Canadian Spill Response Organization

CSRO SERVICES

Surfactant Enhanced Bioremediation (SEB) of Oil Spill Contaminated Soils In Western Canada

Ivey International Inc. has over 20 years of experience in the bioremediation of petroleum hydrocarbons. This has included the successful biodegradation of mid to heavy end compounds known as the F2, F3, and F4 petroleum fractions which have a reputation for resisting bioremediation due to their sorption (i.e., absorption or adsorption) to the soil matrix which makes them less bio-available to the bacteria present. This resistance has given a negative reputation to the bioremediation of F3 and F4 compounds. In response to this problem, Ivey International Inc. completed a five (5) year research and development project that resulted in the development of non-ionic surfactant blends (Ivey-sol®) with a selective ability to desorb sorbed F2, F3 and F4 compounds. In doing so, the desorbed compounds are more bio-available to the microorganisms in the soil resulting in a rapid and cost effective degradation of these compounds. This process has come to be known as Surfactant Enhanced Bioremediation (SEB®).

Ivey International Inc. was retained to apply their SEB technology to treat >2000 tons of F2, F3, and F4 fine grained contaminated soil at a remote site in Northern, Alberta, Canada. The project was commenced in late August just prior to the on-set of colder northern weather in an area know for minus 20 oC to minus 40oC winter temperatures. The actual period for effective bioremediation in this climate is limited to only 4 to 6 months.

The SEB process was effective in achieving the soil remediation goals in <11 months, commencing with average baseline hydrocarbons concentration of F1 441 ppm, F2 1,189 ppm, F3 2,064 and F4 965. The total % reduction in each hydrocarbon fractions was: F1 (100%), F2 (92%), F3 (83%), and F4 (81%), achieving the applicable Alberta Environment Soil Remediation Guidelines (ABENV, June 2007).

SEB Soil Remediation Results

	F1	F2	F3	F4
August	441 ppm	1,189 ppm	2,064 ppm	965 ppm
February	2 ppm	376 ppm	1,107.5 ppm	347.5 ppm
July	N.D.	98.25 ppm	347.5 ppm	180 ppm

During the past decade, much discussion has centered on the unavailability of absorbed compounds to soil microorganisms. It is generally now assumed that desorption and diffusion of bound contaminants to the aqueous moisture phase is required for microbial degradation (W.P. Inskeep, J.M. Wraith, C.G. Johnston, Hazardous Substance Research Center, 2005). This reality limits the effectiveness of conventional bioremediation for treating absorbed F2, F3 and F4 contamination in soil. The SEB process has overcome this limitation permitting the rapid and economical biodegradation of recalcitrant F3 and F4 petroleum compounds.

For more information on Ivey International Inc. SEB soil treatment processes, please visit our web site at www.iveyinternational.com, or call our office at 1-800-246-2744.