An average of 62 Ml/d of acid mine drainage water was treated and the water level in the basin was maintained at 113 m below the ground level, having dropped 10 m during the year, but still 13 m above the Environmental Critical Level at 126 m below ground level.

The initial environmental specifications for release of the treated water into the river system were generally met
except for some initial incidents where the turbidity and sulphates parameters were exceeded. The specifications
were subsequently modified by DWS, which resulted in consistent achievement of the discharge requirements
throughout the year.