Print this pageThe presence and fate of residual crude oil in soil and groundwater at a release site was investigated to determine the significance of natural attenuation processes. A biotreatability analysis of the soils and a biochemical analysis of the groundwater was completed to demonstrate and quantify intrinsic remediation of the residual hydrocarbons. The site soils were found to contain metabolically active microorganisms whose metabolic needs for oxygen characterizes them as either aerobic or facultatively anaerobic. Biochemical analysis of site groundwater provides evidence of active intrinsic remediation and the stabilization of the plume over a relatively short distance from the release area. Site data suggest that biodegradation of residual crude oil is occurring through both aerobic and anaerobic processes with aerobic respiration, sulfanogenesis, and methanogenesis all being important degradation mechanisms. Sulfanogenesis was found to be largely responsible for the total assimilative capacity of the aquifer to degrade hydrocarbons. The results of this study demonstrate that intrinsic bioremedation can provide a remediation alternative that is as efficient as actively engineered processes such as pump and treat.
AAPG Search and Discovery Article #90926©1999 AAPG Eastern Section Meeting, Indianapolis, Indiana