Chemical speciation of heavy metals in soils by use of XAFS spectroscopy and electron microscopical techniques

Pb-contaminated soil samples were investigated using XAFS spectroscopy and SEM/EDX as tools for the analysis of chemical binding forms. The soils orig inated from the vicinity of a battery factory in Hannover (Germany) and had Pb-contents between 50 g/kg and 130 g/kg. PbCO3, PbSO4, PbO and basic PbCO 3 could be identified as the main constituents in the samples by XAFS spect roscopy (EXAFS as well as XANES). This result is consistent with the result s of the SEM/EDX investigations on the same soil samples, which showed, tha t almost all of the lend contained in the soils appears in the form of disc rete particles of lead compounds. The EDX analysis of these particles consi stently shows the presence of Pb, C, O and S.