LNAPL Retention in Sandy Soil

Abstract

Abstract The vertical distribution of free and residual aviation gasoline, a light nonaqueous phase liquid (LNAPL), through the capillary fringe of a uniform, medium sand is measured and used to calibrate an existing model. The total saturation profile is governed by a classical moisture retention characteristic, with the matric pressure head scaled by LNAPL/air surface tension in the presence of free LNAPL and water/air surface tension in the absence of free LNAPL. The residual LNAPL is described by an empirical equation reflecting hysteretical trapping due to a fluctuating water table. The existing theory is calibrated with new and published field data at an aviation gasoline spill site in Traverse City, Michigan.