An average of 69.5 Ml/d of acid mine drainage water was treated and the water level in the basin was 115 m below Environmental Critical Level, having increased by 0.1 m since the pumping commenced in September 2016 and was still 15 m below the Environmental Critical Level. The aim is to maintain the water level 20 m below Environmental Critical Level in order to provide a buffer.

The environmental specifications for release of the treated water into the river system were consistently met
throughout the year.