3611 FEDERAL AVE 2018-01-02 MF Import

Geologic Investigation and Geotechnical F_n¢ineenrig Re ' Jones Residence 3611 Federal: l ve. Everett, Washington 98-08-10 Due to the varying depths of Topsoil remaining across this site, we anticipate that the top elevation of the Transitional Beds (Otb) Silt will vary considerably around the site. Excavation depths for the removal of the remaining Topsoil will range from one (1) to three (3) feet below existing site grades based upon the site investigations. Actual depths excavated at the time of construction may be more than those estimated herein. Topsoil thickness in any one location may result in the removal of materials to below the designed footing elevations. No footings should be founded in or above any Topsoil, undocumented fill, or loose native soil. As mentioned previously in this report, the basal silt is moisture sensitive. The engineering characteristics of the silt will change once it becomes moisture disturbed. Because of this, any moisture disturbed silt will have to be removed from below the footing excavations prior to placement of any concrete. Recommended footing support alternatives are given below - in order of the most to least desirable: 1) Prepare building site as recommended above. Grade and fill building site with structural fill as necessary to meet building elevations. Excavate footing areas to natural soil as confirmed by (E.S, Inc. Proof roll and compact exposed siaiace to a non yielding condition. Replace any yielding soil with 2" to a" crushed rock as oullined above. Place footings directly upon approved, undisturbed natural soil or crushed rock cis directed by GE.S, Inc. Foundations should be placed a minumon 1'" into the approved bearing .coil in order to achieve the maximum hearing support as .specified in this report. 2) Upon the approved subgrade surface, grade crud fill building site with .structural fill to floor grade. Excavate helow.foundation areas through structural fill back clown to rile "Transitional Bed (Otb) Silts and backfll with controlled density fill (CDF) to footing elevations. CDFshotdd extend a minimum six (6) inches beyond the outside ol;joolings tit all directions. Place footings upon CDF or upon natural, undisturbed .coil as approved by GE.S, Inc. 3) Grade and fill building site with 2" minus crushed rock to base of fi�oting elevation. The area between the footing elevation and grade may be filled with approved structural fill. Excavate through structural fill and place footings directly upon crushed rock as obsen ed and approved by GE.S, Inc. 12 GES, Inc.