Transverse vertical dispersivity in aquifer materials: Implications on mass transfer across the capillary fringe and the length of steady state plumes

Laboratory experiments on the effect of transverse mixing (diffusion and dispersion) on NAPL pool dissolution, vapor phase transport across the capillary fringe and biodegradation of contaminant plumes were performed and simulated with analytical and numerical models. Very small vertical dispersivities were encountered, which are critical values for the estimation of Natural Attenuation potentials. Based on transverse dispersion, methods for the estimation of contaminant plume size are discussed.