1810 104TH ST SE A T AND T WIRELESS ANTENNA 2022-12-02

Geotechnical Engineering .:apart Irerracon SN4924—Silver Lake North Cell Tower Everett,Washington October 24, 2014 Terracon Project No. 81145043 4.3.4 Construction Considerations The base of all foundation excavations should be free of water and loose or soft soil or loose rock prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing material disturbance. If the material at bearing level becomes excessively dry, disturbed, saturated, or frozen, the affected soil should be removed prior to placing concrete. If unsuitable bearing soils are encountered in footing excavations, the excavations should be extended deeper to suitable soils and the footings could bear directly on this soil. Overexcavation for compacted structural fill placement below footings for support equipment should extend laterally beyond all edges of the footings at least 8 inches per foot of overexcavation depth below footing base elevation. The overexcavation should then be backfilled up to the footing base elevation with Select structural fill placed and compacted as specified in Compaction Requirements of this report. The overexcavation and backfill procedure is described in the following figure. Design 213D 11, w 213D Footing Level _—..-. - COMPACTED STRUCTURAL N FILL OTE:Excavation n sketch shown vertical for convenience. Recommended Excavations shoul be sloped as necessary for safety. Excavation Level 1L 41 Overexcavation / Backfill 4.4 Equipment Shelter and Generator Slabs The equipment shelter and generator slabs may be supported on 4 inches of structural fill prepared per the Site Preparation and Subgrade Preparation sections of this report. To provide a capillary break, the structural fill should consist of clean, free-draining, uniformly graded gravel, containing less than 5 percent fines, based on that soil fraction passing the US No. 4 sieve. Responsive■ Resourceful■ Reliable 9