Characterization of amalgamation tailings from ASGM in Sekotong area, West Nusa Tenggara, Indonesia, and its potential added value

Abstract

Artisanal and small-scale gold mining (ASGM) in Indonesia still uses mercury in amalgamation process to extract gold form the ores. The process easily produces gold but at the same time produces very dangerous mercury waste. In this study, a comprehensive series of tests were carried out on amalgamation tailings from the ASGM in Sekotong area, West Nusa Tenggara. The tailings contain mercury up to 150 ppm, above the safe threshold, and gold up to 20 ppm which is intended to be recovered. Furthermore, mineral liberation analysis (MLA) and gravity recoverable gold (GRG) test were performed to determine the feasibility of recovering gold from the tailings. The liberation degree of the gold started from particle size of 37 \xm causes challenging to recover it. However, the GRG test confirmed that the gold was still feasible to be recovered by gravity concentration.

Mercury content in mining waste and its effect on the surrounding environment (Case study: Small-scale gold mining locations-West Sumbawa)

“…Meanwhile, while for mercury in sediment referred to the Canadian sediment quality guidelines for threshold effect level (TEL) and probable effect level (PEL). Rahman and Setiyadi [9] conducted a mercury investigation in Taliwang Lake and shows that there was mercury in water bodies and sediments at concentrations of 1.95 g/L and 291 g/kg, respectively. The presence of mercury in Taliwang Lake contaminated aquatic organisms which were part of the food chain and was harmful to other living things.…”