3632 RUCKER AVE THE LANDING AT PORT GARDNER Geotech Report 2023-04-10

GE0TECH 240110th Ave E 2 CONSULTANTS, INC. S18 FAX X(4i 5)7 -98161 (425)747-5618 FAX(425)747-8561 JN 18188 April 16, 2018 MTT Construction LLC 16000 Christensen Road #150 Seattle, Washington 98188 Attention: Kjell Lindberg via email: kjell@mttholdings.com Subject: Geotechnical Engineering Report Proposed Apartment Building 3650 Rucker Avenue Everett, Washington Dear Mr. Lindberg: Our firm prepared a geotechnical engineering study for a proposed apartment building project dated February 16, 1999. The project proposed in 1999 was never constructed. We understand that a new apartment building project is now proposed for the site. This new project is similar to one proposed in 1999. This report provides an update to our 1999 study. The subject property was vacant when four test pits were excavated on the site in preparation for our 1999 study. We made a recent site visit and confirmed that conditions on the site are currently extremely similar to the site.conditions in 1999. Thus, the soil conditions revealed in the 1999 test pits are still very valid today. The soils revealed in the test pits consisted of dense to very dense, very competent, glacial till soil at depths of approximately 3.5 to 5 feet. Loose to medium-dense fill and native soils were revealed overlying the competent soil. Project plans were recently received indicate that the lowest, parking level of the building will be at approximately elevation 181 feet. This level will be buried about 10 feet below the ground on its southern side, but will daylight to the north and northeast. If this scope of the project changes from what we have described above, we should be provided with revised plans in order to determine if modifications to the recommendations and conclusions of this report are warranted. CONCLUSIONS It is our professional opinion that, the with the one exception of some seismic updates noted below, our 1999 study is still adequate and applicable to the newly proposed apartment building project. The soil parameters provided in the study are applicable. Conventional footings are suitable for the proposed building provided they bear on the very competent glacial till soil. Some relatively minor overexcavations may be needed on the daylight side of the lower parking level in order to reach the competent soil. In accordance with the International Building Code (IBC), the site class within 100 feet of the ground surface is best represented by Site Class Type C (Very Dense Soil). As noted in the USGS website, the mapped spectral acceleration value for a 0.2 second (Ss) and 1.0 second period (S1) equals 1.34g and 0.51g, respectively. The SBC and ASCE 7 require that the potential for