In the upper-middle catchment basin of the river Rio Flumendosa that feeds the 300 Mm3 reservoir of Lake Medio Flumendosa a number of major and minor ore bodies occur, some of which have been known since the Bronze Age and explored and exploited up to a few years ago. The products of this activity include open-pit and underground excavations and related dumps, and dressing-plant tailings. The long-lasting chemical and mechanical weathering has sent large quantities of heavy metals into the alluvium blankets along the streams and in the lake sediments. In these sediments total heavy-metal contents (mainly Pb, Zn, Cu, As and Cd) reach a few thousand ppm. A geochemical study has located the main pollution source in the basin of Rio Saraxinu, where the Cu-Pb-Zn mine of Funtana Raminosa operated starting from proto-historical times. Fro the dumps and dressing plants tailings of this mine, abundant ore mineral clasts and metal ions have entered the stream and lake sediments. Since an important share of the Lake Medio Flumendosa water is destined to civil uses, interventios aimed at monitoring the metal supply and eliminating water contamination risks are necessary.
heavy metal pollution risks after mining activity in the rio Flumendosa basin, Sardinia, Italy
S Fadda;M Fiori;
2002
Abstract
In the upper-middle catchment basin of the river Rio Flumendosa that feeds the 300 Mm3 reservoir of Lake Medio Flumendosa a number of major and minor ore bodies occur, some of which have been known since the Bronze Age and explored and exploited up to a few years ago. The products of this activity include open-pit and underground excavations and related dumps, and dressing-plant tailings. The long-lasting chemical and mechanical weathering has sent large quantities of heavy metals into the alluvium blankets along the streams and in the lake sediments. In these sediments total heavy-metal contents (mainly Pb, Zn, Cu, As and Cd) reach a few thousand ppm. A geochemical study has located the main pollution source in the basin of Rio Saraxinu, where the Cu-Pb-Zn mine of Funtana Raminosa operated starting from proto-historical times. Fro the dumps and dressing plants tailings of this mine, abundant ore mineral clasts and metal ions have entered the stream and lake sediments. Since an important share of the Lake Medio Flumendosa water is destined to civil uses, interventios aimed at monitoring the metal supply and eliminating water contamination risks are necessary.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
