I am often called to provide a Structural Engineering assessment and consultation and evaluation in Laguna Niguel. Often times the cause of foundation settlement is both global slope creep and local soil saturation. Sometimes even though there is a hillside slope and houses are vulnerable to future movement, slope creep has only occurred at negligible amounts. Sometimes there are multiple directions for slope creep if there are hillsides on the different sides of the house. The only way to know if a retrofit is required is to understand the nature of the movement with respect to the configuration of the house framing and the vulnerability to further slope creep.
Jeremy