Air Sparging is a commonly deployed environmental remediation technology by which pressurized air is injected into a contaminated groundwater zone to remove harmful volatile contaminants.  The injected air strips the contaminants from a liquid phase to a vapor phase and transports the volatile compounds via air channels to the unsaturated zone.
The extent of air distribution within the remedial zone of an air sparging site affects the level of contact between the air and the target contaminants and therefore is one of the primary factors leading to a site’s successful cleanup. Typically, the greater the uniform air distribution, the greater the contaminant removal rate.   Present systems use discrete depth air sparge wells to inject into the subsurface.  It has been demonstrated that by varying air injection depth using a composite set of wells, one is able to increase the level of air distribution and therefore significantly improve upon remedial performance.
The Navy has developed a new and innovative technology called Adjustable Depth Air Sparging (ADAS) that is applied within a single air sparge well with infinite adjustability. The technology has the capability to be used with conventional air sparging equipment and methods to help increase overall air distribution and therefore lower project costs and improve cleanup performance.
Results from a site demonstration conducted by XDD at a Superfund Site in NJ of the ADAS system will be presented.  Testing of the ADAS system showed that air could be injected at a variety of depth intervals in a single well by simply raising and lowering the technology’s packer system. The results confirmed that vertical adjustments to sparging depth clearly influenced and improved the achievable mass removal rate at the demonstration site.