"Geotechnical engineering" means the application of geologic knowledge and principles in the investigation and evaluation of naturally occurring rock and soil for use in the design of civil works projects. "Geotechnical engineering" also means the application of soils mechanics in the investigation, evaluation and design of civil works involving the use of earth materials and the inspection or testing thereof. (Added by Amended Ord. 02-064, Dec. 9, 2002, Eff date Feb. 1, 2003).