(A) General. Unless otherwise recommended in a soils engineering and/or engineering geology report submitted by a professional deemed qualified by the city, fills shall conform to the provisions of this section. In the absence of the report, these provisions may be waived by the city for minor fills not intended to support structures.
(B) Clearing area to be filled. All timbers, logs, trees, brush and rubbish shall be removed from the site. No burning of the debris will be allowed unless a burning permit is issued by the city.
(C) Preparation of ground. The ground surface shall be prepared to receive fill by removing vegetation, non-complying fill, topsoil and other unsuitable material, scarifying to provide a bond with the new fill and, where slopes are steeper than 5 to 1 and the height is greater than 5 feet, by benching into sound bedrock or other competent material as determined by the soils engineer. The bench under the toe of a fill on a slope steeper than 5 to 1 shall be at least 10 feet wide. The area beyond the toe of fill shall be sloped for sheet overflow or a paved drain shall be provided. When fill is to be placed over a cut, the bench under the toe of fill shall be at least 10 feet wide but the cut shall be made before placing the fill and accepted by the soils engineer or engineering geologist, or both, as a suitable foundation for fill.
(D) Fill material.
(1) Organic material shall not be permitted in building pad or roadway areas. Except as permitted by the city, no rock or similar irreducible material with a maximum dimension greater than 12 inches shall be buried or placed in fills.
(2) Exceptions. The city may permit placement of larger rock when the soils engineer properly devises a method of placement, continuously inspects its placement and approves the fill stability. The following conditions shall also apply:
(a) Prior to issuance of the permit, potential rock disposal areas shall be delineated on the plan.
(b) Rock sizes greater than 12 inches in maximum dimension shall be 10 feet or more below grade, measured vertically.
(c) Rocks shall be placed so as assure filling of all voids with fines.
(E) Compaction. All fills shall be compacted to a minimum 90% of maximum density as determined by the Specified Density Method. In-place density shall be determined in accordance with ASTM D698-70.
(F) Slope. The slope of fill surfaces shall be no steeper than is safe for the intended use, or 3 horizontal units to 1 vertical unit, whichever is less.
(G) Grading and terracing. Grading and terracing shall be provided and the area above fill slopes and the surfaces of terraces shall be graded and paved as required by this section.
(Prior Code, § 4.06)