W11 PM Advances in Biorestoration Strategies for Contaminated Sediments
Wednesday, 16 November 2005: 1:50 PM - 5:30 PM in 343-344

(MUR-1118-278542) Bioremediation of weathered oil from the 1991 Gulf War.

Murphy, T¹, Shaw, R², Guo, J¹, Parr, T¹, Leppard, G¹, Blair, S³, ¹ Environment Canada, National Water Research Institute, Burlington, ON, Canada² Redlog Environmental Ltd, Bangrak, Bangkok, Thailand³ Consortium of International Consultants, Safat, Kuwait

ABSTRACT- In the 1991 Gulf War over 40 billion litres of oil were released. This oil spill was by far the largest in history. There are over 64 km2 of shoreline that are still contaminated. The anticipated recovery is taking about ten times longer than other studied oil spills. We were contracted by Consortium of International Consultants (CIC) from its client, Public Authority for Assessment of Compensation Resulting from Iraqi Aggression in the state of Kuwait (PAAC), to review the potential for bioremediation and to prepare submissions to the United Nations Claims Commission (UNCC). Only with nutrient enrichment were bacteria seen with an electron microscope to be commonly attached to oil. A pilot-scale injection of a solution containing nitrate and nutrients into intertidal sediments bioremediated highly weathered oil. After one month there was a notable production of alkanes resulting from either breakdown of larger more complex petroleum compounds or "liberation" of sequestered oil from a mineral precipitate matrix. Two months following the treatment, effectively all of the C8 to C40 compounds were reduced to very low levels equating to treatment effectiveness for aliphatics of about 90%. There was little washout of the nutrients. Impacts to benthos were limited and they fully recovered within three months.

Key words: bioremediation, weathered oil