Arsenic in mining environments: evidences from Sardinia (Italy)

In Sardinia, the dispersion of arsenic in the environment appears strictly linked with mineralised bodies and mining activities. Currently, the areas of main concern are the active gold mine at Furtei, and the abandoned Pb- As mine at Baccu Locci. At Furtei, the main sources of arsenic are enargite, and arsenian pyrite; an ongoing monitoring program of water quality in the area around the mine documented so far no major changes with respect to pre-mine conditions, except for the formation of extremely acid, As-rich pit lakes. At Baccu Locci, the main primary source is arsenopyrite; arsenic dispersion is essentially due to the past unwise practice of discarding mine tailings into the nearby creek. Arsenic is slowly released from residual arsenopyrite and temporary secondary mineral traps such as Fe-oxyhydroxides, causing contamination of soils and waters as far as 10 km downstream of the mine

Environmental mineralogy and geochemistry of the abandoned Pb-Zn Montevecchio-Ingurtosu mining district, Sardinia, Italy

The Montevecchio-Ingurtosu mining district has been a major source of Pb and Zn since roman times and now contains approximately three million cubic metres of tailings with up to a few percent of Pb and Zn, several hundred ppm Cd and Cu, plus minor amounts of other metals. Since the cessation of all mining activities, these abandoned waste piles pose serious threats to the environment because they release toxic elements; waters draining the area are significantly polluted by Zn and Cd, and locally by Pb and Ni