Abstract:

The cChange in the spatial dimension of heterogeneous media significantly influences the migration and distribution of
Dense Non-Aqueous Phase Liquid (DNAPL). Based on the Markov Chain transition probability model, we generate stochastic
permeability fields and take a fully account of horizontal spatial continuity, asymmetry, and anisotropy of heterogeneous media. By simulating the migration and distribution of DNAPL in heterogeneous media with TMVOC-MP, we investigate the effects of horizontal spatial continuity, reduced dimensionality, and lateral migration on the migration and distribution of DNAPL. Numerical analysis reveals that a better horizontal spatial continuity results in a larger horizontal pollution scope and a smaller vertical migration extent of DNAPL. Compared with the behavior in the three-dimensional model, DNAPL distributes in a larger scope in the horizontal direction, accumulates more on the low-permeability lenses, and is mostly in a pool state in the two-dimensional model. Lateral migration process can reduce the impact of heterogeneity of a single plane on the DNAPL migration. So it is necessary to use the threedimensional model in practical applications instead of two-dimensional model.

Key words: DNAPL, heterogeneity, horizontal spatial continuity, physical dimensionality, lateral migration