Geochemical modeling as a tool to investigate the release and fate of Cr in the ophiolitic aquifers of Northern Calabria (S-Italy)

Teresa Critelli (*), Carmine Apollaro (*), Giovanni Vespasiano (*) & Rosanna De Rosa (*)
(*) Department of Biology, Ecology and Earth Sciences, University of Calabria, Via Ponte Bucci 4, cubo 15B, 87036 Arcavacata di Rende (CS), Italy. E-mail: first.teresa.critelli@unical.it

The study of the weathering process of ophiolitic rocks represents an important process due the high toxicity of Cr(VI) with environmental and social consequences and health effects. Since this topic is not well understood, a preliminary study on the release of Cr and other constituents during the weathering of the meta-ophiolitic rocks outcropping in Northern Calabria (Fuscaldo zone) has been carried out using the reaction path modeling. In this work, the EQ3/6 software package, version 8.0 was used together with its data0.ymp.R5 thermodynamic database (Apollaro et al., 2013a, b), upon acquisition of the necessary information such as the stability constants of the aqueous complexes of Cr(VI). Preliminary results showed that the geochemical modeling is an important tool to investigate the phenomena which control the redox state of Cr in near-surface environment and the release and fate of Cr and other chemical constituents in these peculiar environments since during the progressive dissolution of the considered lithotypes, the aqueous solution may attain saturation with respect to different secondary solid phases, potentially acting as sinks of various elements and species.

EQ3/6, Cr (VI), geochemical modeling