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

The University of Alaska Fairbanks Environmental Technology Laboratory is conducting ongoing research into the effectiveness of a biosurfact ant, 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 LaTou che Island in Prince William Sound. The results of chemical analysis o f the beach material before and after treatment show that diesel range petroleum hydrocarbons are completely removed to levels below the det ection limit of 0.5 mg kg(-1). Semivolatile petroleum hydrocarbons wer e reduced an average of 70%. The microbial data collected indicate tha t no inhibition of microbial activity in sediments is caused by treatm ent. The numbers and activity of hydrocarbon-degrading organisms were enhanced immediately following treatment and for about a month afterwa rds. There was no evidence of dissolved hydrocarbons or increased micr obiological activity in seawater samples, providing evidence that oil was not transported offshore during the treatment process.