Whenever a possible slippage plane is apparent on the surface or encountered during the excavation work, a written report shall be furnished the City Engineer by the Engineering Geologist prior to any further work being performed within the area affected by said slippage plane. Said report shall include recommendations for the remedial treatment required to prevent potential hazard to the area caused by the slippage plane. Permittee shall take such protective measures as shall be required by the City Engineer in order to safeguard the area against the said potential hazard. (Ord. 3411 § 2 (part); April 1, 1975.)