Geotechnical investigations are made to determine those geologic, seismologic, and soilsconditions that affect the safety, cost effectiveness, design, and execution of a proposed engineering project. Because insufficient geotechnical investigations, faulty interpretation of results, or failure to portray results in a clearly understandable manner may contribute to costly construction changes, postconstruction remedial work, and even failure of a structure, geotechnical investigations and subsequent reports are an essential part of all civil engineering and design projects.