When mining companies extract minerals from the earth, they leave huge deposits of soil and ore next to the mining site. These deposits are commonly known as tailings. In most instances, tailings contain a considerable amount of valuable mineral resources which cannot be exploited because of a lack of appropriate equipment, or as a result of economic non-viability. However, many mining companies choose to keep and maintain these tailings, in the hope that such minerals can later be exploited when time or technology allows for this. Under common-law the owner of a property is considered to also own any minerals contained on the property, in terms of the principle of cuius est solum. In South African law, however, a practice evolved whereby owners of minerals separated rights to minerals from the surface rights on the property. This created a mining right which was independent from the land and could be transferred to third parties, often in return for compensation. Under the Minerals Act of 1991 the owner of a mining right over a property (be that the owner of the property or a third-party mining right holder) also held the mining right to tailings which were created as a result of mining activities under the right. Thus, if a mining company performed mining activities on a property, the company was also free to exploit the tailings which were left next to its mine, regardless of whether the dump had remained there for a long period of time. Owing to South Africa's long history of mining, some tailings are over a century old and resemble small mountains rather than mining deposits. The Mineral and Petroleum Resources Development Act of 2002 changed the entire mineral legislative regime in South Africa. Whereas owners of land were previously free to separate and sell their rights to minerals to anyone they wished, the MPRDA placed the country‟s mineral and petroleum resources under the state's "custodianship." Where the law talks about custodianship, however, it supposedly refers only to minerals that have not yet been extracted from the earth. It is well established in South African law that, once a mineral is extracted, it becomes the movable property of the person who extracted it – in other words, that of the mining company. Does this mean that minerals in tailings also fall under the state's custodianship? The Free State High Court did not think so. In the case of De Beers v Ataqua it held that, in terms of the common law principles of acquisition by way of attachment, tailings are clearly movable property and therefore belong to the mining company who created them. For the MPRDA to hold otherwise would amount to expropriation. The state did not wish for some mining activities to be regulated by a different set of legislation, so it amended the MPRDA to try and define "residue deposits" (the name by which the MPRDA calls tailings) more clearly. However, due to the legislature's unfortunate choice of wording, tailings created before the enactment of the MPRDA are still, strictly speaking, not regulated by that Act. So the legislature proposed another amendment to the Act, this time making sure that any historical mine dump created at any point in South Africa's history are placed under the Act's regime. The subject matter of this study is whether the above amendments to the MPRDA could be considered to be expropriation. For background purposes, a brief overview of the Ataqua decision as well as the subsequent amendments to the MPRDA will be given. Then the history of mining legislation and the development of a separate mining right will be summarised. The reason for this summary is to establish whether, in terms of constitutional litigation, a clear right has been established for purposes of protection under section 25 of the Constitution. The last phase of the study will look at the particular characteristics of expropriation and ask the question whether acquisition of a right by the state is always a fundamental requirement for expropriation to take place. It is submitted that the destruction of an entire class of property by way of legislation, amounts to so-called "institutional expropriation," which is subject to compensation in terms of section 25. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2015

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

The extent of weathering incongruency during soil formation from rock controls local carbon and nutrient cycling in ecosystems, as well as the evolution of hydrologic flow paths. Prior studies of basalt weathering, including those that have quantified the dynamics of well-mixed, bench-scale laboratory reactors or characterized the structure and integrated response of field systems, indicate a strong influence of system scale on weathering rate and trajectory. For example, integrated catchment response tends to produce lower weathering rates than do well mixed reactors, but the mechanisms underlying these disparities remain unclear. Here we present pore water geochemistry and physical sensor data gathered during two controlled rainfall-runoff events on a large-scale convergent model hillslope mantled with 1 m uniform depth of granular basaltic porous media. The dense sampler and sensor array (1488 samplers and sensors embedded in 330 m(3) of basalt) showed that rainfall-induced dissolution of basaltic glass produced supersaturation of pore waters with respect to multiple secondary solids including allophane, gibbsite, ferrihydrite, birnessite and calcite. The spatial distribution of saturation state was heterogeneous, suggesting an accumulation of solutes leading to precipitation of secondary solids along hydrologic flow paths. Rapid dissolution of primary silicates was widespread throughout the entire hillslope, irrespective of up-gradient flowpath length. However, coherent spatial variations in solution chemistry and saturation indices were observed in depth profiles and between distinct topographic regions of the hillslope. Colloids (110-2000 nm) enriched in iron (Fe), aluminum (Al), and phosphorus (P) were mobile in soil pore waters.

Bisphosphonates (BPs) are stable analogues of pyrophosphate widely used for the treatment of bone diseases characterised by increased bone resorption. Studies over the years have shown that the pharmacological potencies of BPs are dependent both on their binding affinities for bone mineral and on their inhibitory actions on osteoclasts. In addition, potential effects on other cell types present locally in the environment of skeletal tissues have been reported. The present study systematically evaluated the relative mineral-binding affinities of individual BPs of clinically relevance in mixtures of these compounds and the changes with elution pH by using column chromatography with ceramic hydroxyapatite and fluoroapatite combined with mass spectrometric identification and quantitation of the individual BPs. The results indicate that pH has a profound effect on the ionisation of the phosphonate and R2 functional groups, with BPs having greater affinities at lower pH as shown by increased retention times. Moreover, two other approaches, namely using Langmuir adsorption isotherms and competition assays based on fluorescent BP, have been developed to assess the mineral-binding capacities and dissociation constants of BPs. These results suggest that there are substantial differences among BPs in their binding to hydroxyapatite. From the cellular aspect of my study, I present evidence for the anti-apoptotic effects of BPs in osteocytes and osteoblasts. However, the study of prosurvival signalling pathways involved in these cells needs to be optimised. The work described in this thesis provides novel insights into the physiological and biological mechanisms of BP action. My project has provided a better knowledge of the physicochemical properties of BPs, which are highly relevant to their differential distributions within bone, their biological potencies, and their durations of action. Additionally, the cell culture studies may provide new information on the cellular effects of BPs on osteocytes and osteoblasts.