How to Predict the Efficacy of Free-Product DNAPL Pool Extraction Using 3D High-Precision Numerical Simulations: An Interdisciplinary Test Study in South-Western Sicily (Italy)

Dense nonaqueous phase liquids (DNAPLs) are known to be denser than water and immiscible with other fluids. Once released into the environment, they migrate downward through variably saturated zone, causing severe damage. For this reason, it is essential properly develop a rapid response strategy, including predictions of contaminant migration trajectories from numerical simulations modeling. This paper presents series free-product DNAPL extraction by means purpose-designed pumping well. The objective minimize environmental impact caused release in subsurface, estimating recoverable DNAPL, depending on hydraulic properties aquifer medium, leaving residual that could act as long-term pollution source. Coupling bacterial community characterization (through biomolecular analyses), was verified (i) recovery (mainly PCE at study site) well would almost complete (ii) application remediation techniques (such bioremediation) not necessary remove source because (iii) natural attenuation process provided autochthonous community, which characterized genera Dechloromonas, Rhodoferax, Desulfurivibrio) have metabolic pathways capable favoring degradation chlorinated compounds.