Consolidation of a large, 20-30-meter-deep landslide (about 1.700.000 m3) acting on a complex system of overlapping aquifers, by means of a drainage system installed along two microtunnels. The use of drainage tunnels is an innovative technique that allows a low environmental impact, minimizes the risk of landslides and gives the opportunity to regulate the flow of drains (by a valve) and eventually add new integrations.