the state is increasingly succumbing to the dictates of the mining Trans-National Corporations (TNCs).The study which was conducted among casualised/contract rock ore drillers at Mopani Copper Mines Plc reaffirms arguments by previous researchers that economic liberalisation has not achieved the high expectations that Zambians wished for and that there is need for government and trade unions to protect the welfare and working conditions of these casualised mine workers who have become a new set of underclass. Through in-depth interviews, observations and documentary analysis, this research has brought to light the social and economic experiences of casualised/contract rock ore drillers at Mopani Copper Mines Plc and questions whether Zambian mine workers were better off when the mines were being run by the state than is currently the case under TNCs. / MT2017