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C7 6.9.2 Removal and Recompaction . The near -surface soil to a depth of approximately two feet appears to consist partially of old uncompacted fill containing broken asphalt concrete and gravel. In order to provide a uniform and firm base, the upper 24 inches of existing soils below existing grade or finish subgrade, whichever is lower in elevation, should be removed, moisture conditioned and recompacted to the specifications of Section 6.8.3. This removal and recompaction will be required in the areas of proposed structures, such as building and canopy pads, and in all pavement areas. Removal and recompaction should be performed to at least two feet beyond building footing and paving limits unless limited by property line or other constraints. It is imperative that the bottom of the subexcavations be inspected by the Project Soils Engineer. Should any artificial fill be encountered within the exposed bottom of the subexcavations, the depth of removal and recompaction should be extended uniformly in the entire area of the building and pavement, in order to prevent intolerable differential settlements. 6.9.3 Placement of Compacted Fill Guide specifications for placement of fill and backfill are provided in Appendix C. The bottom of subexcavations and areas to receive fill should be scarified to a depth of 6 inches, then moisture conditioned to near -optimum moisture content and surface compacted to the relative compaction specified below. It should be noted -that at the time the field exploration for this investigation was performed, the native soil encountered just below the asphalt and gravel fill was, in general, at approximately optimum moisture content while the soils encountered at and below a depth of approximately five feet were seven to ten percent above optimum moisture content. If these moisture conditions exist at the time of construction, special grading procedures may be necessary in order to perform the recommended grading without causing "pumping" and/or rutting of the underlying soils. At this time, we don't anticipate the stabilization of the excavation bottom with a layer of gravel and/or geofabric will be necessary; however, change in site conditions may require such stabilization. Placement of compacted fill should be performed in thin lifts at slightly above optimum moisture content (approximately 2 percent), using mechanical compaction equipment. Unless specified otherwise, all fill should be compacted to a minimum of 90 percent relative compaction based upon the maximum density obtained in accordance with ASTM Standard D 1557. During grading, frequent density testing should be performed by a representative of the geotechnical engineer to evaluate compliance with grading specifications. Where testing indicates insufficient relative compaction, additional compactive effort should be applied, with the adjustment of moisture content where necessary, until the required relative compaction is obtained. na 4OW7-095-01 m87-06j-Iaun-.d- 6-7