No person shall excavate on land sufficiently close to the property line to endanger any adjoining public street, sidewalk, alley or other property without supporting and protecting such public street, sidewalk, alley or other property from settling, cracking or other damage which might result from such excavation. Should the nature of the excavation create a potential hazard to life unless adequately fenced, the applicant may be required to construct approved fences or guardrails to safeguard persons using the public street, sidewalk, alley or other property. (Ord. 3411 § 2 (part); April 1, 1975.)