Using radon as tracer for Non-Aqueous Phase Liquid (NAPL) contamination.

Abstract

This study is related to a new analysis technique for hydrocarbons polluted sites through the use of Radon gas. In industrial areas and in areas where refineries and storage units for hydrocarbons are present, hydrocarbons spills in the subsoil may frequently occur. Hence the need for hydrocarbons remediation actions. In this study the importance of Rn lies in the fact that it has excellent solubility in a wide range of NAPL, so as to form negative anomalies concentration in the soil where the presence of these pollutants is observed. In this way, knowing the soil Radon concentrations in the background area, an area polluted by NAPL could be indirectly localized by making a grid of surface Radon measurements over the area where it is assumed that NAPL pollution occurred. Radon solubility in NAPLs can be quantified for each NAPL with an individual NAPL/air partitioning coefficient (K NAPL/AIR). The partitioning coefficient K NAPL/AIR is one of the most influential parameters governing the decrease of gas radon concentration in the soil in the presence of NAPLs.