4107 OLIVE ST 2018-01-02 MF Import

J A N- 2 2- 9 3 FRI 1 4: 1 9 I DAVID L. NELSON AND ASSOCIATES, INC. Consulting Enginerring 6coingY October 10, lggo project Ho. %90 pap y saturated silty nand soils that would cause significant risk. Wa z0oneassod6d that foundatiam extend through any loose surficial or fill soils for bearing support. Thersforo the potential influence of liquefaction on structures don to these soil types is low. The same reasoning may be applied to the attenuation of grand motion. Groefon Hazard Although this typo of hazard is not specifically referred to in the now ordinance, we commonly conduct our evaluations to include erosion hazards. The erosion hazard criteria used for determination of affected areas include soil type, slope gradient, vegetation cover and gromd crater conditions. The erosion sensitivity is related to vegetative cover and the specific surface soils typos (group classification), which are related to the underlying geologic soil/lock units. The following table is outlines erosion hazard for the en site soils that have been stripped of vegetation. The surface soils found within the site have bout classified in accordance with the Soil Conservation Service (Sc5) classification system and have been grouped with respect to the corresponding geologic unit. Geologic Unit Surface Soil Sensitivity At slope 0-15% 16-391 v10% QuT Alderwood Low fled High (Glacial Till) Qi Kitaap Low Hod High (Fh idboy Floc) Landslide Hazard (Unstable Soils Hazards Areas) An evaluation of landslide hazard was performed for this site. This evaluation includes soil typo, underlying stratigraphy, slope gradient, ground water conditions and vegetation cover. Using these criteria, it is our opinion that the site slopes are relatively stable with no apparent signs of sliding or slurping ground conditions. Since the steeper portions of the slope areas were found to be underlain primarily by dense glacial till and stiff to hard Whidbey Fooaation deposits, 885