Thesis (M.Sc.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 117-125.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2002. / Restricted until October 2003. Includes bibliographical references.

The aim of this thesis was to study the effect of the treated oil refinery effluents of Bahrain Petroleum Company ( BAPCO ) on the marine environment. The study has been carried out in seven chapters, the first de~ling with general introduction about the physical environment of the Arabian Gulf and its oil industry in addition to marine pollution and fishery in Bahrain. The second chapter was aimed at studying the quality of water at different areas in Bahrain to compare it with the quality of water at an area adjacent to the refinery outfalls. The third chapter deals with the impact of the refinery on the marine environment. The research approach adopted was ecological and observational I involving water and sediment analysis. The fourth chapter was aimed at studying the effects of the refinery effluents on the fish through toxicity tests and estimation of trace metals and hydrocarbons in the fish tissues. The studies were conducted with several effluents from the main and side streams of the refinery, outlets of the induced air flotation unit and Sitra separator. The fifth chapter was aimed at studying the effect of Sitra oil storage tanks treated effluent on the intertidal fauna of the adjacent area. The sixth chapter deals with a general discussion on the whole studies. While the seventh chapter deals with sions and recommendations. From the study conducted , it could be said that in general the water quality of the western and northern regions of Bahrain is better than the water quality of the eastern region. The east has in general higher pH, higher ammonia, higher nitrite, lower nitrate, and higher phosphate levels than the other regions. The higher concentrations of all these substances reflects the urbanisation and industrialisation of this part of Bahrain and the consequent discharges of waste material. The fish, safee, were tested with different concentrations of the refinery main stream effluent using both short and long term exposures. The same experiment was set up using effluents from the side stream, the I.A.F. discharge of the refinery and Sitra separator outlet. The results indicated a greater toxicity of pollutants in the I.A.F. and Sitar separator effluents than in the main and the side stream effluents. The lethal concentration of I.A.F. and Sitra separator effluents which brought death to fifty percent of the test population of fish (safee) within 96 hours was approximately twenty percent. Fish from the experimental media showed a higner concentration of heavy metals. The study of the effect of Sitra oil storage tanks treated effluent on the intertidal fauna of the adjacent area revealed that no fauna was found at stations located just outside the effluent outlet. The sediment of these stations was black, slimy, heavily oiled with a bad smell and contains dead shells and turrets. Away from the effluent, a diverse fauna was found. It is concluded that the BAPCO refinery has a measurable impact on the marine environment of the east coast of Bahrain, and recommenqations are made tor the development of future policies with regard to Bahraini coastal waters.

No description available.

A polyphasic approach was used to examine the impact of contamination on soil microbial community structure. Two systems were examined using a combined biochemical and molecular biological approach. Petroleum hydrocarbon contaminated soils from two Northern Canadian sites, representing long-term contamination, were examined using Biolog GN plates and PCR-denaturing gradient gel electrophoresis (DGGE) analysis of total community 16S rDNA. Results obtained using both methods demonstrated a positive correlation between samples that was based on the geographical origin of the samples, not on contamination level. In the second system, non-contaminated soil was contaminated with the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to monitor the effect of short- to medium-term contamination. Changes in the soil microbial community were examined using PCR-DGGE of total community 16S rDNA combined with RDX mineralization and chemical analysis of intermediates. The non-contaminated loam soil had an inherent RDX degradative capability and contamination of soil columns with 1000 mg RDX/kg soil did not significantly change the 16S rDNA bacterial community profile. The bacterial diversity remained high as estimated by the number of bands present in the DGGE and by NQ-78704 statistical rarefaction analysis of 16S rDNA clone RFLPs. The same soil, used in 10% soil slurries (w/v), demonstrated two apparently different RDX degradation mechanisms based on mineralization and chemical analysis. The differences were based on aerobic versus anaerobic conditions and the presence/absence of Na3 citrate. PCR-DGGE performed on 16S rDNA from aerobic slurries amended with Na3-citrate detected the stimulation of 3 operational taxonomic units, identified as Stenotrophomonas sp., Sphingomonas sp. and a member of the Alcaligenaceae. The results from the two systems examined (short- to medium-term and long-term contamination) demonstrated the utility of a polyphasic approach in the examina

In 1990, an oil recycling plant situated in Hammarsdale, South Africa, was decommissioned and a decision was taken by management to rehabilitate the site in preparation for resale. The heavily impacted area covered over two hecatares and oil contamination penetrated soil to depths in excess of three metres, making excavation and removal of the soil very expensive. The options for remediation of the site were limited. No facility for incineration of contaminated soil exists in South Africa, and landfilling was not permitted. The emphasis in developing a remediation strategy, therefore, focussed upon the possibility of in situ remediation with minimal excavation of soil. This study, the first of its kind in South Africa, was subsequently initiated to assess the feasibility of this approach, the results of which would underpin a full-scale cleanup programme. The development of such a strategy involved four key stages of work : (1) a comprehensive site investigation to evaluate and fully understand the particular problems at the site; (2) treatability studies to determine the potential for biological treatment of the contaminated soil and the optimisation of such treatments, particularly in terms of time and cost; (3) the testing of some of the more effective treatments on a pilot-scale; and (4) recommendations for full-scale bioremediation of the contaminated site. various conditions unique to South Africa had to be considered at each stage viz. the lack of funds and remediation experience, which created numerous problems and emphasised the requirement for a simple, "low-tech" approach. Site investigations revealed that in situ remediation may be possible due to the high permeability of the sandy soils and low concentrations of heavy metals. Laboratory experiments also showed that a mixed association of indigenous microorganisms was present which, once stimulated by nutrient supplementation at C:N:P, ratios of between 10:1:1 and 20:1:1, was capable of degrading total petroleum hydrocarbons at an average rate of 11% week -1. Further experimentation, aimed at reducing the cost of remediation and improving the soil quality, focussed on the efficacy of oil solubilisers, a soil ameliorant (composted pine-bark), indigenous fungi and higher plants in the remedial process. Three commercial surfactants (Arkopal N-050, N-060 and E2491) and one natural solubiliser (soybean lecithin) were tested for their biotoxicity, solubilisation and biodegradability at various concentrations (0.01 - 1.0%). Formulation E2491 was able to support a microbial population and was selected as the preferred commercial surfactant if soil washing was to be recommended; however, lecithin was considered to be more useful in situ because of its localised solubilising effect, biological origin and nutritional contribution. The use of fungi was of particular interest in addressing the persistent organic compounds, such as the heavy fractions of oil, for which bacterial remediation methods have been slow or ineffective. While it was not possible, however, to demonstrate in the laboratory that the indigenous fungi contributed significantly towards the degradation of the contaminating oil, the basic trends revealed that the fungal component of the indigenous microbial population was readily stimulated by the addition of nutrient supplements. The bulking-up process was also a success and additional exploratory work was proposed in the form of a larger scale composting design. Finally, the potential for using higher plants and 20% (v / v) composted pinebark (in addition to nutrients) to increase the microbial degradation of the contamination was investigated in both greenhouse and field plot studies. Greenhouse investigations employed soybeans which were postulated to have soil quality and cost benefits. However, although the soybeans were found to significantly enhance the remedial process, the complex soil-contaminant- plant interactions gave rise to strange nutritional effects and, in some cases, severe stunting. In contrast, the field studies employed grasses that had previously established on the site and which ultimately demonstrated a better tolerance for the contaminated conditions. Scanning electron microscopy revealed that there were considerable differences between the root tips of soybean plants which had been grown in contaminated soil and those which had been grown in uncontaminated soil. It was concluded that toxicity symptoms, which are readily observed in the root, could be used as an early indicator for determining the suitability of vegetation for remediation purposes. In both instances, despite the differences, the addition of composted pine-bark and nutrients (nitrogen and phosphorus) resulted in total petroleum hydrocarbon reductions of >85%, illustrating the benefits of plant establishment and oxygen availability. The need to link results from laboratory or pilot-scale experiments to achieve reliable predictions of field-scale behaviour was an essential component of this research. The results of the field study provided evidence, similar to that found in the pot trial, of the accelerated disappearance of organic compounds in the rhizosphere. All experiments incorporated parallel measurements of hydrocarbon residues, microbial activity and pH changes in the contaminated soil, the results of which strongly supported the argument that biodegradation was the dominant component of the remediation process. Thus, after consideration of the significant interactions which dominated the study (time-contaminant-nutrient; time-contaminant-pine-bark; and time-contaminant- pine-bark-plant), it was clear that, aside from these limiting factors, little should preclude the in situ bioremediation of the impacted soil. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1996.

Thesis (M. Env. St.)--University of Adelaide, 1984. / Includes bibliographical references (leaves 273-308).

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains vi, 93 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 47-52).

Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr Amy B. Chan Hilton, Florida State University, College of Engineering, Dept. of Civil and Environmental Engineering. Title and description from dissertation home page (viewed June 18, 2004). Includes bibliographical references.

Thesis (Ph.D.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 120-137.