Around the Ouro Preto region, State of Minas Gerais Brazil, there is a significant presence of topaz prospecting. This activity is characterized by the use of rudimentary techniques without any tailing disposal control. Among the environmental impacts are: deforestation, tailing generation and accumulation, introduction of suspended fine particulate matter to the water and silting up of streams. In this work a hydrochemical study was carried out aiming to assess the water quality of the Ponte River and its tributaries. Water samples were analyzed for pH, Eh, dissolved oxygen, electrical conductivity, turbidity, alkalinity, chloride, sulfate, metals (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Sc, Sr, Ti, V, Y and Zn) and suspended particulate matter. The results show that the main problem in the area is the high turbidity values, which are associated with the presence of suspended solids introduced by the prospecting activity (reaching a concentration of up to 2.9 g.L-1). This fact represents an important facto, since it demonstrates that metals are being deposited in the aquatic atmosphere.
Water; metals; particulate suspended matter; topaz prospecting
