In-situ pressure and flow sensor monitoring of air sparging

A pilot scale air sparging operation was initiated in October, 1996, to determine the physical characteristics and effects of air injected into the saturated zone through a single sparge point. 7-micormachined pressure sensor staffs and 7 in situ permeable flow sensors were positioned at different depths and distances surrounding the sparge well. In situ pressure sensors were deployed in the subsurface at regular intervals on PVC pipes, to define pressure differentiation within the sparge area and define water and oxygen transport from the sparge region. In situ flow sensors were deployed in the subsurface in a linear design directly up gradient and down gradient from the sparge point at different depths in order to monitor groundwater flow patterns, possible convection cells, mounding effects, and contaminant distribution sparge effects. The entire sensor system is automated with a data acquisition system for remote operation and data transfer.