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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.
351

Oil pollution management and environmental assessment in the Niger Delta : a case study of operations of Chevron Nigeria LTD in Ugborodo community in Delta State of Nigeria

Eyitsede, Tosan S. N. 09 1900 (has links)
Since the discovery of oil in Nigeria, way back in 1950s, the country has invariably suffered some negative environmental consequences such as oil pollution resulting from gas flaring and oil extraction, loss of mangrove trees, which before now was a source of livelihood for the indigenous people and habitat for the area’s biodiversity. Oil production activities have caused contamination of marine life, and habitat, which in turn have had negative consequences on the health of humans, who consume the sea food. Inadequate attention had been paid by the successive Governments of Nigeria and the oil companies to these environmental problems over the years. In this study, an assessment of the effects of oil and gas exploration and exploitation on the nearby communities in some of Chevron’s operational areas was carried out using the Ugborodo community as a case study. Furthermore, investigations were carried out on the toxicity effects of the Escravos crude oil on aquatic organisms like Tilapia and a terrestrial organism such as the Earthworms (Lumbricus terrestris,). The study established the effect and the impact of crude oil when exposed to such organisms mentioned above. The rate of death of barbus fingerlings of Tilapia and the Earthworm (Lumbricus Terrestris) at different concentrations of crude oil was determined and reported. The community survey undertaken by polling data shows the dwindling of the natural resources of the area due to oil exploration and the survey indicate the impacts on natural resources from pollution by crude oil and the consequences on the affected communities using the Ugborodo community in the Chevron’s Nigeria Limited Operational base as a case study. / Environmental Sciences / M.Sc. (Environmental Management)
352

An investigation into factors increasing contamination risk posed by fuel storage facilities and concomitant methods to mitigate these risks.

Pfotenhauer, Torin. 23 September 2013 (has links)
Light Non-Aqueous Phase Liquids (LNAPLs) are used throughout the world for numerous applications, the most well-known being automotive fuels, such as petrol and diesel. The widespread production, distribution, storage and use of LNAPLs results in the ubiquitous occurrence of spillage to ground (Geller et al, 2000). Considering the hazardous nature of most LNAPLs due to their explosive and toxic characteristics, releases of LNAPLs to ground have well documented human health and ecological consequences. The occurrence of leaking underground and above-ground storage tanks at service stations and consumer installations is a common cause of contamination; and is described in literature for various countries of the world (Dietz et. al., 1986; Moschini et al, 2005; Mulroy and Ou, 1997; Harris, 1989; The Institute of Petroleum, 2002). Little failure data are however available for the South African context. In addition to this, data concerning the location and characteristics of sites storing LNAPLs in South Africa is similarly scarce. The study analysed data from three sources, namely the eThekwini Fire and Emergency Services data, GIS data and data from a local consultancy, in order to determine whether certain factors increased contamination risk posed by these facilities. The results indicated that contamination may be a result of numerous factors, but primarily line and tank failure. The type of installation was also found to have a significant influence on whether a site would be contaminated or not. In addition to the above, the results indicated that certain circumstances increase the severity of loss. The results indicated the need for more investigation to be performed into contamination as a result of LNAPL loss to ground, and the need for protective measures to be implemented for high risk sites where the likelihood and severity of a potential loss is high. Focus should then be centred on the probability of failure of non-ferrous pipework and GRP tanks to ensure adequate protective mechanisms are in place in the event of a failure of this newer infrastructure. In addition, a review of regulatory control of LNAPL storage in South Africa and the eThekwini Municipality, with reference to the international context, indicated the need for a specific department within the local government structure that manages LNAPLs with the objective of reducing contamination incidents. The continued use of underground storage of LNAPLs will always present a risk of failure/contamination due to the unseen nature of the installations and related infrastructure. It is this risk that requires regulatory management. Details of contaminated sites in South Africa should be within the public domain. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2011.
353

Oil pollution management and environmental assessment in the Niger Delta : a case study of operations of Chevron Nigeria LTD in Ugborodo community in Delta State of Nigeria

Eyitsede, Tosan S. N. 09 1900 (has links)
Since the discovery of oil in Nigeria, way back in 1950s, the country has invariably suffered some negative environmental consequences such as oil pollution resulting from gas flaring and oil extraction, loss of mangrove trees, which before now was a source of livelihood for the indigenous people and habitat for the area’s biodiversity. Oil production activities have caused contamination of marine life, and habitat, which in turn have had negative consequences on the health of humans, who consume the sea food. Inadequate attention had been paid by the successive Governments of Nigeria and the oil companies to these environmental problems over the years. In this study, an assessment of the effects of oil and gas exploration and exploitation on the nearby communities in some of Chevron’s operational areas was carried out using the Ugborodo community as a case study. Furthermore, investigations were carried out on the toxicity effects of the Escravos crude oil on aquatic organisms like Tilapia and a terrestrial organism such as the Earthworms (Lumbricus terrestris,). The study established the effect and the impact of crude oil when exposed to such organisms mentioned above. The rate of death of barbus fingerlings of Tilapia and the Earthworm (Lumbricus Terrestris) at different concentrations of crude oil was determined and reported. The community survey undertaken by polling data shows the dwindling of the natural resources of the area due to oil exploration and the survey indicate the impacts on natural resources from pollution by crude oil and the consequences on the affected communities using the Ugborodo community in the Chevron’s Nigeria Limited Operational base as a case study. / Environmental Sciences / M.Sc. (Environmental Management)
354

The fate and distribution of subsurface hydrocarbons released during the 2010 MC252 oil spill in deep offshore waters of the Gulf of Mexico

Spier, Chelsea L. 01 January 2012 (has links)
The explosion of the Deepwater Horizon oil platform on April 20, 2010 resulted in the second largest oil spill in history. In this study, the distribution and chemical composition of hydrocarbons within a 45 km radius of the blowout was investigated. A complete set of hydrocarbon data were acquired from the National Oceanic and Atmospheric Administration (NOAA) and from BP, including data from 16 research missions collected over eight weeks. The distribution of hydrocarbons was found to be more dispersed over a wider area in subsurface waters than previously predicted or reported. Several hydrocarbon plumes were identified including a near-surface plume (0.5 to 50 m), two small mid-depth plume (240 to 290 m and 850 to 880 m), and a large deepwater plume approximately 1,050 to 1,300 m below surface. Water soluble compounds were preferentially extracted from the rising oil in deepwater, and were found at potentially toxic levels both in and outside of areas previously reported to contain the majority of hydrocarbons. Data collected from different research missions were measured for a wide variety of chemical compounds, but not every sample was analyzed for the same chemical compounds. To overcome the challenge of variability in sample data, a non-parametric method of evaluating the percentage of detectable results, was used for all data analysis in addition to evaluation of total sample concentrations. The two analysis techniques yielded similar results. This approach may be useful in other studies in which samples are measured for varying number of compounds and have varying detection limits. The distribution and toxicity of hydrocarbons in sediments between August and October, 2010 was also investigated and was found to be fairly localized.

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