11229 19TH AVE SE SILVER LAKE TOWNHOMES WHOLE SITE Geotech Report 2022-10-25

Geotechnical Report Proposed Development: 11229 - 1 9th Avenue SE, Everett, WA September 16, 2016 As it is not possible to observe the completed pile below the ground, judgment and experience must be used as the basis for determining the acceptability of a pile. Therefore, all piles should be installed under the full-time observation of a representative of PanGEO. This will allow us to fully evaluate the contractor's operation, collect and interpret the installation data, and verify bearing stratum elevations. Furthermore, we will also understand the implications of variations from normal procedures with respect to the design criteria. The contractor's equipment and procedures should be reviewed by PanGEO before the start of construction. 5.3 FLOORS SLABS The floor slabs for the proposed buildings may be constructed using conventional concrete slab- on-grade floor construction. The floor slab should be supported on competent native soil or on structural fill. If conventional footing option is used for Building E,the concrete slabs for Building E should be supported on a minimum of 12 inches of structural fill. Interior concrete slab-on-grade floors should be underlain by a capillary break consisting of at least of 4 inches of pea gravel or compacted 3/4-inch, clean crushed rock(less than 3 percent fines). The capillary break material should meet the gradational requirements provided in Table 3, below. Table 3 —Capillary Break Gradation Sieve Size Percent Passing 3/4-inch 100 No. 4 0— 10 _ No. 100 0—5 No. 200 0—3 The capillary break should be placed on the subgrade that has been compacted to a dense and unyielding condition. A 10-mil polyethylene vapor barrier should also be placed directly below the slab. Construction joints should be incorporated into the floor slab to control cracking. 16-210 11229 19th Ave SE Rpt Page 10 PanGEO, Inc.