Analytical model for organic contaminant transport in a cut-off wall and aquifer dual-domain system considering barrier arrangements

Haijian Xie; Yanghui Shi; Huaxiang Yan; Abdelmalek Bouazza; Xianghong Zhu; Ao Wang

doi:10.1016/j.jconhyd.2023.104259

Analytical model for organic contaminant transport in a cut-off wall and aquifer dual-domain system considering barrier arrangements

J Contam Hydrol. 2023 Nov:259:104259. doi: 10.1016/j.jconhyd.2023.104259. Epub 2023 Oct 30.

Authors

Haijian Xie¹, Yanghui Shi¹, Huaxiang Yan², Abdelmalek Bouazza³, Xianghong Zhu⁴, Ao Wang¹

Affiliations

¹ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China; Center for Balance Architecture, Zhejiang University, 148 Tianmushan Road, Hanghzou 310007, China.
² Center for Balance Architecture, Zhejiang University, 148 Tianmushan Road, Hanghzou 310007, China; The Architectural Design and Research Institute of Zhejiang University Co. Ltd., 148 Tianmushan Rd., Hangzhou 310058, China. Electronic address: yanhuaxiang@zju.edu.cn.
³ Department of Civil Engineering, Monash University, 23 College Walk, Vic 3800, Australia.
⁴ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China.

PMID: 37922726
DOI: 10.1016/j.jconhyd.2023.104259

Abstract

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.

Keywords: Analytical model; Boundary condition; Cut-off wall; Decaying source; Monte Carlo simulation; Shape factor.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Computer Simulation
Groundwater*
Models, Theoretical*
Monte Carlo Method
Water Movements