Abstract
The Olympias old TMF is located 2 km NW of the Olympias village, in the vicinity of the old Olympias mill. It was constructed back in 1976 when the Olympias mine was first put in production and operated till 1995 for the deposition of the tailings from the Olympias ore beneficiation. 2.4 Mt of tailings were deposited containing S: 6,0%, Fe: 6,0%, As: 1,9%, and Au: 3,4 g/t occupying an area of 300 acres. Another 1.6 Mt of contaminated soils was found underneath the old TMF that needs to be removed.
Within the framework of the Kassandra mines development by Hellas Gold S.A., a subsidiary of Eldorado Gold Corporation, the company proceeded with the cleaning and restoration of the Olympias old TMF in an effort to combine the practical demonstration of "cleaning and restoration of all non-functional old mining areas in the new design" of the Business Plan, with priority and, the need for maximum environmental upgrading, wherever and whenever possible, within the Kassandra mines project area.
Over the period 2013–2016, the old tailings removed from the TMF by conventional mechanical equipment and hauled to the existing adjacent flotation plant for the recovery of 340 kt marketable auriferrous AsPy/Py concentrate with 20 g/t Au.
The retreated tailings and the contaminated soils underneath the old deposition were transported to the properly lined Kokkinolakkas TMF for environmentally safe disposal.
In parallel with the removal and cleaning of the old tailings and contaminated soils, gradual rehabilitation of the released area is carried out. Rehabilitation includes restoring the background to convert it into soil suitable for planting and subsequent phytoremediation with native species of the area.
Today, more than 3.1 of the old tailings and contaminated soils have been removed while the whole project is planned to be completed by 2026.
The project contributes to the final and permanent restoration of any impacts created from past mining activity and is reclaimed for the natural and human environment of the immediate and the wider area.