Table 2.

Advantages and disadvantages of the available remediation techniques for metal-contaminated soils.

Method	Remediation technique	Advantages	Disadvantages	Reference
Physical remediation	Soil washing	Simple technology	High cost, installing solutions, collection wells, or underground drains may be difficult	Rajendran et al., 2021
	Surface covering	Easy to install, low cost, and high security	Limited to a small area, the soil loses its natural environmental function	Liu et al., 2018
	Soil replacement	Fast to implement and high efficiency	High cost, limited to seriously polluted small-scale soil	Rajendran et al., 2021
	Encapsulation	High security and fast install	High cost, limited to small and shallow contamination areas	Li et al., 2019
Chemical remediation	Thermal remediation	Simple process and thorough treatment	Large energy consumption and secondary pollution	Gong et al., 2018
	Vitrification technique	High efficiency	High cost, limited to small soil area, treated land and soil losing environmental functions	Dhaliwal et al., 2020
	Chemical fixation	Fast to implement, high efficiency	High cost and limited application site	Nejad et al., 2018
	Electrokinetic remediation	Economical and efficient	Limited to low permeability soils	Singh and Prasad, 2015
Bioremediation	Phytoremediation	Low cost, eco-friendly, almost no side effects	Slow process, low efficiency, and long cycle	Liu et al., 2020
Microbial bioremediation	Remove the contaminants, soils retain their properties and could be replaced on the reclaimed site	Microbes are easily affected by soil’s physical and chemical properties	Grover et al., 2021