Physical (Sandbox) modelling of Melides demo site

Abstract

Workpackage 12 deals with modelling MAR solution’s implementation. To study the effectiveness of these solutions, Task 12.5 was conceived and developed using physical models - which represent the real case study sites in a small and controlled scale - to demonstrate the effectiveness of MAR, namely clogging issues and physic-chemical treatment of recharging water. Besides the physico-chemical treatment, the experiments were also numerically modelled with the same tools used to model the real cases, and in cooperation with Workpackage 14. To develop Task 12.5, a new physical sandbox model was built in LNEC’s modelling facilities (cf. http://www.lnec.pt/en/research/research-infrastructures/fluvial-hydraulics-experimental-facility/) under MARSOL project. The artificial aquifer facility (or physical sandbox model) can be used to conduct laboratory large scale infiltration and tracer tests, aiming to determine the soil infiltration rate and also the contaminants retention and/or degradation capacity, namely to simulate Soil-Aquifer Treatment (SAT) in a Managed Aquifer Recharge (MAR) basin. The DEMO site PT3 – Melides aquifer, river and lagoon (Alentejo) was selected to model and demonstrate soil-aquifer-treatment (SAT-MAR) to remove rice paddy field pollutants prior to their discharge into Melides lagoon. The results obtained in these tests gave the necessary knowledge to build, in the future, an in situ SAT-MAR facility.