Type Curves For Estimating Breakthrough Times Of Pollutants With First-Order Decay

Abstract

In low-permeability barriers that underline waste-disposal sites, diffusion (or dispersion) related to large-concentration gradients can be the primary mechanism of pollutant transfer to the environment. This paper presents type curves for the estimation of pollutant breakthrough times in the case of migration influenced by advection, dispersion, reversible sorption, and first-order decay. These type curves are constructed using dimensionless variables that combine barrier and pollutant characteristics. A set of type curves is derived for three values of relative concentration levels. One result is the identification of a “no-breakthrough envelope,” defined by points beyond which the relative concentration of interest never appears. The proposed type curves aim primarily at providing a graphical alternative for practitioners who are unfamiliar with the computer tools that are generally required to account for these transport phenomena.