Measurements and model predictions of the rate of drying with time at the surface of a waste-rock pile after heavy rainfall events

• Main Authors: Kabwe, Louis Katele, Wilson, G. W.
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/8856

Measurements and model predictions of changes of water contents at the surfaces of waste-rock piles are needed in the development of a long-term management plan for waste-rock piles. This study investigated a short-term multi-day [July 28 to August 4, 2002] rate of drying with time at the near-surface of the Deilmann north waste-rock pile (DNWR) at the Key Lake uranium mine, northern Saskatchewan, following the cessation of 75.9 mm rainfall over the initial 48-h period. The water content was determined using the gravimetric method. The initial measured water content profile data were used with SoilCover numerical model to predict changes in water content profiles with time at the near-surface of the DNWR. Results of both the measurements and numerical predictions showed that the impact of heavy rainfall events on waste-rock surface water content at the DNWR is of relatively short duration. The waste-rock surface (0 m) water content was very sensitive to changes in climatic conditions after precipitation, exhibiting a power decrease with time. The drying rates at greater depths (>0.05 m) decreased slowly with time. This behavior was attributed to hydraulic properties of the waste-rock pile. These data can be of value in the long-term development of a plan for mine waste management.