Every grading permit shall expire and become null and void if the work authorized by such permit has not been commenced within 60 days of the time shown on the construction schedule, or at such time that a revised construction schedule indicates that an erosion and sedimentation control permit is required pursuant to
§ 15.28.070; except that the Engineer may, if the permit holder presents satisfactory evidence that unusual difficulties have prevented work from being started or completed within the specified time limits, grant a reasonable extension of time on said permit; provided that the application for the extension of time is made before the date of expiration of the permit and an erosion and sedimentation control permit is obtained when required.
(`83 Code, § 15.28.100) (Ord. 85-11 § 1 (part), 1985)