No person shall conduct any grading, clearing, brushing or grubbing on natural or existing grade that is preparatory to grading, without first having obtained a grading permit from the city. Exceptions to this requirement are as follows or as otherwise determined by the city:
A. An excavation below finished grade for basements and footings of a building, mobilehome, retaining wall, or other structure authorized by a valid building permit or construction permit. This shall not exempt any fill made with the material from such excavation nor exempt any excavation having an unsupported height greater than five feet after the completion of such structure. This shall not prohibit a minimum fee grading permit or soil or geologic report from being required for foundation design and inspection purposes when, in the opinion of the city, stability or flooding considerations warrant such inspection;
B. Cemetery graves;
C. Refuse disposal sites controlled by other regulations;
D. Earthwork construction regulated by the federal, state, county or city governments, or by any local agency as defined by Government Code Sections 53090 through 53095 (special districts), pipeline or conduit excavation and backfill conducted by local agencies or public utilities and earthwork construction performed by railway companies on their operating property. This exemption, however, shall apply only when the earthwork construction takes place on the property, or dedicated rights-of-way or easements of the above agencies;
E. Excavation and backfill for installation of underground utilities by public utilities or companies operating under the authority of a franchise or road;
F. Mining, quarrying, excavating, processing, stockpiling of rock, sand, gravel, aggregate or clay where established and provided for by law, provided such operations do not affect the lateral support or increase the stresses in or pressures upon any adjacent or contiguous property;
G. Exploratory excavations under the direction of soil engineers or engineering geologists, provided all excavations are properly backfilled. All such excavations and trenches are subject to the applicable sections of Title 8 of the State Orders, Division of Industrial Safety;
H. An excavation which does not exceed fifty (50) cubic yards on any one site and which: (1) is less than two feet in vertical depth, or (2) which does not create a cut slope greater then five feet in vertical height and steeper than one and one-half horizontal to one vertical (1 1/2:1);
I. A fill less than one foot in depth placed on natural grade with a slope flatter than five horizontal to one vertical (5:1), which does not exceed fifty (50) cubic yards on any one lot and does not obstruct a drainage course. (Ord. 48, 1990)