The phenomena of flowing sands and water exit at high positions on the downstream slope of a tailings filled dam were focused in the seepage and stability analysis of the tailing dams to propose a safety evaluation of its seepage and stability

and strengthening measures in this paper.The safety evaluation included: a field surveying of the topography of the tailing dams and its neighboring area with an advanced 3D laser scanner to provide basic data for numerical computation;an indoor laboratory testing of samples from the tailing dams consists of grain distribution

permeability

and shear strength tests;a back-analysis based on the heights of water exit position to get proper anisotropic values of hydraulic seepage in tailings and vertical flux on the top of the dam;a series of seepage and stability analyses for six cases of dam heights accounting the current state and the future plans of the tailing dams indicate that the dam was under a critical state of sliding failure

and the radiation wells should be implemented as precipitation measures to strengthen the tailing dams.After adoption of the strengthening measures

the safety factor has been increased over 1.7 so that the phenomena of water exit at high positions and piping on the downstream of the dam have been eliminated.