Distinguishing potential sources for As in groundwater in Pozuelos Basin, Puna region Argentina

NORDSTROM DARRELL KIRK; DOLD BERNHARD; MURRAY JESICA; KIRSCHBAUM ALICIA

Stockholm

Congreso; VI International Congress on Arsenic in the Environment (As2016); 2016

Groundwater is the main source of drinking water for the inhabitants in Pozuelos Basin, in most cases the As concentrations are above WHO guidelines (8.22- 113 μg/L). This study considers three potential sources for As in groundwater i) oxidation of As sulfides in Pan de Azúcar wastes, and acid mine drainage discharge on the basin (0.7 - 44 mg/l As); ii) weathering and erosion of rich gold mineralized shales and iii) weathering of volcanic eruptive non-mineralized rocks located in the headwater of some of the streams. High evaporation rates that characterize a prolonged dry season in the basin most probably favors As concentration increase in groundwater and in Pozuelos Lagoon.