Geotechnical data reports including boring logs and in-situ and lab testing will be used in collaboration to assign design parameters to stratigraphic units. As previously mentioned, SPT provides an acceptable means to gage strength of sands, but hits refusal in bedrock and Intermediate Geomaterial (IGM) and results are highly variable in cohesive material. Lab results (in accordance with Chapter 4) are essential to isolate compressive and shear strength parameters when in clay or rock.