Cleaning mercury polluted mine tailings in the Philippines

Appel, P.*; Na-Oy, L.*; Hatsukawa, Yuichi; Osawa, Takahito  ; Kystol, J.*; Srensen, L.*

This report presents the results of experiments involving the revival of an old method for removal of mercury from tailings after gold extraction by small-scale miners. Numerous tailings from small-scale gold mining are found throughout the Philippines. The tailings have proved to contain large amounts of mercury (up to 250 gram per ton). Furthermore, the tailings contain large amounts of gold locked-up in the mercury - up to 16 gram per ton. The mercury occurs as mercury flour (globules less than a millimetre across). Mercury flour is produced through milling of gold ore, when the mercury is added to tailling drums (whole ore amalgamation). The globules "hidden" in the mercury flour cannot be recovered by small-scale gold miners in any environmentally benign ways.