Index statistic on deep borehole prospecting test and verification of various in situtests in Lixigo uindicate that deep part survey index of high tailing dam is greater than shallow part.Under the circumstance of the same spatial location and the same depth of piling dam body

gravity index increases significantly with time.Physical indexes are selected by the early

middle

and late stages in the stability analysis of high tailing dam for the same material(medium sand silt).Improved drainage structure method is adopted to simulate densely dist ributed drainage holes.By using complex three dimensio nal seepage soft ware(SP GCR 3.FOR)

the inverse analysis of sat uration line and seepage discharge is made for a status dam of a height of 135 m.According to the fitting inverse analysis of drainage and seepage facilities

the mat hematical model which conforms to the reality is obtained.The outcome from the analysis mentioned above coincides with the groundwater level in t he survey section and observed seepage discharge

with the error less than 13%.Accordingly

the seepage model and stack pile sedimentary seepage parameter are found

which can be applied to the analysis of dam heightening in late stage.It also demonst rates that radial wells can lower saturate line obviously.