Background The soil has been degraded as a result of the presence of an old mine located in the endorheic (closed) basin of Los Tollos lagoon. The open cast mine, which functioned in this area from 1976-98, extracted attapulgus (a natural biodegradable absorbent used in industry and for cat litter) in several places. Los Tollos is one of the most environmental valuable lagoons in Andalucía. Since 1986, it has been included in the “Plan Especial de Protección del Medio Físico de la Provincia de Cádiz” and currently is a designated Special Area of Conservation (SAC). Before the advent of mining, the area was an important site for numerous bird species, including several threatened species, such as the marbled duck (Marmaronetta angustirostris), white-headed duck (Oxyura leucocephala), and red-knobbed coot (Fulica cristata). Objectives The LIFE project’s main objective is to restore the topography and recover the degraded soil in the endorheic basin of la laguna de Los Tollos and surrounding areas. Other objectives are to: Eliminate the connection between the surface aquifer (saline) and the freshwater aquifer; Re-establish the surface hydrology processes; Re-establish the lake’s natural hydro-period; Re-establish the lake’s habitat and biodiversity function; Control the erosion of the endorheic basin; Prevent diffuse contamination of the lake's water; Increase the environmental value of the catchment basin by improving the habitat's biodiversity; Integrate the degraded area into the urban centre of El Cuervo; and Value the area as a destination for tourism and environmental education. Expected results: Restoration of the endorheic basin to achieve a state similar to that existing before the mining operation. The hydrogeological processes will be re-established, eliminating the connection between the saline surface aquifer and the fresh water aquifer of the pliocene sands; Reduction of diffuse contamination of the lake water generated by agricultural activity through a perimeter vegetation band; Prevention of lake silting by controlling sediments provided by the river network; Establishment of forest uses in the catchment basin in order to change the run-off dynamics of water, bringing it back to that existing before agricultural intensification; Re-establishment of the lake’s ecological processes (including its natural hydroperiod) and resalinisation of the substratum, which will allow the lake’s biological communities to develop; and Re-establishment of the ecological processes in the catchment basin. Introduction of forest uses (copses and enclosures) in an agricultural environment will make it possible to establish plant protection areas where insects and herbaceous flora can develop. Both communities provide food for the area’s fauna. Another related measure is the generation of spaces for breeding, such as installations for fauna and ligneous vegetation.