The mixed pollution of LNAPL and DNAPL is a common problem in environmental geotechnical engineering. Leakage, migration and extraction of pollutants will affect the distribution of pollutants in the unsaturation and the saturation zone. Furthermore, they will also affect the disposal efficiency of pollutants. The paper mainly focused on the migration of LNAPL under the influence of DNAPL. With the software of T2VOC, the distribution of pollutants under the whole process of “leakage-migration-extraction” was studied, especially about LNAPL. The studies showed that LNAPL will penetrate into the saturation zone through the unsaturation zone with the action of DNAPL, while it is only distributed in the unsaturation zone under the pure LNAPL condition. Meanwhile, with the increase of DNAPL quality ratio, the distribution area of LNAPL in the saturated zone increased accordingly. The study also indicated that extraction process will lead to the increase of LNAPL and DNAPL in some area. The results of the study have practical significance in revealing the migration of pollutants under the mixture conditions of LNAPL and DNAPL in engineering area.
