Présentations Colloques

Oral Presentation
6.01
Session 6.01: Managed Aquifer Recharge
Marchina Chiara
Monitoring Water quality in Induced RIverBank Filtration- The case study of the Sant'Alessio plant (Italy)
Monitoring water quality (i.e. chemical, i.e. emerging contaminants, and biological analytes) prior to plant set-up and during ongoing operations are needed steps in order to assure safety of the Managed Aquifer Recharge schemes and to evaluate potential risks for the environment and humans.**The Serchio River Induced RiverBank Filtration (IRBF) MAR scheme in Sant'Alessio - Lucca (Italy) provides drinking water for about 300,000 people in coastal Tuscany. This scheme is constituted by ten vertical wells pumping from a high yield sand and gravel aquifer (10-2 m2 s transmissivity), and it includes a weir down-stream the well field to raise river head and to increase water storage in the aquifer along the river reach. Surface geology is characterised by unconsolidated silty to sandy sediments, while in the Serchio riverbed coarse clean gravels outcrop. **Currently this MAR plant is not yet routinely monitored in real - or quasi-real time for preventing risks of pollution of the abstracted groundwater. Within the EU FP7 MARSOL project a continuously monitoring network for T, EC and head along with nitrates, few organics and surface water quality fingerprinting has been set-up. This is backed up by discrete sampling for chemical analysis, including microbiology and pharmaceuticals. First results show that the most conservative elements such as Cl-, Br-, and SO42- clearly indicate mixing processes between the River Serchio water and groundwater in the pilot area. Sampled waters exhibit a bicarbonate-alkaline-earth hydrochemical facies whereas isotopic analyses of δ+18O and δ+D highlight that the Serchio River constitute most part of the groundwater recharge in the plain.**Pharmaceutical screening shows that stand-alone compounds concentrations are at present not of concern, aside from those determined in a ditch collecting untreated wastewater from the adjoining peri-urban area (i.e. Clarithromycine 6.9 Ig l, Atenolol 1.5 Ig l, Diclofenac 0.31 Ig l, Ibuprofene 0.78 Ig l, beta-Sitosterol 9.6 Ig l, Naproxene 0.6 Ig l ).**
Italy