A Previsional Model to Estimate the Duration of Remedial Activities in Hydrocarbon Contaminted Acquifers

Phenomena of hydrocarbon contamination frequently occur in the areas of fuel stocking and distribution, like the many petrol stations widespread all over the territory of the industrialized countries. The risk deriving from uncontrolled release of fuels in the environment should be removed adopting the necessary safety measures. However, anytime spills from underground storage tanks accidentally occur, and where these determine excessive polluting concentrations in different environmental matrixes (soil and groundwater), it is necessary to proceed with the site remediation (Bonomo, 2000). Remedial technologies are then chosen accordingly to the specific characteristics of the pollutants, the soil and the groundwater when present. The aim of this work was a first attempt to build a theoretical predictive model to estimate the duration of remedial activities as a function of the contaminating typology and the hydrogeological characteristics of the site. The research has been developed, in terms of methodology, gathering information and analyzing data from remedial activities (site investigation and plant operation) carried out by Golder Associates S.r.l. on 20 hydrocarbon contaminated sites in Italy. The study was particularly addressed to evaluate the trends of concentrations of three substances that more frequently impact groundwater when fuel spills occur (Ducco, 2001), that is benzene (B), metil terbutil ether (MtBE) and the hydrocarbon compounds (aliphatics) with a low number of carbon atoms, expressed by the analytical parameter “total petroleum hydrocarbon” (TPH).