Seismic refraction profile across a proposed building site. Since the building excavation and site grading required deep cuts, the survey purpose was to map the depths and rippabilities of subsurface materials. Based on a ground truth test pit (C-1), the layering was interpreted as light dry topsoil over residual silty clay over weathered phyllite bedrock. Comparison of the measured layer velocities with standard ripping charts indicated that the proposed excavation and grading could be completed without blasting.