17.06.120 FILLS — GENERALLY.
   .010   To be Compacted. All fills shall be compacted to meet the requirements of the City Engineer. All lots shall be graded to drain to public or private streets unless otherwise approved by the City Engineer.
   .020   Slope Standards Generally. No fill shall be made with a fill slope steeper than one and one-half horizontal to one vertical and slopes in excess of twenty-five feet in height that are not contour graded shall not be made with a slope steeper than two horizontal to one vertical unless the licensed Engineering Geologist or Soil Engineer in the approved report recommends that a steeper slope would be safer and more stable. Use of contour grading is required in accordance with Council Policy No. 211 and Standards approved by the City Council. Fill slopes in excess of two hundred feet in length shall be contour graded and shall have a variety of slope ratios.
   .030   When Surface to be Flatter. The City Engineer shall require additional engineering information from the Soils Engineer if, in his opinion, a flatter surface is necessary for stability and safety.
   .040   Location on Lot. In the grading of subdivisions or similar developments, the entire area of fill slope shall be confined within one lot or parcel and the top of the fill slopes shall be located as shown in Table No. 17-A, Setbacks.
   In the grading of exterior lots of subdivisions or similar developments and in grading of all single lots, the toe of the fill shall be located as shown in Table No. 17-A, Setbacks.
   .050   General Requirements. Fills shall be compacted, inspected and tested in accordance with, but not limited to, the following provisions:
   .0501   Prior to placing fills, the City Engineer shall require that certificates signed by a Soil Engineer be filed with the City Engineer stating that the subsoils have sufficient stability to support the proposed fill without settlement that may cause damage to proposed improvements.
   .0502   All existing fills shall be certified by the licensed Soil Engineer before any additional fills are added.
   .0503   The space over which fills are to be made shall first be cleared of all trash, brush, trees, stumps, timber, debris, noncomplying fill or other unsuitable materials as determined by the Soil Engineer and Engineering Geologist.
   .0504   All filling shall be done with good sound earth or soil. No oil cake, macadam or bituminous pavement, concrete, rock, boulders or other unsuitable material not easily broken shall be used in the fill, unless the same is distributed, placed more than two feet below the subgrade and does not exceed six inches in the greatest dimension. No "nesting" of such material will be permitted.
   .0505   When an existing fill is to be widened or a new fill is to be made, the new material shall be bonded to the old by plowing deep longitudinal furrows or other method approved by the City Engineer.
   .0506   When an existing fill is to be widened or a new fill is to be made and the slope of the existing fill or the slope of the natural ground exceeds five feet horizontal to one foot vertical, the surface of the existing fill or natural ground shall be cut in a series of benches. Each bench shall be the width of the proposed compaction equipment plus five feet or a minimum width of ten feet and graded to slope toward the cut side of the bench, or such other method as may be approved by the City Engineer. A sectional view shall be drawn on the grading plan showing the width, location and gradient of the proposed benches or the complete details of any other proposed method.
   .0507   All exposed fill slopes shall be protected prior to acceptance with planting, as set forth in Section 17.06.130, Landscaping, in order to prevent erosion.
   .0508   All fills shall be compacted to a minimum of ninety percent of maximum density as determined by Moisture-Density Relations of Soils: Tentative Methods of Test — D1557-58T of the ASTM. Field density shall be determined in accordance with In-Place Density of Soils: Tentative Methods of Test — D1556-58T of the ASTM or equivalent as approved by the City Engineer.
   .0509   A written report of the compaction attained in fill showing the location and depth of test holes, materials used, moisture condition and relative dry density obtained from all tests prepared by a Soil Engineer shall be submitted in duplicate to the City Engineer.
   If the fill is to support buildings or structures, the report shall include recommendations as to the recommended allowable soil-bearing pressures.
   .060   Toeing Out. Fills "toeing out" onto existing slopes which are steeper than two horizontal to one vertical will not be permitted without the installation of protective supports approved by the City Engineer.
   .070   Terracing. Fill slopes exceeding thirty feet in vertical height shall be terraced at approximately mid-height or at maximum intervals of thirty feet. Terraces shall be at least six feet wide except that a minimum eighteen foot wide terrace shall be required at least each sixty foot interval for the height of the fill slope. Terraces shall be paved not less than six feet wide with a minimum longitudinal grade of five percent with minimum three-inch thick reinforced concrete or air-blown mortar in medium or dark earthen tones (black, tan, sienna, umber, ocher, or green) and shall carry water to a safe disposal area as approved by the City Engineer. (Refer to Table No. 17 - A, Setbacks as revised on May 9, 1991).
   .080   Applicability of Section. This section applies to all hillside area fills regardless of whether a grading plan is required by this chapter, except that the tests and reports specified by this section may not be necessary in connection with fills for which no grading plan is required. (Ord. 3411 § 2 (part); April 1, 1975; Ord. 5242 § 2; July 16, 1991.)