Alto Loa National Reserve was created in 2005 after years of negotiations with mining companies Codelco and SQM (Sociedad Química y Minera de Chile), both of whom held concessions to much of the area. The Reserve covers approx 277,000 hectares of high altitude volcanic puna desert between Calama and Ollagüe in the Antofagasta Region and includes much of the upper watershed of the Loa River (a vital source of water for the Calama region) and the Ascotan and Carcote salt flats.