Whose "Fault" Is It? – Engineering Geologic Support for Litigation

Elizabeth Lincoln Mathieson
Exponent Failure Analysis Associates, Oakland, CA

When construction projects fail to meet consumers’ performance expectations, lawsuits are often filed. Engineering geologists are among the professionals retained to investigate the causes of damage. Performance problems related to site geology range from spectacular slope failures to subtle manifestations of the interaction between structures and the underlying soil.

Certain homebuyers seek out dramatic settings for their dream homes and are taken aback when the drama of the setting suddenly comes to include crumbling ground beneath their houses. Even in less spectacular landscapes, slopes evolve through time, and the buyer of a hillside structure counts on the developer’s engineers to have halted all natural processes of slope evolution. Despite technological advances in monitoring devices, the most sensitive monitors of fill settlement and slope deformation may be the human occupants of structures built on fills and slopes. Some of these occupants retain attorneys to seek compensation for building performance that does not meet their expectations.

Engineering geologic investigations of failures and alleged failures rely on conventional geologic skills and an understanding of the significance of various geologic conditions and processes on the design, construction, and behavior of engineered structures. Important geologic skills include recognition of landforms indicative of past ground movement, interpretation of subsurface materials and geometries based on environments of deposition, and 3D visualization of subsurface conditions. In performing field inspections of man-made structures and their surroundings, the engineering geologist can adapt conventional techniques of geologic mapping and interpretation to the documentation and analysis of structural distress. These techniques are invaluable in investigating the causes of damage in matters ranging from backyard landslides to multi-million-dollar construction lawsuits, all with the objective of allocating responsibility, or "fault."