The current study focuses on developing alternative formulations (mobile-immobile model) of transient analytical modelling for organic contaminant transport in a composite of geosynthetic clay (GCL) and attenuation layer (AL) system. The Laplace transform method is adopted to derive the solution. The proposed analytical frameworks are validated by two set of benchmarks. The varied examples of organic contaminant transport in the composite liner are evaluated by the proposed solution to discuss the effects of soil properties, flow conditions, adsorption, and mass transfer in mobile and immobile zones on the overall transport of contaminants. Finally, an example case is presented to show the application prospect of the proposed model. The result demonstrated that mass transfer between mobile and immobile may increase the breakthrough time by a factor of 2. This indicates that heterogeneities of clay are a non-negligible part for the performance assessment of the liner system. Péclet number in GCL (\({P}_{g}\)) is used to investigate the relative importance of advection and diffusion mechanisms. Increasing \({P}_{g}\) from 0.1 to 1 can lead to an increase of the breakthrough time by a factor of 15. The analytical solutions presented here may also serve as the basic benchmark test tool for alternative numerical studies of contaminants transport in heterogeneous media.

目前的研究重点是开发土工合成粘土（GCL）和衰减层（AL）系统复合材料中有机污染物迁移瞬态分析模型的替代公式（移动-固定模型）。采用拉普拉斯变换方法求解。所提出的分析框架通过两组基准进行了验证。通过所提出的解决方案评估了复合衬里中有机污染物传输的各种示例，以讨论移动和固定区域中的土壤特性、流动条件、吸附和传质对污染物总体传输的影响。最后，给出了一个算例来展示该模型的应用前景。结果表明，移动和固定之间的质量传递可能会使突破时间增加 2 倍。这表明粘土的非均质性是衬管系统性能评估中不可忽视的部分。GCL 中的佩克莱数 (\({P}_{g}\) ) 用于研究平流和扩散机制的相对重要性。将\({P}_{g}\)从 0.1 增加到 1 可以导致突破时间增加 15 倍。这里提出的解析解也可以作为替代数值研究的基本基准测试工具。污染物在异质介质中的传输。