The direction of this research was to modify current technology by maximizing soil retention and biological activity with a soil biofilter. The results clearly indicate a biofilter provides a barrier to volatile emissions while allowing hydrocarbon mineralization. The rate and manner of VOC removal were strongly influenced by operating conditions.
Little data is currently available to evaluate gasoline removal in unsaturated soil.
This research provides laboratory data on the sorption, volatilization and biodegradation pathways for 16 common gasoline constituents. It also considers the effect of variations in soil organic matter, contaminant concentration, soil moisture and depth of soil cover. Earthworm casts were used in evaluating the effect of increased organic matter. The influence of biofilter depth was evaluated by applying synthetic gasoline at different depths. An accounting of the gasoline removed by the various pathways was accomplished through a mass balance of total carbon.