PROCEDURES FOR ASSESSING FLOW CAPACITY AND SEEPAGE FACE PATTERNS OF LINEAR DEPOSITS OF MINE WASTE
CIM Montreal 2011
Ali Roshanfekr, David Hansen,
Linear mine-waste dumps at open-pit mine sites essentially represent expedient places to deposit
large quantities of waste rock. In order to provide better tools to assess the behaviour of these
dumps, a systematic study was conducted at Dalhousie University. Firstly, physical models were
built to assess the flow capacity and hydraulics associated with the linear growth of such dumps.
It was found that the elevation of the point-of-first-emergence on the downstream side becomes
constant after the dump grows to a certain length, but that the upstream depth concurrently
increases. The applicability of the theories of Hansen et al. (1995, 2005) in this regard are
discussed. Secondly, in studying the seepage face downstream, two approaches for solving the
Spatially Varied Flow (SVF) algorithm were undertaken. Under one of the approaches, flux
nodes were used to link the SVF algorithm to the hydraulic heads ‘inside’ the embankment.
Under the other approach this linkage was made directly to the hydraulic heads of the
embankment. These two methods could be made to perform equally well. It is suggested that a
near-linear variation in depth can be used instead of the complex SVF algorithm and the results
using this near-linear variation are presented and verified.
Linear Waste Rock Dumps, Effective Hydraulic Gradient, Hydraulic Behaviour, Mine Waste Deposits, Seepage Face, Spatially Varied Flow