ABSTRACT
Natural attenuation of explosives may occur through microbial mineralization, microbial transformation, and/or immobilization. A demonstration of natural attenuation of explosives was conducted at a former waste lagoon area, at the Louisiana Army Ammunition Plant (LAAP). Objectives of the demonstration were to establish through appropriate site monitoring that natural attenuation is occurring, to develop guidance for selection of monitored natural attenuation as a remediation alternative, and to develop a protocol for implementation of monitored natural attenuation. Trends in contaminant concentration were generally static to declining over time. Results of batch and column tests indicated that the soils at LAAP have low sorptive capacity and slow transformation rates for the explosives. Initial biomarker results indicate low levels of direct and cometabolic microbial activity against explosives. A protocol which addresses selection, implementation and regulatory issues associated with monitored natural attenuation of explosives was developed.
