Laserfiche WebLink
April 1, 2019 <br />ES-6516 <br />DevCo, Inc. <br />10900 Northeast 8t" Street, Suite 1200 <br />Bellevue, Washington 98004 <br />Attention: Mr. David Ratliff <br />Dear Mr. Ratliff: <br />Earth <br />Solutions <br />NW«C <br />Earth Solutions NW LLC <br />Geotechnical Engineering, Construction <br />Observation/Testing and Environmental Services <br />Earth Solutions NW, LLC (ESNW) is pleased to present this report titled "Geotechnical <br />Engineering Study, Four Corners, 8102 Evergreen Way, Everett, Washington". Based on the <br />results of our investigation, the proposal is feasible from a geotechnical standpoint. Our study <br />indicates the site is underlain primarily by glacial till, with minor areas of fill. Perched groundwater <br />seepage was encountered at the boring locations between depths of about 3 to 15 feet below the <br />existing ground surface elevation. In our opinion, the contractor should be prepared to manage <br />discrete zones of groundwater seepage during construction. <br />Based on our findings, it is our opinion the proposed multi -family structures may be constructed <br />on conventional continuous and spread footing foundations bearing upon dense to very dense <br />native soil. In general, dense native soil suitable for support of foundations will likely be <br />encountered beginning at depths of about two -and -one-half to eight feet below existing grades. <br />Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations, <br />overexcavation to a depth that exposes dense native soils and replacement with crushed rock or <br />lean mix will be necessary. <br />Given the presence of dense to very dense native glacial till at relatively shallow depths, it is our <br />opinion infiltration is not feasible from a geotechnical standpoint. The appreciable fines contents <br />and high in -situ density of the deposit will likely inhibit the function of any full-scale infiltration <br />system. From a geotechnical standpoint, the native glacial till should be considered impervious <br />for purposes of large scale infiltration design. <br />Pertinent geotechnical recommendations are provided in this study. We appreciate the <br />opportunity to be of service to you on this project. If you have questions regarding the content of <br />this geotechnical engineering study, please call. <br />Sincerely, <br />EARTH SOLUTIO S INW, LLC <br />R <br />a,.._ �- <br />CNase G. Halsen <br />Senior Staff Geologist <br />1805 - 136th Place N.E., Suite 201 • Bellevue, VVA 98005 0 (425) 449-4704 4 FAX (425) 449-4711 <br />