Zandfontein UG2 TSF
The tailings have been deposited in the TSF from 1980 until 2013, when the mine went on Care and Maintenance. The material in the TSF was primarily derived from the processing of UG2 Chromitite ore. The tailings deposited in the TSF, originated as fines after milling and extracting the PGEs concentrates. Therefore the Cr2O3, PGEs and Au mineralisation that is now being targeted in the tailings, originates from within the UG2 chromitite seam itself. Some of the tailings were later reprocessed at Barplats to extract a limited amount of the Cr2O3 (an estimated at 1%-2% was processed) and PGEs (estimated at a grade of 0.2 g/t) and then re-deposited in the new front compartment of the tailings dam (Figure 9). The tailings also contain silicate material and minor amounts of base sulphide minerals or their oxidized products.

The average Cr2O3 and FeO contents (derived from 246 tailings samples) for the the Project are; 20.72% and 15.65% respectively. The average of Cr to Fe ratio on the TSF in Domain 101 is 1.35 and in Domain 102 1.28. The chromium oxide present in the tailings is in the form of chromite grains that have been liberated during the crushing and milling of the chromitite ore. The Au is expected to be present as very fine grained particles that were released after the oxidation of the primary sulphide minerals. It is assumed that the major silicate minerals present are pyroxene (enstatite/bronzite composition) and plagioclase feldspa ........

Barplats’ preference is not to establish a new TSF (Tailing Storage Facility) and so the strategy is for the tailings from the plant to be placed back onto the footprint of the existing TSF while it is being exploited. The TSF has been divided into six areas as part of a strategy to exploit the total volume of tailings material.

Hydraulic mining and Mechanical loading of material on the north-western section will start simultaneously. The associated tailings from the plant following processing will be re- deposited using the cyclone method.

Mechanical loading is necessary in the coarse area of the TSF where material is chemically bonded in layers, which is not able to be hydraulically broken down to the minus 3mm fraction, which is the maximum plant feed size.

Mining Methodology.
Modelling was used to determine the most suitable technique for mining the TSF. The methodology involves continual and simultaneous cleaning, construction, hydraulic mining and deposition activities.

Certain areas need to be excavated using mechanised equipment (i.e. coarser harder material) while other sections of the TSF can be mined hydraulically (i.e. finer softer material).

Mechanised Operations.
Coarse material will be excavated, using a dry mechanised mining method.

The mechanically mined material will be trucked to a scalping screen, which will dry screen the vegetation from the material, after which it will pass thro ........

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