Forested Infiltration Area (FIA) Design in the Arborea Nitrate Vulnerable Zone (Sardinia, Italy)

This research aims to test a Managed Aquifer Recharge (MAR) technique based on Forested Infiltration Areas (FIAs) to reduce the groundwater nitrate contamination of a sandy phreatic aquifer in the Arborea NVZ (Sardinia, Italy). The FIA system in Arborea will be supplied with drainage water having an average NO3 concentration of 70 mg L−1, pumped from a dewatering pumping station. The water will be treated before infiltration through an innovative passive treatment system, consisting of a mixture of inert and organic materials, to attenuate organic and inorganic contamination and to prevent clogging processes at the infiltrating surface. The experiment will be conducted for a duration of two years. Monthly monitoring will define, ante operam, the quality baseline of drainage water and groundwater and will assess, post operam, the efficiency of the FIA system. An estimation of the infiltration rate in the sandy soils based on preliminary surveys showed a potential recharge rate of around 0.7 hm3 year−1 per 0.4 ha of the FIA system.