Recharge in Rehabilitated Opencast Collieries
Groundwater levels and pumping records from five rehabilitated opencast pits at South African collieries, for hydrogeologists and closure planners estimating post-mining water balances.
Recharge factors of 23.5 per cent and 12.9 per cent were calculated at the two rehabilitated pits with complete data. The higher value reflected surface drainage towards the pit centre and eroded topsoil; the lower one, a deep pit floor with well compacted spoil and intact cover. The rates are site specific and no generic formula could be derived.
R1500,00
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