Life cycle assessment-based decision-making for thermal remediation of contaminated soil in a regional perspective

Abstract

Optimizing decision-making to reduce the environmental impact of remediation activities is critical for green and sustainable remediation. Currently, the environmental impact assessment for remediation technologies is primarily based on site-specific data, which makes the assessment results difficult to apply to different site conditions. In our study, an abandoned rubber factory site in the Jiangsu Province of China was used as an example to evaluate the life cycle impact of three frequently used soil remediation strategies including cement kiln co-processing, onsite ex-situ thermal desorption, and offsite ex-situ thermal desorption. The results show that when considering the subsequent disposal of contaminated soil after remediation, the environmental impacts of remediating 1 ton of contaminated soil decrease according to the following order: offsite ex-situ thermal desorption, onsite ex-situ thermal desorption, and cement kiln co-processing. The results also indicate that contaminated soil volume and transport distance profoundly affect the environmental impacts of contaminated soil remediation. Based on these findings, we proposed a generalized method for selecting the most environmentally friendly remediation technology under various site characteristics. Within the developed method, we examined remediation options for 43 sites contaminated by organic chemicals in Jiangsu Province. The simulation results suggest that the optimized remediation options could have reduced environmental impacts by as much as 61.1%. Our study provides insights and valuable information for reducing remediation decision-making costs and promoting sustainable remediation of contaminated soil on a regional scale.