We introduce a degenerate nonlinear parabolic-elliptic system, which describes the chemical aggression of limestones under the attack of SO 2 , in high permeability regime. By means of a dimensional scaling, the qualitative behavior of the solutions in the fast reaction limit is investigated. Explicit asymptotic conditions for the front formation are derived.

We present a numerical investigation of a degenerate nonlinear parabolicelliptic system, which describes the chemical aggression of limestones under the attack of SO 2 , in high permeability regime. This system has been introduced in the first part of this paper. We present a finite element scheme for our model and its numerical stability is given under suitable CFL conditions. Numerical tests are discussed as well as some examples of the numerical behavior of the solutions.