Chromium and nickel in the soils of industrial areas at Asopos river basin

Abstract

The purpose of this paper is to present and compare previous efforts aiming to investigate whether previous wastewater disposal practices in selected (four) metal finishing facilities, located at Asopos river basin (near Athens at East-Central Greece), and resulted in relevant soil contamination. The work is focused mainly on Cr and Ni, which are the primary elements of concern in the Asopos river Basin area. To assess the natural geochemical levels of Cr and Ni, 30 soil samples were collected from locations that were assumed free of contamination. In these 30 soil samples, Cr concentration varied from 60 to 418 mg/kg, and Ni concentrations varied between 91 and 1200 mg/kg. A second group of soil samples consisted of more than 100 samples from drill cores and surface soil samples, assumed affected by the disposal of effluents of the metal finishing facilities and/or the relevant drainage of runoff water. A third group of samples consisted of 10 more surface soil samples collected in summer 2015 (campaigns by Sybilla ltd in the framework of EU IED Directive Baseline Site Investigation Study for two metal finishing units). The above mentioned groups of data were evaluated and compared with a fourth group of data (collected from Inofyta industrial area in the framework of EU funded project LIFE-CHARM “Chromium in Asopos groundwater system: Remediation technologies and Measures”). The conclusion of this study is that there is no indication of downstream pollution migration from the land-based treated effluents disposal of the above mentioned metal finishing facilities. Cr and Ni concentrations in the lower soil layers were of the same order of magnitude to those of the reference soils. On the contrary Inofyta Industrial Area soil seems to be rather contaminated and requires special attention.

Keywords

• Asopos River Basin pollution
• soil contamination
• hexavalent chromium
• nickel
• metal finishing effluents