406 SE EVERETT MALL WAY BASE FILE 2018-01-02 MF Import

Auto Mall Associates E-2976 May 16, 1986 Page 9 stripped materials should not be mixed with any materials to be used as structural fill. Structural fill is defined as ary fill placed under buildings, roadways, slabs, pavements, or an7 other load bearing areas. Following the stripping operation, the ground surface where structural fill, foundations, or slabs are to be placed should be proofrolled. All proofrolling should be performed under the observation of a representative of Earth Consultants, Inc. Soil in any loose or soft areas should be removed and replaced with structural fill to a depth that will provide a stable base beneath the general structural fill. Structural fill under floor slabs and footings should be placed in horizontal lifts and compacted to a minimum 95 percent of the maximum dry density in accordance with ASTM Test Designa- tion D-1557-78 (Modified Proctor). The £ili materials should be placed at or near the optimum moisture content. Fill under pavements and walks should also be placed in horizontal lifts and compacted to 90 percent of maximum density except for the top twelve (12) inches which should be compacted to 95 percent of maximum density. On -site soils at the time of our exploration were near or above the optimum moisture content and may be used as structural fill provided the grading operations are conducted during dry weather and the soil is near the optimum moisture. However, the on -site soils have a significant amount of fines. Thus, compaction and grading will be difficult if the soil moisture is above the optimum moisture content. Ideally, structural fill which is to be placed in wet weather should consist of a granular material with a maximum size of three inches and no more than 5 percent fines parsing the No. 200 sieve. During dry weather, any compactible non-crgani.c soil can be used as structural fill. FIELD EXPLORATION AND LABORATORY TESTING Our field exploration was performed on April 28, 1986. The subsurface conditions were explored by excavating eight test pits to a maximum depth of nine and one-half feet below the existing surface at the approximate locations shown on Plate 2. Existing facilities along the west margin of the site limited access for the excavation of test pits. The locations of the test pits were approximately determined by tape measurements. Elevations of test pits were approximately determined by interpolation between plan contours. The locations and elevations of the test pits should be considered accurate only to the degree implied by the method used. Earth Consultants, !nc.