VERIFICATION OF TRAVEL TIME PROBABILITY DENSITY-FUNCTIONS FOR SORBING SOLUTES IN GROUNDWATER

It is important to characterize the movement and travel times of contaminants in groundwater for drinking water and soil quality purposes. For example, if a contaminant is released in the groundwater near a drinking water well, it is useful to know how long the contaminants will take to reach the well. Contaminants can be present in groundwater in the form of aqueous solutes or as sorbed phases. A travel time probability density function (PDF) describes the random time at which a contaminant particle will be at the location of interest. For solutes that can sorb, each particle can be either in the aqueous or sorbed phase so separate travel time PDFs are developed for each phase. We verify theoretical expressions for sorbed phase travel time PDFs by comparing them to results of finite difference (MODFLOW and MT3D) and random walk simulations.