Assessment of the impact of contaminated soils from petroleum storage facilities on groundwater using column leaching experiment. – T. N. Nganje, A. E. Edet, S. J. Ekwere and A. N. Ugbaja
In this study, the column leaching experiment was used to assess the impact of contaminated soils from petroleum handling facilities on the quality of groundwater of the Calabar coastal plain sand aquifer. The study reveals that the total polycyclic aromatic hydrocarbons (PAHs) in the eluate is higher than the USEPA recommended limit of 0.2 μg/I. Secondly the total polycyclic aromatic hydrocarbons (PAH) in groundwater is higher than the values obtained from the column leaching experiment. This is attributed to the amount of material eluted in comparison to the aquifer material. The data also shows a decrease in the concentration of total polycyclic aromatic hydrocarbons (PAHs) and total organic carbon content (TOC) with time, indicating diffusion and limited desorption as the dominant transport mechanism. Moreover, more than 90% of the contaminants (PAHs) loaded into the columns were retained indicating the difficulties of groundwater remediation in the study area. The implication of this to groundwater contamination and remediation form the main theme of this article.