24. An engineered landfill may also be sited in a rock quarry or a mine so long as(1) the quarry or mine is an open pit;
(2) the quarry or mine floor is situated below the groundwater level; and
(3) the average groundwater infiltration rate, calculated on an annual basis, is 5 x 10-4 m3 or less of water per square metre of quarry or mine wall situated below the groundwater level.