Air Sparging

Air sparging is an in-situ technology used in the remediation of groundwater. It is generally used in conjunction with vapour extraction techniques and is known to have a positive effect on the unsaturated zone of the soil.

This methodology is used in the remediation of groundwater contaminated with volatile and some semi-volatile compounds.

Essentially this remediation process involves the drilling of injection wells into the water table. These wells are connected to a surface mounted blower unit which pumps air down the wells and into the groundwater. The air flushes - or bubbles - the contaminants into the unsaturated zone. It does so in much the same way as an air stripper volatilises contaminants from water where a further set of shallower wells installed into the unsaturated zone extract the vapours for discharge to atmosphere or further treatment such as activated carbon.

As with most in-situ technologies considerable importance is placed upon understanding the ground conditions and ensuring that the installation of both injection and abstraction wells are accurately placed and spaced.

The addition of oxygen to the formation and groundwater also enhances the biodegradation process and facilitates natural attenuation. The process tends to be of medium-to-long duration.

Please follow the link for further information and diagrams on air sparging.