Ecological remediation strategy for urban brownfield renewal in Sichuan Province, China: a health risk evaluation perspective

Urban brownfield sites are abandoned industrial land and their redevelopment may be affected by environmental pollution, as the latter may pose health risks for residents. In this study, six heavy metals (Pb, As, Cr, Zn, Ni, and Cu) were examined from 87 soil samples extracted from four land use types (industrial area, residential/commercial area, traffic area, and agricultural area) in the Mianyang thermal power plant area, Sichuan Province, China. The soil contamination and environmental risk were evaluated using the single factor index, geo-accumulation index and Human Health Risk Evaluation. ArcGIS was used to map out the spatial distribution of heavy metal concentrations and environmental risk. The results of these analyses have indicated that different land use types have significant effects on the heavy metal contamination of soil. There are 10 non-carcinogenic risk areas of heavy metals in industrial land, while in the other three types there are 9 non-carcinogenic risk areas of heavy metals. Under the brownfield renewal planning, the present study scheme provides an effective method of discernment for ecological remediation of soil heavy metals. In addition, it can aid brownfield in finding different remediation strategies with economic benefits for different risk levels of human health.