Abstract

The commune of Andacollo is located in the Coquimbo region in northern Chile. It has an area of 310 km2 and a population of 11,044 inhabitants. According to the National Tailings Cadastre 2020 of the National Geology and Mining Service, there are a total of 743 tailings in Chile, of which 105 are located in Andacollo. As mentioned above, according to the Ministry of Mining, tailings are defined as a residue, a mixture of ground ore with water and other compounds, left over from the extraction of sulfide minerals in the flotation process. In the tailings visited during the field campaigns conducted in 2019 and 2020, sediment samples were collected, and it was evident through measurements made with portable XRF equipment, that several of the samples collected contained concentrations of heavy metals above the United States Environmental Protection Agency regulations. The sources of contamination, that is abandoned tailings deposits, are exposed to propagation in the environment through the dynamics of various physical factors. Given the relevance of these phenomena, it is essential to have a precise knowledge of the concentration and distribution of elements potentially harmful to the health of the population. Therefore, this study presents a geostatistical model of the spatial distribution of arsenic and lead on the surface of abandoned tailings deposits in Andacollo.