Experimental application of two remediation technologies to mercury contaminated soils from the Almaden mining district (Spain)

摘要

This work is a comparative study between two remediation technologies: flushing and electmkinetic. For this purpose, samples from the Worlds largest mercury mining region were taken. The flushing and electrokinetic assays were performed in lab columns of 50cm<'2> cross section and 20cm length, which approximately contents 2kg of contaminated soil saturated with water. In addition, the BCR sequential extraction procedure (Ure,1993) was performed both in the original contaminated soil and at the lixiviated samples, in order to evaluate the mobility and availability of the mercury in the soil before and after the remediation. It was observed that after the remediation treatments, the mercury was effectively removed from the fraction of Hg associated to the reducible matter, whereas the one associated to the oxidizable matter was not noticeably affected. In addition, if the treatment is not completely accomplished, the mobility of mercury in the contaminated soil would increase, as can be concluded from the relative increase of Hg associated to the weak acid soluble fraction obtained.