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calibrated flow rates and outflows were measured using tipping bucket rain gauges. A data logger collected
all the instrument data from where it was transferred to a computer. This paper describes the grain size,
saturated hydraulic conductivity and unsaturated flow parameters of the heap leach materials as well as the
column experimental set-up and results. The observed results are discussed as they relate to the flux
application rate, drain down and relative values of water content and matric suction. The results of this
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Hydrology of Rock Dumps
Rock Dumps 2008, Perth, Australia 205
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206 Rock Dumps 2008, Perth, Australia