The Acid Mine Water Drainage Scheme is a project to de-water abandoned gold mines in the Johannesburg Area. Since the mid-19th century, gold mines started moving and followed the gold vein. Many of the original mine shafts near Grootvlei became abandoned and over the years filled with acidic mine water. Persistent rain and raising groundwater caused steadily raising water levels in tunnels and shafts. This has serious implications for the Johannesburg area, be-cause the water contains dissolved heavy metals and sulphur. On an earlier phase of the scheme peristaltic pumps were installed for lime slurry dosing which is used to neutralize the acidic water. However, these pumps were expen-sive to maintain and had a high power consumption.