Abstract: The 5.12 Wenchaun earthquake resulted numerous geohazards such as soil and rock slides. Under the influence of heavy precipitation and aftershocks, the probability of slides in the slopes increases significantly and it is necessary to mitigate the hazard to ensure the safety of life and properties. This paper presents a case history of the mitigation of an unstable slope in Qingchuan County. The stability of the of the slope was analyzed through numerical simulation in accordance with the current code requirements. The results indicate that, under the strong precipitation and an earthquake magnitude of 7.0, the factor of safety of the slope is 1.07, which is marginally stable. The site visual inspection indicates that there are loose rocks accumulated on the slope due to the earthquake. These rocks are the potential safety hazards to the public since they could be fell down due to the rain or seismic actions. The mitigation measures include the removal of loosen rock, active and passive rock nets.

Key words: Unstable Slopes, Numerical Analysis, Stability Analysis, Emergency Response for Stabilization