One-dimensional radionuclide migration for convective water transport with sorption and longitudinal dispersion is investigated. A semianalytic solution for layered media with piecewise constant parameters can be written when taking into account mass conservation and approximate flux conservation at interlayer boundaries. The solution is analytic in the first layer and allows for a recursive calculation in the following layers. Scaling laws for the relevant parameters can be formulated. Numerical examples exhibit the importance of at least a single highly sorbing layer. Small values of dispersivity may not lead to a conservative estimate of concentration at the geological column’s end.