[A-HW28] Hydrology and Water Environment

[AHW28-P09] Application of MUSt for Simulating Reactive Transport of Coexisting Solvent Contaminants Considering Remediation of an NAPL Source in Groundwater

*Ching-ping Liang¹, Jui-Sheng Chen^2,3,4, Zhong-Yi Liao^2,3, Cheng-Wen Chen² (1.Fooyin University, 2.Graduate Institute of Applied Geology, National Central University, 3.Center for Advanced Model Research Development and Applications, National Central University, 4.Department of Earth Sciences, National Central University)

Keywords:MultiSpecies Transport (MUSt) , Chlorinated Solvents , Non-Aqueous Phase Liquid (NAPL) , Remediation

MUSt (MultiSpecies Transport analytical model) is an advanced software package designed for the analytical modeling of reactive transport involving multiple contaminants at sites impacted by chlorinated solvents. It provides environmental scientists and engineers with intuitive modeling techniques and robust visualization capabilities. MUSt incorporates three distinct source functions at the inlet boundary: constant, exponentially decaying, and piecewise constant.
This study applies MUSt to simulate the reactive transport of coexisting solvent contaminants while considering the remediation of a non-aqueous phase liquid (NAPL) source in groundwater. The simulation scenario follows Tutorial 6 from the REMChlor user manual. Using the piecewise constant source concentration function, simulation results are validated against a previously developed three-dimensional analytical model that assesses site remediation involving both the NAPL source and the downgradient contaminant plume.
The time-dependent source function in the previously derived analytical model, known as the power function, is formulated based on initial source mass, initial source concentration, source decay rate constant, and empirical parameters. The results from both simulations exhibit a high degree of consistency, demonstrating that the piecewise constant source function in MUSt can be effectively applied by using monitoring source concentrations at different time intervals in the field.