The objective of a geotechnical investigation is to characterize the geologic environment. This may include;
1) The lateral distribution and thickness of the soil and rock strata.
2) Groundwater Conditions and quality.
3) Ground response to changing conditions such as surface loading from structures and unloading by excavations or extraction.
4) Physical properties of soils and rock formations.
5) Engineering properties of soils and rock formations.
6) Hazardous conditions such as unstable slopes, faults, flood plains, ground subsidence and heave potential.
The magnitude of the site investigation depends upon the geological variability of the site as well as the size (spatially and financially) of the planned project.