4801 HARBOR LN 2018-01-02 MF Import

Geotechnrcal Engineering ( ort Johnson Residence Addition Everett, Washington J-I280 27 February 2002 Page 3 feet. Below 13 ft.et to the total depth drilled of 21.5 feet medium dense to very dense, wet to saturated, light brown, fine to medium sand with trace to some silt and trace gravel was encountered. Hand auger exploration HA-1 was excavated beneath the existing deck on the eastern side of the residence, approximately 3 feet out from the dwelling. The exploration disclosed approximately 3 inches of 3/8-inch minus crushed rock at the surface over loose, '.amp, brown, silty sand to approximately 2 feet. Below the silty sand, medium dense, damp, brown, medium to coarse gravel was encountered and extended to approximately 2.5 feet. Below the gravel layer loose, damp, light -brown, silty sand with occasional gravel and fine rootlets was encountered to a depth of approximately 4 feet. Below the silt-i sand to the total depth explored of 5 feet, dense, moist, light brows; and gray, silty sand to sandy silt with occasional gravel was encountered. The Distribution and Description of Geologic Units, Mukilteo Quadrangle, Washington (U.S.G.S. Map MF-1438, 1982) describes the site as near a contact between glacial till and advance outwash deposits. Subsurface conditions as disclosed by the explorations completed for this study are consistent with the published mapping data in that the native granular soils encountered below the fill material consist of advance outwash deposits - glacially consolidated sand with some gravelly and silty horizons. Groundwater Groundwater was encountered in boring B-lat the time of our field exploration at a depth of approximately 20 feet. Groundwater was not observed in the hand auger boring. It should be noted that groundwater conditions are likely to fluctuate due to seasonal precipitation variation, site utilization, irrigation, and other factors. CONCLUSIONS AND RECOMMENDATIONS Site improvements for the Johnson property include the following elements: • Construction of a two-story addition to the north end of the dwelling; • The dwelling addition is expected to have foundation loads on the order of 3 kips per lineal foot, based upon information provided to us by Fred Baxter & Associates; • At the time this report was written, the decision had yet to made whether the addition would employ a slab -on -grade lower level floor or a crawlspace; • Removal of the existing deck that extends from the north and east sides of the dwelling, and construction of a new deck with a larger footprint; • Site grade changes are not anticipated, although foundation construction activity will require excavation activity that may result in final grade changes. Ziooer Zeman Associates. Inc. 18905 33r° Avenue West, Suite 117 L)nnwood, Washington 98036 (423) 771 -3304