The Ajka alumina sludge spill was an industrial accident at a caustic waste reservoir chain of the Ajkai Timföldgyár alumina plant in Ajka, Veszprém County, in western Hungary. On 4 October 2010, at 12:25 CEST (10:25 UTC), the northwestern corner of the dam of reservoir no. 10 collapsed, freeing approximately one million cubic metres (35 million cubic feet) of liquid waste from red mud lakes. The mud was released as a 1–2 m (3–7 ft) wave, flooding several nearby localities, including the village of Kolontár and the town of Devecser. Ten people died, and 150 people were injured. About 40 square kilometres (15 sq mi) of land were initially affected.