Abstract: Multi-phase extraction (MPE) technology is commonly used for soil and groundwater remediation. Optimizing well locations for efficient, low-carbon and cost-effective remediation is crucial to the further development of MPE technology. In this study, a self-developed MATLAB-TMVOC joint optimization program was used to optimize the horizontal location and screen opening position of the extraction wells in a simulated benzene-contaminated site. The influence of soil permeability on the layout plan of extraction wells was also investigated. The results showed that the MATLAB-TMVOC joint optimization program exhibited rapid and efficient characteristics. It eliminated the complex manual parameter adjustment process, saved more than 50% of simulation time and reduced more than 90% of simulation compared to manual optimization. The optimized spacing between extraction wells decreased with decreasing soil permeability. For the model constructed in this study, when the soil permeability was within the range of 2×10⁻¹³ m² to 8×10⁻¹² m², a decrease of 10⁻¹³ m² in soil permeability led to a reduction of 0.13 m in the optimized spacing between extraction wells. With a decrease of one order of magnitude in soil permeability, the spacing between extraction wells should be reduced by 17.8% to 48.3%. For cohesive formations with soil permeability below 10⁻¹³ m², the spacing between wells in the core area of the pollution plume should be less than 4 m. The optimized remediation plan can reduce costs and carbon emissions. When the target removal rate is set at 90%, the optimized MPE remediation plan can save 29.7% to 34.7% of operational costs, 22.7% to 29.3% of total costs, and 21.4% to 40.4% of carbon emissions. The study revealed that the arrangement of MPE remediation wells in contaminated sites should be combined with site permeability and pollution plume distribution, and a non-uniform well layout plan from dense to sparse in the direction from the pollution source to the tail of the pollution plume in order to achieve effective and low-carbon remediation.