Stochastic Simulation of Shallow Aquifer Heterogeneity and It’s Using in Contaminant Transport Modeling in Tianjin Plains

Abstract

Shallow aquifers of Tianjin Plain formed by alluvium, marine and lacustrine sedimentary sequences, and resulting complex structure impose challenges to modeling groundwater flow and contaminant transport in it. To solve the problem and prove its feasibility, this study utilizes TProGS (Transition Probability Geostatistical Software) to describe hydrogeological structure of engineering sites, and then simulates contaminant transport by integrated using MT3D (Modular Three-Dimensional Transport Model) with traditional layered assignment approach and transition probability geostatistical approach respectively. The results show that aquifer structure on local scale is effectively described by TProGS and there is a smaller plume distribution in modeling with transition geostatistical approach than that with traditional layered assignment approach, it’s also more in line with the groundwater flow direction. It illustrates the advantages of stochastic simulation in detailed conceptualization of hydrogeological structure. Furthermore, it demonstrates that integrated utilizing stochastic simulations and MT3D is more practicable than traditional approach in engineering practice for both probabilistic estimation of hydraulic conductivities and probabilistic assessment of contaminant plume capture at a heterogeneous field site.