The 'Kuil van Keet' Natural Attenuation Project

A special soil air movement (soil 'wind') sensor was developed for this project. After 3 months of R&D involving tenth or trial sensors which were tested at ultra low flow velocities (made by using 0,6 mm GC capillary glass tubing as laminar flow tubes) and creating ultra stable temperature compensation around the flow tubes, the 3 sensors installed at each level were finally tested to have a near linear response in the range from about 1 mm to 10 cm /hr air movement in soil. X and Y sensor installation is fairly simple, but the Z-vector requires special precousion to avoid rainwater infiltration to pass through the sensor. The solution was found in using an air permeable but hydrophobic membrane. The sensors worked well over the total project period and after excavation appeared still to have the same calibration curves. For results ask for full report (e-mail) or see under articles / publications at poster presented at Battelle's first contaminated sediments conference held in Venice Italy 10-2001.