Gallini, L., F. Ajmone-Marsan, and R. Scalenghe.
Journal of Geochemical Exploration 186:121-128(2018)

Four decades after cessation of 150 years of ore processing, researchers investigated an area downwind from a decommissioned iron smelter for signs of metals contamination and if any were found to evaluate the options for intervention. Samples taken from topsoils over an area of 15 km² near the pollution source showed total concentrations of 101 mg Cr, 8 mg Co, 41 mg Ni, 70 mg Cu, 143 mg Zn, 6 mg As, 1.3 mg Cd, 0.5 mg Sb, 92 mg Pb, and 1.3 mg Bi kg/soil, with standard errors exceeding 50%. Results indicate that it is unlikely soils in the vicinity of the former smelter are a source of disproportionate human metals intake. Considering a minimum area of 1 km² and a minimum depth of 10 cm, the total cost of soil removal with subsequent reclamation would be about one quarter of the local municipality's annual budget. Economically feasible options for reducing any risks would likely rely on optimization of risk assessment factors by adopting soil conservation practices. http://metallipesanti.altervista.org/Pubblicazioni/Gallini_Ajmone_Scalenghe_2018.pdf