A system of mining which does not use shafts or tunnels and is, hence, cheaper. The layer above the mineral seam is removed and the exposed deposit is extracted using earth-moving machinery. The overburden may then be replaced. See Ghose and Majee (2001) J. Env. Manage. 63, 2,193 on air pollution caused by opencast mining and its abatement measures in India, and the 1980 edition of the New Zealand Geographer 36, 2, 85 on potential environmental impacts of opencast mining.