This paper presents an analytical study of organic contaminants transport in a cut-off wall and aquifer dual-domain system, considering the effects of the inlet boundary conditions and cut-off structural arrangements. The comprehensive sensitivity analysis of parameters focusing on the breakthrough time, attenuation time and cumulative concentration are presented using the Monte Carlo simulation and Sobol global method. The simplified constant inlet boundary condition can lead to an excessively conservative prediction of the contaminant breakthrough compared to the ‘finite mass’ and ‘decaying source’ boundary conditions. The cut-off wall hydraulic performance can be enhanced by reducing the contaminant's head loss, shape factor, half-life and cut-off wall hydraulic conductivity while increasing the retardation factor. The contaminant's half-life can largely influence the maximum contaminant concentration, attenuation time and breakthrough time. For example, the maximum contaminant concentrations for T_1/2 = 1.4 years and T_1/2 = 100 years are 13 and 123 times greater than that for T_1/2 = 0.1 year, respectively. The influence of the variation of shape factor on the breakthrough curve should be taken into consideration. Altering the structural arrangement of the cut-off wall to accommodate a smaller shape factor increases the contaminant breakthrough time. The proposed solution allows the analysis of a cut-off wall and aquifer system with different inlet boundary conditions and structural arrangements of the cut-off wall.

本文提出了有机污染物在防渗墙和含水层双域系统中迁移的分析研究，考虑了入口边界条件和防渗结构布置的影响。采用蒙特卡罗模拟和Sobol全局法对突破时间、衰减时间和累积浓度等参数进行综合敏感性分析。与“有限质量”和“衰变源”边界条件相比，简化的恒定入口边界条件可能导致污染物突破的预测过于保守。可以通过降低污染物的水头损失、形状系数、半衰期和防渗墙水力传导率同时增加阻滞系数来增强防渗墙水力性能。污染物的半衰期很大程度上影响污染物的最大浓度、衰减时间和突破时间。例如，T _1/2  = 1.4 年和T _1/2 = 100 年的最大污染物浓度分别是T _1/2 = 0.1 年 的13 倍和123 倍 。应考虑形状因子的变化对突破曲线的影响。改变防渗墙的结构布置以适应较小的形状系数会增加污染物穿透时间。所提出的解决方案允许分析具有不同入口边界条件和防渗墙结构布置的防渗墙和含水层系统。