EFFECTIVENESS OF A BIOSURFACTANT IN REMOVING WEATHERED CRUDE-OIL FROM SUBSURFACE BEACH MATERIAL

The University of Alaska Fairbanks Environmental Technology Laboratory is conducting ongoing research into the effectiveness of a biosurfactant, PES-51(R), in removing weathered crude oil from beach material. A field test was conducted from 1 to 7 July 1993 in Sleepy Bay on LaTouche Island in Prince William Sound. The results of chemical analysis of the beach material before and after treatment show that diesel range petroleum hydrocarbons are completely removed to levels below the detection limit of 0.5 mg kg(-1). Semivolatile petroleum hydrocarbons were reduced an average of 70%. The microbial data collected indicate that no inhibition of microbial activity in sediments is caused by treatment. The numbers and activity of hydrocarbon-degrading organisms were enhanced immediately following treatment and for about a month afterwards. There was no evidence of dissolved hydrocarbons or increased microbiological activity in seawater samples, providing evidence that oil was not transported offshore during the treatment process.