The costs to treat a large landslide are dictated by geometry, site considerations, and the methods that are used to improve the balance of forces within the landslide. Potential methods can involve drainage, earthwork and structures. Drainage techniques often include trenching, relief wells and horizontal drains. Earthwork techniques may include unloading, buttresses and key trenches. Structural techniques for large slides are typically large diameter piles with tieback anchors. A phased approach would determine which technique is appropriate for any given landslide.
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