Numerical assessment of the passivator effectiveness for Cd-contaminated soil remediation

A highly effective, economical, and reliable remedial technology is imperative for the successful remediation of [1] cadmium (Cd)-contaminated soil. Although certain Cd passivators have been found to be effective, the methods of assessing their effectiveness are very limited and rarely studied. This study aimed to develop a practical score method for assessing the remedial effectiveness of the Cd passivator. Ultimately, 16 evaluation indexes, 36 weight coefficients, 16 utility functions, and an evaluation system set were obtained. The repair effect of passivator was analysed according to four aspects: metal pollution, soil fertility, passivator cost-effectiveness, and crop profit. The numerical score scale ranged from 0 to 1, with a higher score being indicative of higher remedial effectiveness. There were five repair levels: level 1-5. Level 1 was optimal, and level 5 the poorest. In addition, this study suggested and designed the structure of a passivator database composed of soil information, the remediation effectiveness of the passivator, and the evaluation method. This study provides more comprehensive and insightful information to guide improved soil remediation and soil contamination control.