Air dried subsurface samples of a heavy textured Red-Yellow Podzolic soil, representative of the industrial solid residue pilot landfill (ISRL) of the National Steel Works (Companhia Siderúrgica Nacional-CSN), were packed in 5.4 cm width and 37 cm high glass columns. An acid iron smelter residue was placed on the top of the soil columns to make a 4:1 soil-residue ratio, in consonance with the basic CSN project. To evaluate Cr, Mn, Ni, Cu, Zn, Cd and Pb mobilities, the system soil-residue was leached with 50 pore volumes of deionized water at pH 4.5. After leaching, the residue was removed from the tops and the soil columns were sectioned into 4 equal parts. The heavy metals in the residue and in the soil samples were sequentially extracted. Pb, Cr and Cu dissolved from the residues were retained in the upper 0-5 cm soil columns. Zn, Mn, Ni and Cd showed the same distribution pattern, i.e, increased concentration with depth. In the effluents leaching out the columns (with the residue on the top) the levels of Mn and Ni were higher than the standard limits allowed by FEEMA (1985).
heavy metal; steel works residue; landfill; leaching; metal mobility