This excavator is removing C-slag from the FC furnace granulation pit. Unlike the S-slag which is tapped into large Kress pots, cooled, ground and reprocessed due to remaining 2% copper content, C-slag has only a minuscule amount of copper so, like matte, it is tapped and fed into a turbulent granulation water pit and then removed by this excavator for use as a furnace coolant (among other things) to regulate furnace temperatures and chemistry.