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The role of advanced technologies in the remediation of oil spilled environment was investigated. Oil spill remediation technologies for the clean-up of soil and groundwater contamination from petroleum industry activities have advanced considerably over the past decade. This has been the result of increasing regulatory pressures in many parts of the world, mounting liability exposure, changing public perceptions, and the drive towards enhanced remediation in terms of cost effectiveness, health and environmental concerns, operation and maintenance requirement, applicability and efficiency. This paper examined the state of remedial technologies for petroleum industry applications in ex-situ and in-situ conditions, and used an effective score drawn from research to develop a decision matrix for selection evaluation. Ex-situ technologies involve excavation and treatment of contaminated soil. These include methods such as pyrolysis, solvent extraction, oxidation/reduction, and bioremediation, designed to remediate the soil to acceptable standards. In-situ technologies involve alteration of sub-surface flow, pressure, chemical or biological regimes to achieve containment, redirection, removal or destruction of contaminants. They include soil vapour extraction, bioventing, bio-sparging, and the use of horizontal wells and semi-passive barrier systems. A decision matrix was then developed using Microsoft Excel to aid decision making. This was developed using an effective research score allocated to each evaluation criterion and weighted using the ratio of this effective score to the total score by hundred percent. The optimal remedial approach depends on the highest ranked score as computed and documented in the MS-excel spreadsheet. From the analyses shown in the ex-situ decision matrix, advanced bioremediation was found to the best placed technique with a weighted score of 7.048 and the highest rank of 1, while wet oxidation was found to be the least impressive technique with a weighted score of 2.022. [ABSTRACT FROM AUTHOR]

Oil spillage accidents can cause severe short-term effects to marine organisms and may lead to devastating long-term impact to marine environments. This study determined the influence of water accommodated fractions (WAFs) of diesel oil, chemically enhanced WAFs (CEWAFs) of diesel oil and oil dispersant (IPAC-OCD) to the toxicity of green algae, Tetraselmis chuii, and marine diatom, Chaetocheros calcitrans. Both the phytoplankton species were exposed to different concentrations of WAFs, CEWAFs and dispersant (0%, 5%, 10%, 20%, 40%, 80%). All of the toxicants significantly reduced the growth of phytoplankton, however, the level of response varied by solution and species. The dispersant has the highest impact among all the chemicals studied. The dispersant is very highly toxic to C. calcitrans, but still practically non-toxic to T. chuii. Even though, WAFs have higher impact to T. chuii than C. calcitrans, the chemicals are practically non-toxic to both phytoplankton species and, moreover, in short-term exposure, low concentration of WAFs may stimulate the growth of C. calcitrans. However, the mixture of diesel oil WAFs and dispersant cause synergistic toxicity to C. calcitrans that increases the WAFs toxicity. This finding implies that the dispersant application to mitigate the oil spills may negatively impact the marine phytoplankton. [ABSTRACT FROM AUTHOR]