Soil quality protection at heavy metal-contaminated manufactured gas plant sites: Role of biological remediation

Soil contamination by metals has been a serious problem since the very beginning of the industrial revolution and nowadays causes widespread environmental concern. Most frequently, the results of soil pollution are due to phenomena of co-contamination (multi-metals or organic and inorganic pollutants) that have negative consequences for soil quality and require appropriate solutions for their reclamation. Remediation technologies have often used invasive processes that impact the characteristics of the soil substantially, causing the degradation of this important resource. The simultaneous presence of different metals is very common in MGP sites, and the remediation of these areas is technically demanding and requires suitable interventions at a reasonable cost. A case study is reported to evaluate both biological and nonbiological approaches used at a former MGP site. Two technologies have been compared in order to evaluate the best possible cost-effective strategies for the maintenance of high soil quality. Results suggest the applicability of biological strategies, in this case phytoremediation, thanks to the efficiency achieved with minimal disturbance of surrounding areas.