Of or pertaining to strip mining, in which material is removed from a surface that has been exposed(adjective)
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Use "opencast" in a sentence
"Sinosteel, another Chinese-owned metals conglomerate, has plans to develop a massive opencast iron ore mine in the Weld range, a ridge of hills 400 miles north-east of Perth."
"Under the plans, ministers agreed to keep a permanent stockpile of at least six months 'supply of coal, increase coal imports, build more oil-burn, nuclear and gas-fired power stations and encourage development of more opencast mines."
"The only other working goldmine in the UK is in County Tyrone, Northern Ireland, an opencast site near Cavanacaw which uses the same strata of rock at Cononish."